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1.
Artigo em Inglês | MEDLINE | ID: mdl-34360379

RESUMO

Although the use of audio feedback with devices such as metronomes during cardiopulmonary resuscitation (CPR) is a simple method for improving CPR quality, its effect on the quality of pediatric CPR has not been adequately evaluated. In this study, 64 healthcare providers performed CPR (with one- and two-handed chest compression (OHCC and THCC, respectively)) on a pediatric resuscitation manikin (Resusci Junior QCPR), with and without audio feedback using a metronome (110 beats/min). CPR was performed on the floor, with a compression-to-ventilation ratio of 30:2. For both OHCC and THCC, the rate of achievement of an adequate compression rate during CPR was significantly higher when performed with metronome feedback than that without metronome feedback (CPR with vs. without feedback: 100.0% (99.0, 100.0) vs. 94.0% (69.0, 99.0), p < 0.001, for OHCC, and 100.0% (98.5, 100.0) vs. 91.0% (34.5, 98.5), p < 0.001, for THCC). However, the rate of achievement of adequate compression depth during the CPR performed was significantly higher without metronome feedback than that with metronome feedback (CPR with vs. without feedback: 95.0% (23.5, 99.5) vs. 98.5% (77.5, 100.0), p = 0.004, for OHCC, and 99.0% (95.5, 100.0) vs. 100.0% (99.0, 100.0), p = 0.003, for THCC). Although metronome feedback during pediatric CPR could increase the rate of achievement of adequate compression rates, it could cause decreased compression depth.


Assuntos
Reanimação Cardiopulmonar , Criança , Retroalimentação , Retroalimentação Sensorial , Humanos , Manequins , Pressão
2.
Nat Commun ; 12(1): 4731, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354053

RESUMO

Electrodermal devices that capture the physiological response of skin are crucial for monitoring vital signals, but they often require convoluted layered designs with either electronic or ionic active materials relying on complicated synthesis procedures, encapsulation, and packaging techniques. Here, we report that the ionic transport in living systems can provide a simple mode of iontronic sensing and bypass the need of artificial ionic materials. A simple skin-electrode mechanosensing structure (SEMS) is constructed, exhibiting high pressure-resolution and spatial-resolution, being capable of feeling touch and detecting weak physiological signals such as fingertip pulse under different skin humidity. Our mechanical analysis reveals the critical role of instability in high-aspect-ratio microstructures on sensing. We further demonstrate pressure mapping with millimeter-spatial-resolution using a fully textile SEMS-based glove. The simplicity and reliability of SEMS hold great promise of diverse healthcare applications, such as pulse detection and recovering the sensory capability in patients with tactile dysfunction.


Assuntos
Fenômenos Fisiológicos da Pele , Tato/fisiologia , Dispositivos Eletrônicos Vestíveis , Fenômenos Biomecânicos , Simulação por Computador , Eletrodos , Desenho de Equipamento , Dedos/fisiologia , Análise de Elementos Finitos , Humanos , Mecanorreceptores/fisiologia , Pressão , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído , Têxteis , Dispositivos Eletrônicos Vestíveis/estatística & dados numéricos
3.
Nature ; 596(7871): 238-243, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34381233

RESUMO

Structured fabrics, such as woven sheets or chain mail armours, derive their properties both from the constitutive materials and their geometry1,2. Their design can target desirable characteristics, such as high impact resistance, thermal regulation, or electrical conductivity3-5. Once realized, however, the fabrics' properties are usually fixed. Here we demonstrate structured fabrics with tunable bending modulus, consisting of three-dimensional particles arranged into layered chain mails. The chain mails conform to complex shapes2, but when pressure is exerted at their boundaries, the particles interlock and the chain mails jam. We show that, with small external pressure (about 93 kilopascals), the sheets become more than 25 times stiffer than in their relaxed configuration. This dramatic increase in bending resistance arises because the interlocking particles have high tensile resistance, unlike what is found for loose granular media. We use discrete-element simulations to relate the chain mail's micro-structure to macroscale properties and to interpret experimental measurements. We find that chain mails, consisting of different non-convex granular particles, undergo a jamming phase transition that is described by a characteristic power-law function akin to the behaviour of conventional convex media. Our work provides routes towards lightweight, tunable and adaptive fabrics, with potential applications in wearable exoskeletons, haptic architectures and reconfigurable medical supports.


Assuntos
Fenômenos Mecânicos , Têxteis , Exoesqueleto Energizado , Humanos , Maleabilidade , Pressão , Resistência à Tração , Dispositivos Eletrônicos Vestíveis
4.
Appl Ergon ; 97: 103548, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34391990

RESUMO

Measurement of pressure threshold has found its applications in the fields of medical sciences and product design. Hence it has been a profound area of research interest for several decades. However, hardly any detailed investigation has been undertaken to measure the pressure threshold in the head region. In this study, Pressure Discomfort Threshold (PDT) and Pressure Pain Threshold (PPT) were measured for two hundred eighteen healthy Chinese adults at seventy-six anatomical locations, and further statistical analyses were performed on the acquired data to understand the relationship between different demographic parameters. The results suggest that the pressure sensitivity is low in the vertex region, moderate in the forehead and temporal area, and high in the facial and nasal region. From this study, pressure sensitivity maps were developed for PDT and PPT for Chinese adults. The measured pressure threshold data showed no significant relationship with age and Body Mass Index (BMI).


Assuntos
Limiar da Dor , Projetos de Pesquisa , Adulto , China , Humanos , Medição da Dor , Pressão
5.
Medicine (Baltimore) ; 100(31): e26511, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34397794

RESUMO

ABSTRACT: Pain sensitization leading to polyalgia can be observed during infectious diseases. The blood pressure cuff-evoked pain threshold (BPCEPT) has been used in previous studies as a screening tool for fibromyalgia.We aimed to use the BPCEPT as a screening test for detecting pain sensitization in patients suffering from infectious diseases. We also investigated whether specific factors were associated with pain sensitization.We performed a prospective comparative study including all patients of our infectious diseases center in a 1-year period. We created a positive control group of patients suffering from fibromyalgia and a negative control group of "apparently healthy" patients consulting for vaccination.The blood pressure (BP) cuff was inflated until the patient signaled that they experienced pain, and this pressure value was noted.A total of 2355 patients were included. The positive control group had significantly lower values of the BPCEPT than all other groups. Among hospitalized patients with infectious diseases, a low BPCEPT was significantly associated with high temperature (P < .0001), older age (P = .002), being a woman (P = .004), high serum glutamic-oxaloacetic transaminase (P = .007), and high C reactive protein levels (P = .02). Moreover, in multivariate analysis, respiratory infection, meningitis, urinary tract infection, febrile neutropenia, and Q fever were independently associated with a low BPCEPT. A significant negative dynamic correlation between the BPCEPT and temperature was also observed (P < .001).We demonstrated for the first time in a large sample of patients that the BPCEPT method can be used to detect pain susceptibility. We observed a significant dynamic correlation between pain sensitization and temperature. Additionally, pain sensitization was associated with some diseases, suggesting that they trigger pain sensitivity.


Assuntos
Determinação da Pressão Arterial , Temperatura Corporal , Infecções/complicações , Dor/etiologia , Fatores Etários , Aspartato Aminotransferases/sangue , Determinação da Pressão Arterial/efeitos adversos , Proteína C-Reativa/metabolismo , Suscetibilidade a Doenças/diagnóstico , Suscetibilidade a Doenças/microbiologia , Suscetibilidade a Doenças/fisiopatologia , Feminino , Fibromialgia/complicações , Humanos , Infecções/fisiopatologia , Masculino , Pessoa de Meia-Idade , Dor/fisiopatologia , Limiar da Dor , Pressão/efeitos adversos , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais
6.
Nutrients ; 13(7)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34371947

RESUMO

Nutritional status is well-known to influence patient recovery after resection of head and neck cancer (HNC). The influence of preoperative nutritional status on dysphagia was assessed in patients who underwent surgical resection of HNC along with the assessment of nutritional status during the acute and subacute phases. Eighty-six patients underwent surgical resection and dysphagia assessments (repetitive saliva-swallowing test, water-swallowing test, and functional oral intake scale) and had their tongue pressure assessed five times (before surgery, after 1-2 weeks, and 1, 2, and 3 months after surgery). The nutritional status was assessed according to the body mass index, total protein, and albumin. The prognostic nutritional index was calculated from preoperative data, and the subjects were classified into three groups: Low-risk, Attention and High-risk groups. After surgery, the nutritional status index values were low, and the High-risk group showed significantly lower values in comparison to the other two groups. The water-swallowing test and functional oral intake scale findings were worse than they had been preoperatively until 2 months after surgery, and a significant correlation was noted between the postoperative nutritional status and the presence of dysphagia. The results indicated that the preoperative nutritional status of HNC patients influenced their ability to ingest/swallow, which in turn influenced their nutritional status after HNC resection.


Assuntos
Transtornos de Deglutição/etiologia , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/cirurgia , Estado Nutricional , Idoso , Deglutição , Ingestão de Alimentos , Feminino , Neoplasias de Cabeça e Pescoço/fisiopatologia , Humanos , Masculino , Avaliação Nutricional , Complicações Pós-Operatórias , Período Pós-Operatório , Período Pré-Operatório , Pressão , Estudos Prospectivos , Língua
7.
Molecules ; 26(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34443533

RESUMO

Quercetin is a polyphenolic compound, the effects of which raise scientists' doubts. The results of many experiments show that it has anticancer, antiinflammatory, and antioxidant properties, while other studies indicate its pro-oxidative and cytotoxic action. This compound can react with reactive oxygen species, and due to its chemical properties, it can be found in the hydrophobic-hydrophilic area of cells. These features of quercetin indicate that its action in cells will be associated with the modification of membranes and its participation in maintaining the redox balance. Therefore, this study distinguishes these two mechanisms and determines whether they are important for cell function. We check: (1) Whether the selected concentrations of quercetin are cytotoxic and destructive for SK-N-SH cell membranes (MTT, LDH, MDA tests) in situations with and without the applied oxidative stress; (2) what is the level of changes in the structural/mechanical properties of the lipid part of the membranes of these cells due to the presence of polyphenol molecules; and (3) whether the antioxidative action of quercetin protects the membrane against its modification. Our results show that changes in the stiffness/elasticity of the lipid part of the membrane constitute the decisive mechanism of action of quercetin, potentially influencing cellular processes whose initial stages are associated with membranes (e.g., reception of signals from the environment, transport).


Assuntos
Membrana Celular/efeitos dos fármacos , Neuroblastoma/patologia , Quercetina/farmacologia , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , L-Lactato Desidrogenase/metabolismo , Ozônio/farmacologia , Pressão , Temperatura
8.
Molecules ; 26(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34443535

RESUMO

Pressure is one of the most important parameters controlling the kinetics of chemical reactions. The ability to combine high-pressure techniques with time-resolved spectroscopy has provided a powerful tool in the study of reaction mechanisms. This review is focused on the supporting role of high-pressure kinetic and spectroscopic methods in the exploration of nitric oxide bioinorganic chemistry. Nitric oxide and other reactive nitrogen species (RNS) are important biological mediators involved in both physiological and pathological processes. Understanding molecular mechanisms of their interactions with redox-active metal/non-metal centers in biological targets, such as cofactors, prosthetic groups, and proteins, is crucial for the improved therapy of various diseases. The present review is an attempt to demonstrate how the application of high-pressure kinetic and spectroscopic methods can add additional information, thus enabling the mechanistic interpretation of various NO bioinorganic reactions.


Assuntos
Química Bioinorgânica , Óxido Nítrico/química , Pressão , Hemeproteínas/análise , Cinética , Porfirinas/química
9.
Undersea Hyperb Med ; 48(3): 209-219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34390625

RESUMO

Eustachian tube dysfunction (ETD) and middle ear barotrauma (MEB) are common reported complications during hyperbaric oxygen treatment. Our Phase I study data was the first to demonstrate a statistically significant decrease in the occurrence of symptomatic ETD and MEB. The Phase I Trial suggested the total time interval and rate (slope) of compression (ROC) may be a determining factor in ETD and MEB. This Phase II study investigates an optimal rate of compression to reduce ETD and MEB when considering each multiplace treatment (with multiple patients) as the unit of observation as a group, rather than for each individual patient. Data were collected prospectively on 1,244 group patient-treatment exposures, collectively including 5,072 individual patient-treatment/exposures. We randomly assigned patient-treatment group exposures to four different time interval and rate (slope) of compression. These compression rates and slopes were identical to those used in the Phase I trial. All patients experiencing symptoms of MEB requiring compression stops were evaluated post treatment for the presence of ETD and MEB using the O'Neill Grading System (OGS) for ETD. Data were analyzed using the IBM-SPSS statistical software program. A statistically significant decrease in the number of compression holds was observed in the 15-minute compression schedule, correlating to the results observed in the Phase I trial. The 15-minute linear compression profile continues to demonstrate the decreased need for patient symptomatic compression stops (as in the Phase I trial) using a USN TT9 during elective hyperbaric oxygen treatments in a Class A multiplace hyperbaric chamber. Trial Registration: ClinicalTrials.gov Identifier: NCT04776967.


Assuntos
Barotrauma/epidemiologia , Otopatias/epidemiologia , Orelha Média/lesões , Tuba Auditiva/lesões , Oxigenação Hiperbárica/efeitos adversos , Barotrauma/etiologia , Barotrauma/prevenção & controle , Otopatias/etiologia , Otopatias/prevenção & controle , Orelha Média/fisiologia , Humanos , Oxigenação Hiperbárica/métodos , Oxigenação Hiperbárica/estatística & dados numéricos , Incidência , Pressão/efeitos adversos , Estudos Prospectivos , Análise de Regressão , Fatores de Tempo , Suspensão de Tratamento/estatística & dados numéricos
10.
Medicine (Baltimore) ; 100(32): e26938, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34397944

RESUMO

BACKGROUND: Glaucoma, is the most common cause of irreversible visual deficits, presents as an injury to the optic nerve and it is mainly associated with elevated intraocular pressure. The main symptom of glaucoma is a reduction of the visual field, which is usually a source of complaint at the advanced stage of disease. Because of visual deficit, gait dysfunctions, including low gait speed and increased bumping into objects, postural sway, and falling are occurred. Many studies have used stopwatch or motion-sensing devices to report on gait function following glaucoma. However, there are few reports on gait dysfunction assessed by examining foot pressure. This study investigated gait ability following glaucoma according to different gait conditions by assessing foot pressure. METHODS: Thirty older adults (15 in the sex- and age-matched normal group and 15 in the glaucoma group) were recruited for this study. All participants were walked under 2 different gait conditions in an F-scan system and the subject' assessments were randomly assigned to rule out the order effect. Conditions included: gait over an obstacle in a straight 6 m path, gait in a straight path without an obstacle in the 6 m path. Gait variables included cadence, gait cycle, stance time, center of force (COF) deviation, and COF excursion. About 10 minutes were taken for gait evaluation. RESULTS: When walking without an obstacle on a 6 m path, there were significant differences between the 2 groups in gait speed, cadence, gait cycle, and stance time (P < .05). There were significant differences when walking with an obstacle on a 6 m path (P < .05). Two-way analysis of variance showed significant effects associated with "glaucoma" not gait condition on all outcomes except for COF deviation and excursion. Also, there was no the interaction effect between "glaucoma" and "gait condition." CONCLUSION: We demonstrated that glaucoma patients selected the gait strategy such as lower gait function in both gait conditions particularly, slower gait speed and cadence and longer gait cycle and stance time, as determined by examining foot pressure. We believe that our results could help to improve the quality of life of patients with glaucoma.


Assuntos
Pé/fisiopatologia , Marcha/fisiologia , Glaucoma/fisiopatologia , Qualidade de Vida , Sapatos , Caminhada/fisiologia , Idoso , Fenômenos Biomecânicos , Estudos Transversais , Feminino , Humanos , Masculino , Equilíbrio Postural/fisiologia , Pressão , Velocidade de Caminhada/fisiologia
11.
Comput Biol Med ; 135: 104598, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34346320

RESUMO

Over the past decade, Finite Element (FE) modelling has been used as a method to understand the internal stresses within the diabetic foot. Foot deformities such as hammer toe have been associated with increased risk of foot ulcers in diabetic patients. Hence the aim of this study is to investigate the influence of hammer toe deformity on internal stresses during walking. A 3D finite element model of the human foot was constructed based on capturing Magnetic Resonance Imaging (MRI) of a diabetic neuropathic volunteer exhibiting hammer toe. 3D gait measurements and a multi-body musculoskeletal model for the same participant were used to define muscle forces. FE simulations were run at five different instances during the stance phase of gait. Peak plantar pressure and pressure distribution results calculated from the model showed a good agreement with the experimental measurement having less than 11% errors. Maximum von Mises internal stresses in the forefoot hard tissue were observed at the 3rd and 5th metatarsals and 4th proximal phalanx. Moreover, presence of hammer toe deformity was found to shift the location of maximum internal stresses on the soft tissue to the forefoot by changing the location of centre of pressure with internal stress 1.64 times greater than plantar pressure. Hammer toe deformity also showed to reduce the involvement of the first phalanx in internal/external load-bearing during walking. The findings of this study support the association between changes in loading pattern, deformity, and internal stresses in the soft tissue that lead to foot ulceration.


Assuntos
Pé Diabético , Síndrome do Dedo do Pé em Martelo , Fenômenos Biomecânicos , Pé Diabético/diagnóstico por imagem , Análise de Elementos Finitos , Síndrome do Dedo do Pé em Martelo/diagnóstico por imagem , Humanos , Pressão , Estresse Mecânico , Caminhada
12.
J Appl Clin Med Phys ; 22(9): 332-338, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34347931

RESUMO

OBJECTIVE: To compare conventional method and compressed-sensing (CS) accelerated 3D balanced fast field echo imaging (bFFE) of inner ear. METHODS: Twenty patients with suspected inner ear disease underwent CS accelerated 3D-bFFE (CS-bFFE) and conventional 3D-bFFE (Con-bFFE) by a 3T MRI. The overall image quality, motion artifacts, and image quality of specific structures of inner ear were assessed on ordinal scales by three radiologists who were blinded to the scan protocols. Kendall W test was used to evaluate interobserver agreement and Wilcoxon test was performed to compare the image quality and motion artifacts between CS-bFFE and Con-bFFE. RESULTS: The acquisition duration of CS-bFFE (1 min 53 s) was 49% faster than Con-bFFE. Three radiologists had good inter-observer agreement of image quality (Kendall W value of 0.829 for CS-bFFE and 0.815 for Con-bFFE) and motion artifacts evaluation (Kendall W value of 0861 for CS-bFFE and 0.707 for Con-bFFE). The better overall image quality of CS-bFFE was assessed (4.93 ± 0.23 for CS-bFFE, 4.53 ± 0.70 for Con-bFFE, Z = -2.254, p = 0.024). The image quality score of facial and cochlear nerve gained higher in CS-bFFE (4.93 ± 0.23 for CS-bFFE, 4.58 ± 0.64 for Con-bFFE, Z = -2.094, p = 0.036). No significant difference of motion artifacts (p = 0.050) between CS-bFFE and Con-bFFE. CONCLUSIONS: The CS-bFFE improves image quality and reduces acquisition time significantly, and it is a feasible MRI protocol for inner ear imaging.


Assuntos
Orelha Interna , Imageamento por Ressonância Magnética , Artefatos , Orelha Interna/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Pressão
13.
Exp Gerontol ; 153: 111505, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34343633

RESUMO

OBJECTIVES: To investigate age-related changes in the intramuscular adipose tissue (IAT) of the tongue and geniohyoid muscle (GHM) and associated factors. DESIGN: Exploratory cross-sectional study. SETTING AND PARTICIPANTS: This study included 89 participants recruited from a health survey, which included 38 younger adults (age range, 20-63 years) and 51 older adults (age range, 65-87 years). MEASUREMENTS: Age, body mass index, body fat, lean body mass, skeletal muscle mass index, trunk muscle mass index, tongue pressure, jaw opening force, and oral diadochokinesis were assessed. The cross-sectional area (CSA) and echo intensity (EI) of the tongue and GHM were measured using ultrasonography. IAT was assessed according to EI values. The factors related to the IAT of each muscle were examined using multiple regression analysis. We also investigated the correlation of IAT with factors related to oral function and systemic and morphological factors. RESULTS: Neither the EI of the tongue nor that of the GHM had a significant correlation with factors related to oral function and systemic factors. In the multiple regression analysis, significant explanatory variables for EI of the tongue and GHM were age (ß = 0.14, P = 0.019; tongue and ß = 0.13, P = 0.017; GHM) and the CSA of each muscle (ß = -0.01, P = 0.042; tongue and ß = -0.04, P = 0.003; GHM). EI was positively associated with age and negatively associated with muscle CSA. CONCLUSION: Age-related changes in the IAT show the same trend for both the tongue and GHM, unlike age-related changes in muscle mass. The IATs of the tongue and GHM were not significantly correlated with oral function and systemic factors. Therefore, EI may not be a useful index for the functional evaluation of the tongue and GHM.


Assuntos
Deglutição , Força Muscular , Tecido Adiposo/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Humanos , Músculo Esquelético , Pressão , Língua/diagnóstico por imagem
14.
J Oral Rehabil ; 48(10): 1173-1182, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34346106

RESUMO

BACKGROUND: Oral hypofunction is defined as the reversible stage preceding oral dysfunction. However, its assessment and management need further examination and consideration. OBJECTIVE: The present study aimed to examine the current state of oral hypofunction among outpatients at the university hospital. METHODS: New outpatients underwent medical interviews and detailed assessment of oral hypofunction at their initial visit to our dental department. Oral hypofunction was diagnosed if the results of three of the following seven assessment items were below cut-off values: poor oral hygiene, oral dryness, reduced occlusal force, decreased tongue-lip motor function, decreased tongue pressure, decreased masticatory function and deterioration of swallowing function. The relationships between factors used to diagnose oral hypofunction as well as the distributions of assessment values were clarified. RESULTS: Seventy-five of 209 patients (35.9%) were finally diagnosed with oral hypofunction. Diagnosis of oral hypofunction was significantly related to patient age, Eichner index, a chief complaint of dental or periodontal disease or ill-fitting dentures and a history of neurodegenerative disease. The lowest quintile values for poor oral hygiene, oral dryness and decreased masticatory performance were all above current cut-off values. Reduced occlusal force contributed strongly to the diagnosis of oral hypofunction. CONCLUSION: Oral hypofunction in dental outpatients at a university hospital was associated with patient age, medical history and chief complaint at presentation. Diagnosis of oral hypofunction can be closely related to reduced occlusal force. The validity of cut-off values for assessments of oral hypofunction needs further consideration.


Assuntos
Doenças Neurodegenerativas , Pacientes Ambulatoriais , Idoso , Estudos Transversais , Hospitais , Humanos , Pressão , Língua
15.
Nat Commun ; 12(1): 5008, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429436

RESUMO

Capabilities for continuous monitoring of pressures and temperatures at critical skin interfaces can help to guide care strategies that minimize the potential for pressure injuries in hospitalized patients or in individuals confined to the bed. This paper introduces a soft, skin-mountable class of sensor system for this purpose. The design includes a pressure-responsive element based on membrane deflection and a battery-free, wireless mode of operation capable of multi-site measurements at strategic locations across the body. Such devices yield continuous, simultaneous readings of pressure and temperature in a sequential readout scheme from a pair of primary antennas mounted under the bedding and connected to a wireless reader and a multiplexer located at the bedside. Experimental evaluation of the sensor and the complete system includes benchtop measurements and numerical simulations of the key features. Clinical trials involving two hemiplegic patients and a tetraplegic patient demonstrate the feasibility, functionality and long-term stability of this technology in operating hospital settings.


Assuntos
Técnicas Biossensoriais/métodos , Fontes de Energia Elétrica , Pressão , Temperatura , Tecnologia sem Fio , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Pele , Termografia/instrumentação , Termografia/métodos
16.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443607

RESUMO

Cellular conformation of reduced pyridine nucleotides NADH and NADPH sensed using autofluorescence spectroscopy is presented as a real-time metabolic indicator under pressurized conditions. The approach provides information on the role of pressure in energy metabolism and antioxidant defense with applications in agriculture and food technologies. Here, we use spectral phasor analysis on UV-excited autofluorescence from Saccharomyces cerevisiae (baker's yeast) to assess the involvement of one or multiple NADH- or NADPH-linked pathways based on the presence of two-component spectral behavior during a metabolic response. To demonstrate metabolic monitoring under pressure, we first present the autofluorescence response to cyanide (a respiratory inhibitor) at 32 MPa. Although ambient and high-pressure responses remain similar, pressure itself also induces a response that is consistent with a change in cellular redox state and ROS production. Next, as an example of an autofluorescence response altered by pressurization, we investigate the response to ethanol at ambient, 12 MPa, and 30 MPa pressure. Ethanol (another respiratory inhibitor) and cyanide induce similar responses at ambient pressure. The onset of non-two-component spectral behavior upon pressurization suggests a change in the mechanism of ethanol action. Overall, results point to new avenues of investigation in piezophysiology by providing a way of visualizing metabolism and mitochondrial function under pressurized conditions.


Assuntos
NADP/química , NADP/metabolismo , NAD/química , NAD/metabolismo , Pressão , Fluorescência , Conformação Molecular
17.
Medicine (Baltimore) ; 100(29): e26633, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34398020

RESUMO

BACKGROUND: Endotracheal tube (ETT) with a tapered-shaped cuff had an improved sealing effect when compared to ETTs with a conventional cylindrical-shaped cuff. Positional change and neck movement typically displace an ETT and change the intracuff pressure. The aim of the current study was to compare the ETT cuff pressure in the TaperGuard ETT vs the conventional ETT after a change from the supine, neutral position to the extension of the neck and semi-Fowler position for thyroid surgery. METHODS: This prospective, randomized clinical trial included 50 patients undergoing thyroidectomy. Patients were randomly allocated into one of the 2 groups: tracheal intubation with the TaperGuard ETT or with a conventional ETT. The ETT cuff was inflated with air and the ETT cuff pressure was set initially at 20 cmH2O using a calibrated cuff manometer. ETT cuff pressure and distance from carina to ETT tip were measured at supine and semi-Fowler positions with neck extension. RESULTS: After the position change, the ETT tip migrated cephalad and cuff pressure increased in the majority of cases. ETT cuff pressure was significantly higher in the TaperGuard group than the conventional group (28.0 ±â€Š6.6 cmH2O and 22.8 ±â€Š4.5 cmH2O, respectively, P = .001). The degree of cephalad displacement of the ETT tip was comparable between the 2 groups (19.4 ±â€Š6.31 mm in TaperGuard group and 21.9 ±â€Š6.9 mm in conventional group, P = .12). CONCLUSIONS: After the position change from supine to hyperextension of the neck, the ETT cuff pressure was higher in the TaperGuard ETT than in the conventional ETT, although the extent of displacement of the ETT was comparable between the 2 groups.


Assuntos
Intubação Intratraqueal/instrumentação , Tireoidectomia , Traqueia , Adolescente , Adulto , Idoso , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão , Estudos Prospectivos , Decúbito Dorsal , Resultado do Tratamento , Adulto Jovem
18.
Molecules ; 26(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208026

RESUMO

In this study, the impact of different cell disruption techniques (high-pressure micro fluidization (HPMF), ionic liquids (ILs), multi-enzyme (ME), and hydrochloric acid (HCl)) on the chemical composition and biological activity of astaxanthin (AST) obtained from Haematococcus pluvialis was investigated. Results indicated that all cell disruption techniques had a significant effect on AST composition, which were confirmed by TLC and UPC2 analysis. AST recovery from HCl (HCl-AST) and ILs (ILs-AST) cell disruption techniques was dominant by free and monoesters AST, while AST recovery from HPMF (HPMF-AST) and ME (ME-AST) cell disruption techniques was composed of monoesters, diesters, and free AST. Further biological activity analysis displayed that HCl-AST showed the highest ABTS and DPPH activity, while ILs-AST showed better results against the ORAC assay. Additionally, ILs-AST exhibits a stronger anti-proliferation of HepG2 cells in a dose-dependent manner, which was ascribed to AST-induced ROS in to inhibit the proliferative of cancer cells.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Clorofíceas/química , Extratos Vegetais/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Proliferação de Células , Células Hep G2 , Humanos , Líquidos Iônicos , Estrutura Molecular , Extratos Vegetais/farmacologia , Pressão , Xantofilas/isolamento & purificação , Xantofilas/farmacologia
19.
Sensors (Basel) ; 21(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34300635

RESUMO

This paper reports on a mask-type sensor for simultaneous pulse wave and respiration measurements and eye blink detection that uses only one sensing element. In the proposed sensor, a flexible air bag-shaped chamber whose inner pressure change can be measured by a microelectromechanical system-based piezoresistive cantilever was used as the sensing element. The air bag-shaped chamber is fabricated by wrapping a sponge pad with plastic film and polyimide tape. The polyimide tape has a hole to which the substrate with the piezoresistive cantilever adheres. By attaching the sensor device to a mask where it contacts the nose of the subject, the sensor can detect the pulses and eye blinks of the subject by detecting the vibration and displacement of the nose skin caused by these physiological parameters. Moreover, the respiration of the subject causes pressure changes in the space between the mask and the face of the subject as well as slight vibrations of the mask. Therefore, information about the respiration of the subject can be extracted from the sensor signal using either the low-frequency component (<1 Hz) or the high-frequency component (>100 Hz). This paper describes the sensor fabrication and provides demonstrations of the pulse wave and respiration measurements as well as eye blink detection using the fabricated sensor.


Assuntos
Sistemas Microeletromecânicos , Piscadela , Frequência Cardíaca , Pressão , Respiração
20.
ACS Sens ; 6(7): 2630-2641, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34228442

RESUMO

With the fast development of consumer electronic and artificial intelligence equipment, flexible pressure sensors (FPSs) have become a momentous component in the application of wearable electronic, electronic skin, and human-machine interfacing. The capacitive FPS possesses the merits of low energy consumption, high resolution, and fast dynamic response, so it is ideal for mobile and wearable electronics. However, capacitive FPS is vulnerable to electromagnetic interference and parasitic capacitance due to its low sensitivity. Microstructure or porous dielectric materials have been applied to improve the sensitivity of the capacitive FPS, but the high sensitivity is just limited to a narrow region. In this work, we propose a different strategy that incorporates a high-permittivity MXene nanocomposite dielectric with a 3D network electrode (3DNE) to improve the sensing performance of the capacitive FPS. Thanks to the high permittivity of the dielectric layer and hierarchical deformation of the electrode, the fabricated capacitive FPS exhibits a high sensitivity of 10.2 kPa-1 in the low pressure range (0-8.6 kPa) and still maintains a relatively high sensitivity of 3.65 kPa-1 with a near-linear response in a wide pressure range (8.6-100 kPa). In addition, the capacitive FPS can withstand over 20,000 times pressure loads without significant signal damping. Furthermore, the working mechanism of the capacitive FPS is illustrated by the finite element analysis (FEA) method and theoretical calculation. The application potential of the sensor in wearable electronics was demonstrated by human pulse wave monitoring and pressure mapping tests with a 4 × 6 sensor microarray.


Assuntos
Nanocompostos , Dispositivos Eletrônicos Vestíveis , Inteligência Artificial , Eletrodos , Eletrônica , Humanos , Pressão
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