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1.
Anal Chem ; 93(27): 9299-9303, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34184865

RESUMO

The development of precise medicine requires diagnostic probes to simultaneously satisfy an excellent detection limit and a wide linear analysis range because of enormous individual-discrepancy of disease biomarker concentrations, yet it remains challenging. Herein, an upconverison nanoprobe with a luminescence ratio flexibly tailored was designed for ultrasensitive monitoring exhaled nitric oxide to indicate the clinical course of asthma. Two independent emissions from the same nanoprobe can be discretionarily modulated to vary their intensity ratios for adapting different analysis requirements. Delightfully, this novel nanoprobe demonstrated a 100-fold lower detection limit compared with the traditional ratiometric fluorescence manner and a more broad linear detection range from the subpart per billion (ppb) level to hundreds of ppb. This ratio-adjustable fluorescence detection strategy holds great potential for miscellaneous disease diagnosis applications.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Luminescência
2.
Acupunct Med ; 39(5): 423-431, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33280396

RESUMO

OBJECTIVE: Post-operative cognitive dysfunction (POCD) is a common post-surgical complication, which is associated with increased costs and extended hospital stays. Recently, interest in acupuncture as a potential therapy for POCD has grown. The objective of this meta-analysis was to assess the effectiveness of acupuncture for POCD. METHODS: PubMed, Embase, CENTRAL, Medline, Web of Science, CNKI, Wanfang, and VIP databases were searched through March 2018. Randomized controlled trials (RCTs) in which patients with POCD treated with acupuncture (acupuncture group) were compared with those receiving a no treatment control were included. Meta-analyses were conducted using Review Manager 5.3. RESULTS: Sixteen studies containing 1241 participants were included. POCD incidence in the acupuncture group was significantly lower than that in the control groups on the first (odds ratio (OR) = 0.32, 95% confidence interval (CI) = 0.23-0.45) and third (OR = 0.41, 95% CI = 0.30-0.56) post-operative days, with no statistically significant difference on the seventh day (OR = 0.58, 95% CI = 0.32-1.04). Acupuncture therapy also improved mini-mental state examination (MMSE) scores on the first (mean difference (MD) = 3.28, 95% CI = 2.79-3.77) and third (MD = 2.52, 95% CI = 2.18-2.87) post-operative days, with no effect on the seventh (MD = 0.14, 95% CI = -0.24 to 0.51). Visual analogue scale (VAS) scores on the first post-operative day were not impacted by acupuncture but were likely associated with post-operative nausea and vomiting on the seventh post-operative day. With respect to methodological quality, most RCTs were found to have an unclear risk of bias. CONCLUSION: Acupuncture may successfully treat/prevent POCD. However, the current evidence is limited and further research is needed.


Assuntos
Terapia por Acupuntura , Disfunção Cognitiva/terapia , Complicações Pós-Operatórias/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Escala Visual Analógica
4.
IEEE Trans Image Process ; 29: 100-115, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31329559

RESUMO

The inverse synthetic aperture radar (ISAR) imaging technique of a moving target with sparse sampling data has attracted wide attention due to its ability to reduce the data collection burden. However, traditional low-rank or 2D compressive sensing (CS)-based ISAR imaging methods can handle the random sampling or the separable sampling data only. When the specific data collection condition cannot be satisfied, low-rank or 2D CS-based methods cannot provide satisfactory imaging results any more. To remedy this problem, in this paper, we proposed a joint low-rank and sparsity priors' constrained model for ISAR imaging with various sparse data patterns. This model is inspired by the facts that the received radar data have a low-rank property and the ISAR image is sparse on the specific dictionary. Two reconstruction algorithms to solve the double priors' constrained optimization problem are developed under the alternative direction method of multipliers (ADMM) framework with the help of augmented Lagrange multipliers (ALM). Results on simulation data and real data show that the proposed methods are quite effective in recovering missing samples and focused image and perform better than the matrix completion-based method and the sparse representation-based method when dealing with the various kinds of sparse sampling data.

5.
Chin Med J (Engl) ; 132(24): 2934-2940, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31855963

RESUMO

BACKGROUND: The pathogenesis of multiple sclerosis (MS) is mediated primarily by T cells, but most studies of MS and its animal model, experimental autoimmune encephalomyelitis (EAE), have focused on CD4 T cells. The aims of the current study were to determine the pathological interrelationship between CD4 and CD8 autoreactive T cells in MS/EAE. METHODS: Female C57BL/6 mice (n = 20) were induced by myelin oligodendrocyte glycoprotein (MOG)35-55 peptide. At 14 days after immunization, T cells were isolated from the spleen and purified as CD4 and CD8 T cells by using CD4 and CD8 isolation kits, and then the purity was determined by flow cytometric analysis. These cells were stimulated by MOG35-55 peptide and applied to proliferation assays. The interferon-gamma (IFN-γ) and interleukin (IL)-4 secretion of supernatant of cultured CD4 and CD8 T cells were measured by enzyme-linked immunosorbent assays (ELISA). For adoptive transfer, recipient mice were injected with MOG35-55-specific CD8 or CD4 T cells. EAE clinical course was measured by EAE score at 0-5 scale and spinal cord was examined by staining with hematoxylin and eosin and Luxol fast blue staining. RESULTS: CD8CD3 and CD4CD3 cells were 86% and 94% pure of total CD3 cells after CD8/CD4 bead enrichment, respectively. These cells were stimulated by MOG35-55 peptide and applied to proliferation assays. Although the CD8 T cells had a generally lower response to MOG35-55 than CD4 T cells, the response of CD8 T cells was not always dependent on CD4. CD8 T cell secreted less IFN-γ and IL-4 compared with CD4 T cells. EAE was induced in wildtype B6 naïve mice by adoptive transfer of MOG35-55-specific T cells from B6 active-induced EAE (aEAE) mice. A similar EAE score and slight inflammation and demyelination were found in naive B6 mice after transferring of CD8 T cells from immunized B6 mice compared with transfer of CD4 T cells. CONCLUSION: Our data suggest that CD8 autoreactive T cells in EAE have a lower encephalitogenic function but are unique and independent on pathogenic of EAE rather than their CD4 counterparts.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Encefalomielite Autoimune Experimental/imunologia , Glicoproteína Mielina-Oligodendrócito/imunologia , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/imunologia , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/etiologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Fragmentos de Peptídeos/imunologia
6.
Lab Anim ; 53(2): 160-168, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30049253

RESUMO

It is important to develop a feasible animal model of regional anesthesia other than sciatic nerve blockade for pharmacokinetic investigations of new local anesthetics or analgesia in upper extremity surgery. Herein, we explored a nerve stimulator (NS)-guided brachial plexus block (BPB) in a rat model. The anatomy of the brachial plexus in rats was delineated in cadavers, and various BPBs were examined. The puncture point was located 0.5-1.0 cm below the lateral one-third of the clavicle. The efficacy and safety of the NS-guided BPB were evaluated using an injection of 2% lidocaine or 0.5% bupivacaine in 16 live animals; saline injection was used as a control. Both sides of the brachial plexus were located successfully using the NS-guided technique. Sensory blockade (nociception assessment) and motor blockade (grasping and straightening tests) appeared after application of the two classical local anesthetics, but not normal saline. The motor and sensory blockade induced by bupivacaine exhibited a longer duration than that induced by lidocaine ( p < 0.05). All rats recovered uneventfully from general anesthesia and BPB. No abnormal results were found in pathological studies or behavioral observations. Thus, a rat model of NS-guided BPB was established, and BPB induced an overall reversible sensory and motor blockade in the thoracic limbs. Evaluation of the efficacy and safety demonstrated that this rat BPB model was feasible, reproducible, and safe.


Assuntos
Anestésicos Locais/farmacologia , Bloqueio do Plexo Braquial/métodos , Bupivacaína/farmacologia , Lidocaína/farmacologia , Ratos/fisiologia , Animais , Cadáver , Feminino , Humanos , Masculino , Modelos Animais , Ratos Sprague-Dawley
7.
J Clin Monit Comput ; 30(4): 467-73, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26178886

RESUMO

Continuous respiratory gas monitoring is an important tool for clinical monitoring. In particular, measurement of respiratory [Formula: see text] concentration and gasflow can reflect the status of a patient by providing parameters such as volume of carbon dioxide, end-tidal [Formula: see text] respiratory rate and alveolar deadspace. However, in the majority of previous work, [Formula: see text] concentration and gasflow have been studied separately. This study focuses on a mainstream system which simultaneously measures respiratory [Formula: see text] concentration and gasflow at the same location, allowing for volumetric capnography to be implemented. A non-dispersive infrared monitor is used to measure [Formula: see text] concentration and a differential pressure sensor is used to measure gasflow. In developing this new device, we designed a custom airway adapter which can be placed in line with the breathing circuit and accurately monitor relevant respiratory parameters. Because the airway adapter is used both for capnography and gasflow, our system reduces mechanical deadspace. The finite element method was used to design the airway adapter which can provide a strong differential pressure while reducing airway resistance. Statistical analysis using the coefficient of variation was performed to find the optimal driving voltage of the pressure transducer. Calibration between variations and flows was used to avoid pressure signal drift. We carried out targeted experiments using the proposed device and confirmed that the device can produce stable signals.


Assuntos
Capnografia/instrumentação , Dióxido de Carbono/análise , Monitorização Fisiológica/instrumentação , Capnografia/estatística & dados numéricos , Simulação por Computador , Desenho de Equipamento , Análise de Elementos Finitos , Humanos , Monitorização Fisiológica/estatística & dados numéricos , Respiração , Respiração Artificial , Processamento de Sinais Assistido por Computador , Transdutores de Pressão
8.
Sensors (Basel) ; 15(11): 29535-46, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26610511

RESUMO

Carbon monoxide (CO) burns or explodes at over-standard concentration. Hence, in this paper, a Wifi-based, real-time monitoring of a CO system is proposed for application in the construction industry, in which a sensor measuring node is designed by low-frequency modulation method to acquire CO concentration reliably, and a digital filtering method is adopted for noise filtering. According to the triangulation, the Wifi network is constructed to transmit information and determine the position of nodes. The measured data are displayed on a computer or smart phone by a graphical interface. The experiment shows that the monitoring system obtains excellent accuracy and stability in long-term continuous monitoring.

9.
Sensors (Basel) ; 15(8): 19618-32, 2015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26270665

RESUMO

Continuous respiratory monitoring is an important tool for clinical monitoring. Associated with the development of biomedical technology, it has become more and more important, especially in the measuring of gas flow and CO2 concentration, which can reflect the status of the patient. In this paper, a new type of biomedical device is presented, which uses low-power sensors with a piezoresistive silicon differential pressure sensor to measure gas flow and with a pyroelectric sensor to measure CO2 concentration simultaneously. For the portability of the biomedical device, the sensors and low-power measurement circuits are integrated together, and the airway tube also needs to be miniaturized. Circuits are designed to ensure the stability of the power source and to filter out the existing noise. Modulation technology is used to eliminate the fluctuations at the trough of the waveform of the CO2 concentration signal. Statistical analysis with the coefficient of variation was performed to find out the optimal driving voltage of the pressure transducer. Through targeted experiments, the biomedical device showed a high accuracy, with a measuring precision of 0.23 mmHg, and it worked continuously and stably, thus realizing the real-time monitoring of the status of patients.


Assuntos
Fontes de Energia Elétrica , Eletricidade , Equipamentos e Provisões , Monitorização Fisiológica/instrumentação , Respiração , Dióxido de Carbono/análise , Humanos , Pressão , Processamento de Sinais Assistido por Computador
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