1,434 research outputs found
Lessons learnt from the Sgorigrad and Stava disasters
The catastrophic failures of tailings dams at Sgorigrad (Bulgaria) and Stava (Italy) are analyzed, pinpointing the many similarities of the two cases. A description is given about the shortcomings in the construction of these geotechnical structures and the causes of their collapse. Further information is provided about the lessons learnt from these disasters and the activities carried out to keep memory alive and qualify young engineers and geologists on the proper and safe management of tailings dams
First report on egg-parasitoids of the Asian planthopper Ricania speculum
The first findings of egg-parasitoids of the invasive planthopper Ricania speculum (Walker) (Hemiptera Ricaniidae) are presented.
Aprostocetus (Ootetrastichus) crino (Walker) (Hymenoptera Eulophidae), a native species until now only associated with Oecanthus
spp. (Orthoptera Oecanthidae) eggs, was the most common. Chaetostricha similis (Silvestri) (Hymenoptera Trichogrammatidae)
and Polynema sp. (Hymenoptera Mymaridae), which also emerged from R. speculum egg clusters, should be confirmed as
parasitoids of this planthopper
Antiepileptogenic effects of trilostane in the kainic acid model of temporal lobe epilepsy
Objective: Epileptogenesis after status epilepticus (SE) has a faster onset in rats treated to reduce brain levels of the anticonvulsant neurosteroid allopregnanolone with the 5α-reductase inhibitor finasteride; however, it still has to be evaluated whether treatments aimed at increasing allopregnanolone levels could result in the opposite effect of delaying epileptogenesis. This possibility could be tested using the peripherally active inhibitor of 3β-hydroxysteroid dehydrogenase/Δ5-4 isomerase trilostane, which has been shown repeatedly to increase allopregnanolone levels in the brain.
Methods: Trilostane (50 mg/kg) was administered subcutaneously once daily for
up to six consecutive days, starting 10 min after intraperitoneal administration of
kainic acid (15 mg/kg). Seizures were evaluated by video-electrocorticographic
recordings for 70 days maximum, and endogenous neurosteroid levels were
assessed by liquid chromatography–electrospray tandem mass spectrometry.
Immunohistochemical staining was performed to evaluate the presence of brain
lesions.
Results: Trilostane did not alter the latency of kainic acid-induced SE onset or its
overall duration. When compared to the vehicle-treated group, rats receiving six
daily trilostane injections presented a remarkable delay of the first spontaneous
electrocorticographic seizure and subsequent tonic–clonic spontaneous recurrent
seizures (SRSs). Conversely, rats treated with only the first trilostane injection
during SE did not differ from vehicle-treated rats in developing the SRSs.
Notably, trilostane did not modify neuronal cell densities or the overall damage
in the hippocampus. In comparison to the vehicle group, repeated administration
of trilostane significantly decreased the activated microglia morphology in
the subiculum. As expected, allopregnanolone and other neurosteroid levels were
remarkably increased in the hippocampus and neocortex of rats treated for 6 days
with trilostane, but pregnanolone was barely detectable. Neurosteroids returned
to basal levels after a week of trilostane washout..
Significance: Overall, these results suggest that trilostane led to a remarkable increase in allopregnanolone brain levels, which was associated with protracted effects on epileptogenesis
The European grape berry moth, Eupoecilia ambiguella (Lepidoptera: Tortricidae): Current knowledge and management challenges
The European grape berry moth, Eupoecilia ambiguella (Hübner) (Lepidoptera: Tortricidae), since its first identification in 1796, was defined as a key pest for European viticulture despite its polyphagy. Although between the
late 1800s and early 1900s its presence and spread in Europe was of concern, to date its populations are low and
limited to cooler and wetter areas, leading to a decline in its importance. In the present work, we reviewed its
global distribution as well as its morphology, biology, and ecology. Considering the monitoring and management
of this pest, the present review summarised insecticidal, agronomic, and cultural control strategies. Moreover,
given the need to reduce the impact of agriculture on the environment, humans, and non-target species, we
focused on control strategies relying on pheromones and biological control agents (e.g. predators and parasitoids) involved in conservation biological control
15 GHz quadrature voltage controlled oscillator in 130 nm CMOS technology
This paper reports a 15 GHz quadrature voltage controlled oscillator (QVCO) designed in a 130 nm CMOS technology. The phase noise performance of the QVCO and of a phase locked loop (PLL) where the QVCO was inserted were compared with the literature and with telecom standards and commercial products for broadcast satellite applications
The first record in Italy of Trichogramma cordubense Vargas & Cabello 1985 (Hymenoptera: Trichogrammatidae) emerging from the eggs of Lobesia botrana (Denis & Schiffermüller, 1775) (Lepidoptera: Tortricidae)
This study investigated the egg parasitoids of Lobesia botrana (Denis & Schiffermüller, 1775) feeding on Daphne gnidium L. (Malvales, Thymelaeaceae) in the San Rossore-Migliarino-Massaciuccoli Nature Reserve (Tuscany, Italy). Four species of egg parasitoids of the genus Trichogramma spp. were obtained. The parasitization rate gradually increased over the season, reaching its maximum level in September 2015, with a percentage of parasitized eggs close to 55 %. Three of the species obtained were already known as L. botrana parasitoids, whereas the finding of Trichogramma cordubense Vargas & Cabello, 1985 represents the first recording in Italy, as well as the first report of this species among the natural enemies of L. botrana
P2X7 mRNA expression in non-small cell lung cancer: MicroRNA regulation and prognostic value
The human P2X7 receptor is significant and exhibits several functions in neoplasia. At present, little is known with regard to its regulation. P2X7 expression may be regulated post-transcriptionally and putative microRNA (miRNA) binding sites are considered to be involved. The aim of this study was to determine whether miRNAs (miR-21, let-7 g and miR-205) regulate P2X7 mRNA stability. In addition, the impact of P2X7 expression in patients with non-small cell lung cancer (NSCLC) was investigated. P2X7 mRNA and mature Let-7 g, miR-21, and miR-205 expression levels were quantified in 96 NSCLC cases using quantitative reverse transcription polymerase chain reaction. In all samples, epidermal growth factor receptor and K-Ras mutational analysis was also performed. Samples with low P2X7 expression were found to exhibit a higher fold change in miR-21 expression when compared with samples exhibiting high P2X7 expression. Significantly higher miR-21 expression was observed in the tumors of NSCLC patients with a K-Ras mutation when compared with patients who had K-Ras wild-type tumors (P=0.003). Additionally, to evaluate the association between P2X7 expression and prognosis in NSCLC patients, survival analysis was performed using the Kaplan-Meier method. A significant difference in the progression-free survival and overall survival in the NSCLC patients with high P2X7 expression was identified, when compared with that of patients with low expression (P=0.03 and P=0.02, respetively). Therefore, we hypothesized that high levels of miR-21 expression in NSCLC patients with K-Ras mutations may be regulated by a complex circuit, including P2X7 downregulation and together these processes may promote tumor progression
Identification and synthesis of new sex-specific components of olive fruit fly (Bactrocera oleae) female rectal gland, through original Negishi reactions on supported catalysts
In the present study, eleven new sex-specific components extracted from female rectal gland of olive fruit flies were synthesized and identified. The quantitative determination of those components by GC and GC/EI-MS, at different moments of the insect life span, highlighted the growing trend of their secretion. While for the synthesis of saturated esters, conventional transesterification methods could be adopted, for the synthesis of unsaturated components, a Negishi cross-coupling between organozinc halides and (Z)-1-bromo-1-alkenes was developed. To the extent of our knowledge, this reaction represents the first example of supported-catalyst promoted Negishi coupling, between an alkylzinc reagent and an alkenyl halide
Investigation on the microbiological hazards in an artisanal salami produced in Northern Italy and its production environment in different seasonal periods
In the present study, the occurrence of Listeria monocytogenes, Staphylococcus aureus, Salmonella spp. and Escherichia coli VTEC was investigated in two batches of artisanal Italian salami tested in winter and summer. Moreover, enumerations of total bacterial count, lactic acid bacteria and Enterobacteriaceae were performed as well as monitoring of water activity and pH. Samples were taken from raw materials, production process environment, semi-finished product and finished products. The results revealed an overall increase of total bacterial count and lactic acid bacteria during the ripening period, along with a decrease of Enterobacteriaceae, pH and water activity. No significant difference was observed between the two batches. The enterobacterial load appeared to decrease during the maturation period mainly due to a decrease in pH and water activity below the limits that allow the growth of these bacteria. E. coli VTEC, Salmonella spp. or L. monocytogenes were not detected in both winter and summer batches. However, Klebsiella pneumoniae was detected in both summer and winter products. Except for one isolate, no biological hazards were detected in the finished salami, proving the efficacy of the ripening period in controlling the occurrence of microbiological hazard in ripened salami. Further studies are required to assess the virulence potential of the Klebsiella pneumoniae isolates
Augmentation of endogenous neurosteroid synthesis alters experimental status epilepticus dynamics
Neurosteroids can modulate γ-aminobutyric acid type A receptor-mediated inhibitory
currents. Recently, we discovered that the neurosteroids progesterone,
5α-dihydroprogesterone, allopregnanolone, and pregnanolone are reduced in the cerebrospinal
fluid of patients with status epilepticus (SE). However, it is undetermined
whether neurosteroids influence SE. For this reason, first we evaluated whether the
inhibitor of adrenocortical steroid production trilostane (50 mg/kg) could modify the
levels of neurosteroids in the hippocampus and neocortex, and we found a remarkable
increase in pregnenolone, progesterone, 5α-dihydroprogesterone, and allopregnanolone
levels using liquid chromatography tandem mass spectrometry. Second, we
characterized the dynamics of SE in the presence of the varied neurosteroidal milieu
by a single intraperitoneal kainic acid (KA; 15 mg/kg) injection in trilostane-treated
rats and their controls. Convulsions started in advance in the trilostane group, already
appearing 90 minutes after the KA injection. In contrast to controls, convulsions
prevalently developed as generalized seizures with loss of posture in the trilostane
group. However, this effect was transient, and convulsions waned 2 hours before the
control group. Moreover, electrocorticographic traces of convulsions were shorter
in trilostane-treated rats, especially at the 180-minute (P < .001) and 210-minute
(P < .01) time points. These findings indicate that endogenous neurosteroids remarkably
modulate SE dynamics
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