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991.
Dongwei Dou Xiaoyang Ren Mingli Han Xiaodong Xu Xin Ge Yuanting Gu Xinxing Wang Song Zhao 《Molecular oncology》2021,15(2):697
Circular RNAs (circRNAs) have been shown to modulate gene expression and participate in the development of multiple malignancies. The purpose of this study was to investigate the role of circ_0008039 in breast cancer (BC). The expression of circ_0008039, miR‐140‐3p, and spindle and kinetochore‐associated protein 2 (SKA2) was detected by qRT‐PCR. Cell viability, colony formation, migration, and invasion were evaluated using methylthiazolyldiphenyl‐tetrazolium bromide (MTT) assay, colony formation assay, and transwell assay, respectively. Glucose consumption and lactate production were measured using commercial kits. Protein levels of hexokinase II (HK2) and SKA2 were determined by western blot. The interaction between miR‐140‐3p and circ_0008039 or SKA2 was verified by dual‐luciferase reporter assay. Finally, a mouse xenograft model was established to investigate the roles of circ_0008039 in BC in vivo. We found that circ_0008039 and SKA2 were upregulated in BC tissues and cells, while miR‐140‐3p was downregulated. Knockdown of circ_0008039 suppressed BC cell proliferation, migration, invasion, and glycolysis. Moreover, miR‐140‐3p could bind to circ_0008039 and its inhibition reversed the inhibitory effect of circ_0008039 interference on proliferation, migration, invasion, and glycolysis in BC cells. SKA2 was verified as a direct target of miR‐140‐3p and its overexpression partially inhibited the suppressive effect of miR‐140‐3p restoration in BC cells. Additionally, circ_0008039 positively regulated SKA2 expression by sponging miR‐140‐3p. Consistently, silencing circ_0008039 restrained tumor growth via increasing miR‐140‐3p and decreasing SKA2. In conclusion, circ_0008039 downregulation suppressed BC cell proliferation, migration, invasion, and glycolysis partially through regulating the miR‐140‐3p/SKA2 axis, providing an important theoretical basis for treatment of BC.
Abbreviations
- ANOVA
- analysis of variance
- BC
- breast cancer
- circRNAs
- circular RNAs
- DMSO
- dimethyl sulfoxide
- ECAR
- extracellular acidification rate
- ECL
- enhanced chemiluminescence
- FBS
- fetal bovine serum
- HK2
- hexokinase II
- MEGM
- mammary epithelial growth medium
- miR‐140‐3p
- microRNA‐140‐3p
- MTT
- methylthiazolyldiphenyl‐tetrazolium bromide
- PBS
- phosphate‐buffered saline
- PRKAR1B
- protein kinase A regulatory subunit R1‐beta
- SD
- standard ± deviation
- SKA2
- spindle and kinetochore‐associated protein 2
992.
目的评估糖化血红蛋白(HbA1c)及C反应蛋白(CRP)测定在妊娠期糖尿病血糖控制及治疗中的指导意义。方法选取2016年7月—2017年2月于本院妇产科行产前检查的孕24~28周孕妇行空腹血糖(FBG)、75 g口服糖耐量试验(OGTT)、HbA1c及CRP检查,分为正常妊娠者(对照组),妊娠期糖耐量受损者(GIGT组),妊娠期糖尿病者(GDM组)各40例。对受试对象孕36~38周再次进行FBG、HbA1c及CRP复查,比较各项指标及转归。结果孕24~28周GIGT组及GDM组FBG、HbA1c及CRP指标均高于对照组(P<0.05);进行饮食控制及(或)胰岛素治疗后GIGT组及GDM组各指标均有不同程度下降,P<0.05,GIGT组部分孕妇可恢复至正常值。结论HbA1c检测快速简便,联合CRP有助于妊娠期糖尿病的临床检测及诊断,可用于孕期血糖控制的跟踪观察。 相似文献
993.
《Vaccine》2021,39(45):6601-6613
AKS-452 is a biologically-engineered vaccine comprising an Fc fusion protein of the SARS-CoV-2 viral spike protein receptor binding domain antigen (Ag) and human IgG1 Fc (SP/RBD-Fc) in clinical development for the induction and augmentation of neutralizing IgG titers against SARS-CoV-2 viral infection to address the COVID-19 pandemic. The Fc moiety is designed to enhance immunogenicity by increasing uptake via Fc-receptors (FcγR) on Ag-presenting cells (APCs) and prolonging exposure due to neonatal Fc receptor (FcRn) recycling. AKS-452 induced approximately 20-fold greater neutralizing IgG titers in mice relative to those induced by SP/RBD without the Fc moiety and induced comparable long-term neutralizing titers with a single dose vs. two doses. To further enhance immunogenicity, AKS-452 was evaluated in formulations containing a panel of adjuvants in which the water-in-oil adjuvant, Montanide™ ISA 720, enhanced neutralizing IgG titers by approximately 7-fold after one and two doses in mice, including the neutralization of live SARS-CoV-2 virus infection of VERO-E6 cells. Furthermore, ISA 720-adjuvanted AKS-452 was immunogenic in rabbits and non-human primates (NHPs) and protected from infection and clinical symptoms with live SARS-CoV-2 virus in NHPs (USA-WA1/2020 viral strain) and the K18 human ACE2-trangenic (K18-huACE2-Tg) mouse (South African B.1.351 viral variant). These preclinical studies support the initiation of Phase I clinical studies with adjuvanted AKS-452 with the expectation that this room-temperature stable, Fc-fusion subunit vaccine can be rapidly and inexpensively manufactured to provide billions of doses per year especially in regions where the cold-chain is difficult to maintain. 相似文献
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997.
目的探讨1.5T磁共振T2 mapping成像在腰椎间盘退行性变之中的诊断价值。方法选择2018年1月—2019年1月在本院行1.5T磁共振检查的50例腰背疼痛患者当做研究对象,所有患者均进行矢状位T1WI、T2WI、横断位T2WI、正中矢状位T2 mapping成像。以Pfirrmann标准作为依据,进行腰椎间盘分级,并对髓核、纤维环前缘和后缘T2值进行测量,分别对各级髓核及纤维环的前缘及后缘T2值进行对比,并对T2值、分级以及年龄之间的相关性进行分析,同时,选择15例患者时隔6个月进行第2次磁共振检查,对两次椎间盘T2值之间产生的差异进行对比。结果腰椎间盘各级髓核T2值中,Ⅳ级与Ⅴ级之间未见明显差异,无统计学意义,P>0.05,其余各级间均存在明显差异,有统计学意义,P<0.05;患者年龄与分级呈正相关,年龄与T2值呈负相关,T2值与分级呈负相关;15例患者前后两次检测中,椎间盘纤维环前缘、后缘、髓核T2值均不存在明显差异,无统计学意义,P>0.05。结论腰椎间盘退行性变采用1.5T磁共振T2 mapping成像进行检查,能够实现有效的定量评估,特别是髓核T2值可对Ⅰ~Ⅳ级椎间盘退行性变程度差异进行有效反映,值得应用。 相似文献
998.
Coronavirus disease 2019 has a wide range of clinical spectrum from asymptomatic infection to severe infection resulting in death within a short time. Currently, it is known that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) does not only cause a respiratory tract infection but a more complicated disease that can lead to multiple system involvement including the liver. Herein, we evaluate the epidemiology, the impact of liver injury/ dysfunction on disease prognosis, the pathophysiological mechanisms and management of liver injury. More than one-fourth of the patients have abnormal liver function tests, mostly a mild-to-moderate liver dysfunction. Liver injury is significantly associated with a poor clinical outcome. Direct cytotoxic effect of SARS-CoV-2, the immune response (“cytokine storm”), the complications related to the disease, and drugs used in the treatments are the pathophysiological mechanisms responsible for liver injury. However, the exact mechanism is not yet clearly explained. The binding of SARS-CoV-2 to the angiotensin-converting enzyme 2 receptors and entering the hepatocyte and cholangiocytes can cause cytotoxic effects on the liver. Excessive immune response has an important role in disease progression and causes acute respiratory distress syndrome and multi-organ failures accompanied by liver injury. Treatment drugs, particularly lopinavir/ritonavir, remdesivir and antibiotics are a frequent reason for liver injury. The possible reasons should be meticulously investigated and resolved. 相似文献
999.
It has been well recognized that prolactin (PRL), a pleiotropic hormone, has many functions in the brain, such as maternal behavior, neurogenesis, and neuronal plasticity, among others. Recently, it has been reported to have a significant role in neuroprotection against excitotoxicity. Glutamate excitotoxicity is a common alteration in many neurological and neurodegenerative diseases, leading to neuronal death. In this sense, several efforts have been made to decrease the progression of these pathologies. Despite various reports of PRL’s neuroprotective effect against excitotoxicity, the signaling pathways that underlie this mechanism remain unclear. This review aims to describe the most recent and relevant studies on the molecular signaling pathways, particularly, PI3K/AKT, NF-κB, and JAK2/STAT5, which are currently under investigation and might be implicated in the molecular mechanisms that explain the PRL effects against excitotoxicity and neuroprotection. Remarkable neuroprotective effects of PRL might be useful in the treatment of some neurological diseases. 相似文献
1000.
Norio Itokawa Masanori Atsukawa Akihito Tsubota Noritomo Shimada Hidenori Toyoda Koichi Takaguchi Atsushi Hiraoka Tomonori Senoh Mai Koeda Yuji Yoshida Tomomi Okubo Taeang Arai Korenobu Hayama Ai Nakagawa-Iwashita Chisa Kondo Katsuhiko Iwakiri 《Internal medicine (Tokyo, Japan)》2021,60(4):507
Objective Pegylated-interferon monotherapy is the standard treatment for patients with chronic hepatitis B; however, the factors associated with its therapeutic effects remain unclear. Methods Patients with chronic hepatitis B were treated with pegylated interferon α-2a for 48 weeks. We evaluated the kinetics of hepatitis B surface antigen (HBsAg) during treatment and follow-up periods and the factors associated with an HBsAg response (defined as a change in HBsAg of ≥-1 log IU/mL from baseline). Results The study population comprised 50 patients. The median baseline levels of hepatitis B virus DNA and HBsAg were 5.00 and 3.40 log IU/mL. The median values of HBsAg reduction from baseline were -0.44 (n=48), -0.41 (n=40), and -0.68 (n=11) log IU/mL at the end of treatment and at 48 and 144 weeks post-treatment, respectively. The rates of HBsAg response were 24.0% and 22.5% at the end of treatment and at 48 weeks post-treatment, respectively. A multivariate analysis identified HBsAg <3.00 log IU/mL as an independent baseline factor contributing to the HBsAg response at the end of treatment and 48 weeks post-treatment (p=1.07×10-2 and 4.42×10-2, respectively). There were significant differences in the reduction of the HBsAg levels at 12 weeks of treatment and in the incidence of serum ALT increase during treatment between patients with and without an HBsAg response. Conclusion These findings suggest that the baseline HBsAg level, HBsAg kinetics at 12 weeks of treatment, and ALT increase during treatment are important factors contributing to the HBsAg response in pegylated interferon α-2a monotherapy for patients with chronic hepatitis B. 相似文献