The tumor suppressor programmed cell death 4 (PDCD4) is downregulated in various tumor tissues indicating poor prognosis. PDCD4 is the first protein found to resist tumor transformation, invasion, and metastasis by inhibiting translation. The functions of PDCD4 dependent on its structures are affected by extracellular signals.
View Article and Find Full Text PDFThe global outbreak of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), as of 8 May 2021, has surpassed 150 700 000 infections and 3 279 000 deaths worldwide. Evidence indicates that SARS-CoV-2 RNA can be detected on particulate matter (PM), and COVID-19 cases are correlated with levels of air pollutants. However, the mechanisms of PM involvement in the spread of SARS-CoV-2 remain poorly understood.
View Article and Find Full Text PDFThis paper aimed to study the effect nitrogen supplying on biomass accumulation and root respiration dynamic change of Glycyrrhiza uralensis and reveal the metabolic pathway of root respiration impact the biomass accumulating of G. uralensis. Six groups of one-year-old G.
View Article and Find Full Text PDFOct1 (Pou2f1) is a transcription factor of the POU-homeodomain family that is unique in being ubiquitously expressed in both embryonic and adult mouse tissues. Although its expression profile suggests a crucial role in multiple regions of the developing organism, the only essential function demonstrated so far has been the regulation of cellular response to oxidative and metabolic stress. Here, we describe a loss-of-function mouse model for Oct1 that causes early embryonic lethality, with Oct1-null embryos failing to develop beyond the early streak stage.
View Article and Find Full Text PDFZhongguo Yi Liao Qi Xie Za Zhi
March 2009
In this paper, one kind of suction apparatus is introduced, which could use manual, foot control and control combination. The design mentality, realization method, installation constitution and application method are also described. It is suitable to the nonmotile source condition and transportation situation, adapting easily to environment, and getting into favour with the medical staff and field first-aid personnel.
View Article and Find Full Text PDFObjective: To study the ECG and electrophysiological characteristic of idiopathic ventricular tachycardia (VT) and premature ventricular contraction (PVC) originating from ventricular outflow tract and assess the clinical effect of radiofrequency catheter ablation (RFCA) for treatment.
Methods: 105 patients aged from 12 to 73 years old were treated with RFCA. Activation mapping, pace mapping and non-contact mapping system of Ensite 3000 were used during the procedure.
A series of experiments were carried out to develop a new method to reduce pig polyspermic fertilization and produce more normal embryos, in vitro. Experiment 1 determined the effect of methyl-beta-cyclodextrin (MCD) treatment during cryopreservation on sperm acrosome reaction and sperm fertilization. Compared to the non-MCD-treated control, MCD treatment increased the percentage of acrosome-reacted spermatozoa at thawing and 2h after incubation in fertilization medium (P<0.
View Article and Find Full Text PDFThe present experiments were conducted to optimize in vitro fertilization conditions for zona pellucida-free (ZP-free) oocytes and their subsequent development. The results demonstrated that: (1) maximal fertilization efficiency was achieved at 200 spermatozoa per ZP-free oocyte. At this sperm dose, there were no significant differences in penetration rates and polyspermy rates from controls (zona-intact oocytes with 1000 spermatozoa/oocyte), indicating that ZPs of in vitro matured pig oocytes failed to block polyspermy during in vitro fertilization.
View Article and Find Full Text PDFPolyspermy is one of the most commonly observed abnormal types of fertilization in mammalian oocytes. In vitro fertilization (IVF) provides approaches to study the mechanisms by which oocytes block polyspermic fertilization. Accumulated data indicate that oocyte, sperm and insemination conditions are all related to the occurrence of polyspermic fertilization.
View Article and Find Full Text PDFButyrolactone I specifically inhibits M-phase promoting factor activation and prevents the resumption of meiosis. These experiments were conducted to examine effects of butyrolactone I on pig oocytes in a serum-free maturation system. The first experiment was conducted to determine the effect of butyrolactone I (0-100 microM) on nuclear maturation.
View Article and Find Full Text PDFWe used okadaic acid (OA), a potent inhibitor of protein phosphatases 1 and 2A, to study the regulatory effects of protein phosphatases on mitogen-activated protein (MAP) kinase phosphorylation, morphological changes in the nucleus, and microtubule assembly during pig oocyte maturation and fertilization in vitro. When germinal vesicle (GV) stage oocytes were exposed to OA, MAP kinase phosphorylation was greatly accelerated, being fully activated at 10 min. However, MAP kinase was dephosphorylated by long-term (>20 h) exposure to OA.
View Article and Find Full Text PDFSheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao (Shanghai)
January 1996
We have studied the fluorescence red-edge-excitation effects of human serum albumin. Our results indicate that the red-edge-excitation effects of human serum albumin depend on the pH, temperature and concentration of the denaturant. The different red-edge-excitation effects are produced by a redistribution of the energy levels both in the ground and the exited states of the chromphore aroused by changes of external conditions.
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