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1.
Sensors (Basel) ; 24(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38676142

RESUMO

Rheumatoid arthritis (RA) is a chronic disease, in which permanent joint deformation is largely preventable with the timely introduction of appropriate treatment strategies. However, there is no consensus for patients with RA to monitor their progress and communicate it to the rheumatologist till the condition progresses to remission. In response to this unmet need, we proposed the design of a self-measuring device based on bioelectrical impedance analysis (BIA) for regular monitoring of inflammation levels. Twenty joints of both hands were measured to monitor trends in inflammation levels. Three electrodes were used to measure two joints of each finger. A central electrode was used for two consecutive measurements. A suitable form factor for the device was proposed for the vertical placement of the hand. To ensure the stability of measurements, an air cushion was incorporated into the back of the hand, hand containers were designed on both sides, and a mobile application was designed. We conducted a convergence-assessment experiment with five air pressures to validate the consistency and convergence of bioimpedance measurements. A heuristic evaluation of the usability around the product and mobile application was conducted in parallel by six subject matter experts and validated the design. This study underscores the significance of considering patients' disease activity during intervals between hospital visits and introduces a novel approach to self-RA care.


Assuntos
Artrite Reumatoide , Impedância Elétrica , Humanos , Artrite Reumatoide/fisiopatologia , Artrite Reumatoide/diagnóstico , Desenho de Equipamento , Monitorização Fisiológica/métodos , Monitorização Fisiológica/instrumentação , Aplicativos Móveis , Feminino , Masculino , Eletrodos
2.
Sci Rep ; 14(1): 498, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177229

RESUMO

We aimed to determine the effect of optic disc tilt on deep learning-based optic disc classification. A total of 2507 fundus photographs were acquired from 2236 eyes of 1809 subjects (mean age of 46 years; 53% men). Among all photographs, 1010 (40.3%) had tilted optic discs. Image annotation was performed to label pathologic changes of the optic disc (normal, glaucomatous optic disc changes, disc swelling, and disc pallor). Deep learning-based classification modeling was implemented to develop optic-disc appearance classification models with the photographs of all subjects and those with and without tilted optic discs. Regardless of deep learning algorithms, the classification models showed better overall performance when developed based on data from subjects with non-tilted discs (AUC, 0.988 ± 0.002, 0.991 ± 0.003, and 0.986 ± 0.003 for VGG16, VGG19, and DenseNet121, respectively) than when developed based on data with tilted discs (AUC, 0.924 ± 0.046, 0.928 ± 0.017, and 0.935 ± 0.008). In classification of each pathologic change, non-tilted disc models had better sensitivity and specificity than the tilted disc models. The optic disc appearance classification models developed based all-subject data demonstrated lower accuracy in patients with the appearance of tilted discs than in those with non-tilted discs. Our findings suggested the need to identify and adjust for the effect of optic disc tilt on the optic disc classification algorithm in future development.


Assuntos
Aprendizado Profundo , Anormalidades do Olho , Glaucoma , Disco Óptico , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Disco Óptico/diagnóstico por imagem , Disco Óptico/patologia , Tomografia de Coerência Óptica/métodos , Anormalidades do Olho/patologia , Glaucoma/diagnóstico , Glaucoma/patologia
3.
Lab Chip ; 24(4): 751-763, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38193617

RESUMO

Despite significant advancements in three-dimensional (3D) cell culture technology and the acquisition of extensive data, there is an ongoing need for more effective and dependable data analysis methods. These concerns arise from the continued reliance on manual quantification techniques. In this study, we introduce a microphysiological system (MPS) that seamlessly integrates 3D cell culture to acquire large-scale imaging data and employs deep learning-based virtual staining for quantitative angiogenesis analysis. We utilize a standardized microfluidic device to obtain comprehensive angiogenesis data. Introducing Angio-Net, a novel solution that replaces conventional immunocytochemistry, we convert brightfield images into label-free virtual fluorescence images through the fusion of SegNet and cGAN. Moreover, we develop a tool capable of extracting morphological blood vessel features and automating their measurement, facilitating precise quantitative analysis. This integrated system proves to be invaluable for evaluating drug efficacy, including the assessment of anticancer drugs on targets such as the tumor microenvironment. Additionally, its unique ability to enable live cell imaging without the need for cell fixation promises to broaden the horizons of pharmaceutical and biological research. Our study pioneers a powerful approach to high-throughput angiogenesis analysis, marking a significant advancement in MPS.


Assuntos
Angiogênese , Aprendizado Profundo , Técnicas de Cultura de Células
4.
Paediatr Anaesth ; 34(3): 259-266, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38037830

RESUMO

BACKGROUND: The administration of intravenous dexamethasone increases the duration of neuraxial block and improves the quality of analgesia. However, little is known about these effects of dexamethasone on peripheral nerve blocks in children. AIMS: In this study, we aimed to investigate the benefit of intravenous dexamethasone for enhancing the effect of pudendal block on postoperative analgesia in children who underwent hypospadias surgery. METHODS: In total, 46 children aged 6-36 months who underwent hypospadias surgery were randomly allocated to either a control group (normal saline, group C) or dexamethasone group (0.5 mg/kg, group D). Pudendal block was performed before the surgery using 0.3 mL/kg of 0.225% ropivacaine on both sides. Parents were instructed to press the patient-controlled analgesia bolus button when their children's pain score was >4 points. The primary outcome measure was the time at which the first patient-controlled analgesia by proxy bolus dose was administered. The secondary outcome measures were pain score, number of patient-controlled analgesia administration by proxy bolus attempts, number of rescue analgesics required, total amount of fentanyl administered, and overall parental satisfaction. RESULTS: The time of first patient-controlled analgesia bolus administration by proxy was not different between the control and dexamethasone groups (5.6 [5.2, 8.8] h versus 6.5 [5.4, 8.1] h, hazard ratio 0.8, 95% confidence intervals 0.43 to 1.47, p = .46). There were no statistically significant differences among the secondary outcomes. CONCLUSIONS: Administration of intravenous dexamethasone did not enhance the duration of pudendal nerve block in infants and children aged 6-36 months who underwent hypospadias surgery.


Assuntos
Hipospadia , Nervo Pudendo , Humanos , Lactente , Masculino , Analgesia Controlada pelo Paciente , Anestésicos Locais , Dexametasona , Método Duplo-Cego , Hipospadia/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Pré-Escolar , Feminino
5.
Nanotechnology ; 35(10)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38061058

RESUMO

The Niobium Dioxide (NbO2) oscillator neuron has garnered significant interest because of its simple structure compared to conventional CMOS-based circuits. However, the limited on/off resistance ratio narrows the range of series resistances that satisfy the self-oscillation conditions and limits its use in large-scale synaptic arrays. In this study, we report the possibility of improving the performance of NbO2-based oscillator neuron devices through cryogenic operation. The study emphasizes two crucial parameters: the on/off resistance ratio and the oscillation amplitude, both of which are essential for accurate weighted sum classification. The data suggest that these parameters can be effectively enhanced under cryogenic conditions. In addition, we revealed that 120 K is the optimal temperature for cryogenic operation, as it represents the temperature where the on/off resistance ratio ceases to increase. As a result, we revealed that the series resistance range satisfying the self-oscillation condition in a single oscillator increases from 20 to 126 kΩ. The research also probes the maximum possible array size at each temperature. At 300 K, representation is only possible for a 5 × 5 array, but at 120 K, a 30 × 30 array can be represented as a frequency. The evidence implies that the 120 K conditions not only broaden the range of series resistors that can be connected to a single oscillator but also increases the array size, thereby representing different weighted sum currents as frequencies. The research indicates that using carefully optimized cryogenic operation could be a viable method to enhance the necessary NbO2properties for an oscillator neuron device.

6.
Biomed Pharmacother ; 168: 115776, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37924785

RESUMO

Persistent damage to liver cells leads to liver fibrosis, which is characterized by the accumulation of scar tissue in the liver, ultimately leading to cirrhosis and serious complications. Because it is difficult to reverse cirrhosis once it has progressed, the primary focus has been on preventing the progression of liver fibrosis. However, studies on therapeutic agents for liver fibrosis are still lacking. Here, we investigated that the natural dipeptide cyclic histidine-proline (CHP, also known as diketopiperazine) shows promising potential as a therapeutic agent in models of liver injury by inhibiting the progression of fibrosis through activation of the Nrf2 pathway. To elucidate the underlying biological mechanism of CHP, we used the Cellular Thermal Shift Assay (CETSA)-LC-MS/MS, a label-free compound-based target identification platform. Chloride intracellular channel protein 1 (CLIC1) was identified as a target whose thermal stability is increased by CHP treatment. We analyzed the direct interaction of CHP with CLIC1 which revealed a potential interaction between CHP and the E228 residue of CLIC1. Biological validation experiments showed that knockdown of CLIC1 mimicked the antioxidant effect of CHP. Further investigation using a mouse model of CCl4-induced liver fibrosis in wild-type and CLIC1 KO mice revealed the critical involvement of CLIC1 in mediating the effects of CHP. Taken together, our results provide evidence that CHP exerts its anti-fibrotic effects through specific binding to CLIC1. These insights into the mechanism of action of CHP may pave the way for the development of novel therapeutic strategies for fibrosis-related diseases.


Assuntos
Cloretos , Fator 2 Relacionado a NF-E2 , Humanos , Canais de Cloreto/metabolismo , Cloretos/metabolismo , Cromatografia Líquida , Cirrose Hepática/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Fenótipo , Espectrometria de Massas em Tandem
7.
Nanotechnology ; 35(2)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37827148

RESUMO

In this study, a two-dimensional electron gas (2DEG), which is a conductive layer formed at the interface of Al2O3and TiO2, was used as an electrode for resistive random access memory (RRAM) and implemented in a cell size down to 30 nm. For an RRAM device comprising W/2DEG/TiO2/W, we confirmed that the dominant switching mechanism changed from interfacial to filamentary as the cell size decreased from 500 nm to 30 nm. Through analyses of changes in forming characteristics and conduction mechanisms in the low resistive state depending on the cell size, it was identified that the 2DEG acted as an oxygen-scavenging layer of TiO2during the resistive switching process. By comparing the switching characteristics of RRAM devices with and without 2DEG for a 30 nm cell size, we confirmed that a high-performance 2DEG RRAM was realized, with highly uniform current-voltage characteristics, a low operating voltage (∼1 V), and a high on/off ratio (>102). Finally, the applicability of the proposed device to a crossbar array was validated by evaluating 1S1R operation with an NbO2-based selector. Considering the improved switching uniformity, the 2DEG RRAM shows promise for high-density memory applications.

8.
Ann Occup Environ Med ; 35: e33, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37701486

RESUMO

Background: Studies on the association between occupational stress and depression have been frequently reported. However, the cross-sectional designs of studies limited insight into causal associations. In this study, we investigated the longitudinal association between occupational stress and new-onset depression among employees in a single manufacturing plant. Methods: The annual health checkup data of employees at a manufacturing plant in Korea were collected. A total of 1,837 male employees without depression who completed a health checkup during two consecutive years were included. Occupational stress was measured using a short form of the Korea Occupational Stress Scale (KOSS-SF), and depression was assessed using a Patient Health Questionnaire-2. The association between occupational stress change over the two years and newly developed depression was investigated using two logistic regression models. Results: Across all sub-factors of KOSS-SF, employees who reported increased occupational stress had a higher risk of new-onset depression. Newly developed depression was significantly associated with job demand (odds ratio [OR]: 4.34; 95% confidence interval [CI]: 2.37-7.96), job insecurity (OR: 3.21; 95% CI: 1.89-5.48), occupational climate (OR: 3.18; 95% CI: 1.91-5.31), lack of reward (OR: 2.28; 95% CI: 1.26-4.12), interpersonal conflict (OR: 2.14; 95% CI: 1.18-3.86), insufficient job control (OR: 1.93; 95% CI: 1.05-3.56), and the organizational system (OR: 1.84; 95% CI: 1.01-3.36). Conclusions: For every sub-factor of the KOSS-SF, occupational stress increase and persistent high stress were associated with the risk of developing new-onset depression. Among the seven sub-factors, job demand had the most significant effect. Our results show that occupational stress should be managed to promote employee mental healthcare.

9.
Ann Occup Environ Med ; 35: e32, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37701492

RESUMO

Background: Although many studies have been conducted on worker fatigue and sickness absence, the association between fatigue and sickness absence is unclear in Korean workers. This study was conducted to investigate the effect of worker fatigue on future sickness absence. Methods: The study was conducted on workers who received medical check-ups at a university hospital for two consecutive years (2014-2015). During check-ups in the first year, the Fatigue Severity Scale (FSS) was used to assess fatigue levels, and during check-ups in the second year, sickness absence was surveyed to determine whether they had been absent from work due to physical or mental illness during previous 12 months. The χ2 test was used to analyze relationships between sociodemographic and occupational characteristics, fatigue levels, and sickness absence. Odds ratios (ORs) were calculated by logistic regression analysis controlled for confounding factors. Results: A total of 12,250 workers were included in the study, and 396 (3.2%) workers experienced more than one day of sickness absence during the study period. Adjusted ORs for sickness absence were 3.35 (95% confidence interval [CI]: 2.64-4.28) in the moderate-fatigue group and 6.87 (95% CI: 4.93-9.57) in the high-fatigue group versus the low-fatigue group. For men in the moderate- and high-fatigue groups, adjusted ORs for sickness absence were 3.40 (95% CI: 2.58-4.48) and 8.94 (95% CI: 6.12-13.07), and for women in the moderate- and high-fatigue groups, adjusted ORs for sickness absence were 2.93 (95% CI: 1.68-5.10) and 3.71 (95% CI: 1.84-7.49), respectively. Conclusions: Worker fatigue is associated with sickness absence during the following 12 months, and this association appears to be stronger for men than women. These results support the notion that sickness absence can be reduced by evaluating and managing work-related fatigue.

10.
Diabetologia ; 66(10): 1943-1958, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37460827

RESUMO

AIMS/HYPOTHESIS: Diabetes is associated with epigenetic modifications including DNA methylation and miRNA changes. Diabetic complications in the cornea can cause persistent epithelial defects and impaired wound healing due to limbal epithelial stem cell (LESC) dysfunction. In this study, we aimed to uncover epigenetic alterations in diabetic vs non-diabetic human limbal epithelial cells (LEC) enriched in LESC and identify new diabetic markers that can be targeted for therapy to normalise corneal epithelial wound healing and stem cell expression. METHODS: Human LEC were isolated, or organ-cultured corneas were obtained, from autopsy eyes from non-diabetic (59.87±20.89 years) and diabetic (71.93±9.29 years) donors. The groups were not statistically different in age. DNA was extracted from LEC for methylation analysis using Illumina Infinium 850K MethylationEPIC BeadChip and protein was extracted for Wnt phospho array analysis. Wound healing was studied using a scratch assay in LEC or 1-heptanol wounds in organ-cultured corneas. Organ-cultured corneas and LEC were transfected with WNT5A siRNA, miR-203a mimic or miR-203a inhibitor or were treated with recombinant Wnt-5a (200 ng/ml), DNA methylation inhibitor zebularine (1-20 µmol/l) or biodegradable nanobioconjugates (NBCs) based on polymalic acid scaffold containing antisense oligonucleotide (AON) to miR-203a or a control scrambled AON (15-20 µmol/l). RESULTS: There was significant differential DNA methylation between diabetic and non-diabetic LEC. WNT5A promoter was hypermethylated in diabetic LEC accompanied with markedly decreased Wnt-5a protein. Treatment of diabetic LEC and organ-cultured corneas with exogenous Wnt-5a accelerated wound healing by 1.4-fold (p<0.05) and 37% (p<0.05), respectively, and increased LESC and diabetic marker expression. Wnt-5a treatment in diabetic LEC increased the phosphorylation of members of the Ca2+-dependent non-canonical pathway (phospholipase Cγ1 and protein kinase Cß; by 1.15-fold [p<0.05] and 1.36-fold [p<0.05], respectively). In diabetic LEC, zebularine treatment increased the levels of Wnt-5a by 1.37-fold (p<0.01)and stimulated wound healing in a dose-dependent manner with a 1.6-fold (p<0.01) increase by 24 h. Moreover, zebularine also improved wound healing by 30% (p<0.01) in diabetic organ-cultured corneas and increased LESC and diabetic marker expression. Transfection of these cells with WNT5A siRNA abrogated wound healing stimulation by zebularine, suggesting that its effect was primarily due to inhibition of WNT5A hypermethylation. Treatment of diabetic LEC and organ-cultured corneas with NBC enhanced wound healing by 1.4-fold (p<0.01) and 23.3% (p<0.05), respectively, with increased expression of LESC and diabetic markers. CONCLUSIONS/INTERPRETATION: We provide the first account of epigenetic changes in diabetic corneas including dual inhibition of WNT5A by DNA methylation and miRNA action. Overall, Wnt-5a is a new corneal epithelial wound healing stimulator that can be targeted to improve wound healing and stem cells in the diabetic cornea. DATA AVAILABILITY: The DNA methylation dataset is available from the public GEO repository under accession no. GSE229328 ( https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE229328 ).


Assuntos
Diabetes Mellitus , MicroRNAs , Humanos , Repressão Epigenética , Proteína Wnt-5a/genética , Proteína Wnt-5a/metabolismo , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco/metabolismo , RNA Interferente Pequeno/metabolismo , Cicatrização/genética , Células Epiteliais/metabolismo
11.
Mol Ther Methods Clin Dev ; 29: 213-226, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37081854

RESUMO

In previous studies, we achieved safe and efficient in vivo hematopoietic stem cell (HSC) transduction in mobilized mice and macaques with intravenously injected helper-dependent adenovirus HDAd5/35++ vectors. These vectors are derivatives of serotype Ad5-containing CD46-affinity enhanced Ad35 fiber knob domains. Considering the impact of anti-Ad5/HDAd5/35++ neutralizing serum antibodies present in the human population, we generated HSC-retargeted HDAd6/35++ vectors derived from serotype 6. We found a lower prevalence and titers of serum anti-HDAd6/35++ in human samples compared with HDAd5/35++. HDAd6/35++ vectors efficiently transduced human and rhesus CD34+ cells in vitro. Intravenous injection of HDAd5/35++-GFP or HDAd6/35++-GFP vectors after G-CSF/AMD3100 mobilization of mice with established human hematopoiesis or human CD46 transgenic mice resulted in comparable GFP marking rates in HSCs in the bone marrow and spleen. In long-term in vivo HSC transduction and selection studies with integrating vectors, stable GFP expression in >75% of PBMCs was show for both vectors. In contrast with HDAd5/35++, undesired transduction of hepatocytes was minimal with HDAd6/35++. Furthermore, HDAd6/35++ allowed for efficient in vivo HSC transduction in Ad5-pre-immune mice. These features, together with the straightforward production of HDAd6/35++ vectors at high yield, make this new HDAd vector platform attractive for clinical translation of the in vivo approach.

13.
Opt Express ; 31(5): 7579-7588, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859887

RESUMO

To obtain the surface shape of an X-ray mirror with high precision, a differential deposition method was used instead of a direct removal method. To modify the mirror surface shape using the differential deposition method, it is necessary to coat it with a thick film, and the co-deposition method is used to suppress the increase in surface roughness. The addition of C to the Pt thin film, which is often used as an X-ray optical thin film, resulted in lower surface roughness compared with that with the Pt coating alone, and the stress change according to the thin film thickness was evaluated. Differential deposition controls the speed of the substrate during coating based on continuous motion. The stage was controlled by calculating the dwell time through deconvolution calculations based on the accurate measurement of the unit coating distribution and target shape. We successfully fabricated an X-ray mirror with high precision. This study indicated that an X-ray mirror surface could be manufactured by modifying the surface shape at a micrometer level through the coating. Changing the shape of existing mirrors can not only result in the manufacture of high-precision X-ray mirrors but also improve their performance.

14.
Mol Ther ; 31(4): 1059-1073, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36760126

RESUMO

We aim to develop an in vivo hematopoietic stem cell (HSC) gene therapy approach for persistent control/protection of HIV-1 infection based on the stable expression of a secreted decoy protein for HIV receptors CD4 and CCR5 (eCD4-Ig) from blood cells. HSCs in mice and a rhesus macaque were mobilized from the bone marrow and transduced by an intravenous injection of HSC-tropic, integrating HDAd5/35++ vectors expressing rhesus eCD4-Ig. In vivo HSC transduction/selection resulted in stable serum eCD4-Ig levels of ∼100 µg/mL (mice) and >20 µg/mL (rhesus) with half maximal inhibitory concentrations (IC50s) of 1 µg/mL measured by an HIV neutralization assay. After simian-human-immunodeficiency virus D (SHIV.D) challenge of rhesus macaques injected with HDAd-eCD4-Ig or a control HDAd5/35++ vector, peak plasma viral load levels were ∼50-fold lower in the eCD4-Ig-expressing animal. Furthermore, the viral load was lower in tissues with the highest eCD4-Ig expression, specifically the spleen and lymph nodes. SHIV.D challenge triggered a selective expansion of transduced CD4+CCR5+ cells, thereby increasing serum eCD4-Ig levels. The latter, however, broke immune tolerance and triggered anti-eCD4-Ig antibody responses, which could have contributed to the inability to eliminate SHIV.D. Our data will guide us in the improvement of the in vivo approach. Clearly, our conclusions need to be validated in larger animal cohorts.


Assuntos
Infecções por HIV , HIV-1 , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Humanos , Animais , Camundongos , Macaca mulatta , Vírus da Imunodeficiência Símia/genética , Células-Tronco Hematopoéticas , Síndrome de Imunodeficiência Adquirida dos Símios/terapia
15.
Sci Prog ; 106(1): 368504231152770, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36691679

RESUMO

Cities are vulnerable to a range of disasters that can occur simultaneously due to their complexity. Therefore, an effective disaster response plan is needed to reduce the disaster vulnerability of cities. In particular, evacuation route management is important for reducing the losses from a disaster. Efficient disaster response can be realized by searching for suitable evacuation routes and effective road network management. In this paper, we propose a disaster response framework based on a multilayered road network structure and evacuation routes based on our road network. The suggested road structure consists of three layers for the effective management of the network. An A* algorithm-based search for multiple evacuation routes under different conditions in response to an individual disaster on the configured road map provides a safe route for evacuees. As a result, the damage caused by disasters in urban areas can be ameliorated.


Assuntos
Planejamento em Desastres , Desastres
17.
Microsyst Nanoeng ; 8: 126, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36478874

RESUMO

The development of organs-on-a-chip has resulted in advances in the reconstruction of 3D cellular microenvironments. However, there remain limitations regarding applicability and manufacturability. Here, we present an injection-molded plastic array 3D universal culture platform (U-IMPACT) for various biological applications in a single platform, such as cocultures of various cell types, and spheroids (e.g., tumor spheroids, neurospheres) and tissues (e.g., microvessels). The U-IMPACT consists of three channels and a spheroid zone with a 96-well plate form factor. Specifically, organoids or spheroids (~500 µm) can be located in designated areas, while cell suspensions or cell-laden hydrogels can be selectively placed in three channels. For stable multichannel patterning, we developed a new patterning method based on capillary action, utilizing capillary channels and the native contact angle of the materials without any modification. We derived the optimal material hydrophilicity (contact angle of the body, 45-90°; substrate, <30°) for robust patterning through experiments and theoretical calculations. We demonstrated that the U-IMPACT can implement 3D tumor microenvironments for angiogenesis, vascularization, and tumor cell migration. Furthermore, we cultured neurospheres from induced neural stem cells. The U-IMPACT can serve as a multifunctional organ-on-a-chip platform for high-content and high-throughput screening.

18.
Nano Converg ; 9(1): 53, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36459274

RESUMO

This article presents a technique of scattering-type scanning near-field optical microscopy (s-SNOM) based on scanning probe microscopy as a nanoscale-resolution chemical visualization technique of the structural changes in photoresist thin films. Chemical investigations were conducted in the nanometer regime by highly concentrated near-field infrared on the sharp apex of the metal-coated atomic force microscopy (AFM) tip. When s-SNOM was applied along with Fourier transform infrared spectroscopy to characterize the extreme UV- and electron-beam (e-beam)-exposed hydrogen silsesquioxane films, line and space patterns of half-pitch 100, 200, 300, and 500 nm could be successfully visualized prior to pattern development in the chemical solutions. The linewidth and line edge roughness values of the exposed domains obtained by s-SNOM were comparable to those extracted from the AFM and scanning electron microscopy images after development. The chemical analysis capabilities provided by s-SNOM provide new analytical opportunities that are not possible with traditional e-beam-based photoresist measurement, thus allowing information to be obtained without interference from non-photoreaction processes such as wet development.

19.
Biomaterials ; 290: 121826, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36201944

RESUMO

Mesenchymal stromal cells (MSCs) continue to be proposed for use in clinical trials to treat various diseases due to their therapeutic potential to pleiotropically influence endogenous regenerative processes, such as vasculogenesis. However, the functional heterogeneity of MSCs has hampered their clinical success and poses a significant manufacturing challenge with respect to MSC quality control. Here, we evaluated and qualified a quantitative bioassay based on an enhanced-throughput, microphysiological system to measure the specific paracrine bioactivity of MSCs to stimulate vasculogenesis as a measure of MSC potency. Using this novel bioassay, MSCs derived from multiple donors at different passages were co-cultured with human umbilical vein endothelial cells (HUVECs) and exhibited significant heterogeneity in vasculogenic potency between donors and cell passage. Using our microphysiological system (MPS)-based platform, we demonstrated that variations in MSC vasculogenic bioactivity were maintained when assayed across laboratories and operators. The differences in MSC vasculogenic bioactivity were also correlated with the baseline expression of several genes involved in vasculogenesis (hepatocyte growth factor (HGF), angiopoietin-1 (ANGPT)) or the production of matricellular proteins (fibronectin (FN), insulin-like growth factor-binding protein 7 (IGFBP7)). These findings emphasize the significant functional heterogeneity of MSCs in vasculogenic bioactivity and suggest that changes in baseline gene expression of vasculogenic or matricellular protein genes during manufacturing may affect this bioactivity. The development of a reliable and functionally relevant potency assay for measuring the specific vasculogenic bioactivity of manufactured MSCs will help to reliably assure their quality when used in appropriate clinical trials.


Assuntos
Células-Tronco Mesenquimais , Humanos , Células-Tronco Mesenquimais/metabolismo , Técnicas de Cocultura , Diferenciação Celular , Células Endoteliais da Veia Umbilical Humana/metabolismo , Bioensaio , Células Cultivadas , Proliferação de Células
20.
Ann Occup Environ Med ; 34: e25, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36267359

RESUMO

Background: Many studies have been conducted on presenteeism and absenteeism, but the relationship between presenteeism and absenteeism is unclear. This study was undertaken to investigate the effect of presenteeism on future absenteeism. Methods: This study was conducted on non-white collar workers that underwent general health examinations in 2014 and 2015. We asked subjects to fill out a questionnaire about their experiences of presenteeism for the past one year in 2014. In 2015, it was checked whether the same subjects had any experience of absence from work due to injury or disease during the past year. The χ2 test was used to analyze relationships between sociodemographic and occupational characteristics, presenteeism, and absence. Odds ratios (ORs) were calculated by logistic regression analysis controlled for confounding factors. Results: A total of 12,572 workers were included in the study. For workers who experienced presenteeism, the OR for injury absence was 2.705 (95% confidence interval [CI]: 2.044-3.581), and the OR for disease absence was 4.906 (95% CI: 3.996-6.024) after adjusting for sociodemographic and occupational confounding factors. For men that experienced presenteeism, the OR for injury absence was 3.035 (95% CI: 2.258-4.081), and the OR for disease absence was 5.508 (95% CI: 4.340-6.989). For women that experienced presenteeism, the OR for injury absence was 1.322 (95% CI: 0.577-3.028), which was not significant, and the OR for disease absence was 3.629 (95% CI: 2.405-5.475). Conclusions: This study suggests that presenteeism can influence future absenteeism. The effect of presenteeism may depend on cause of absence. Men who experienced presenteeism showed greater effects on injury and disease absence than women. For women, experience of presenteeism had a significant effect on disease absence but not on injury absence.

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