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1.
Neurol Sci ; 36 Suppl 1: 145-7, 2015 May.
Article in English | MEDLINE | ID: mdl-26017531

ABSTRACT

Migraine is a primary headache characterized by recurrent attacks of head pain associated with nausea or vomit, photophobia, phonophobia and osmophobia. The presence of osmophobia during migraine attacks seems to be a very specific complaint. Cutaneous allodynia (CA) is very common in migraineurs, and it is the most evident clinical manifestation of central sensitization, a mechanism involved in migraine chronification. This study was aimed at identifying the possible correlation between osmophobia and CA in migraineurs. 673 migraineurs were studied (492 episodic, 181 chronic). The prevalence of both CA and osmophobia was higher in chronic than in episodic migraineurs. The association between these two symptoms was significant in chronic migraineurs at Chi square test. The highlighted relationship between CA and osmophobia may be interpreted in different ways: central sensitization induced by recurrent pain stimulation may in parallel induce a distortion of both cutaneous sensitivity (CA) and olfaction (osmophobia); alternatively, the recurrent olfactory stimulation in subjects with a hypersensitivity to olfactory stimuli may co-work with repetitive pain stimulation to induce the central sensitization process.


Subject(s)
Central Nervous System Sensitization/physiology , Migraine Disorders/complications , Phobic Disorders/etiology , Smell/physiology , Adult , Female , Humans , Male , Middle Aged , Phobic Disorders/epidemiology , Skin/innervation
2.
J Nanosci Nanotechnol ; 15(12): 10074-90, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26682454

ABSTRACT

Mankind faces several global challenges such as chronic and acute hunger, global poverty, energy deficiency and environment conservation. Common biotechnologies based on batch, fluidbed and other similar processes are now extensively used for the production of a wide range of products such as antibiotics, biofuels, cultured and fermented food products. Unfortunately, these processes suffer from low efficiency, high energy demand, low controllability and rapid biocatalyst degradation by microbiological attack, and thus still are not capable of seriously addressing the global hunger and energy deficiency challenges. Moreover, sustainable future technologies require minimizing the environmental impact of toxic by-products by implementing the "life produces organic matter, organic matter sustains life" principle. Nanostructure-based biotechnology is one of the most promising approaches that can help to solve these challenges. In this work we briefly review the unique features of the carbon-based nanostructured platforms, with some attention paid to other nanomaterials. We discuss the main building blocks and processes to design and fabricate novel platforms, with a focus on dense arrays of the vertically-aligned nanostructures, mainly carbon nanotubes and graphene. Advantages and disadvantages of these systems are considered.


Subject(s)
Bioreactors , Biotechnology , Nanotubes, Carbon , Nanostructures
3.
Nanotechnology ; 24(24): 245604, 2013 Jun 21.
Article in English | MEDLINE | ID: mdl-23696315

ABSTRACT

Plasma-induced non-equilibrium liquid chemistry is used to synthesize gold nanoparticles (AuNPs) without using any reducing or capping agents. The morphology and optical properties of the synthesized AuNPs are characterized by transmission electron microscopy (TEM) and ultraviolet-visible spectroscopy. Plasma processing parameters affect the particle shape and size and the rate of the AuNP synthesis process. Particles of different shapes (e.g. spherical, triangular, hexagonal, pentagonal, etc) are synthesized in aqueous solutions. In particular, the size of the AuNPs can be tuned from 5 nm to several hundred nanometres by varying the initial gold precursor (HAuCl4) concentration from 2.5 µM to 1 mM. In order to reveal details of the basic plasma-liquid interactions that lead to AuNP synthesis, we have measured the solution pH, conductivity and hydrogen peroxide (H2O2) concentration of the liquid after plasma processing, and conclude that H2O2 plays the role of the reducing agent which converts Au(+3) ions to Au(0) atoms, leading to nucleation growth of the AuNPs.

5.
Nat Commun ; 9(1): 879, 2018 02 28.
Article in English | MEDLINE | ID: mdl-29491411

ABSTRACT

Drastic miniaturization of electronics and ingression of next-generation nanomaterials into space technology have provoked a renaissance in interplanetary flights and near-Earth space exploration using small unmanned satellites and systems. As the next stage, the NASA's 2015 Nanotechnology Roadmap initiative called for new design paradigms that integrate nanotechnology and conceptually new materials to build advanced, deep-space-capable, adaptive spacecraft. This review examines the cutting edge and discusses the opportunities for integration of nanomaterials into the most advanced types of electric propulsion devices that take advantage of their unique features and boost their efficiency and service life. Finally, we propose a concept of an adaptive thruster.

6.
Nat Commun ; 9(1): 1464, 2018 04 10.
Article in English | MEDLINE | ID: mdl-29636453

ABSTRACT

The original PDF version of this Article had an incorrect volume number of '8'; it should have been '9'. This has been corrected in the PDF version of the Article. The HTML version was correct from the time of publication.

7.
Nanoscale ; 8(12): 6623-8, 2016 Mar 28.
Article in English | MEDLINE | ID: mdl-26939617

ABSTRACT

Device grade silicon nanocrystals (NCs) are synthesized using an atmospheric-pressure plasma technique. The Si NCs have a small and well defined size of about 2.3 nm. The synthesis system allows for the direct creation of thin films, enabling a range of measurements to be performed and easy implementation of this material in different devices. The chemical stability of the Si NCs is evaluated, showing relatively long-term durability thanks to hydrogen surface terminations. Optical and electrical characterization techniques, including Kelvin probe, ultraviolet photoemission spectroscopy and Mott-Schottky analysis, are employed to determine the energy band diagram of the Si NCs.

8.
Biochim Biophys Acta ; 475(1): 96-102, 1977 Mar 02.
Article in English | MEDLINE | ID: mdl-849450

ABSTRACT

The accuracy and the efficiency of the protein synthesis machinery has been measured by the variability of the [3H]leucine/[14C]phenylalanine ratio in a cell-free protein synthesis system, poly(U) directed, and with the same criteria by binding aminoacyl tRNA-ribosome complexes with poly(U). Using these two methods, we have observed the aging of rats to be characterized by an increase of 3H/14C ratios according to the "general error theory". The results obtained are discussed in relation to the redundancy and rectification of the genes involved in the protein synthesis machinery formation.


Subject(s)
Liver/metabolism , Protein Biosynthesis , Ribosomes/metabolism , Aging , Animals , Carbon Radioisotopes , Isotope Labeling , Kinetics , Leucine/metabolism , Liver/growth & development , Phenylalanine/metabolism , Poly U , Rats , Tritium
9.
Nanoscale ; 7(27): 11566-74, 2015 Jul 21.
Article in English | MEDLINE | ID: mdl-26084561

ABSTRACT

Silicon nanocrystal (Si-nc) down-conversion is demonstrated to enhance organic and hybrid organic/inorganic bulk heterojunction solar cells based on PTB7:[70]PCBM bulk heterojunction devices. Surfactant free surface-engineered Si-ncs can be integrated into the device architecture to be optically active and provide a means of effective down-conversion of blue photons (high energy photons below ∼450 nm) into red photons (above ∼680 nm) leading to 24% enhancement of the photocurrent under concentrated sunlight. We also demonstrate that the down-conversion effect under 1-sun is enhanced in the case of hybrid solar cells where engineered Si-ncs are also included in the active layer.

10.
Sci Rep ; 5: 17477, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-26621791

ABSTRACT

The synthesis feasibility of silicon-tin nanocrystals by discharges in liquid nitrogen is studied using a Si-10 at % Sn sintered electrode. Time-resolved optical emission spectroscopy shows that silicon and tin melt almost simultaneously. The presence of both vapours does not lead to the synthesis of alloyed nanocrystals but to the synthesis of separate nanocrystals of silicon and tin with average sizes of 10 nm. These nanocrystals are transformed into amorphous silicon oxide (am-SiO2) and ß-SnO2 by air oxidation, after evaporation of the liquid nitrogen. The synthesis of an am-Si0.95Sn0.05 phase around large silicon crystals (~500 nm) decorated by ß-Sn spheroids is achieved if the current flowing through electrodes is high enough. When the sintered electrode is hit by powerful discharges, some grains are heated and tin diffuses in the large silicon crystals. Next, these grains are shelled and fall into the dielectric liquid.

11.
Plant Cell Rep ; 16(10): 725-730, 1997 Jul.
Article in English | MEDLINE | ID: mdl-30727627

ABSTRACT

Hairy roots were obtained after infection of Artemisia absinthium shoots with Agrobacterium rhizogenes strains 1855 and LBA 9402. The susceptibility to hairy root transformation varied between plant genotypes and bacterial strains. Hairy roots showed macroscopic differences from control root cultures. Southern blot hybridization confirmed the integration of T-DNA from both p1855 and pBin19, while polymerase chain reaction analysis indicated the presence of the neomycin phosphotransferase gene in the hairy root genome. Subcultured transformed root lines grew well in selective B5 agar-solidified medium containing kanamycin or rifampicin and without hormones. Shake-flask experiments with fast-growing root lines showed that 40 g l-1 was the best sucrose concentration for biomass production, yielding a 463-fold increase in dry weight after 28 days of culture. Great differences were found in the profiles of the essential oils isolated from normal and hairy roots. Gas chromatography/mass spectrometry analysis showed the oil produced by transformed cultures to be a mixture of 50 compounds with only one major component representing 37% of the oil content.

12.
Minerva Med ; 89(5): 181-3, 1998 May.
Article in Italian | MEDLINE | ID: mdl-9676185

ABSTRACT

A clinical case of a young adult 23-years old is reported. The concomitant presence of tetanic symptoms and the anamnestic finding of a spider bite has made impossible a differential diagnosis of the pathology. The therapeutic approach, consisting in antibiotics and analgesics, is also reported. The administration of "antivenin" has not proven decisive to the resolution of the clinical picture. The diagnostic doubt has however represented a poorly influencing factor for a correct therapy.


Subject(s)
Spider Bites/diagnosis , Tetanus/diagnosis , Adult , Analgesics, Opioid/therapeutic use , Arm , Buprenorphine/therapeutic use , Diagnosis, Differential , Follow-Up Studies , Humans , Male , Muscular Diseases/drug therapy , Muscular Diseases/etiology , Spasm/drug therapy , Spasm/etiology , Spider Bites/drug therapy , Time Factors , Tramadol/therapeutic use
13.
EDTNA ERCA J ; 24(3): 36-7, 1998.
Article in English | MEDLINE | ID: mdl-10392078

ABSTRACT

Haemodialysis patients are at high risk of developing liver disease due to blood-borne viral agents. At present hepatitis C virus (HCV) is the most common cause of infection in these patients. A new RNA virus of the Flaviviridae family, hepatitis G virus (HGV) has recently been cloned. HGV prevalence in haemodialysis patients ranges from 3.1% to 57.5%. The aim of this study has been to detect HGV-RNA in our haemodialysis patients in order to evaluate the prevalence of HGV and to correlate the viral presence to liver disease. A total of 79 patients, on haemodialysis for a mean of 52 months, were tested. 3 patients (3.8%) were HBsAG positive and 19 patients (24%) were HCV positive. 24 of the 79 (30%) patients had been transfused. Only 2 of the 79 patients (2.5%) were HGV positive. These patients were HBsAG and anti HCV negative, both had been previously transfused and showed no signs of liver disease.


Subject(s)
Flaviviridae , Hepatitis, Viral, Human/etiology , Infection Control/methods , Renal Dialysis/adverse effects , Aged , Female , Flaviviridae/genetics , Hepatitis, Viral, Human/blood , Hepatitis, Viral, Human/prevention & control , Humans , Male , Middle Aged , Prevalence , RNA, Viral/blood , Risk Factors
14.
Behav Neurol ; 2014: 919627, 2014.
Article in English | MEDLINE | ID: mdl-25049452

ABSTRACT

BACKGROUND: Migraineurs brain has shown some functional peculiarities that reflect not only in phonophobia, and photophobia, but also in mood and sleep. Dreaming is a universal mental state characterized by hallucinatory features in which imagery, emotion, motor skills, and memory are created de novo. We evaluated dream contents and associated emotions in migraineurs. MATERIALS AND METHODS: 412 subjects: 219 controls; and 148 migraineurs (66 with aura, MA; 82 without aura, MO), and 45 tension type headache patients (TTH). A semistructured retrospective self-reported questionnaire was used to evaluate dreams. The Generalized Anxiety Disorder Questionnaire (GAD-7), and the Patient Health Questionnaire (PHQ-9) were administered to evaluate anxiety and depression. RESULTS: Migraineurs showed increased levels of anxiety (P = 0.0002 for MA versus controls, P = 0.004 for MO versus controls). Fear and anguish during dreaming were more frequently reported by migraine patients compared to controls, independently by anxiety and depression scores. DISCUSSION: The brain of migraineurs seems to dream with some peculiar features, all with a negative connotation, as fear and anguish. It may be due to the recorded negative sensations induced by recurrent migraine pain, but it may just reflect a peculiar attitude of the mesolimbic structures of migraineurs brain, activated in both dreaming and migraine attacks.


Subject(s)
Anxiety/epidemiology , Dreams/psychology , Fear/psychology , Migraine Disorders/psychology , Stress, Psychological/epidemiology , Adult , Anxiety/psychology , Female , Humans , Male , Middle Aged , Prevalence , Retrospective Studies , Stress, Psychological/psychology , Young Adult
15.
Nanoscale ; 5(15): 6725-30, 2013 Aug 07.
Article in English | MEDLINE | ID: mdl-23783181

ABSTRACT

Here we demonstrate the material's synthetic feasibility for semiconducting alloyed silicon-tin nanocrystals (SiSn-NCs) with quantum confinement effects. An environmentally friendly synthesis is achieved by ns laser ablation of amorphous SiSn in water at ambient conditions. Plasmas generated in the liquid by laser pulses are characterized by spatial confinement with very high pressure (GPa), which allowed the growth of the SiSn-NCs via kinetic pathways. We further illustrate that surface engineering by a direct-current atmospheric pressure microplasma is capable of tailoring the SiSn-NCs surface properties without the need for lengthy surfactants, resulting in room temperature photoluminescence (PL); the PL peak wavelength is red-shifted by more than 250 nm with respect to the PL peak wavelengths observed for comparable elemental silicon nanocrystals.

18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(6 Pt 2): 065401, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20365224

ABSTRACT

Electrical characterization of a nonthermal radio-frequency atmospheric-pressure microplasma in a parallel plate configuration has shown that reducing electrode gap into the submillimeter range increases current and power density at a reduced voltage as compared to similar plasmas at larger electrode gaps which have no gap dependence. Calculation of sheath thickness and electric fields in the sheath and in the bulk demonstrate a dependence on the electrode gap as it is reduced into the submillimeter regime, indicating a distinct regime of operation.

19.
Chromosoma ; 63(1): 33-7, 1977 Aug 18.
Article in English | MEDLINE | ID: mdl-144048

ABSTRACT

The inhibition of DNA synthesis with hydroxyurea or 5-fluorode-oxyuridine decreases the duration of S-phase of synchronously growing Chinese hamster cultures. - The observed drug effects are discussed in relation to an alteration of programmed DNA replication.


Subject(s)
Mitosis/drug effects , Cells, Cultured , DNA Replication/drug effects , Floxuridine/pharmacology , Hydroxyurea/pharmacology , Time Factors
20.
Cell Biol Int Rep ; 8(4): 297-307, 1984 Apr.
Article in English | MEDLINE | ID: mdl-6733789

ABSTRACT

The equilibrium distribution of 5,5-dimethyloxazolidine-2,4-dione (DMO) between intra- and extracellular volume was used to estimate the intracellular pH in Yoshida rat ascites hepatoma AH-130 cells under different growth conditions (log, midlog and stationary). The cells were suspended in a Krebs-Ringer 25 mM phosphate buffer and the effects of variation of external pH, of glucose and amiloride addition on intracellular pH were measured. Proliferating cells had higher intracellular pH than stationary phase cells and this difference was inhibited by amiloride. On addition of glucose the fall in external pH was similar in all conditions and corresponded to lactate production. However, the intracellular pH decreased only in proliferating cells. Stationary phase cells showed an amiloride-sensitive cytoplasmic alkalinization with glucose. Glucose addition also caused prompt recovery to a normal polysomal pattern in these cells that might suggest increased efficiency of the initiation step of protein synthesis under these conditions. The data thus suggest that the increased intracellular pH of proliferating and of glucose-treated stationary phase cells is linked to the rate of protein synthesis and is mediated by the amiloride-sensitive Na+/H+ exchange system. This could lead to increased intracellular Na+ concentration under these conditions and to initiation of growth.


Subject(s)
Amiloride/pharmacology , Glucose/pharmacology , Liver Neoplasms, Experimental/metabolism , Pyrazines/pharmacology , Animals , Ascites/metabolism , Ascites/pathology , Cell Division/drug effects , Female , Hydrogen-Ion Concentration , Liver Neoplasms, Experimental/pathology , Rats , Rats, Inbred Strains
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