排序方式: 共有5条查询结果,搜索用时 0 毫秒
1
1.
E. Giovenale M. D'Arienzo A. Doria G.P. Gallerano A. Lai G. Messina D. Piccinelli 《Journal of biological physics》2003,29(2-3):159-170
A compact THz Free Electron Laser (FEL) isbeing used to perform irradiation ofbiological samples to investigate possiblegenotoxic effects. In order to evaluate theexact radiation dose absorbed by the singlecomponents of the samples it is necessaryto study the optical properties of thesamples, separating the contributions tothe radiation attenuation coefficientcoming from absorption and from diffusion.Spectroscopic measurements have beenperformed on different biological samples, comparing the experimental results withtheoretical models. 相似文献
2.
Ramundo-Orlando A Gallerano GP Stano P Doria A Giovenale E Messina G Cappelli M D'Arienzo M Spassovsky I 《Bioelectromagnetics》2007,28(8):587-598
The effects of pulsed 130 GHz radiations on lipid membrane permeability were investigated by using cationic liposomes containing dipalmitoyl phosphatidylcholine (DPPC), cholesterol, and stearylamine. Carbonic anhydrase (CA) was loaded inside the liposomes and the substrate p-nitrophenyl acetate (p-NPA) added in the bulk aqueous phase. Upon permeation across the lipid bilayer, the trapped CA catalyzes the conversion of the p-NPA molecules into products. Because the self-diffusion rate of p-NPA across intact liposomes is very low the CA reaction rate, expressed as Delta A/min, is used to track membrane permeability changes. The effect of 130 GHz radiation pulse-modulated at low frequencies of 5, 7, or 10 Hz, and at time-averaged incident intensity (I(AV)) up to 17 mW/cm(2) was studied at room temperature (22 degrees C), below the phase transition temperature of DPPC liposomes. At all the tested values of I(AV) a significant enhancement of the enzyme reaction rate in CA-loaded liposomes occurred when the pulse repetition rate was 7 Hz. Typically, an increase from Delta A/min = 0.0026 +/- 0.0010 (n = 11) to Delta A/min = 0.0045 +/- 0.0013 (n = 12) (P < 0.0005) resulted at I(AV) = 7.7 mW/cm(2). The effect of 130 GHz pulse-modulated at 7 Hz was also observed on cationic liposomes formed with palmitoyloleoyl phosphatidylcholine (POPC), at room temperature (22 degrees C), above the phase transition temperature of POPC liposomes. 相似文献
3.
Gallerano Daniela Devanaboyina Siva Charan Swoboda Ines Linhart Birgit Mittermann Irene Keller Walter Valenta Rudolf 《Amino acids》2011,40(3):981-989
HIV-1 virus infectivity factor (Vif) is one of the four accessory proteins that are characteristic of primate lentiviruses
and critically required for the infection of host cells. Vif plays a key role in replication and transmission of the virus
in non-permissive cells, such as primary T cells and macrophages. Using co-precipitation and co-fractionation techniques,
evidence has been provided that Vif interacts with a variety of host proteins, such as the cytidine deaminases APOBEC3G and
3F, the Cullin5/EloBC ubiquitin–ligase complex, Fyn and Hck tyrosine kinases, as well as with viral components, such as the
immature Gag precursor and viral RNA. We report on the expression, purification and molecular characterization of a folded
recombinant subtype C Vif. Vif was expressed in E. coli with a C-terminal hexahistidine tag and purified by nickel affinity chromatography. We obtained approximately 5 mg protein
per liter of bacterial culture, with a purity >95%. The expected molecular mass of 23.7 kDa was confirmed by mass spectrometry.
Although dynamic light scattering and small angle X-ray scattering measurements revealed the presence of high molecular weight
aggregates in the protein preparation, circular dichroism analysis showed that the protein contains mainly folded β-sheet
elements and exhibits remarkable thermal stability (T
m > 95°C). Recombinant Vif may be used as a tool to study its biological functions and tertiary structure, as well as for the
development of diagnostic, therapeutic and preventive strategies for HIV-1 infections. 相似文献
4.
5.
M.R. ScarfÌ M. RomanÒ R. Di Pietro O. Zeni A. Doria G.P. Gallerano E. Giovenale G. Messina A. Lai G. Campurra D. Coniglio M. D'Arienzo 《Journal of biological physics》2003,29(2-3):171-176
The aim of the present study is toinvestigate the genotoxic effect of THzradiation in human peripheral bloodlymphocytes following 20 minutes exposureto 1 mW average power Free Electron Laserradiation in the frequency range 120–140GHz. For this purpose 9 healthy donors wereemployed and cytokinesis block techniquewas applied to study micronucleusfrequency and cell proliferation. Theresults obtained indicate that all theelectromagnetic conditions adopted so far do not alter the investigated parameters,suggesting absence of direct chromosomaldamage and alteration of cell cyclekinetics (two tailed paired Student's test:p>
0.05 in all cases). 相似文献
1