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1.
Sensors (Basel) ; 22(17)2022 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-36081149

RESUMEN

Heart rate (HR) and respiratory rate (RR) are two vital parameters of the body medically used for diagnosing short/long-term illness. Out-of-the-body, non-skin-contact HR/RR measurement remains a challenge due to imprecise readings. "Invisible" wearables integrated into day-to-day garments have the potential to produce precise readings with a comfortable user experience. Sleep studies and patient monitoring benefit from "Invisibles" due to longer wearability without significant discomfort. This paper suggests a novel method to reduce the footprint of sleep monitoring devices. We use a single silver-coated nylon fabric band integrated into a substrate of a standard cotton/nylon garment as a resistive elastomer sensor to measure air and blood volume change across the chest. We introduce a novel event-based architecture to process data at the edge device and describe two algorithms to calculate real-time HR/RR on ARM Cortex-M3 and Cortex-M4F microcontrollers. RR estimations show a sensitivity of 99.03% and a precision of 99.03% for identifying individual respiratory peaks. The two algorithms used for HR calculation show a mean absolute error of 0.81 ± 0.97 and 0.86±0.61 beats/min compared with a gold standard ECG-based HR. The event-based algorithm converts the respiratory/pulse waveform into instantaneous events, therefore reducing the data size by 40-140 times and requiring 33% less power to process and transfer data. Furthermore, we show that events hold enough information to reconstruct the original waveform, retaining pulse and respiratory activity. We suggest fabric sensors and event-based algorithms would drastically reduce the device footprint and increase the performance for HR/RR estimations during sleep studies, providing a better user experience.


Asunto(s)
Nylons , Frecuencia Respiratoria , Frecuencia Cardíaca/fisiología , Humanos , Polisomnografía , Frecuencia Respiratoria/fisiología , Sueño
2.
Infect Immun ; 89(9): e0015721, 2021 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-34061623

RESUMEN

Zebrafish (Danio rerio) is an attractive model organism to use for an array of scientific studies, including host-microbe interactions. Zebrafish contain a core (i.e., consistently detected) intestinal microbiome consisting primarily of Proteobacteria. Furthermore, this core intestinal microbiome is plastic and can be significantly altered due to external factors. Zebrafish are particularly useful for the study of aquatic microbes that can colonize vertebrate hosts, including Vibrio cholerae. As an intestinal pathogen, V. cholerae must colonize the intestine of an exposed host for pathogenicity to occur. Members of the resident intestinal microbial community likely must be reduced or eliminated by V. cholerae for colonization, and subsequent disease, to occur. Many studies have explored a variety of aspects of the pathogenic effects of V. cholerae on zebrafish and other model organisms but few have researched how a V. cholerae infection changes the resident intestinal microbiome. In this study, 16S rRNA gene sequencing was used to examine how five genetically diverse V. cholerae strains alter the intestinal microbiome following an infection. We found that V. cholerae colonization induced significant changes in the zebrafish intestinal microbiome. Notably, changes in the microbial profile were significantly different from each other, based on the particular strain of V. cholerae used to infect zebrafish hosts. We conclude that V. cholerae significantly modulates the zebrafish intestinal microbiota to enable colonization and that specific microbes that are targeted depend on the V. cholerae genotype.


Asunto(s)
Cólera/microbiología , Susceptibilidad a Enfermedades , Microbioma Gastrointestinal , Interacciones Huésped-Patógeno , Interacciones Microbianas , Vibrio cholerae/fisiología , Animales , Modelos Animales de Enfermedad , Metagenómica/métodos , ARN Ribosómico 16S , Pez Cebra
3.
Infect Immun ; 89(9): e0015121, 2021 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-34097462

RESUMEN

Zebrafish (Danio rerio) are an attractive model organism for a variety of scientific studies, including host-microbe interactions. The organism is particularly useful for the study of aquatic microbes that can colonize vertebrate hosts, including Vibrio cholerae, an intestinal pathogen. V. cholerae must colonize the intestine of an exposed host for pathogenicity to occur. While numerous studies have explored various aspects of the pathogenic effects of V. cholerae on zebrafish and other model organisms, few, if any, have examined how a V. cholerae infection alters the resident intestinal microbiome and the role of the type six secretion system (T6SS) in that process. In this study, 16S rRNA gene sequencing was utilized to investigate how strains of V. cholerae both with and without the T6SS alter the aforementioned microbial profiles following an infection. V. cholerae infection induced significant changes in the zebrafish intestinal microbiome, and while not necessary for colonization, the T6SS was important for inducing mucin secretion, a marker for diarrhea. Additional salient differences to the microbiome were observed based on the presence or absence of the T6SS in the V. cholerae utilized for challenging the zebrafish hosts. We conclude that V. cholerae significantly modulates the zebrafish intestinal microbiome to enable colonization and that the T6SS is important for pathogenesis induced by the examined V. cholerae strains. Furthermore, the presence or absence of T6SS differentially and significantly affected the composition and structure of the intestinal microbiome, with an increased abundance of other Vibrio bacteria observed in the absence of V. cholerae T6SS.


Asunto(s)
Cólera/microbiología , Microbioma Gastrointestinal , Interacciones Microbiota-Huesped , Interacciones Huésped-Patógeno , Sistemas de Secreción Tipo VI/fisiología , Vibrio cholerae/fisiología , Animales , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Metagenómica/métodos , ARN Ribosómico 16S , Pez Cebra
4.
J Neurosci Res ; 99(11): 3066-3083, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34510506

RESUMEN

Galvanic vestibular stimulation (GVS) has been shown to improve vestibular function potentially via stochastic resonance, however, it remains unknown how central vestibular nuclei process these signals. In vivo work applying electrical stimuli to the vestibular apparatus of animals has shown changes in neuronal discharge at the level of the primary vestibular afferents and hair cells. This study aimed to determine the cellular impacts of stochastic, sinusoidal, and stochastic + sinusoidal stimuli on individual medial vestibular nucleus (MVN) neurons of male and female C57BL/6 mice. All stimuli increased the irregularity of MVN neuronal discharge, while differentially affecting neuronal gain. This suggests that the heterogeneous MVN neuronal population (marked by differential expression of ion channels), may influence the impact of electrical stimuli on neuronal discharge. Neuronal subtypes showed increased variability of neuronal firing, where Type A and B neurons experienced the largest gain changes in response to stochastic and sinusoidal stimuli. Type C neurons were the least affected regarding neuronal firing variability and gain changes. The membrane potential (MP) of neurons was altered by sinusoidal and stochastic + sinusoidal stimuli, with Type B and C neuronal MP significantly affected. These results indicate that GVS-like electrical stimuli impact MVN neuronal discharge differentially, likely as a result of heterogeneous ion channel expression.


Asunto(s)
Neuronas , Núcleos Vestibulares , Animales , Femenino , Masculino , Potenciales de la Membrana , Ratones , Ratones Endogámicos C57BL , Neuronas/fisiología
5.
PLoS Pathog ; 15(8): e1008010, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31449551

RESUMEN

Klebsiella pneumoniae (Kp), one of the most common causes of healthcare-associated infections, increases patient morbidity, mortality, and hospitalization costs. Kp must acquire nutrients from the host for successful infection; however, the host is able to prevent bacterial nutrient acquisition through multiple systems. This includes the innate immune protein lipocalin 2 (Lcn2), which prevents Kp iron acquisition. To identify novel Lcn2-dependent Kp factors that mediate evasion of nutritional immunity during lung infection, we undertook an InSeq study using a pool of >20,000 transposon mutants administered to Lcn2+/+ and Lcn2-/- mice. Comparing transposon mutant frequencies between mouse genotypes, we identified the Kp citrate synthase, GltA, as potentially interacting with Lcn2, and this novel finding was independently validated. Interestingly, in vitro studies suggest that this interaction is not direct. Given that GltA is involved in oxidative metabolism, we screened the ability of this mutant to use a variety of carbon and nitrogen sources. The results indicated that the gltA mutant has a distinct amino acid auxotrophy rendering it reliant upon glutamate family amino acids for growth. Deletion of Lcn2 from the host leads to increased amino acid levels in bronchioloalveolar lavage fluid, corresponding to increased fitness of the gltA mutant in vivo and ex vivo. Accordingly, addition of glutamate family amino acids to Lcn2+/+ bronchioloalveolar lavage fluid rescued growth of the gltA mutant. Using a variety of mouse models of infection, we show that GltA is an organ-specific fitness factor required for complete fitness in the spleen, liver, and gut, but dispensable in the bloodstream. Similar to bronchioloalveolar lavage fluid, addition of glutamate family amino acids to Lcn2+/+ organ lysates was sufficient to rescue the loss of gltA. Together, this study describes a critical role for GltA in Kp infection and provides unique insight into how metabolic flexibility impacts bacterial fitness during infection.


Asunto(s)
Citrato (si)-Sintasa/metabolismo , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/crecimiento & desarrollo , Lipocalina 2/metabolismo , Lipocalina 2/fisiología , Animales , Citrato (si)-Sintasa/genética , Modelos Animales de Enfermedad , Humanos , Infecciones por Klebsiella/metabolismo , Klebsiella pneumoniae/enzimología , Lipocalina 2/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
6.
Sensors (Basel) ; 20(6)2020 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-32178307

RESUMEN

The comfortable, continuous monitoring of vital parameters is still a challenge. The long-term measurement of respiration and cardiovascular signals is required to diagnose cardiovascular and respiratory diseases. Similarly, sleep quality assessment and the recovery period following acute treatments require long-term vital parameter datalogging. To address these requirements, we have developed "VitalCore", a wearable continuous vital parameter monitoring device in the form of a T-shirt targeting the uninterrupted monitoring of respiration, pulse, and actigraphy. VitalCore uses polymer-based stretchable resistive bands as the primary sensor to capture breathing and pulse patterns from chest expansion. The carbon black-impregnated polymer is implemented in a U-shaped configuration and attached to the T-shirt with "interfacing" material along with the accompanying electronics. In this paper, VitalCore is bench tested and compared to gold standard respiration and pulse measurements to verify its functionality and further to assess the quality of data captured during sleep and during light exercise (walking). We show that these polymer-based sensors could identify respiratory peaks with a sensitivity of 99.44%, precision of 96.23%, and false-negative rate of 0.557% during sleep. We also show that this T-shirt configuration allows the wearer to sleep in all sleeping positions with a negligible difference of data quality. The device was also able to capture breathing during gait with 88.9%-100% accuracy in respiratory peak detection.


Asunto(s)
Elastómeros/química , Electrocardiografía/métodos , Sueño/fisiología , Hollín/química , Electrocardiografía/instrumentación , Frecuencia Cardíaca , Humanos , Frecuencia Respiratoria , Caminata , Dispositivos Electrónicos Vestibles
7.
Sensors (Basel) ; 20(1)2019 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-31877893

RESUMEN

Stretchable conductive materials are originally conceived as radio frequency (RF) and electromagnetic interference (EMI) shielding materials, and, under stretch, they generally function as distributed strain-gauges. These commercially available conductive elastomers have found their space in low power health monitoring systems, for example, to monitor respiratory and cardiac functions. Conductive elastomers do not behave linearly due to material constraints; hence, when used as a sensor, a full characterisation to identify ideal operating ranges are required. In this paper, we studied how the continuous stretch cycles affected the material electrical and physical properties in different embodiment impressed by bodily volume change. We simulated the stretch associated with breathing using a bespoke stress rig to ensure reproducibility of results. The stretch rig is capable of providing constant sinusoidal waves in the physiological ranges of extension and frequency. The material performances is evaluated assessing the total harmonic distortion (THD), signal-to-noise ratio (SNR), correlation coefficient, peak to peak (P-P) amplitude, accuracy, repeatability, hysteresis, delay, and washability. The results showed that, among the three controlled variables, stretch length, stretch frequency and fabric width, the most significant factor to the signal quality is the stretch length. The ideal working region is within 2% of the original length. The material cut in strips of > 3 show more reliable to handle a variety of stretch parameter without losing its internal characteristics and electrical properties.


Asunto(s)
Monitoreo Fisiológico/métodos , Conductividad Eléctrica , Procesamiento Automatizado de Datos , Monitoreo Fisiológico/instrumentación , Reproducibilidad de los Resultados , Relación Señal-Ruido
8.
Sensors (Basel) ; 19(8)2019 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-31010184

RESUMEN

Monitoring of vital signs is critical for patient triage and management. Principal assessments of patient conditions include respiratory rate heart/pulse rate and blood oxygen saturation. However, these assessments are usually carried out with multiple sensors placed in different body locations. The aim of this paper is to identify a single location on the human anatomy whereby a single 1 cm × 1 cm non-invasive sensor could simultaneously measure heart rate (HR), blood oxygen saturation (SpO2), and respiration rate (RR), at rest and while walking. To evaluate the best anatomical location, we analytically compared eight anatomical locations for photoplethysmography (PPG) sensors simultaneously acquired by a single microprocessor at rest and while walking, with a comparison to a commercial pulse oximeter and respiration rate ground truth. Our results show that the forehead produced the most accurate results for HR and SpO2 both at rest and walking, however, it had poor RR results. The finger recorded similar results for HR and SpO2, however, it had more accurate RR results. Overall, we found the finger to be the best location for measurement of all three parameters at rest; however, no site was identified as capable of measuring all parameters while walking.

9.
Infect Immun ; 86(12)2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30249745

RESUMEN

The Vibrio cholerae O1 serogroup is responsible for pandemic cholera and is divided into the classical and El Tor biotypes. Classical V. cholerae produces acid when using glucose as a carbon source, whereas El Tor V. cholerae produces the neutral product acetoin when using glucose as a carbon source. An earlier study demonstrated that Escherichia coli strains that metabolize glucose to acidic by-products drastically reduced the survival of V. cholerae strains in vitro In the present study, zebrafish were fed 1% glucose and either inoculated with single V. cholerae or E. coli strains or coinfected with both V. cholerae and E. coli A significant decrease in classical biotype colonization was observed after glucose feeding due to acid production in the zebrafish intestine. El Tor colonization was unaffected by glucose alone. However, the El Tor strain exhibited significantly lower colonization of the zebrafish when either of the acid-producing E. coli strains was coinoculated in the presence of glucose. An E. coli sugar transport mutant had no effect on V. cholerae colonization even in presence of glucose. Glucose and E. coli produced a prophylactic effect on El Tor colonization in zebrafish when E. coli was inoculated before V. cholerae infection. Thus, the probiotic feeding of E. coli inhibits V. cholerae colonization in a natural host. This suggests that a similar inhibitory effect could be seen in cholera patients, especially if a glucose-based oral rehydration solution (ORS) is administered in combination with probiotic E. coli during cholera treatment.


Asunto(s)
Cólera/prevención & control , Escherichia coli/metabolismo , Glucosa/metabolismo , Intestinos/microbiología , Vibrio cholerae O1/patogenicidad , Ácidos/metabolismo , Animales , Antibiosis , Carga Bacteriana , Transporte Biológico , Cólera/microbiología , Escherichia coli/fisiología , Probióticos/farmacología , Pez Cebra/microbiología
10.
Biomed Eng Online ; 17(1): 61, 2018 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-29751811

RESUMEN

BACKGROUND: Worldwide, at least 200 million people are affected by peripheral vascular diseases (PVDs), including peripheral arterial disease (PAD), chronic venous insufficiency (CVI) and deep vein thrombosis (DVT). The high prevalence and serious consequences of PVDs have led to the development of several diagnostic tools and clinical guidelines to assist timely diagnosis and patient management. Given the increasing number of diagnostic methods available, a comprehensive review of available technologies is timely in order to understand their limitations and direct future development effort. MAIN BODY: This paper reviews the available diagnostic methods for PAD, CVI, and DVT with a focus on non-invasive modalities. Each method is critically evaluated in terms of sensitivity, specificity, accuracy, ease of use, procedure time duration, and training requirements where applicable. CONCLUSION: This review emphasizes the limitations of existing methods, highlighting a latent need for the development of new non-invasive, efficient diagnostic methods. Some newly emerging technologies are identified, in particular wearable sensors, which demonstrate considerable potential to address the need for simple, cost-effective, accurate and timely diagnosis of PVDs.


Asunto(s)
Técnicas y Procedimientos Diagnósticos , Extremidad Inferior , Enfermedades Vasculares Periféricas/diagnóstico , Monitores de Presión Sanguínea , Humanos , Enfermedades Vasculares Periféricas/diagnóstico por imagen , Enfermedades Vasculares Periféricas/fisiopatología , Pletismografía , Ultrasonografía Doppler
11.
Appl Environ Microbiol ; 83(16)2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28625997

RESUMEN

Vibrio cholerae is the etiological agent of cholera, an acute intestinal infection in humans characterized by voluminous watery diarrhea. Cholera is spread through ingestion of contaminated food or water, primarily in developing countries that lack the proper infrastructure for proper water and sewage treatment. Vibrio cholerae is an aquatic bacterium that inhabits coastal and estuarine areas, and it is known to have several environmental reservoirs, including fish. Our laboratory has recently described the use of the zebrafish as a new animal model for the study of V. cholerae intestinal colonization, pathogenesis, and transmission. As early as 6 h after exposure to V. cholerae, zebrafish develop diarrhea. Prior work in our laboratory has shown that this is not due to the action of cholera toxin. We hypothesize that accessory toxins produced by V. cholerae are the cause of diarrhea in infected zebrafish. In order to assess the effects of accessory toxins in the zebrafish, it was necessary to develop a method of quantifying diarrheal volume as a measure of pathogenesis. Here, we have adapted cell density, protein, and mucin assays, along with enumeration of V. cholerae in the zebrafish intestinal tract and in the infection water, to achieve this goal. Combined, these assays should help us determine which toxins have the greatest diarrheagenic effect in fish and, consequently, which toxins may play a role in environmental transmission.IMPORTANCE Identification of the accessory toxins that cause diarrhea in zebrafish can help us understand more about the role of fish in the wild as aquatic reservoirs for V. cholerae It is plausible that accessory toxins can act to prolong colonization and subsequent shedding of V. cholerae back into the environment, thus perpetuating and facilitating transmission during an outbreak. It is also possible that accessory toxins help to maintain low levels of intestinal colonization in fish, giving V. cholerae an advantage when environmental conditions are not optimal for survival in the water. Studies such as this one are critical because fish could be an overlooked source of cholera transmission in the environment.

12.
Biomed Eng Online ; 16(1): 118, 2017 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-28974217

RESUMEN

BACKGROUND: Peripheral neuropathic desensitization associated with aging, diabetes, alcoholism and HIV/AIDS, affects tens of millions of people worldwide, and there is little or no treatment available to improve sensory function. Recent studies that apply imperceptible continuous vibration or electrical stimulation have shown promise in improving sensitivity in both diseased and healthy participants. This class of interventions only has an effect during application, necessitating the design of a wearable device for everyday use. We present a circuit that allows for a low-power, low-cost and small form factor implementation of a current stimulator for the continuous application of subthreshold currents. RESULTS: This circuit acts as a voltage-to-current converter and has been tested to drive + 1 to - 1 mA into a 60 k[Formula: see text] load from DC to 1 kHz. Driving a 60 k[Formula: see text] load with a 2 mA peak-to-peak 1 kHz sinusoid, the circuit draws less than 21 mA from a 9 V source. The minimum operating current of the circuit is less than 12 mA. Voltage compliance is ± 60 V with just 1.02 mA drawn by the high voltage current drive circuitry. The circuit was implemented as a compact 46 mm × 21 mm two-layer PCB highlighting its potential for use in a body-worn device. CONCLUSIONS: No design to the best of our knowledge presents comparably low quiescent power with such high voltage compliance. This makes the design uniquely appropriate for low-power transcutaneous current stimulation in wearable applications. Further development of driving and instrumentation circuitry is recommended.


Asunto(s)
Estimulación Eléctrica/instrumentación , Dispositivos Electrónicos Vestibles , Costos y Análisis de Costo , Piel
13.
PLoS One ; 19(5): e0303516, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38728330

RESUMEN

Increasingly prevalent, nontuberculous mycobacteria (NTM) infections affect approximately 20% of people with cystic fibrosis (CF). Previous studies of CF sputum identified lower levels of the host metabolite itaconate in those infected with NTM. Itaconate can inhibit the growth of M. tuberculosis (MTB) in vitro via the inhibition of the glyoxylate cycle enzyme (ICL), but its impact on NTM is unclear. To test itaconic acid's (IA) effect on NTM growth, laboratory and CF clinical strains of Mycobacterium abscessus and Mycobacterium avium were cultured in 7H9 minimal media supplemented with 1-10 mM of IA and short-chain fatty acids (SCFA). M. avium and M. abscessus grew when supplemented with SCFAs, whereas the addition of IA (≥ 10 mM) completely inhibited NTM growth. NTM supplemented with acetate or propionate and 5 mM IA displayed slower growth than NTM cultured with SCFA and ≤ 1 mM of IA. However, IA's inhibition of NTM was pH dependent; as similar and higher quantities (100 mM) of pH adjusted IA (pH 7) did not inhibit growth in vitro, while in an acidic minimal media (pH 6.1), 1 to 5 mM of non-pH adjusted IA inhibited growth. None of the examined isolates displayed the ability to utilize IA as a carbon source, and IA added to M. abscessus isocitrate lyase (ICL) decreased enzymatic activity. Lastly, the addition of cell-permeable 4-octyl itaconate (4-OI) to THP-1 cells enhanced NTM clearance, demonstrating a potential role for IA/itaconate in host defense against NTM infections.


Asunto(s)
Succinatos , Succinatos/farmacología , Succinatos/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Micobacterias no Tuberculosas/efectos de los fármacos , Micobacterias no Tuberculosas/crecimiento & desarrollo , Células THP-1 , Infecciones por Mycobacterium no Tuberculosas/microbiología , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Mycobacterium avium/efectos de los fármacos , Mycobacterium avium/crecimiento & desarrollo , Mycobacterium abscessus/efectos de los fármacos , Mycobacterium abscessus/crecimiento & desarrollo , Mycobacterium abscessus/metabolismo
14.
Sci Rep ; 14(1): 1327, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-38225286

RESUMEN

Peripheral vascular diseases (PVDs) represent a significant burden on global human health and healthcare systems. With continued growth in obesity and diabetes, it is likely that the incidence of these conditions will increase. As many PVDs remain undiagnosed, low-cost and easy to use diagnostic methods are required. This work uses newly developed wearable electro-resistive morphic sensors to assess venous and arterial competence in the lower limbs of 36 healthy subjects. Comparison of this HeMo device was made to currently available benchtop light reflection rheography and photoplethymography devices. Results indicate that HeMo can detect the physiological signals of interest for both chronic venous insufficiency and peripheral arterial disease and all subjects were interpreted as healthy by each system. However, measurement repeatability of HeMo was highlighted as an issue that requires further system development. Furthermore, as HeMo captures changes in a section of limb circumference due to changes in underlying blood movement, rather than at a single point, the recorded signal is typically damped by comparison. This factor should be considered in any future developments.


Asunto(s)
Enfermedad Arterial Periférica , Insuficiencia Venosa , Dispositivos Electrónicos Vestibles , Humanos , Insuficiencia Venosa/diagnóstico , Venas , Extremidad Inferior , Enfermedad Arterial Periférica/diagnóstico
15.
Artículo en Inglés | MEDLINE | ID: mdl-38083229

RESUMEN

Transcranial doppler (TCD) ultrasound probes are an invaluable tool in cerebral blood flow (CBF) studies. Their operation demands maintaining consistent pose on the subject throughout the experimental protocol. However, the displacement of the TCD probe during vestibular studies is common and substantially prolongs the experiment or even terminates it. This is a significant challenge for integrating motion-based vestibular studies with CBF investigations. In response, a mechatronics system is designed to allow remote repositioning of the TCD probe during data collection experiments while the subject is wearing a head mounted virtual reality (VR) display and seated in a vestibular disorientation device. This paper presents the design, prototype, and operation of this mechatronics apparatus.Clinical Relevance- The mechatronics apparatus of this paper can enable motion-based vestibular studies that entail the use of CBF velocity measurement and head-mounted virtual reality display.


Asunto(s)
Vestíbulo del Laberinto , Realidad Virtual , Ultrasonografía Doppler Transcraneal/métodos , Circulación Cerebrovascular/fisiología , Vestíbulo del Laberinto/diagnóstico por imagen , Movimiento (Física)
16.
Biosensors (Basel) ; 13(7)2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37504102

RESUMEN

Effective monitoring of respiratory disturbances during sleep requires a sensor capable of accurately capturing chest movements or airflow displacement. Gold-standard monitoring of sleep and breathing through polysomnography achieves this task through dedicated chest/abdomen bands, thermistors, and nasal flow sensors, and more detailed physiology, evaluations via a nasal mask, pneumotachograph, and airway pressure sensors. However, these measurement approaches can be invasive and time-consuming to perform and analyze. This work compares the performance of a non-invasive wearable stretchable morphic sensor, which does not require direct skin contact, embedded in a t-shirt worn by 32 volunteer participants (26 males, 6 females) with sleep-disordered breathing who performed a detailed, overnight in-laboratory sleep study. Direct comparison of computed respiratory parameters from morphic sensors versus traditional polysomnography had approximately 95% (95 ± 0.7) accuracy. These findings confirm that novel wearable morphic sensors provide a viable alternative to non-invasively and simultaneously capture respiratory rate and chest and abdominal motions.


Asunto(s)
Frecuencia Respiratoria , Síndromes de la Apnea del Sueño , Masculino , Femenino , Humanos , Polisomnografía , Sueño/fisiología , Síndromes de la Apnea del Sueño/diagnóstico , Respiración
17.
mSphere ; 7(3): e0010422, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35477313

RESUMEN

Nontuberculous mycobacterial (NTM) pulmonary infections in people with cystic fibrosis (CF) are associated with significant morbidity and mortality and are increasing in prevalence. Host risk factors for NTM infection in CF are largely unknown. We hypothesize that the airway microbiota represents a host risk factor for NTM infection. In this study, 69 sputum samples were collected from 59 people with CF; 42 samples from 32 subjects with NTM infection (14 samples collected before incident NTM infection and 28 samples collected following incident NTM infection) were compared to 27 samples from 27 subjects without NTM infection. Sputum samples were analyzed with 16S rRNA gene sequencing and metabolomics. A supervised classification and correlation analysis framework (sparse partial least-squares discriminant analysis [sPLS-DA]) was used to identify correlations between the microbial and metabolomic profiles of the NTM cases compared to the NTM-negative controls. Several metabolites significantly differed in the NTM cases compared to controls, including decreased levels of tryptophan-associated and branched-chain amino acid metabolites, while compounds involved in phospholipid metabolism displayed increased levels. When the metabolome and microbiome data were integrated by sPLS-DA, the models and component ordinations showed separation between the NTM and control samples. While this study could not determine if the observed differences in sputum metabolites between the cohorts reflect metabolic changes that occurred as a result of the NTM infection or metabolic features that contributed to NTM acquisition, it is hypothesis generating for future work to investigate host and bacterial community factors that may contribute to NTM infection risk in CF. IMPORTANCE Host risk factors for nontuberculous mycobacterial (NTM) infection in people with cystic fibrosis (CF) are largely unclear. The goal of this study was to help identify potential host and bacterial community risk factors for NTM infection in people with CF, using microbiome and metabolome data from CF sputum samples. The data obtained in this study identified several metabolic profile differences in sputum associated with NTM infection in CF, including 2-methylcitrate/homocitrate and selected ceramides. These findings represent potential risk factors and therapeutic targets for preventing and/or treating NTM infections in people with CF.


Asunto(s)
Fibrosis Quística , Infecciones por Mycobacterium no Tuberculosas , Infecciones Oportunistas , Bacterias , Fibrosis Quística/complicaciones , Fibrosis Quística/microbiología , Humanos , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Micobacterias no Tuberculosas , ARN Ribosómico 16S/genética , Esputo/microbiología
18.
JMIR Ment Health ; 9(9): e37354, 2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36069848

RESUMEN

BACKGROUND: An anticipated surge in mental health service demand related to COVID-19 has motivated the use of novel methods of care to meet demand, given workforce limitations. Digital health technologies in the form of self-tracking technology have been identified as a potential avenue, provided sufficient evidence exists to support their effectiveness in mental health contexts. OBJECTIVE: This literature review aims to identify current and potential physiological or physiologically related monitoring capabilities of the Apple Watch relevant to mental health monitoring and examine the accuracy and validation status of these measures and their implications for mental health treatment. METHODS: A literature review was conducted from June 2021 to July 2021 of both published and gray literature pertaining to the Apple Watch, mental health, and physiology. The literature review identified studies validating the sensor capabilities of the Apple Watch. RESULTS: A total of 5583 paper titles were identified, with 115 (2.06%) reviewed in full. Of these 115 papers, 19 (16.5%) were related to Apple Watch validation or comparison studies. Most studies showed that the Apple Watch could measure heart rate acceptably with increased errors in case of movement. Accurate energy expenditure measurements are difficult for most wearables, with the Apple Watch generally providing the best results compared with peers, despite overestimation. Heart rate variability measurements were found to have gaps in data but were able to detect mild mental stress. Activity monitoring with step counting showed good agreement, although wheelchair use was found to be prone to overestimation and poor performance on overground tasks. Atrial fibrillation detection showed mixed results, in part because of a high inconclusive result rate, but may be useful for ongoing monitoring. No studies recorded validation of the Sleep app feature; however, accelerometer-based sleep monitoring showed high accuracy and sensitivity in detecting sleep. CONCLUSIONS: The results are encouraging regarding the application of the Apple Watch in mental health, particularly as heart rate variability is a key indicator of changes in both physical and emotional states. Particular benefits may be derived through avoidance of recall bias and collection of supporting ecological context data. However, a lack of methodologically robust and replicated evidence of user benefit, a supportive health economic analysis, and concerns about personal health information remain key factors that must be addressed to enable broader uptake.

19.
Biochem Biophys Res Commun ; 409(3): 372-7, 2011 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-21545791

RESUMEN

Two anticancer agents, LCL85 and photodynamic therapy (PDT) were combined to test whether the combination PDT/LCL85 evokes changes in the sphingolipid (SL) profile and promotes cell death. Treatment of SCCVII mouse squamous carcinoma cells using the silicone phthalocyanine Pc 4 for PDT induced increases in the prodeath global ceramides/dihydroceramides (DHceramides), and no changes in the prosurvival sphingosine-1-phosphate (S1P). In contrast, after LCL85, the levels of most ceramides and DHceramides were reduced, whereas the levels of S1P were increased. After PDT/LCL85 the levels of global ceramides and DHceramides, and of S1P, were restored to resting levels. PDT/LCL85 also enhanced the levels of C18-, C20-, and C20:1-ceramide, and C18-DHceramide. Treatment with PDT, with or without LCL85, led to substantial reductions in sphingosine levels. PDT/LCL85 induced enhanced autophagy and caspase-3 activation. None of the treatments affected short-term viability of cells. In contrast, long-term clonogenic survival was reduced not only after PDT or LCL85, but even more after PDT/LCL85. Overall, our data show that short-term exposure to PDT/LCL85 led to distinct signature effects on the SL profile, enhanced autophagy, and caspase-3 activation without cell death. Long-term exposure to PDT/LCL85 enhanced overall cell killing, supporting translational potential of PDT/LCL85.


Asunto(s)
Antineoplásicos/uso terapéutico , Autofagia , Carcinoma de Células Escamosas/tratamiento farmacológico , Caspasa 3/metabolismo , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Indoles/uso terapéutico , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Propanolaminas/uso terapéutico , Compuestos de Piridinio/uso terapéutico , Esfingolípidos/metabolismo , Animales , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Ceramidas/metabolismo , Neoplasias de Cabeza y Cuello/metabolismo , Humanos , Lisofosfolípidos/metabolismo , Ratones , Esfingosina/análogos & derivados , Esfingosina/metabolismo
20.
Cardiovasc Digit Health J ; 2(2): 137-147, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35265900

RESUMEN

Background: Wearable technologies are increasingly popular. Yet their use remains low by older adults, who may stand the greatest benefit of use. While there is an abundance of research examining the performance, accuracy, specificity, and sensitivity of wearable devices, many barriers remain and need to be addressed to optimize uptake in clinical practice. There is a paucity of research exploring factors that help to understand barriers and facilitators to inform acceptance, adoption, wearability, and sustainability of use. Objectives: (1) To explore the perceptions and experiences of older adults and health professionals about using wearable cardiac monitoring technologies, and (2) to identify barriers and facilitators of acceptance and uptake of these devices in clinical practice. Methods: A systematic review with a qualitative meta-synthesis was undertaken. Results: A total of 7 original research studies were included.Four interrelated themes emerged: (1) trust, including safety, and confidence; (2) functionality and affordability; (3) risks; and (4) assurance. Conclusion: There are many barriers and facilitators to the adoption of wearable devices based on experiences of older adults, health professionals, and carers. Most significant factors related to the design aspects of the devices, appropriate and timely feedback, user-friendly technology, and issues related to affordability and cost.

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