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81.
CO2 utilization in upsteam oil and gas applications requires CO2-soluble additives such as polymers, surfactants, and other components. Here we report the facile synthesis of CO2-soluble oxidizers composed of judiciously selected organic cations paired with oxidizing anions. [Bu4N]BrO3 and [Bu4N]ClO3 are prepared using a double displacement synthetic strategy, whereby the crystalline product is readily obtained in high yield and structurally characterized using single-crystal X-ray diffraction. The facility of the approach is demonstrated through the preparation of several additional alkylammonium bromate compounds. Static solubility studies using a high-pressure cell with viewing windows showed that tetrabutylammonium compounds could be solubilized using cosolvent-modified CO2. Using 4 mol% ethanol as cosolvent, >3 mM [Bu4N]BrO3 could be dissolved in CO2, while ∼0.75 mM [Bu4N]ClO3 could be dissolved in the same solvent system. The solubility properties of [Bu4N]BrO3 along with its thermal stability up to ∼200 °C suggest that it is a promising oilfield oxidizer that can be utilized in subterranean CO2 applications.Bromate and chlorate salts were hydrophobically modified with tetrabutylammonium to yield oxidizers that are soluble in CO2-cosolvent mixtures. 相似文献
82.
Use of telbivudine in kidney transplant recipients with chronic hepatitis B virus infection: A preliminary experience 下载免费PDF全文
Telbivudine is a relatively novel oral nucleoside analogue with favourable efficacy and tolerability in treatment‐naïve chronic hepatitis B virus (HBV) infection, but its data in kidney transplant recipients (KTRs) was lacking. The efficacy and tolerability of telbivudine in four treatment‐naïve HBsAg‐positive KTRs were reviewed (treatment duration 54 (36–72) months) HBV DNA declined from 2.6 × 105(7.8 × 103–1.5 × 107) copies/mL at baseline to 170 (0.0–3.2 × 104) copies/mL at 12 months, and became undetectable at 24 and 36 months (P = 0.060, 0.118 and 0.005 compared with baseline). Alanine aminotransferase levels dropped from 46.5 (30–48) IU/mL at baseline to 28 (13–45) IU/mL, 34.5 (15–71) IU/mL and 26 (12–41) IU/mL at 12, 24 and 36 months, respectively (P = 0.109, 0.715 and 0.068 compared with baseline). Serum creatinine level and estimated glomerular filtration rate (eGFR) remained stable after 36 months of treatment (P all > 0.05 compared with baseline). No virological breakthrough, cirrhosis or hepatocellular carcinoma occurred. Our pilot data suggests that telbivudine has favourable efficacy and renal safety profiles in HBsAg‐positive KTRs. 相似文献
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84.
Inflammation and dephosphorylation of the tight junction protein occludin in an experimental model of multiple sclerosis 总被引:3,自引:0,他引:3
Morgan L Shah B Rivers LE Barden L Groom AJ Chung R Higazi D Desmond H Smith T Staddon JM 《Neuroscience》2007,147(3):664-673
Multiple sclerosis (MS) is a disease of the CNS in which inflammation, demyelination and neurodegeneration contribute to its initiation and progression. A frequently employed model of MS is experimental autoimmune encephalomyelitis (EAE). Here, to gain new insights into the disease process, an analysis of proteins in extracts of lumbar spinal cord from naïve and EAE rats was undertaken. The data mainly confirm that inflammation and blood–brain barrier (BBB) breakdown are the major hallmarks of disease in this model. Given their importance in the BBB, junctional proteins were further investigated. Occludin, a protein localizing to tight junctions in brain endothelial cells, showed strikingly increased migration in EAE when analyzed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE). This increased migration was mimicked by in vitro phosphatase treatment, implying its dephosphorylation in EAE. Occludin dephosphorylation coincided with the onset of inflammation, slightly preceding visible signs of disease, and was just prior to apparent changes in BBB permeability. These findings suggest occludin is a target for signaling processes in EAE, perhaps regulating the response of the BBB to the inflammatory environment as seen in MS. 相似文献
85.
Watts HR Vince V Walsh DT Bresciani LG Gentleman SM Jen LS Anderson PJ 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,181(1):69-77
Accumulating evidence indicates that mutations in the presenilin 1 (PS1) gene are responsible for most cases of familial Alzheimer’s
disease (AD). Although its biological functions are not yet fully understood, it appears that PS1 plays a role in the processing
and trafficking of the amyloid precursor protein (APP). However, little is known about factors that are involved in regulating
the metabolism of PS1 especially in relation to AD pathology. In this study, we have examined the effect of optic nerve crush,
intravitreal injection of the inflammatory agent lipopolysaccharide (LPS) or injection of amyloid β1-42 (Aβ1-42) on the expression and processing of PS1 in the rat retina. We found that 48 h after injection of Aβ1-42 there was a dramatic alteration in the banding pattern of PS1 on Western blots, as indicated by marked changes in the levels
of expression of some of its C- and N-terminal fragments in retinal homogenates. These results suggest an Aβ1-42-induced potentiation of a non-specific stress-related but inflammation-independent alteration of processing of PS1 in this
in vivo model. 相似文献
86.
Andrew D. Frugé Travis Ptacek Yuko Tsuruta Casey D. Morrow Maria Azrad Renee A. Desmond Gary R. Hunter Soroush Rais-Bahrami Wendy Demark-Wahnefried 《Journal of the Academy of Nutrition and Dietetics》2018,118(4):714-723.e1
Background
Diet and obesity influence prostate cancer risk and progression–effects that may be mediated through the gut microbiome.Objective
Our aim was to explore relationships among diet, gut microbes, and Gleason sum in overweight and obese prostate cancer patients enrolled in a presurgical weight-loss trial.Design
Randomized controlled trial (NCT01886677) secondary analysis.Participants/setting
In 2013-2014, 40 prostate cancer patients in the southeastern United States were randomized and allocated equally to weight-loss and wait-list control arms while they awaited prostatectomy; stool samples were collected on a subset of 22 patients.Intervention
Registered dietitian nutritionists and exercise physiologists provided semi-weekly in-person and telephone-based guidance on calorie-restricted diets and exercise to promote an approximate weight loss of 0.91 kg/wk.Main outcome measures
Baseline and follow-up 24-hour dietary recalls were conducted and analyzed (using the Automated Self-Administered 24-hour dietary recall system; National Cancer Institute, Bethesda, MD) for macronutrients, micronutrients, and food groups. Microbiome analysis targeting the V4 region of the 16S ribosomal RNA gene was performed on fecal samples. Biopsy Gleason sum data were accessed from diagnostic pathology reports.Statistical analyses performed
Associations between dietary factors and operational taxonomic units were determined by β-diversity analysis. Wilcoxon signed rank, and Mann-Whitney U testing assessed within- and between-arm differences. Associations between Gleason sum and operational taxonomic units, and diet and operational taxonomic units, were analyzed using Spearman correlations.Results
At baseline, Proteobacteria (median 0.06, interquartile range 0.01 to 0.16) were abundant, with four orders positively associated with Gleason sum. Gleason sum was associated with Clostridium (ρ=.579; P=0.005) and Blautia (ρ=?0.425, P=0.049). Increased red meat consumption from baseline was associated with Prevotella (ρ=?.497; P=0.018) and Blautia (ρ=.422; P=0.039). Men who increased poultry intake had decreased Clostridiales abundance (P=0.009).Conclusions
This hypothesis-generating study provides a starting point for investigating the relationships between the fecal microbiome, diet, and prostate cancer. Adequately powered studies are required to further explore and validate these findings. 相似文献87.
Quek DL Ng YY Wang W Tan AS Tang-Lim GI Ng IS Law HY Chong SS 《Clinical biochemistry》2007,40(5-6):427-430
OBJECTIVES: This study aimed to evaluate a rapid molecular carrier screening strategy for beta-thalassemia. DESIGN AND METHODS: Allele-specific PCR was combined with amplicon detection by dissociation curve analysis of SYBR Green I fluorescence in a single step. RESULTS: The presence of a particular mutation results in the amplification of a mutation-specific product and the dissociation temperature of each amplicon was highly reproducible. CONCLUSIONS: Homogeneous allele-specific PCR amplification and detection of multiple beta-globin mutations can serve as a rapid and inexpensive carrier screening tool. 相似文献
88.
89.
Neil Dawson Martin McDonald Desmond J Higham Brian J Morris Judith A Pratt 《Neuropsychopharmacology》2014,39(7):1786-1798
Acute treatment with subanesthetic ketamine, a non-competitive N-methyl-D-aspartic acid (NMDA) receptor antagonist, is widely utilized as a translational model for schizophrenia. However, how acute NMDA receptor blockade impacts on brain functioning at a systems level, to elicit translationally relevant symptomatology and behavioral deficits, has not yet been determined. Here, for the first time, we apply established and recently validated topological measures from network science to brain imaging data gained from ketamine-treated mice to elucidate how acute NMDA receptor blockade impacts on the properties of functional brain networks. We show that the effects of acute ketamine treatment on the global properties of these networks are divergent from those widely reported in schizophrenia. Where acute NMDA receptor blockade promotes hyperconnectivity in functional brain networks, pronounced dysconnectivity is found in schizophrenia. We also show that acute ketamine treatment increases the connectivity and importance of prefrontal and thalamic brain regions in brain networks, a finding also divergent to alterations seen in schizophrenia. In addition, we characterize how ketamine impacts on bipartite functional interactions between neural subsystems. A key feature includes the enhancement of prefrontal cortex (PFC)-neuromodulatory subsystem connectivity in ketamine-treated animals, a finding consistent with the known effects of ketamine on PFC neurotransmitter levels. Overall, our data suggest that, at a systems level, acute ketamine-induced alterations in brain network connectivity do not parallel those seen in chronic schizophrenia. Hence, the mechanisms through which acute ketamine treatment induces translationally relevant symptomatology may differ from those in chronic schizophrenia. Future effort should therefore be dedicated to resolve the conflicting observations between this putative translational model and schizophrenia. 相似文献