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1.
Charles A. Kunos Jeffrey M. Fabien John P. Shanahan Christine Collen Thierry Gevaert Kenneth Poels Robbe Van den Begin Benedikt Engels Mark De Ridder 《Journal of visualized experiments : JoVE》2015,(100)
Physicians considering stereotactic ablative body radiation therapy (SBRT) for the treatment of extracranial cancer targets must be aware of the sizeable risks for normal tissue injury and the hazards of physical tumor miss. A first-of-its-kind SBRT platform achieves high-precision ablative radiation treatment through a combination of versatile real-time imaging solutions and sophisticated tumor tracking capabilities. It uses dual-diagnostic kV x-ray units for stereoscopic open-loop feedback of cancer target intrafraction movement occurring as a consequence of respiratory motions and heartbeat. Image-guided feedback drives a gimbaled radiation accelerator (maximum 15 x 15 cm field size) capable of real-time ±4 cm pan-and-tilt action. Robot-driven ±60° pivots of an integrated ±185° rotational gantry allow for coplanar and non-coplanar accelerator beam set-up angles, ultimately permitting unique treatment degrees of freedom. State-of-the-art software aids real-time six dimensional positioning, ensuring irradiation of cancer targets with sub-millimeter accuracy (0.4 mm at isocenter). Use of these features enables treating physicians to steer radiation dose to cancer tumor targets while simultaneously reducing radiation dose to normal tissues. By adding respiration correlated computed tomography (CT) and 2-[18F] fluoro-2-deoxy-ᴅ-glucose (18F-FDG) positron emission tomography (PET) images into the planning system for enhanced tumor target contouring, the likelihood of physical tumor miss becomes substantially less1. In this article, we describe new radiation plans for the treatment of moving lung tumors. 相似文献
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3.
Tiffany M. Nuessle Nicole L. Garneau Meghan M. Sloan Stephanie A. Santorico 《Journal of visualized experiments : JoVE》2015,(100)
The goal of the Denver Papillae Protocol is to use a dichotomous key to define and prioritize the characteristics of fungiform papillae (FP) to ensure consistent scoring between scorers. This protocol builds off of a need that has arisen from the last two decades of taste research using FP as a proxy for taste pore density. FP density has historically been analyzed using Miller & Reedy’s 1990 characterizations of their morphology: round, stained lighter, large, and elevated. In this work, the authors forewarned that stricter definitions of FP morphology needed to be outlined. Despite this call to action, follow up literature has been scarce, with most studies continuing to cite Miller & Reedy’s original work. Consequently, FP density reports have been highly variable and, combined with small sample sizes, may contribute to the discrepant conclusions on the role of FP in taste sensitivity. The Genetics of Taste Lab explored this apparent inconsistency in counting and found that scorers were individually prioritizing the importance of these characteristics differently and had no guidance for when a papilla had some, but not all, of the reported qualities of FP. The result of this subjectivity is highly variable FP counts of the same tongue image. The Denver Papillae Protocol has been developed to remedy this consequence through use of a dichotomous key that further defines and prioritizes the importance of the characteristics put forth by Miller & Reedy. The proposed method could help create a standard way to quantify FP for researchers in the field of taste and nutritional studies. 相似文献
4.
Rudi F. Vogel Martin Lohmann rea N. Weller Marta Hugas Walter P. Hammes 《FEMS microbiology letters》1991,84(2):183-190
Plasmid profiles of strains of Lactobacillus curvatus and L. sake isolated from meat or sauerkraut were analysed to investigate plasmid homology and distribution in relation to the ecology of these organisms in fermenting foods. A hybridisation probe was constructed by cloning of pLc2, a cryptic, 2.6-kbp plasmid from L. curvatus LTH683, into the Escherichia coli plasmid pRV50. In Southern hybridisations with the digoxygenine labeled pLc2 probe, pLc2-related small plasmids were frequently detected in meat-borne strains of L. casei subsp. pseudoplantarum, L. curvatus, L. sake, L. alimentarius, L. farciminis and L. halotolerans and in L. curvatus and L. sake isolated from sauerkraut. Among 27 Lactobacillus type strains originally isolated from habitats other than meat this type of homology was detected only with plasmids of L. buchneri and L. mali. Restriction-enzyme mapping of six small cryptic plasmids from L. curvatus and L. sake revealed strong structural homology but no similarity to previously characterized plasmids of lactobacilli. The presence of a variable region in addition to a conserved one and the occurrence of deletions during cloning of pLc2 suggest that vectors derived from these plasmids are likely to be structurally unstable. 相似文献
5.
A. S?ber 《Photosynthetica》1997,34(4):599-603
A positive correlation was found between steady state values of hydraulic (L
pA) and stomatal conductance (g
s) of French bean leaves: both were lower in the dark than in the light and lower in water-deficient plants than in the well-watered
ones. The relative rate of stomatal opening after a pressure rise in the xylem was also positively related to L
pA. The L
pA and g
s were both related to the maximal photosynthetic rate at saturating CO2 concentrations.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
α-Glucosidase is a catabolic enzyme that regulates the body’s plasma glucose levels by providing energy sources to maintain healthy functioning. 2-Amino-thiadiazole (1–13) and 2-amino-thiadiazole based Schiff bases (14–22) were synthesized, characterized by 1H NMR and HREI-MS and screened for α-glucosidase inhibitory activity. All twenty-two (22) analogs exhibit varied degree of α-glucosidase inhibitory potential with IC50 values ranging between 2.30 ± 0.1 to 38.30 ± 0.7 μM, when compare with standard drug acarbose having IC50 value of 39.60 ± 0.70 μM. Among the series eight derivatives 1, 2, 6, 7, 14, 17, 19 and 20 showed outstanding α-glucosidase inhibitory potential with IC50 values of 3.30 ± 0.1, 5.80 ± 0.2, 2.30 ± 0.1, 2.70 ± 0.1, 2.30 ± 0.1, 5.50 ± 0.1, 4.70 ± 0.2, and 5.50 ± 0.2 μM respectively, which is many fold better than the standard drug acarbose. The remaining analogs showed good to excellent α-glucosidase inhibition. Structure activity relationship has been established for all compounds. The binding interactions of these compounds were confirmed through molecular docking. 相似文献
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8.
《Bioorganic & medicinal chemistry》2014,22(1):141-147
A series of new sulfonamides was prepared starting from 2-oxo-N′-(4-sulfamoylphenyl)-propanehydrazonoyl chloride, a sulfanilamide derivative, which was reacted with aroylhydrazides, amines, or thiols. A library of derivatives incorporating aroylhydrazone, [1,2,4]triazolo[3,4-b][1,3,4]thiadiazinyl- or 2-(cyanophenyl-methylene)-1,3,4-thiadiazol-3(2H)-yl moieties was thus synthesized. The new compounds were investigated as inhibitors of four α-carbonic anhydrases (CAs, EC 4.2.1.1), the human (h) isoforms hCA I and II, and the bacterial ones recently isolated from the extremophilic bacteria Sulfurihydrogenibium yellostonense (SspCA) and Sulfurihydrogenibium azorense (SazCA). Low nanomolar activity was observed against hCA II (KIs of 0.56–17.1 nM) whereas hCA I was less inhibited by these compounds (KIs of 86.4 nM–32.8 μM). The bacterial CAs were also effectively inhibited by these derivatives (KIs in the range of 0.77–234 nM against SazCA, and of 6.2–89.1 against SspCA, respectively), with several low nanomolar/subnanomolar inhibitors detected against both of them. As SspCA and SazCA are among the most thermostable and catalytically active CAs, it is of interest to find modulators of their activity for potential biotechnologic applications. 相似文献
9.
《Bioorganic & medicinal chemistry》2014,22(22):6324-6332
The blood coagulation cascade represents an attractive target for antithrombotic drug development, and recent studies have attempted to identify oral anticoagulants with inhibitory activity for enzymes in this cascade, with particular attention focused on thrombin and factor Xa (fXa) as typical targets. We previously described the discovery of the orally active fXa inhibitor darexaban (1) and reported a unique profile that compound 1 rapidly transformed into glucuronide YM-222714 (2) after oral administration. Here, we propose a novel strategy towards the discovery of an orally active anticoagulant that is based on the bioconversion of a non-amidine inhibitor into the corresponding conjugate to boost ex vivo anticoagulant activity via an increase in hydrophilicity. Computational molecular modeling was utilized to select a template scaffold and design a substitution point to install a potential functional group for conjugation. This strategy led to the identification of the phenol-derived fXa inhibitor ASP8102 (14), which demonstrated highly potent anticoagulant activity after biotransformation into the corresponding glucuronide (16) via oral dosing. 相似文献
10.