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91.
92.
ObjectiveComparison of a fully-automated segmentation method that uses compartmental volume information to a semi-automatic user-guided and FDA-approved segmentation technique.MethodsNineteen patients with a recently diagnosed and histologically confirmed glioblastoma (GBM) were included and MR images were acquired with a 1.5 T MR scanner. Manual segmentation for volumetric analyses was performed using the open source software 3D Slicer version 4.2.2.3 (www.slicer.org). Semi-automatic segmentation was done by four independent neurosurgeons and neuroradiologists using the computer-assisted segmentation tool SmartBrush® (referred to as SB), a semi-automatic user-guided and FDA-approved tumor-outlining program that uses contour expansion. Fully automatic segmentations were performed with the Brain Tumor Image Analysis (BraTumIA, referred to as BT) software. We compared manual (ground truth, referred to as GT), computer-assisted (SB) and fully-automated (BT) segmentations with regard to: (1) products of two maximum diameters for 2D measurements, (2) the Dice coefficient, (3) the positive predictive value, (4) the sensitivity and (5) the volume error.ResultsSegmentations by the four expert raters resulted in a mean Dice coefficient between 0.72 and 0.77 using SB. BT achieved a mean Dice coefficient of 0.68. Significant differences were found for intermodal (BT vs. SB) and for intramodal (four SB expert raters) performances. The BT and SB segmentations of the contrast-enhancing volumes achieved a high correlation with the GT. Pearson correlation was 0.8 for BT; however, there were a few discrepancies between raters (BT and SB 1 only). Additional non-enhancing tumor tissue extending the SB volumes was found with BT in 16/19 cases. The clinically motivated sum of products of diameters measure (SPD) revealed neither significant intermodal nor intramodal variations. The analysis time for the four expert raters was faster (1 minute and 47 seconds to 3 minutes and 39 seconds) than with BT (5 minutes).ConclusionBT and SB provide comparable segmentation results in a clinical setting. SB provided similar SPD measures to BT and GT, but differed in the volume analysis in one of the four clinical raters. A major strength of BT may its independence from human interactions, it can thus be employed to handle large datasets and to associate tumor volumes with clinical and/or molecular datasets ("-omics") as well as for clinical analyses of brain tumor compartment volumes as baseline outcome parameters. Due to its multi-compartment segmentation it may provide information about GBM subcompartment compositions that may be subjected to clinical studies to investigate the delineation of the target volumes for adjuvant therapies in the future.  相似文献   
93.
RAPD analysis in selected cultivars of Kapoori and Bangla betel vines (Piper betle L.) were carried out in order to ascertain the relatedness of the two to each other. On the basis of the data from 10 RAPD primers, it was found that the Kapoori cultivars were more heterogeneous (mean SI = 0.521) while the Bangla cultivars were mostly similar to each other (mean SI = 0.884). Within each type, the overall polymorphism of RAPD bands was more than 70 %. When RAPD band data for both types of cultivars were considered cumulatively, the two were clearly separated from each other. In fact only six bands out of a total of 60 bands were found to be common to cultivars of both types. Bands specific to only one of the two types have potential for developing betel vine cultivar-specific probes and SCAR-markers.  相似文献   
94.

Objective:

Numerous indexes of adiposity have been proposed and are currently in use in clinical practice and research. However, the correlation of these indexes with measures of vascular health remain poorly defined. This study investigated which measure of adiposity is most strongly associated with endothelial function.

Design and Methods:

Data from the Firefighters And Their Endothelium (FATE) study was used. The relationships between three measures of vascular function: flow‐mediated dilation (FMD), hyperemic velocity time integral (VTI), and hyperemic shear stress (HSS), and five measures of adiposity: BMI, waist circumference (WC), waist‐to‐hip ratio (WHR), waist‐to‐height ratio (WHtR), and body adiposity index (BAI) were tested. Univariate comparisons were made, and subsequently models adjusted for traditional risk factors were constructed.

Results:

A total of 1,462 male firefighters (mean age 49 ± 9) without cardiovascular disease comprised the study population. No measure of adiposity correlated with FMD; all five measures of adiposity were negatively correlated with VTI and HSS (P values <0.0001), with WHtR most strongly correlated with VTI, and WC most strongly correlated with HSS (both P < 0.05). In models including all five measures of obesity simultaneously, BMI, WC, and WHtR were all predictive of HSS (all P values <0.05), and BMI and WHR were both predictive of VTI (P values <0.05).

Conclusions:

Anthropometric measures of adiposity may help refine estimations of atherosclerotic burden. BMI was most consistently associated with endothelial dysfunction, but measures of adiposity that reflect distribution of mass were additive.  相似文献   
95.
A strain, Stenotrophomonas HPC383 is isolated from effluent treatment plant treating wastewater from pesticide industry; degrades various aromatic compounds (cresols, phenol, catechol, 4methyl-catechol and hydroquinone) and crude oil, as determined through HPLC and GC analysis. Culture HPC383 could degrade (%) various compounds (1 mM) from a mixture: phenol - 99, p-cresol - 100, 4-methylcatechol - 96 and hydroquinone - 43 within 48 h of incubation, whereas it took 7 days to degrade 94% of 0.5% crude oil. Gene locus dmpN, to identify phenol degrading capacity was determined by PCR followed by southern analysis. The sequenced DNA fragment exhibited 99% sequence similarity to phenol hydroxylase gene from Arthrobacter sp. W1 (FJ610336). Amino acid sequence analysis of phenol hydroxylase reveals it to belong to high-Ks (affinity constant) group. Application of HPC383 in bioremediation of aquatic and terrestrial sites contaminated with petrochemical has been suggested.  相似文献   
96.
97.
Elevated vascular endothelial growth factor (VEGF) and complement activation are implicated in the pathogenesis of different ocular diseases. The objective of this study was to investigate the hypothesis that dual inhibition of both VEGF and complement activation would confer better protection against ocular inflammation and neovascularization. In this study, we engineered a secreted chimeric VEGF inhibitor domain (VID), a complement inhibitor domain (CID) and a dual inhibitor (ACVP1). Vectors expressing these three inhibitors were constructed and packaged into AAV2 (sextY‐F) particles. The expression and secretion of the proteins were validated by Western blot. The effects of these inhibitors expressed from AAV2 vectors were examined in endotoxin‐induced uveitis (EIU), experimental autoimmune uveoretinitis (EAU) and choroidal neovascularization (CNV) mouse models. The AAV2 vectors expressing the CID‐ and ACVP1‐attenuated inflammation in EIU and EAU model, whereas the vector expressing VID showed improved retinal structure damaged by EAU, but not affect the infiltration of inflammatory cells in EAU or EIU eyes. Both VID and CID vectors improved laser‐induced retinal and choroid/RPE injuries and CNV, whereas ACVP1 vector provided significantly better protection. Our results suggest that gene therapy targeting VEGF and complement components could provide an innovative and long‐term strategy for ocular inflammatory and neovascular diseases.  相似文献   
98.
99.
Heavy water caused marked gradual decrease in the weight of the body as well as the testes throughout the treatment interval ranging from 1 to 6 weeks. Following D2O oral administration, an overall significant fall in the activity of acid phosphatase and glucose-6-phosphatase was registered. On the other hand, the activity of lactic and succinic dehydrogenases, alkaline phosphatase and adenosine triphosphatase increases following D2O treatment. These changes in the enzyme activity are suggestive of an altered metabolism of the testes in response to D2O administration. Our data corroborate the view that biological systems do discriminate between H2 and D2.  相似文献   
100.
The H1N1 2009 influenza virus (H1N1pdm09) pandemic had several unexpected features, including low morbidity and mortality in older populations. We performed in-depth evaluation of antibody responses generated following H1N1pdm09 infection of naïve ferrets and of 130 humans ranging from the very young (0 to 9 years old) to the very old (70 to 89 years old). In addition to hemagglutination inhibition (HI) titers, we used H1N1pdm09 whole-genome-fragment phage display libraries (GFPDL) to evaluate the antibody repertoires against internal genes, hemagglutinin (HA), and neuraminidase (NA) and also measured antibody affinity for antigenic domains within HA. GFPDL analyses of H1N1pdm09-infected ferrets demonstrated gradual development of antibody repertoires with a focus on M1 and HA1 by day 21 postinfection. In humans, H1N1pdm09 infection in the elderly (>70 years old) induced antibodies with broader epitope recognition in both the internal genes and the HA1 receptor binding domain (RBD) than for the younger age groups (0 to 69 years). Importantly, post-H1N1 infection serum antibodies from the elderly demonstrated substantially higher avidity for recombinant HA1 (rHA1) (but not HA2) than those from younger subjects (50% versus <22% 7 M urea resistance, respectively) and lower antibody dissociation rates using surface plasmon resonance. This is the first study in humans that provides evidence for a qualitatively superior antibody response in the elderly following H1N1pdm09 infection, indicative of recall of long-term memory B cells or long-lived plasma cells. These findings may help explain the age-related morbidity and mortality pattern observed during the H1N1pdm09 pandemic.  相似文献   
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