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981.
Ilaria De Pasquale Raffaella Di Cagno Solange Buchin Maria De Angelis Marco Gobbetti 《Applied and environmental microbiology》2014,80(19):6243-6255
Pyrosequencing of the 16S rRNA targeting RNA, community-level physiological profiles made with Biolog EcoPlates, proteolysis, and volatile component (VOC) analyses were mainly used to characterize the manufacture and ripening of the pasta filata cheese Caciocavallo Pugliese. Plate counts revealed that cheese manufacture affected the microbial ecology. The results agreed with those from culture-independent approaches. As shown by urea-PAGE, reverse-phase high pressure liquid chromatography (RP-HPLC), and free-amino-acid (FAA) analyses, the extent of secondary proteolysis mainly increased after 30 to 45 days of ripening. VOCs and volatile free fatty acids (VFFA) were identified by a purge-and-trap method (PT) and solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS), respectively. Except for aldehydes, the levels of most of VOCs and VFFA mainly increased from 30 to 45 days onwards. As shown through pyrosequencing analysis, raw cows'' milk was contaminated by Firmicutes (53%), Proteobacteria (39%), Bacteroidetes (7.8%), Actinobacteria (0.06%), and Fusobacteria (0.03%), with heterogeneity at the genus level. The primary starter Streptococcus thermophilus dominated the curd population. Other genera occurred at low incidence or sporadically. The microbial dynamics reflected on the overall physiological diversity. At 30 days, a microbial succession was clearly highlighted. The relative abundance of Streptococcus sp. and especially St. thermophilus decreased, while that of Lactobacillus casei, Lactobacillus sp., and especially Lactobacillus paracasei increased consistently. Despite the lower relative abundance compared to St. thermophilus, mesophilic lactobacilli were the only organisms positively correlated with the concentration of FAAs, area of hydrophilic peptide peaks, and several VOCs (e.g., alcohols, ketones, esters and all furans). This study showed that a core microbiota was naturally selected during middle ripening, which seemed to be the main factor responsible for cheese ripening. 相似文献
982.
983.
Raffaella Preziosi Tamagnini 《Plant biosystems》2013,147(3):187-193
Abstract Free beta-indoleacetic acid content in shoots of « Vicia sativa » seedlings grown in different environmental conditions. I. Seedlings grown in the dark and in the light. — Free IAA has been determined in shoots of Vicia sativa seedlings grown in the dark and in the light. The alcohol extract of the vegetable material has been submitted to several processes of purification (changes of PH and washing-out in ether, and successively column as well as thin layer chromatography). Lastly the IAA eluted with alcohol from the chromatographic slides is spectrometrically determined (λ = 280 mμ). The data show that the free IAA is contained to a greater extent in the seedlings grown in the dark in comparison to those grown in the light; this difference permaining in the samples of the same age as well as in those of the same height. The obtained data have been submitted to statistical analysis and both assays have shown to be highly significative. 相似文献
984.
Raffaella Soleti Chiara Porro Maria Carmen Martínez 《Apoptosis : an international journal on programmed cell death》2013,18(9):1029-1038
Cystic fibrosis (CF) is a recessively inherited disease caused by genetic lesions in CF transmembrane conductance regulator (CFTR) gene. CF is characterized by exaggerated inflammation, progressive tissue damage, and chronic bacterial colonization, mainly in the respiratory tract. The mechanisms underlying these pathological changes are increasingly well understood. However, apoptotic dysfunction in CF disease is still debated since studies report controversial results. Nonetheless, it is clear that apoptosis participates to onset of pathology and concerns various types of cells with variable susceptibility. Apoptosis is a physiological process necessary for the preservation of homeostasis of epithelial organization and function for clearance of inflammatory cells. Increased susceptibility to apoptosis in epithelial cells and failed apoptosis in neutrophils would contribute to the self-perpetuating inflammatory cycle in CF. Also, retention of mutated CFTR in the endoplasmic reticulum participates to inflammation which may trigger apoptosis. Independently of the sensibility to apoptosis of CF cells, it has been shown that clearance of apoptotic cells, due in part to decrease in efferocytosis, is flawed and that accumulation of such cells may contribute to ongoing inflammation in CF patients. Despite great advance in understanding CF pathophysiology, there is still no cure for the disease. The most recent therapeutic strategies are directed to target CFTR protein using cell and gene therapy as well as pharmacotherapy. 相似文献
985.
Simboli Alberto Taddeo Raffaella Raggi Andrea 《The International Journal of Life Cycle Assessment》2019,24(7):1285-1296
The International Journal of Life Cycle Assessment - This article analyses, in an industrial ecology (IE) perspective, urban contexts with specific features, such as a reduced space scale, a hybrid... 相似文献
986.
Raffaella Isola Paola Solinas Carolina Concettoni Francesca Atzeni Francesco Loy Martina Diana Michela Isola Gilberta Giacchetti Marco Boscaro Alessandro Riva Stefano Mariotti 《Cell and tissue research》2013,351(3):409-417
We compared changes in the morphology of mitochondrial cristae with those in the blood and adrenal content of steroid hormones after the stimulation or inhibition of steroidogenesis. Rats were treated with adrenocorticotrophic hormone or angiotensin II to elicit steroidogenesis and with dexamethasone to inhibit it. Blood and adrenal glands were collected after several time intervals for measurements of steroids and their main intermediates. In the zona fasciculata, mitochondrial ultrastructure was investigated by high resolution scanning electron microscopy. We found that the morphometric data correlated well with the measurements of hyper- or hypo-activity of steroidogenesis over short periods of time (4 h) but not over longer observation times. A peculiar finding was that, contrary to previous reports, 11-deoxycortisol was present in adult rat adrenal tissue. 相似文献
987.
Luisa Zupin Egidio Barbi Raffaella Sagredini Giulia Ottaviani Sergio Crovella Fulvio Celsi 《Journal of biophotonics》2021,14(2):e202000347
The analgesic properties of photobiomodulation therapy (PBMT) have been raising increasing interest in the clinical community due to the positive effects observed on patients, nevertheless the mechanistic basis of its action on peripheral sensory neurons remains still elusive. In this study, the effect of near-infrared (NIR) PBMT at 800 and 970 nm of wavelength was investigated on the 50B11 immortalized nociceptive sensory neuronal cell line by evaluating capsaicin-induced calcium flow and different markers correlated to mitochondria, that is, ATP, reactive oxygen species (ROS), and mitochondrial membrane potential (MMP). Calcium peak stimulated by capsaicin, the ligand of TRPV1 channel, was decreased in neurons pre-irradiated with the combination of the two wavelengths. Furthermore, delivering the 800 and 970 nm separately an increment of ATP, as well as MMP hyperpolarization were detected; notably, the 800 nm wavelength also increased ROS and O2− levels. Our findings, obtained on an in vitro model of nociception, show the positive effect of PBMT on two potential photo-targets of NIR light, namely the TRPV1 channel and the mitochondria. 相似文献
988.
989.
Raffaella Villa Francesco Molinari Monica Levati Fabrizio Aragozzini 《Biotechnology letters》1998,20(12):1105-1108
Eighteen species of plant cell could reduce of 2-pentanone, acetophenone and ethyl acetoacetate to the S-alcohols with yields ranging from 20 to 100 % (w/w) and optical purity ranging from 65 to 99 % enantiomeric excess (e.e.). © Rapid Science Ltd. 1998 相似文献
990.
Francesco Vizzari Martin Massnyi Nikola Kníatov Carlo Corino Raffaella Rossi
ubomír Ondruka Filip Tirpk Marko Halo Peter Massnyi 《Saudi Journal of Biological Sciences》2021,28(1):1017
Feed additive consisting of polysaccharides from brown seaweeds plus phenolic acid, hydroxycinnamic acids, tannins, and flavonoids from plant extracts, was used as rabbit food supplement. Main aim of the study was to determine the effect of natural mix of marine and freshwater seaweed polyphenols on selected reproductive characteristics of male rabbits during the 90-days experiment. Natural mix was incorporated in feed-pellets for rabbits in two different concentrations – 0.3% (T1 group) and 0.6% (T2 group), compared with a control group (C group). In experimental groups a significant increase of concentration of calcium during first 30 days of supplementation was found. An increase of alanine aminotransferase, glutathione peroxidase and ferric reducing ability of plasma and a decrease in aspartate aminotransferase after 90 days were recorded in the same groups. Except for that we noticed decrease of semen distance of curved line and velocity of curved line after 30 days though only while being supplemented with 0.6% proportion of seaweed polyphenols in feed mixture. Based on the results it can be stated that the natural mix in the tested levels do not show adverse effect on male rabbit reproductive parameters, and an improvement of antioxidant status was observed. The feed additives can have a very important effect on growth, health and development of animals in general as it supplies the with the much-needed minerals, nutritional substances and antioxidants, on which we focused in our study. 相似文献