The possibility that exposure to general anesthetics during early life results in long-term impairment of neural function attracted considerable interest over the past decade. Extensive laboratory ...data suggest that administration of these drugs during critical stages of central nervous system development can lead to cell death, impaired neurogenesis, and synaptic growth as well as cognitive deficits. These observations are corroborated by several recent human epidemiological studies arguing that such cognitive impairment might also occur in humans. Despite the potential public health importance of this issue, several important questions remain open. Amongst them, how the duration of anesthesia exposure impact on outcome is as yet not fully elucidated. To gain insight into this question, here we focused on the short- and long-term impact of a 30-min-long exposure to clinically relevant concentrations of sevoflurane in rat pups at 2 functionally distinct stages of the brain growth spurt. We show that this treatment paradigm induced developmental stage-dependent and brain region-specific acute but not lasting changes in dendritic spine densities. Electrophysiological recordings in hippocampal brain slices from adult animals exposed to anesthesia in the early postnatal period revealed larger paired-pulse facilitation but no changes in the long-term potentiation paradigm when compared with nonanesthetized controls. 5-bromo-2-deoxyuridine pulse and pulse-chase experiments demonstrated that neither proliferation nor differentiation and survival of hippocampal progenitors were affected by sevoflurane exposure. In addition, behavioral testing of short- and long-term memory showed no differences between control and sevoflurane-exposed animals. Overall, these results suggest that brief sevoflurane exposure during critical periods of early postnatal development, although it does not seem to exert major long-term effects on brain circuitry development, can induce subtle changes in synaptic plasticity and spine density of which the physiological significance remains to be determined.
•Extended component assignment problems (CAPs) under uncertainties are proposed.•Extended LK heuristics are proposed to solve CAPs under uncertainties.•Interval-valued Birnbaum importance measures ...are proposed.•Systems under uncertainties are modeled by evidential network and belief functions.
The optimization of the consecutive-k-out-of-n system is to find the optimal assignment of components that maximizes the system reliability. Many efforts have been devoted to the component assignment problems (CAPs) for such systems, however, uncertainties about the reliability data of components and the system structure have never been deeply studied in CAPs. Due to the insufficiency of relative data and system complexities, uncertainties inevitably exist in many real engineering problems. This paper extends the LK heuristic using a non-probabilistic graphical model called evidential network, and interval-valued importance measures to perform the optimization of linear consecutive-k-out-of-n: F systems under parametric uncertainty (related to the reliability data of components) and model uncertainty (related to the system structure). The extended LK heuristics are applied to an oil pipeline system and an illustrative example system to show their feasibility and applicability. The originality of this work lies in the extension of the CAPs to consider different kinds of uncertainties and the proposition of heuristics to find the near optimal assignment of components under uncertainties according to the preference level of the decision maker.
Hepatitis C virus (HCV) infection is one of the leading causes of death and morbidity associated with liver disease. Risk factors identified for the transmission of HCV include contaminated blood ...products, intravenous drug use, body piercing, an infected mother at birth, sexual activity, and dental therapy, among others. However, the exact diversity of the HCV genotype and genetic variation among patients with low-risk factors is still unknown. In this study, we briefly described and analysed the genotype distribution and genetic variation of HCV infections with low-risk factors using molecular biology techniques. The results suggested that genotype 1b was predominant, followed by genotypes 2a and 1a. Genetic variations in the 5′ UTR sequences of HCV were identified, including point mutations, deletions, and insertions. The frequency of genetic variations in 1b was higher than in 2a. This study provides considerable value for the prevention and treatment of liver disease caused by HCV among patients with low-risk factors and for the development of HCV diagnostic reagents and vaccines.
It is observed that ramie (
Boehmeria nivea), an economic fiber crop, can establish and colonize metal-contaminated sites in China. Metal tolerance and accumulation by ramie originating from 13 ...metal-contaminated and 4 “clean” sites in China were compared under field and hydroponic conditions. All selected populations and germplasms displayed good growth performance under diverse metal-contaminated habitats; while growth responses, metal accumulation and tolerance were similar among the 8 populations and 2 germplasms when exposed to solutions containing elevated As, Cd, Pb, or Zn in the laboratory. These revealed that ramie possesses a certain degree of constitutional metal tolerance. To our knowledge, this is the first report of constitutional metal tolerance possessed by a fiber crop. Ramie can be considered as a good candidate for both fiber production and phytoremediation of sites contaminated by multi-metals, as it accumulates relative low metal concentrations, but possesses both high biomass and high economic value.
Ramie possesses economic and environmental values in phytoremediation
Double Star/TC‐1 and Cluster data show that both component reconnection and anti‐parallel reconnection occur at the magnetopause when the interplanetary magnetic field (IMF) is predominantly ...dawnward. The occurrence of these different features under these very similar IMF conditions are further confirmed by a statistical study of 290 fast flows measured in both the low and high latitude magnetopause boundary layers. The directions of these fast flows suggest a possible S‐shaped configuration of the reconnection X‐line under such a dawnward dominated IMF orientation.
Pheromonicin-SA (Ph-SA) is a newly developed, engineered multidomain peptide that has a bactericidal effect against Staphylococcus aureus. The objective of this study was to characterize innate ...immune responses by Staph. aureus-stimulated bovine mammary epithelial cells (BMEC) following treatment with Ph-SA. Primary BMEC from one lactating Holstein cow were isolated and exposed to Staph. aureus for 2h, and then treated with rifampicin or Ph-SA. Total RNA was isolated from BMEC at 0, 2, 6, 12, and 24h postinfection, and the mRNA expression of selected genes, including toll-like receptor (TLR)2 and TLR4, IL-1β, IL-6, IL-8, tumor necrosis factor α (TNF-α), and lactoferrin, was quantified by real-time PCR. In the rifampicin group, increases in the expression of mRNA for TNF-α, IL-1β, IL-6, IL-8, and lactoferrin were observed at 6h postinfection and in the expression of mRNA for TLR2 but not for TLR4 at 12h postinfection. In the Ph-SA group, increases in the mRNA expression of TLR2, TNF-α, IL-1β, IL-6, IL-8, and lactoferrin were observed at 6h postinfection, and an increase in TLR4 mRNA expression was observed at 24h postinfection. At 24h postinfection, the mRNA expression of TLR4, TNF-α, IL-1β, IL-6, IL-8, and lactoferrin was higher in the Ph-SA group than in the rifampicin group. In conclusion, Ph-SA might promote the expression of mRNA for TLR2, TLR4, the pro-inflammatory cytokines IL-1, IL-6, and TNF-α, the chemotactic factor IL-8, and lactoferrin in Staph. aureus-infected BMEC. Moreover, Ph-SA may be of value as an antibiotic in promoting innate immune responses by Staph. aureus-infected bovine mammary epithelial cells.
The optical properties of Ba0.6K0.4Fe2As2 have been determined in the normal state for a number of temperatures over a wide frequency range. Two Drude terms, representing two groups of carriers with ...different scattering rates (1/τ), well describe the real part of the optical conductivity σ1(ω). A "broad" Drude component results in an incoherent background with a T-independent 1/τb, while a "narrow" Drude component reveals a T-linear 1/τn resulting in a resistivity ρn≡1/σ1n(ω→0) also linear in temperature. An arctan(T) low-frequency spectral weight is also strong evidence for a T-linear 1/τ. A comparison to other materials with similar behavior suggests that the T-linear 1/τn and ρn in Ba0.6K0.4Fe2As2 originate from scattering from spin fluctuations and hence that an antiferromagnetic quantum critical point is likely to exist in the superconducting dome.
Membrane microparticles and diseases Wu, Z-H; Ji, C-L; Li, H ...
European review for medical and pharmacological sciences,
09/2013, Volume:
17, Issue:
18
Journal Article
Peer reviewed
Membrane microparticles (MPs) are plasma membrane-derived vesicles shed by various types of activated or apoptotic cells including platelets, monocytes, endothelial cells, red blood cells, and ...granulocytes. MPs are being increasingly recognized as important regulators of cell-to-cell interactions. Recent evidences suggest they may play important functions not only in homeostasis but also in the pathogenesis of a number of diseases such as vascular diseases, cancer, infectious diseases and diabetes mellitus. Accordingly, inhibiting the production of MPs may serve as a novel therapeutic strategy for these diseases. Here we review recent advances on the mechanism underlying the generation of MPs and the role of MPs in vascular diseases, cancer, diabetes, inflammation, and pathogen infection.
Epidermal growth factor receptor (EGFR) had been reported as one of the major responsible genes for malignant progression and phenotype reversion of gliomas, and has been used as one of the most ...important therapeutic targets. In the present study, small interference RNA (siRNA) and antisense EGFR expression constructs, which target sequences of human EGFR catalytic domain (2400-2420) and the 3'-coding region, respectively, were used to examine the growth inhibition effects on U251 glioma cells. Cell growth was significantly inhibited and G2/M arrest was observed in antisense- and siRNA-treated groups. Matrigel matrix demonstrated spotted cell clustering pattern in antisense- and siRNA-transfected U251 cells, indicating poor cell growth activities. In addition, the tumor volumes in U251 subcutaneous mice model treated with antisense and siRNA were significantly smaller than those treated with control siRNA and phosphate-buffered saline. Also, glial fibrillary acidic protein expression was upregulated in antisense- and siRNA-treated groups than the control groups. Our results demonstrated that antisense- or siRNA-targeting intracellular region of EGFR can inhibit EGFR expression, exerted growth inhibition effect on U251 glioma cells in vitro and in vivo. Consequently, siRNA expression plasmid-mediated gene therapy would be a new strategy in treatment of gliomas.