Spectroscopic Insights of an Emissive Complex between 4'-N,N-Diethylaminoflavonol in Octa-Acid Deep-Cavity Cavitand and Rhodamine 6G.

Excited-state chemistry relies on the communication between molecules, making it a crucial aspect of the field. One important question that arises is whether intermolecular communication and its rate can be modified when a molecule is confined. To explore the interaction in such systems, we investigated the ground and excited states of 4'-N,N-diethylaminoflavonol (DEA3HF) in an octa acid-based (OA) confined medium and in ethanolic solution, both in the presence of Rhodamine 6G (R6G). Despite the observed spectral overlap between the flavonol emission and the R6G absorption, as well as the fluorescence quenching of the flavonol in the presence of R6G, the almost constant fluorescence lifetime at different amounts of R6G discards the presence of FRET in the studied systems. Steady-state and time-resolved fluorescence indicate the formation of an emissive complex between the proton transfer dye encapsulated within water-soluble supramolecular host octa acid (DEA3HF@(OA)2) and R6G. A similar result was observed between DEA3HF:R6G in ethanolic solution. The respective Stern-Volmer plots corroborate with these observations, suggesting a static quenching mechanism for both systems.

Interaction Study between ESIPT Fluorescent Lipophile-Based Benzazoles and BSA.

In this study, the interactions of ESIPT fluorescent lipophile-based benzazoles with bovine serum albumin (BSA) were studied and their binding affinity was evaluated. In phosphate-buffered saline (PBS) solution these compounds produce absorption maxima in the UV region and a main fluorescence emission with a large Stokes shift in the blue-green regions due to a proton transfer process in the excited state. The interactions of the benzazoles with BSA were studied using UV-Vis absorption and steady-state fluorescence spectroscopy. The observed spectral quenching of BSA indicates that these compounds could bind to BSA through a strong binding affinity afforded by a static quenching mechanism (Kq~1012 L·mol-1·s-1). The docking simulations indicate that compounds 13 and 16 bind closely to Trp134 in domain I, adopting similar binding poses and interactions. On the other hand, compounds 12, 14, 15, and 17 were bound between domains I and III and did not directly interact with Trp134.

Short- and long-term survival has improved after radical cystectomy for bladder cancer in Québec during the years 2000-2015.

BACKGROUND AND OBJECTIVES: We evaluated the short- and long-term outcome in bladder cancer (BC) patients treated with radical cystectomy (RC) in Québec (Canada). METHODS: Data were collected from provincial registries on all BC patients who underwent RC in Québec province in 2000-2015. Outcomes were hospitalization rates and survival. Survival analyses were conducted using log-rank tests and Cox proportional hazards models. RESULTS: In total, 4450 patients were included in our analysis. RC was increasingly conducted by higher-volume surgeons in larger, higher-volume, academic hospitals. Comparing patients treated in 2010-2015 to 2000-2009, recently treated patients had shorter postoperative hospital stays (absolute difference, 0.9 days, P < 0.001) but also a higher readmission rate (25.0% vs 21.1% in the 30 days following discharge, P = 0.003). Overall (5-year rates 50.9% vs 42.7%, P < 0.001) and BC-specific survival (61.3% vs 55.5%, P < 0.001) had significantly improved. In multivariable analyses, overall survival was significantly better in recently treated patients (hazard ratio [HR], 0.66; 95% confidence interval [CI], 0.60-0.73), younger patients (HR, 1.16; 95% CI, 1.14-1.19), patients residing closer to the hospital (HR, 1.03; 95% CI, 1.01-1.06), and patients treated by high-volume surgeons (HR, 0.88; 95% CI, 0.82-0.94). CONCLUSIONS: Survival in BC patients after RC has improved in recent years. Other predictors for survival are younger age, shorter distance between patients' residences and hospitals, and higher surgeon's RC loads.

Proton transfer in fluorescent secondary amines: synthesis, photophysics, theoretical calculation and preparation of photoactive phosphatidylcholine-based liposomes.

In this article, new fluorescent lipophilic based benzazoles were synthesized from the reaction between photoactive formyl derivatives and aliphatic amines followed by NaBH4 reduction with good yields. The photophysics of the benzazoles was investigated experimentally and theoretically. These compounds present absorption maxima in the UV region (∼339 nm) and fluorescence emission maxima in the cyan to green region with a large Stokes shift (∼175 nm) due to a proton transfer process in the excited state. Two fluorophores were successfully used as a proof of concept to produce stable photoactive liposomes prepared from phosphatidylcholine (PC) and were characterized by zeta potential, small angle X-ray scattering (SAXS), FTIR and UV-Vis experiments (turbidity). The scattering data indicate that the presence of compounds 20 and 23 reduces the overall surface charge of the PC vesicles, possibly due to the partial neutralization of phosphatidic acid and/or phosphatidylinositol phosphate by the amine groups, and they also modify the structural features of the assemblies, leading, in particular, to a reduction in the thickness of the hydrophobic inner segment (tt) of the liposomes. DFT and TD-DFT calculations were performed with the ωB97XD functional. Geometric analyses show that the 2-(2'-hydroxyphenyl)benzazolic planar portion allows an effective ππ* electronic transition. Additionally, the calculations indicate a small energy barrier to proton transfer. The results of the absorption and emission maxima show a slight solvent influence on the wavelengths.

Experimental and theoretical investigation of long-wavelength fluorescence emission in push-pull benzazoles: intramolecular proton transfer or charge transfer in the excited state?

This study presents the synthesis, characterisation and theoretical calculations of compounds that contain electron donor and withdrawing groups connected through a π-conjugated benzazolic structure. The compounds in solution show an absorption maximum in the UV-visible spectrum (380-390 nm) due to spin and symmetry allowed electronic 1ππ* transitions with no clear evidence for charge transfer in either compound in the ground state. A fluorescence emission located in the violet-blue-green region, tailored by solvent polarity, with a large Stokes shift was observed. Taking the long-wavelength emission into account, the Lippert-Mataga plot indicates a positive solvatochromism in the solvent polarity function (Δf) range 0.02-0.20, related to the occurrence of an ICT mechanism in the excited state. At Δf greater than 0.20, the polarity of the medium seems no longer to increase the stabilization of the compounds, reaching a plateau. Time-dependent density functional theory (TD-DFT) and resolution-of-identity second-order approximate coupled-cluster (RI-CC2) calculations were also used to better understand the excited state of these compounds. The results indicated that ESIPT was disfavoured in the compounds, mainly in polar solvents, and the emission wavelengths were primarily associated with ICT. In summary, in these push-pull compounds, the electron donating and withdrawing groups do not favour the ESIPT process.

Proton-Transfer-Based Azides with Fluorescence Off-On Response for Detection of Hydrogen Sulfide: An Experimental, Theoretical, and Bioimaging Study.

This work describes the synthesis of photoactive proton transfer compounds based on the benzazolic core containing the azide group. The compounds present absorption in the UV region and fluorescence emission in the visible region of the spectra with large Stokes shift due to a phototautomerism in the excited state (ESIPT). The azide location on the benzazolic structure presented a noteworthy role on their photophysics, leading to fluorescence quenching. A photophysical study was performed in the presence of NaHS to evaluate their application as an H2S sensor. The methodology employed was the reduction of azides to amines using NaHS to mimic H2S, resulting in an off-on response fluorescence mechanism. The observed photophysical features were successfully used to explore the azides as fluorescent probes in biological media. In addition, DFT and TD-DFT calculations with the CAM-B3LYP/cc-pVDZ and CAM-B3LYP/jun-cc-pVTZ level, respectively, were performed in order to understand the photophysics features of azide derivatives, where the main interest was to investigate the fluorescence quenching experimentally observed in the azide derivatives.

Photoacidity as a tool to rationalize excited state intramolecular proton transfer reactivity in flavonols.

This work presents the determination of acidic strengths at the electronic ground and excited states (pKa and ) of three flavonol derivatives using electronic absorption and fluorescence emission spectroscopy. The differences of the pKa and values were successfully correlated with the molecular structures according to the substitution pattern at the flavonol structure (hydrogen, diethylamino or fluoro moieties). In order to obtain more information about the observed photoacidity of these superacids, geometry optimizations and excitation energy calculations were performed at the CAM-B3LYP/6-311++G(d,p) level for their neutral, protonated and deprotonated species.

Correction: Photoinduced electron transfer across an organic molecular wall: octa acid encapsulated ESIPT dyes as electron donors.

Correction for 'Photoinduced electron transfer across an organic molecular wall: octa acid encapsulated ESIPT dyes as electron donors' by Fabiano S. Santos et al., Photochem. Photobiol. Sci., 2017, 16, 840-844.

Photoinduced electron transfer across an organic molecular wall: octa acid encapsulated ESIPT dyes as electron donors.

Efficient photoinduced electron transfer from proton transfer dyes encapsulated within water soluble supramolecular host octa acid to electron acceptors present outside the capsule was observed in aqueous solution. 4,4'-Dimethylviologen dichloride was found to be the best acceptor compared to N-methylpyridinium iodide, most likely due to its better binding with the exterior of the host octa acid walls [corrected].

Predictors of costs associated with radical cystectomy for bladder cancer: A population-based retrospective cohort study in the province of Quebec, Canada.

BACKGROUND AND OBJECTIVES: There is paucity of studies on the predictors of bladder cancer (BC) management costs. We aimed to determine predictors of costs associated with radical cystectomy (RC) for BC. METHODS: We conducted a retrospective analysis in a cohort of 2,759 patients who underwent RC for BC between 2000 and 2009. We analyzed predictors of pre-surgery, RC, post-surgery, and total costs. The following variables were considered as potential predictors: age, gender, hospital/surgeon case load, academic hospital, and geo-administrative region. Multivariate linear regression was used to determine predictors. RESULTS: Predictors of pre-surgery costs were: age (ß = 808.64, P < 0.0001) and having surgery in an academic hospital (ß = 511.42, P = 0.003). Increased RC costs were associated with age (ß = 196.73, P = 0.0006), hospital/surgeon annual load (ß = 484.45 and ß = 254.21, P < 0.0001, respectively). Having surgery in academic hospitals and geographic region were significant predictors of low RC costs (ß = -1085.82 and ß = -449.31, P < 0.0001, respectively). Increasing age and the presence of post-operative complications were predictors of high post-operative costs (ß = 623.48, ß = 5781.44, P = 0.01, respectively), while hospital load was associated with low post-surgery costs (ß = -949.79, P < 0.0001). CONCLUSION: Patients' age and surgery performed by high-volume health providers were predictive factors of high RC costs. Low RC costs were associated with surgeries performed in academic hospitals.

Survival after Radical Cystectomy for Bladder Cancer in Relation to Prior Non-Muscle Invasive Disease in Quebec.

INTRODUCTION AND OBJECTIVES: The aim of this study was to assess if there is a difference in survival after radical cystectomy (RC) when examined in relation to prior non-muscle invasive bladder cancer (NMIBC) disease vs. invasive cancer de novo at time of diagnosis. METHODS: We conducted a retrospective study of all patients who underwent RC within Quebec health insurance medical services database during the years (2000-2009). Overall survival (OS) outcome was assessed with Kaplan-Meier curves and hazard ratios (HRs) adjusted for age and gender. RESULTS: A total of 2,671 subjects met the eligibility criteria. Among them, 19.8% had presumed prior NMIBC that further progressed to invasive disease. Median survival after RC for patients with presumed prior NMIBC was 4.3 years as compared to patients with presumed invasive disease de novo 3.7 years (p = 0.007, Wilcoxon test). Patients with presumed NMIBC at the time of diagnosis had a 16% decrease in the risk of mortality after RC, when compared to patients with presumed invasive BC de novo (HR 0.84, 95% CI 0.73-0.96 (p = 0.0166)). CONCLUSION: Our results suggest a slightly better prognosis, regarding OS after RC for patients with presumed NMIBC who progressed to invasive disease, when compared to patients with presumed invasive disease de novo at the time of diagnosis.

Antimalarial drugs for preventing malaria during pregnancy and the risk of low birth weight: a systematic review and meta-analysis of randomized and quasi-randomized trials.

BACKGROUND: It is known that antimalarial drugs reduce the risk of low birth weight (LBW) in pregnant patients. However, a previous Cochrane review did not evaluate whether the level of antimalarial drug resistance could modify the protective effect of antimalarial drugs in this regard. In addition, no systematic review exists comparing current recommendations for malaria prevention during pregnancy to alternative regimens in Africa. Therefore, we conducted a comprehensive systematic review and meta-analysis to assess the efficacy of antimalarial drugs for malaria prevention during pregnancy in reducing the risk of LBW. METHODS: We searched PubMed, Embase and the Cochrane Central Register of Controlled Trials (CENTRAL) for articles published up to 21 November 2014, in English or French, and identified additional studies from reference lists. We included randomized and quasi-randomized studies reporting LBW as one of the outcomes. We extracted data and assessed the risk of bias in selected studies. All pooled analyses were based on a random effect model, and we used a funnel plot and trim and fill method to test and adjust for publication bias. RESULTS: A total of 25 studies met the inclusion criteria (37,981 subjects). Compared to no use, all combined antimalarial drugs were associated with a 27% (RR 0.73, 95% CI 0.56-0.97, ten studies) reduction in the risk of LBW. The level of antimalarial drug resistance modified the protective effect of the antimalarial drug used for prevention of LBW during pregnancy. Sulfadoxine-pyrimethamine was not associated with a reduction in the risk of LBW in regions where the prevalence of the dihydropteroate synthase 540E mutation exceeds 50% (RR 0.99, 95% CI 0.80-1.22, three studies). The risk of LBW was similar when sulfadoxine-pyrimethamine was compared to mefloquine (RR 1.05, 95% CI 0.86-1.29, two studies). CONCLUSION: Prophylactic antimalarial drugs and specifically sulfadoxine-pyrimethamine may no longer protect against the risk of LBW in areas of high-level resistance. In Africa, there are currently no suitable alternative drugs to replace sulfadoxine-pyrimethamine for malaria prevention during pregnancy.

Predictors of preoperative delays before radical cystectomy for bladder cancer in Quebec, Canada: a population-based study.

OBJECTIVES: To characterise and measure different components of preoperative delays experienced by patients with bladder cancer before radical cystectomy (RC) in the province of Quebec, Canada and to identify the predictors of long waiting times. METHODS: We conducted a retrospective cohort study using the data of patients who underwent RC for bladder cancer between 2000 and 2009 in Quebec. The cohort was obtained with the linkage of two provincial health databases: the Régie de l'assurance maladie du Québec database (data on medical services dispensed to Quebec residents), and the Fichier des évenements démographiques de l'Institut de la statistique du Québec database (demographic data on births and deaths). For the entire cohort, we determined several components of delay from first medical visit related to bladder cancer symptoms until RC. Predictors of long delays were analysed using logistic regression. RESULTS: We analysed a total of 2778 patients who met the inclusion criteria. The median urologist referral delay was 32 days. The median delays between first urologist visit and RC and between transurethral resection of bladder tumour (TURBT) to RC were 90 days and 46 days, respectively. The median overall delay was 116 days. All components of delay progressively increased from the decade of the 1990s to the decade of the 2000s. Male gender was a protective factor for several components of delay, which suggests that gender-related variations may exist in the course of care for bladder cancer (odds ratio 0.67, 95% CI 0.50-0.89 for overall delay). Patient age and gender were associated with delayed urologist referral, delayed time to TURBT, and long overall waiting time. Factors related to the health system were associated with long cystoscopy delays. CONCLUSION: Median preoperative delays among patients with bladder cancer have been increasing and remain unacceptably long. Patient's age, gender and type of hospital facility were associated with long waiting times.

High hospital and surgeon volume and its impact on overall survival after radical cystectomy among patients with bladder cancer in Quebec.

INTRODUCTION AND OBJECTIVES: Previous studies reported improved outcomes for bladder cancer patients who had radical cystectomy (RC) performed by surgeons and hospitals with high annual RC volumes. The objective of this study was to determine the effect of high hospital and surgeon volume on overall survival after RC for bladder cancer in Quebec. METHODS: We conducted a retrospective cohort study using data of patients who underwent RC for bladder cancer from 2000 to 2009. The cohort was obtained with the linkage of two health databases: the RAMQ database (data on medical services) and the ISQ database (vital status data). Hospital and surgeon volumes were defined as the average annual number of RC performed at an institution or by surgeon, respectively, during the study period. We considered high hospital and surgeon volume those found in the third and fourth quartiles of the distribution of hospital and surgeon volumes. The effect of high hospital and surgeon volume on survival was assessed by multivariate Cox proportional hazards models. RESULTS: We analyzed a total of 2,778 patients who met inclusion criteria (75 % males). High hospital volume and surgeons were found to be significantly associated with improved overall survival (HR = 0.87, 95 % CI: 0.78-0.97 and HR = 0.81, 95 % CI: 0.71-0.91, respectively). The combined effect of high-volume hospital and high-volume surgeon decreased by 20 % the risk of long-term mortality (HR = 0.80, 95 % CI: 0.70-0.91). CONCLUSIONS: Compared to low-volume providers, having RC for bladder cancer performed in high-volume hospitals or by high-volume surgeon was associated with improved overall survival.

Radical cystectomy in patients over 80 years old in Quebec: A population-based study of outcomes.

OBJECTIVES: To document radical cystectomy (RC) outcomes in patients over 80 years old across Quebec during the years 2000-2009 and to examine potentially related factors. METHODS: Within Quebec health insurance medical services database, we identified patients over 80 years who underwent RC. The outcomes analyzed were post-operative complications, mortality rates at 30, 60 and 90 days and overall survival. RESULTS: A total of 275 patients over 80 years old had RC performed in 38 hospitals across Quebec. Among them, 33% had major post-operative complications with 16% having more than one complication. Mortality rates at 30, 60 and 90 days were 5.8%, 9.8% and 13% respectively. 44.3% of RCs were performed in seven academic hospitals with mortality rates of 2.5%, 6.5% and 9% respectively. Community hospitals had mortality of 8.5%, 12.4% and 16.3% respectively (P < 0.001). The cohort 5-year overall survival rate was 27%. The presence of post-operative complications and the number of complications negatively affected overall survival (P < 0.001) CONCLUSION: Patients over 80 years of age have high post-RC mortality rates, especially at 90 days. In addition, it appears that they have lower post-operative mortality if their RCs were performed in academic centers. Mortality rates and complications can be used when obtaining informed consent.

Health-care services utilization and costs associated with radical cystectomy for bladder cancer: a descriptive population-based study in the province of Quebec, Canada.

BACKGROUND: Bladder cancer (BC) has the highest lifetime treatment costs per patient of all cancers. The objective of this study was to characterize the use of health-care services and costs associated with BC among patients who underwent radical cystectomy (RC) in the province of Quebec. METHODS: We conducted a descriptive study in a retrospective cohort of patients who underwent RC for BC between 2000 and 2009. Data was obtained from two health administrative databases (RAMQ and ISQ). We calculated average costs per patient and total costs in 2014 Canadian dollars for the following components of costs: 1) Pre-surgery costs (pre and post-urologist consultations, urologist consultations, cystoscopies, TURBTs, imaging procedures); 2) Costs of radical cystectomy and 3) Post-surgery costs (urologist consultations, post-operative consultations, medical oncologist consultations, imaging procedures and post-operative complication management). ARIMA models were used to evaluate trends in average costs per patient over the study period. RESULTS: Among 2759 patients included in the study (75% men), average pre-surgery costs, RC costs, and post-surgery costs were estimated at 3762$, 18979$ and 4770$, respectively. RC cost was responsible for 69% of total costs, followed by post-operative consultations (7.8%), post-operative complications and TURBTs (6% of total costs, each). Academic hospitals performed RC at a lower average cost, compared to community hospitals (difference of $1000, p < .0001). A decreased trend in post-surgery costs was detected in the year 2009. CONCLUSIONS: Costs of RC, TURBT, consultations and post-operative complications were the most important economic components of total RC cost per patient in Quebec. Academic hospitals performed RC at a lower cost, compared to community hospitals.

Excited state chemistry of flavone derivatives in a confined medium: ESIPT emission in aqueous media.

The excited state behavior of two flavone derivatives 3-hydroxyflavone and 4'-N,N-diethylaminoflavonol in a confined medium indicates that supramolecular effects could alter the nature of the fluorescence emission. Within the octa acid host the neutral unionized species of these two dyes are present showing large Stokes shifted emission due to intramolecular proton transfer, a pattern different from that in aqueous medium.

[Physical therapy in pediatric primary care: a review of experiences]. / Assistência fisioterapêutica na atenção primária à saúde infantil: uma revisão das experiências.

OBJECTIVE: To review pediatric physical therapy experiences described in the literature and to analyze the production of knowledge on physical therapy in the context of pediatric primary health care (PPHC). METHODS: A systematic review was conducted according to the PRISMA criteria. The following databases were searched: MEDLINE, LILACS, SciELO, PubMed, Scopus and Cochrane; Brazilian Ministry of Health's CAPES doctoral dissertations database; and System for Information on Grey Literature in Europe (SIGLE). The following search terms were used: ["primary health care" and ("physical therapy" or "physiotherapy") and ("child" or "infant")] and equivalent terms in Portuguese and Spanish, with no restriction on publication year. RESULTS: Thirteen articles from six countries were analyzed and grouped into three main themes: professional dilemmas (three articles), specific competencies and skills required in a PPHC setting (seven articles), and practice reports (four articles). Professional dilemmas involved expanding the role of physical therapists to encompass community environments and sharing the decision-making process with the family, as well as collaborative work with other health services to identify the needs of children. The competencies and skills mentioned in the literature related to the identification of clinical and sociocultural symptoms that go beyond musculoskeletal conditions, the establishment of early physical therapy diagnoses, prevention of overmedication, and the ability to work as team players. Practice reports addressed stimulation in children with neurological diseases, respiratory treatment, and establishing groups with mothers of children with these conditions. CONCLUSIONS: The small number of studies identified in this review suggests that there is little knowledge regarding the roles of physical therapists in PPHC and possibly regarding the professional abilities required in this setting. Therefore, further studies are required to provide data on the field, along with a continuing education effort on the part of physical therapists.

Malignant hyperthermia in maxillofacial surgery: Literature review supported by case presentation.

OBJECTIVE: Malignant hyperthermia (MH) is characterized by a state of hypermetabolism after exposure to halogenated inhalational anesthetics or succinylcholine. The aims of this study were to carry out an updated review on the subject and report an illustrative case of MH in urgent maxillofacial surgery. MATERIAL AND METHODS: A search of the PubMed/MEDLINE database using the keyword "malignant hyperthermia" was performed including articles published over the last 11 years in English, Spanish or Portuguese. Exclusion criteria were similar presentations but not associated with MH and cases not related to the use of anesthetic drugs as a trigger of the condition. CASE REPORT: A 45-year-old man (75 kg, ASA status IE) with a negative family history for neuromuscular diseases, victim of a car accident with a facial fracture, underwent surgery under balanced general anesthesia and developed signs of MH 4 h after anesthesia induction. In our patient, the causative agent was sevoflurane and the diagnosis of MH was confirmed, subsequently, by muscle biopsy. RESULTS/DISCUSSION: Overall, 44 cases of MH were found. According to the recent literature, MH shows a male predilection (3:1) and the mean age of patients is 32.2 ± 22.2 years. The most frequently cited causative agents were sevoflurane (30.5%), isoflurane (22.2%), and sevoflurane + succinylcholine (13.8%). The most common clinical indicators included hypercarbia (88.8%), hyperthermia (86.1%), and tachycardia (63.8%). Dantrolene was administered in 24 cases. The outcome was favorable in 31 cases (86.1%). The in vitro muscle contracture test (IVCT) was performed in only 15 patients and all of them tested positive. In our patient, the causative agent was sevoflurane and the diagnosis of MH was confirmed by muscle biopsy. CONCLUSION: The mortality from MH is still high and an early clinical diagnosis and specific treatment with dantrolene are necessary for a favorable outcome. A complete understanding will allow better management of patients with MH. At present, the best management is to identify susceptible patients and to avoid triggering agents, combined with vigilant monitoring.

Evidence for excited state intramolecular charge transfer in benzazole-based pseudo-stilbenes.

Two azo compounds were obtained through the diazotization reaction of aminobenzazole derivatives and N,N-dimethylaniline using clay montmorillonite KSF as catalyst. The synthesized dyes were characterized using elemental analysis, Fourier transform infrared spectroscopy, and (13)C and (1)H NMR spectroscopy in solution. Their photophysical behavior was studied using UV-vis and steady-state fluorescence in solution. These dyes present intense absorption in the blue region. The spectral features of the azo compounds can be related to the pseudo-stilbene type as well as the E isomer of the dyes. Excitation at the absorption maxima does not produce emissive species in the excited state. However, excitation around 350 nm allowed dual emission of fluorescence, from both a locally excited (LE, short wavelength) and an intramolecular charge transfer (ICT, long wavelength) state, which was corroborated by a linear relation of the fluorescence maximum (ν(max)) versus the solvent polarity function (Δf) from the Lippert-Mataga correlation. Evidence of TICT in these dyes was discussed from the viscosity dependence of the fluorescence intensity in the ICT emission band. Theoretical calculations were also performed in order to study the geometry and charge distribution of the dyes in their ground and excited electronic states. Using DFT methods at the theoretical levels BLYP/Aug-cc-pVDZ, for geometry optimizations and frequency calculations, and B3LYP/6-311+G(2d), for single-point energy evaluations, the calculations revealed that the least energetic and most intense photon absorption leads to a very polar excited state that relaxes non-radioactively, which can be associated with photochemical isomerization.