Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 121(22): e2404007121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38768347

RESUMO

Sensations of heat and touch produced by receptors in the skin are of essential importance for perceptions of the physical environment, with a particularly powerful role in interpersonal interactions. Advances in technologies for replicating these sensations in a programmable manner have the potential not only to enhance virtual/augmented reality environments but they also hold promise in medical applications for individuals with amputations or impaired sensory function. Engineering challenges are in achieving interfaces with precise spatial resolution, power-efficient operation, wide dynamic range, and fast temporal responses in both thermal and in physical modulation, with forms that can extend over large regions of the body. This paper introduces a wireless, skin-compatible interface for thermo-haptic modulation designed to address some of these challenges, with the ability to deliver programmable patterns of enhanced vibrational displacement and high-speed thermal stimulation. Experimental and computational investigations quantify the thermal and mechanical efficiency of a vertically stacked design layout in the thermo-haptic stimulators that also supports real-time, closed-loop control mechanisms. The platform is effective in conveying thermal and physical information through the skin, as demonstrated in the control of robotic prosthetics and in interactions with pressure/temperature-sensitive touch displays.


Assuntos
Tato , Realidade Virtual , Tecnologia sem Fio , Humanos , Tecnologia sem Fio/instrumentação , Tato/fisiologia , Pele , Robótica/instrumentação , Robótica/métodos
2.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33468630

RESUMO

Precise, quantitative measurements of the hydration status of skin can yield important insights into dermatological health and skin structure and function, with additional relevance to essential processes of thermoregulation and other features of basic physiology. Existing tools for determining skin water content exploit surrogate electrical assessments performed with bulky, rigid, and expensive instruments that are difficult to use in a repeatable manner. Recent alternatives exploit thermal measurements using soft wireless devices that adhere gently and noninvasively to the surface of the skin, but with limited operating range (∼1 cm) and high sensitivity to subtle environmental fluctuations. This paper introduces a set of ideas and technologies that overcome these drawbacks to enable high-speed, robust, long-range automated measurements of thermal transport properties via a miniaturized, multisensor module controlled by a long-range (∼10 m) Bluetooth Low Energy system on a chip, with a graphical user interface to standard smartphones. Soft contact to the surface of the skin, with almost zero user burden, yields recordings that can be quantitatively connected to hydration levels of both the epidermis and dermis, using computational modeling techniques, with high levels of repeatability and insensitivity to ambient fluctuations in temperature. Systematic studies of polymers in layered configurations similar to those of human skin, of porcine skin with known levels of hydration, and of human subjects with benchmarks against clinical devices validate the measurement approach and associated sensor hardware. The results support capabilities in characterizing skin barrier function, assessing severity of skin diseases, and evaluating cosmetic and medication efficacy, for use in the clinic or in the home.


Assuntos
Eletrônica , Pele/patologia , Água , Tecnologia sem Fio , Adolescente , Adulto , Pré-Escolar , Análise de Elementos Finitos , Humanos , Temperatura
3.
Proc Natl Acad Sci U S A ; 118(19)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33893178

RESUMO

Capabilities in continuous monitoring of key physiological parameters of disease have never been more important than in the context of the global COVID-19 pandemic. Soft, skin-mounted electronics that incorporate high-bandwidth, miniaturized motion sensors enable digital, wireless measurements of mechanoacoustic (MA) signatures of both core vital signs (heart rate, respiratory rate, and temperature) and underexplored biomarkers (coughing count) with high fidelity and immunity to ambient noises. This paper summarizes an effort that integrates such MA sensors with a cloud data infrastructure and a set of analytics approaches based on digital filtering and convolutional neural networks for monitoring of COVID-19 infections in sick and healthy individuals in the hospital and the home. Unique features are in quantitative measurements of coughing and other vocal events, as indicators of both disease and infectiousness. Systematic imaging studies demonstrate correlations between the time and intensity of coughing, speaking, and laughing and the total droplet production, as an approximate indicator of the probability for disease spread. The sensors, deployed on COVID-19 patients along with healthy controls in both inpatient and home settings, record coughing frequency and intensity continuously, along with a collection of other biometrics. The results indicate a decaying trend of coughing frequency and intensity through the course of disease recovery, but with wide variations across patient populations. The methodology creates opportunities to study patterns in biometrics across individuals and among different demographic groups.


Assuntos
COVID-19/fisiopatologia , Frequência Cardíaca , Taxa Respiratória , Sons Respiratórios , SARS-CoV-2 , Tecnologia sem Fio , Biomarcadores , Humanos , Monitorização Fisiológica
4.
Phytother Res ; 2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39099170

RESUMO

Sarcopenia is a condition marked by a significant reduction in muscle mass and strength, primarily due to the aging process, which critically impacts muscle protein dynamics, metabolic functions, and overall physical functionality. This condition leads to increased body fat and reduced daily activity, contributing to severe health issues and a lower quality of life among the elderly. Recognized in the ICD-10-CM only in 2016, sarcopenia lacks definitive treatment options despite its growing prevalence and substantial social and economic implications. Given the aging global population, addressing sarcopenia has become increasingly relevant and necessary. The primary causes include aging, cachexia, diabetes, and nutritional deficiencies, leading to imbalances in protein synthesis and degradation, mitochondrial dysfunction, and hormonal changes. Exercise remains the most effective intervention, but it is often impractical for individuals with limited mobility, and pharmacological options such as anabolic steroids and myostatin inhibitors are not FDA-approved and are still under investigation. This review is crucial as it examines the potential of natural products as a novel treatment strategy for sarcopenia, targeting multiple mechanisms involved in its pathogenesis. By exploring natural products' multi-targeted effects, this study aims to provide innovative and practical solutions for sarcopenia management. Therefore, this review indicates significant improvements in muscle mass and function with the use of specific natural compounds, suggesting promising alternatives for those unable to engage in regular physical activity.

5.
Int J Mol Sci ; 25(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38256144

RESUMO

As the global population ages, the prevalence of Parkinson's disease (PD) is steadily on the rise. PD demonstrates chronic and progressive characteristics, and many cases can transition into dementia. This increases societal and economic burdens, emphasizing the need to find effective treatments. Among the widely recognized causes of PD is the abnormal accumulation of proteins, and autophagy dysfunction accelerates this accumulation. The resultant Lewy bodies are also commonly found in Alzheimer's disease patients, suggesting an increased potential for the onset of dementia. Additionally, the production of free radicals due to mitochondrial dysfunction contributes to neuronal damage and degeneration. The activation of astrocytes and the M1 phenotype of microglia promote damage to dopamine neurons. The drugs currently used for PD only delay the clinical progression and exacerbation of the disease without targeting its root cause, and come with various side effects. Thus, there is a demand for treatments with fewer side effects, with much potential offered by natural products. In this study, we reviewed a total of 14 articles related to herbal medicines and natural products and investigated their relevance to possible PD treatment. The results showed that the reviewed herbal medicines and natural products are effective against lysosomal disorder, mitochondrial dysfunction, and inflammation, key mechanisms underlying PD. Therefore, natural products and herbal medicines can reduce neurotoxicity and might improve both motor and non-motor symptoms associated with PD. Furthermore, these products, with their multi-target effects, enhance bioavailability, inhibit antibiotic resistance, and might additionally eliminate side effects, making them good alternative therapies for PD treatment.


Assuntos
Doença de Alzheimer , Produtos Biológicos , Doenças Mitocondriais , Doença de Parkinson , Plantas Medicinais , Humanos , Doença de Parkinson/tratamento farmacológico , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Extratos Vegetais
6.
Int J Mol Sci ; 24(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37240173

RESUMO

Alzheimer's disease and Parkinson's disease are the two most common neurodegenerative diseases in the world, and their incidence rates are increasing as our society ages. This creates a significant social and economic burden. Although the exact cause and treatment methods for these diseases are not yet known, research suggests that Alzheimer's disease is caused by amyloid precursor protein, while α-synuclein acts as a causative agent in Parkinson's disease. The accumulation of abnormal proteins such as these can lead to symptoms such as loss of protein homeostasis, mitochondrial dysfunction, and neuroinflammation, which ultimately result in the death of nerve cells and the progression of neurodegenerative diseases. The medications currently available for these diseases only delay their progression and have many adverse effects, which has led to increased interest in developing natural products with fewer adverse effects. In this study, we selected specific keywords and thesis content to investigate natural products that are effective in treating Alzheimer's and Parkinson's diseases. We reviewed 16 papers on natural products and found that they showed promising mechanisms of action such as antioxidant, anti-inflammatory, and mitochondrial function improvement. Other natural products with similar properties could also be considered potential treatments for neurodegenerative diseases, and they can be consumed as part of a healthy diet rather than as medicine.


Assuntos
Doença de Alzheimer , Produtos Biológicos , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Precursor de Proteína beta-Amiloide
7.
Int J Mol Sci ; 22(3)2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525754

RESUMO

Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common neurodegenerative diseases. Many studies have demonstrated that the release of NLRP3 inflammasome-mediated proinflammatory cytokines by the excessive activation of microglia is associated with the pathogenesis of AD and PD and suggested that the NLRP3 inflammasome plays an important role in AD and PD development. In both diseases, various stimuli, such as Aß and α-synuclein, accelerate the formation of the NLRP3 inflammasome in microglia and induce pyroptosis through the expression of interleukin (IL)-1ß, caspase-1, etc., where neuroinflammation contributes to gradual progression and deterioration. However, despite intensive research, the exact function and regulation of the NLRP3 inflammasome has not yet been clearly identified. Moreover, there have not yet been any experiments of clinical use, although many studies have recently been conducted to improve treatment of inflammatory diseases using various inhibitors for NLRP3 inflammasome pathways. However, recent studies have reported that various natural products show improvement effects in the in vivo models of AD and PD through the regulation of NLRP3 inflammasome assembly. Therefore, the present review provides an overview of natural extraction studies aimed at the prevention or treatment of NLRP3 inflammasome-mediated neurological disorders. It is suggested that the discovery and development of these various natural products could be a potential strategy for NLRP3 inflammasome-mediated AD and PD treatment.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Inflamassomos/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Produtos Biológicos/farmacologia , Citocinas/metabolismo , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doença de Parkinson/metabolismo , Transdução de Sinais/efeitos dos fármacos
8.
Nat Mater ; 22(2): 155-156, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36477675

Assuntos
Semicondutores , Pele
9.
Health Qual Life Outcomes ; 16(1): 213, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30453961

RESUMO

BACKGROUND: Facial palsy is known to have correlations with low level of quality of life. However, little is known about the association between preference based health-related quality of life (HRQoL) and paralytic side of facial palsy. METHODS: This study used Korea National Health and Nutrition Examination Survey (KNHANES, 2008-2012) data, only when the facial palsy examination had been included in the survey contents. Hierarchical regression analyses were used to obtain optimal regression coefficients in the association between paralytic side of the facial palsy and HRQoL measured by EuroQoL-5 Dimension (EQ-5D). We also analyzed the association between the deteriorated domains of EQ-5D and facial palsy in both subgroups by using multiple logistic regression models. RESULTS: We included the data of 28,106 participants aged ≥19 years who were examined as facial palsy according to House-Brackmann score and completed EQ-5D questionnaire in KNHANES 2008-2012. The mean EQ-5D score was significantly low and percentages of deteriorated numbers in its domains were significantly high in facial palsy group. CONCLUSIONS: These results show that, after adjusting for confounding variables, left facial palsy is associated with impaired HRQoL compared with right-sided palsy. Among the domains of EQ-5D, only 'self-care' domain was directly affected by the disease in left facial palsy patients. These findings could be used in developing model and conducting analyses of economic evaluation about facial palsy interventions.


Assuntos
Paralisia Facial/psicologia , Qualidade de Vida , Adulto , Idoso , Estudos Transversais , Paralisia Facial/classificação , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Inquéritos Nutricionais , República da Coreia , Autocuidado , Adulto Jovem
10.
Sensors (Basel) ; 18(1)2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29351218

RESUMO

In this paper, we introduce a transparent fingerprint sensing system using a thin film transistor (TFT) sensor panel, based on a self-capacitive sensing scheme. An armorphousindium gallium zinc oxide (a-IGZO) TFT sensor array and associated custom Read-Out IC (ROIC) are implemented for the system. The sensor panel has a 200 × 200 pixel array and each pixel size is as small as 50 µm × 50 µm. The ROIC uses only eight analog front-end (AFE) amplifier stages along with a successive approximation analog-to-digital converter (SAR ADC). To get the fingerprint image data from the sensor array, the ROIC senses a capacitance, which is formed by a cover glass material between a human finger and an electrode of each pixel of the sensor array. Three methods are reviewed for estimating the self-capacitance. The measurement result demonstrates that the transparent fingerprint sensor system has an ability to differentiate a human finger's ridges and valleys through the fingerprint sensor array.

11.
Appl Environ Microbiol ; 83(11)2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28341680

RESUMO

Five genes encoding PhaP family proteins and one phaR gene have been identified in the genome of Burkholderia symbiont strain RPE75. PhaP proteins function as the surface proteins of polyhydroxyalkanoate (PHA) granules, and the PhaR protein acts as a negative regulator of PhaP biosynthesis. Recently, we characterized one phaP gene to understand the molecular cross talk between Riptortus insects and Burkholderia gut symbionts. In this study, we constructed four other phaP gene-depleted mutants (ΔphaP1, ΔphaP2, ΔphaP3, and ΔphaP4 mutants), one phaR gene-depleted mutant, and a phaR-complemented mutant (ΔphaR/phaR mutant). To address the biological roles of four phaP family genes and the phaR gene during insect-gut symbiont interaction, these Burkholderia mutants were fed to the second-instar nymphs, and colonization ability and fitness parameters were examined. In vitro, the ΔphaP3 and ΔphaR mutants cannot make a PHA granule normally in a stressful environment. Furthermore, the ΔphaR mutation decreased the colonization ability in the host midgut and negatively affected the host insect's fitness compared with wild-type Burkholderia-infected insects. However, other phaP family gene-depleted mutants colonized well in the midgut of the fifth-instar nymph insects. However, in the case of females, the colonization rate of the ΔphaP3 mutant was decreased and the host's fitness parameters were decreased compared with the wild-type-infected host, suggesting that the environment of the female midgut may be more hostile than that of the male midgut. These results demonstrate that PhaR plays an important role in the biosynthesis of PHA granules and that it is significantly related to the colonization of the Burkholderia gut symbiont in the host insects' midgut.IMPORTANCE Bacterial polyhydroxyalkanoate (PHA) biosynthesis is a complex process requiring several enzymes. The biological roles of PHA granule synthesis enzymes and the surface proteins of PHA granules during host-gut symbiont interactions are not fully understood. Here, we report the effects on colonization ability in the host midguts and the fitness of host insects after feeding Burkholderia mutant cells (four phaP-depleted mutants and one phaR-depleted mutant) to the host insects. Analyses of both synthesized PHA granule amounts and CFU numbers suggest that the phaR gene is closely related to synthesis of the PHA granule and the colonization of the Burkholderia gut symbiont in the host insect's midgut. Like our previous report, this study also supports the idea that the environment of the host midgut may not be favorable to symbiotic Burkholderia cells and that PHA granules may be required to adapt in the host midgut.


Assuntos
Proteínas de Bactérias/metabolismo , Burkholderia/crescimento & desenvolvimento , Burkholderia/metabolismo , Regulação Bacteriana da Expressão Gênica , Heterópteros/microbiologia , Simbiose , Animais , Proteínas de Bactérias/genética , Burkholderia/genética , Burkholderia/isolamento & purificação , Sistema Digestório/microbiologia , Feminino , Heterópteros/fisiologia , Masculino
12.
Angew Chem Int Ed Engl ; 56(6): 1571-1575, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28035781

RESUMO

The development of efficient metal-free organic emitters with thermally activated delayed fluorescence (TADF) properties for deep-blue emission is still challenging. A new family of deep-blue TADF emitters based on a donor-acceptor architecture has been developed. The electronic interaction between donor and acceptor plays a key role in the TADF mechanism. Deep-blue OLEDs fabricated with these TADF emitters achieved high external quantum efficiencies over 19.2 % with CIE coordinates of (0.148, 0.098).

13.
Angew Chem Int Ed Engl ; 56(52): 16536-16540, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29105906

RESUMO

A family of organic emitters with a donor-σ-acceptor (D-σ-A) motif is presented. Owing to the weakly coupled D-σ-A intramolecular charge-transfer state, a transition from the localized excited triplet state (3 LE) and charge-transfer triplet state (3 CT) to the charge-transfer singlet state (1 CT) occurred with a small activation energy and high photoluminescence quantum efficiency. Two thermally activated delayed fluorescence (TADF) components were identified, one of which has a very short lifetime of 200-400 ns and the other a longer TADF lifetime of the order of microseconds. In particular, the two D-σ-A materials presented strong blue emission with TADF properties in toluene. These results will shed light on the molecular design of new TADF emitters with short delayed lifetimes.

14.
Angew Chem Int Ed Engl ; 55(24): 6864-8, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27101424

RESUMO

Much effort has been devoted to developing highly efficient organic light-emitting diodes (OLEDs) that function through phosphorescence or thermally activated delayed fluorescence (TADF). However, efficient host materials for blue TADF and phosphorescent guest emitters are limited because of their requirement of high triplet energy levels. Herein, we report the rigid acceptor unit benzimidazobenzothiazole (BID-BT), which is suitable for use in bipolar hosts in blue OLEDs. The designed host materials, based on BID-BT, possess high triplet energy and bipolar carrier transport ability. Both blue TADF and phosphorescent OLEDs containing BID-BT-based derivatives exhibit external quantum efficiencies as high as 20 %, indicating that these hosts allow efficient triplet exciton confinement appropriate for blue TADF and phosphorescent guest emitters.

15.
Nanotechnology ; 26(41): 415301, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26391964

RESUMO

Gecko-like dry adhesive using high aspect ratio polymeric nanohairs has insuperable limitations, although it has huge potential in many applications. Repeated harsh contacts on a target substrate lead to physical collapse of nanohairs and significant degradation of the adhesion property, because the polymeric nanohairs are quite fragile due to poor mechanical robustness. Herein, we demonstrate a highly robust gecko-like dry adhesive with unidirectionally stooped polymeric nanohairs (diameter 100 nm) with a high aspect ratio (∼9) using an ultrathin metal coating. 100 cycles of repeated adhesion tests with 1 N preloading force did not significantly degrade adhesion or cause collapse of nanohairs. We believe that this approach allows gecko-like dry adhesive to be utilized in many related applications and diverse industry interests.

16.
Ann Dermatol ; 36(1): 29-34, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38325431

RESUMO

BACKGROUND: Analysis of hair microscopic morphology is a simple and less invasive method to differentiate alopecia areata (AA) from other alopecic diseases. However, there is limited information on the distribution of the microscopic characteristics. OBJECTIVE: This study evaluated the microscopic morphological characteristics of pulled-out hair and their correlation with disease course in AA. METHODS: Morphological characteristics of pulled-out hair were classified into 5 categories: the presence of typical clubbing, surface undulation, tapering, breakage, and depigmentation in proximal hair shaft. Clinical course of AA was investigated through assessment of Severity of Alopecia Tool (SALT) score (initial score, maximal score and difference of them [ΔSALT]). RESULTS: Among 1,272 pulled-out hairs (n=179) obtained at initial visit, depigmentation (59.5%) was the most common, followed by loss of typical clubbing (57.2%) and surface undulation (55.2%). The percentage of loss of typical clubbing and proximal tapering was significantly higher in severe type of AA, younger age of onset and shorter disease duration. The ratio of typical clubbing (<50% vs. ≥50%) was associated with difference in maximal score and ΔSALT (p<0.05). Strong activity group (pulled-out hair ≥10, n=33) showed difference in clinical course (maximal score, ΔSALT) as well as distribution of microscopic features (loss of typical clubbing) compared with those in non-strong activity group. The ratio of typical clubbing significantly increased at follow-up than initially in strong activity group (p<0.05). CONCLUSION: Microscopic hair morphology, especially loss of typical clubbing and proximal tapering, could be useful tool to predict the course of AA.

17.
J Pharmacopuncture ; 27(1): 53-57, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38560337

RESUMO

The purpose of this study is to report the clinical application of Hominis Placenta Pharmacopunture for Alopecia areata. Patient was diagnosed as stress-induced Alopecia areata 1 years ago. To reduce symptom, we treated a patient 8 times using Hominis Placenta Pharmacopunture. Hominis Placenta was injected subcutaneously into the lesion of head scalp alopecia. According to photographs, the lesion had been replaced with new terminal hair and the size of the lesion had decreased. This case has shown that stress-induced Alopecia areata patient could be treated by Hominis Placenta Pharmacopunture.

18.
Adv Mater ; : e2406783, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39388528

RESUMO

Native oxides form on the surface of many metals. Here, using gallium-based liquid metal alloys, Johnson-Kendall-Roberts (JKR) measurements are employed to show that native oxide dramatically lower the tension of the metal interface from 724 to 10 mN m-1. Like conventional surfactants, the oxide has asymmetry between the composition of its internal and external interfaces. Yet, in comparison to conventional surfactants, oxides are an order of magnitude more effective at lowering tension and do not need to be added externally to the liquid (i.e., oxides form naturally on metals). This surfactant-like asymmetry explains the adhesion of oxide-coated metals to surfaces. The resulting low interfacial energy between the metal and the interior of the oxide helps stabilize non-spherical liquid metal structures. In addition, at small enough macroscopic contact angles, the finite tension of the liquid within the oxide can drive fluid instabilities that are useful for separating the oxide from the metal to form oxide-encased bubbles or deposit thin oxide films (1-5 nm) on surfaces. Since oxides form on many metals, this work can have implications for a wide range of metals and metal oxides in addition to explaining the physical behavior of liquid metal.

19.
Nat Commun ; 15(1): 10, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38169465

RESUMO

Tactile function is essential for human life as it enables us to recognize texture and respond to external stimuli, including potential threats with sharp objects that may result in punctures or lacerations. Severe skin damage caused by severe burns, skin cancer, chemical accidents, and industrial accidents damage the structure of the skin tissue as well as the nerve system, resulting in permanent tactile sensory dysfunction, which significantly impacts an individual's daily life. Here, we introduce a fully-implantable wireless powered tactile sensory system embedded artificial skin (WTSA), with stable operation, to restore permanently damaged tactile function and promote wound healing for regenerating severely damaged skin. The fabricated WTSA facilitates (i) replacement of severely damaged tactile sensory with broad biocompatibility, (ii) promoting of skin wound healing and regeneration through collagen and fibrin-based artificial skin (CFAS), and (iii) minimization of foreign body reaction via hydrogel coating on neural interface electrodes. Furthermore, the WTSA shows a stable operation as a sensory system as evidenced by the quantitative analysis of leg movement angle and electromyogram (EMG) signals in response to varying intensities of applied pressures.


Assuntos
Pele Artificial , Humanos , Biônica , Tato/fisiologia , Pele , Cicatrização , Órgãos dos Sentidos
20.
Front Microbiol ; 14: 1278917, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029092

RESUMO

The reason why the potent entomopathogen Serratia marcescens fails to kill insects through oral infection is unknown. To compare effects of septic injection and oral administration of S. marcescens, we used a model bean bug, Riptortus pedestris. Most R. pedestris insects survived oral infections, but not septic infections. Although the number of S. marcescens cells in hemolymph after oral infection, which were originated from gut-colonizing S. marcescens, was higher than the fatal number of cells used in septic injection, they did not kill host insects, suggesting a loss of virulence in gut-colonizing S. marcescens cells. When gut-colonizing S. marcescens cells were septically injected into insects, they failed to kill R. pedestris and survive in hemolymph. To understand the avirulence mechanisms in gut-colonizing bacteria, lipopolysaccharides of S. marcescens were analyzed and revealed that the O antigen was lost during gut colonization. Gut-colonizing S. marcescens cells were resistant to humoral immune responses but susceptible to cellular immune responses, easily succumbing to phagocytosis of hemocytes. When cellular immunity was suppressed, the gut-colonizing S. marcescens cells recovered their virulence and killed insects through septic injection. These results suggest that a key mechanism of avirulence in orally infected S. marcescens is the loss of the O antigen, resulting in susceptibility to host's cellular immune responses.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA