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Antibiotic contamination is becoming a prominent global issue. Therefore, sensitive, specific and simple technology is desirable the demand for antibiotics detection. Biosensors based on split aptamer has gradually attracted extensive attention for antibiotic detection due to its higher sensitivity, lower cost, false positive/negative avoidance and flexibility in sensor design. Although many of the reported split aptamers are antibiotics aptamers, the acquisition and mechanism of splitting is still unknow. In this review, six reported split aptamers in antibiotics are outlined, including Enrofloxacin, Kanamycin, Tetracycline, Tobramycin, Neomycin, Streptomycin, which have contributed to promote interest, awareness and thoughts into this emerging research field. The study introduced the pros and cons of split aptamers, summarized the assembly principle of split aptamer and discussed the intermolecular binding of antibiotic-aptamer complexes. In addition, the recent application of split aptamers in antibiotic detection are introduced. Split aptamers have a promising future in the design and development of biosensors for antibiotic detection in food and other field. The development of the antibiotic split aptamer meets many challenges including mechanism discovery, stability improvement and new biosensor development. It is believed that split aptamer could be a powerful molecular probe and plays an important role in aptamer biosensor. [ABSTRACT FROM AUTHOR]

[Obbectives] This study aimed to explore the effects of moxibustion at the Yanglingquan and Yinlingquan points on thickness of the left foot and synovial tissue inflammation of coHagen-induced arthritis (CIA) rats, and to explore the therapeutic effect of moxibustion at complementary acupoints on rheumatoid arthritis (RA). [Methods] Total 32 Wistar rats were selected. Among them, 8 rats were selected randomly using the randomized digital method a the blank control (K), and the remaining were subjected to modeling. After the succeesful establishment of the CIA model, the 24 rats were randomly and evenly divided into model group (M), Yanglingquan and Yinlingquan group (AB) and Shenshu and Zusanli group (CD). The rats in the moxibustion groups were subjected to bilateral synchronous moxibustion once every two days (2 mg refined moxa/cone, 5 cones/(point • d)), for total 10 times. The left plantar thicknes of each rat was measured before modeling, after modeling, and after the list intervention, respectively. After the last intervention, the situation of synovial tiisue inflammation in each rat of the treatment group was inspected. [Results] Compared with that of the control group, the left foot thicknes of each group of rats that were modeled a l incre/ed significantly (P <0. 05). And the synovial tiisue showed diferent degrees of inflammatory infiltration, fibrous hyperpl/ia, and angiogenes. After the intervention ended, compared with that in the M group, the left foot tliicknes in the AB and CD treatment groups reduced significantly (P <0. 05). The inflammatory infiltration, fibrous hyperplasia, and angiogenes of the synovial tiisue decreased. Between the two moxibustion groups, the thicknes of the left foot in group AB decreased compared with group CD (P < 0 . 0 5). The inflammatory infiltration, fibrous hyperplasia and angiogenes in group AB decre/ed compared with those in group CD. [Conclusions] Moxibustion at the complementary acupoints of Yanglingquan and Yinlingquan, Shenshu and Zusanli both showed good improvement effect on CIA rats. In terms of left foot tliicknes and synovial tissue inflammation, the treatment group AB was superior to the group CD, and the specific mechanism needs further study. [ABSTRACT FROM AUTHOR]

Rotor resistance identification has been well recognized as one of the most critical factors affecting the theoretical study and applications of AC motor's control for high performance variable frequency speed adjustment. This paper proposes a novel model for rotor resistance parameters identification based on Elman neural networks. Elman recurrent neural network is capable of performing nonlinear function approximation and possesses the ability of time-variable characteristic adaptation. Those influencing factors of specified parameter are analyzed, respectively, and various work states are covered to ensure the completeness of the training samples. Through signal preprocessing on samples and training dataset, different input parameters identifications with one network are compared and analyzed. The trained Elman neural network, applied in the identification model, is able to efficiently predict the rotor resistance in high accuracy. The simulation and experimental results show that the proposed method owns extensive adaptability and performs very well in its application to vector controlled induction motor. This identification method is able to enhance the performance of induction motor's variable-frequency speed regulation. [ABSTRACT FROM AUTHOR]

A reliable fault diagnostic system for gas turbine generator system (GTGS), which is complicated and inherent with many types of component faults, is essential to avoid the interruption of electricity supply. However, the GTGS diagnosis faces challenges in terms of the existence of simultaneous-fault diagnosis and high cost in acquiring the exponentially increased simultaneous-fault vibration signals for constructing the diagnostic system. This research proposes a new diagnostic framework combining feature extraction, pairwise-coupled probabilistic classifier, and decision threshold optimization. The feature extraction module adopts wavelet packet transform and time-domain statistical features to extract vibration signal features. Kernel principal component analysis is then applied to further reduce the redundant features. The features of single faults in a simultaneous-fault pattern are extracted and then detected using a probabilistic classifier, namely, pairwise-coupled relevance vector machine, which is trained with single-fault patterns only. Therefore, the training dataset of simultaneous-fault patterns is unnecessary. To optimize the decision threshold, this research proposes to use grid search method which can ensure a global solution as compared with traditional computational intelligence techniques. Experimental results show that the proposed framework performs well for both single-fault and simultaneous-fault diagnosis and is superior to the frameworks without feature extraction and pairwise coupling. [ABSTRACT FROM AUTHOR]

The effects of tea polyphenols and ultraviolet radiation on the growth and antioxidant activity of mung bean sprouts were investigated, followed by the changes in corresponding antioxidant enzyme activities and metabolite composition. The growth of mung bean sprouts was slightly decreased by tea polyphenols and ultraviolet radiation, but the antioxidant activity was increased. The activities of peroxidase and catalase were decreased, and the contents of vitamin C, γ-aminobutyric acid and total phenols were significantly increased by tea polyphenol treatment. While the activities of peroxidase and catalase increased by ultraviolet radiation with concomitant increase in the contents of vitamin C and total phenols. The mung bean sprouts produced following imposition of stressors such as tea polyphenols and ultraviolet radiation from stress conditions could be used as a potential functional food. [ABSTRACT FROM AUTHOR]

A cyano-bridged {FeIII2CoII2} complex exhibits reversible thermally and photoinduced intramolecular charge transfer. Its desolvated, MeOH-d4, and other analogues were compared to disclose the impact factors on the electron-transfer behavior of these {FeIII2CoII2} clusters. [ABSTRACT FROM AUTHOR]

Enhancement of alternative activation (M2) in microglia is a promising therapeutic target for microglia-mediated neuroinflammation. Shenqi Fuzheng Injection (SFI) is a clinical adjuvant treatment for cancer to reduce the side effects during cancer treatment, including boosting mood and improving appetite. However, the mechanism of SFI's effects on central symptoms is not clear. Therefore, using arginase 1 (Arg1) and transforming growth beta-1 (Tgfb1) as markers for M2 microglia activation, we found that compounds 1, 5, 12, 14, and 15 are the major M2-promoting constituents in SFI, which significantly upregulated Arg1 or Tgfb1 gene expression. Our results suggested that these compounds in SFI may promote M2 microglial activation and have potential uses in modulating microglial activation and alleviating neuroinflammation. [ABSTRACT FROM AUTHOR]

* Context.--The use of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serologic tests detects antibodies in the host, contributing to the identification of individuals who have been exposed to coronavirus disease 2019 (COVID-19). Objective.--To critically evaluate 2 commercially available SARS-CoV-2 serology tests. Design.--A total of 333 unique, nonduplicated serum samples obtained from COVID-19 patients (n = 170) and negative controls (n = 163) obtained before December 2019 were used in the study. Samples were tested on the Roche E411 and Abbott Architect i4000SR platforms, and results were correlated to reverse transcription polymerase chain reaction (PCR) results and clinical symptoms. Results.--There was a strong level of agreement in the qualitative results between both assays, with a Cohen j value of .840, P < .001. The specificity for both Roche and Abbott were excellent at 100%. Roche exhibited marginally better performance in the 21 days or more group with a sensitivity of 90.6% (95% CI, 75.8%-96.8%) versus an Abbott sensitivity of 84.4% (95% CI, 68.3%-93.1%), as well as in the 14- to 20-day group with a sensitivity of 85.7% (95% CI, 65.4%-95.0%) versus an Abbott sensitivity of 81.0% (95% CI, 60.0%-92.3%). Less than 14 days of symptoms groups exhibited poor sensitivity at less than 50% for both assays. The areas under curve (± standard error) for Roche (0.894 ± 0.025, P < .001) and Abbott (0.884 ± 0.026, P < .001) were very similar. Potential confounders for negative serologic results include antiretroviral medication use and pauci-symptomatic patients. Conclusions.--Specificities for high-throughput Roche and Abbott immunoassays are excellent, but users need to be cautious to interpret serologic test results after 14 days of symptoms to avoid false negatives. [ABSTRACT FROM AUTHOR]

[Objectives] To explore the moxibustion effect and mechanism of "Complementary Acupoints" on rheumatoid arthritis (RA). [Methods] A total of 32 Wistar rats were randomly divided into 4 group; normal control (K), model group (M group), " the Complementary Acupoints" Yanglingquan and Yinlingquan group (AB group), Shenshu and Zusanli group (CD group), with 8 rats in each group. Moxibustion was performed using refined moxa floss (2 mg/pc) on acupoints in both sides every other day, 5 pieces for each acupoint, and implemented for 10 times. Before and after the modeling and after the intervention, the left foot sole thermal pain threshold of each group was measured. After the intervention, the rats' left paws were examined by X-ray to detect the number of mast cells (MCs) and degranulation in the affected area of the foot. [Results] The thermal pain threshold of the model group was lower than that of the K group (P < 0.05). The number of MC in the affected area and the degranulation were increased. After the moxibustion intervention, the thermal pain threshold of the AB and CD groups was higher than that of the M group (P <0.05); the number of MCs and degranulation were decreased compared with M group, and the degree of reduction was better than that of CD group. The data of foot and claw showed that the foot and paw soft tissue swelling, bone and joint deformity and bone destruction were better in AB and CD groups were more relieved than that in M group. [Conclusions] The moxibustion of Complementary Acupoints can effectively intervene with RA of rats, and its mechanism may be closely related to the MC degranulation. [ABSTRACT FROM AUTHOR]

Lichong Shengsui Yin (LCSSY) is an effective and classic compound prescription of Traditional Chinese Medicines (TCMs) used for the treatment of ovarian cancer. To investigate its pharmacodynamic basis for treating ovarian cancer, the multi-dimensional spectrum-effect relationship was determined. Four compositions (I to IV) were obtained by extracting LCSSY successively with supercritical CO2 fluid extraction, 75% ethanol reflux extraction, and the water extraction-ethanol precipitation method. Nine samples for pharmacological evaluation and fingerprint analysis were prepared by changing the content of the four compositions. The specific proportions of the four compositions were designed according to a four-factor, three-level L9(34) orthogonal test. The pharmacological evaluation included in vitro tumor inhibition experiments and the survival extension rate in tumor-bearing nude mice. The fingerprint analyzed by chromatographic condition I (high-performance liquid chromatography-photodiode array detec tor, HPLC-PDA) identified 19 common peaks. High-performance liquid chromatography-photodiode array detector-Evaporative Light-scattering Detector (HPLC-PDA-ELSD )hyphenated techniques were used to compensate for the use of a single detector, and the fingerprint analyzed by chromatographic condition II identified 28 common peaks in PDA and 23 common peaks in ELSD. Furthermore, multiple statistical analyses were utilized to calculate the relationships between the peaks and the pharmacological results. The union of the regression and the correlation analysis results were the peaks of X5, X9, X11, X12, X16, X18, Y5, Y8, Y12, Y14, Y20, Z4, Z5, Z6, and Z8. The intersection of the regression and the correlation analysis results were the peaks of X11, X12, X16, X18, Y5, Y12, and Z5. The correlated peaks were assigned by comparing the fingerprints with the negative control samples and reference standard samples, and identifying the structure using high-performance liquid chromatography-mass spectrometry detector(HPLC-MS). The results suggested that the pharmacodynamic basis of LCSSY on anti-ovarian cancer activities were germacrone, furandiene, β-elemene, calycosin-7-glucoside, ononin, epimedin B, icariin, ginsenoside Rc, astragaloside, ginsenoside Rd, astragaloside II, and some unknown components. [ABSTRACT FROM AUTHOR]

Background: Our previous study showed that the NS1 protein of highly pathogenic avian influenza A virus H5N1 induced caspase-dependent apoptosis in human alveolar basal epithelial cells (A549), supporting its function as a proapoptotic factor during viral infection, but the mechanism is still unknown. Results: To characterize the mechanism of NS1-induced apoptosis, we used a two-hybrid system to isolate the potential NS1-interacting partners in A549 cells. We found that heat shock protein 90 (Hsp90) was able to interact with the NS1 proteins derived from both H5N1 and H3N2 viruses, which was verified by co-immunoprecitation assays. Significantly, the NS1 expression in the A549 cells dramatically weakened the interaction between Apaf-1 and Hsp90 but enhanced its interaction with cytochrome c (Cyt c), suggesting that the competitive binding of NS1 to Hsp90 might promote the Apaf-1 to associate with Cyt c and thus facilitate the activation of caspase 9 and caspase 3. Conclusions: The present results demonstrate that NS1 protein of Influenza A Virus interacts with heat hock protein Hsp90 and meidates the apoptosis induced by influenza A virus through the caspase cascade. [ABSTRACT FROM AUTHOR]

Pokemon, the POK erythroid myeloid ontogenic factor, not only regulates the expression of many genes, but also plays an important role in cell tumorigenesis. To investigate the molecular mechanism regulating expression of the Pokemon gene in humans, its 5′-upstream region was cloned and analyzed. Transient analysis revealed that the Pokemon promoter is constitutive. Deletion analysis and a DNA decoy assay indicated that the NEG-U and NEG-D elements were involved in negative regulation of the Pokemon promoter, whereas the POS-D element was mainly responsible for its strong activity. Electrophoretic mobility shift assays suggested that the NEG-U, NEG-D and POS-D elements were specifically bound by the nuclear extract from A549 cells in vitro. Mutation analysis demonstrated that cooperation of the NEG-U and NEG-D elements led to negative regulation of the Pokemon promoter. Moreover, the NEG-U and NEG-D elements needed to be an appropriate distance apart in the Pokemon promoter in order to cooperate. Taken together, our results elucidate the mechanism underlying the regulation of Pokemon gene transcription, and also define a novel regulatory sequence that may be used to decrease expression of the Pokemon gene in cancer gene therapy. [ABSTRACT FROM AUTHOR]

Random residual circular birefringence induced by a twist of single-mode fiber is the main cause of magnetic field Faraday phase error in depolarized interferometric fiber optic gyroscopes (D-IFOGs). Magnetic field Faraday phase error in D-IFOG includes both radial and axial phase errors; however, axial phase error has not been thoroughly researched and is usually neglected. A magnetic phase error model of D-IFOG along a radial direction is established by using a Jones matrix; then, the mathematical description of radial direction phase drift in D-IFOG is deduced according to the model. Based on a quadrupolar winding distribution structure in a fiber loop, a magnetic phase error model of D-IFOG along the axial direction is established, and phase drift in D-IFOG is deduced by using a coil expansion method. Theoretical analysis shows that nonreciprocal phase error in D-IFOG induced by magnetic field correlates with several factors, such as optical coherent length, optical polarization degree, etc. Then, measures to restrain the magnetic field phase error in D-IFOG are investigated, such as the new Lyot depolarizer, electromagnetic shielding, etc. Further, we experimentally present the performance of D-IFOG with the magnetic intensity of 150 Gs along axial and radial directions, respectively, and verify the effect of a new Lyot depolarizer on restraining magnetic phase error in D-IFOG. [ABSTRACT FROM AUTHOR]