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Ginkgo biloba is abundant in secondary metabolites, including flavonoids and terpenoids. While the majority of research has focused on the role of these compounds in disease resistance, their specific contribution to pathogen defense has been rarely explored. In this study, we collected root exudates from hydroponically cultivated ginkgo seedlings and conducted a metabolomic analysis. We identified several primary metabolites mainly comprising amino acids and nucleotides, while secondary metabolites consisted of various compounds, including bioactive compounds such as flavonoids and terpenoids. Focusing on the secondary metabolites with relatively higher abundance in the exudates, we selected a mixture of flavonoids and terpenoids for in vitro inhibition experiments against two soil-borne fungal pathogens, Fusarium oxysporum f. sp. cucumerinum that causes cucumber wilt and Rhizoctonia solani AG-8 that causes wheat root rot. The results indicated that the growth rate of both fungus cells was significantly reduced with the increasing concentration of the flavonoid and terpenoid mixture extracted from ginkgo and was completely inhibited at a concentration of 5 mg/mL. Further experiments revealed that this mixture of flavonoids and terpenoids had a destructive effect on the cellular structure of both fungi, thereby reducing cell viability and achieving an antifungal effect. These findings provide a foundation for further research into the use of ginkgo extracts in biological control.
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Previous studies have reported a high occurrence of contrast-associated acute kidney injury (CA-AKI) in myocardial infarction (MI) patients undergoing primary percutaneous coronary intervention (PCI). However, the data on CA-AKI in MI patients who underwent elective PCI are limited. To evaluate the incidence of CA-AKI in MI patients undergoing elective PCI. The data were sourced from the Iodixanol-AKI Registry of MI patients scheduled to undergo elective PCI in 8 medical centers from May 2020 to November 2021. The participants were divided into three groups: acute, prior, and multiple MI. The outcomes measured were CA-AKI and the composite endpoint of major adverse renal and cardiovascular events (MARCE). The incidence of CA-AKI was 4.46% (37/830) in the MI patients, 4.40% (7/159) in the acute MI patients, 4.41% (22/499) in the prior MI patients, and 4.65% (8/172) in the multiple MI patients. Of note, 36 patients (97.30%) at AKI stage 1, and only 1 patient at AKI stage 2. There was no difference in the incidence of CA-AKI (P = 0.991) among the three groups. Multivariate regression analysis revealed that the independent risk factors for CA-AKI were diabetes and an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2. MARCE occurred in 3.4% (28/830) of the total patients and was not associated with either any subgroup of patients with MI or AKI. The incidence of CA-AKI was low and mainly limited to mildly impaired renal function in MI patients undergoing elective PCI.
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As a probiotic, Weizmannia coagulans (W. coagulans) is often used in food and medicine to regulate intestinal flora and exert anti-inflammatory effects. In this study, the anti-acne efficacy and mechanism of extracellular proteins (YTCY-EPs) from W. coagulans YTCY strain are analyzed. The main components of YTCY-EPs, extracted and separated from the fermentation broth, are peptides ranging from 1.51 to 11.44 kDa, accounting for about 80%. Among the peptides identified by LC/MS-MS, YTCY_A-F possess the properties of antimicrobial peptides, while YTCY_1-4 possess antioxidative properties. These peptides have a strong effect on Cutibacterium acnes (C. acnes) and significantly inhibit Staphylococcus aureus. The inhibition rate of biofilm adhesion of YT-EPs to C. acnes reached 50% under the MIC. It was found that YTCY-EPs possess strong antioxidant and anti-inflammatory properties. It can effectively reduce active oxygen nearly 3 times and can reduce the downstream TLR2/NF-κB and MAPKs/AP-1 pathways by regulating the nuclear translocation of NF-κB and AP-1 in vitro. The transcriptional expression of inflammatory cytokines, inflammatory chemokines, and matrix metalloproteinase genes is also regulated, thereby slowing the recruitment of inflammatory cells and the development of inflammation, and increasing keratinocyte mobility. In addition, the expression levels of inflammatory factors and matrix metalloproteinases in the rabbit ears with acne problems that were tested with YTCY-EPs were significantly reduced, and it was obviously observed that the rabbit ear inflammation, acne, and keratinization problems were repaired. The results of this study prove that YTCY-EPs can be used as a potential anti-acne raw material in cosmetics.
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Ginkgo biloba (ginkgo) leaves have medicinal value due to their high levels of secondary metabolites, such as flavonoids. We found that the flavonoid content in ginkgo leaves increases significantly at high altitudes (Qinghai-Tibet Plateau). Considering that high UV-B radiation is among the key environmental characteristics of the Qinghai-Tibet Plateau, we carried out simulated UV-B treatments on ginkgo seedlings and found that the flavonoid content of the leaves increased significantly following the treatments. Combined with results from our previous studies, we determined that the transcription factor GbHY5 may play a key role in responses to UV-B radiation. Overexpression of GbHY5 significantly promoted the accumulation of flavonoids in both ginkgo callus and Arabidopsis thaliana. Furthermore, yeast two-hybrid and real-time quantitative PCR showed that GbHY5 promoted the expression of GbMYB1 by interacting with GbMYB1 protein. Overexpression of GbMYB1 in ginkgo callus and A. thaliana also significantly promoted flavonoid biosynthesis. GbFLS encodes a key enzyme in flavonoid biosynthesis, and its promoter has binding elements of GbHY5 and GbMYB1. A dual-luciferase reporter assay indicated that while GbHY5 and GbMYB1 activated the expression of GbFLS individually, their co-expression achieved greater activation. Our analyses reveal the molecular mechanisms by which the UV-B-induced GbHY5-GbMYB1-GbFLS module promotes flavonoid biosynthesis in ginkgo, and they provide insight into the use of UV-B radiation to enhance the flavonoid content of ginkgo leaves.
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OBJECTIVE: To evaluate iodixanol-associated acute kidney injury (AKI) and prognosis in patients undergoing elective percutaneous coronary intervention (PCI). METHODS: Patients undergoing elective PCI and iodixanol administration were prospectively enrolled in 8 centers between May 2020 and November 2021. The primary endpoint was AKI, defined as an increase in SCr of ≥ 0.3 mg/dL (26.4 µmol/L) or relative elevation ≥ 50% from baseline in the 48-72 h after PCI. Prognosis evaluations included the major adverse renal and cardiovascular events (MARCE): all-cause mortality, new-onset renal replacement therapy (NRRT), non-fatal myocardial infarction, and non-fatal stroke. AKI predictors were identified using multivariable logistic regression and associations between AKI and outcomes were examined using Cox regression. RESULTS: A total of 3630 patients were included in the final analysis and 2.9% of patients (107/3,630) suffered AKI. Among them, 95.3% (102/107) of AKI were stage 1, and 4.6% (5/107) of stage 2. The multivariable analysis indicated that age over 75-year-old, diabetes, NT-pro-BNP > 300 pg/mL, hemoglobin < 110 g/L, eGFR < 60 mL/min/1.73m2, and diuretics were independently associated with AKI (p < 0.05). After a median follow-up of 13 months, MARCE occurred in 3.6% (131/3630) of the study population, and their incidence was higher in AKI (9.4%, 10/107) vs. non-AKI patients (3.4%, 121/3,523). However, after multivariable adjustment, there was no statistically significant association between AKI and MARCE (p = 0.382). CONCLUSIONS: In patients undergoing elective PCI, cases of iodixanol-associated AKI were mostly mild and, after multivariable adjustment, held no statistically significant association with MARCE on mid-term follow-up. CLINICAL RELEVANCE STATEMENT: The incidence of iodixanol-associated AKI was low and mainly limited to mild renal impairment in patients undergoing elective PCI. Physicians should provide adequate contrast for coronary artery evaluation and, at the same time, minimize the contrast volume. KEY POINTS: ⢠The incidence of iodixanol-associated acute kidney injury was low and mostly limited to mild renal impairment. ⢠Iodixanol administration had no statistically significant impact on the major adverse renal and cardiovascular events in patients undergoing elective percutaneous coronary intervention.
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Injúria Renal Aguda , Infarto do Miocárdio , Intervenção Coronária Percutânea , Humanos , Idoso , Intervenção Coronária Percutânea/efeitos adversos , Meios de Contraste/efeitos adversos , Estudos Prospectivos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/epidemiologia , Prognóstico , Infarto do Miocárdio/etiologia , Fatores de RiscoRESUMO
Dongcai is loved for its delicious flavor and nutritional value. The microorganisms in Dongcai play a vital role in their flavor, quality, and safety, and the microbial communities of Dongcai vary greatly from region to region. However, it remains unknown what the predominant microorganisms are in different traditional Dongcai and how they affect its flavor. The objective of this study is to explore the microbial diversity of traditional fermented Dongcai in three representative Chinese regions (Tianjin, Sichuan, and Guangzhou) and further assess their microbial functions. The microbial diversity of fermented Dongcai in Guangdong has the lowest diversity compared to fermented Dongcai in Sichuan, which has the highest. The distribution of the main genera of fermented Dongcai varies from region to region, but Carnimonas, Staphylococcus, Pseudomonas, Sphingomonas, Burkholderia-Caballeronia-Paraburkholderia, and Rhodococcus are the dominant genera in common. In addition, halophilic bacteria (HAB, i.e., Halomonas Bacillus, Virgibacillus, etc.) and lactic acid bacteria (LAB, i.e., Weissella and Lactobacillus) are also highly abundant. Of these, Burkholderia-Caballeronia-Paraburkholderia, Rhodococcus, Sphingomonas, Ralstonia, and Chromohalobacter are dominant in the Sichuan samples. In the Tianjin samples, Lactobacillus, Weissella, Virgibacillus, Enterobacter, Klebsiella, and Pseudomonas are the most abundant. Predictions of microbial metabolic function reveal that carbohydrates, amino acids, polyketides, lipids, and other secondary metabolites are abundantly available for biosynthesis. In addition, the different flavors of the three types of Dongcai may be due to the fact that the abundance of HAB and LAB shows a significant positive correlation with the amounts of important metabolites (e.g., salt, acid, amino nitrogen, and sugar). These results contribute to our understanding of the link between the distinctive flavors of different types of Dongcai and the microorganisms they contain and will also provide a reference for the relationship between microbial communities and flavor substances in semi-fermented pickles.
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This study investigated the effects of Lactobacillus curvatus fermentation on the oxidative stress attenuating effects of Euryale ferox on H2O2-induced human skin fibroblasts (HSF). The results showed that Lactobacillus curvatus fermentation (i) increases the content of the various bioactive components of Euryale ferox and is found to have smaller molecular weights of polysaccharides and polypeptides; (ii) increases the overall intracellular and extracellular antioxidant capacity of H2O2-induced HSF while reducing reactive oxygen species (ROS) levels. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) all showed simultaneous increases in activity. Aside from that, the Nrf2 and MAPK signaling pathways are activated to regulate downstream-associated proteins such as the Bax/Bcl-2 protein ratio, matrix metalloproteinase 1 (MMP-1) activity, and human type I collagen (COL-1). These results suggested that the fermentation of Euryale ferox with Lactobacillus curvatus enhances its antioxidant capacity and attenuates apoptosis and senescence caused by oxidative stress.
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OBJECTIVE: To compare the clinical efficacy between acupuncture combined with western medication and simple western medication for ocular myasthenia gravis (OMG), and to explore its possible mechanism. METHODS: A total of 60 patients of ocular myasthenia gravis were randomized into an acupuncture combined with western medication group (30 cases, 1 case dropped off) and a western medication group (30 cases, 2 cases dropped off). Oral pyridostigmine bromide tablet and prednisone acetate tablet were given in the western medication group. On the basis of the treatment in the western medication group, Tongdu Tiaoqi acupuncture (acupuncture for unblocking the governor vessel and regulating qi ) was applied at Baihui (GV 20), Fengfu (GV 16), Hegu (LI 4), Zusanli (ST 36), etc. in the acupuncture combined with western medication group, once a day, 6 days a week. The treatment was given 8 weeks in both groups. Before and after treatment, the OMG clinical absolute score was observed, electrophysiological indexes of orbicularis oculi (value of mean jitter, percentage of jitter >55 µs and percentage of blocks) were measured by single-fiber electromyography (SFEMG), serum levels of acetylcholine receptor antibody (AChR-Ab), interferon-gamma (IFN-γ) and interleukin-4 (IL-4) were detected by ELISA method. RESULTS: After treatment, the OMG clinical absolute scores, values of mean jitter, percentages of jitter >55 µs, percentages of blocks and serum levels of AChR-Ab, IFN-γ and IL-4 were decreased compared before treatment in both groups (P<0.05), and those in the acupuncture combined with western medication group were lower than the western medication group (P<0.05). CONCLUSION: Acupuncture combined with western medication can effectively improve ptosis, palpebra superior fatigability, eye movement disorder and neuromuscular junction dysfunction in patients with ocular myasthenia gravis, the therapeutic effect is superior to simple western medication. Its mechanism may be related to down-regulating serum levels of AChR-Ab, IFN-γ and IL-4 and promoting the recovery of orbicularis oculi function.
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Terapia por Acupuntura , Miastenia Gravis , Músculos Faciais , Humanos , Interferon gama , Interleucina-4 , Miastenia Gravis/tratamento farmacológicoRESUMO
OBJECTIVE: The Auditory brainstem response (ABR) can provide valuable information on the function of the auditory pathway. However, the ABR signal has a very small amplitude, and it is easily submerged in different background noises with large amplitude. Conventional ABR extraction methods such as time-domain averaging (TDA) and Kalman filter (KF) were greatly affected by noise intensity, and the result relies on the empirical settings of parameters. ABR extraction method that can automatically adjust parameters to adapt different background noises was needed. METHODS: An adaptive Kalman filtering (AKF) based ABR signal extraction method was proposed, in which two recursive rules were introduced to constantly update the parameters according to the real-time noise properties. It was used for ABR extraction from recordings in noises with different orders of larger magnitude. RESULTS: The AKF method demonstrated the best performance in obtaining reliable ABR waveform morphologies in the presence of large EMG noises compared with traditional methods of TDA or KF. It could extract satisfactory ABR signal with fewer trials of acoustic stimulus repetition, even from noise 10000 times larger than ABR signal. The AKF results also showed smaller absolute errors and higher correlation coefficients with the target ABR signal when different types (gum chewing, mouth opening and milk drinking) or levels of noises were introduced. CONCLUSION: The proposed AKF method is a great candidate to increase the robustness of current ABR measurements. SIGNIFICANCE: It could provide reduced testing time and relaxed recording conditions for ABR and other evoked potentials extraction.
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Potenciais Evocados Auditivos do Tronco Encefálico , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Limiar Auditivo/fisiologia , Estimulação Acústica/métodosRESUMO
The impact of JPEG compression on deep learning (DL) in image classification is revisited. Given an underlying deep neural network (DNN) pre-trained with pristine ImageNet images, it is demonstrated that, if, for any original image, one can select, among its many JPEG compressed versions including its original version, a suitable version as an input to the underlying DNN, then the classification accuracy of the underlying DNN can be improved significantly while the size in bits of the selected input is, on average, reduced dramatically in comparison with the original image. This is in contrast to the conventional understanding that JPEG compression generally degrades the classification accuracy of DL. Specifically, for each original image, consider its 10 JPEG compressed versions with their quality factor (QF) values from {100,90,80,70,60,50,40,30,20,10}. Under the assumption that the ground truth label of the original image is known at the time of selecting an input, but unknown to the underlying DNN, we present a selector called Highest Rank Selector (HRS). It is shown that HRS is optimal in the sense of achieving the highest Top k accuracy on any set of images for any k among all possible selectors. When the underlying DNN is Inception V3 or ResNet-50 V2, HRS improves, on average, the Top 1 classification accuracy and Top 5 classification accuracy on the whole ImageNet validation dataset by 5.6% and 1.9%, respectively, while reducing the input size in bits dramatically-the compression ratio (CR) between the size of the original images and the size of the selected input images by HRS is 8 for the whole ImageNet validation dataset. When the ground truth label of the original image is unknown at the time of selection, we further propose a new convolutional neural network (CNN) topology which is based on the underlying DNN and takes the original image and its 10 JPEG compressed versions as 11 parallel inputs. It is demonstrated that the proposed new CNN topology, even when partially trained, can consistently improve the Top 1 accuracy of Inception V3 and ResNet-50 V2 by approximately 0.4% and the Top 5 accuracy of Inception V3 and ResNet-50 V2 by 0.32% and 0.2%, respectively. Other selectors without the knowledge of the ground truth label of the original image are also presented. They maintain the Top 1 accuracy, the Top 5 accuracy, or the Top 1 and Top 5 accuracy of the underlying DNN, while achieving CRs of 8.8, 3.3, and 3.1, respectively.
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Towards eliminating stimulus artifacts, alternating polarity stimuli have been widely adopted in eliciting the auditory brainstem response. However, considering the difference in the physiologic basis of the positive and negative polarity stimuli on the auditory system, it is unclear whether alternating polarity stimuli would adversely affect the auditory brainstem response characteristics. This research proposes a new polarity method for stimulus artifacts elimination, Sum polarity, that separately utilized the rarefaction and condensation stimuli and then summed the two evoked responses. We compared the waveform morphology and latencies of the auditory brainstem responses evoked by familiar stimuli (including click, tone-burst, and chirp) with different polarity methods in normal-hearing subjects to investigate the new method's effectiveness. The experimental results showed that alternating polarity of the click and chirp had little effect on the auditory brainstem response. In contrast, alternating polarity affected the waveform morphology and latencies of the auditory brainstem responses to the low-frequency tone-burst, with the effect decreasing as the stimulus frequency increased. These results demonstrated the performance of any polarity method is related to the characteristics of the stimulus signal itself, and no polarity method is optimal for all types of stimuli. Based on the analysis of experimental results, a fixed polarity and alternating polarity were recommended for the click and chirp auditory brainstem responses, respectively. Furthermore, considering the apparent latency differences between the responses to opposite polarity stimuli, the Sum polarity was suggested for the tone-burst auditory brainstem responses. Moreover, this work verified the feasibility of the Sum polarity, which offers another choice for eliminating stimulus artifacts in an evoked potential acquisition.
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Percepção Auditiva/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Objective. The auditory brainstem response (ABR) audiometry is a means of assessing the functional status of the auditory neural pathway in the clinic. The conventional click ABR test lacks good neural synchrony and it mainly evaluates high-frequency hearing while the common tone-burst ABR test only detects hearing loss of a certain frequency at a time. Additionally, the existing chirp stimuli are designed based on average data of cochlear characteristics, ignoring individual differences amongst subjects.Approach. Therefore, this study designed a new stimulus approach based on a sweep-tone concept with a time variant and spectrum characteristics that could be customized based on an individual's cochlear characteristics. To validate the efficiency of the proposed method, we compared its performance with the click and tone-bursts using ABR recordings from 11 normal-hearing adults.Main results. Experimental results showed that the proposed sweep-tone ABR achieved a higher amplitude compared with those elicited by the click and tone-bursts. When the stimulus level or rate was varied, the sweep-tone ABR consistently elicited a larger response than the corresponding click ABR. Moreover, the sweep-tone ABR appeared earlier than the click ABR under the same conditions. Specifically, the mean wave V peak-to-peak amplitude of the sweep-tone ABR was 1.3 times that of the click ABR at 70 dB nHL (normal hearing level) and a rate of 20 s-1, in which the former saved 40% of test time.Significance. In summary, the proposed sweep-tone approach is found to be more efficient than the traditional click and tone-burst in eliciting ABR.
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Potenciais Evocados Auditivos do Tronco Encefálico , Audição , Estimulação Acústica/métodos , Adulto , Limiar Auditivo/fisiologia , Cóclea/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Audição/fisiologia , HumanosRESUMO
INTRODUCTION: Auditory brainstem response (ABR) is one of the commonly used methods in clinical settings to evaluate the hearing sensitivity and auditory function. The current ABR measurement usually adopts click sound as the stimuli. However, there may be partial ABR amplitude attenuation due to the delay characteristics of the cochlear traveling wave along the basilar membrane. To solve that problem, a swept-tone method was proposed, in which the show-up time of different frequency components was adjusted to compensate the delay characteristics of the cochlear basilar membrane; therefore, different ABR subcomponents of different frequencies were synchronized. METHODS: The normal hearing group, moderate sensorineural hearing loss group, and severe sensorineural hearing loss group underwent click ABR and swept-tone ABR with different stimulus intensities. The latencies and amplitudes of waves I, III, and V in 2 detections were recorded. RESULTS: It was found that the latency of each of the recorded I, III, and V waves detected by swept-tone ABR was shorter than that by click ABR in both the control group and experimental groups. In addition, the amplitude of each of the recorded I, III, and V waves, except V waves under 60 dB nHL in the moderate sensorineural hearing loss group, detected by swept-tone ABR was larger than that by click ABR. The results also showed that the swept-tone ABR could measure the visible V waves at lower stimulus levels in the severe sensorineural hearing loss group. CONCLUSION: Swept-tone improves the ABR waveforms and helps to obtain more accurate threshold to some extent. Therefore, the proposed swept-tone ABR may provide a new solution for better morphology of ABR waveform, which can help to make more accurate diagnosis about the hearing functionality in the clinic.
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Limiar Auditivo/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Perda Auditiva Neurossensorial/fisiopatologia , Estimulação Acústica/métodos , Adolescente , Adulto , Feminino , Testes Auditivos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
T helper 17 (Th17) cells that express interleukin-17 (IL-17) play a key role in various inflammatory diseases, such as multiple sclerosis (MS), and its animal model experimental autoimmune encephalomyelitis (EAE). The retinoic acid receptor-related orphan receptors γt (RORγt) have an indispensable effect on the differentiation of this cell type, and are thus considered a valuable target in the treatment of Th17-related disorders. In this study, we found that eriodictyol (EDT), a natural flavonoid abundant in citrus fruits and peanuts, was located directly in the binding pocket of RORγt, and induced a conformational change that resulted in the effective suppression of the receptor's activity, thus offering insight into the transcriptional inhibition of RORγt-dependent genes. Consistent with this, EDT dose-dependently (5-10 µM) blocked murine Th17 differentiation, and markedly reduced IL-17A secretion in vitro. Furthermore, this compound has been found to have novel properties for directly inhibiting Th1 cell development and promoting Treg cell differentiation at high doses (≥10 µM). EDT administration significantly decreased the clinical severity in the EAE model, with inhibited demyelination and reduced inflammatory responses in the periphery and in the central nervous system (CNS). In the adoptive transfer model, EDT also remarkably suppressed the Th17 cell infiltration and pathogenicity. Collectively, our data demonstrated that EDT, as an agent for the pharmacological inhibition of RORγt, has great potential for immunomodulation, and for use in the treatment of Th17-mediated autoimmune disease.
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Diferenciação Celular/efeitos dos fármacos , Encefalomielite Autoimune Experimental/tratamento farmacológico , Flavanonas/farmacologia , Interleucina-17/metabolismo , Células Th17/imunologia , Transferência Adotiva , Animais , Diferenciação Celular/imunologia , Relação Dose-Resposta Imunológica , Encefalomielite Autoimune Experimental/imunologia , Camundongos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/antagonistas & inibidores , Células Th17/citologiaRESUMO
Auditory brainstem response (ABR) is an objective method via which hearing loss could be detected. ABR induced by click, a broadband signal, is generally considered as the gold standard. However, due to the inherent delay of the cochlear traveling wave, click cannot excite the entire cochlear basement membrane at the same time, leading to the attenuation of the induced ABR waveform. In order to resolve this limitation, a sweep-tone-based stimulus that reconstructs the arrival time of different frequency components with respect to the delay characteristics of cochlear basement membrane was designed and used to induce ABR in this study. Subsequently, we compared the performance of the proposed sweep-tone-induced ABR method and the commonly adopted click induced ABR at different test levels and different stimulus rates. And the obtained results showed that the waveform morphology of sweep-tone-induced ABR was significantly better than that of click induced ABR across different test levels and stimulus rates. Moreover, compared to the click induced ABR at different sweeps, we found that the proposed sweep-tone-induced ABR effectively induced the ABR waveform at a relatively faster rate. Hence, the proposed sweep-tone-induced ABR approach provides a new method to improve the sensitivity of ABR detection in hearing loss.
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Potenciais Evocados Auditivos do Tronco Encefálico , Perda Auditiva , Estimulação Acústica , Adulto , Limiar Auditivo , Cóclea , Testes Auditivos , HumanosRESUMO
Physiological signals such as ECG and EMG are closely related with human health and a long term monitoring of the physiological signals would be beneficial to detect possible disorders at the early stage. The wet electrodes currently used in the clinics require adhesives gels to record high-quality signals, which might cause discomfort of the patients and introduce some risk of skin allergy. Non-contact capacitive electrodes that can be operated without skin contact have been developed in previous studies, but these electrodes were rigid with electronic components on the back, which might not be an optimal solution for long term healthcare monitoring. In this study, a flexible non-contact electrode without any electronic components on both sides was designed for the long term acquisition of bioelectrical signals to maximize subject comfort. The flexible electrode was made up of multi-layer flexible printed circuits (FPC) materials and could be bent according to the local shape to achieve better non-contact capacitive coupling with the skin. The performance of the proposed flexible electrode was compared with that of the conventional wet electrodes in different signal recording conditions. The results showed that the proposed non-contact flexible electrode can capture high quality ECG and EMG signals, and its performance was comparable to the commonly used wet electrodes. This study might provide a reliable solution with great patient comfort for the long-term monitoring of biological signals.
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Eletrodos , Adesivos , Humanos , PeleRESUMO
BACKGROUND: Swallowing is a continuous process with substantive interdependencies among different muscles, and it plays a significant role in our daily life. The aim of this study was to propose a novel technique based on high-density surface electromyography (HD sEMG) for the evaluation of normal swallowing functions. METHODS: A total of 96 electrodes were placed on the front neck to acquire myoelectric signals from 12 healthy subjects while they were performing different swallowing tasks. HD sEMG energy maps were constructed based on the root mean square values to visualize muscular activities during swallowing. The effects of different volumes, viscosities, and head postures on the normal swallowing process were systemically investigated by using the energy maps. RESULTS: The results showed that the HD sEMG energy maps could provide detailed spatial and temporal properties of the muscle electrical activity, and visualize the muscle contractions that closely related to the swallowing function. The energy maps also showed that the swallowing time and effort was also explicitly affected by the volume and viscosity of the bolus. The concentration of the muscular activities shifted to the opposite side when the subjects turned their head to either side. CONCLUSIONS: The proposed method could provide an alternative method to physiologically evaluate the dynamic characteristics of normal swallowing and had the advantage of providing a full picture of how different muscle activities cooperate in time and location. The findings from this study suggested that the HD sEMG technique might be a useful tool for fast screening and objective assessment of swallowing disorders or dysphagia.
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Deglutição/fisiologia , Eletromiografia/métodos , Adulto , Eletrodos , Eletromiografia/instrumentação , Feminino , Cabeça , Humanos , Masculino , Contração Muscular , Postura , Processamento de Sinais Assistido por Computador , Viscosidade , Adulto JovemRESUMO
A liquid chromatography-mass spectrometry method was developed for the simultaneous determination of ronidazole (RNZ), metronidazole (MNZ) and dimetridazole (DMZ) residues in swine liver. Following liquid-liquid extraction, the HLB solid-phase extraction was used for further purification. The targets were detected by atmospheric pressure chemical ionization (APCI) following the reverse phase liquid chromatography separation. Consequently, the detection limits for the method were 0.5 microg/kg for MNZ, 1.0 microg/kg for RNZ and 0.5 microg/kg for DMZ, respectively. The accuracies were determined using swine liver samples fortified at levels of 0.5, 1, 2, and 4 microg/kg and the mean recoveries of the analytes were between 66% and 81%.