Towards near-infrared photoactivation of anticancer metal complexes.

171 p.

Monitorización avanzada en el posoperatorio de las cardiopatías congénitas : motorización hemodinámica avanzada en el posoperatorio de cardiopatías congénitas mediante termodilución transpulmonar y espectroscopia cercana al infrarrojo

196 p. : graf.

Cerebral hemodynamics during graded Valsalva maneuvers

The Valsalva maneuver (VM) produces large and abrupt changes in mean arterial pressure (MAP) that challenge cerebral blood flow and oxygenation. We examined the effect of VM intensity on middle cerebral artery blood velocity (MCAv) and cortical oxygenation responses during (phases I-III) and following (phase IV) a VM. Healthy participants (n = 20 mean +/- SD: 27 +/- 7 years) completed 30 and 90% of their maximal VM mouth pressure for 10 s (order randomized) whilst standing. Beat-to-beat MCAv, cerebral oxygenation (NIRS) and MAP across the different phases of the VM are reported as the difference from standing baseline. There were significant interaction (phase * intensity) effects for MCAv, total oxygenation index (TOI) and MAP (all P < 0.01). MCAv decreased during phases II and III (P < 0.01), with the greatest decrease during phase III (-5 +/- 8 and -19 +/- 15 cm.s(-1) for 30 and 90% VM, respectively). This pattern was also evident in TOI (phase III: -1 +/- 1 and -5 +/- 4%, both P < 0.05). Phase IV increased MCAv (22 +/- 15 and 34 +/- 23 cm.s(-1)), MAP (15 +/- 14 and 24 +/- 17 mm Hg) and TOI (5 +/- 6 and 7 +/- 5%) relative to baseline (all P < 0.05). Cerebral autoregulation, indexed, as the % MCAv/%MAP ratio, showed a phase effect only (P < 0.001), with the least regulation during phase IV (2.4 +/- 3.0 and 3.2 +/- 2.9). These data illustrate that an intense VM profoundly affects cerebral hemodynamics, with a reactive hyperemia occurring during phase IV following modest ischemia during phases II and III.

Pazienteen bihotz eta arnasketa maiztasunen monitorizazioa burmuineko infragorri hurbileko espektroskopia seinaleak erabiliz

Lan honen helburua, burmuineko oxigeno maila neurtzeko NIRS (Near Infrarred Spectroscopy) teknika ez-inbaditzaileaz baliatzen den sistema baten eraginkortasuna neurtzea da, pazientearen parametro fisiologikoak diren bihotz eta arnasketa maiztasunak neurtzerako orduan. Orain arte, pazientearen oxigenazioaren monitorizazioa gauzatzea beharrezkoa den egoeratan, atzamarreko oxigenazio maila neurtzea ahalbidetzen duen PPG (Photoplethysmogram) teknika erabili da. Emergentzia egoeratan, ordea, sistema kardiobaskularrak bizi irauteko nahitaezkoak diren organoei ematen die lehentasuna, garuna eta bihotzari, alegia. Bi organo hauek oxigeno jario jarraituaz hornituak direla egiaztatzeko, ezinbestekoa izango da burmuineko oxigenazio maila neurtzea eta berriki frogatu da NIRS teknikak esparru honetan etorkizun handiko emaitzak eskaini ditzakeela. Hau dela eta, azken urteotan, NIRS teknikak lekua hartu dio orain arte agertoki mediku gehienetan erabilitako PPG teknikari, gaur egun teknika hau aplikazio ugaritan erabiltzen hasia delarik, adibidez kirurgia kardiobaskularraren monitorizazioa edo anestesia orokorraren bitarteko monitorizazioa. NIRS teknikak, garuneko oxigenazio mailaz aparte, pazientearen beste hainbat parametro fisiologikoren neurketa ahalbidetuko balu (arnasketa eta bihotz maiztasuna), agertoki mediku asko erraztuko lituzke, gailu bakar batekin pazientearen bizi-konstante anitzen monitorizazio eramango baitzen aurrera. Tresna hau egingarria dela egiaztatzeko, lehenik eta behin, NIRS seinalea bizi-konstante hauen berri emateko gai dela balioetsi behar da eta hauxe da, hain zuzen, proiektu honen xede nagusia. Azken helburu hau lortzeko, hainbat azpi-helburu proposatzen dira hemen aurkeztuko den proiektuan: lehenik eta behin, NIRS seinaleak eta bizi konstante hauek era fidagarrian lortzea ahalbidetzen duten seinaleak biltegiratzen dituen datu base bat sortuko da. Datu base hau osatzeko, aurreko seinale guztiak aldi berean eskuratuko dituen neurketa sistema sinkrono bat sortzea ezinbestekoa izango da eta azkenik, NIRS seinaleen eraginkortasuna ebaluatzeko, seinaleen prozesaketan oinarritutako hainbat algoritmo garatuko dira.

Human LDL Structural Diversity Studied by IR Spectroscopy

Lipoproteins are responsible for cholesterol traffic in humans. Low density lipoprotein (LDL) delivers cholesterol from liver to peripheral tissues. A misleading delivery can lead to the formation of atherosclerotic plaques. LDL has a single protein, apoB-100, that binds to a specific receptor. It is known that the failure associated with a deficient protein-receptor binding leads to plaque formation. ApoB-100 is a large single lipid-associated polypeptide difficulting the study of its structure. IR spectroscopy is a technique suitable to follow the different conformational changes produced in apoB-100 because it is not affected by the size of the protein or the turbidity of the sample. We have analyzed LDL spectra of different individuals and shown that, even if there are not big structural changes, a different pattern in the intensity of the band located around 1617 cm 21 related with strands embedded in the lipid monolayer, can be associated with a different conformational rearrangement that could affect to a protein interacting region with the receptor.