212 research outputs found
An Antioxidant Phytotherapy to Rescue Neuronal Oxidative Stress
Oxidative stress is involved in the pathogenesis of ischemic neuronal injury. A Chinese herbal formula composed of Poria cocos (Chinese name: Fu Ling), Atractylodes macrocephala (Chinese name: Bai Zhu) and Angelica sinensis (Chinese names: Danggui, Dong quai, Donggui; Korean name: Danggwi) (FBD), has been proved to be beneficial in the treatment of cerebral ischemia/reperfusion (I/R).This study was carried out to evaluate the protective effect of FBD against neuronal oxidative stress in vivo and in vitro. Rat I/R were established by middle cerebral artery occlusion (MCAO) for 1 h, followed by 24 h reperfusion. MCAO led to significant depletion in superoxide dismutase and glutathione and rise in lipid peroxidation (LPO) and nitric oxide in brain. The neurological deficit and brain infarction were also significantly elevated by MCAO as compared with sham-operated group. All the brain oxidative stress and damage were significantly attenuated by 7 days pretreatment with the aqueous extract of FBD (250 mg kg−1, p.o.). Moreover, cerebrospinal fluid sampled from FBD-pretreated rats protected PC12 cells against oxidative insult induced by 0.2 mM hydrogen peroxide, in a concentration and time-dependent manner (IC50 10.6%, ET50 1.2 h). However, aqueous extract of FBD just slightly scavenged superoxide anion radical generated in xanthine–xanthine oxidase system (IC50 2.4 mg ml−1) and hydroxyl radical generated in Fenton reaction system (IC50 3.6 mg ml−1). In conclusion, FBD was a distinct antioxidant phytotherapy to rescue neuronal oxidative stress, through blocking LPO, restoring endogenous antioxidant system, but not scavenging free radicals
Modeling and Simulation of Gas Emission Based on Recursive Modified Elman Neural Network
For the purpose of achieving more effective prediction of the absolute gas emission quantity, this paper puts forward a new model based on the hidden recurrent feedback Elman. The recursive part of classic Elman cannot be adjusted because it is fixed. To a certain extent, this drawback affects the approximation ability of the Elman, so this paper adds the correction factors in recursive part and uses the error feedback to determine the parameters. The stability of the recursive modified Elman neural network is proved in the sense of Lyapunov stability theory, and the optimal learning rate is given. With the historical data of mine actual monitoring to experiment and analysis, the results show that the recursive modified Elman neural network model can effectively predict the gas emission and improve the accuracy and efficiency of prediction compared with the classic Elman prediction model
Bile dynamics within the biliary tract and microfluidic-based bile component detection: A review
Bilestones are solid masses found in the gallbladder or biliary tract, which
block the normal bile flow and eventually result in severe life-threatening
complications. Studies have shown that bilestone formation may be related to
bile flow dynamics and the concentration level of bile components. The bile
flow dynamics in the biliary tract play a critical role in disclosing the
mechanism of bile stasis and transportation. The concentration of bile
composition is closely associated with processes such as nucleation and
crystallization. Recently, microfluidic-based biosensors have been favored for
multiple advantages over traditional bench-top detection assays for their less
sample consumption, portability, low cost, and high sensitivity for real-time
detection. Here, we reviewed the developments in bile dynamics study and
microfluidics-based bile component detection methods. These studies may provide
valuable insights into the bilestone formation mechanisms and better treatment,
alongside our opinions on the future development of in vitro lithotriptic drug
screening of bilestones and bile characterization tests
Focus on the Sound around You: Monaural Target Speaker Extraction via Distance and Speaker Information
Previously, Target Speaker Extraction (TSE) has yielded outstanding
performance in certain application scenarios for speech enhancement and source
separation. However, obtaining auxiliary speaker-related information is still
challenging in noisy environments with significant reverberation. inspired by
the recently proposed distance-based sound separation, we propose the near
sound (NS) extractor, which leverages distance information for TSE to reliably
extract speaker information without requiring previous speaker enrolment,
called speaker embedding self-enrollment (SESE). Full- & sub-band modeling is
introduced to enhance our NS-Extractor's adaptability towards environments with
significant reverberation. Experimental results on several cross-datasets
demonstrate the effectiveness of our improvements and the excellent performance
of our proposed NS-Extractor in different application scenarios.Comment: Accepted by InterSpeech202
In Vivo Blood Glucose Quantification Using Raman Spectroscopy
We here propose a novel Raman spectroscopy method that permits the noninvasive measurement of blood glucose concentration. To reduce the effects of the strong background signals produced by surrounding tissue and to obtain the fingerprint Raman lines formed by blood analytes, a laser was focused on the blood in vessels in the skin. The Raman spectra were collected transcutaneously. Characteristic peaks of glucose (1125 cm(-1)) and hemoglobin (1549 cm(-1)) were observed. Hemoglobin concentration served as an internal standard, and the ratio of the peaks that appeared at 1125 cm(-1) and 1549 cm(-1) peaks was used to calculate the concentration of blood glucose. We studied three mouse subjects whose blood glucose levels became elevated over a period of 2 hours using a glucose test assay. During the test, 25 Raman spectra were collected transcutaneously and glucose reference values were provided by a blood glucose meter. Results clearly showed the relationship between Raman intensity and concentration. The release curves were approximately linear with a correlation coefficient of 0.91. This noninvasive methodology may be useful for the study of blood glucose in vivo
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