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1.
Mar Pollut Bull ; 205: 116680, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38981193

RESUMO

The sedimentation of organic carbon in the Ulleung Basin, in the southwestern East Sea (Japan Sea) was investigated using radiocarbon and sterols. The accumulation rates of organic carbon and the contents of brassicasterol and dinosterol were higher on the slope than in the central basin, reflecting the surface water productivity, whereas cholesterol showed similar or higher contents in the central basin. The coprostanol concentration in surface sediments reflected the dispersion of sewage dumped in this region. The vertical distribution showed that the coprostanol concentration was the highest in the top 5-cm layer near the Korea Strait, close to one of the two dumping sites. A high coprostanol concentration was also found near the coast further north, where the content peaked at ∼10 cm depth. The vertical distribution of coprostanol helped to estimate the sediment accumulation rate at sites where radiocarbon gradient was too small or the values were too variable.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38961586

RESUMO

The development of broadband photosensors has become crucial in various fields. Indium-gallium-zinc oxide (IGZO, In:Ga:Zn = 1:1:1) phototransistors with PbS quantum dots (QDs) have shown promising features for such sensors, such as reasonable mobility, low leakage current, good photosensitivity, and low-cost fabrication. However, the instability of PbS QD/IGZO phototransistors under an air atmosphere and prolonged storage remain serious concerns. In this article, two concepts to improve the reliability of PbS QD/IGZO phototransistors were implemented. P-type doping in the PbS QD layer through oxidation allows increasing the built-in potential between IGZO and PbS QDs, leading to enhancement in photoinduced electron-hole pair creation. Second, agglomeration and fusion of a PbS QDs layer were controlled via thermal annealing, which facilitated the transport of photocreated carriers. The p-type doping and interconnection of a PbS QD layer can be achieved by deposition and subsequent thermal annealing of gallium oxide (Ga2O3) on PbS QD/IGZO stacks. The resulting Ga2O3/PbS QD/IGZO phototransistors exhibited high-performance switching characteristics under dark conditions. Notably, they showed a remarkable photoresponsivity of 196.69 ± 4.05 A/W and a detectivity of (5.47 ± 1.4) × 1012 Jones even at a long-wavelength illumination of 1550 nm. While the unpassivated PbS/IGZO phototransistor suffered serious degradation in optical performance after 2 weeks of storage, the Ga2O3/PbS QD/IGZO phototransistor demonstrated enhanced stability, maintaining high performance for over 5 weeks. These findings suggest that Ga2O3/PbS QD/IGZO phototransistors offer a feasible approach for the fabrication of large-scale active matrix broadband photosensor arrays, potentially revolutionizing optical sensing in various cutting-edge applications.

3.
Nano Lett ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557080

RESUMO

Modern semiconductor fabrication is challenged by difficulties in overcoming physical and chemical constraints. A major challenge is the wet etching of dummy gate silicon, which involves the removal of materials inside confined spaces of a few nanometers. These chemical processes are significantly different in the nanoscale and bulk. Previously, electrical double-layer formation, bubble entrapment, poor wettability, and insoluble intermediate precipitation have been proposed. However, the exact suppression mechanisms remain unclear due to the lack of direct observation methods. Herein, we investigate limiting factors for the etching kinetics of silicon with tetramethylammonium hydroxide at the nanoscale by using liquid-phase transmission electron microscopy, three-dimensional electron tomography, and first-principles calculations. We reveal suppressed chemical reactions, unstripping phenomena, and stochastic etching behaviors that have never been observed on a macroscopic scale. We expect that solutions can be suggested from this comprehensive insight into the scale-dependent limiting factors of fabrication.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38615887

RESUMO

PURPOSE: Only a subset of patients with severe emphysema qualify for lung volume reduction surgery or endobronchial valves. We previously demonstrated that stereotactic ablative radiation therapy of lung tumors reduces lung volume in treated lobes by creating localized lung fibrosis. We aimed to determine the safety and secondarily explore the efficacy of stereotactic irradiation for lung volume reduction (SILVR) over 18 months after intervention in patients with severe emphysema. METHODS AND MATERIALS: We conducted a single-arm, prospective clinical trial in eligible patients with severe emphysema treated with unilateral stereotactic ablative radiation therapy (45 Gy in 3 fractions) to a target within the most emphysematous region. The primary outcome was safety in terms of incidence of grade ≥3 adverse events, and the secondary outcome was efficacy. RESULTS: Eight patients received the intervention. Median (range) baseline characteristics were age 73 years (63-78); forced expiratory volume in 1 second percent of predicted value (FEV1%) 28.5% (19.0-42.0); diffusing capacity of the lungs for carbon monoxide percent of predicted value 40% (24.0-67.0); and body mass index, airflow obstruction, dyspnea, and exercise capacity (BODE) index 5.5 (5-9). The incidence of grade ≥3 adverse events was 3 of 8 (37.5%). The relative change in target lobe volume was -23.1% (-1.6 to -41.5) and -26.5% (-20.6 to -40.8) at 6 and 18 months, respectively. The absolute ΔFEV1% was greater in patients with a BODE index ≤5 versus ≥6 (+12.0% vs -2.0%). The mean baseline lung density (in Hounsfield units, reflecting the amount of preserved parenchyma) within the intermediate dose volume (V60BED3) correlated with the absolute change in target lobe volume at 18 months. CONCLUSIONS: SILVR appears to be safe, with a signal for efficacy as a novel therapeutic alternative for patients with severe emphysema. SILVR may be most safe and effective in patients with a lower BODE index and/or less parenchymal destruction.

5.
Mar Pollut Bull ; 200: 116065, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38286087

RESUMO

It is crucial to establish appropriate background concentrations to discern heavy metal pollution in the marine environment. In this study, we analyzed heavy metals in deep-sea sediment cores to determine regional background concentrations at the East-Sea Byeong Ocean dumping site. The vertical profiles of heavy metals were categorized into three groups based on their contamination characteristics, and regional background levels for 12 metals were determined using pre-1900 averages. The enrichment factor, contamination factor, and pollution load index, calculated using regional background concentrations, indicated significant contamination by Cr, Co, Cu, Zn, Cd, Hg, and Pb during the ocean dumping period. These results differ from those obtained using global average concentrations. This underscores the importance of considering regional characteristics to minimize the risk of misinterpreting anthropogenic impacts. The approach based on local information is considered useful when sediment quality guidelines are absent or inapplicable.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Sedimentos Geológicos , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , República da Coreia , Oceanos e Mares , Medição de Risco
6.
Diabetes Metab J ; 48(1): 1-18, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38173375

RESUMO

Mitochondrial stress and the dysregulated mitochondrial unfolded protein response (UPRmt) are linked to various diseases, including metabolic disorders, neurodegenerative diseases, and cancer. Mitokines, signaling molecules released by mitochondrial stress response and UPRmt, are crucial mediators of inter-organ communication and influence systemic metabolic and physiological processes. In this review, we provide a comprehensive overview of mitokines, including their regulation by exercise and lifestyle interventions and their implications for various diseases. The endocrine actions of mitokines related to mitochondrial stress and adaptations are highlighted, specifically the broad functions of fibroblast growth factor 21 and growth differentiation factor 15, as well as their specific actions in regulating inter-tissue communication and metabolic homeostasis. Finally, we discuss the potential of physiological and genetic interventions to reduce the hazards associated with dysregulated mitokine signaling and preserve an equilibrium in mitochondrial stress-induced responses. This review provides valuable insights into the mechanisms underlying mitochondrial regulation of health and disease by exploring mitokine interactions and their regulation, which will facilitate the development of targeted therapies and personalized interventions to improve health outcomes and quality of life.


Assuntos
Doenças Metabólicas , Qualidade de Vida , Humanos , Mitocôndrias/metabolismo , Doenças Metabólicas/terapia , Doenças Metabólicas/metabolismo , Transdução de Sinais
7.
Small ; 20(11): e2305758, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37936297

RESUMO

Recently, sulfide-based all-solid-state batteries (ASSBs) have attracted great attention because of their excellent safety and high energy density. However, by-products formed from side-reactions between the oxide-based cathodes and sulfide-based solid electrolytes (SEs) increase the interfacial resistance and degrade the cell performance. Suppression of this interfacial resistance is thus critical. In this study, the extraordinarily high stability of the cathode/SE interface is discovered when a Li10 SnP2 S12 (LSnPS) is applied to a cathode buffer layer. The electrochemical properties of the cathode interface at high potential are improved by synthesizing a core-shell structure cathode using LSnPS. The synthesized LSnPS is uniformly coated on a Li2 ZrO3 -coated LiNi0.8 Co0.1 Mn0.1 O2 (LZO-NCM) surface using the cost-efficient mechano-fusion method. The ASSB with LSnPS-coated LZO-NCM as the cathode and Li6 PS5 Cl (argyrodite, LPSCl) as the SE exhibited a capacity of 192 mAh g-1 and excellent cycle retention of ≈75% after 500 charge/discharge cycles. In addition, the degradation mechanism at the cathode/SE interface is investigated. The results indicated that LSnPS stabilizes the interface between NCM and argyrodite, thereby inhibiting the decomposition of the SE. This technology is expected to contribute to the commercialization of cathode materials for sulfide-based ASSBs due to its enhanced cycle performance, low-cost material application, and eco-friendly process.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38082962

RESUMO

Blood pressure (BP) is a critical vital sign that hypertensive patients regularly measure. In this study, we propose a novel BP estimation framework to distill the knowledge from a multi-modal model to a uni-modal BP estimation model through teacher-student training. The multi-modal BP estimation model consists of three components: first, a gated recurrent unit network that generates features from photoplethysmogram, electrocardiogram, age, height, and weight; second, an attention mechanism that integrates each feature into joint embeddings; and third, a regression layer that estimates BP from the joint embeddings. The uni-modal BP estimation model has similar components to the multi-modal model but uses only PPG signal. BP is predicted by the embeddings extracted from the uni-modal model, and these embeddings are trained to be as similar as possible to the joint embeddings extracted from the multi-modal model. The proposed method demonstrates absolute prediction errors of 5.24±6.41 and 3.49±3.85 mmHg for systolic blood pressure and diastolic blood pressure in the MIMIC-III dataset, satisfying the AAMI standard.


Assuntos
Determinação da Pressão Arterial , Fotopletismografia , Humanos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Fotopletismografia/métodos , Eletrocardiografia , Estudantes
9.
RSC Adv ; 13(48): 33918-33928, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38020009

RESUMO

Multienzyme systems are essential for utilizing di-, oligo-, and polysaccharides as fuels in enzymatic fuel cells effectively. However, the transfer of electrons generated by one enzymatic reaction in a multienzyme cascade at the electrode may be impeded by other enzymes, potentially hindering the overall efficiency. In this study, carbon paper was first modified by incorporating single-walled carbon nanotubes (SWCNTs) and gold nanoparticles (AuNPs) sequentially. Subsequently, glucose oxidase (GOx) and a trehalase-gelatin mixture were immobilized separately on the nanostructured carbon paper via layer-by-layer adsorption to mitigate the electron transfer hindrance caused by trehalase. The anode was first fabricated by immobilizing GOx and trehalase on the modified carbon paper, and the cathode was then fabricated by immobilizing bilirubin oxidase on the nanostructured electrode. The SWCNTs and AuNPs were distributed adequately on the electrode surface, which improved the electrode performance, as demonstrated by electrochemical and morphological analyses. An enzymatic fuel cell was assembled and tested using trehalose as the fuel, and a maximum power density of 23 µW cm-2 was obtained at a discharge current density of 60 µA cm-2. The anode exhibited remarkable reusability and stability.

10.
Mar Pollut Bull ; 196: 115584, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37774462

RESUMO

Between 1999 and 2009, 344,000 m3 of red mud was released into the red mud dumping zone in the East Sea-Byeong ocean dumping site in South Korea. This study aimed to assess the impacts before and after the 2010 red mud dumping ban. We quantified total Cr concentrations by depth from core sediment samples at the red mud dumping station and evaluated benthic communities in 2004, 2009, 2012, 2017, and 2019. At the dumping station DB-085, the Cr content in the upper layer (0-10 cm) exceeded the effect range median criteria in all study years and decreased with time. Geochemical fraction studies using sequential extraction methods from core sediment samples in 2004, 2009, and 2017 showed high ratios of non-residual fractions (anthropogenic inputs), indicating persistent potential long-term risk after the 2010 ban. Additionally, we confirmed that Thyasira tokunagai, an opportunistic and contamination-stress-resistant species, dominated the study station.


Assuntos
Bivalves , Cromo , Animais , Cromo/análise , Óxido de Alumínio/química , Monitoramento Ambiental/métodos , Oceanos e Mares
11.
Mar Pollut Bull ; 193: 115205, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37352800

RESUMO

From 1991 to 2021, 16 categories of land-based waste, totaling 131,400,000 m3, were dumped at three sites in Korea. The concentration of heavy metals varied by waste type, with organic sludge showing higher levels than liquid waste. While wastewater treatment sludge was the most commonly discarded waste, the quantity and types of waste disposed of varied by site. Before the 2015 ban on ocean dumping, 62,330 tons of heavy metals were introduced, including zinc, copper, chromium, lead, arsenic, cadmium, and mercury in descending order of frequency. In each heavy metal category, the portion of land-based waste varied by dumping site. Compared to heavy metals from atmospheric deposition, anthropogenic heavy metal input from dumping was up to 141 times higher for copper. This study serves as a reference for estimating the impact of pollutants from dumped waste.


Assuntos
Arsênio , Metais Pesados , Cobre/análise , Esgotos , Metais Pesados/análise , Arsênio/análise , Oceanos e Mares , Monitoramento Ambiental
12.
Sci Rep ; 13(1): 9311, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37291140

RESUMO

Recently, several studies have proposed methods for measuring cuffless blood pressure (BP) using finger photoplethysmogram (PPG) signals. This study presents a new BP estimation system that measures PPG signals under progressive finger pressure, making the system relatively robust to errors caused by finger position when using the cuffless oscillometric method. To reduce errors caused by finger position, we developed a sensor that can simultaneously measure multi-channel PPG and force signals in a wide field of view (FOV). We propose a deep-learning-based algorithm that can learn to focus on the optimal PPG channel from multi channel PPG using an attention mechanism. The errors (ME ± STD) of the proposed multi channel system were 0.43±9.35 mmHg and 0.21 ± 7.72 mmHg for SBP and DBP, respectively. Through extensive experiments, we found a significant performance difference depending on the location of the PPG measurement in the BP estimation system using finger pressure.


Assuntos
Determinação da Pressão Arterial , Aprendizado Profundo , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Fotopletismografia/métodos , Dedos , Análise de Onda de Pulso
13.
Tissue Barriers ; 11(3): 2110798, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-35959954

RESUMO

The glomerular basement membrane (GBM) is an important tissue structure in kidney function. It is the membrane through which filtrate and solutes must pass to reach the nephron tubules. This review focuses on the spatial location of the main extracellular matrix components of the GBM. It also attempts to explain this organization in terms of their synthesis, transport, and loss. The picture that emerges is that the collagen IV and laminin content of GBM are in a very slow dynamic disequilibrium, leading to GBM thickening with age, and in contrast, some heparan sulfate proteoglycans are in a dynamic equilibrium with a very rapid turnover (i.e. half-life measured in ~hours) and flow direction against the flow of filtrate. The highly rapid heparan sulfate turnover may serve several roles, including an unclogging mechanism for the GBM, compressive stiffness of the GBM fiber network, and/or enabling podocycte-endothelial crosstalk against the flow of filtrate.


Assuntos
Membrana Basal Glomerular , Proteoglicanas de Heparan Sulfato , Heparitina Sulfato , Laminina , Néfrons
14.
MedEdPORTAL ; 18: 11284, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36524099

RESUMO

Introduction: Names are a reflection of identity and often have personal meaning. The chronic mispronunciation of names can undermine one's identity and be experienced as a microaggression. This workshop aims to provide historical context for names as well as resources for correct name pronunciation. Methods: We developed a 60-minute interactive virtual workshop with didactics, small-group sharing of personal experiences, and case discussions. We used an anonymous postworkshop survey to evaluate workshop effectiveness. Results: We presented the workshop at one local academic conference and two local educational conferences to learners of all levels from medical students to faculty. We collected postworkshop survey results from 78 participants of diverse racial and ethnic backgrounds. Participants reported learning historical context, ways to ask about correct name pronunciation, correcting name mispronunciation, documenting pronunciation, and sources for applications to practice. The main barriers to implementing workshop lessons included personal and structural factors. Discussion: This workshop effectively fills an educational gap by addressing the importance of correct name pronunciation in order to provide a more inclusive environment for clinicians and patients alike.


Assuntos
Estudantes de Medicina , Humanos , Inquéritos e Questionários
15.
Am J Case Rep ; 23: e937902, 2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36435962

RESUMO

BACKGROUND Splenosis refers to autotransplantation of splenic tissue after splenic injury or splenectomy, most frequently occurring in the abdominal and pelvic cavities. Thoracic splenosis is a rare condition associated with a history of simultaneous rupture of the spleen and diaphragm resulting from trauma. To the best of our knowledge, only a limited number of cases have been reported for combined intrathoracic and abdominal splenosis. CASE REPORT We present a case of a 50-year-old man with a history of splenectomy and left nephrectomy 15 years ago due to an accident, who had experienced chest pain for the past month. A 1-cm focal pleural thickening in the left posterior pleura was revealed on the chest computed tomography (CT) scan. We found this to be suspicious for a solitary fibrous tumor. Based on this information, surgery was performed for tumor removal, and the pathologic examination confirmed splenic tissues. The patient was then discharged without any complications. Further abdominopelvic CT showed several contrast-enhanced lesions, suggestive of intraperitoneal splenosis. CONCLUSIONS We would like to emphasize the importance of thorough history-taking to avoid misdiagnosis and unnecessary procedures with respect to the rarity of splenosis. Moreover, appropriate use of diagnostic tools, including radionuclide imaging studies, is recommended to establish an accurate diagnosis of thoracic splenosis.


Assuntos
Esplenose , Masculino , Humanos , Pessoa de Meia-Idade , Esplenose/diagnóstico por imagem , Esplenose/cirurgia , Abdome , Tórax/diagnóstico por imagem , Tórax/patologia , Esplenectomia/efeitos adversos
16.
Materials (Basel) ; 15(17)2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36079327

RESUMO

In this research, the moisture diffusion model for concrete was inversely estimated using artificial neural network (ANN) and the data collected from virtual experiments. In addition, the moisture distribution was predicted using the ANN model in numerical analysis. For inverse estimation, virtual experimental data were used. The virtual experimental data were generated by adding noise to the moisture distribution obtained by a numerical simulation using a known moisture diffusion model. ANNs of two architectures were used in the inverse estimation. For performance test, the inversely estimated ANN model and the known moisture diffusion model were compared. The predicted humidity distribution using the ANN and virtual experiment data were also compared. The inversely estimated ANN model was in a good agreement with the known moisture diffusion model used for the virtual experiment.

17.
Exp Mol Med ; 54(7): 932-945, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35804190

RESUMO

Genetic variations in mitoribosomal subunits and mitochondrial transcription factors are related to type 2 diabetes. However, the role of islet mitoribosomes in the development of type 2 diabetes has not been determined. We investigated the effects of the mitoribosomal gene on ß-cell function and glucose homeostasis. Mitoribosomal gene expression was analyzed in datasets from the NCBI GEO website (GSE25724, GSE76894, and GSE76895) and the European Nucleotide Archive (ERP017126), which contain the transcriptomes of type 2 diabetic and nondiabetic organ donors. We found deregulation of most mitoribosomal genes in islets from individuals with type 2 diabetes, including partial downregulation of CRIF1. The phenotypes of haploinsufficiency in a single mitoribosomal gene were examined using ß-cell-specific Crif1 (Mrpl59) heterozygous-deficient mice. Crif1beta+/- mice had normal glucose tolerance, but their islets showed a loss of first-phase glucose-stimulated insulin secretion. They also showed increased ß-cell mass associated with higher expression of Reg family genes. However, Crif1beta+/- mice showed earlier islet failure in response to high-fat feeding, which was exacerbated by aging. Haploinsufficiency of a single mitoribosomal gene predisposes rodents to glucose intolerance, which resembles the early stages of type 2 diabetes in humans.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Ilhotas Pancreáticas , Animais , Proteínas de Ciclo Celular/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Camundongos , Ribossomos Mitocondriais/metabolismo
18.
Clin Exp Otorhinolaryngol ; 15(3): 220-229, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35413171

RESUMO

OBJECTIVES: Hyaluronan synthase 1 (HAS1) is a membrane-bound protein that is abundant in the epidermis and dermis, and it is important for skin function. However, its association with hearing loss has not yet been studied. Herein, we sought to evaluate the potential contribution of HAS1: c.1082G>A to genetic hearing loss. METHODS: We used whole-exome sequencing to analyze blood DNA samples of six patients of a family with autosomal dominant familial late-onset progressive hearing loss, which was revealed to be related to a variant of the HAS1 gene. Confirmatory Sanger sequencing was performed with samples from 10 members. A missense variant was detected in HAS1 (c.1082 G>A, p.Cys361Tyr). In silico analyses predicted this variant to result in the functional loss of HAS1. Immunostaining was conducted using wild-type mouse samples to verify HAS1 expression. RESULTS: Has1 was detected in an otocyst at E10.5. In the pup, Has1 expression was localized in the stria vascularis (SV), hair cells, supporting cells of the organ of Corti, and some spiral ganglion neurons. SV marginal cells markedly expressed Has1 in the adult stage. The hearing threshold in the Has1-depleted condition was investigated by accessing the International Mouse Phenotyping Consortium's Auditory Brainstem Response (ABR) data. ABR of Has1 knock-out mice showed threshold elevations at 6, 12, and 18 kHz in young male adults. CONCLUSION: HAS1 may have a close relationship with auditory function and genetic hearing loss. Further investigation is needed to reveal the precise role of HAS1 in the auditory system. HAS1 is a candidate gene for future hereditary hearing loss genetic testing.

19.
J Cachexia Sarcopenia Muscle ; 13(3): 1785-1799, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35306755

RESUMO

BACKGROUND: Mitochondrial oxidative phosphorylation (OxPhos) is a critical regulator of skeletal muscle mass and function. Although muscle atrophy due to mitochondrial dysfunction is closely associated with bone loss, the biological characteristics of the relationship between muscle and bone remain obscure. We showed that muscle atrophy caused by skeletal muscle-specific CR6-interacting factor 1 knockout (MKO) modulates the bone marrow (BM) inflammatory response, leading to low bone mass. METHODS: MKO mice with lower muscle OxPhos were fed a normal chow or high-fat diet and then evaluated for muscle mass and function, and bone mineral density. Immunophenotyping of BM immune cells was also performed. BM transcriptomic analysis was used to identify key factors regulating bone mass in MKO mice. To determine the effects of BM-derived CXCL12 (C-X-C motif chemokine ligand 12) on regulation of bone homeostasis, a variety of BM niche-resident cells were treated with recombinant CXCL12. Vastus lateralis muscle and BM immune cell samples from 14 patients with hip fracture were investigated to examine the association between muscle function and BM inflammation. RESULTS: MKO mice exhibited significant reductions in both muscle mass and expression of OxPhos subunits but increased transcription of mitochondrial stress response-related genes in the extensor digitorum longus (P < 0.01). MKO mice showed a decline in grip strength and a higher drop rate in the wire hanging test (P < 0.01). Micro-computed tomography and von Kossa staining revealed that MKO mice developed a low mass phenotype in cortical and trabecular bone (P < 0.01). Transcriptomic analysis of the BM revealed that mitochondrial stress responses in skeletal muscles induce an inflammatory response and adipogenesis in the BM and that the CXCL12-CXCR4 (C-X-C chemokine receptor 4) axis is important for T-cell homing to the BM. Antagonism of CXCR4 attenuated BM inflammation and increased bone mass in MKO mice. In humans, patients with low body mass index (BMI = 17.2 ± 0.42 kg/m2 ) harboured a larger population of proinflammatory and cytotoxic senescent T-cells in the BMI (P < 0.05) and showed reduced expression of OxPhos subunits in the vastus lateralis, compared with controls with a normal BMI (23.7 ± 0.88 kg/m2 ) (P < 0.01). CONCLUSIONS: Defects in muscle mitochondrial OxPhos promote BM inflammation in mice, leading to decreased bone mass. Muscle mitochondrial dysfunction is linked to BM inflammatory cytokine secretion via the CXCL12-CXCR4 signalling axis, which is critical for inducing low bone mass.


Assuntos
Medula Óssea , Músculo Esquelético , Animais , Medula Óssea/patologia , Humanos , Inflamação/metabolismo , Masculino , Camundongos , Músculo Esquelético/patologia , Atrofia Muscular/patologia , Microtomografia por Raio-X
20.
ACS Appl Mater Interfaces ; 14(2): 3008-3017, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35000384

RESUMO

Ultraviolet to infrared broadband spectral detection capability is a technological challenge for sensing materials being developed for high-performance photodetection. In this work, we stacked 9 nm-thick tellurium oxide (TeOx) and 8 nm-thick InGaSnO (IGTO) into a heterostructure at a low temperature of 150 °C. The superior photoelectric characteristics we achieved benefit from the intrinsic optical absorption range (300-1500 nm) of the hexagonal tellurium (Te) phase in the TeOx film, and photoinduced electrons are driven effectively by band alignment at the TeOx/IGTO interface under illumination. A photosensor based on our optimized heterostructure exhibited a remarkable detectivity of 1.6 × 1013 Jones, a responsivity of 84 A/W, and a photosensitivity of 1 × 105, along with an external quantum efficiency of 222% upon illumination by blue light (450 nm). Simultaneously, modest detection properties (responsivity: ∼31 A/W, detectivity: ∼6 × 1011 Jones) for infrared irradiation at 970 nm demonstrate that this heterostructure can be employed as a broadband phototransistor. Furthermore, its low-temperature processability suggests that our proposed concept might be used to design array optoelectronic devices for wide band detection with high sensitivity, flexibility, and stability.

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