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941.
Francesco Caruso Virginia Sciacca Giorgio Bellia Emilio De Domenico Giuseppina Larosa Elena Papale Carmelo Pellegrino Sara Pulvirenti Giorgio Riccobene Francesco Simeone Fabrizio Speziale Salvatore Viola Gianni Pavan 《PloS one》2015,10(12)
The sperm whale (Physeter macrocephalus) emits a typical short acoustic signal, defined as a “click”, almost continuously while diving. It is produced in different time patterns to acoustically explore the environment and communicate with conspecifics. Each emitted click has a multi-pulse structure, resulting from the production of the sound within the sperm whale’s head. A Stable Inter Pulse Interval (Stable IPI) can be identified among the pulses that compose a single click. Applying specific algorithms, the measurement of this interval provides useful information to assess the total length of the animal recorded. In January 2005, a cabled hydrophone array was deployed at a depth of 2,100 m in the Central Mediterranean Sea, 25 km offshore Catania (Ionian Sea). The acoustic antenna, named OνDE (Ocean noise Detection Experiment), was in operation until November 2006. OνDE provided real time acoustic data used to perform Passive Acoustic Monitoring (PAM) of cetacean sound emissions. In this work, an innovative approach was applied to automatically measure the Stable IPI of the clicks, performing a cepstrum analysis to the energy (square amplitude) of the signals. About 2,100 five-minute recordings were processed to study the size distribution of the sperm whales detected during the OνDE long term deep-sea acoustic monitoring. Stable IPIs were measured in the range between 2.1 ms and 6.4 ms. The equations of Gordon (1991) and of Growcott (2011) were used to convert the IPIs into measures of size. The results revealed that the sperm whales recorded were distributed in length from about 7.5 m to 14 m. The size category most represented was from 9 m to 12 m (adult females or juvenile males) and specimens longer than 14 m (old males) seemed to be absent. 相似文献
942.
Phytochemical Analysis,Biological Activity,and Secretory Structures of Stachys annua (L.) L. subsp. annua (Lamiaceae) from Central Italy
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Alessandro Venditti Armandodoriano Bianco Luana Quassinti Massimo Bramucci Giulio Lupidi Silvia Damiano Fabrizio Papa Sauro Vittori Laura Maleci Bini Claudia Giuliani Domenico Lucarini Filippo Maggi 《化学与生物多样性》2015,12(8):1172-1183
Stachys annua subsp. annua, well‐known in central Italy as ‘stregona annuale’, is an annual, small, slightly‐scented herb, commonly found in fields and uncultivated areas in almost all regions of Italy. In folk medicine, its aerial parts were used as anti‐catarrhal, febrifuge, tonic, and vulnerary. In the present work, the chemical composition of the flowering aerial parts was studied. The hydrodistilled volatile oil, analysed by GC/MS, showed sesquiterpenoids as the major fraction (42.5%); phytol (9.8%), germacrene D (9.2%), and spathulenol (8.5%) were the most abundant constituents. The volatile oil was assayed for antioxidant and cytotoxic activity by DPPH, ABTS, FRAP, and MTT methods. The cytotoxicity results against HCT116, A375, and MDA‐MB 231 human tumor cell lines were significant, with IC50 values of 23.5, 37.2, and 41.5 μg/ml, respectively, whereas the antioxidant power was negligible. The EtOH extract was composed mainly of three glycosidic flavonoids, namely 7‐{[2‐O‐(6‐O‐acetyl‐β‐D ‐allopyranosyl)‐β‐D ‐glucopyranosyl]oxy}‐5,8‐dihydroxy‐2‐(4‐methoxyphenyl)‐4H‐1‐benzopyran‐4‐one ( 1 ), 7‐{[6‐O‐acetyl‐2‐O‐(6‐O‐acetyl‐β‐D ‐allopyranosyl)‐β‐D ‐glucopyranosyl]oxy}‐2‐(3,4‐dihydroxyphenyl)‐5,8‐dihydroxy‐4H‐1‐benzopyran‐4‐one ( 2 ), and 7‐{[6‐O‐acetyl‐2‐O‐(β‐D ‐allopyranosyl)‐β‐D ‐glucopyranosyl]oxy}‐2‐(3‐hydroxy‐4‐methoxyphenyl)‐5,8‐dihydroxy‐4H‐1‐benzopyran‐4‐one ( 3 ). On the contrary, iridoids, considered chemotaxonomic markers of the genus Stachys, were absent in this species. Finally, the morphological and histochemical survey showed that glandular trichomes were composed of two main types, i.e. peltate type A and capitate types B and C giving positive response for both lipids and polyphenols. 相似文献
943.
Massimiliano Migliori Vincenzo Cantaluppi Claudio Mannari Alberto A. E. Bertelli Davide Medica Alessandro Domenico Quercia Victor Navarro Alessia Scatena Luca Giovannini Luigi Biancone Vincenzo Panichi 《PloS one》2015,10(4)
Introduction
Several studies demonstrated that endothelium dependent vasodilatation is impaired in cardiovascular and chronic kidney diseases because of oxidant stress-induced nitric oxide availability reduction. The Mediterranean diet, which is characterized by food containing phenols, was correlated with a reduced incidence of cardiovascular diseases and delayed progression toward end stage chronic renal failure. Previous studies demonstrated that both red and white wine exert cardioprotective effects. In particular, wine contains Caffeic acid (CAF), an active component with known antioxidant activities.Aim of the study
The aim of the present study was to investigate the protective effect of low doses of CAF on oxidative stress-induced endothelial injury.Results
CAF increased basal as well as acetylcholine—induced NO release by a mechanism independent from eNOS expression and phosphorylation. In addition, low doses of CAF (100 nM and 1 μM) increased proliferation and angiogenesis and inhibited leukocyte adhesion and endothelial cell apoptosis induced by hypoxia or by the uremic toxins ADMA, p-cresyl sulfate and indoxyl sulfate. The biological effects exerted by CAF on endothelial cells may be at least in part ascribed to modulation of NO release and by decreased ROS production. In an experimental model of kidney ischemia-reperfusion injury in mice, CAF significantly decreased tubular cell apoptosis, intraluminal cast deposition and leukocyte infiltration.Conclusion
The results of the present study suggest that CAF, at very low dosages similar to those observed after moderate white wine consumption, may exert a protective effect on endothelial cell function by modulating NO release independently from eNOS expression and phosphorylation. CAF-induced NO modulation may limit cardiovascular and kidney disease progression associated with oxidative stress-mediated endothelial injury. 相似文献944.
Savini I Catani MV Arnone R Rossi A Frega G Del Principe D Avigliano L 《Free radical biology & medicine》2007,42(5):608-616
Reactive oxygen species (ROS) and redox state have emerged as physiological mediators, controlling blood coagulation and thrombosis. The redox balance is obviously linked to the presence of antioxidants; in particular, vitamin C appears to be a key modulator of platelet oxidative state, since these cells physiologically accumulate ascorbic acid and, moreover, platelet ascorbate plays a role during aggregation. Here, we showed that platelets could compensate for fluctuations in ascorbate levels by modulating the expression of the Na+-dependent transporter SVCT2. Furthermore, the use of anucleated cells demonstrated, for the first time, that SVCT2 expression could be regulated at the translational level. The control of ascorbic acid uptake, through regulation of its carrier, was not only related to substrate availability, but it also occurred during platelet activation, which was accompanied by vitamin C deprivation and alteration in the redox state. Finally, we showed that changes in intracellular ascorbic acid content had physiological relevance, since they modulate the surface sulfhydryl content and the thrombus viscoelastic properties. Beside its role during aggregation, vitamin C may also have important effects during postaggregatory events. 相似文献
945.
946.
947.
Alfredo Coppa Andrea Cucina Domenico Mancinelli Rita Vargiu James M. Calcagno 《American journal of physical anthropology》1998,107(4):371-386
Discrete and metric dental traits are used to assess biological similarities and differences among 13 bioarchaeological populations located on each side of the Apennine mountains in central-southern Italy and dated to the first millennium BC . An initial hypothesis, that the mountain chain might provide a significant geographical barrier for population movement (resulting in greater biological affinities among those groups on the same side), is not supported. Instead, the samples appear to cluster more on the basis of time than geography. Archaeological evidence, however, supports an association between populations on opposite sides of the mountains and thus is in accord with the dental data. As anticipated, discrete dental traits appear to be more useful than metric dental traits in assessing such population affinities. This research represents a beginning to a better comprehension of the complexity of the biological and cultural dynamics of Italian populations during recent millennia. Am J Phys Anthropol 107:371–386, 1998. © 1998 Wiley-Liss, Inc. 相似文献
948.
Domenico Salerno Claudia Adriana Marrano Valeria Cassina Matteo Cristofalo Qing Shao Laura Finzi Francesco Mantegazza David Dunlap 《Nucleic acids research》2021,49(20):11778
Single molecule experiments have demonstrated a progressive transition from a B- to an L-form helix as DNA is gently stretched and progressively unwound. The particular sequence of a DNA segment defines both base stacking and hydrogen bonding that affect the partitioning and conformations of the two phases. Naturally or artificially modified bases alter H-bonds and base stacking and DNA with diaminopurine (DAP) replacing adenine was synthesized to produce linear fragments with triply hydrogen-bonded DAP:T base pairs. Both unmodified and DAP-substituted DNA transitioned from a B- to an L-helix under physiological conditions of mild tension and unwinding. This transition avoids writhing and the ease of this transition may prevent cumbersome topological rearrangements in genomic DNA that would require topoisomerase activity to resolve. L-DNA displayed about tenfold lower persistence length than B-DNA. However, left-handed DAP-substituted DNA was twice as stiff as unmodified L-DNA. Unmodified DNA and DAP-substituted DNA have very distinct mechanical characteristics at physiological levels of negative supercoiling and tension. 相似文献
949.
Rocco Rossano Marilena Larocca Margherita Macellaro Domenico Bilancia Paolo Riccio 《Current issues in molecular biology》2022,44(1):105
Cancer metastasis is a stage of the disease where therapy is mostly ineffective; hence, the need to find reliable markers of its onset. The metalloproteinase-9 (MMP-9, gelatinase B) in its 82 kDa active form, is a good candidate, but here we show that the correspondent little known 65 kDa active MMP-9 isoform, often misrepresented with the other gelatinase MMP-2, is a more suitable marker. Sera from patients with lung and breast cancer were analyzed by bidimensional zymography to detect the activity of MMP-9 and MMP-2. Enzyme identity was confirmed by comparison with MMP-9 standards and by western blotting. The 65 kDa isoform of MMP-9 is a suitable biomarker to monitor tumor progression from tissue neoplasms to metastatic stage, as its activity begins to appear when disease severity increases and becomes very high in metastasis. Moreover, the 65 kDa MMP-9, which derives from the 82 kDa MMP-9, no longer responds to natural MMP-9 inhibitors. As its activity cannot be controlled, its appearance may warn that the pathological process is becoming irreversible. Identification and inhibition of the enzymes converting the inhibitor-sensitive 82 kDa MMP-9 into the corresponding “wild” 65 kDa MMP-9 may allow to develop therapies capable of blocking metastases. 相似文献
950.
Roberta Iatta Jairo Alfonso Mendoza-Roldan Maria Stefania Latrofa Antonio Cascio Emanuele Brianti Marco Pombi Simona Gabrielli Domenico Otranto 《PLoS neglected tropical diseases》2021,15(9)
Visceral leishmaniasis (VL) caused by Leishmania infantum is endemic in the Mediterranean basin with most of the infected human patients remaining asymptomatic. Recently, the saurian-associated Leishmania tarentolae was detected in human blood donors and in sheltered dogs. The circulation of L. infantum and L. tarentolae was investigated in humans, dogs and cats living in the Pelagie islands (Sicily, Italy) by multiple serological and molecular testing. Human serum samples (n = 346) were tested to assess the exposure to L. infantum by immunofluorescence antibody test (IFAT), enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) and to L. tarentolae by IFAT. Meanwhile, sera from dogs (n = 149) and cats (n = 32) were tested for both Leishmania species by IFAT and all blood samples, including those of humans, by specific sets of real time-PCR for L. infantum and L. tarentolae. The agreement between serological tests performed for human samples, and between serological and molecular diagnostic techniques for both human and animal samples were also assessed.Overall, 41 human samples (11.8%, 95% CI: 8.9–15.7) were positive to L. infantum (5.2%, 95% CI: 3.3–8.1), L. tarentolae (5.2%, 95% CI: 3.3–8.1) and to both species (1.4%, 95% CI: 0.6–3.3) by serology and/or molecular tests. A good agreement among the serological tests was determined. Both Leishmania spp. were serologically and/or molecularly detected in 39.6% dogs and 43.7% cats. In addition to L. infantum, also L. tarentolae circulates in human and animal populations, raising relevant public health implications. Further studies should investigate the potential beneficial effects of L. tarentolae in the protection against L. infantum infection. 相似文献