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排序方式: 共有598条查询结果,搜索用时 0 毫秒
591.
Marta Zar Jeness Campodonico Nicola Cosentino Maria Luisa Biondi Patrizia Amadio Gloria Milanesi Emilio Assanelli Silvia Cerri Marco Biggiogera Leonardo Sandrini Calogero Claudio Tedesco Fabrizio Veglia Daniela Trabattoni Fabio Blandini Elena Tremoli Giancarlo Marenzi Silvia S. Barbieri 《International journal of molecular sciences》2021,22(15)
The identification of new biomarkers allowing an early and more accurate characterization of patients with ST-segment elevation myocardial infarction (STEMI) is still needed, and exosomes represent an attractive diagnostic tool in this context. However, the characterization of their protein cargo in relation to cardiovascular clinical manifestation is still lacking. To this end, 35 STEMI patients (17 experiencing resuscitated out-of-hospital cardiac arrest (OHCA-STEMI) and 18 uncomplicated) and 32 patients with chronic coronary syndrome (CCS) were enrolled. Plasma exosomes were characterized by the nanoparticle tracking analysis and Western blotting. Exosomes from STEMI patients displayed a higher concentration and size and a greater expression of platelet (GPIIb) and vascular endothelial (VE-cadherin) markers, but a similar amount of cardiac troponin compared to CCS. In addition, a difference in exosome expression of acute-phase proteins (ceruloplasmin, transthyretin and fibronectin) between STEMI and CCS patients was found. GPIIb and brain-associated marker PLP1 accurately discriminated between OHCA and uncomplicated STEMI. In conclusion, the exosome profile of STEMI patients has peculiar features that differentiate it from that of CCS patients, reflecting the pathophysiological mechanisms involved in STEMI. Additionally, the exosome expression of brain- and platelet-specific markers might allow the identification of patients experiencing ischemic brain injury in STEMI. 相似文献
592.
Angela Di Pinto Elisabetta Bonerba Giancarlo Bozzo Edmondo Ceci Valentina Terio Giuseppina Tantillo 《European Food Research and Technology》2013,237(2):275-279
Considering that powdered infant milk formula effectively supports the growth of numerous pathogens, this study investigates the prevalence of potentially pathogenic Bacillus cereus in dried milk products by evaluating the occurrence of B. cereus and the presence of virulence-associated genes. The approach consisted of enriching, isolating and biochemical identifying isolates, followed by PCR assays aimed at the hbl (C, D, A, B), nhe (A, B, C) and cytK enterotoxin genes coding HBL complex, NHE complex and cytotoxin K, respectively. Among cytK-positive strains, the discrimination of two different forms for cytotoxin K, cytK-1 and cytK-2 was performed. Bacillus cereus was detected in powdered infant milk formula samples. All the strains harbored at least one gene of the cytK, HBL and NHE enterotoxins. Because of an increasing trend in invasive infections by B. cereus in infants and immunocompromised children, our PCR findings highlight the need to implement an adequate control plan in order to guarantee the health of potentially fragile consumers. From a hygiene point of view, intensive and continuous monitoring of potentially pathogenic B. cereus may be crucial for powdered infant milk formula safety and even recommended in order to assess the infant health risk, as proposed by Commission Regulation (EC) no. 1441/2007 on microbiological criteria for foodstuffs. Furthermore, the detection in this study of B. licheniformis, B. subtilis and B. mycoides strains raises significant health issues regarding Bacillus spp. in powdered infant milk formula. 相似文献
593.
Federica Menichini Rosa Tundis Marco Bonesi Monica R. Loizzo Filomena Conforti Giancarlo Statti Bruno De Cindio Peter J. Houghton Francesco Menichini 《Food chemistry》2009
During the past decade, it has been reported that the consumption of certain foods and spices such as pepper may have a positive effect on health. The present study evaluates the influence of fruit ripening on total phenols, flavonoids, carotenoids and capsaicinoids content and antioxidant, hypoglycaemic and anticholinesterase activities of Capsicum chinense Jacq. cv Habanero. The chemical investigation showed a different composition between the two stages of ripening (immature and mature). Generally, the concentration of carotenoids and capsaicinoids increased as the peppers reached maturity, whereas the concentration of phenols declined. The immature fruits showed the highest radical scavenging activity (IC50 of 97.14 μg/ml). On the contrary, the antioxidant activity evaluated by the β-carotene bleaching test showed a significant activity for mature peppers (IC50 value of 4.57 μg/ml after 30 min of incubation). Mature peppers inhibited α-amylase with an IC50 of 130.67 μg/ml. The lipophilic fractions of both mature and immature peppers exhibited an interesting and selective inhibitory activity against α-amylase with IC50 values of 29.58 and 9.88 μg/ml, respectively. Both total extracts of mature and immature peppers inhibited butyrylcholinesterase selectively. The obtained results underline the potential health benefits as a result of consuming C. chinense Habanero and suggest that it could be used as new valuable flavour with functional properties for food or nutriceutical products on the basis of the high content of phytochemicals and found biological properties. 相似文献
594.
Roberta Piacentini Laura Centi Mattia Miotto Edoardo Milanetti Lorenzo Di Rienzo Martina Pitea Paolo Piazza Giancarlo Ruocco Alberto Boffi Giacomo Parisi 《International journal of molecular sciences》2022,23(10)
The present investigation focuses on the analysis of the interactions among human lactoferrin (LF), SARS-CoV-2 receptor-binding domain (RBD) and human angiotensin-converting enzyme 2 (ACE2) receptor in order to assess possible mutual interactions that could provide a molecular basis of the reported preventative effect of lactoferrin against CoV-2 infection. In particular, kinetic and thermodynamic parameters for the pairwise interactions among the three proteins were measured via two independent techniques, biolayer interferometry and latex nanoparticle-enhanced turbidimetry. The results obtained clearly indicate that LF is able to bind the ACE2 receptor ectodomain with significantly high affinity, whereas no binding to the RBD was observed up to the maximum “physiological” lactoferrin concentration range. Lactoferrin, above 1 µM concentration, thus appears to directly interfere with RBD–ACE2 binding, bringing about a measurable, up to 300-fold increase of the KD value relative to RBD–ACE2 complex formation. 相似文献
595.
Isabella Medeiros Araújo Pedro Capalbo Becalette Elda Sabino da Silva Giancarlo de Souza Dias Michelle da Cunha Abreu Xavier Alex Fernando de Almeida Alfredo Eduardo Maiorano Sergio Andres Villalba Morales Rafael Firmani Perna 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2023,98(2):419-430
596.
Learned Indexes use a model to restrict the search of a sorted table to a smaller interval. Typically, a final binary search is done using the lower_bound routine of the Standard C++ library. Recent studies have shown that on current processors other search approaches (such as k-ary search) can be more efficient in some applications. Using the SOSD learned indexing benchmarking software, we extend these results to show that k-ary search is indeed a better choice when using learned indexes. We highlight how such a choice may be dependent on the computer architecture used, for example, Intel I7 or Apple M1, and provide guidelines for the selection of the Search routine within the learned indexing framework. 相似文献
597.
Paul Herrmann Sebastian Klimmer Thomas Lettau Mohammad Monfared Isabelle Staude Ioannis Paradisanos Ulf Peschel Giancarlo Soavi 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(37):2301126
With conventional electronics reaching performance and size boundaries, all-optical processes have emerged as ideal building blocks for high speed and low power consumption devices. A promising approach in this direction is provided by valleytronics in atomically thin semiconductors, where light-matter interaction allows to write, store, and read binary information into the two energetically degenerate but non-equivalent valleys. Here, nonlinear valleytronics in monolayer WSe2 is investigated and show that an individual ultrashort pulse with a photon energy tuned to half of the optical band-gap can be used to simultaneously excite (by coherent optical Stark shift) and detect (by a rotation in the polarization of the emitted second harmonic) the valley population. 相似文献
598.
Angelo G. Giumanini Giancarlo Verardo Sabina Cauci 《Advanced Synthesis \u0026amp; Catalysis》1987,329(3):417-432
Some aliphatic carboxylic anhydrides gave excellent yields of the novel addition products to both aliphatic and aromatic N-methyleneimines, starting from their aliphatic and aromatic trimeric cyclic oligomers. A preliminary positive ion mass spectrometric study is here reported. They hydrolyze surprisingly faster than the corresponding acid amides, making necessary the intervention of a special mechanism. The reduction of the acetylamideester of cyclohexylmethyleneimine ( 3c ) with LiAlH4 was also “abnormal”, as it yielded N-methyl-N-ethylcyclohexylamine in quantitative yield. 相似文献