Generally, P-wave is the wave of low-frequency and low-amplitude, and it could be affected by baseline drift, electromyography (EMG) interference and other noises easily. Not every heart beat contains the P-wave, and it is also a major problem to determine the P-wave exist or not in a heart beat. In order to solve the limitation of suiting the diverse morphological P-wave using wavelet-amplitude-transform algorithm and the limitation of selecting the pseudo-P-wave sample using the wavelet transform and neural network, we presented new P-wave detecting method based on wave-amplitude threshold and using the multi-feature as the input of neural networks. Firstly, we removed the noise of ECG through the wavelet transform, then determined the position of the candidate P-wave by calculating modulus maxima of the wavelet transform, and then determine the P-wave exist or not by wave-amplitude threshold method initially. Finally we determined whether the P-wave existed or not by the neural networks. The method is validated based on the QT database which is supplied with manual labels made by physicians. We compared the detection effect of ECG P-waves, which was obtained with the method developed in the study, with the algorithm of wavelet threshold value and the method based on "wavelet-amplitude-slope", and verified the feasibility of the proposed algorithm. The detected ECG signal, which is recorded in the hospital ECG division, was consistent with the doctor's labels. Furthermore, after detecting the 13 sets of ECG which were 15 min long, the detection rate for the correct P-wave is 99.911%.
Algorithms ; Databases, Factual ; Electromyography ; Heart Rate ; Humans ; Neural Networks (Computer) ; Wavelet Analysis

Objective To investigate the protective effct of Panax quinquefolium saponins from steams and leaves(PQS)on focal cerebral ischemia injury in rats and its mechanisms. Methods Wistar rats were randomly divided into sham operation group,model control group,nimodipine group and two PQS groups,in which PQS of 100 and 50 mg/kg was intragastrically administered. Focal cerebral ischemia model was established by middle cerebral artery occlusion (MCAO)in rats, via string ligation of artetia carotis interna. The content of malondicldehy de(MDA) was determined by thibabituric acid ( TBA ) test, the activity of lactate dehydrogenase ( LDH ), superoxide dismutase (SOD)and the content of lactic acid(LA) were detected by chemical colorimetry test in cerebral tissues. Results PQS( 100,50mg/kg)could significantly decrease the content of LA、MDA and increase the activity of LDH、SOD. Conclusion The protective mechanism of PQS on focal cerebral ischemia injury may be related to reduce acidosis, anti-free radical and resist oxidative damage.

This article introduces definitions of three special tests, namely, non-inferiority test (to verify that the efficacy of the experimental drug is clinically not inferior to that of the positive control drug), equivalence test (to verify that the efficacy of the experimental drug is equivalent to that of the control drug) and superiority test (to verify that the efficacy of the experimental drug is superior to that of the control drug), and methods of sample size estimation under the three different conditions. By specific examples, the article introduces formulas of sample size estimation for the three special tests, and their SAS realization in detail.

BACKGROUND: Isoflavone isolated from Trifolium pratense L. has been found to be able to effectively inhibit bone resorption, reduce bone turnover rate, improve osteocyte activity and bone mineral density by enhancing the effect of estrogen, which is helpful for the prevention and treatment of osteoporosis. OBJECTIVE: To investigate the effect of Trifolium pratense L. extracts on the bone resorption and differentiation of osteoclasts.METHODS: Rat bone marrow cells were extracted, isolated by lymphocyte separation and cultured for 5 hours; then, the non-adherent cells were selected followed by induced by 30 μg/L macrophage colony stimulating factor and 75 μg/L RANKL (control groups), or different concentrations of Trifolium pratense L. extracts (0.3, 0.6 and 1.2 g/L) to observe their effect on the osteoclast differentiation and bone resorption. The levels of osteoclast differentiation-associated proteins c-fos and NFATcl were determined by western blot assay. RESULTS AND CONCLUSION: Compared with the control group, different concentrations of Trifolium pratense L. extracts could suppress osteoclast differentiation and bone resorption to different degrees. Tartrate-resistant acid phosphatase staining showed that Trifolium pratense L. extracts could significantly reduce the number of osteoclasts. Western blot assay results suggest that Trifolium pratense L. extracts significantly inhibited the expression levels of c-fos and NFATcl. These results reveal that Trifolium pratense L. extracts can inhibit osteoclast differentiation and bone resorption.

Objective To explore the effects of gross saponins of Tribulus terrestris L.on inflammatory reaction and permeability of blood-brain barrier in rats following cerebral ischemia-reperfusion injury and their potential mechanisms. Methods Sixty SD rats were divided into sham operation group,model control group,gross saponins of Tribulus terrestris L.at low-dose (10 mg?kg-1 )and high-dose groups(30 mg?kg-1 ).Cerebral ischemia -reperfusion model was established with suture emboli method in middle cerebral artery of rats.Neural injury scores,the contents of Evans blue ( EB) and myeloperoxidase( MPO) activities in rat brain were measured 24 hours after the cerebral reperfusion post 2 h ischemia.Content of tumor necrosis factor-α (TNF-α) in rat brain was detected by ELISA; expression levels of matrix metalloproteinase-9(MMP-9) in rat brain was determined by Western blot. Results Compared to the model control group,the neurological deficit scores were significantly decreased(P<0.05),MPO activities and EB contents decreased(P< 0.05 or P< 0.01) in the treatment groups.The expression levels of TNF-α were significantly lower in the treatment groups(0.760±0.110) mg?g-1 and (0.670±0.073) mg?g-1 compared to (0.920±0.128) mg?g-1 in the model control group ( P< 0.05 or P< 0.01). The MMP-9 expression levels were (1.770± 0.181)% and(1.480±0.146)%,significantly lower than(2.200±0.186)% in the model control group(P<0.01). Conclusion Gross saponins of Tribulus terrestris L. exert neuroprotective effects on cerebral ischemia-reperfusion injury in rats through inhibiting the inflammatory reaction and decreasing the permeability of blood-brain barrier,which may be associated with the decrease of the TNF-α content and downregulation of the MMP-9 expression.

Objective: To analyze the epidemiological characteristics of latent syphilis in Yancheng City from 2016 to 2020, so as to provide insights into syphilis control. Methods: All reported cases with latent syphilis in Yancheng City from 2016 to 2020 was collected from the Communicable Disease Report System of China Disease Prevention and Control Information System, and the prevalence of latent syphilis was estimated and standardized by the seventh population census data in Yancheng City. The trends in the incidence of latent syphilis were evaluated using annual percent change (APC), and the temporal, regional and human distributions of latent syphilis patients were descriptively analyzed. In addition, the spatial clusters of latent syphilis incidence were identified using spatial autocorrelation analysis. Results: A total of 7 790 cases with latent syphilis were reported in Yancheng City from 2016 to 2020, and the standardized incidence of latent syphilis increased from 15.35/105 in 2016 to 28.70/105 in 2020 (APC=17.54%, t=5.357, P=0.013). Latent syphilis cases were reported in each month, and no obvious seasonable characteristics were seen. During the period from 2017 to 2020, the highest incidence of latent syphilis was seen in residents at ages of 70 to 79 years, with incidence rates of 41.71/105, 43.04/105, 75.79/105 and 72.94/105, respectively, and most cases were farmers (4 711 cases, 60.47%). The three highest incidence of latent syphilis was reported in Funing County (191.40/105), Tinghu District (137.13/105) and Yandu District (126.23/105). There was a positive spatial correlation of latent syphilis incidence in Yancheng City from 2016 to 2020 (Moran's I=0.23, Z=4.457, P=0.001), and two high-high clusters were identified in 14 townships (streets) of Funing County, Binhai County, Tinghu District, Sheyang County and Yandu District and 3 low-low clusters in 7 townships (streets) in Jianhu County, Tinghu District, Dongtai City and Sheyang County. Conclusions The incidence of latent syphilis appeared a tendency towards a rise, and there were remarkable spatial clusters identified in latent syphilis incidence in Yancheng City from 2016 to 2020. The elderly people and farmers are at high risk of latent syphilis.

Objective To evaluate the clinical application value of reflectance confocal microscopy(RCM) in the diagnosis of several common diseases manifesting as papules in children, including lichen nitidus, verruca planae, lichen striatus, milium, molluscum contagiosum and lichen pilaris. Methods A total of 579 children clinically characterized by papules were recruited into this study. RCM was used to observe lesions and perilesional normal skin. The RCM features of 6 diseases manifesting as papules were analyzed and compared. Results Based on RCM images, 236 patients were diagnosed with lichen nitidus, 70 with verruca planae, 123 with lichen striatus, 40 with milium, 53 with molluscum contagiosum and 57 with lichen pilaris. All the 6 diseases had typical RCM features. Concretely speaking, RCM images of lichen nitidus lesions showed infiltration of dense inflammatory cells and melanophages in enlarged dermal papillae. In RCM images of verruca planae lesions, cells in the granular and spinous layers were arranged in concentric circles, giving a rose cluster?like appearance. RCM images of lichen striatus lesions revealed focal swelling of stratum spinosum, absent or local liquifaction degeneration of basal cells, and clustering of a moderate number of inflammatory cells in the superficial dermis. In RCM images of milium lesions, well?circumscribed round or oval structures containing highly but nonuniformly refractive materials could be seen in the dermis. RCM images of molluscum contagiosum lesions showed intact cystoid structures containing highly refractive molluscum bodies. Lowly to moderately refractive cutin ? like materials were observed along with the dilation of hair follicle infundibula in RCM images of lichen pilaris lesions. In RCM images, the 6 diseases were distinguished mainly based on structural features(patterns and refractivity)of skin lesions shown by continuous vertical scanning. Conclusion RCM is of great value to the diagnosis of diseases manifesting as papules in children.

Objective:To explore the value of arterial spin labeling (ASL) in detecting epileptogenic zone (EZ) in children with drug-refractory epilepsy (DRE).Methods:From March 2018 to December 2019, 28 children with DRE were collected prospectively in Peking University First Hospital. Structural MRI, ASL sequence, and PET-CT were performed on 28 DRE children. All children underwent surgical treatment. Intraoperative electrocorticogram findings combined with postoperative MRI results were considered the gold standard for locating EZ. A total of 29 EZ were resected in 28 children. Based on the pathological results, the EZ was divided into focal cortical dysplasia (FCD) Ⅰb and Ⅱa group ( n=12), FCD Ⅱ b group ( n=11) and malformation of cortical dysplasia (MCD) group ( n=6). Structural MRI was observed for finding any abnormal changes that could induce epilepsy and was divided into the normal MRI group ( n=13) and the abnormal MRI group ( n=16). The spatial relationship between abnormal areas in the cerebral blood flow (CBF) map and PET images and the gold standard was observed, and the accurate detection rate of EZ was calculated. The region of interest (ROI) on CBF and PET images was drawn. ROIs were defined as EZ, EZ contralateral zone (EZCZ), EZ adjacent zone (EZAZ), EZAZ contralateral zone (EZAZCZ). The CBF and maximum standardized uptake value (SUV max) were measured, and the asymmetry index (AI) value of EZ and EZAZ of CBF and SUV max was calculated respectively. One-way ANOVA was used to compare the difference among 4 regions and 3 pathological types of CBF, SUV max, and AI. The independent sample t-test was used to compare the difference in AI between normal and abnormal MRI groups. Results:In CBF map, the EZ was accurately localized in 89.7% (26/29) of the lesions, in which 24 EZ had decreased perfusion, and 2 EZ had increased perfusion. Among the 24 EZ with decreased perfusion, the CBF of EZ, EZCZ, EZAZ, and EZAZCZ were significantly different( F=8.79, P<0.001). In PET-CT, the EZ was accurately localized in 93.1% (27/29) of the lesions, in which 25 EZ had decreased metabolism, and 2 EZ had increased metabolism. Among the 25 EZ with decreased metabolism, the SUV max of EZ, EZCZ, EZAZ, and EZAZCZ were significantly different ( F=6.40, P=0.001). The AI value of CBF and SUV max of EZ in the abnormal MRI group were larger than those of the normal MRI group, and the difference was statistically significant ( t=3.34, 3.09, P=0.002 , 0.004). There was no statistical difference in the AI values of CBF and SUV max among FCD Ⅰb and Ⅱa group, FCD Ⅱb group and MCD group ( F=2.05, 1.54, P=0.149, 0.234). Conclusions:ASL technology is accurate in detecting EZ. The changes in perfusion and metabolism of normal structural MRI EZ are greater than abnormal structural MRI EZ. There is no obvious difference in CBF and SUVmax changes in different pathological EZ.

Objective:To investigate the regulatory effects of mitofusin 1 (MFN1) on lipopolysaccharide (LPS)-induced Raw264.7 mouse macrophages pyroptosis and to provide reference for further study on the prevention of inflammation and fibrosis caused by macrophage dysfunction.Methods:Raw264.7 mouse macrophages were cultured in vitro and used to construct a model of LPS-induced pyroptosis. CCK-8 staining, PI staining, LDH release assay and Western blot were used to verify the Raw264.7 pyroptosis induced by LPS. MFN1 expression was detected by Western blot. DCFH-DA probe was used to detect the synthesis of total reactive oxygen species (ROS); Mito-SOX was used to detect mitochondrial ROS; JC-1 mitochondrial membrane potential was detected by fluorescence probe to reflect mitochondrial damage. Based on Ubibrowser database, it was predicted that MFN1 could bind to a variety of E3 ubiquitin ligases. Then, immunofluorescence and co-immunoprecipitation (CO-IP) were used to analyze MFN1 ubiquitination. An overexpression plasmid for MFN1 was constructed and transfected into Raw264.7 cells to detect the changes in pyroptosis and mitochondrial function. Results:LPS could induce the pyroptosis of Raw264.7 cells and mitochondrial dysfunction. MFN1 expression was decreased after LPS stimulation. Ubiquitinated MFN1 was detected by CO-IP. Ubiquitination inhibitor MG-132 inhibited LPS-induced expression of pyroptosis-related proteins including NLRP3, Pro-caspase-1, Caspase-1, IL-1β and IL-18 and improved mitochondrial function. MFN1 overexpression relieved the mitochondrial dysfunction and pyroptosis of Raw264.7 cells induced by LPS.Conclusions:The ubiquitination of MFN1 induced by LPS was involved in mitochondrial dysfunction and macrophage pyroptosis, suggesting that MFN1 was a potential target for the treatment of macrophage-induced inflammation and related diseases.