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      • KCI등재

        Gut Microbiota Dysbiosis Correlates With Long COVID-19 at One-Year After Discharge

        Zhang Dongmei,Zhou Yaya,Ma Yanling,Chen Ping,Tang Jian,Yang Bohan,Li Hui,Liang Mengyuan,Xue YuE,Liu Yao,Zhang Jianchu,Wang Xiaorong 대한의학회 2023 Journal of Korean medical science Vol.38 No.15

        Background: Long coronavirus disease 2019 (COVID-19) in recovered patients (RPs) is gradually recognized by more people. However, how long it will last and the underlining mechanism remains unclear. Methods: We conducted a prospective follow-up study to evaluate the long-term symptoms and clinical indices of RPs at one-year after discharge from Union Hospital, Wuhan, China between December 2020 to May 2021. We also performed the 16S rRNA sequencing of stool samples from RPs and healthy controls (HCs) and analyzed the correlation between the gut microbiota and long COVID-19. Results: In total, 187 RPs were enrolled, among them, 84 (44.9%) RPs reported long COVID-19 symptoms at one-year after discharge. The most common long-term symptoms were cardiopulmonary symptoms, including chest tightness after activity (39/187, 20.9%), palpitations on exercise (27/187, 14.4%), sputum (21/187, 11.2%), cough (15/187, 8.0%) and chest pain (13/187, 7.0%), followed by systemic symptoms including fatigue (34/187, 18.2%) and myalgia (20/187, 10.7%), and digestive symptoms including constipation (14/187, 7.5%), anorexia (13/187, 7.0%), and diarrhea (8/187, 4.3%). Sixty-six (35.9%) RPs presented either anxiety or depression (42/187 [22.8%] and 53/187 [28.8%] respectively), and the proportion of anxiety or depression in the long symptomatic group was significantly higher than that in the asymptomatic group (41/187 [50.6%] vs. 25/187 [24.3%]). Compared with the asymptomatic group, scores of all nine 36-Item Short Form General Health Survey domains were lower in the symptomatic group (all P < 0.05). One hundred thirty RPs and 32 HCs (non-severe acute respiratory syndrome coronavirus 2 infected subjects) performed fecal sample sequencing. Compared with HCs, symptomatic RPs had obvious gut microbiota dysbiosis including significantly reduced bacterial diversities and lower relative abundance of short-chain fatty acids (SCFAs)-producing salutary symbionts such as Eubacterium_hallii_group, Subdoligranulum, Ruminococcus, Dorea, Coprococcus, and Eubacterium_ventriosum_group. Meanwhile, the relative abundance of Eubacterium_hallii_group, Subdoligranulum, and Ruminococcus showed decreasing tendencies between HCs, the asymptomatic group, and the symptomatic group. Conclusion: This study demonstrated the presence of long COVID-19 which correlates with gut microbiota dysbiosis in RPs at one-year after discharge, indicating gut microbiota may play an important role in long COVID-19.

      • KCI등재

        Retrieving Phase from Single Interferogram with Spatial Carrier Frequency by Using Morlet Wavelet

        Hongxin Zhang,Mengyuan Cui 한국광학회 2023 Current Optics and Photonics Vol.7 No.5

        The Morlet wavelet transform method is proposed to analyze a single interferogram with spatial carrier frequency that is captured by an optical interferometer. The method can retain low frequency components that contain the phase information of a measured optical surface, and remove high frequency disturbances by wavelet decomposition and reconstruction. The key to retrieving the phases from the low-frequency wavelet components is to extract wavelet ridges by calculating the maximum value of the wavelet transform amplitude. Afterwards, the wrapped phases can be accurately solved by multiple iterative calculations on wavelet ridges. Finally, we can reconstruct the wavefront of the measured optical element by applying two-dimensional discrete cosine transform to those wrapped phases. Morlet wavelet transform does not need to remove the spatial carrier frequency components manually in the processing of interferogram analysis, but the step is necessary in the Fourier transform algorithm. So, the Morlet wavelet simplifies the process of the analysis of interference fringe patterns compared to Fourier transform. Consequently, wavelet transform is more suitable for automated programming analysis of interference fringes and avoiding the introduction of additional errors compared with Fourier transform.

      • KCI등재

        Multi‑condition dynamic model control strategy of the direct drive motor of electric vehicles based on PIO–LightGBM algorithm

        Fang Xie,Wenyu Zhang,Mengyuan Shen,Jinqiang Zhang 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.3

        Permanent magnet synchronous motor (PMSM) is widely used in new energy vehicles. At present, to make electric vehicles have a wider speed range, the motor can reach the rated speed above through the field-weakening control. However, when the traditional field-weakening control strategy is above the rated speed, the dynamic response ability of the vehicle declines. Problems such as torque oscillation and current jump occur. To solve these problems, based on a pigeon-inspired optimization (PIO) algorithm and optimized light gradient boosting machine (LightGBM), the dynamic response capability of the permanent magnet synchronous motor is improved. The robust adaptability of the control system to disturbances and parameter changes is also further improved. By collecting experimental data, the importance of relevant variables is analyzed, and the variable with the largest weight is selected as the input of the model. PIO is used to optimize LightGBM, and the loss function is optimized. Finally, the regression model is established. Simulation and experimental results show that the method is effective.

      • SCIESCOPUSKCI등재

        Neuroprotection of Dexmedetomidine against Cerebral Ischemia-Reperfusion Injury in Rats: Involved in Inhibition of NF-κB and Inflammation Response

        Wang, Lijun,Liu, Haiyan,Zhang, Ligong,Wang, Gongming,Zhang, Mengyuan,Yu, Yonghui The Korean Society of Applied Pharmacology 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.4

        Dexmedetomidine is an ${\alpha}2$-adrenergic receptor agonist that exhibits a protective effect on ischemia-reperfusion injury of the heart, kidney, and other organs. In the present study, we examined the neuroprotective action and potential mechanisms of dexmedetomidine against ischemia-reperfusion induced cerebral injury. Transient focal cerebral ischemia-reperfusion injury was induced in Sprague-Dawley rats by middle cerebral artery occlusion. After the ischemic insult, animals then received intravenous dexmedetomidine of $1{\mu}g/kg$ load dose, followed by $0.05{\mu}g/kg/min$ infusion for 2 h. After 24 h of reperfusion, neurological function, brain edema, and the morphology of the hippocampal CA1 region were evaluated. The levels and mRNA expressions of interleukin-$1{\beta}$, interleukin-6 and tumor nevrosis factor-${\alpha}$ as well as the protein expression of inducible nitric oxide synthase, cyclooxygenase-2, nuclear factor-${\kappa}Bp65$, inhibitor of ${\kappa}B{\alpha}$ and phosphorylated of ${\kappa}B{\alpha}$ in hippocampus were assessed. We found that dexmedetomidine reduced focal cerebral ischemia-reperfusion injury in rats by inhibiting the expression and release of inflammatory cytokines and mediators. Inhibition of the nuclear factor-${\kappa}B$ pathway may be a mechanism underlying the neuroprotective action of dexmedetomidine against focal cerebral I/R injury.

      • KCI우수등재

        Intestinal segment and vitamin D3 concentration affect gene expression levels of calcium and phosphorus transporters in broiler chickens

        Jincheng Han,Lihua Wu,Xianliang Lv,Mengyuan Liu,Yan Zhang,Lei He,Junfang Hao,Li Xi,Hongxia Qu,Chuanxin Shi,Zhiqiang Li,Zhixiang Wang,Fei Tang,Yingying Qiao 한국축산학회 2023 한국축산학회지 Vol.65 No.2

        Two experiments were conducted in this research. Experiment 1 investigated the spatial expression characteristics of calcium (Ca) and phosphorus (P) transporters in the duodenum, jejunum, and ileum of 21-day-old broilers provided with adequate nutrient feed. Experiment 2 evaluated the effects of dietary vitamin D3 (VD3) concentration (0, 125, 250, 500, 1,000, and 2,000 IU/kg) on growth performance, bone development, and gene expression levels of intestinal Ca and P transporters in 1–21-day-old broilers provided with the negative control diet without supplemental VD3. Results in experiment 1 showed that the mRNA levels of calcium- binding protein 28-kDa (CaBP-D28k), sodium-calcium exchanger 1 (NCX1), plasma membrane calcium ATPase 1b (PMCA1b), and IIb sodium-phosphate cotransporter (NaPi-IIb) were the highest in the broiler duodenum. By contrast, the mRNA levels of inorganic phosphate transporter 1 (PiT-1) and 2 (PiT-2) were the highest in the ileum. Results in experiment 2 showed that adding 125 IU/kg VD3 increased body weight gain (BWG), feed intake (FI), bone weight, and percentage and weight of Ca and P in the tibia and femur of 1–21-day-old broilers compared with the negative control diet (p < 0.05). The rise in dietary VD3 levels from 125 to 1,000 IU/kg further increased the BWG, FI, and weights of the bone, ash, Ca, and P (p < 0.05). No difference in growth rate and leg bone quality was noted in the broilers provided with 1,000 and 2,000 IU/kg VD3 (p > 0.05). Supplementation with 125–2,000 IU/kg VD3 increased the mRNA abundances of intestinal Ca and P transporters to varying degrees. The mRNA level of CaBP-D28k increased by 536, 1,161, and 28 folds in the duodenum, jejunum, and ileum, respectively, after adding 1,000 IU/kg VD3. The mRNA levels of other Ca and P transporters (PMCA1b, NCX1, NaPi-IIb, PiT-1, and PiT-2) increased by 0.57–1.74 folds by adding 1,000–2,000 IU/kg VD3. These data suggest that intestinal Ca and P transporters are mainly expressed in the duodenum of broilers. Moreover, the addition of VD3 stimulates the two mineral transporter transcription in broiler intestines.

      • KCI등재

        Dynamics of fungal community during silage fermentation of elephant grass (Pennisetum purpureum) produced in northern Vietnam

        Viet Ha Vu,Xiyang Li,Mengyuan Wang,Rongmei Liu,Guojian Zhang,Wei Liu,Baixue Xia,Qun Sun 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.7

        Objective: This study aimed to gain deeper insights into the dynamic changes in spoilage fungi populations during fermentation and the influence of traditional additives on silage quality. Methods: Elephant grass (Pennisetum purpureum) was prepared without any additive (control), and with the addition of 0.5% salt, and 0.5% salt–0.2% sugar mixture. The fungal community was then determined using a classic culturing method and high-throughput sequencing at 0, 5, 15, and 60 days after ensiling. Results: The results showed that the fungal community of elephant grass silage varied significantly between the natural fermentation without any additive and the two additive groups. The diversity and relative abundance of spoilage molds in the control group were much higher than those in the two treatment groups (p<0.05). Three species of yeasts (Candida sp., Pichia sp., Trichosporon sp.) and four spoilage molds (Fusarium sp., Aspergillus sp., Muco sp. and Penicillin sp.) were the predominant fungi in elephant grass during natural fermentation from 0 to 60 days, which were found to be significantly decreased in salt and sugar additive groups (p<0.05). Meanwhile, the diversity and relative abundance of undesirable molds in the 0.5%-salt additive group were the lowest among all groups. Conclusion: Adding salt and sugar, particularly 0.5% salt, is a promising effective approach to reduce the amount of undesirable fungi thus, improving the silage quality of elephant grass in northern Vietnam.

      • KCI등재

        Neuroprotection of Dexmedetomidine against Cerebral Ischemia-Reperfusion Injury in Rats: Involved in Inhibition of NF-κB and Inflammation Response

        ( Lijun Wang ),( Haiyan Liu ),( Ligong Zhang ),( Gongming Wang ),( Mengyuan Zhang ),( Yonghui Yu ) 한국응용약물학회 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.4

        Dexmedetomidine is an α2-adrenergic receptor agonist that exhibits a protective effect on ischemia-reperfusion injury of the heart, kidney, and other organs. In the present study, we examined the neuroprotective action and potential mechanisms of dexmedetomidine against ischemia-reperfusion induced cerebral injury. Transient focal cerebral ischemia-reperfusion injury was induced in Sprague-Dawley rats by middle cerebral artery occlusion. After the ischemic insult, animals then received intravenous dexmedetomidine of 1 mg/kg load dose, followed by 0.05 mg/kg/min infusion for 2 h. After 24 h of reperfusion, neurological function, brain edema, and the morphology of the hippocampal CA1 region were evaluated. The levels and mRNA expressions of interleukin-1b, interleukin-6 and tumor nevrosis factor-α as well as the protein expression of inducible nitric oxide synthase, cyclooxygenase-2, nuclear factor-κBp65, inhibitor of κBα and phosphorylated of κBα in hippocampus were assessed. We found that dexmedetomidine reduced focal cerebral ischemia-reperfusion injury in rats by inhibiting the expression and release of inflammatory cytokines and mediators. Inhibition of the nuclear factor-κB pathway may be a mechanism underlying the neuroprotective action of dexmedetomidine against focal cerebral I/R injury.

      • SCIESCOPUSKCI등재

        Age quadratically affects intestinal calcium and phosphorus transporter gene expression in broiler chickens

        Lv, Xianliang,Hao, Junfang,Wu, Lihua,Liu, Mengyuan,He, Lei,Qiao, Yingying,Cui, Yanyan,Wang, Guan,Zhang, Chunmei,Qu, Hongxia,Han, Jincheng Asian Australasian Association of Animal Productio 2022 Animal Bioscience Vol.35 No.12

        Objective: This research aimed to evaluate the effects of age on growth, tibia development, and intestinal calcium (Ca) and phosphorus (P) transporter gene expressions in broiler chickens. Methods: A total of 224 male Arbor Acres broilers were fed with nutrient-adequate diets and reared in eight cages (28 broilers per cage). Eight broilers (one broiler per cage) were selected and killed at 5, 10, 15, 20, 25, 30, 35, and 40 days of age, respectively. Results: Body weight continuously increased with age of broiler chickens from 5 to 40 days. The bone weight, ash weight, diameter, and length of the tibia also increased with broiler age. By contrast, the tibia ash, Ca, and P percentages quadratically changed with age (p<0.001), and the highest values of mineral contents were observed at 20, 25, and 25 days of age, respectively. The mRNA abundances of calcium-binding protein 28-kDa (CaBP-D28k), sodium-calcium exchanger 1 (NCX1), and plasma membrane ATPase 1b (PMCA1b) increased from 5 to 25 days and then decreased up to 40 days. Similar results were noted in the mRNA abundances of IIb sodium-phosphate cotransporter (NaPi-IIb), inorganic phosphate transporter 1 (PiT-1), inorganic phosphate transporter 2 (PiT-2), nuclear vitamin D receptor (nVDR), and membrane vitamin D receptor (mVDR). The mRNA abundances of Ca and P transporters and VDRs were the highest at 25 days of age. Conclusion: These data indicate that age quadratically affects intestinal Ca and P transporter gene expression and mineral absorption capacity in broiler chickens.

      • KCI등재

        Numerical study of hydrodynamic and thermodynamic characteristics of a heat exchanger muffler

        Meng Yuan,Pingjian Ming,Wenping Zhang 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.11

        The hydrodynamic and thermodynamic characteristics of a heat exchanger muffler (HEM), which can reduce the size of a marine engine exhaust system with waste heat recovery, were investigated using a numerical simulation method that combines the porous media model and the dual cell heat exchanger model. The effect of the thermal conductivity and dynamic viscosity of the exhaust gas on the heat transfer and pressure loss of the equipment was studied. The relationship between the heat transfer and the pressure drop of the equipment for various mass flow rates of the exhaust gas was investigated. It is shown that heat transfer conditions of the HEM could be enhanced by increasing the thermal conductivity or dynamic viscosity of the exhaust gas. To further improve the performance of the HEM, a design modification for optimizing the structure of the guide blade was proposed and numerically validated.

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