Reaction of amines with 8-methylthioBODIPY: dramatic optical and laser response to amine substitution.

A thorough study of the photophysical and laser properties of 8-aminoboron dipyrromethene dyes was undertaken to determine the role of amine substitution and spatial disposition on the properties of the dyes. It was found that the fluorescent and laser response varied significantly. Although primary amines give rise to highly fluorescent products at the blue edge of the visible region, secondary amines yield nonfluorescent analogues in polar media. The crystal structures of two analogues are reported and described. Steric hindrance and the higher electron-releasing ability of the amine favor the formation of a quenching intramolecular charge-transfer state. Accordingly, boron dipyrromethene derivatives with primary amines exhibited laser emission with efficiencies of up to 44%. Besides, the more efficient derivative was also the most photostable, leading to a significant improvement in the lasing performance with regard to previously reported 8-aminoboron dipyrromethene derivatives. An increase in the solvent polarity, and mainly the presence of tertiary cyclic amines, led to a dramatic decrease or even the loss of the laser action.

Synthesis, solvatochromism, aggregation-induced emission and cell imaging of tetraphenylethene-containing BODIPY derivatives with large Stokes shifts.

A series of tetraphenylethene-containing BODIPYs with emissions from visible to near-IR and large Stokes shifts up to 142 nm have been designed and synthesized. They show solvatochromic fluorescence and can be utilized as fluorescent visualizers for intracellular imaging.

8-AminoBODIPYs: cyanines or hemicyanines? The effect of the coplanarity of the amino group on their optical properties.

The role of the amino group twisting ability in the BODIPY photophysics for nonsterically hindered and constrained molecular structures was studied. When a coplanar disposition of the amino and the BODIPY core is feasible, a hemicyanine-like delocalized π-system gives rise to novel blue and efficient BODIPY laser dyes. The key role of such rotamer is confirmed by newly synthesized derivatives where the amino and the BODIPY core are electronically decoupled by steric repulsions.

New 8-amino-BODIPY derivatives: surpassing laser dyes at blue-edge wavelengths.

The development of highly efficient and stable blue-emitting dyes to overcome some of the most important shortcomings of available chromophores is of great technological importance for modern optical, analytical, electronic, and biological applications. Here, we report the design, synthesis and characterization of new tailor-made BODIPY dyes with efficient absorption and emission in the blue spectral region. The major challenge is the effective management of the electron-donor strength of the substitution pattern, in order to modulate the emission of these novel dyes over a wide spectral range (430-500 nm). A direct relationship between the electron-donor character of the substituent and the extension of the spectral hypsochromic shift is seen through the energy increase of the LUMO state. However, when the electron-donor character of the substituent is high enough, an intramolecular charge-transfer process appears to decrease the fluorescence ability of these dyes, especially in polar media. Some of the reported novel BODIPY dyes provide very high fluorescence quantum yields, close to unity, and large Stokes shifts, leading to highly efficient tunable dye lasers in the blue part of the spectrum; this so far remains an unexploited region with BODIPYs. In fact, under demanding transversal pumping conditions, the new dyes lase with unexpectedly high lasing efficiencies of up to 63 %, and also show high photostabilities, outperforming the laser action of other dyes considered as benchmarks in the same spectral region. Considering the easy synthetic protocol and the wide variety of possible substituents, we are confident that this strategy could be successfully extended for the development of efficient blue-edge emitting materials and devices, impelling biophotonic and optoelectronic applications.

8-PropargylaminoBODIPY: unprecedented blue-emitting pyrromethene dye. Synthesis, photophysics and laser properties.

Highly emitting 8-propargylaminoBODIPY (8-PAB) 2 was prepared in 94% yield. Unlike any other BODIPY structure hitherto described in the literature, 2 displays efficient emission in the blue region of the visible spectrum with a fluorescence quantum yield up to 0.94 and high laser efficiency (35%) at 483 nm.

[Endocarditis with Ionescu-Shiley's bioprosthesis. Long-term results]. / Endocarditis con la bioprótesis de Ionescu-Shiley. Resultados a largo plazo.

With the aim to attesting the ability of treated pericardial tissue to resist infection we analyzed the incidence of prosthetic valve endocarditis in 541 operative survivors with the Ionescu-Shiley (I-S) valve since January 1977. A total of 580 valves were available for the study, 21 (3.8%) sustained I-S endocarditis or 0.65% patients/annum. The mean age was 53.2 years; male/female ratio was 16/5. Native endocarditis was present in 20 cases (3.6%). There were 13 aortic endocarditis (2 in cases of multiple replacement) and eight mitral. The interval between insertion and endocarditis ranged from 2 weeks to 108 months (means 31); 8 cases were early I-S endocarditis (38%) and 13 late endocarditis (62%). The organisms isolated were: Staphylococcus (epidermidis, aureus) in 10 cases. Streptococcus (viridans, fecalis) in 7 cases, gram negative in three and no organism was cultured in 3 cases. The outcome was as follows: specific medical treatment in 4 cases (one early), valve re-replacement in 11 (four early) from whom eight survived, and 6 patients died with unspecific medical treatment. The total mortality rate 9/21 (43%), in early endocarditis 5/8 (62.5%) and in late endocarditis 5/13 (38%). Operative and necropsy findings in 12/21 showed always periprosthetic abscess but no leaflet perforations. The rate of I-S valve endocarditis compares favourably with other valve substitutes. Early re-replacement combined with adequate antibiotic treatment is mandatory according to our experience.

Simplified aortic cannulation.

Cannulation of the ascending aorta for cardiopulmonary bypass can be complicated by excessive bleeding or improper (too low) placement. A simple method of cannulation that avoids these problems is presented. This technique has been utilized in more than 1,000 patients without untoward complications.

Intraoperative assessment of tricuspid valve function after conservative repair.

It is desirable to repair coexistent tricuspid valve pathology at the time of mitral valve corrections. Conservative tricuspid repair may consist of commissurotomy, annuloplasty, or both. It is important that the repair be appropriate or tricuspid valve replacement may be necessary. A simple reproducible method of intraoperative testing for tricuspid valve insufficiency has been developed and used in 25 patients. Fifteen patients have been recatheterized, and the correlation between the intraoperative and postoperative findings has been consistent.