Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 68
Filtrar
1.
Autophagy ; : 1-11, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695174

RESUMO

Defective mitophagy is consistently found in postmortem brain and iPSC-derived neurons from Alzheimer disease (AD) patients. However, there is a lack of extensive examination of mitophagy status in serum or cerebrospinal fluid (CSF), and the clinical potential of mitophagy biomarkers has not been tested. We quantified biomarkers of mitophagy/autophagy and lysosomal degradation (PINK1, BNIP3L and TFEB) in CSF and serum from 246 individuals, covering mild cognitive impairment due to AD (MCI-AD, n = 100), dementia due to AD (AD-dementia, n = 100), and cognitively unimpaired individuals (CU, n = 46), recruited from the Czech Brain Aging Study. Cognitive function and brain atrophy were also assessed. Our data show that serum and CSF PINK1 and serum BNIP3L were higher, and serum TFEB was lower in individuals with AD than in corresponding CU individuals. Additionally, the magnitude of mitophagy impairment correlated with the severity of clinical indicators in AD patients. Specifically, levels of PINK1 positively correlated with phosphorylated (p)-MAPT/tau (181), total (t)-MAPT/tau, NEFL (neurofilament light chain), and NRGN (neurogranin) levels in CSF and negatively with memory, executive function, and language domain. Serum TFEB levels negatively correlated with NEFL and positively with executive function and language. This study reveals mitophagy impairment reflected in biofluid biomarkers of individuals with AD and associated with more advanced AD pathology.Abbreviation: Aß: amyloid beta; AD: Alzheimer disease; AVs: autophagic vacuoles; BNIP3L: BCL2 interacting protein 3 like; CU: cognitively unimpaired; CSF: cerebrospinal fluid; LAMP1: lysosomal-associated membrane protein 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MCI: mild cognitive impairment; NRGN: neurogranin; NEFL: neurofilament light chain; p-MAPT/tau: phosphorylated microtubule associated protein tau; PINK1: PTEN induced kinase 1; t-MAPT/tau: total microtubule associated protein tau; TFEB: transcription factor EB; TMT: Trail Making Test.

2.
Science ; 383(6687): 1096-1103, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38452063

RESUMO

Monitoring homeostasis is an essential aspect of obtaining pathophysiological insights for treating patients. Accurate, timely assessments of homeostatic dysregulation in deep tissues typically require expensive imaging techniques or invasive biopsies. We introduce a bioresorbable shape-adaptive materials structure that enables real-time monitoring of deep-tissue homeostasis using conventional ultrasound instruments. Collections of small bioresorbable metal disks distributed within thin, pH-responsive hydrogels, deployed by surgical implantation or syringe injection, allow ultrasound-based measurements of spatiotemporal changes in pH for early assessments of anastomotic leaks after gastrointestinal surgeries, and their bioresorption after a recovery period eliminates the need for surgical extraction. Demonstrations in small and large animal models illustrate capabilities in monitoring leakage from the small intestine, the stomach, and the pancreas.


Assuntos
Implantes Absorvíveis , Fístula Anastomótica , Trato Gastrointestinal , Ultrassom , Animais , Humanos , Homeostase , Estômago , Trato Gastrointestinal/cirurgia , Fístula Anastomótica/diagnóstico por imagem , Modelos Animais
4.
Artigo em Inglês | MEDLINE | ID: mdl-38289789

RESUMO

Unhealthy aging poses a global challenge with profound healthcare and socioeconomic implications. Slowing down the aging process offers a promising approach to reduce the burden of a number of age-related diseases, such as dementia, and promoting healthy longevity in the old population. In response to the challenge of the aging population and with a view to the future, Norway and the United Kingdom are fostering collaborations, supported by a "Money Follows Cooperation agreement" between the 2 nations. The inaugural Norway-UK joint meeting on aging and dementia gathered leading experts on aging and dementia from the 2 nations to share their latest discoveries in related fields. Since aging is an international challenge, and to foster collaborations, we also invited leading scholars from 11 additional countries to join this event. This report provides a summary of the conference, highlighting recent progress on molecular aging mechanisms, genetic risk factors, DNA damage and repair, mitophagy, autophagy, as well as progress on a series of clinical trials (eg, using NAD+ precursors). The meeting facilitated dialogue among policymakers, administrative leaders, researchers, and clinical experts, aiming to promote international research collaborations and to translate findings into clinical applications and interventions to advance healthy aging.


Assuntos
Envelhecimento , Demência , Humanos , Idoso , Longevidade , Demência/prevenção & controle , Demência/epidemiologia , Reino Unido , Noruega
5.
Bioeng Transl Med ; 8(5): e10567, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37693063

RESUMO

Low-flow removal of refractory ascites is critical to treating cirrhosis and digestive system tumor, and thus, commercial ascites pump emerged lately. The rigid structure of clinically available pumps rises complication rate and lack of flow rate monitoring hinders early warning of abnormalities. Herein, a soft artificial system was proposed inspired by lymph for interactive ascites transfer with great biocompatibility. The implantable system is composed of pump cavity, valves and tubes, which are soft and flexible made by silica gel. Therefore, the system possesses similar modulus to tissues and can naturally fit surrounding tissues. The cavity with magnetic tablet embedded is driven by extracorporeal magnetic field. Subsequently, the system can drain ascites with a top speed of 23 mL min-1, much higher than that of natural lymphatic system and state-of-art devices. Moreover, integrated flexible sensors enable wireless, real-time flow rate monitoring, serving as proof of treatment adjustment, detection and locating of malfunction at early stage. The liver function of experimental objects was improved, and no severe complications occurred for 4 weeks, which proved its safety and benefit to treatment. This artificial lymphatic system can serve as a bridge to recovery and pave the way for further clinical research.

6.
Science ; 381(6662): 1105-1112, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37676965

RESUMO

Early-stage organ transplant rejection can be difficult to detect. Percutaneous biopsies occur infrequently and are risky, and measuring biomarker levels in blood can lead to false-negative and -positive outcomes. We developed an implantable bioelectronic system capable of continuous, real-time, long-term monitoring of the local temperature and thermal conductivity of a kidney for detecting inflammatory processes associated with graft rejection, as demonstrated in rat models. The system detects ultradian rhythms, disruption of the circadian cycle, and/or a rise in kidney temperature. These provide warning signs of acute kidney transplant rejection that precede changes in blood serum creatinine/urea nitrogen by 2 to 3 weeks and approximately 3 days for cases of discontinued and absent administration of immunosuppressive therapy, respectively.


Assuntos
Diagnóstico Precoce , Rejeição de Enxerto , Nefropatias , Transplante de Rim , Complicações Pós-Operatórias , Tecnologia sem Fio , Animais , Ratos , Rim , Rejeição de Enxerto/diagnóstico , Tecnologia sem Fio/instrumentação , Monitorização Fisiológica/instrumentação
7.
Sci Adv ; 9(30): eadi0357, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37494444

RESUMO

Three-dimensional (3D) curvy electronics has wide-ranging application in biomedical health care, soft machine, and high-density curved imager. Limited by material properties, complex procedures, and coverage ability of existing fabrication techniques, the development of high-performance 3D curvy electronics remains challenging. Here, we propose an automated wrap-like transfer printing prototype for fabricating 3D curvy electronics. Assisted by a gentle and uniform pressure field, the prefabricated planar circuits on the petal-like stamp are integrated onto the target surface intactly with full coverage. The driving pressure for the wrapping is provided by the strain recovery of a prestrained elastic film triggered by the air pressure control. The wrapping configuration and strain distribution of the stamp are simulated by finite element analysis, and the pattern and thickness of the stamps are optimized. Demonstration of this strategy including spherical meander antenna, spherical light-emitting diode array, and spherical solar cell array illustrates its feasibility in the development of complex 3D curvy electronics.

8.
Nat Commun ; 14(1): 4213, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37452047

RESUMO

Brain-computer interfaces (BCIs) have attracted considerable attention in motor and language rehabilitation. Most devices use cap-based non-invasive, headband-based commercial products or microneedle-based invasive approaches, which are constrained for inconvenience, limited applications, inflammation risks and even irreversible damage to soft tissues. Here, we propose in-ear visual and auditory BCIs based on in-ear bioelectronics, named as SpiralE, which can adaptively expand and spiral along the auditory meatus under electrothermal actuation to ensure conformal contact. Participants achieve offline accuracies of 95% in 9-target steady state visual evoked potential (SSVEP) BCI classification and type target phrases successfully in a calibration-free 40-target online SSVEP speller experiment. Interestingly, in-ear SSVEPs exhibit significant 2nd harmonic tendencies, indicating that in-ear sensing may be complementary for studying harmonic spatial distributions in SSVEP studies. Moreover, natural speech auditory classification accuracy can reach 84% in cocktail party experiments. The SpiralE provides innovative concepts for designing 3D flexible bioelectronics and assists the development of biomedical engineering and neural monitoring.


Assuntos
Interfaces Cérebro-Computador , Humanos , Potenciais Evocados Visuais , Eletroencefalografia , Calibragem , Idioma , Estimulação Luminosa , Algoritmos
9.
STAR Protoc ; 4(2): 102250, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37104093

RESUMO

Here, we present an olfactory-dependent chemotaxis assay for evaluating changes in memory-like behavior in both wild-type and Alzheimer's-disease-like C. elegans models. We describe steps for synchronizing and preparing C. elegans populations and for performing isoamyl alcohol conditioning during starvation and chemotaxis assaying. We then detail counting and quantification procedures. This protocol is applicable to mechanistic exploration and drug screening in neurodegenerative diseases and brain aging.

10.
Nat Biomed Eng ; 7(10): 1215-1228, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37037964

RESUMO

Devices for monitoring blood haemodynamics can guide the perioperative management of patients with cardiovascular disease. Current technologies for this purpose are constrained by wired connections to external electronics, and wireless alternatives are restricted to monitoring of either blood pressure or blood flow. Here we report the design aspects and performance parameters of an integrated wireless sensor capable of implantation in the heart or in a blood vessel for simultaneous measurements of pressure, flow rate and temperature in real time. The sensor is controlled via long-range communication through a subcutaneously implanted and wirelessly powered Bluetooth Low Energy system-on-a-chip. The device can be delivered via a minimally invasive transcatheter procedure or it can be mounted on a passive medical device such as a stent, as we show for the case of the pulmonary artery in a pig model and the aorta and left ventricle in a sheep model, where the device performs comparably to clinical tools for monitoring of blood flow and pressure. Battery-less and wireless devices such as these that integrate capabilities for flow, pressure and temperature sensing offer the potential for continuous monitoring of blood haemodynamics in patients.

11.
PeerJ ; 11: e14752, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36815979

RESUMO

Sirtuins (SIRTs 1-7) are a group of histone deacetylase enzymes with a wide range of enzyme activities that target a range of cellular proteins in the nucleus, cytoplasm, and mitochondria for posttranslational modifications by acetylation (SIRT1, 2, 3, and 5) or ADP ribosylation (SIRT4, 6, and 7). A variety of cellular functions, including mitochondrial functions and functions in energy homeostasis, metabolism, cancer, longevity and ageing, are regulated by sirtuins. Compromised sirtuin functions and/or alterations in the expression levels of sirtuins may lead to several pathological conditions and contribute significantly to alterations in metabolic phenotypes as well as oral carcinogenesis. Here, we describe the basic characteristics of seven mammalian sirtuins. This review also emphasizes the key molecular mechanisms of sirtuins in metabolic regulation and discusses the possible relationships of sirtuins with oral cancers. This review will provide novel insight into new therapeutic approaches targeting sirtuins that may potentially lead to effective strategies for combating oral malignancies.


Assuntos
Neoplasias Bucais , Sirtuínas , Animais , Sirtuínas/genética , Envelhecimento/genética , Longevidade , Carcinogênese , Mamíferos/metabolismo
12.
Connect Tissue Res ; 64(2): 105-116, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36271658

RESUMO

PURPOSE: As the population ages, there is an increased risk of fracture and morbidity diseases associated with aging, such as age-related osteoporosis and other bone diseases linked to aging skeletons. RESULTS: Several bone-related cells, including multipotent bone mesenchymal stem cells, osteoblasts that form bone tissue, and osteoclasts that break it down, are in symbiotic relationships throughout life. Growing evidence indicates that epigenetic modifications of cells caused by aging contribute to compromised bone remodeling and lead to osteoporosis. A number of epigenetic mechanisms are at play, including DNA/RNA modifications, histone modifications, microRNAs (miRNAs), and long noncoding RNAs (lncRNAs), as well as chromatin remodeling. CONCLUSION: In this review, we summarized the epigenetic modifications of different bone-related cells during the development and progression of osteoporosis associated with aging. Additionally, we described a compensatory recovery mechanism under epigenetic regulation that may lead to new strategies for regulating bone remodeling in age-related osteoporosis.


Assuntos
Doenças Ósseas , MicroRNAs , Osteoporose , Humanos , Epigênese Genética , Osteoporose/genética , MicroRNAs/genética , Doenças Ósseas/genética , Remodelação Óssea/genética
13.
Adv Healthc Mater ; 12(4): e2202021, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36337006

RESUMO

Accurate measurements of skin hydration are of great interest to dermatological science and clinical practice. This parameter serves as a relevant surrogate of skin barrier function, a key representative benchmark for overall skin health. The skin hydration sensor (SHS) is a soft, skin-interfaced wireless system that exploits a thermal measurement method, as an alternative to conventional impedance-based hand-held probes. This study presents multiple strategies for maximizing the sensitivity and reliability of this previously reported SHS platform. An in-depth analysis of the thermal physics of the measurement process serves as the basis for structural optimizations of the electronics and the interface to the skin. Additional engineering advances eliminate variabilities associated with manual use of the device and with protocols for the measurement. The cumulative effect is an improvement in sensitivity by 135% and in repeatability by 36% over previously reported results. Pilot trials on more than 200 patients in a dermatology clinic validate the practical utility of the sensor for fast, reliable measurements.


Assuntos
Dispositivos Eletrônicos Vestíveis , Humanos , Reprodutibilidade dos Testes , Pele/química , Eletrônica/métodos , Tecnologia sem Fio
14.
Nat Commun ; 13(1): 6518, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36316354

RESUMO

Physically transient forms of electronics enable unique classes of technologies, ranging from biomedical implants that disappear through processes of bioresorption after serving a clinical need to internet-of-things devices that harmlessly dissolve into the environment following a relevant period of use. Here, we develop a sustainable manufacturing pathway, based on ultrafast pulsed laser ablation, that can support high-volume, cost-effective manipulation of a diverse collection of organic and inorganic materials, each designed to degrade by hydrolysis or enzymatic activity, into patterned, multi-layered architectures with high resolution and accurate overlay registration. The technology can operate in patterning, thinning and/or cutting modes with (ultra)thin eco/bioresorbable materials of different types of semiconductors, dielectrics, and conductors on flexible substrates. Component-level demonstrations span passive and active devices, including diodes and field-effect transistors. Patterning these devices into interconnected layouts yields functional systems, as illustrated in examples that range from wireless implants as monitors of neural and cardiac activity, to thermal probes of microvascular flow, and multi-electrode arrays for biopotential sensing. These advances create important processing options for eco/bioresorbable materials and associated electronic systems, with immediate applicability across nearly all types of bioelectronic studies.


Assuntos
Implantes Absorvíveis , Eletrônica , Semicondutores , Eletrodos , Lasers
15.
Nature ; 609(7928): 701-708, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36131035

RESUMO

Dynamic shape-morphing soft materials systems are ubiquitous in living organisms; they are also of rapidly increasing relevance to emerging technologies in soft machines1-3, flexible electronics4,5 and smart medicines6. Soft matter equipped with responsive components can switch between designed shapes or structures, but cannot support the types of dynamic morphing capabilities needed to reproduce natural, continuous processes of interest for many applications7-24. Challenges lie in the development of schemes to reprogram target shapes after fabrication, especially when complexities associated with the operating physics and disturbances from the environment can stop the use of deterministic theoretical models to guide inverse design and control strategies25-30. Here we present a mechanical metasurface constructed from a matrix of filamentary metal traces, driven by reprogrammable, distributed Lorentz forces that follow from the passage of electrical currents in the presence of a static magnetic field. The resulting system demonstrates complex, dynamic morphing capabilities with response times within 0.1 second. Implementing an in situ stereo-imaging feedback strategy with a digitally controlled actuation scheme guided by an optimization algorithm yields surfaces that can follow a self-evolving inverse design to morph into a wide range of three-dimensional target shapes with high precision, including an ability to morph against extrinsic or intrinsic perturbations. These concepts support a data-driven approach to the design of dynamic soft matter, with many unique characteristics.

16.
Nat Commun ; 13(1): 5576, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36151092

RESUMO

Low modulus materials that can shape-morph into different three-dimensional (3D) configurations in response to external stimuli have wide-ranging applications in flexible/stretchable electronics, surgical instruments, soft machines and soft robotics. This paper reports a shape-programmable system that exploits liquid metal microfluidic networks embedded in an elastomer matrix, with electromagnetic forms of actuation, to achieve a unique set of properties. Specifically, this materials structure is capable of fast, continuous morphing into a diverse set of continuous, complex 3D surfaces starting from a two-dimensional (2D) planar configuration, with fully reversible operation. Computational, multi-physics modeling methods and advanced 3D imaging techniques enable rapid, real-time transformations between target shapes. The liquid-solid phase transition of the liquid metal allows for shape fixation and reprogramming on demand. An unusual vibration insensitive, dynamic 3D display screen serves as an application example of this type of morphable surface.

17.
Int J Biometeorol ; 66(3): 481-491, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35064318

RESUMO

Understanding environmental determination of crop yield plays a critical role in agricultural. management in resource-limited areas. The climatic transition zone was a naturally ideal place to study. the relations between environmental factors and crop yield, due to its large annual variability of climatic factors and high speed of temperature increase under global warming. Our objectives were to identify the most critical environmental factor in determining spring wheat yield and analyze the convergence and divergence of water-yield relations for spring wheat in a typical climatic transition zone (semi-arid area). The study was conducted at two locations, Dingxi and Pengyang in Northwest China, with a long-term experiment (1987-2018) and two short-term irrigation experiments. Meanwhile, data of water use and spring wheat yield was collected from a series of previously published literature in the study area. The highest spring wheat yield was obtained under year pattern with higher soil water content at sowing (SWCS) and lower atmospheric dryness condition (ADC, the difference between reference evapotranspiration and precipitation during spring wheat growing season). SWCS was more important than precipitation during the growing season (PGS) in determining spring wheat yield in the study area. The relations between available water supply, water use, and spring wheat yield were convergence. However, SWCS had an impact on the relationship between yield and PGS and SWCS-yield relation was affected by ADC. We concluded that precipitation in 7 months before sowing was the dominant factor determining spring wheat yield in the climatic transition zone under global warming whereas the impact of high atmospheric evaporative demand resulted from the increasing temperature on crop yields and SWCS-yield relation must be taken into account for the analysis of environmental determination of spring wheat yield.


Assuntos
Aquecimento Global , Triticum , Agricultura , China , Clima , Estações do Ano , Água
18.
Nat Biomed Eng ; 6(1): 76-93, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34992270

RESUMO

A reduced removal of dysfunctional mitochondria is common to aging and age-related neurodegenerative pathologies such as Alzheimer's disease (AD). Strategies for treating such impaired mitophagy would benefit from the identification of mitophagy modulators. Here we report the combined use of unsupervised machine learning (involving vector representations of molecular structures, pharmacophore fingerprinting and conformer fingerprinting) and a cross-species approach for the screening and experimental validation of new mitophagy-inducing compounds. From a library of naturally occurring compounds, the workflow allowed us to identify 18 small molecules, and among them two potent mitophagy inducers (Kaempferol and Rhapontigenin). In nematode and rodent models of AD, we show that both mitophagy inducers increased the survival and functionality of glutamatergic and cholinergic neurons, abrogated amyloid-ß and tau pathologies, and improved the animals' memory. Our findings suggest the existence of a conserved mechanism of memory loss across the AD models, this mechanism being mediated by defective mitophagy. The computational-experimental screening and validation workflow might help uncover potent mitophagy modulators that stimulate neuronal health and brain homeostasis.


Assuntos
Doença de Alzheimer , Mitofagia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides , Animais , Aprendizado de Máquina , Mitofagia/fisiologia , Fluxo de Trabalho
19.
Sci Adv ; 7(43): eabj3686, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34669471

RESUMO

Microfluidic technologies have wide-ranging applications in chemical analysis systems, drug delivery platforms, and artificial vascular networks. This latter area is particularly relevant to 3D cell cultures, engineered tissues, and artificial organs, where volumetric capabilities in fluid distribution are essential. Existing schemes for fabricating 3D microfluidic structures are constrained in realizing desired layout designs, producing physiologically relevant microvascular structures, and/or integrating active electronic/optoelectronic/microelectromechanical components for sensing and actuation. This paper presents a guided assembly approach that bypasses these limitations to yield complex 3D microvascular structures from 2D precursors that exploit the full sophistication of 2D fabrication methods. The capabilities extend to feature sizes <5 µm, in extended arrays and with various embedded sensors and actuators, across wide ranges of overall dimensions, in a parallel, high-throughput process. Examples include 3D microvascular networks with sophisticated layouts, deterministically designed and constructed to expand the geometries and operating features of artificial vascular networks.

20.
Sci Rep ; 11(1): 20258, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642363

RESUMO

Direct-current generators, especially those based on the Schottky contacts between conductive polymers and metal electrodes, are efficient in converting mechanical stimuli into electrical energy. In contrast to triboelectric and piezoelectric generators, direct-current generators readily produce direct-current outputs and high currents that are crucial for integrating multiple energy-harvesting units in large scale and driving some types of devices. We are focusing on the relationship between Schottky barrier height and performance, systematically investigating the effects of various conductive polymers and electrodes on the outputs by both theoretical simulation and experiments. Tailoring the Schottky barrier height between conductive polymers and metal electrodes is demonstrated a significant approach to design the new DC generators. The preparation method of electrochemical deposition endows the generators flexibility, the linear relationship of current/voltage output vs. strain applied on the generators, combined with the large outputs offer advantages for the generator to work as flexible sensors. Furthermore, a mechanosensation-active matrix array based on direct-current generator for the strain monitoring demonstrated its promising prospects in flexible electronics. The direct-current generators with improved performance could serve as a stream new blood for versatile sensory systems and human-machine interactive interfaces.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...