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1.
Nature ; 614(7946): 88-94, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36653458

RESUMO

Two-dimensional (2D) materials and their heterostructures show a promising path for next-generation electronics1-3. Nevertheless, 2D-based electronics have not been commercialized, owing mainly to three critical challenges: i) precise kinetic control of layer-by-layer 2D material growth, ii) maintaining a single domain during the growth, and iii) wafer-scale controllability of layer numbers and crystallinity. Here we introduce a deterministic, confined-growth technique that can tackle these three issues simultaneously, thus obtaining wafer-scale single-domain 2D monolayer arrays and their heterostructures on arbitrary substrates. We geometrically confine the growth of the first set of nuclei by defining a selective growth area via patterning SiO2 masks on two-inch substrates. Owing to substantial reduction of the growth duration at the micrometre-scale SiO2 trenches, we obtain wafer-scale single-domain monolayer WSe2 arrays on the arbitrary substrates by filling the trenches via short growth of the first set of nuclei, before the second set of nuclei is introduced, thus without requiring epitaxial seeding. Further growth of transition metal dichalcogenides with the same principle yields the formation of single-domain MoS2/WSe2 heterostructures. Our achievement will lay a strong foundation for 2D materials to fit into industrial settings.

2.
Nature ; 614(7946): 81-87, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36725999

RESUMO

Micro-LEDs (µLEDs) have been explored for augmented and virtual reality display applications that require extremely high pixels per inch and luminance1,2. However, conventional manufacturing processes based on the lateral assembly of red, green and blue (RGB) µLEDs have limitations in enhancing pixel density3-6. Recent demonstrations of vertical µLED displays have attempted to address this issue by stacking freestanding RGB LED membranes and fabricating top-down7-14, but minimization of the lateral dimensions of stacked µLEDs has been difficult. Here we report full-colour, vertically stacked µLEDs that achieve, to our knowledge, the highest array density (5,100 pixels per inch) and the smallest size (4 µm) reported to date. This is enabled by a two-dimensional materials-based layer transfer technique15-18 that allows the growth of RGB LEDs of near-submicron thickness on two-dimensional material-coated substrates via remote or van der Waals epitaxy, mechanical release and stacking of LEDs, followed by top-down fabrication. The smallest-ever stack height of around 9 µm is the key enabler for record high µLED array density. We also demonstrate vertical integration of blue µLEDs with silicon membrane transistors for active matrix operation. These results establish routes to creating full-colour µLED displays for augmented and virtual reality, while also offering a generalizable platform for broader classes of three-dimensional integrated devices.

3.
Nature ; 578(7793): 75-81, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32025010

RESUMO

Complex-oxide materials exhibit a vast range of functional properties desirable for next-generation electronic, spintronic, magnetoelectric, neuromorphic, and energy conversion storage devices1-4. Their physical functionalities can be coupled by stacking layers of such materials to create heterostructures and can be further boosted by applying strain5-7. The predominant method for heterogeneous integration and application of strain has been through heteroepitaxy, which drastically limits the possible material combinations and the ability to integrate complex oxides with mature semiconductor technologies. Moreover, key physical properties of complex-oxide thin films, such as piezoelectricity and magnetostriction, are severely reduced by the substrate clamping effect. Here we demonstrate a universal mechanical exfoliation method of producing freestanding single-crystalline membranes made from a wide range of complex-oxide materials including perovskite, spinel and garnet crystal structures with varying crystallographic orientations. In addition, we create artificial heterostructures and hybridize their physical properties by directly stacking such freestanding membranes with different crystal structures and orientations, which is not possible using conventional methods. Our results establish a platform for stacking and coupling three-dimensional structures, akin to two-dimensional material-based heterostructures, for enhancing device functionalities8,9.

4.
Nat Mater ; 22(12): 1470-1477, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38012388

RESUMO

Three-dimensional (3D) hetero-integration technology is poised to revolutionize the field of electronics by stacking functional layers vertically, thereby creating novel 3D circuity architectures with high integration density and unparalleled multifunctionality. However, the conventional 3D integration technique involves complex wafer processing and intricate interlayer wiring. Here we demonstrate monolithic 3D integration of two-dimensional, material-based artificial intelligence (AI)-processing hardware with ultimate integrability and multifunctionality. A total of six layers of transistor and memristor arrays were vertically integrated into a 3D nanosystem to perform AI tasks, by peeling and stacking of AI processing layers made from bottom-up synthesized two-dimensional materials. This fully monolithic-3D-integrated AI system substantially reduces processing time, voltage drops, latency and footprint due to its densely packed AI processing layers with dense interlayer connectivity. The successful demonstration of this monolithic-3D-integrated AI system will not only provide a material-level solution for hetero-integration of electronics, but also pave the way for unprecedented multifunctional computing hardware with ultimate parallelism.

5.
Clin Nephrol ; 97(2): 70-77, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34448695

RESUMO

INTRODUCTION: The incidence of fractures is much higher in patients with chronic kidney disease, especially those on hemodialysis (HD). Denosumab is known to treat osteoporosis. However, no exact guideline exists for treatment with denosumab in patients, especially those with diabetes. This study analyzed the effect of denosumab in HD patients with or without diabetes. MATERIALS AND METHODS: Dual-energy X-ray absorptiometry was performed in 89 HD patients: 42 were diagnosed with osteoporosis. 33 patients were treated with denosumab. An observational retrospective analysis was conducted in 25 HD patients whose follow-up biomarkers were measured at 6 months after denosumab treatment. FINDINGS: Bone mineral density (BMD) of lumbar spine (LS) and femur neck (FN) were largely improved (+3.40% and 4.96%, respectively) 1 year after the treatment. The T-scores were also improved. Both bone turnover markers were significantly decreased 6 months after treatment; the levels of C-terminal telopeptide (CTX) and bone-specific alkaline phosphatase (bsALP) were decreased by -1.04 ± 1.24 ng/mL (p < 0.001) and -35.72 ± 36.07 IU/L (p < 0.001), respectively. The response was significantly different between the diabetes and non-diabetes group. The increase in LS BMD was significantly lower in the diabetes group than in the non-diabetes group (0.02 ± 0.03 vs. 0.07 ± 0.02, p = 0.02). Decrease in CTX, but not in bsALP, was also lower in the diabetes group compared to the non-diabetes group (-0.58 ± 0.70 vs. -1.55 ± 1.12, p = 0.03). Pretreatment with calcium and calcitriol prevented symptomatic hypocalcemia except in 1 case. CONCLUSION: Denosumab improved bone density and osteoclastic activity in HD patients, with a lower response in patients with diabetes.


Assuntos
Conservadores da Densidade Óssea , Diabetes Mellitus , Biomarcadores , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Remodelação Óssea , Denosumab/efeitos adversos , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Humanos , Diálise Renal , Estudos Retrospectivos
6.
J Korean Med Sci ; 37(26): e204, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35790206

RESUMO

Despite that clinical trials have been examining the safety profile of coronavirus disease 2019 (COVID-19) vaccines, there are concerns about long-term side effects as the number of vaccinations increases. Herein, we report a case of new-onset renal-limited anti-myeloperoxidase (MPO) antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis after booster vaccination with the mRNA 1273 (Moderna) vaccine. A 72-year-old woman with no specific past history, and who had a normal renal function, developed ANCA-associated vasculitis following heterologous booster with mRNA1273 (Moderna) vaccine. After a kidney biopsy, she was diagnosed with ANCA-associated pauci-immune crescentic glomerulonephritis. Her renal function and constitutional symptoms have been improved with treatment with plasmapheresis, intravenous cyclophosphamide and steroid pulse therapy (intravenous 500 mg of methylprednisolone sodium succinate for 3 days) followed by a reduced steroid regimen.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , COVID-19 , Glomerulonefrite , Idoso , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/etiologia , Anticorpos Anticitoplasma de Neutrófilos , Feminino , Glomerulonefrite/patologia , Humanos , Vacinação/efeitos adversos
7.
Nat Mater ; 18(6): 550-560, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31114063

RESUMO

Hybrid heterostructures are essential for functional device systems. The advent of 2D materials has broadened the material set beyond conventional 3D material-based heterostructures. It has triggered the fundamental investigation and use in applications of new coupling phenomena between 3D bulk materials and 2D atomic layers that have unique van der Waals features. Here we review the state-of-the-art fabrication of 2D and 3D heterostructures, present a critical survey of unique phenomena arising from forming 3D/2D interfaces, and introduce their applications. We also discuss potential directions for research based on these new coupled architectures.

8.
Arterioscler Thromb Vasc Biol ; 35(1): 237-42, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25324574

RESUMO

OBJECTIVE: Matrix gla protein is a vitamin K-dependent inhibitor of medial arterial calcification whose synthesis and activity are blocked by warfarin. Warfarin induces arterial calcification in experimental models, but whether this occurs in humans is unclear. This was addressed by examining breast arterial calcification, which is exclusively medial and easily identified on mammograms. APPROACH AND RESULTS: Screening mammograms from women with current, past, or future warfarin use were examined for the presence of arterial calcification and compared with mammograms obtained in untreated women matched for age and diabetes mellitus. Women with a serum creatinine >2.0 mg/dL or a history of end-stage renal disease were excluded. In 451 women with mammograms performed after ≥1 month of warfarin therapy, the prevalence of arterial calcification was 50% greater than in 451 untreated women (39.0% versus 25.9%; P<0.0001). However, in 159 mammograms performed before warfarin therapy, the prevalence of arterial calcification was not increased (26.4% versus 25.8%). The increased prevalence varied with duration of treatment, from 25.0% for <1 year to 74.4% for >5 years. In a multivariable logistic model, only age and duration of warfarin, but not the period of time after stopping warfarin, were significant determinants of arterial calcification in women with current or past warfarin use. CONCLUSIONS: The prevalence of breast arterial calcification is increased in women with current or past warfarin use independent of other risk factors and conditions predating warfarin use. This effect appears to be cumulative and may be irreversible.


Assuntos
Anticoagulantes/efeitos adversos , Doenças Mamárias/induzido quimicamente , Calcificação Vascular/induzido quimicamente , Varfarina/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Doenças Mamárias/diagnóstico por imagem , Doenças Mamárias/epidemiologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Esquema de Medicação , Feminino , Georgia/epidemiologia , Humanos , Modelos Logísticos , Mamografia , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Fatores de Risco , Fatores de Tempo , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/epidemiologia , Varfarina/administração & dosagem
9.
Arterioscler Thromb Vasc Biol ; 35(2): 439-47, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25477344

RESUMO

OBJECTIVE: The histopathology of peripheral arterial disease and the accompanying calcification are poorly defined, and it is not known whether this varies according to different risk factors. APPROACH AND RESULTS: Sections from 176 upper and lower leg arteries were examined histologically in specimens from amputations of 60 patients with peripheral arterial disease, of whom 58% had diabetes mellitus, 35% had end-stage renal disease, and 48% had a history of smoking. The most common findings were calcification of the media (72% of arteries) and intimal thickening without lipid (68% of arteries), with the presence of atheromas in only 23% of arteries. Intimal calcification occurred in 43% and was generally much less extensive than medial calcification. Nonatheromatous intimal thickening was frequently severe, resulting in complete occlusion in some vessels. The absence of lipid and macrophages was confirmed by staining with oil red O and staining for CD68. Other than a greater prevalence and severity of medial calcification in end-stage renal disease, the findings did not differ between diabetics, patients with end-stage renal disease, or smokers. CONCLUSIONS: The results indicate that the majority of arteries in patients with peripheral arterial disease have a vascular lesion that is distinct from atherosclerosis, suggesting a different pathogenesis. This pattern does not differ substantially between patients with different risk factors for peripheral arterial disease. The bulk of vascular calcification in the lower extremities is medial rather than intimal.


Assuntos
Extremidade Inferior/irrigação sanguínea , Doença Arterial Periférica/epidemiologia , Doença Arterial Periférica/patologia , Túnica Média/patologia , Calcificação Vascular/epidemiologia , Calcificação Vascular/patologia , Amputação Cirúrgica , Artérias/patologia , Aterosclerose/epidemiologia , Aterosclerose/patologia , Diabetes Mellitus/epidemiologia , Humanos , Falência Renal Crônica/epidemiologia , Doença Arterial Periférica/cirurgia , Placa Aterosclerótica , Prevalência , Fatores de Risco , Índice de Gravidade de Doença , Fumar/efeitos adversos , Fumar/epidemiologia , Túnica Íntima/patologia , Calcificação Vascular/cirurgia
10.
Vasc Med ; 20(6): 527-33, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26324151

RESUMO

The presence of bone tissue in calcified arteries may provide insights into the pathophysiology and potential reversibility of calcification, but the prevalence, distribution, and determinants of bone and osteoclasts in calcified arteries are unknown. Specimens of 386 arteries from lower limb amputations in 108 patients were examined retrospectively. Calcification was present in 282 arteries from 89 patients, which was medial in 64%, intimal in 9%, and both in 27%. Bone was present in 6% of arteries, essentially all of which were heavily calcified. Multiple sampling revealed that the true prevalence of bone in heavily calcified arteries was 25%. Bone was more common in medial rather than intimal calcifications (10% vs 3%, p=0.03) but did not vary with artery location (above vs below the knee). Heavily calcified arteries with bone were more likely to come from patients who were older (p=0.04), had diabetes (p=0.06), or were receiving warfarin (p=0.06), but there was no association with gender or renal failure. Bone was almost always adjacent to calcifications, along the periphery, but never within. Staining for the bone-specific proteins osteocalcin and osterix was noted in 20% and 45% of heavily calcified arteries without visible bone. Osteoclasts were present in 4.9% of arteries, all of which were heavily calcified and most of which contained bone. The frequent absence of bone in heavily calcified vessels and the histologic pattern strongly suggests a secondary rather than primary event. Recruitment of osteoclasts to vascular calcifications can occur but is rare, suggesting a limited capacity to reverse calcifications.


Assuntos
Osso e Ossos/patologia , Extremidade Inferior/irrigação sanguínea , Osteoclastos/patologia , Doença Arterial Periférica/patologia , Calcificação Vascular/patologia , Idoso , Amputação Cirúrgica , Biomarcadores/análise , Osso e Ossos/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina/análise , Osteoclastos/química , Doença Arterial Periférica/etiologia , Doença Arterial Periférica/metabolismo , Doença Arterial Periférica/cirurgia , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fator de Transcrição Sp7 , Fatores de Transcrição/análise , Calcificação Vascular/etiologia , Calcificação Vascular/metabolismo , Calcificação Vascular/cirurgia
11.
Transplant Proc ; 56(6): 1247-1250, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38997886

RESUMO

INTRODUCTION: The widely employed Kidney Donor Profile Index (KDPI) scoring system, designed for assessing deceased donors (DD), plays a pivotal role in predicting graft function post kidney transplantation (KT). Given the dynamic nature of renal function, including serum creatinine (sCr), in managing DDs, it remains uncertain optimal timing to use KDPI for assessing postoperative graft function. METHODS: In this retrospective review, we assessed 246 DDs who were managed within a donor management program from January 2010 to December 2021. We collected sCr values for KDPI scoring at admission, peak, and last measurements before KT. Recipient data included occurrence of slow graft function (SGF), delayed graft function (DGF), and glomerular filtration rate (GFR) at one-year post-transplantation (1 Y). Using Receiver Operating Characteristic (ROC) and Pearson correlation analyses, we explored correlations of KDPI score (admission, peak, last) with graft function (SGF, DGF, GFR 1 Y). RESULTS: The average age of DDs and recipients was 49.78 ± 13.37 and 52.54 ± 10.49 years, respectively, with mean KDPI values at admission, peak, and last measurements of 62.36 ± 25.44, 66.94 ± 24.73, and 63.75 ± 25.80. After transplantation, SGF was observed in 81 recipients (32.9%) and DGF in 32 (13.0%). For SGF, the Area Under the Curve (AUC) from ROC analysis were 0.684 (95% CI, 0.615-0.753; P < .001) at admission, 0.691 (0.623-0.759; P < .001) at peak, and 0.697 (0.630-0.765; P < .001) at the last measurement. In predicting DGF, the corresponding AUC values were 0.746 (0.661-0.831; P < .001) at admission, 0.724 (0.637-0.810; P < .001) at peak, and 0.721 (0.643-0.809; P < .001) at the last. Moreover, KDPI scores at all time points-admission, peak, and last-moderately correlated with GFR 1 Y (R = -0.426, -0.423, -0.417). CONCLUSION: KDPI measurements at all time points, particularly admission, would be more effective in predicting DGF in DDKT.


Assuntos
Creatinina , Função Retardada do Enxerto , Taxa de Filtração Glomerular , Transplante de Rim , Doadores de Tecidos , Humanos , Pessoa de Meia-Idade , Creatinina/sangue , Estudos Retrospectivos , Feminino , Masculino , Adulto , Função Retardada do Enxerto/sangue , Função Retardada do Enxerto/diagnóstico , Fatores de Tempo , Rim/fisiopatologia , Rim/fisiologia , Sobrevivência de Enxerto , Testes de Função Renal
12.
Nano Converg ; 10(1): 19, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37115353

RESUMO

Remote epitaxy, which was discovered and reported in 2017, has seen a surge of interest in recent years. Although the technology seemed to be difficult to reproduce by other labs at first, remote epitaxy has come a long way and many groups are able to consistently reproduce the results with a wide range of material systems including III-V, III-N, wide band-gap semiconductors, complex-oxides, and even elementary semiconductors such as Ge. As with any nascent technology, there are critical parameters which must be carefully studied and understood to allow wide-spread adoption of the new technology. For remote epitaxy, the critical parameters are the (1) quality of two-dimensional (2D) materials, (2) transfer or growth of 2D materials on the substrate, (3) epitaxial growth method and condition. In this review, we will give an in-depth overview of the different types of 2D materials used for remote epitaxy reported thus far, and the importance of the growth and transfer method used for the 2D materials. Then, we will introduce the various growth methods for remote epitaxy and highlight the important points in growth condition for each growth method that enables successful epitaxial growth on 2D-coated single-crystalline substrates. We hope this review will give a focused overview of the 2D-material and substrate interaction at the sample preparation stage for remote epitaxy and during growth, which have not been covered in any other review to date.

13.
Sci Rep ; 12(1): 4301, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277566

RESUMO

Intersubband (intraband) transitions allow absorption of photons in the infrared spectral regime, which is essential for IR-photodetector and optical communication applications. Among various technologies, nanodisks embedded in nanowires offer a unique opportunity to be utilized in intraband devices due to the ease of tuning the fundamental parameters such as strain distribution, band energy, and confinement of the active region. Here, we show the transverse electric polarized intraband absorption using InGaN/GaN nanodisks cladded by AlGaN. Fourier transform infrared reflection (FTIR) measurement confirms absorption of normal incident in-plane transverse electric polarized photons in the mid-IR regime (wavelength of ~ 15 µm) at room temperature. The momentum matrix of the nanodisk energy states indicates electron transition from the ground state s into the px or py orbital-like excited states. Furthermore, the absorption characteristics depending on the indium composition and nanowire diameter exhibits tunability of the intraband absorption spectra within the nanodisks. We believe nanodisks embedded nanowires is a promising technology for achieving tunable detection of photons in the IR spectrum.

14.
Nat Nanotechnol ; 17(10): 1054-1059, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36138198

RESUMO

Heterogeneous integration of single-crystal materials offers great opportunities for advanced device platforms and functional systems1. Although substantial efforts have been made to co-integrate active device layers by heteroepitaxy, the mismatch in lattice polarity and lattice constants has been limiting the quality of the grown materials2. Layer transfer methods as an alternative approach, on the other hand, suffer from the limited availability of transferrable materials and transfer-process-related obstacles3. Here, we introduce graphene nanopatterns as an advanced heterointegration platform that allows the creation of a broad spectrum of freestanding single-crystalline membranes with substantially reduced defects, ranging from non-polar materials to polar materials and from low-bandgap to high-bandgap semiconductors. Additionally, we unveil unique mechanisms to substantially reduce crystallographic defects such as misfit dislocations, threading dislocations and antiphase boundaries in lattice- and polarity-mismatched heteroepitaxial systems, owing to the flexibility and chemical inertness of graphene nanopatterns. More importantly, we develop a comprehensive mechanics theory to precisely guide cracks through the graphene layer, and demonstrate the successful exfoliation of any epitaxial overlayers grown on the graphene nanopatterns. Thus, this approach has the potential to revolutionize the heterogeneous integration of dissimilar materials by widening the choice of materials and offering flexibility in designing heterointegrated systems.

15.
Science ; 377(6608): 859-864, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35981034

RESUMO

Recent advances in flexible and stretchable electronics have led to a surge of electronic skin (e-skin)-based health monitoring platforms. Conventional wireless e-skins rely on rigid integrated circuit chips that compromise the overall flexibility and consume considerable power. Chip-less wireless e-skins based on inductor-capacitor resonators are limited to mechanical sensors with low sensitivities. We report a chip-less wireless e-skin based on surface acoustic wave sensors made of freestanding ultrathin single-crystalline piezoelectric gallium nitride membranes. Surface acoustic wave-based e-skin offers highly sensitive, low-power, and long-term sensing of strain, ultraviolet light, and ion concentrations in sweat. We demonstrate weeklong monitoring of pulse. These results present routes to inexpensive and versatile low-power, high-sensitivity platforms for wireless health monitoring devices.


Assuntos
Monitorização Fisiológica , Tecnologia de Sensoriamento Remoto , Dispositivos Eletrônicos Vestíveis , Humanos , Monitorização Fisiológica/instrumentação , Pulso Arterial , Tecnologia de Sensoriamento Remoto/instrumentação , Semicondutores , Suor/química
16.
Transplant Proc ; 53(2): 565-568, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33549349

RESUMO

PURPOSE: Hemodynamic management in brain-dead donors (BDDs) is challenging due to hemodynamic instabilities. We compared functional parameters with traditional parameters for hemodynamic monitoring in BDDs. MATERIALS AND METHODS: Seventeen BDDs with a positive balance of >500 mL for 8 hours were included. Functional hemodynamic monitoring, including pulse pressure variation (PPV), stroke volume variation (SVV), cardiac output, and systemic vascular resistance index (SVRI) was performed in the setting of tidal volume of 6 mL/kg to 8 mL/kg and minimal positive end-expiratory pressure of 5 cm to 8 cm H2O. Responders were defined by a cardiac output increase of >15% after fluid therapy. RESULTS: Among the 17 BDDs (mean age, 46.80±13.91 years), 15 were male. Seven responders out of 17 (41.1%) had a significantly higher PPV (22.8±8.4 vs 13.4±5.9%, P = .038) and serum albumin level (3.2±0.6 vs 2.6±0.5 g/L, P = .040) at baseline than nonresponders. However, other hemodynamic markers such as SVV and SVRI were similar between groups. Traditional markers of volume status, such as heart rate, central venous pressure, hemoglobin, and serum uric acid level were also similar between the 2 groups. Hemodynamic markers including PPV, SVV, and SVRI were significantly reduced in responders. CONCLUSIONS: PPV was the most valuable hemodynamic marker for predicting volume responsiveness in BDDs.


Assuntos
Pressão Sanguínea/fisiologia , Morte Encefálica/diagnóstico , Hidratação/métodos , Adulto , Biomarcadores/análise , Morte Encefálica/fisiopatologia , Débito Cardíaco/fisiologia , Pressão Venosa Central , Feminino , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Respiração com Pressão Positiva , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Albumina Sérica/metabolismo , Volume Sistólico/fisiologia , Volume de Ventilação Pulmonar/fisiologia , Ácido Úrico/sangue , Resistência Vascular/fisiologia
17.
Sci Adv ; 7(27)2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34193431

RESUMO

Electronic skins (e-skins)-electronic sensors mechanically compliant to human skin-have long been developed as an ideal electronic platform for noninvasive human health monitoring. For reliable physical health monitoring, the interface between the e-skin and human skin must be conformal and intact consistently. However, conventional e-skins cannot perfectly permeate sweat in normal day-to-day activities, resulting in degradation of the intimate interface over time and impeding stable physical sensing. Here, we present a sweat pore-inspired perforated e-skin that can effectively suppress sweat accumulation and allow inorganic sensors to obtain physical health information without malfunctioning. The auxetic dumbbell through-hole patterns in perforated e-skins lead to synergistic effects on physical properties including mechanical reliability, conformability, areal mass density, and adhesion to the skin. The perforated e-skin allows one to laminate onto the skin with consistent homeostasis, enabling multiple inorganic sensors on the skin to reliably monitor the wearer's health over a period of weeks.

18.
ACS Nano ; 15(6): 10587-10596, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34081854

RESUMO

Remote epitaxy has drawn attention as it offers epitaxy of functional materials that can be released from the substrates with atomic precision, thus enabling production and heterointegration of flexible, transferrable, and stackable freestanding single-crystalline membranes. In addition, the remote interaction of atoms and adatoms through two-dimensional (2D) materials in remote epitaxy allows investigation and utilization of electrical/chemical/physical coupling of bulk (3D) materials via 2D materials (3D-2D-3D coupling). Here, we unveil the respective roles and impacts of the substrate material, graphene, substrate-graphene interface, and epitaxial material for electrostatic coupling of these materials, which governs cohesive ordering and can lead to single-crystal epitaxy in the overlying film. We show that simply coating a graphene layer on wafers does not guarantee successful implementation of remote epitaxy, since atomically precise control of the graphene-coated interface is required, and provides key considerations for maximizing the remote electrostatic interaction between the substrate and adatoms. This was enabled by exploring various material systems and processing conditions, and we demonstrate that the rules of remote epitaxy vary significantly depending on the ionicity of material systems as well as the graphene-substrate interface and the epitaxy environment. The general rule of thumb discovered here enables expanding 3D material libraries that can be stacked in freestanding form.

19.
PLoS One ; 16(6): e0252186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34097687

RESUMO

Renamezin® is a modified capsule-type oral spherical adsorptive carbon which lowers indoxyl sulfate levels in patients with advanced chronic kidney disease (CKD). This 24-week prospective observational cohort study was performed to evaluate the effect of Renamezin® upon attenuation of renal function decline. A total of 1,149 adult patients with baseline serum creatinine 2.0-5.0 mg/dL were enrolled from 22 tertiary hospital in Korea from April 2016 to September 2018. Among them, a total of 686 patients completed the study and were included in the intention-to-treat analysis. A total of 1,061 patients were included in the safety analysis. The mean age was 63.5 years and male patients were predominant (63.6%). Most of the patients (76.8%) demonstrated high compliance with study drug (6g per day). After 24 week of treatment, serum creatinine was increased from 2.86±0.72 mg/dL to 3.06±1.15 mg/dL (p<0.001), but estimated glomerular filtration rate was not changed significantly during observation period (22.3±6.8 mL/min/1.73m2 to 22.1±9.1 mL/min/1.73m2, p = 0.243). Patients with age over 65 years old and those under good systolic blood pressure control <130 mmHg were most likely to get benefit from Renamezin® treatment to preserve renal function. A total of 98 (9.2%) patients out of 1,061 safety population experienced 134 adverse events, of which gastrointestinal disorders were the most common. There were no serious treatment-related adverse events. Renamezin® can be used safely to attenuate renal function decline in moderately advanced CKD patients.


Assuntos
Carbono/administração & dosagem , Rim/diagnóstico por imagem , Insuficiência Renal Crônica/tratamento farmacológico , Creatinina/sangue , Diálise/métodos , Progressão da Doença , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Diálise Renal/métodos , Insuficiência Renal Crônica/sangue , República da Coreia , Fatores de Risco
20.
Kidney Int ; 78(2): 170-81, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20375985

RESUMO

Visfatin (also known as pre-B cell colony-enhancing factor) is a newly discovered adipocytokine that is preferentially produced by visceral fat and regulated by cytokines promoting insulin resistance. Here we determined its renal synthesis and physiology in a genetic model of type 2 diabetes in rats. These rats had higher levels of visfatin synthesis in both glomeruli and tubulointerstitium compared to control rats. Plasma visfatin levels were significantly increased in the early stages of diabetic nephropathy and positively correlated with body weight, fasting plasma glucose, and microalbuminuria. Interestingly, visfatin synthesis was found to occur in podocytes and proximal tubular cells, as well as in adipocytes in vitro. Further, in both renal cells, visfatin synthesis was significantly increased by high glucose in the media but not by angiotensin II. Additionally, visfatin treatment induced rapid uptake of glucose and was associated with increased translocation of GLUT-1 to the cellular membrane of both renal cell types. Furthermore, visfatin induced tyrosine phosphorylation of the insulin receptor, activated downstream insulin signaling pathways such as Erk-1, Akt, and p38 MAPK, and markedly increased the levels of TGFbeta1, PAI-1, type I collagen, and MCP-1 in both renal cells. Thus, our results suggest that visfatin is produced by renal cells and has an important paracrine role in the pathogenesis of diabetic nephropathy.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Rim/citologia , Nicotinamida Fosforribosiltransferase/fisiologia , Regulação para Cima , Animais , Citocinas/biossíntese , Glucose/metabolismo , Ratos , Ratos Endogâmicos OLETF , Ratos Long-Evans
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