Infiltrazione macrofagica e densità capillare nel carcinoma della laringe. Studio su 52 casi

L’angiogenesi è uno dei sei principali meccanismi alla base del cancro, ed è stato studiato approfonditamente negli ultimi 20 anni. L’obiettivo del presente studio è stato quello di determinare sia la densità capillare sia l’infiltrato macrofagico nei campioni di carcinoma laringeo e di determinarne la correlazione con gli aspetti clinici e patologici. Sia la densità capillare (CD34) sia l’infiltrato macrofagico (CD68) sono stati determinati con metodiche immunoistochimiche mediante microarray. Il nostro campione ha mostrato una densità capillare media di 14,27 ± 12,92 vasi su campo ingrandito a 200×, e l’infiltrato macrofagico medio è stato di 5,19 ± 4,32. La densità capillare si è dimostrata superiore nei pazienti metastatici. Inoltre uno studio di regressione lineare ha mostrato che l’entità dell’infiltrato macrofagico poteva predire la densità capillare del campione di carcinoma laringeo preso in esame. Non abbiamo invece individuato una correlazione fra ambo i fattori studiati e l’incidenza delle recidive o gli altri fattori clinici presi in esame. Il nostro studio aggiunge dati ad un problema che per quanto studiato a fondo negli ultimi 20 anni resta nella sostanza controverso

Nanodiamond Emitters of Single Photons

Luminescence properties of single color centers were studied in nanodiamonds of different origin. It was found that single photon emitters could be realized even in molecularsized diamond (less than 2 nm) capable of housing stable luminescent center “silicon-vacancy.” First results on incorporation of single-photon emitters based on luminescent nanodiamonds in plasmonic nanoantennas to enhance the photon count rate and directionality, diminish the fluorescence decay time, and provide polarization selectivity are presented

PULSED LASER PLASMOTRONS

No abstract availabl

Growth of diamond films on laser-treated substrates

Polycrystalline diamond films (DF) grown from hydrocarbons at low pressures is highly attractive material for optical, mechanical, electronic and other applications, in which the unique physical and chemical properties of diamond are used. Fabrication of diamond-based electronic devices requires a high resolution patterning of DF, however a conventional post-growth processing (polishing, etching ...) is difficult because of extreme hardness and chemical inertness of diamond. We report on alternative method to produce fine structures in DF - selected-area diamond deposition on laser-irradiated substrates. CVD diamond films have polycrystalline structure because the film growth is initiated independently on selected nucleation sites randomly distributed over substrate surface. The diamond nucleation sites were artificially created on polished Si wafer by seeding the ultrafine (5 nm) diamond powder using ultrasonic pre-treatment of the substrate. Then those seeds were removed at selected areas under action of a finely focussed beam of Ar+ laser (488 nm wavelength) scanned over surface under computer control. At the final step the DF was deposited in DC arc discharge plasma in methane (5%)/hydrogen (95%) gas mixtures [1]. Only at unexposed areas the DF did grow, while the growth was totally suppressed at the laser-modified surface. Micron-sized DF patterns have been fabricated by this way. The mechanisms of nucleation centres annihilation, and the role of ambient atmosphere (air, argon) in this effect are discussed. It is shown also that a laser pre-treatment of Si may result in a significant reducing in DF surface roughness, Ra. Smooth DF with Ra [MATH] were grown, that could be used for optical coating, antifriction coatings and insulating layers in electronic devices

Laser transfer of diamond nanopowder induced by metal film blistering

International audienc

Enhancement of intrinsic protein luminescence in nanosized complex

[No abstract available

Peculiarities of Field Electron Emission from CVD Diamond Films

Results are reported on characterization of the field electron emission from diamond films grown by dc arc discharge plasma CVD onto Si substrates from CH4-H2 gas mixtures. The field electron emission was observed at 15-20 V/µm. Emission current-voltage dependences were studied for films prepared at different CVD conditions and post-growth surface treatment/ modification (ultrathin metal and metal oxide coatings, MW-plasma processing, laser-induced surface graphitization). Features of emission current versus applied field behaviour (including a hysteresis phenomenon, vacuum arc initiation) and ultralow (0.1-0.5 eV) values of effective work function derived from Fowler-Nordheim plot fitting are discussed. A high vacuum scanning tunneling-field emission microscope was applied for simultaneous mapping of field electron emission inten-sity, topography and work function to study electronic and structural properties of field emission centers