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361.
The reconstruction of shape and pose of a solid of revolution from a single image is addressed. When there is no cross section, whose contour can be extracted from the image, this problem is underdeterminate; therefore, a reflection from a point light source is used in addition to the contour information. Under the orthoperspective hypothesis, when axial-symmetric reflection model is applicable, the reflection appears along a meridian of the revolution surface. This fact is exploited in order to determine both the orientation of the revolution axis and the shape of the profile. Promising experimental results have been obtained. 相似文献
362.
DJ Loftus P Squarcina MB Nielsen C Geisler C Castelli N Odum E Appella G Parmiani L Rivoltini 《Canadian Metallurgical Quarterly》1998,58(11):2433-2439
The self-peptide MART1(27-35) derives from the melanocyte/melanoma protein Melan A/MART1 and is a target epitope of CD8+ T cells, commonly recovered from tumor-infiltrating lymphocytes of HLA-A2.1+ melanoma patients. Despite their prevalence in such patients, these CTLs generally appear to be ineffective in mediating tumor regression in vivo. We have noted previously that numerous peptides from both endogenous and foreign proteins are similar to MART1(27-35) and, potentially, are capable of productively engaging the T-cell receptors of patient-derived CTLs. This observation raised the question of whether CTLs in vivo might encounter self-peptide analogues of MART1(27-35) that lack full agonist activity, perhaps to the detriment of the antitumor CTL response. This possibility was evaluated using cloned, patient-derived CTLs with a panel of self-derived natural analogues of MART1(27-35) in assays for cytolysis, cytokine release, and phosphorylation of T-cell receptor signaling constituents. Several peptides were identified as partial agonists, capable of eliciting cytolysis and/or release of cytokines tumor necrosis factor-alpha and IFN-gamma but not interleukin 2. Several other peptides showed antagonist behavior, effectively inhibiting cytolysis of MART1(27-35)-pulsed targets, but did not inhibit killing of cells prepulsed with a synthetic, heteroclitic variant of MART1(27-35). Some of these antagonists also had lasting effects on interleukin 2 secretion by CTLs under experimental conditions involving sequential exposure to ligands. Together, these observations suggest that encounters with self-peptide analogues of MART1(27-35) may contribute to the peripheral maintenance of these CTLs, while ultimately impairing the efficacy of this antitumor T-cell response. 相似文献
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Francesca Malvano Donatella Albanese Roberto Pilloton Marisa Di Matteo Alessio Crescitelli 《Food and Bioprocess Technology》2017,10(10):1834-1843
Due to their increasing use in agriculture, the presence of pesticide residues in food and water currently represents one of the major issues for the food safety. Among the pesticides, organophosphate and carbamate species are the most used, and their toxicity is mainly due to their inhibitory effect on acetylcholinesterase (AChE). For this reason, a monoenzymatic acetylcholinesterase impedimetric biosensor was developed in order to sensitively detect carbamate and organophosphate compounds with a very fast response. The working principle of the AChE biosensor exploits the capability of carbamate and organophosphate pesticides to form a stable complex with the enzyme, which causes an impedimetric change. The impedimetric biosensor showed a linearity between 5 and 170 ppb for carbamates and 2.5–170 ppb for organophosphate compounds, with a reproducibility (RSD%) interelectrode equal to 4.8 and 3.1% for organophosphates and carbamates, respectively. Moreover, the common amperometric evaluation of AChE inhibition degree was correlated to the impedimetric changes of the electrode surface, showing a good correlation (R 2 = 0.99 for carbamates and R 2 = 0.98 for organophosphates) between the two methods. In contrast to amperometric evaluation that needs a response time of 20 min, impedimetric detection requires only 4 min. Finally, the impedimetric biosensor was used to measure carbaryl and dichlorvos spiked in different concentrations in tap water and lettuce samples, showing a recovery near to 100% for all concentrations and for both pesticides. 相似文献
365.
High Saturated Fat Diet Alters the Lipid Composition of Triacylglycerol and Polar Lipids in the Femur of Dam and Offspring Rats
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Paula M. Miotto Laura M. Castelli Foyinsola Amoye Wendy E. Ward Paul J. LeBlanc 《Lipids》2015,50(6):605-610
Previous work has shown that dietary lipids alter femur lipid composition. Specifically, we have shown that exposure to high saturated fatty acid (SFA) diets in utero, during suckling, or post‐weaning alters femur total lipid composition, resulting in higher percent bone mass in males and females and bone mineral density (BMD) in female offspring with no effect on bone mineral outcomes in dams. Comparatively, high n‐3 polyunsaturated fatty acid (PUFA) diets increase femur polar (PL) lipid n‐3 content, which has been associated with increased bone mineral content and strength. However, the extent that PL or triacylglycerol (TAG) lipids change with high SFA diets is unknown. The current investigation examined the influence of a high SFA diet (20 % lard by weight) on femur PL and TAG lipid composition in 5‐month old female Wistar rats (fed high SFA diet from age 28 days onwards; dams) and their 19‐day old offspring (exposed to high SFA in utero and during suckling; pups). High SFA exposure resulted in increased monounsaturates and decreased n‐3 and n‐6 PUFA in the TAG fraction in both dams and pups, and higher SFA and n‐6:n‐3 ratio in dams only. The PL fraction showed decreased n‐6 PUFA in both dams and pups. The magnitude of the diet‐mediated responses, specifically TAG 18:1 and PL n‐6 PUFA, may have contributed to the previously reported altered BMD, which was supported with correlation analysis. Future research should investigate the relationship of diet‐induced changes in bone lipids on bone structure, as quantified through micro‐computed tomography. 相似文献
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D. Pattono L.M. Battaglini A. Barberio L. De Castelli A. Valiani G. Varisco M.L. Scatassa P. Davit M. Pazzi T. Civera 《Food chemistry》2009
Samples of conventional (n = 11) and organic (n = 81) milk, both raw and heat-treated, were analysed for the presence of synthetic antioxidants (butylated hydroxytoluene, butylated hydroxyanisole, dodecyl gallate, propyl gallate and octyl gallate) to verify whether those labelled as “organic” corresponded to EU Regulations on the use of additives in such products. The analysis detected only the antioxidant BHT and its aldehyde BHT–CHO in all 11 conventional milk and in 18 of 81 organic milk samples. The investigation highlights the importance of strict control of organic dairy production, since synthetic antioxidants added to feedstuff to prevent rancidity can be transferred to milk. 相似文献
369.
Maria Dolci Lucia Signorini Sarah DAlessandro Federica Perego Silvia Parapini Michele Sommariva Donatella Taramelli Pasquale Ferrante Nicoletta Basilico Serena Delbue 《International journal of molecular sciences》2022,23(7)
In the novel pandemic of Coronavirus Disease 2019, high levels of pro-inflammatory cytokines lead to endothelial activation and dysfunction, promoting a pro-coagulative state, thrombotic events, and microvasculature injuries. The aim of the present work was to investigate the effect of SARS-CoV-2 on pro-inflammatory cytokines, tissue factor, and chemokine release, with Human Microvascular Endothelial Cells (HMEC-1). ACE2 receptor expression was evaluated by western blot analysis. SARS-CoV-2 infection was assessed by one-step RT-PCR until 7 days post-infection (p.i.), and by Transmission Electron Microscopy (TEM). IL-6, TNF-α, IL-8, IFN-α, and hTF mRNA expression levels were detected by RT-PCR, while cytokine release was evaluated by ELISA. HMEC-1 expressed ACE2 receptor and SARS-CoV-2 infection showed a constant viral load. TEM analysis showed virions localized in the cytoplasm. Expression of IL-6 at 24 h and IFN-α mRNA at 24 h and 48 h p.i. was higher in infected than uninfected HMEC-1 (p < 0.05). IL-6 levels were significantly higher in supernatants from infected HMEC-1 (p < 0.001) at 24 h, 48 h, and 72 h p.i., while IL-8 levels were significantly lower at 24 h p.i. (p < 0.001). These data indicate that in vitro microvascular endothelial cells are susceptible to SARS-CoV-2 infection but slightly contribute to viral amplification. However, SARS-CoV-2 infection might trigger the increase of pro-inflammatory mediators. 相似文献
370.
Giorgio Tiecco Samuele Storti Melania Degli Antoni Emanuele Foc Francesco Castelli Eugenia Quiros-Roldan 《International journal of molecular sciences》2022,23(4)
The Coronavirus disease 2019 (COVID-19) pandemic poses a great threat to global public health. The original wild-type strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has genetically evolved, and several variants of concern (VOC) have emerged. On 26 November 2021, a new variant named Omicron (B.1.1.529) was designated as the fifth VOC, revealing that SARS-CoV-2 has the potential to go beyond the available therapies. The high number of mutations harboured on the spike protein make Omicron highly transmissible, less responsive to several of the currently used drugs, as well as potentially able to escape immune protection elicited by both vaccines and previous infection. We reviewed the latest publication and the most recent available literature on the Omicron variant, enlightening both reasons for concern and high hopes for new therapeutic strategies. 相似文献