1,514 research outputs found
Comparison of the TaqMan and LightCycler systems in pharmacogenetic testing: evaluation of the CYP2C9*2/*3 polymorphisms.
Background: Pharmacogenetic testing for drugmetabolizing enzymes is not yet widely used in clinical practice. Methods: In an attempt to facilitate the application of this procedure, we have compared two real-time PCRbased methods, the TaqMan_ and the LightCycler_ for the pharmacogenetic evaluation of CYP2C9*2/*3 polymorphisms. Results and Conclusion: Both procedures are suitable for pharmacogenetic studies. The TaqMan procedure was less expensive in terms of cost per sample, but the TaqMan apparatus is more expensive than the LightCycler apparatus
Lotta alla mosca delle olive in olivicoltura integrata e biologica
Bactrocera oleae, fitofago chiave dell’agroecosistema olivo, è presente in Italia in tutti gli areali interessati dalla coltura, tranne in alcune aree caratterizzate da maggiore altitudine dove il fattore termico non consente lo sviluppo della specie. Il dittero è fortemente legato alle temperature che del resto condizionano anche la fenologia dell’olivo; in effetti il numero di generazioni che la mosca può completare nell’anno varia da 1 fino a 4-5 in zone con temperature medie annue elevate (zone costiere e/o meridionali). La pericolosità della specie è pertanto legata al numero di generazioni e all’andamento climatico che, a seconda dell’annata e della zona, possono variare sensibilmente condizionando la densità di popolazione e quindi il grado di dannosità potenziale del fitofago. Recenti ricerche sul comportamento e sulla biologia del tefritide hanno messo in evidenza come il fitofago, nel tempo, abbia contratto con i batteri una simbiosi mutualistica che permette al dittero di aumentare il proprio potenziale biotico. Nel presente articolo, dopo un breve excursus sulla biologia e sui danni causati dal fitofago, viene fatto il quadro delle attuali strategie di lotta ammesse nei protocolli dell’olivicoltura integrata e biologica.The control of the olive fruit fly in integrated and organic olive crops. Bactrocera oleae (Rossi) is the key pest of the olive agroecosystem; it is distributed in all Italian olive crops, except in some areas at higher altitude where low temperatures do not allow the development of the fly. The olive fruit fly development is strictly affected by temperature. It can complete from one up to five generations per year in areas with high annual average temperature (coastal and/ or southern areas). The harmfulness of the species is related to the number of generations and weather conditions which may fluctuate considerably year by year, region by region. Recent researches on behavior and natural history of the tephritid fly have pointed out that it has developed a mutualistic symbiosis with bacteria which allows an increase of its growth rate. In this article authors present control strategies permitted in integrated and organic olive crops.
The currently widespread early harvesting and timely milling reduce the harmful influence of late olive fruit fly infestations; together with mass trapping and with repellent/ oviposition deterrent sprays by copper products and clays, these practices allow an increasingly sustainable effective
control of the olive fruit fl
The mtDNA 15497 G/A polymorphism in cytochrome b in severe obese subjects from Southern Italy.
Background and aim: A large number of mitochondrial DNA (mtDNA)
mutations have been implicated in degenerative diseases and aging. The aim of this
study was to evaluate whether the 15497 G/A mtDNA polymorphism (G251S) in the
cytochrome b subunit of respiratory complex III, which has been associated with
obesity-related variables and lipid metabolism in a Japanese population, is
associated with severe obesity also in adult Caucasians from southern Italy.
Methods and results: Unrelated severely obese patients (n Z 317; BMI > 40 kg/m2)
and controls (n Z 217; BMI < 25 kg/m2) from Southern Italy were genotyped by
allelic discrimination TaqMan assay for the 15497 G/A mtDNA polymorphism. In
obese patients fasting serum total cholesterol, triglycerides, HDL-cholesterol and
glucose were measured enzymatically and sitting blood pressure and heart rate
were also collected. Mean levels of total cholesterol, triglycerides and glucose were
below the upper reference limit for healthy subjects. Female obese subjects
showed lower levels of blood pressure and heart rate and higher levels of
HDL cholesterol than male obese patients (P < 0.001). All the control subjects and 315/317 severely obese patients were homozygous for the G allele (wild type),
whereas only 2/317, were females homozygous for the A allele.
Conclusions: The mtDNA 15497 G/A polymorphism in cytochrome b was present in
0.6% obese subjects, two females whose lipid parameters and BMI were similar to
those of the overall group. Therefore, this mutation may appear to contribute in
rare instances to severe obesity but does not explain the majority of cases in our
population. A more extensive genetic haplogroup characterization is required to
identify associations to obesity in Caucasians
Effect of quasi-bound states on coherent electron transport in twisted nanowires
Quantum transmission spectra of a twisted electron waveguide expose the
coupling between traveling and quasi-bound states. Through a direct numerical
solution of the open-boundary Schr\"odinger equation we single out the effects
of the twist and show how the presence of a localized state leads to a
Breit-Wigner or a Fano resonance in the transmission. We also find that the
energy of quasi-bound states is increased by the twist, in spite of the
constant section area along the waveguide. While the mixing of different
transmission channels is expected to reduce the conductance, the shift of
localized levels into the traveling-states energy range can reduce their
detrimental effects on coherent transport.Comment: 8 pages, 9 color figures, submitte
Pressure-tuning of the electron-phonon coupling: the insulator to metal transition in manganites
A comprehensive understanding of the physical origin of the unique magnetic
and transport properties of A_(1-x)A'^xMnO_3 manganites (A = trivalent
rare-earth and A' = divalent alkali-earth metal) is still far from being
achieved. The complexity of these systems arises from the interplay among
several competing interactions of comparable strength. Recently the
electron-phonon coupling, triggered by a Jahn-Teller distortion of the MnO_6
octahedra, has been recognised to play an essential role in the insulator to
metal transition and in the closely related colossal magneto-resistance. The
pressure tuning of the octahedral distortion gives a unique possibility to
separate the basic interactions and, at least in principle, to follow the
progressive transformation of a manganite from an intermediate towards a weak
electron-phonon coupling regime. Using a diamond anvil cell, temperature and
pressure-dependent infrared absorption spectra of La_(0.75)Ca_(0.25)MnO_3 have
been collected and, from the spectral weight analysis, the pressure dependence
of the insulator to metal transition temperature T_IM has been determined for
the first time up to 11.2 GPa. The T_IM(P) curve we proposed to model the
present data revealed a universality character in accounting for the whole
class of intermediate coupling compounds. This property can be exploited to
distinguish the intermediate from the weak coupling compounds pointing out the
fundamental differences between the two coupling regimes.Comment: 8 pages, 4 figure
Tuning topological disorder in MgB
We carried out Raman measurements on neutron-irradiated and Al-doped MgB
samples. The irradiation-induced topological disorder causes an unexpected
appearance of high frequency spectral structures, similar to those observed in
lightly Al-doped samples. Our results show that disorder-induced violations of
the selection rules are responsible for the modification of the Raman spectrum
in both irradiated and Al-doped samples. Theoretical calculations of the phonon
density of states support this hypothesis, and demonstrate that the high
frequency structures arise mostly from contributions at of the
E phonon mode.Comment: 4 pages, 4 figure
High pressure Raman study of La1-xCaxMnO3-δ manganites
We report a high-pressure Raman study on two members of the La1-xCaxMnO3-δ manganite family (x = 0.20, δ = 0 and δ = 0.08). The results obtained for the δ = 0 sample show a different behavior in the low and high pressure regime which is ascribed to the onset of a new pressure-activated interaction previously invoked in other manganite compounds. The comparison of our results with literature data gives further support to the identification of the Jahn-Teller sensitive stretching mode and shows that pressure-induced octahedral symmetrization is more effective in systems exhibiting a lower metallic character. On the contrary the new interaction sets in at a pressure which decreases on increasing the metallic character of the system indicating an important role of the Mn-Mn hopping integral in its activatio
High pressure Raman study of LaCaMnO manganites
We report on a high-pressure Raman study on two members of the
LaCaMnO manganite family (, and
). The results obtained for the sample show a different
behavior in the low and high pressure regimes ascribed to the onset of a new
pressure-activated interaction previously invoked in other manganite compounds.
The comparison of our results with literature data gives further support to the
identification of the Jahn-Teller active stretching mode and shows that
pressure-induced octahedral symmetrization is more effective in systems
exhibiting a lower metallic character. On the contrary the new interaction sets
in at pressure which decreases on increasing the metallic character of the
system indicating a relevant role of the Mn-Mn hopping integral in its
activation.Comment: 4 pages, 3 figure, submitted to Phys. Rev.
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