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91.

Objective

Human tumor cell lines form the basis of the majority of present day laboratory cancer research. These models are vital to studying the molecular biology of tumors and preclinical testing of new therapies. When compared to traditional adherent cell lines, suspension cell lines recapitulate the genetic profiles and histologic features of glioblastoma multiforme (GBM) with higher fidelity. Using a modified neural stem cell culture technique, here we report the characterization of GBM cell lines including GBM variants.

Methods

Tumor tissue samples were obtained intra-operatively and cultured in neural stem cell conditions containing growth factors. Tumor lines were characterized in vitro using differentiation assays followed by immunostaining for lineage-specific markers. In vivo tumor formation was assayed by orthotopic injection in nude mice. Genetic uniqueness was confirmed via short tandem repeat (STR) DNA profiling.

Results

Thirteen oncosphere lines derived from GBM and GBM variants, including a GBM with PNET features and a GBM with oligodendroglioma component, were established. All unique lines showed distinct genetic profiles by STR profiling. The lines assayed demonstrated a range of in vitro growth rates. Multipotency was confirmed using in vitro differentiation. Tumor formation demonstrated histologic features consistent with high grade gliomas, including invasion, necrosis, abnormal vascularization, and high mitotic rate. Xenografts derived from the GBM variants maintained histopathological features of the primary tumors.

Conclusions

We have generated and characterized GBM suspension lines derived from patients with GBMs and GBM variants. These oncosphere cell lines will expand the resources available for preclinical study.  相似文献   
92.
As part of a detailed study, the syntheses, biological activities, and pharmacokinetic properties of hydroxylated analogues of the previously described broad spectrum antifungal agents, Sch 51048 (1), Sch 50001 (3), and Sch 50002 (4), are described. Based on an overall superior profile, one of the alcohols, Sch 56592 (2), was selected for clinical studies.  相似文献   
93.
Summary The possibility of usingZymomonas mobilis as the microorganism, in solid-state fermentation of sugar-beet particles was investigated. The major factors affecting the process were investigated and related to ethanol yield and productivity. Ethanol yield of 0.48 g/g sugar, volumetric productivity of 12 g/L h, and final ethanol concentration of 130 g/L show the good performance ofZ.mobilis in a solid-state fermentation.  相似文献   
94.
The risk for lethal ventricular arrhythmias is increased in individuals who carry mutations in genes that encode cardiac ion channels. Loss-of-function mutations in SCN5A, the gene encoding the cardiac sodium channel, are linked to Brugada syndrome (BrS). Arrhythmias in BrS are often preceded by coved-type ST-segment elevation in the right-precordial leads V1 and V2. Loss-of-function mutations in KCNH2, the gene encoding the cardiac ion channel that is responsible for the rapidly activating delayed rectifying potassium current, are linked to long-QT syndrome type 2 (LQT-2). LQT-2 is characterised by delayed cardiac repolarisation and rate-corrected QT interval (QTc) prolongation. Here, we report that the risk for ventricular arrhythmias in BrS and LQT-2 is further increased during fever. Moreover, we demonstrate that fever may aggravate coved-type ST-segment elevation in BrS, and cause QTc lengthening in LQT-2. Finally, we describe molecular mechanisms that may underlie the proarrhythmic effects of fever in BrS and LQT-2. (Neth Heart J 2010;18:165-9.)  相似文献   
95.
Aquatic Ecology - More has yet to be indicated on the ability of microphyte plants for the removal of heavy metals from contaminated environments. In the present research, the ability of the...  相似文献   
96.
Hemispheric asymmetry of a wide range of functions is a hallmark of the human brain. The visual system has traditionally been thought of as symmetrically distributed in the brain, but a growing body of evidence has challenged this view. Some highly specific visual tasks have been shown to depend on hemispheric specialization. However, the possible lateralization of cerebral responses to a simple checkerboard visual stimulation has not been a focus of previous studies. To investigate this, we performed two sessions of blood-oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) in 54 healthy subjects during stimulation with a black and white checkerboard visual stimulus. While carefully excluding possible non-physiological causes of left-to-right bias, we compared the activation of the left and the right cerebral hemispheres and related this to grey matter volume, handedness, age, gender, ocular dominance, interocular difference in visual acuity, as well as line-bisection performance. We found a general lateralization of cerebral activation towards the right hemisphere of early visual cortical areas and areas of higher-level visual processing, involved in visuospatial attention, especially in top-down (i.e., goal-oriented) attentional processing. This right hemisphere lateralization was partly, but not completely, explained by an increased grey matter volume in the right hemisphere of the early visual areas. Difference in activation of the superior parietal lobule was correlated with subject age, suggesting a shift towards the left hemisphere with increasing age. Our findings suggest a right-hemispheric dominance of these areas, which could lend support to the generally observed leftward visual attentional bias and to the left hemifield advantage for some visual perception tasks.  相似文献   
97.
Neohesperidin dihydrochalcone (NHDC) was recently introduced as an activator of mammalian alpha‐amylase. In the current study, the effect of NHDC has been investigated on bacterial and fungal alpha‐amylases. Enzyme assays and kinetic analysis demonstrated the capability of NHDC to significantly activate both tested alpha‐amylases. The ligand activation pattern was found to be more similar between the fungal and mammalian enzyme in comparison with the bacterial one. Further, thermostability experiments indicated a stability increase in the presence of NHDC for the bacterial enzyme. In silico (docking) test locates a putative binding site for NHDC on alpha‐amylase surface in domain B. This domain shows differences in various alpha‐amylase types, and the different behavior of the ligand toward the studied enzymes may be attributed to this fact. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
98.
99.

Background

Circulating cell-free (ccf) fetal DNA comprises 3–20% of all the cell-free DNA present in maternal plasma. Numerous research and clinical studies have described the analysis of ccf DNA using next generation sequencing for the detection of fetal aneuploidies with high sensitivity and specificity. We sought to extend the utility of this approach by assessing semi-automated library preparation, higher sample multiplexing during sequencing, and improved bioinformatic tools to enable a higher throughput, more efficient assay while maintaining or improving clinical performance.

Methods

Whole blood (10mL) was collected from pregnant female donors and plasma separated using centrifugation. Ccf DNA was extracted using column-based methods. Libraries were prepared using an optimized semi-automated library preparation method and sequenced on an Illumina HiSeq2000 sequencer in a 12-plex format. Z-scores were calculated for affected chromosomes using a robust method after normalization and genomic segment filtering. Classification was based upon a standard normal transformed cutoff value of z = 3 for chromosome 21 and z = 3.95 for chromosomes 18 and 13.

Results

Two parallel assay development studies using a total of more than 1900 ccf DNA samples were performed to evaluate the technical feasibility of automating library preparation and increasing the sample multiplexing level. These processes were subsequently combined and a study of 1587 samples was completed to verify the stability of the process-optimized assay. Finally, an unblinded clinical evaluation of 1269 euploid and aneuploid samples utilizing this high-throughput assay coupled to improved bioinformatic procedures was performed. We were able to correctly detect all aneuploid cases with extremely low false positive rates of 0.09%, <0.01%, and 0.08% for trisomies 21, 18, and 13, respectively.

Conclusions

These data suggest that the developed laboratory methods in concert with improved bioinformatic approaches enable higher sample throughput while maintaining high classification accuracy.  相似文献   
100.
Exercise is a potent stimulus against cardiac ischemia reperfusion (IR) injury, although the protective mechanisms are not completely understood. The study purpose was to examine whether the mitochondrial or sarcolemmal ATP-sensitive potassium channel (mito K(ATP) or sarc K(ATP), respectively) mediates exercise-induced cardioprotection against post-IR cell death and apoptosis. Eighty-six, 4-mo-old male Sprague Dawley rats were randomly assigned to treadmill exercise (Ex; 30 m/min, 3 days, 60 min, ~70 maximal oxygen uptake) and sedentary (Sed) treatments. Rats were exposed to regional cardiac ischemia (50 min) and reperfusion (120 min) or Sham (170 min; no ligation) surgeries. Exercise subgroups received placebo (saline), 5-hydroxydecanoate (5HD; 10 mg/kg ip), or HMR1098 (10 mg/kg ip) to inhibit mito K(ATP) or sarc K(ATP) channel. Comprehensive outcome assessments included post-IR ECG arrhythmias, cardiac tissue necrosis, redox perturbations, and autophagy biomarkers. No arrhythmia differences existed between exercised and sedentary hearts following extended-duration IR (P < 0.05). The sarc K(ATP) channel was confirmed essential (P = 0.002) for prevention of antinecrotic tissue death with exercise (percent infarct, Sed = 42%; Ex = 20%; Ex5HD = 16%; ExHMR = 42%), although neither the mito K(ATP) (P = 0.177) nor sarc K(ATP) (P = 0.274) channel provided post-IR protection against apoptosis (terminal deoxynucleotidyl transferase deoxy UTP-mediated nick-end labeling-positive nuclei/mm(2), Sham = 1.8 ± 0.5; Sed = 19.4 ± 6.7; Ex = 7.5 ± 4.6; Ex5HD = 14.0 ± 3.9; ExHMR = 11.1 ± 1.8). Exercise preconditioning also appears to preserve basal autophagy levels, as assessed by Beclin 1 (P ≤ 0.001), microtubule-associated protein-1 light-chain 3B ratios (P = 0.020), and P62 (P ≤ 0.001), in the hours immediately following IR. Further research is needed to better understand these findings and corresponding redox changes in exercised hearts.  相似文献   
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