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1.
Microorganisms ; 11(12)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38138064

RESUMO

Three strains of thermophilic green sulfur bacteria (GSB) are known; all are from microbial mats in hot springs in Rotorua, New Zealand (NZ) and belong to the species Chlorobaculum tepidum. Here, we describe diverse populations of GSB inhabiting Travel Lodge Spring (TLS) (NZ) and hot springs ranging from 36.1 °C to 51.1 °C in the Republic of the Philippines (PHL) and Yellowstone National Park (YNP), Wyoming, USA. Using targeted amplification and restriction fragment length polymorphism analysis, GSB 16S rRNA sequences were detected in mats in TLS, one PHL site, and three regions of YNP. GSB enrichments from YNP and PHL mats contained small, green, nonmotile rods possessing chlorosomes, chlorobactene, and bacteriochlorophyll c. Partial 16S rRNA gene sequences from YNP, NZ, and PHL mats and enrichments from YNP and PHL samples formed distinct phylogenetic clades, suggesting geographic isolation, and were associated with samples differing in temperature and pH, suggesting adaptations to these parameters. Sequences from enrichments and corresponding mats formed clades that were sometimes distinct, increasing the diversity detected. Sequence differences, monophyly, distribution patterns, and evolutionary simulation modeling support our discovery of at least four new putative moderately thermophilic Chlorobaculum species that grew rapidly at 40 °C to 44 °C.

2.
IEEE Trans Biomed Circuits Syst ; 10(2): 319-27, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25706824

RESUMO

This paper presents a vital sign detection sensor based on reflection coefficient variance from an antenna used in wireless communication devices. The near-field effect is estimated by performing 3D full-wave simulations using a dipole antenna and the magnitude variation of the reflection coefficient induced by human thorax movement due to heart and lungs is observed. The results support the possibility of vital sign detection based on the magnitude variation of the reflection coefficient from an antenna, which can be explained as a narrowband modulation scheme. In particular, a sensitivity enhancement method is proposed and analyzed, and experiments are carried out for heartbeat detection using a dipole antenna with the proposed system. Experimental results are compared between the direct detection and sensitivity enhancement detection schemes. FM signal is also applied to confirm that the proposed sensor works properly in conjunction with an existing communication system. The proposed cardiopulmonary detection sensor is implemented with off-the-shelf components at 2.4 GHz and excellent performance is obtained.


Assuntos
Técnicas Biossensoriais/instrumentação , Frequência Cardíaca , Taxa Respiratória , Tecnologia sem Fio/instrumentação , Impedância Elétrica , Desenho de Equipamento , Humanos , Sinais Vitais
3.
IEEE Trans Biomed Circuits Syst ; 10(2): 300-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25966481

RESUMO

This paper presents the development of a non-contact, nonintrusive wrist pulse sensor based on the near-field variation of an array resonator. A compact resonator and its array were designed and fabricated on flexible substrate. The reflection coefficient of the resonator can vary as a function of the distance between the resonator and the walls of the major arteries, and the corresponding variation is utilized to obtain heart rate information at the wrist. To detect very weak pulse signals from the main arteries, a sensitivity enhancement technique was devised using a radio frequency (RF) array resonator. The sensor system was implemented with an RF switch to combine or select appropriate signals from the resonator element and was tested using the 2.4 GHz ISM band. The results demonstrated the sensor system's excellent performance in both sequential and simultaneous detection schemes. The measurement results showed that a heartbeat pulse can be detected from both radial and ulnar arteries via the array resonators. Considering the high sensitivity and characteristics, the proposed detection system can be utilized as a wearable, long-term health monitoring device.


Assuntos
Técnicas Biossensoriais/instrumentação , Determinação da Frequência Cardíaca/instrumentação , Punho/fisiologia , Desenho de Equipamento , Humanos , Artéria Radial/fisiologia , Ondas de Rádio , Artéria Ulnar/fisiologia
4.
IEEE Trans Biomed Eng ; 62(11): 2568-75, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26057527

RESUMO

Novel nonintrusive technologies for wrist pulse detection have been developed and proposed as systems for sleep monitoring using three types of radio frequency (RF) sensors. The three types of RF sensors for heart rate measurement on wrist are a flexible RF single resonator, array resonators, and an injection-locked PLL resonator sensor. To verify the performance of the new RF systems, we compared heart rates between presleep time and postsleep onset time. Heart rates of ten subjects were measured using the RF systems during sleep. All three RF devices detected heart rates at 0.2 to 1 mm distance from the skin of the wrist over clothes made of cotton fabric. The wrist pulse signals of a flexible RF single resonator were consistent with the signals obtained by a portable piezoelectric transducer as a reference. Then, we confirmed that the heart rate after sleep onset time significantly decreased compared to before sleep. In conclusion, the RF system can be utilized as a noncontact nonintrusive method for measuring heart rates during sleep.


Assuntos
Vestuário , Frequência Cardíaca/fisiologia , Polissonografia/instrumentação , Polissonografia/métodos , Adulto , Desenho de Equipamento , Feminino , Humanos , Masculino , Ondas de Rádio , Processamento de Sinais Assistido por Computador , Punho/fisiologia
5.
Korean J Anesthesiol ; 60(2): 98-102, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21390164

RESUMO

BACKGROUND: Bilateral total knee arthroplasty is generally accompanied by a significant amount of blood loss. We investigated the relationship between the intensity of pain and the amount of blood loss in the early postoperative period after bilateral total knee arthroplasty. METHODS: A prospective study was conducted on 91 patients who underwent elective sequential bilateral total knee arthroplasty for osteoarthritis. All patients received combined spinal and epidural anesthesia. Patients were divided into three groups based on their scores on the verbal numerical rating scale (VNRS) for pain at 6 hours postoperatively. The VNRS was classified as follows; mild pain (n = 34, VNRS score 0-4), moderate pain (n = 24, VNRS score 5-6), and severe pain (n = 33, VNRS score 7-10). We compared the mean arterial pressures and the amount of blood loss during the first 24 postoperative hours in the three groups. Factors influencing postoperative blood loss were analyzed. RESULTS: Postoperative mean arterial pressures and blood loss were not different among the groups. Of the factors examined, the amount of postoperative blood loss was only dependent on the amount of intraoperative blood loss (P = 0.001). CONCLUSIONS: Early postoperative pain has no effect on postoperative blood pressure and the amount of blood loss after bilateral total knee arthroplasty. For postoperative blood loss, intraoperative blood loss is the main determinant.

6.
BMB Rep ; 43(5): 337-43, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20510017

RESUMO

Fenofibrate, an agonist of PPARalpha, plays an important role in activating many proteins catalyzing lipid metabolism, and it also has a considerable effect on improvement of insulin sensitivity in the diabetic condition. To investigate fenofibrate-dependent expression of peripheral tissue proteins in diabetes, we analyzed whole muscle or fat proteins of fenofibrate-fed OLETF rats, an animal model of type II diabetes, using 2-dimensional gel electrophoresis. We found that many proteins were specifically expressed in a fenofibrate-dependent manner in these diabetic rats. In particular, a functionally unknown C11orf59 protein was differentially expressed in the muscle tissues (about 5-fold increase) in fenofibrate-fed OLETF rats as compared to control rats. Additionally, the signal proteins phosphatidylethanolamine binding protein and IkB interacting protein were differentially regulated in the fenofibrate-treated adipose tissues. We suggest here that these proteins might be involved in controlling lipid or carbohydrate metabolism in diabetes via PPARalpha activation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Tecido Adiposo/química , Diabetes Mellitus Tipo 2/metabolismo , Fenofibrato/administração & dosagem , Hipolipemiantes/administração & dosagem , Proteínas Musculares/análise , Músculo Esquelético/química , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Proteoma/análise , Tecido Adiposo/efeitos dos fármacos , Animais , Dieta , Eletroforese em Gel Bidimensional , Proteínas Musculares/metabolismo , Músculo Esquelético/efeitos dos fármacos , PPAR alfa/metabolismo , Ratos , Ratos Endogâmicos OLETF , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
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