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  1. Article ; Online: Preparation and Performance Evaluation of a Plugging Agent with an Interpenetrating Polymer Network

    Zengbao Wang / Yitian Liu / Weian Huang / Xiong Yang / Ziao Liu / Xushuo Zhang

    Gels, Vol 9, Iss 205, p

    2023  Volume 205

    Abstract: In view of the problems of polymer cross-linked elastic particle plugging agents commonly used in oilfields, including easy shear, poor temperature resistance, and weak plugging strength for large pores, the introduction of particles with certain ... ...

    Abstract In view of the problems of polymer cross-linked elastic particle plugging agents commonly used in oilfields, including easy shear, poor temperature resistance, and weak plugging strength for large pores, the introduction of particles with certain rigidity and network structure, and cross-linking with a polymer monomer can improve the structural stability, temperature resistance, and plugging effect, and the preparation method is simple and low-cost. An interpenetrating polymer network (IPN) gel was prepared in a stepwise manner. The conditions of IPN synthesis were optimized. The IPN gel micromorphology was analyzed by SEM and the viscoelasticity, temperature resistance, and plugging performance were also evaluated. The optimal polymerization conditions included a temperature of 60 °C, a monomer concentration of 10.0–15.0%, a cross-linker concentration of 1.0–2.0% of monomer content, and a first network concentration of 20%. The IPN showed good fusion degree with no phase separation, which was the prerequisite for the formation of high-strength IPN, whereas particle aggregates reduced the strength. The IPN had better cross-linking strength and structural stability, with a 20–70% increase in the elastic modulus and a 25% increase in temperature resistance. It showed better plugging ability and erosion resistance, with the plugging rate reaching 98.9%. The stability of the plugging pressure after erosion was 3.8 times that of a conventional PAM-gel plugging agent. The IPN plugging agent improved the structural stability, temperature resistance, and plugging effect of the plugging agent. This paper provides a new method for improving the performance of a plugging agent in an oilfield.
    Keywords interpenetrating polymer network ; elastic particle plugging agent ; viscoelasticity ; temperature resistance ; plugging performance ; Science ; Q ; Chemistry ; QD1-999 ; Inorganic chemistry ; QD146-197 ; General. Including alchemy ; QD1-65
    Subject code 669
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: CD226 maintains regulatory T cell phenotype stability and metabolism by the mTOR/Myc pathway under inflammatory conditions

    Jingchang Ma / Wei Hu / Yitian Liu / Chujun Duan / Dongliang Zhang / Yuling Wang / Kun Cheng / Lu Yang / Shuwen Wu / Boquan Jin / Yuan Zhang / Ran Zhuang

    Cell Reports, Vol 42, Iss 10, Pp 113306- (2023)

    2023  

    Abstract: Summary: Regulatory T (Treg) cells exhibit immunosuppressive phenotypes and particular metabolic patterns with certain degrees of plasticity. Previous studies of the effects of the co-stimulatory molecule CD226 on Treg cells are controversial. Here, we ... ...

    Abstract Summary: Regulatory T (Treg) cells exhibit immunosuppressive phenotypes and particular metabolic patterns with certain degrees of plasticity. Previous studies of the effects of the co-stimulatory molecule CD226 on Treg cells are controversial. Here, we show that CD226 primarily maintains the Treg cell stability and metabolism phenotype under inflammatory conditions. Conditional deletion of CD226 within Foxp3+ cells exacerbates symptoms in murine graft versus host disease models. Treg cell-specific deletion of CD226 increases the Treg cell percentage in immune organs but weakens their immunosuppressive function with a T helper 1-like phenotype conversion under inflammation. CD226-deficient Treg cells exhibit reduced oxidative phosphorylation and increased glycolysis rates, which are regulated by the adenosine 5′-monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/myelocytomatosis oncogene (Myc) pathway, and inhibition of Myc signaling restores the impaired functions of CD226-deficient Treg cells in an inflammatory disease model of colitis. This study reveals an Myc-mediated CD226 regulation of Treg cell phenotypic stability and metabolism, providing potential therapeutic strategies for targeted interventions of Treg cell-specific CD226 in inflammatory diseases.
    Keywords CP: Immunology ; Biology (General) ; QH301-705.5
    Subject code 570
    Language English
    Publishing date 2023-10-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Beneficial Effects of Sagacious Confucius’ Pillow Elixir on Cognitive Function in Senescence-Accelerated P8 Mice (SAMP8) via the NLRP3/Caspase-1 Pathway

    Zhitao Hou / Fengjin Li / Jing Chen / Yitian Liu / Changyuan He / Meng Wang / Tingting Mei / Yue Zhang / Liying Song / Xianming Shao

    Evidence-Based Complementary and Alternative Medicine, Vol

    2019  Volume 2019

    Abstract: Sagacious Confucius’ Pillow Elixir (SCPE) is a traditional Chinese medicine that is mainly used for cognitive impairment in aging; however, the underlying mechanisms remain unclear. Aging is one of the most important pathogenic factors leading to ... ...

    Abstract Sagacious Confucius’ Pillow Elixir (SCPE) is a traditional Chinese medicine that is mainly used for cognitive impairment in aging; however, the underlying mechanisms remain unclear. Aging is one of the most important pathogenic factors leading to inflammation and pyroptosis in the hippocampus, which may be a potential mechanism in elderly patients with cognitive impairment. Here, we examined whether SCPE could improve cognitive impairment in SAMP8 mice by reducing hippocampal inflammation and pyroptosis. Seven-month-old senescence-accelerated P8 mice (SAMP8) received SCPE (2.3 g/kg/day; 4.6 g/kg/day; 9.2 g/kg/day) for 28 days. Cognitive function and morphometric examinations were performed followed by water maze testing, hematoxylin-eosin staining, Congo red staining, toluidine blue staining, and TUNEL analysis of hippocampal CA1 and CA3 regions. Escape latency increased and times across platforms decreased in SAMP8 mice; however, both of them were normalized by SCPE after 28 days. Aging caused significant pyroptosis in hippocampal CA1 and CA3 regions, as evidenced by neuronal degeneration and necrosis, amyloid deposition, and decreased Nissl body amounts after cognitive impairment, which were greatly improved by SCPE. SCPE reduced serum IL-1β, IL-6, IL-18, and TNF-α levels and reduced hippocampal NLRP3, ASC, caspase-1, GSDM-D, IL-1β, IL-6, IL-18, and Aβ expression. Thus, SCPE exerts an antipyroptotic effect in aging, mainly by suppressing the NLRP3/caspase-1 signaling pathway.
    Keywords Other systems of medicine ; RZ201-999
    Language English
    Publishing date 2019-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: CD226 knockout alleviates high-fat diet induced obesity by suppressing proinflammatory macrophage phenotype

    Jingchang Ma / Wei Hu / Dongliang Zhang / Jiangang Xie / Chujun Duan / Yitian Liu / Yuling Wang / Xuexue Xu / Kun Cheng / Boquan Jin / Yuan Zhang / Ran Zhuang

    Journal of Translational Medicine, Vol 19, Iss 1, Pp 1-

    2021  Volume 16

    Abstract: Abstract Obesity is associated with chronic low-grade inflammation, contributing to an increasing prevalence of chronic metabolic diseases, such as insulin resistance, non-alcoholic fatty liver disease (NALFD), and steatohepatitis. Macrophages are the ... ...

    Abstract Abstract Obesity is associated with chronic low-grade inflammation, contributing to an increasing prevalence of chronic metabolic diseases, such as insulin resistance, non-alcoholic fatty liver disease (NALFD), and steatohepatitis. Macrophages are the predominant immune cells in adipose tissues. Adipose tissue macrophages (ATMs) would switch to pro-inflammatory M1 state during obesity, causing local and systemic inflammation. However, the regulatory mechanism of ATMs has not yet been well described within this process. Using a high-fat diet (HFD)–induced mouse obesity model, we found that the costimulatory molecule CD226 was highly expressed on ATMs and knockout (KO) of CD226 alleviated obesity caused by HFD. Loss of CD226 reduced the accumulation of ATMs and hindered macrophage M1 polarization, with lower serum proinflammatory cytokine levels. Furthermore, deficiency of CD226 on ATMs decreased the phosphorylation levels of VAV1, AKT, and FOXO1 and thereby upregulated PPAR-γ. Further administration of PPAR-γ inhibitor restored M1 phenotype in CD226KO ATMs. In summary, loss of CD226 alleviates the HFD-induced obesity and systemic inflammation through inhibition of the accumulation and M1 polarization of ATMs in which PPAR-γ-dependent signaling pathway is involved, suggesting that CD226 may be identified as a potential molecular target for the clinical treatment of obesity.
    Keywords CD226 ; HFD ; Obesity ; Macrophage ; Polarization ; Medicine ; R
    Language English
    Publishing date 2021-11-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Developmental Timing Determines the Protective Effect of Maternal Electroacupuncture on Perinatal Nicotine Exposure-Induced Offspring Lung Phenotype

    Jian Dai / Bo Ji / Guozhen Zhao / Yawen Lu / Yitian Liu / Qiujie Mou / Reiko Sakurai / Yana Xie / Qin Zhang / Shuang Xu / Virender K. Rehan

    BioMed Research International, Vol

    2020  Volume 2020

    Abstract: Introduction. Environmental exposure of the developing offspring to cigarette smoke or nicotine is an important predisposing factor for many chronic respiratory conditions, such as asthma, emphysema, pulmonary fibrosis, and so forth, in the exposed ... ...

    Abstract Introduction. Environmental exposure of the developing offspring to cigarette smoke or nicotine is an important predisposing factor for many chronic respiratory conditions, such as asthma, emphysema, pulmonary fibrosis, and so forth, in the exposed offspring. Studies showed that electroacupuncture (EA) applied to maternal “Zusanli” (ST36) acupoints during pregnancy and lactation protects against perinatal nicotine exposure- (PNE-) induced lung damage. However, the most effective time period, that is, prenatal vs. postnatal, to attain this effect has not been determined. Objective. To determine the most effective developmental timing of EA’s protective effect against PNE-induced lung phenotype in the exposed offspring. Methods. Pregnant rats were given (1) saline (“S” group); (2) nicotine (“N” group); (3) nicotine + EA, exclusively prenatally (“Pre-EA” group); (4) nicotine + EA, exclusively postnatally (“Post-EA,” group); and (5) nicotine + EA, administered both prenatally and postnatally (“Pre- and Post-EA” group). Nicotine was injected once daily (1 mg/kg, 100 μl) and EA was administered to bilateral ST36 acupoints once daily during the specified time-periods. At the end of the experimental periods, key hypothalamic pituitary adrenal (HPA) axis markers in pups and dams, and lung function, morphometry, and the central molecular markers of lung development in the offspring were determined. Results. After nicotine exposure, alveolar mean linear intercept (MLI) increased, but mean alveolar number (MAN) decreased and lung PPARγ level decreased, but glucocorticoid receptor (GR) and serum corticosterone (Cort) levels increased, in line with the known PNE-induced lung phenotype. In the nicotine exposed group, maternal hypothalamic corticotropin releasing hormone (CRH) level decreased, but pituitary adrenocorticotropic hormone (ACTH) and serum Cort levels increased. In the “Pre- and Post-EA” groups, PNE-induced alterations in lung morphometry, lung development markers, and HPA axis were blocked. In the “Pre-EA” group, ...
    Keywords Medicine ; R
    Subject code 630
    Language English
    Publishing date 2020-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Comparison of Protective Effects of Electroacupuncture at ST 36 and LU 5 on Pulmonary and Hypothalamic Pituitary Adrenal Axis Changes in Perinatal Nicotine-Exposed Rats

    Yawen Lu / Bo Ji / Guozhen Zhao / Jian Dai / Reiko Sakurai / Yitian Liu / Qiujie Mou / Yana Xie / Qin Zhang / Shuang Xu / Virender Kumar Rehan

    BioMed Research International, Vol

    2020  Volume 2020

    Abstract: Background. Maternal smoking and/or exposure to environmental tobacco smoke continue to be significant factors in fetal and childhood morbidity and are a serious public health issue worldwide. Nicotine passes through the placenta easily with minimal ... ...

    Abstract Background. Maternal smoking and/or exposure to environmental tobacco smoke continue to be significant factors in fetal and childhood morbidity and are a serious public health issue worldwide. Nicotine passes through the placenta easily with minimal biotransformation, entering fetal circulation, where it results in many harmful effects on the developing offspring, especially on the developing respiratory system. Objectives. Recently, in a rat model, electroacupuncture (EA) at maternal acupoints ST 36 has been shown to block perinatal nicotine-induced pulmonary damage; however, the underlying mechanism and the specificity of ST 36 acupoints for this effect are unknown. Here, we tested the hypothesis that compared with EA at ST 36, EA at LU 5 acupoints, which are on lung-specific meridian, will be equally or more effective in preventing perinatal nicotine-induced pulmonary changes. Methods. Twenty-four pregnant rat dams were randomly divided into 4 groups: saline (“S”), nicotine (“N”), nicotine + ST 36 (N + ST 36), and nicotine + LU 5 (N + LU 5) groups. Nicotine (1 mg/kg, subcutaneously) and EA (at ST 36 or LU 5 acupoints, bilaterally) were administered from embryonic day 6 to postnatal day 21 once daily. The “S” group was injected saline. As needed, using ELISA, western analysis, q-RT-PCR, lung histopathology, maternal and offspring hypothalamic pituitary adrenal axes, offspring key lung developmental markers, and lung morphometry were determined. Results. With nicotine exposure, alveolar count decreased, but mean linear intercept and septal thickness increased. It also led to a decrease in pulmonary function and PPARγ and an increase of β-catenin and glucocorticoid receptor expression in lung tissue and corticosterone in the serum of offspring rats. Electroacupuncture at ST 36 normalized all of these changes, whereas EA at LU 5 had no obvious effect. Conclusion. Electroacupuncture applied to ST 36 acupoints provided effective protection against perinatal nicotine-induced lung changes, whereas EA applied at LU 5 ...
    Keywords Medicine ; R
    Subject code 610
    Language English
    Publishing date 2020-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: InsR/FoxO1 signaling curtails hypothalamic POMC neuron number.

    Leona Plum / Hua V Lin / Kumiko S Aizawa / Yitian Liu / Domenico Accili

    PLoS ONE, Vol 7, Iss 2, p e

    2012  Volume 31487

    Abstract: Insulin receptor (InsR) signaling through transcription factor FoxO1 is important in the development of hypothalamic neuron feeding circuits, but knowledge about underlying mechanisms is limited. To investigate the role of InsR/FoxO1 signaling in the ... ...

    Abstract Insulin receptor (InsR) signaling through transcription factor FoxO1 is important in the development of hypothalamic neuron feeding circuits, but knowledge about underlying mechanisms is limited. To investigate the role of InsR/FoxO1 signaling in the development and maintenance of these circuits, we surveyed the pool of hypothalamic neurons expressing Pomc mRNA in different mouse models of impaired hypothalamic InsR signaling. InsR ablation in the entire hypothalamus did not affect Pomc-neuron number at birth, but resulted in a 25% increase, most notably in the middle arcuate nucleus region, in young adults. Selective restoration of InsR expression in POMC neurons in these mice partly reversed the abnormality, resulting in a 10% decrease compared to age-matched controls. To establish whether FoxO1 signaling plays a role in this process, we examined POMC neuron number in mice with POMC-specific deletion of FoxO1, and detected a 23% decrease in age-matched animals, consistent with a cell-autonomous role of InsR/FoxO1 signaling in regulating POMC neuron number, distinct from its established role to activate Pomc transcription. These changes in Pomc cells occurred in the absence of marked changes in humoral factors or hypothalamic NPY neurons.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2012-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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