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1.
J Chin Med Assoc ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651853

RESUMO

BACKGROUND: Mori Radicis Cortex (MRC) is the root bark of the mulberry family as Morus alba L. In Korea, it is known as "Sangbaegpi". While MRC has demonstrated anti-inflammatory and antioxidant effects, its specific mechanisms of action and impact on osteoporosis remain poorly understood. METHODS: To investigate the anti-osteoporosis effect of MRC, we examined the level of osteoclast differentiation inhibition in receptor activator of nuclear factor kappa-Β ligand (RANKL)-induced-RAW 264.7 cells and animal models of ovariectomy (OVX) with MRC. Serum analysis in OVX animals was investigated by enzyme-linked immunosorbent assay (ELISA), and bone density analysis was confirmed by micro-computed tomography (micro-CT). The expression analysis of NFATc1 was confirmed by immunohistochemistry (IHC) in femur tissue. In addition, osteoclast differentiation inhibition was measured using tartrate-resistant acid phosphatase (TRAP). mRNA analysis was performed using reverse transcription polymerase chain reaction (RT-PCR), and the protein expression analysis was investigated by western blot. RESULTS: Micro-CT analysis showed that MRC effectively inhibited bone loss in the OVX-induced rat model. MRC also inhibited the expression of alkaline phosphatase (ALP) and TRAP in serum. Histological analysis showed that MRC treatment increased bone density and IHC analysis showed that MRC significantly inhibited the expression of NFATc1. In RANKL-induced-RAW 264.7 cells, MRC significantly reduced TRAP activity and actin ring formation. In addition, MRC significantly inhibited the expression of nuclear factor of activated T cells 1 (NFATc1)/ and c-Fos, and suppressed the mRNA expression. CONCLUSION: Based on micro-CT, serum and histological analysis, MRC effectively inhibited bone loss in an OVX-induced rat model. In addition, MRC treatment suppressed the expression of osteoclast differentiation, fusion, and bone resorption markers through inhibition of NFATc1/c-Fos expression in RANKL-induced RAW 264.7 cells, ultimately resulting in a decrease in osteoclast activity. These results demonstrate that MRC is effective in preventing bone loss through inhibiting osteoclast differentiation and activity.

2.
J Am Soc Nephrol ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593157

RESUMO

BACKGROUND: Trimethylamine N-oxide (TMAO) is a gut microbiota-derived metabolite of dietary phosphatidylcholine and carnitine. Experimentally, TMAO causes kidney injury and tubulointerstitial fibrosis. Little is known about prospective associations between TMAO and kidney outcomes, especially incident CKD. We hypothesized that higher plasma TMAO levels would be associated with higher risk of incident CKD and greater rate of kidney function decline. METHODS: We included 10,564 participants from two community-based, prospective cohorts with estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73m2 to assess incident CKD. TMAO was measured using targeted mass spectrometry at baseline and one follow-up visit. Creatinine and Cystatin C were measured up to 4 times during follow-up and used to compute eGFR. Incident CKD was defined as an eGFR decline ≥ 30% from baseline and a resulting eGFR<60 ml/min/1.73 m2. Time-varying Cox models assessed the association of serial TMAO measures with incident CKD, adjusting for sociodemographic, lifestyle, diet, and cardiovascular disease risk factors. Linear mixed models assessed the association with annualized eGFR change in 10,009 participants with at least one follow-up eGFR measure without exclusions for baseline eGFR levels. RESULTS: During a median follow-up of 9.4 years (interquartile range: 9.1-11.6 years), 979 incident CKD events occurred. Higher TMAO levels associated with higher risk of incident CKD (2nd to 5th vs. 1st quintile HR[95%CI]= 1.65 [1.22-2.23], 1.68 [1.26-2.25], 2.28 [1.72-3.02], and 2.24[1.68-2.98], respectively) and greater annualized eGFR decline ( 2nd to 5th vs. 1st quintile annualized eGFR change= -0.21 [-0.32, -0.09], -0.17 [-0.29, -0.05], -0.35 [-0.47, -0.22], and -0.43[-0.56, -0.30], respectively) with monotonic dose-response relationships. These associations were consistent across different racial/ethnic groups examined. The association with eGFR decline was similar to or larger than that seen for established CKD risk factors including diabetes, per 10 mmHg of higher systolic blood pressure, per 10 years of older age, and Black race. CONCLUSIONS: In community-based US adults, higher serial measures of plasma TMAO were associated with higher risk of incident CKD and greater annualized kidney function decline.

3.
Nutrition ; 122: 112374, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38430845

RESUMO

OBJECTIVE: This study aimed to investigate the association between ultra-processed food (UPF) intake and the risk for metabolic syndrome (MetS) in Korean adults. METHODS: The study consisted of 22 688 Korean adults ≥19 y of age from the Korea National Health and Nutrition Examination Survey (KNHANES) 2016-2020. The NOVA classification categorizes foods according to the nature, extent, and purpose of industrial processing. MetS was defined based on the National Cholesterol Education Program Adult Treatment Panel III criteria and a modified waist circumference cut-off for Korean adults. We estimated the usual percent total food intake from UPFs. We used multivariate logistic regression to assess the association between UPFs and risk for MetS, adjusted for age, sex, education level, income level, smoking status, alcohol drinking, physical activity, and total energy intake. We further analyzed the association of UPFs with each component of MetS. RESULTS: The median usual percent total food intake from UPFs was 22%, and the midpoint of intake ranged from 3% (quartile 1) to 48% (quartile 4). The group with the highest UPF consumption had a 19% higher risk for developing MetS than the lowest quartile of UPF consumption (odds ratio [OR],1.19; 95% confidence interval [CI], 1.06-1.33; Ptrend = 0.006). In analysis of the relationship between UPF intake and MetS components, a higher UPF was associated with an increased risk for hypertension (OR, 1.13; 95% CI, 1.01-1.26; Ptrend = 0.037) and abdominal obesity (OR, 1.19; 95% CI, 1.07-1.33; Ptrend = 0.001), but had no significant association with other components (hyperglycemia, hypertriacylglycerolmia, and low high-density lipoprotein cholesterol, all P > 0.05). CONCLUSION: Higher UPF contribution to total daily food intake is associated with an increased risk for MetS, particularly with a higher risk for hypertension and abdominal obesity.


Assuntos
Hipertensão , Síndrome Metabólica , Adulto , Humanos , Síndrome Metabólica/etiologia , Síndrome Metabólica/complicações , Estudos Transversais , Inquéritos Nutricionais , Alimento Processado , Obesidade Abdominal/etiologia , Obesidade Abdominal/complicações , Obesidade/epidemiologia , Obesidade/etiologia , Colesterol , República da Coreia/epidemiologia , Dieta/efeitos adversos , Manipulação de Alimentos , Fast Foods/efeitos adversos
4.
Psychiatry Res ; 335: 115882, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554495

RESUMO

We investigate the predictive factors of the mood recurrence in patients with early-onset major mood disorders from a prospective observational cohort study from July 2015 to December 2019. A total of 495 patients were classified into three groups according to recurrence during the cohort observation period: recurrence group with (hypo)manic or mixed features (MMR), recurrence group with only depressive features (ODR), and no recurrence group (NR). As a result, the baseline diagnosis of bipolar disorder type 1 (BDI) and bipolar disorder type 2 (BDII), along with a familial history of BD, are strong predictors of the MMR. The discrepancies in wake-up times between weekdays and weekends, along with disrupted circadian rhythms, are identified as a notable predictor of ODR. Our findings confirm that we need to be aware of different predictors for each form of mood recurrences in patients with early-onset mood disorders. In clinical practice, we expect that information obtained from the initial assessment of patients with mood disorders, such as mood disorder type, family history of BD, regularity of wake-up time, and disruption of circadian rhythms, can help predict the risk of recurrence for each patient, allowing for early detection and timely intervention.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Humanos , Transtornos do Humor/diagnóstico , Estudos Prospectivos , Transtorno Depressivo Maior/diagnóstico , Transtorno Bipolar/diagnóstico , Ritmo Circadiano , Recidiva
5.
Biomed Opt Express ; 15(3): 1540-1552, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38495693

RESUMO

We propose a new speckle-based plethysmography technique, termed rolling shutter speckle plethysmography (RSSPG), which can quantitatively measure the velocity and volume fluctuations of blood flow during the cardiac cycle. Our technique is based on the rolling shutter speckle imaging, where the short row-by-row time differences in the rolling shutter image sensors are used to measure the temporal decorrelation behavior of vertically elongated speckles from a single image capture. Temporal analysis of the speckle field provides rich information regarding the dynamics of the scattering media, such as both the dynamic scattering fraction and the speckle decorrelation time. Using a sequence of images, RSSPG can monitor fluctuations in the blood flow dynamics while separating velocity and volume changes in blood vessels and obtaining high-quality plethysmography waveforms compared to regular photoplethysmography. We demonstrate the quantitative RSSPG based on accurate fitting of the speckle dynamics model, as well as the qualitative RSSPG based on simple row-by-row correlation (RIC) calculation for fast and robust analysis. Based on exploratory in vivo experiment, we show that RSSPG can reliably measure pulsatile waveforms and heart rate variations in various conditions, potentially providing physiologically relevant information for cardiovascular monitoring.

6.
Biochem Biophys Rep ; 38: 101684, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38511188

RESUMO

Background: Regular physical activities reduce the growth of breast cancer, but research on the effects of steady exercise on metastasis and its mechanisms is limited. In this study, the effects of steady exercise on breast cancer metastasis and its possible mechanism were demonstrated. Methods: Experimental metastasis was induced after 8 weeks of steady exercise using a mouse model. Furthermore, one of the myokines, irisin, was studied to elucidate the effects of metastasis-regulating protein expression, and colony and sphere formation, which are cancer stem cell properties. Results: Low- and moderate-intensity exercise significantly reduced the number and volume of metastasized tumors. Among myokines, only irisin was significantly increased by steady exercise but decreased by a high-fat diet. In vitro studies, irisin significantly decreased the number of colonies and sphere formation. Irisin also inhibited cell migration and invasion and suppressed the malignancy of breast cancer cells by reducing the expression of vimentin, MMP-2, MMP-9, and HIF-1 and by increasing the expression of TIMP-1 and TIMP-2. Conclusion: Steady exercise modulates myokine secretions and among them, irisin suppresses breast cancer metastasis by decreasing self-renewal properties and invasion regulating protein expressions. Thus, regular exercise may be beneficial in the prevention of breast tumor metastasis.

7.
J Neurosci ; 44(15)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38418220

RESUMO

The conformational state of DNA fine-tunes the transcriptional rate and abundance of RNA. Here, we report that G-quadruplex DNA (G4-DNA) accumulates in neurons, in an experience-dependent manner, and that this is required for the transient silencing and activation of genes that are critically involved in learning and memory in male C57/BL6 mice. In addition, site-specific resolution of G4-DNA by dCas9-mediated deposition of the helicase DHX36 impairs fear extinction memory. Dynamic DNA structure states therefore represent a key molecular mechanism underlying memory consolidation.One-Sentence Summary: G4-DNA is a molecular switch that enables the temporal regulation of the gene expression underlying the formation of fear extinction memory.


Assuntos
Quadruplex G , Masculino , Animais , Camundongos , Extinção Psicológica , RNA Helicases DEAD-box/química , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Medo , DNA/metabolismo
8.
Nature ; 626(7999): 626-634, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326614

RESUMO

Adoptive T cell therapies have produced exceptional responses in a subset of patients with cancer. However, therapeutic efficacy can be hindered by poor T cell persistence and function1. In human T cell cancers, evolution of the disease positively selects for mutations that improve fitness of T cells in challenging situations analogous to those faced by therapeutic T cells. Therefore, we reasoned that these mutations could be co-opted to improve T cell therapies. Here we systematically screened the effects of 71 mutations from T cell neoplasms on T cell signalling, cytokine production and in vivo persistence in tumours. We identify a gene fusion, CARD11-PIK3R3, found in a CD4+ cutaneous T cell lymphoma2, that augments CARD11-BCL10-MALT1 complex signalling and anti-tumour efficacy of therapeutic T cells in several immunotherapy-refractory models in an antigen-dependent manner. Underscoring its potential to be deployed safely, CARD11-PIK3R3-expressing cells were followed up to 418 days after T cell transfer in vivo without evidence of malignant transformation. Collectively, our results indicate that exploiting naturally occurring mutations represents a promising approach to explore the extremes of T cell biology and discover how solutions derived from evolution of malignant T cells can improve a broad range of T cell therapies.


Assuntos
Evolução Molecular , Imunoterapia Adotiva , Linfoma Cutâneo de Células T , Mutação , Linfócitos T , Humanos , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Citocinas/biossíntese , Citocinas/imunologia , Citocinas/metabolismo , Guanilato Ciclase/genética , Guanilato Ciclase/metabolismo , Imunoterapia Adotiva/métodos , Linfoma Cutâneo de Células T/genética , Linfoma Cutâneo de Células T/imunologia , Linfoma Cutâneo de Células T/patologia , Linfoma Cutâneo de Células T/terapia , Fosfatidilinositol 3-Quinases , Transdução de Sinais/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/transplante
9.
ACS Appl Mater Interfaces ; 16(9): 12095-12105, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38384197

RESUMO

Two-dimensional transition metal dichalcogenides (2D TMDCs) are considered promising alternatives to Si as channel materials because of the possibility of retaining their superior electronic transport properties even at atomic body thicknesses. However, the realization of high-performance 2D TMDC field-effect transistors remains a challenge owing to Fermi-level pinning (FLP) caused by gap states and the inherent high Schottky barrier height (SBH) within the metal contact and channel layer. This study demonstrates that high-quality van der Waals (vdW) heterojunction-based contacts can be formed by depositing semimetallic TiS2 onto monolayer (ML) MoS2. After confirming the successful formation of a TiS2/ML MoS2 heterojunction, the contact properties of vdW semimetal TiS2 were thoroughly investigated. With clean interfaces of the TiS2/ML MoS2 heterojunctions, atomic-layer-deposited TiS2 can induce gap-state saturation and suppress FLP. Consequently, compared with conventional evaporated metal electrodes, the TiS2/ML MoS2 heterojunctions exhibit a lower SBH of 8.54 meV and better contact properties. This, in turn, substantially improves the overall performance of the device, including its on-current, subthreshold swing, and threshold voltage. Furthermore, we believe that our proposed strategy for vdW-based contact formation will contribute to the development of 2D materials used in next-generation electronics.

11.
Biomed Opt Express ; 15(2): 1253-1267, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38404314

RESUMO

Rolling shutter speckle imaging (RSSI) is a single-shot imaging technique that directly measures the temporal dynamics of the scattering media using a low-cost rolling shutter image sensor and vertically elongated speckles. In this paper, we derive and validate a complete spatiotemporal intensity correlation (STIC) model for RSSI, which describes the row-by-row correlation of the dynamic speckles measured with a rolling shutter in the presence of static scattering. Our new model accounts for the finite exposure time of the detector, which can be longer than the sampling interval in RSSI. We derive a comprehensive model that works for all correlation times of rolling shutter measurements. As a result, we can correctly utilize all data points in RSSI, which improves the measurement accuracy and ranges of speckle decorrelation time and dynamic scattering fraction, as demonstrated by phantom experiments. With simulations and experiments, we provide an understanding of the design parameters of RSSI and the measurement range of the speckle dynamics.

12.
BMC Womens Health ; 24(1): 134, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378535

RESUMO

BACKGROUND: This study aimed to develop and evaluate the validity and reliability of a self-management self-efficacy for premature birth prevention (SMSE-PBP) in women of childbearing age (WCA). METHODS: Instrument development and validation were undertaken in three phases: conceptualization, item generation and evaluation of content validity, and evaluation of construct and concurrent validity and reliability. Data were analyzed using exploratory and second-order confirmatory factor analyses, and concurrent validity was examined using Pearson's correlation coefficients. The reliability was analyzed using omega hierarchical and Cronbach's ⍺. RESULTS: Content validity was assessed by experts and cognitive interviews of WCA. The SMSE-PBP consists of a second-order 3-dimension and 10-factor scale with 60 items; therefore, the construct and concurrent validity of the SMSE-PBP were supported. The omega values were 0.93 for pre-pregnancy SMSE-PBP, 0.92 for pregnancy SMSE-PBP, and 0.94 for hospital SMSE-PBP. Cronbach's ⍺ was 0.88 for pre-pregnancy SMSE-PBP, 0.96 for pregnancy SMSE-PBP, and 0.96 for hospital SMSE-PBP. CONCLUSIONS: The SMSE-PBP scale is valid and reliable for WCA; it is helpful for WCA and health professionals to assess women's SMSE-PBP and pre-pregnancy, pregnancy, or hospital SMSE-PBP. The next steps should include assessing the relationship with pregnancy health behaviors.


Assuntos
Nascimento Prematuro , Autogestão , Gravidez , Humanos , Feminino , Autoeficácia , Reprodutibilidade dos Testes , Nascimento Prematuro/prevenção & controle , Inquéritos e Questionários , Psicometria/métodos
13.
BMC Psychiatry ; 24(1): 128, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365637

RESUMO

BACKGROUND: The association between antihypertensive medication and schizophrenia has received increasing attention; however, evidence of the impact of antihypertensive medication on subsequent schizophrenia based on large-scale observational studies is limited. We aimed to compare the schizophrenia risk in large claims-based US and Korea cohort of patients with hypertension using angiotensin-converting enzyme (ACE) inhibitors versus those using angiotensin receptor blockers (ARBs) or thiazide diuretics. METHODS: Adults aged 18 years who were newly diagnosed with hypertension and received ACE inhibitors, ARBs, or thiazide diuretics as first-line antihypertensive medications were included. The study population was sub-grouped based on age (> 45 years). The comparison groups were matched using a large-scale propensity score (PS)-matching algorithm. The primary endpoint was incidence of schizophrenia. RESULTS: 5,907,522; 2,923,423; and 1,971,549 patients used ACE inhibitors, ARBs, and thiazide diuretics, respectively. After PS matching, the risk of schizophrenia was not significantly different among the groups (ACE inhibitor vs. ARB: summary hazard ratio [HR] 1.15 [95% confidence interval, CI, 0.99-1.33]; ACE inhibitor vs. thiazide diuretics: summary HR 0.91 [95% CI, 0.78-1.07]). In the older subgroup, there was no significant difference between ACE inhibitors and thiazide diuretics (summary HR, 0.91 [95% CI, 0.71-1.16]). The risk for schizophrenia was significantly higher in the ACE inhibitor group than in the ARB group (summary HR, 1.23 [95% CI, 1.05-1.43]). CONCLUSIONS: The risk of schizophrenia was not significantly different between the ACE inhibitor vs. ARB and ACE inhibitor vs. thiazide diuretic groups. Further investigations are needed to determine the risk of schizophrenia associated with antihypertensive drugs, especially in people aged > 45 years.


Assuntos
Hipertensão , Esquizofrenia , Adulto , Humanos , Anti-Hipertensivos/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores de Simportadores de Cloreto de Sódio/efeitos adversos , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico , Esquizofrenia/induzido quimicamente , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Hipertensão/diagnóstico , Estudos de Coortes
14.
mBio ; 15(2): e0327523, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38193728

RESUMO

The casein kinase 2 (CK2) complex has garnered extensive attention over the past decades as a potential therapeutic target for diverse human diseases, including cancer, diabetes, and obesity, due to its pivotal roles in eukaryotic growth, differentiation, and metabolic homeostasis. While CK2 is also considered a promising antifungal target, its role in fungal pathogens remains unexplored. In this study, we investigated the functions and regulatory mechanisms of the CK2 complex in Cryptococcus neoformans, a major cause of fungal meningitis. The cryptococcal CK2 complex consists of a single catalytic subunit, Cka1, and two regulatory subunits, Ckb1 and Ckb2. Our findings show that Cka1 plays a primary role as a protein kinase, while Ckb1 and Ckb2 have major and minor regulatory functions, respectively, in growth, cell cycle control, morphogenesis, stress response, antifungal drug resistance, and virulence factor production. Interestingly, triple mutants lacking all three subunits (cka1Δ ckb1Δ ckb2Δ) exhibited more severe phenotypic defects than the cka1Δ mutant alone, suggesting that Ckb1/2 may have Cka1-independent functions. In a murine model of systemic cryptococcosis, cka1Δ and cka1Δ ckb1Δ ckb2Δ mutants showed severely reduced virulence. Transcriptomic, proteomic, and phosphoproteomic analyses further revealed that the CK2 complex controls a wide array of effector proteins involved in transcriptional regulation, cell cycle control, nutrient metabolisms, and stress responses. Most notably, CK2 disruption led to dysregulation of key signaling cascades central to C. neoformans pathogenicity, including the Hog1, Mpk1 MAPKs, cAMP/PKA, and calcium/calcineurin signaling pathways. In summary, our study provides novel insights into the multifaceted roles of the fungal CK2 complex and presents a compelling case for targeting it in the development of new antifungal drugs.IMPORTANCEThe casein kinase 2 (CK2) complex, crucial for eukaryotic growth, differentiation, and metabolic regulation, presents a promising therapeutic target for various human diseases, including cancer, diabetes, and obesity. Its potential as an antifungal target is further highlighted in this study, which explores CK2's functions in C. neoformans, a key fungal meningitis pathogen. The CK2 complex in C. neoformans, comprising the Cka1 catalytic subunit and Ckb1/2 regulatory subunits, is integral to processes like growth, cell cycle, morphogenesis, stress response, drug resistance, and virulence. Our findings of CK2's role in regulating critical signaling pathways, including Hog1, Mpk1 MAPKs, cAMP/PKA, and calcium/calcineurin, underscore its importance in C. neoformans pathogenicity. This study provides valuable insights into the fungal CK2 complex, reinforcing its potential as a target for novel antifungal drug development and pointing out a promising direction for creating new antifungal agents.


Assuntos
Criptococose , Cryptococcus neoformans , Diabetes Mellitus , Meningite Fúngica , Neoplasias , Animais , Camundongos , Humanos , Caseína Quinase II/genética , Caseína Quinase II/metabolismo , Cryptococcus neoformans/metabolismo , Antifúngicos/metabolismo , Cálcio/metabolismo , Calcineurina/metabolismo , Proteômica , Transdução de Sinais , Criptococose/microbiologia , Obesidade
15.
Nat Commun ; 15(1): 192, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167422

RESUMO

High-rate production of multicarbon chemicals via the electrochemical CO2 reduction can be achieved by efficient CO2 mass transport. A key challenge for C-C coupling in high-current-density CO2 reduction is how to promote *CO formation and dimerization. Here, we report molecularly enhanced CO2-to-*CO conversion and *CO dimerization for high-rate ethylene production. Nanoconfinement of ascorbic acid by graphene quantum dots enables immobilization and redox reversibility of ascorbic acid in heterogeneous electrocatalysts. Cu nanowire with ascorbic acid nanoconfined by graphene quantum dots (cAA-CuNW) demonstrates high-rate ethylene production with a Faradaic efficiency of 60.7% and a partial current density of 539 mA/cm2, a 2.9-fold improvement over that of pristine CuNW. Furthermore, under low CO2 ratio of 33%, cAA-CuNW still exhibits efficient ethylene production with a Faradaic efficiency of 41.8%. We find that cAA-CuNW increases *CO coverage and optimizes the *CO binding mode ensemble between atop and bridge for efficient C-C coupling. A mechanistic study reveals that ascorbic acid can facilitate *CO formation and dimerization by favorable electron and proton transfer with strong hydrogen bonding.

16.
J Chem Phys ; 160(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38189606

RESUMO

Alkoxide precursors have been highlighted for depositing carbon-free films, but their use in Atomic Layer Deposition (ALD) often exhibits a non-saturated growth. This indicates no self-limiting growth due to the chain reaction of hydrolysis or ligand decomposition caused by ß-hydride elimination. In the previous study, we demonstrated that self-limiting growth of ALD can be achieved using our newly developed precursor, hafnium cyclopentadienyl tris(N-ethoxy-2,2-dimethyl propanamido) [HfCp(edpa)3]. To elucidate the growth mechanism and the role of cyclopentadienyl (Cp) ligand in a heteroleptic alkoxide precursor, herein, we compare homoleptic and heteroleptic Hf precursors consisting of N-ethoxy-2,2-dimethyl propanamido (edpa) ligands with and without cyclopentadienyl ligand-hafnium tetrakis(N-ethoxy-2,2-dimethyl propanamido) [Hf(edpa)4] and HfCp(edpa)3. We also investigate the role of a Cp ligand in growth characteristics. By substituting an alkoxide ligand with a Cp ligand, we could modify the surface reaction during ALD, preventing undesired reactions. The last remaining edpa after Hf(edpa)4 adsorption can undergo a hydride elimination reaction, resulting in surface O-H generation. In contrast, Cp remains after the HfCp(edpa)3 adsorption. Accordingly, we observe proper ALD growth with self-limiting properties. Thus, a comparative study of different ligands of the precursors can provide critical clues to the design of alkoxide precursors for obtaining typical ALD growth with a saturation behavior.

17.
Nanoscale ; 16(5): 2235-2249, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38193364

RESUMO

The electrochemical carbon dioxide (CO2) reduction reaction (CO2RR) is considered a promising technology for converting atmospheric CO2 into value-added compounds by utilizing renewable energy. The CO2RR has developed in various ways over the past few decades, including product selectivity, current density, and catalytic stability. However, its commercialization is still unsuitable in terms of economic feasibility. One of the major challenges in its commercialization is the low single-pass conversion efficiency (SPCE) of CO2, which is primarily caused by the formation of carbonate (CO32-) in neutral and alkaline electrolytes. Notably, the majority of CO2RRs take place in such media, necessitating significant energy input for CO2 regeneration. Therefore, performing the CO2RR under conditions that minimize CO32- formation to suppress reactant and electrolyte ion loss is regarded an optimal strategy for practical applications. Here, we introduce the recent progress and perspectives in the electrochemical CO2RR in acidic electrolytes, which receives great attention because of the inhibition of CO32- formation. This includes the categories of nanoscale catalytic design, microscale microenvironmental effects, and bulk scale applications in electrolyzers for zero carbon loss reactions. Additionally, we offer insights into the issue of limited catalytic durability, a notable drawback under acidic conditions and propose guidelines for further development of the acidic CO2RR.

18.
Biosens Bioelectron ; 246: 115838, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38042052

RESUMO

Stem cell technology holds immense potential for revolutionizing medicine, particularly in regenerative treatment for heart disease. The unique capacity of stem cells to differentiate into diverse cell types offers promise in repairing damaged tissues and implanting organs. Ensuring the quality of differentiated cells, essential for specific functions, demands in-depth analysis. However, this process consumes time and incurs substantial costs while invasive methods may alter stem cell features during differentiation and deplete cell numbers. To address these challenges, we propose a non-invasive strategy, using cellular respiration, to assess the quality of differentiation-induced stem cells, notably cardiovascular stem cells. This evaluation employs an electronic nose (E-Nose) and neural pattern separation (NPS). Our goal is to assess differentiation-induced cardiac stem cells (DICs) quality through E-Nose data analysis and compare it with standard commercial human cells (SCHCs). Sensitivity and specificity were evaluated by interacting SCHCs and DICs with the E-Nose, achieving over 90% classification accuracy. Employing selective combinations optimized by NPS, E-Nose successfully classified all six cell types. Consequently, the relative similarity among DICs like cardiomyocytes, endothelial cells with SCHCs was established relied on comparing response data from the E-Nose sensor without resorting to complex evaluations.


Assuntos
Técnicas Biossensoriais , Nariz Eletrônico , Humanos , Células Endoteliais , Diferenciação Celular , Células-Tronco
19.
Laryngoscope ; 134(2): 614-621, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37338090

RESUMO

OBJECTIVE: Chronic sialadenitis is associated with decreased quality of life and recurrent infections. While sialendoscopy with stenting is effective in relieving symptoms of sialadenitis, currently available stents are rigid and poorly tolerated by patients, leading to early removal and potential for adverse scarring. This study examines whether sutures can be used as a stenting material to improve patient comfort and reduce recurrence risk. METHODS: This is a retrospective cohort study of a consecutive series of adult patients with chronic sialadenitis undergoing sialendoscopy with or without suture stenting. Data were collected between 2014 and 2018 with a 3-year follow-up period ending in 2021. The primary outcome measure was recurrence of sialadenitis within 3 years of surgery. Secondary outcomes were stent dislodgement and patient-reported discomfort. RESULTS: We included 63 patients with parotid sialadenitis of whom 28 underwent suture stenting and 35 did not receive stenting after sialendoscopy. Stents were well tolerated, with a mean duration of 34.5 days, and only 2 of 28 stents (7.1%) accidentally dislodged within the first week. Suture stenting significantly reduced symptom recurrence after sialendoscopy (OR = 0.09, 95% CI 0.02-0.45, p = 0.003; 3-year sialadenitis recurrence rate: 7.1% vs. 45.7%, p = 0.005). Cox multivariate regression for clinicodemographic variables showed an HR of 0.04 (95% CI 0.01-0.19, p < 0.001) for the risk of symptom recurrence. CONCLUSIONS AND RELEVANCE: Suture stenting after sialendoscopy is low cost, available across all institutions, well-tolerated by patients, and highly efficacious in reducing risk of recurrent sialadenitis after sialendoscopy. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:614-621, 2024.


Assuntos
Parotidite , Sialadenite , Adulto , Humanos , Qualidade de Vida , Estudos Retrospectivos , Endoscopia/efeitos adversos , Endoscopia/métodos , Resultado do Tratamento , Sialadenite/cirurgia , Sialadenite/diagnóstico , Doença Crônica , Suturas
20.
J Am Heart Assoc ; 13(1): e030776, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38156546

RESUMO

BACKGROUND: Epinephrine is administered to increase coronary perfusion pressure during advanced life support and promote short-term survival. Recent cardiopulmonary resuscitation (CPR) guidelines recommend an epinephrine dosing interval of 3 to 5 minutes during resuscitation; however, scientific evidence supporting this recommendation is lacking. Therefore, we aimed to investigate the hemodynamic effects of repeated epinephrine doses during CPR by monitoring augmented blood pressure after its administration in a swine model of cardiac arrest. METHODS AND RESULTS: A secondary analysis of data from a published study was performed using a swine cardiac arrest model. The epinephrine dose was fixed at 1 mg, and the first dose of epinephrine was administered after no-flow and low-flow times of 2 minutes and 8 minutes, respectively, and subsequently administered every 4 minutes. Four cycles of dosing intervals were defined because a previous study was terminated 26 minutes after the induction of ventricular fibrillation. Augmented blood pressures and corresponding timelines were determined. Augmented blood pressure trends following cycles and the epinephrine effect duration were also monitored. Among the 140 CPR cycles, the augmented blood pressure after epinephrine administration was the highest during the first cycle of CPR and decreased gradually with further cycle repetitions. The epinephrine effect duration did not differ between repeated cycles. The maximum blood pressure was achieved 78 to 97 seconds after epinephrine administration. CONCLUSIONS: Hemodynamic augmentation with repeated epinephrine administration during CPR decreased with cycle progression. Further studies are required to develop an epinephrine administration strategy to maintain its hemodynamic effects during prolonged resuscitation.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca , Animais , Suínos , Reanimação Cardiopulmonar/métodos , Epinefrina , Parada Cardíaca/etiologia , Hemodinâmica , Fibrilação Ventricular
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