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1.
Nat Commun ; 15(1): 5576, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38956078

RESUMO

Strongly correlated materials respond sensitively to external perturbations such as strain, pressure, and doping. In the recently discovered superconducting infinite-layer nickelates, the superconducting transition temperature can be enhanced via only ~ 1% compressive strain-tuning with the root of such enhancement still being elusive. Using resonant inelastic x-ray scattering (RIXS), we investigate the magnetic excitations in infinite-layer PrNiO2 thin films grown on two different substrates, namely SrTiO3 (STO) and (LaAlO3)0.3(Sr2TaAlO6)0.7 (LSAT) enforcing different strain on the nickelates films. The magnon bandwidth of PrNiO2 shows only marginal response to strain-tuning, in sharp contrast to the enhancement of the superconducting transition temperature Tc in the doped superconducting samples. These results suggest the bandwidth of spin excitations of the parent compounds is similar under strain while Tc in the doped ones is not, and thus provide important empirics for the understanding of superconductivity in infinite-layer nickelates.

2.
Ann Geriatr Med Res ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38952332

RESUMO

Background: This study aimed to develop an instrument for assessing physical functioning among adults aged 50 years or older living in the community. Methods: Based on a review of various national health surveys and cohort studies, a 144-item bank was constructed for assessing physical functioning. Focus group interviews were conducted among adults aged 50 years or older to investigate their level of understanding of 60 selected items, followed by a pretest of the items on a nationally representative sample (n = 508). The final 25-item questionnaire was tested on an independent sample (n = 259) for validity and reliability based on classical test and item response theories. Predictive validity at the 6-month follow-up was tested in a separate sample (n = 263). Results: The newly developed Life Functioning (LF) scale assessed the dimensions of functional limitations, disabilities, and social activities. The scale satisfied a one-dimensionality assumption with good item fit and demonstrated criterion validity, construct validity, high internal consistency (Cronbach's alpha = 0.93), and test-retest reliability (intra-class correlation coefficient = 0.84; 95% CI, 0.76-0.89). The LF scale comprised 25 items with a total score ranging from 0 to 100. Higher scores indicated higher levels of functioning. The LF score was significantly associated with the physical functioning score at 6 months. Conclusion: The LF scale was developed to assess the physical functioning of people in their late midlife or older. Future studies should test the instrument on a national sample and evaluate its application in diverse population subgroups.

3.
Diabetes Care ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940851

RESUMO

OBJECTIVE: Women with a history of gestational diabetes mellitus (GDM) are at increased risk of developing type 2 diabetes (T2D). It remains unclear whether genetic information improves prediction of incident T2D in these women. RESEARCH DESIGN AND METHODS: Using five independent cohorts representing four different ancestries (n = 1,895), we investigated whether a genome-wide T2D polygenic risk score (PRS) is associated with increased risk of incident T2D. We also calculated the area under the receiver operating characteristics curve (AUROC) and continuous net reclassification improvement (NRI) following the incorporation of T2D PRS into clinical risk models to assess the diagnostic utility. RESULTS: Among 1,895 women with previous history of GDM, 363 (19.2%) developed T2D in a range of 2 to 30 years. T2D PRS was higher in those who developed T2D (-0.08 vs. 0.31, P = 2.3 × 10-11) and was associated with an increased risk of incident T2D (odds ratio 1.52 per 1-SD increase, 95% CI 1.05-2.21, P = 0.03). In a model that includes age, family history of diabetes, systolic blood pressure, and BMI, the incorporation of PRS led to an increase in AUROC for T2D from 0.71 to 0.74 and an intermediate improvement of NRI (0.32, 95% CI 0.15-0.49, P = 3.0 × 10-4). Although there was variation, a similar trend was observed across study cohorts. CONCLUSIONS: In cohorts of GDM women with diverse ancestry, T2D PRS was significantly associated with future development of T2D. A significant but small improvement was observed in AUROC when T2D PRS was integrated into clinical risk models to predict incident T2D.

4.
J Clin Med ; 13(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38892918

RESUMO

Background: This study examines the relationship between physical and mental function and frailty, independently and in conjunction with polypharmacy, among older adults. Methods: This cross-sectional study consisted of 368 participants aged ≥60 years. The participants were categorized into either robust or frail groups using Fried's frailty phenotype. Physical functions were assessed using grip strength, gait speed, Timed Up and Go (TUG), the Five Chair Sit to Stand Test (FCSST) and the Six-Minute Walk Test (SMWT). Mental functions were assessed using cognitive function and depression. Cognitive function was measured using Mini-Mental State Examination (MMSE). Depression was assessed with the Korean version of the Short Geriatric Depression Scale (SGDS). Results: The mean age of study population was 75.4 years. In this population, we identified 78.8% (n = 290) robust participants and 21.2% (n = 78) frail participants. The study examined frailty status (frail vs. non-frail) and frailty with and without polypharmacy using multivariate logistic regressions, adjusting for age and sex. In the logistic regression model estimating the risk of frailty, after adjustments for age, sex, BMI, and number of medications, individuals with low SMWT showed a significantly increased risk of frailty, with an odds ratio (OR) of 8.66 and a 95% confidence interval (CI) of 4.55-16.48. Additionally, global cognitive function was associated with a 1.97-fold increase in frailty risk (95% CI: 1.02-3.67). Moreover, in models adjusted for age, sex, and BMI to assess frailty risk linked to polypharmacy, the TUG, SMWT, and SGDS all showed increased risks, with ORs of 3.65 (95% CI: 1.07-12.47), 5.06 (95% CI: 1.40-18.32), and 5.71 (95% CI: 1.79-18.18), respectively. Conclusions: Physical function (SMWT, FCSST, TUG) and mental function (depression, cognition) were associated with frailty. By comprehensively examining these factors, we will gain valuable insights into frailty and enable more precise strategies for intervention and prevention.

5.
BMB Rep ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38919015

RESUMO

Antigen 43 (Ag43) proteins, found on the outer membrane of Escherichia coli, are ß-sheets that fold into a unique cylindrical structure known as a ß-barrel. There are several known structural similarities between bacterial Ag43 autotransporters and physical components; however, the factors that stabilize the barrel and the mechanism for Ag43 passenger domainmediated translocation across the pore of the ß-barrel remain unclear. In this study, we analyzed Ag43ß-enhanced green fluorescent protein chimeric variants to provide new insights into the autotransporter Ag43 ß-barrel assembly, focusing on the impact of the α-helical linker domain. Among the chimeric variants, Ag43ß700 showed the highest surface display, which was confirmed through extracellular protease digestion, flow cytometry, and an evaluation of outer membrane vesicles (OMVs). The Ag43ß700 module offered reliable information on stable barrel folding and chimera expression at the exterior of the OMVs.

6.
Int J Mol Sci ; 25(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38891805

RESUMO

Plasmodium knowlesi is the only Plasmodium that causes zoonotic disease among the Plasmodium that cause infection in humans. It is fatal due to its short asexual growth cycle within 24 h. Lactate dehydrogenase (LDH), an enzyme that catalyzes the final step of glycolysis, is a biomarker for diagnosing infection by Plasmodium spp. parasite. Therefore, this study aimed to efficiently produce the soluble form of P. knowlesi LDH (PkLDH) using a bacterial expression system for studying malaria caused by P. knowlesi. Recombinant pET-21a(+)-PkLDH plasmid was constructed by inserting the PkLDH gene into a pET-21a(+) expression vector. Subsequently, the recombinant plasmid was inserted into the protein-expressing Escherichia coli Rosetta(DE3) strain, and the optimal conditions for overexpression of the PkLDH protein were established using this strain. We obtained a yield of 52.0 mg/L PkLDH from the Rosetta(DE3) strain and confirmed an activity of 483.9 U/mg through experiments. This methodology for high-efficiency PkLDH production can be utilized for the development of diagnostic methods and drug candidates for distinguishing malaria caused by P. knowlesi.


Assuntos
Clonagem Molecular , L-Lactato Desidrogenase , Malária , Plasmodium knowlesi , Plasmodium knowlesi/genética , Plasmodium knowlesi/enzimologia , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Clonagem Molecular/métodos , Malária/parasitologia , Malária/diagnóstico , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Animais , Humanos , Expressão Gênica , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
7.
Diabetes Care ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829722

RESUMO

OBJECTIVE: While most genetic variants of type 2 diabetes (T2D) are suggested to be associated with ß-cell dysfunction cross sectionally, their association with the longitudinal change of ß-cell function remains largely unknown. RESEARCH DESIGN AND METHODS: We analyzed data from 6,311 participants without T2D at baseline (mean [SD] age 51.6 [8.7] years) from a community-based prospective cohort in Korea. Participants underwent biennial 2-h 75-g oral glucose tolerance tests (OGTTs) during 14 years of follow-up, and the OGTT-derived disposition index (DI) was used as a marker for ß-cell function. Genetic risk was quantified using the genome-wide polygenic risk score (PRS) and was stratified into low (1st quintile), intermediate (2nd-4th quintiles), and high (5th quintile) genetic risk. Lifestyle was assessed according to Life's Essential 8. RESULTS: During a mean follow-up of 10.9 years, 374 (29.6%), 851 (22.5%), and 188 (14.9%) participants developed T2D in the high, intermediate, and low genetic risk groups, respectively. Compared with the low genetic risk group, participants in the high genetic risk group had a 25% lower DI at baseline. Furthermore, in longitudinal analysis, we observed a 1.83-fold faster decline in log2-transformed DI per year (-0.034 vs. -0.019, P = 2.1 × 10-3; per 1-SD increase in T2D PRS, P = 1.2 × 10-4). Healthy lifestyle attenuated the rate of decline in DI across all genetic risk groups. CONCLUSIONS: Individuals with a higher genetic risk for T2D exhibited not only a lower OGTT-derived ß-cell function at baseline but also a notably more rapid decline during follow-up. This information could be used to enable a focused precision prevention with lifestyle intervention.

8.
Heart Rhythm ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38697272

RESUMO

BACKGROUND: The association between alcohol consumption and the risk of sudden cardiac death and/or fatal ventricular arrhythmia remains controversial. OBJECTIVE: We analyzed the association between alcohol consumption, genetic traits for alcohol metabolism, and the risk of sudden cardiac death and/or fatal ventricular arrhythmia. METHODS: We identified 397,164 individuals enrolled between 2006 and 2010 from the UK Biobank database and followed them until 2021. Alcohol consumption was categorized as current nondrinkers (nondrinkers and ex-drinkers), mild drinkers, moderate drinkers, or heavy drinkers. Genetic traits of alcohol metabolism were stratified according to the polygenic risk score tertiles. The primary and secondary outcomes were a composite of sudden cardiac death and fatal ventricular arrhythmia as well as their individual components. RESULTS: During follow-up (median 12.5 years), 3543 cases (0.89%) of clinical outcomes occurred. Although mild, moderate, and heavy drinkers showed deceased risks of outcomes compared with current nondrinkers, there was no prognostic difference among nondrinkers, mild drinkers, moderate drinkers, and heavy drinkers. Ex-drinkers showed an increased risk in univariate analysis, but the significance was attenuated after adjusting covariates (hazard ratio 1.19; 95% confidence interval 0.94-1.50). As a continuous variable, alcohol consumption was not associated with clinical outcomes (hazard ratio 1.01; 95% confidence interval 0.99-1.02). Consistent with these findings, there was no association between genetic traits for alcohol metabolism and the risk of clinical outcomes. CONCLUSION: Alcohol consumption was neither a protective factor nor a risk factor for sudden cardiac death or fatal ventricular arrhythmia. Genetic traits of alcohol metabolism were not associated with the clinical prognosis.

9.
Microorganisms ; 12(5)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38792706

RESUMO

Malaria is one of the most prevalent diseases worldwide with high incidence and mortality. Among the five species that can infect humans, Plasmodium ovale morphologically resembles Plasmodium vivax, resulting in misidentification and confusion in diagnosis, and is responsible for malarial disease relapse due to the formation of hypnozoites. P. ovale receives relatively less attention compared to other major parasites, such as P. falciparum and P. vivax, primarily due to its lower pathogenicity, mortality rates, and prevalence rates. To efficiently produce lactate dehydrogenase (LDH), a major target for diagnosing malaria, this study used three Escherichia coli strains, BL21(DE3), BL21(DE3)pLysS, and Rosetta(DE3), commonly used for recombinant protein production. These strains were characterized to select the optimal strain for P. ovale LDH (PoLDH) production. Gene cloning for recombinant PoLDH production and transformation of the three strains for protein expression were performed. The optimal PoLDH overexpression and washing buffer conditions in nickel-based affinity chromatography were established to ensure high-purity PoLDH. The yields of PoLDH expressed by the three strains were as follows: BL21(DE3), 7.6 mg/L; BL21(DE3)pLysS, 7.4 mg/L; and Rosetta(DE3), 9.5 mg/L. These findings are expected to be highly useful for PoLDH-specific diagnosis and development of antimalarial therapeutics.

10.
Sci Rep ; 14(1): 11419, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38763924

RESUMO

A novel auxetic structure applicable to airless tire spokes is designed based on the primitive-type triply periodic minimal surface (P-TPMS) to have higher stiffness through deformation under compressive force. For becoming higher stiffness by deformation, an unit cell of auxetic structure is proposed and its characteristics according to design parameters are studied. Based on the parametric study, a rotated primitive-type auxetic structure (RPAS) is designed, and the deformative behaviors of an airless tire with the RPAS spokes are compared with a generally used honeycomb spoke. Simulation and experiment results show that the designed RPAS tire exhibits more stable behavior through higher rigidity depending on the deformation state when compressed on flat ground and obstacles. This variable stiffness characteristic of RPAS tires can be advantageous for shock absorption and prevention of large local deformations. Also, the manufacturability of the designed auxetic structure is evaluated using real rubber-based additive manufacturing processes for practical application in the tire manufacturing industry.

11.
Neuropsychiatr Dis Treat ; 20: 1097-1106, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774254

RESUMO

Objective: The purpose of this study was to evaluate the positive impact of mobile neurofeedback (MNF) in neurotypical children compared to sham mobile neurofeedback. Methods: Neurotypical children aged 10-15 participated in the study. All subjects were assessed using the Kiddie Schedule for Affective Disorders and Schizophrenia Present and Lifetime Version Korean Version (K-SADS-PL-K) and confirmed to have no psychiatric symptoms. The participants were randomly assigned to the MNF active (N=31) or sham control (N=30) groups. The MNF program was administered using a mobile app for 30 min/day, 3 days/week, for 3 months. All participants and their parents completed self-report scales and participants complete neurocognitive function assessments including the continuous performance test, Stroop, children's color trails test-1 and 2, and intelligence test at baseline and after the 3-month MNF program. Results: This study involved 61 participants (mean [SD] age, 11.24 [1.84] years; 30 male participants [49.2%]). To verify the difference between the MNF group and the sham group, 2(MNF-Sham) X 2(Pre-Post) repeated measures ANOVA was performed. The main effect of the K-scale (Korea Internet addiction scale) between-group factor (MNF vs Sham) was not significant, but the main effect of the within-group factor (Pre vs Post) was significant (F=7.595, p=0.008). The interaction effect of between-group factors and within-group factors was also significant (F=5.979, p=0.017). In other self-reported scales of children and parents and neurocognitive function assessments, there was no significant difference between the two groups. Conclusion: Active mobile neurofeedback significantly improved children's K-scale score compared to the sham group. Therefore, mobile neurofeedback could be an easy-to-access therapeutic option for children at risk of Internet addiction. On the other hand, there was no significant difference in other scales and neurocognitive function. A 3-month intervention may not have been long enough to cause change, so longer interventions are needed for confirmation.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38615329

RESUMO

Cell membranes are structures essential to the cell function and adaptation. Recent studies have targeted cell membranes to identify their protective and interactive properties. Leveraging these attributes of cellular membranes and their application to vaccine delivery is gaining increasing prominence. This study aimed to fuse synthetic polymeric nanoparticles with cell membranes to develop cell membrane hybrid polymersomes (HyPSomes) for enhanced vaccine delivery. We designed a platform to hybridize cell membranes with methoxy-poly(ethylene glycol)-block-polylactic acid nanoparticles by using the properties of both components. The formed HyPSomes were optimized by using dynamic light scattering, transmission electron microscopy, and Förster resonance energy transfer, and their stability was confirmed. The synthesized HyPSomes replicated the antigenic surface of the source cells and possessed the stability and efficacy of synthetic nanoparticles. These HyPSomes demonstrated enhanced cellular uptake and translation efficiency and facilitated endosome escape. HyPSomes showed outstanding capabilities for the delivery of foreign mRNAs to antigen-presenting cells. HyPSomes may serve as vaccine delivery systems by bridging the gap between synthetic and natural systems. These systems could be used in other contexts, e.g., diagnostics and drug delivery.

13.
Nat Commun ; 15(1): 3368, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643233

RESUMO

The immune escape of Omicron variants significantly subsides by the third dose of an mRNA vaccine. However, it is unclear how Omicron variant-neutralizing antibodies develop under repeated vaccination. We analyze blood samples from 41 BNT162b2 vaccinees following the course of three injections and analyze their B-cell receptor (BCR) repertoires at six time points in total. The concomitant reactivity to both ancestral and Omicron receptor-binding domain (RBD) is achieved by a limited number of BCR clonotypes depending on the accumulation of somatic hypermutation (SHM) after the third dose. Our findings suggest that SHM accumulation in the BCR space to broaden its specificity for unseen antigens is a counterprotective mechanism against virus variant immune escape.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Vacina BNT162 , COVID-19/prevenção & controle , SARS-CoV-2/genética , Anticorpos Neutralizantes , Anticorpos Antivirais
14.
RSC Adv ; 14(14): 9943-9966, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38528920

RESUMO

This review examines the escalating issue of plastic pollution, specifically highlighting the detrimental effects on the environment and human health caused by microplastics and nanoplastics. The extensive use of synthetic polymers such as polyethylene (PE), polyethylene terephthalate (PET), and polystyrene (PS) has raised significant environmental concerns because of their long-lasting and non-degradable characteristics. This review delves into the role of enzymatic and microbial strategies in breaking down these polymers, showcasing recent advancements in the field. The intricacies of enzymatic degradation are thoroughly examined, including the effectiveness of enzymes such as PETase and MHETase, as well as the contribution of microbial pathways in breaking down resilient polymers into more benign substances. The paper also discusses the impact of chemical composition on plastic degradation kinetics and emphasizes the need for an approach to managing the environmental impact of synthetic polymers. The review highlights the significance of comprehending the physical characteristics and long-term impacts of micro- and nanoplastics in different ecosystems. Furthermore, it points out the environmental and health consequences of these contaminants, such as their ability to cause cancer and interfere with the endocrine system. The paper emphasizes the need for advanced analytical methods and effective strategies for enzymatic degradation, as well as continued research and development in this area. This review highlights the crucial role of enzymatic and microbial strategies in addressing plastic pollution and proposes methods to create effective and environmentally friendly solutions.

15.
Adv Healthc Mater ; 13(17): e2303782, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38430208

RESUMO

Exosomes are small extracellular vesicles that play a crucial role in intercellular communication and offer significant potential for a wide range of biomedical applications. However, conventional methods for exosome isolation have limitations in terms of purity, scalability, and preservation of exosome structural integrity. To address these challenges, an exosome isolation platform using chitosan oligosaccharide lactate conjugated 1-pyrenecarboxylic acid (COL-Py) based self-assembled magnetic nanoclusters (CMNCs), is presented. CMNCs are characterized to optimize their size, stability, and interaction dynamics with exosomes. The efficiency of CMNCs in isolating exosomes is systematically evaluated using various analytical methods to demonstrate their ability to capture exosomes based on amphiphilic lipid bilayers. CMNC-based exosome isolation consistently yields exosomes with structural integrity and purity similar to those obtained using traditional methods. The reusability of CMNCs over multiple exosome isolation cycles underscores their scalability and offers an efficient solution for biomedical applications. These results are supported by western blot analysis, which demonstrated the superiority of CMNC-based isolation in terms of purity compared to conventional methods. By providing a scalable and efficient exosome isolation process that preserves both structural integrity and purity, CMNCs can constitute a new platform that can contribute to the field of exosome studies.


Assuntos
Quitosana , Exossomos , Quitosana/química , Exossomos/química , Exossomos/metabolismo , Humanos , Oligossacarídeos/química , Pirenos/química , Nanopartículas de Magnetita/química , Ácido Láctico/química , Ácidos Carboxílicos/química
16.
Toxicol In Vitro ; 97: 105810, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513818

RESUMO

Grown evidence has shown that the liver and reproductive organs were the main target organs of perfluorooctanoic acid (PFOA). Herein, we studied a toxic mechanism of PFOA using HeLa Chang liver epithelial cells. When incubated with PFOA for 24 h or 48 h, cell proliferation was inhibited in a concentration- and time-dependent fashion, but interestingly, the feature of dead cells was not notable. Mitochondrial volume was increased with concentration and time, whereas the mitochondrial membrane potential and produced ATP amounts were significantly reduced. Autophagosome-like vacuoles and contraction of the mitochondrial inner membrane were observed in PFOA-treated cells. The expression of acetyl CoA carboxylase (ACC) and p-ACC proteins rapidly decreased, and that of mitochondrial dynamics-related proteins increased. The expression of solute carrier family 7 genes, ChaC glutathione-specific gamma-glutamylcyclotransferase 1, and 5S ribosomal RNA gene was up-regulated the most in cells exposed to PFOA for 24 h, and the KEGG pathway analysis revealed that PFOA the most affected metabolic pathways and olfactory transduction. More importantly, PPAR alpha, fatty acid binding protein 1, and CYP450 family 1 subfamily A member 1 were identified as the target proteins for binding between PFOA and cells. Taken together, we suggest that disruption of mitochondrial integrity and function may contribute closely to PFOA-induced cell proliferation inhibition.


Assuntos
Caprilatos , Fluorocarbonos , Caprilatos/metabolismo , Fígado/metabolismo , Hepatócitos , Fluorocarbonos/metabolismo , Proliferação de Células
17.
Redox Biol ; 71: 103101, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38408409

RESUMO

Physical activity has been considered an important non-medication intervention in preserving mnemonic processes during aging. However, how aerobic exercise promotes such benefits for human health remains unclear. In this study, we aimed to explore the neuroprotective and anti-inflammatory effects of aerobic exercise against lipopolysaccharide (LPS)-induced amnesic C57BL/6J mice and BV-2 microglial cell models. In the in vivo experiment, the aerobic exercise training groups were allowed to run on a motorized treadmill 5 days/week for 4 weeks at a speed of 10 rpm/min, with LPS (0.1 mg/kg) intraperitoneally injected once a week for 4 weeks. We found that aerobic exercise ameliorated memory impairment and cognitive deficits among the amnesic mice. Correspondingly, aerobic exercise significantly increased the protein expressions of FNDC5, which activates target neuroprotective markers BDNF and CREB, and antioxidant markers Nrf2/HO-1, leading to inhibiting microglial-mediated neuroinflammation and reduced the expression of BACE-1 in the hippocampus and cerebral cortex of amnesic mice. We estimated that aerobic exercise inhibited neuroinflammation in part through the action of FNDC5/irisin on microglial cells. Therefore, we explored the anti-inflammatory effects of irisin on LPS-stimulated BV-2 microglial cells. In the in vitro experiment, irisin treatment blocked NF-κB/MAPK/IRF3 signaling activation concomitantly with the significantly lowered levels of the LPS-induced iNOS and COX-2 elevations and promotes the Nrf2/HO-1 expression in the LPS-stimulated BV-2 microglial cells. Together, our findings suggest that aerobic exercise can improve the spatial learning ability and cognitive functions of LPS-treated mice by inhibiting microglia-mediated neuroinflammation through its effect on the expression of BDNF/FNDC5/irisin.


Assuntos
Disfunção Cognitiva , Lipopolissacarídeos , Camundongos , Humanos , Animais , Lipopolissacarídeos/efeitos adversos , Doenças Neuroinflamatórias , Fibronectinas/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Camundongos Endogâmicos C57BL , Disfunção Cognitiva/terapia , Disfunção Cognitiva/tratamento farmacológico , Estresse Oxidativo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , NF-kappa B/metabolismo , Inflamação/terapia , Inflamação/tratamento farmacológico
18.
Heliyon ; 10(4): e26663, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38420468

RESUMO

Myasthenia Gravis (MG) patients with anti-acetylcholine receptor (AChR) antibodies frequently show hyperplastic thymi with ectopic germinal centers, where autoreactive B cells proliferate with the aid of T cells. In this study, thymus and peripheral blood (PB) samples were collected from ten AChR antibody-positive MG patients. T cell receptor (TCR) repertoires were analyzed using next-generation sequencing (NGS), and compared with that of an age and sex matched control group generated from a public database. Certain V genes and VJ gene recombination pairs were significantly upregulated in the TCR chains of αß-T cells in the PB of MG patients compared to the control group. Furthermore, the TCR chains found in the thymi of MG patients had a weighted distribution to longer CDR3 lengths when compared to the PB of MG patients, and the TCR beta chains (TRB) in the MG group's PB showed increased clonality encoded by one upregulated V gene. When TRB sequences were sub-divided into groups based on their CDR3 lengths, certain groups showed decreased clonality in the MG group's PB compared to the control group's PB. Finally, we demonstrated that stereotypic MG patient-specific TCR clonotypes co-exist in both the PB and thymi at a much higher frequency than that of the clonotypes confined to the PB. These results strongly suggest the existence of a biased T cell-mediated immune response in MG patients, as observed in other autoimmune diseases.

19.
Discov Nano ; 19(1): 23, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315307

RESUMO

There is growing evidence that neonatal porcine islet-like cell clusters (NPCCs) isolated from piglets can be used to treat type 1 diabetes in humans. However, graft rejection is a common complication in humans owing to the prevalence of xenoantigens in porcine. Therefore, researchers have investigated various islet encapsulation techniques that could protect against these antigens. To this end, this study presents a robust nano-encapsulation method based on bifunctional polymersomes (PSomes), in which N-hydroxysuccinimide (NHS) and maleimide (Mal) groups conjugated to the PSomes terminal interact with the amine and thiol groups on the surface of NPCCs to induce dual targeting via two covalent bonds. The findings indicate that the ratio of NHS to Mal on PSomes is optimal for dual targeting. Moreover, triiodothyronine (T3) is known to promotes pancreatic islet maturation and differentiation of endocrine cells into beta cells. T3 encapsulated in PSomes is shown to increase the glucose sensitivity of NPCCs and enhance insulin secretion from NPCCs. Furthermore, improvements in the nano-encapsulation efficiency and insulin-secreting capability of NPCCs through dual targeting via dual-Psomes are demonstrated. In conclusion, the proposed nano-encapsulation technique could pave the way for significant advances in islet nano-encapsulation and the imprevement of NPCC immaturity via T3 release.

20.
Nat Mach Intell ; 6(2): 180-186, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38404481

RESUMO

The removal or cancellation of noise has wide-spread applications in imaging and acoustics. In applications in everyday life, such as image restoration, denoising may even include generative aspects, which are unfaithful to the ground truth. For scientific use, however, denoising must reproduce the ground truth accurately. Denoising scientific data is further challenged by unknown noise profiles. In fact, such data will often include noise from multiple distinct sources, which substantially reduces the applicability of simulation-based approaches. Here we show how scientific data can be denoised by using a deep convolutional neural network such that weak signals appear with quantitative accuracy. In particular, we study X-ray diffraction and resonant X-ray scattering data recorded on crystalline materials. We demonstrate that weak signals stemming from charge ordering, insignificant in the noisy data, become visible and accurate in the denoised data. This success is enabled by supervised training of a deep neural network with pairs of measured low- and high-noise data. We additionally show that using artificial noise does not yield such quantitatively accurate results. Our approach thus illustrates a practical strategy for noise filtering that can be applied to challenging acquisition problems.

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