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排序方式: 共有1370条查询结果,搜索用时 15 毫秒
61.
Francesco Borgia Lucia Peterle Paolo Custurone Mario Vaccaro Giovanni Pioggia Sebastiano Gangemi 《International journal of molecular sciences》2022,23(6)
Acne Vulgaris (AV) and Hidradenitis suppurativa (HS) are common chronic inflammatory skin conditions that affect the follicular units that often coexist or are involved in differential diagnoses. Inflammation in both these diseases may result from shared pathways, which may partially explain their frequent coexistence. MicroRNAs (miRNAs) are a class of endogenous, short, non-protein coding, gene-silencing or promoting RNAs that may promote various inflammatory diseases. This narrative review investigates the current knowledge regarding miRNAs and their link to AV and HS. The aim is to examine the role of these molecules in the pathogenesis of AV and HS and to identify possible common miRNAs that could explain the similar characteristics of these two diseases. Five miRNA (miR-155 miR-223-, miR-21, and miRNA-146a) levels were found to be altered in both HS and AV. These miRNAs are related to pathogenetic aspects common to both pathologies, such as the regulation of the innate immune response, regulation of the Th1/Th17 axis, and fibrosis processes that induce scar formation. This review provides a starting point for further studies aimed at investigating the role of miRNAs in AV and HS for their possible use as diagnostic-therapeutic targets. 相似文献
62.
Advances in Bioapplications of Carbon Nanotubes 总被引:1,自引:0,他引:1
Fushen Lu Lingrong Gu Mohammed J. Meziani Xin Wang Pengju G. Luo Lucia Monica Veca Li Cao Ya‐Ping Sun 《Advanced materials (Deerfield Beach, Fla.)》2009,21(2):139-152
This progress report provides an overview on recent advances in bioapplications of carbon nanotubes including the chemical modification of carbon nanotubes, targeting specifically their covalent and noncovalent conjugations with a variety of biological and bioactive species (proteins and peptides, DNAs/RNAs, and carbohydrates). Furthermore, the significant recent development and progress in the use of carbon nanotubes for biosensors, drug and other delivery systems, bioimaging, etc. and in the understanding of in vivo biodistribution and toxicity of carbon nanotubes are reported. 相似文献
63.
Jack A. Neal Betsy Booren Luis Cisneros-Zevallos Rhonda K. Miller Lisa M. Lucia Joseph E. Maxim Alejandro Castillo 《Journal of food science》2010,75(6):S319-S326
Abstract: The use of ionizing radiation for the control of foodborne pathogens and extending the shelf life of fresh iceberg lettuce and fresh spinach has recently been approved by the U.S. Food and Drug Administration. The efficacy of electron beam irradiation for controlling foodborne pathogens has been reported. For this experiment, the effectiveness of electron beam irradiation on the microbiological and sensory characteristics of fresh spinach was studied. Total aerobic plate counts were reduced by 2.6 and 3.2 log CFU/g at 0.7 and 1.4 kGy, respectively. Lactic acid bacteria were reduced at both doses of e-beam but grew slowly over the 35 d of the experiment. Yeasts and molds were not reduced in samples exposed to 0.7 kGy whereas 1.4 kGy significantly reduced microbial counts. Gas compositions (O2 and CO2) were significantly different than controls. Oxygen levels inside the spinach sample bags decreased over time; however, O2 levels did not drop below 1% that can induce anaerobic fermentation. CO2 levels for all treatments increased through day 4; yet 7 d after irradiation, CO2 level differences were not significant in both control and irradiated samples. Irradiation dose did not affect the basic tastes, aromatics, or mouth feels of fresh spinach, however; hardness attributes decreased as irradiated dose increased and slimy attributes of fresh spinach were higher in control samples compared to irradiated samples. 相似文献
64.
Lucia D’Urzo Benedetto Bozzini 《Journal of Materials Science: Materials in Electronics》2009,20(7):666-670
In this paper we investigate the corrosive behaviour of various volatile organic compounds (VOCs) on electroplated copper.
The VOCs we considered were of the following types: (i) aromatic and substituted-aromatic compounds (benzene, toluene and
ethyl benzene); (ii) a chlorine-substituted hydrocarbon (dichloromethane) and (iii) an aliphatic alcohol (isopropyl alcohol).
Contamination by VOCs is typical of ULSI (Ultra Large Scale Integration) manufacturing environments, and exposure of Cu to
VOC-contaminated clean room air has been pinpointed as a serious cause of interconnects failure. SEM observation highlighted
corrosion signature that are typical of the different classes of molecules. In particular, the corrosion of copper is almost
absent following exposure to isopropyl alcohol, very slow in the case of aromatic molecules and severe in the case of dichloromethane.
The obtained results can be interpreted in terms of a crevice corrosion mechanism under droplets, enhanced by pitting in the
presence of chlorinated solvents. 相似文献
65.
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67.
T Plant growth and morphogenesis depend on the levels and distribution of the plant hormone auxin. Plants tightly regulate cellular levels of the active auxin indole-3-acetic acid (IAA) through synthesis, inactivation, and transport. Although the transporters that move IAA into and out of cells are well characterized and play important roles in development, little is known about the transport of IAA precursors. In this review, we discuss the accumulating evidence suggesting that the IAA precursor indole-3-butyric acid (IBA) is transported independently of the characterized IAA transport machinery along with the recent identification of specific IBA efflux carriers and enzymes suggested to metabolize IBA. These studies have revealed important roles for IBA in maintaining IAA levels and distribution within the plant to support normal development. 相似文献
68.
Rosalba Lanciotti Milena Sinigaglia Fausto Gardini Lucia Vannini Maria Elisabetta Guerzoni 《Food microbiology》2001,18(6):659
This study focuses its attention on the boundary between the growth and no growth of three strains ofSalmonella enteritidis , Bacillus cereus and Staphylococcus aureus in the presence of growth controlling factors such as temperature, pH, water activity (Aw) and ethanol concentration. Preliminarly, the minimal values of pH, Awand temperature, and the maximum ethanol concentrations allowing the growth of the considered micro-organisms were determined. The calculation of these values enabled the use of logistic model to evaluate the growth/no growth boundary for the bacteria in relation to the considered independent variables. The location of the growth/no-growth boundaries for S. enteritidis and Staph. aureus were strongly affected, at the same ethanol concentration, by temperature, pH and Aw. Among the considered species, Staph. aureus was endowed with the highest sensitivity to low pH values whileB. cereus's growth/no growth interface, was quite unaffected by the combination of the stresses, when the physico–chemical conditions were above the minimum for growth. The effects of temperature, Awand ethanol on the limitation of growth of the considered species were not merely additive. It was possible to identify the combinations of such factors preventing the growth of Salmonella enteritidis, Staph. aureus and B. cereus. 相似文献
69.
Strains of Clostridium butyricum that produce botulinal toxin type E have been implicated in outbreaks of foodborne botulism in China, India, and Italy, yet the conditions that are favorable for the growth and toxinogenesis of these strains remain to be established. We attempted to determine the temperatures and pH levels that are most conducive to the growth of and toxin production by the six strains of neurotoxigenic C. butyricum that have been implicated in outbreaks of infective and foodborne botulism in Italy. The strains were cultured for 180 days on Trypticase-peptone-glucose-yeast extract broth at various pHs (4.6, 4.8, 5.0, 5.2, 5.4, 5.6, and 5.8) at 30 degrees C and at various temperatures (10, 12, and 15 degrees C) at pH 7.0. Growth was determined by checking for turbidity; toxin production was determined by the mouse bioassay. We also inoculated two foods: mascarpone cheese incubated at 25 and 15 degrees C and pesto sauce incubated at 25 degrees C. The lowest pH at which growth and toxin production occurred was 4.8 at 43 and 44 days of incubation, respectively. The lowest temperature at which growth and toxin production occurred was 12 degrees C, with growth and toxin production first being observed after 15 days. For both foods, toxin production was observed after 5 days at 25 degrees C. Since the strains did not show particularly psychrotrophic behavior, 4 degrees C can be considered a sufficiently low temperature for the inhibition of growth. However, the observation of toxin production in foods at room temperature and at abused refrigeration temperatures demands that these strains be considered a new risk for the food industry. 相似文献
70.
The mean linking number () of the topoisomer equilibrium distribution obtained upon relaxation of DNA minicircles with topoisomerase I did not increase linearly, but rather in a step wise fashion, with DNA size between 351 and 366 bp. As a consequence, the corresponding linking number difference () did not remain equal to 0, but rather oscillated between +/-0.3 with the periodicity of the double helix. This oscillation, not observed with plasmid-size DNA, is an expected consequence of the stiffness of short DNA. When minicircles were reconstituted with a nucleosome, the associated oscillated between approximately -1.4 +/-0. 2. This oscillation appears to result from the combined effects of DNA stiffness, and nucleosome ability to thermally fluctuate between three distinct DNA conformational states. Two of these states, a closed approximately 1.75-turn DNA conformation with negatively crossed entering and exiting DNAs, and an open approximately 1.4-turn conformation with uncrossed DNAs, are well known, whereas the third state, with a closed DNA conformation and DNAs tending to cross positively rather than negatively, is less familiar. Access to both closed "negative" and "positive" states appears to be mediated by histone N-terminal tails, as shown by specific alterations to the oscillation caused by histone acetylation and phosphate ions, a potent tail destabilizator. These results extend previous observations of ethidium bromide fluorescence titration in the accompanying article, which have pointed to an histone tail-dependent flexibility of entering and exiting DNAs to positive crossing. They also show that DNA wrapping around the histones occurred without twist alteration compared to the DNA free in solution, and reveal an intriguing new facet of the "linking-number-paradox" problem: the possibility for linkers in chromatin to adopt different crossing status within an overall dynamic equilibrium which may be regulated by histone acetylation. 相似文献