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61.
We present a new approach for computing the voxelized Minkowski sum (excluding any enclosed voids) of two polyhedral objects using programmable Graphics Processing Units (GPUs). We first cull out surface primitives that will not contribute to the final boundary of the Minkowski sum, analyzing and adaptively bounding the rounding errors of the culling algorithm to solve the floating point error problem. The remaining surface primitives are then rendered to depth textures along six orthogonal directions to generate an initial solid voxelization of the Minkowski sum. Finally we employ fast flood fill to find all the outside voxels. We generate both solid and surface voxelizations of Minkowski sums without enclosed voids and support high volumetric resolution of 10243 with low video memory cost. The whole algorithm runs on the GPU and is at least one order of magnitude faster than existing boundary representation (B-rep) based algorithms. It avoids the large number of 3D Boolean operations needed in most existing algorithms and is easy to implement. The voxelized Minkowski sums can be used in a variety of applications including motion planning and penetration depth computation. 相似文献
62.
Grgoire B. Morand Isabel Cardona Sara Brito Silva Costa Cruz Alex M. Mlynarek Michael P. Hier Moulay A. Alaoui-Jamali Sabrina Daniela da Silva 《International journal of molecular sciences》2022,23(15)
The rise in human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) has prompted a quest for further understanding of the role of high-risk HPV in tumor initiation and progression. Patients with HPV-positive OPSCC (HPV+ OPSCC) have better prognoses than their HPV-negative counterparts; however, current therapeutic strategies for HPV+ OPSCC are overly aggressive and leave patients with life-long sequalae and poor quality of life. This highlights a need for customized treatment. Several clinical trials of treatment de-intensification to reduce acute and late toxicity without compromising efficacy have been conducted. This article reviews the differences and similarities in the pathogenesis and progression of HPV-related OPSCC compared to cervical cancer, with emphasis on the role of prophylactic and therapeutic vaccines as a potential de-intensification treatment strategy. Overall, the future development of novel and effective therapeutic agents for HPV-associated head and neck tumors promises to meet the challenges posed by this growing epidemic. 相似文献
63.
Sara Silva Kaido Kurrikoff Ülo Langel Antnio J. Almeida Nuno Vale 《International journal of molecular sciences》2022,23(15)
Cell-penetrating peptides (CPP) have been shown to be efficient in the transport of cargoes into the cells, namely siRNA and DNA, proteins and peptides, and in some cases, small therapeutics. These peptides have emerged as a solution to increase drug concentrations in different tissues and various cell types, therefore having a relevant therapeutic relevance which led to clinical trials. One of them, MAP, is a model amphipathic peptide with an α-helical conformation and both hydrophilic and hydrophobic residues in opposite sides of the helix. It is composed of a mixture of alanines, leucines, and lysines (KLALKLALKALKAALKLA). The CPP MAP has the ability to translocate oligonucleotides, peptides and small proteins. However, taking advantage of its unique properties, in recent years innovative concepts were developed, such as in silico studies of modelling with receptors, coupling and repurposing drugs in the central nervous system and oncology, or involving the construction of dual-drug delivery systems using nanoparticles. In addition to designs of MAP-linked vehicles and strategies to achieve highly effective yet less toxic chemotherapy, this review will be focused on unique molecular structure and how it determines its cellular activity, and also intends to address the most recent and frankly motivating issues for the future. 相似文献
64.
65.
Joo C. C. Ferreira Sara Granja Ana F. Almeida Ftima Baltazar M. Sameiro T. Gonalves Ana Preto Maria Joo Sousa 《International journal of molecular sciences》2023,24(1)
Colorectal cancer (CRC) has been ranked as one of the cancer types with a higher incidence and one of the most mortal. There are limited therapies available for CRC, which urges the finding of intracellular targets and the discovery of new drugs for innovative therapeutic approaches. In addition to the limited number of effective anticancer agents approved for use in humans, CRC resistance and secondary effects stemming from classical chemotherapy remain a major clinical problem, reinforcing the need for the development of novel drugs. In the recent years, the phenoxazines derivatives, Nile Blue analogues, have been shown to possess anticancer activity, which has created interest in exploring the potential of these compounds as anticancer drugs. In this context, we have synthetized and evaluated the anticancer activity of different benzo[a]phenoxazine derivatives for CRC therapy. Our results revealed that one particular compound, BaP1, displayed promising anticancer activity against CRC cells. We found that BaP1 is selective for CRC cells and reduces cell proliferation, cell survival, and cell migration. We observed that the compound is associated with reactive oxygen species (ROS) generation, accumulates in the lysosomes, and leads to lysosomal membrane permeabilization, cytosolic acidification, and apoptotic cell death. In vivo results using a chicken embryo choriollantoic membrane (CAM) assay showed that BaP1 inhibits tumor growth, angiogenesis, and tumor proliferation. These observations highlight that BaP1 as a very interesting agent to disturb and counteract the important roles of lysosomes in cancer and suggests BaP1 as a promising candidate to be exploited as new anticancer lysosomal-targeted agent, which uses lysosome membrane permeabilization (LMP) as a therapeutic approach in CRC. 相似文献
66.
67.
Factors influencing the national distribution of polycyclic aromatic hydrocarbons and polychlorinated biphenyls in British soils 总被引:5,自引:0,他引:5
Heywood E Wright J Wienburg CL Black HI Long SM Osborn D Spurgeon DJ 《Environmental science & technology》2006,40(24):7629-7635
The polycyclic aromatic hydrocarbons (PAHs) naphthalene, acenaphthylene, acenaphthene, fluorene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, ideno[1,2,3,-cd]-pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene and the polychlorinated biphenyls (PCBs) 8, 18, 28, 29, 31, 52, 77, 101, 105, 114, 118, 123, 126, 128, 138, 141, 149, 153, 156, 157, 163, 169, 170, 171, 180, 183, 187, 189, 194, 199, 201, 206, and 209 were measured in -200 rural soils across Great Britain (GB). Dominance of soil PAH profiles by heavier compounds (4-6 rings) provided initial evidence for the importance of source in governing soil PAH concentrations. No relationship was found between soil organic matter (SOM) and sum concentration of total and "heavy" PAHs, although there was a weak positive relationship with lighter compounds. A spatial statistical technique showed that highest soil PAH concentrations were usually found close to industrial/urban centers where presumably source intensity is highest. PCBs clustered into seven groups, five of which contained a single "dioxin like" PCB, one contained lighter congeners (2-4 chlorines), and one contained heavy congeners (5-10 chlorines). Linear regressions with SOM explained up to 24.3% of variation for the sum concentration of penta- to deca- congeners, but <1% for the lighter congener groups. No significant relationships were found with latitude. Spatial statistical techniques showed clusters of high soil PCB concentrations predominantly in west and south east GB, either associated with urbanized areas or on the West coast. 相似文献
68.
Phenol‐enriched olive oils modify paraoxonase‐related variables: A randomized,crossover, controlled trial 下载免费PDF全文
69.
Sara C. Cunha José O. Fernandes Isabel M. Ferreira 《European Food Research and Technology》2002,214(1):67-71
A reversed phase HPLC method for separation and determination of organic acids in fruit juices and nectars is presented. The method is based on the reaction of free organic acids with O-(4 nitrobenzyl)-N,N'-diisopropylisourea (PNBDI) in presence of dioxane. Excess of reagent was removed with a strong cation-exchange resin. The p-nitrobenzyl esters were separated on a C18 reversed phase column using gradient elution with water and acetonitrile and UV detection at 265 nm. Benzylmalonic acid was used as internal standard. The determinations were performed in the linear range of 0.05-2 g/l for lactic, acetic and succinic acids, 0.1-12 g/l for tartaric, malic and citric acids. The detection limits were 0.025 g/l, 0.017 g/l, 0.050 g/l, 0.039 g/l, 0.025 g/l and 0.060 g/l, respectively for lactic, acetic, tartaric, malic, succinic and citric acids. Validation of the method was carried out by the standard additions method, the recoveries ranged from 91.4 to 103.0%. The precision of the method was also evaluated and reported a CV% as less than 3.1%. Organic acid profiles of citrus fruit, pineapple and apple natural juices (home-made), commercial juices and nectars were established. 相似文献
70.
Sara Lombardo Gaetano Pandino Giovanni Mauromicale Matthias Knödler Reinhold Carle Andreas Schieber 《Food chemistry》2010
Globe artichoke is an ancient herbaceous plant native to the Mediterranean Basin. The edible part of the plant (head) is particularly rich in polyphenols, whose therapeutic properties are well documented. A field experiment was conducted in Sicily (south Italy) to examine the influence of genotype and harvest time on the polyphenol content and profile of different head parts. The concentrations of 19 phenolic compounds were determined by HPLC-DAD-ESI/MSn analysis. It was observed that individual phenolic substances were preferentially accumulated in specific head parts and genotypes. Apigenin 7-O-glucuronide was found to be the major flavonoid, with 6298 mg kg−1 DM in ‘Romanesco clone C3’ receptacle, whereas chlorogenic acid represented the main caffeoylquinic acid, reaching 14841 mg kg−1 DM in the inner bracts of ‘Violetto di Sicilia’. Our findings prove also the influence of climatic conditions on the phenolic profile and thus suggest giving specific consideration to harvest time. 相似文献