In the continuation of previous studies on carbon‐rich meso‐tetraarylporphyrins featuring 2,7‐fluorene units at their periphery, the effect of changing the peripheral dendritic arms for linear arms ...on their oxygen‐photosensitizing ability, their fluorescence and their two‐photon absorption (2PA) properties is now analyzed. Thus, starburst porphyrins possessing up to twenty conjugated fluorenyl units were isolated and studied. More precisely, a series of five new free‐base porphyrins featuring fully conjugated arms incorporating an increasing number of fluorenyl groups connected via 1,2‐alkenyl spacers were synthesized, along with their Zn(II) complexes. Upon excitation in the arm‐centred π‐π* absorption band, an efficient energy transfer takes place from the peripheral fluorenyl units to the central porphyrin core, leading to intense red‐light emission and oxygen photosensitization by the latter. More interestingly, while the linear optical properties of these porphyrins were only slightly improved compared to those of their dendrimer analogues for photodynamic therapy (PDT) or fluorescence imaging, their 2PA cross‐sections were much more significantly boosted, evidencing the key role played by different structures on nonlinear optical properties. Finally, by comparison with other porphyrin‐based two‐photon photosensitizers reported in the literature, we show that these new “semi‐disconnected” starburst systems exhibit a remarkable trade‐off between intrinsic 2PA, fluorescence and oxygen photosensitization.
New Starburst porphyrins possessing up to twenty conjugated fluorenyl units have been synthesized. Their detailed oxygen‐photosensitizing ability, their fluorescence and their two‐photon absorption properties are discussed
Diet quality is related to the risk for depression and anxiety in adults and adolescents; however, the possible impact of maternal and early postnatal nutritional exposures on children's subsequent ...mental health is unexplored.
The large prospective Norwegian Mother and Child Cohort Study recruited pregnant women between 1999 and 2008. Data were collected from mothers during pregnancy and when children were 6 months and 1.5, 3, and 5 years of age. Latent growth curve models were used to model linear development in children's internalizing and externalizing problems from 1.5 to 5 years of age as a function of diet quality during pregnancy and at 1.5 and 3 years. Diet quality was evaluated by dietary pattern extraction and characterized as "healthy" or "unhealthy." The sample comprised 23,020 eligible women and their children. Adjustments were made for variables including sex of the child, maternal depression, maternal and paternal age, maternal educational attainment, household income, maternal smoking before and during pregnancy, mothers' parental locus of control, and marital status.
Higher intakes of unhealthy foods during pregnancy predicted externalizing problems among children, independently of other potential confounding factors and childhood diet. Children with a high level of unhealthy diet postnatally had higher levels of both internalizing and externalizing problems. Moreover, children with a low level of postnatal healthy diet also had higher levels of both internalizing and externalizing problems.
Among this large cohort of mothers and children, early nutritional exposures were independently related to the risk for behavioral and emotional problems in children.
A new family of conjugated meso‐tetraphenylporphyrin‐based dendrimers with four (TPP1, TPP2), eight (TPP3, TPP4, TPP5) and up to sixteen (TPP6) fluorenyl groups has been synthesized and fully ...characterized. These tetraphenylporphyrin‐cored dendrimers present peripheral alkynyl π‐conjugated dendrons with fluorenyl termini. The meso‐aryl rings of these porphyrins are functionalized either in para‐ (TPP1, TPP2, and TPP3) or meta‐positions (TPP4, TPP5, and TPP6). Their detailed luminescence properties are discussed in reference to two porphyrins lacking fluorenyl dendrons (TPP‐H1,2,3 and TPP‐H4,5,6). A strong dependence of their luminescence quantum yield and lifetime on their structures is stated, their nonlinear optical properties were also discussed.
Seeing porphyrins in a new light! A new family of conjugated meso‐tetraphenylporphyrin‐based dendrimers with fluorenyl arms has been synthesized (see figure). Their detailed luminescence properties and their nonlinear optical properties are discussed.
The design of dendrimers featuring conjugated fluorenyl dendrons via new connectors allows evaluating the importance of the role of these junctions and the nature of the core, on the optical ...properties of interest. In the continuation of our sustained interest for dendrimers and their use as luminescent labels for bioimaging, we wondered about the effect of changing the central porphyrin core for a phthalocyanine one in these macromolecular structures. Thus, a related phthalocyanine-based dendrimer possessing up to eight conjugated 9,9-dibutyl-2-fluorenyl endgroups was designed, and for the first time, these endgroups are linked to the central phthalocyanine core by new fluorenyl-based connectors C2 instead of the more classic 1,3,5-phenylene one C1. This original dendrimer was characterized and studied and as for porphyrin analogues, it was found that an efficient energy transfer occurs from the peripheral fluorenyl units to the central phthalocyanine core, leading to an intense red light emission. The luminescence is improved compared to that of their porphyrin-cored analogues for bioimaging, evidencing the key role played by the central core in this respect and the nature of the connector Cn. The impact of the structural changes of the core in relation with the impact resulting from the changes in dendron connectors is discussed.
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Two new meso -tetrafluorenylporphyrin-cored dendrimers 1 and 2 have been synthesized and characterized. The peripheral fluorenyl units of these dendrimers are linked to the central ...tetrafluorenylporphyrin ( TFP ) core by original fluorene-based connectors instead of the more classic 1,3,5-phenylene unit. Selected linear and non-linear optical (LO and NLO) properties were determined for these dendrimers via absorption or emission studies and by two-photon excited fluorescence (TPEF) measurements. Dendrimer 1 , which has a conjugated and quite rigid structure, exhibits a significantly higher two-photon absorption (2PA) cross-section than dendrimer 2 , presenting a non-conjugated and more flexible structure, as well as better luminescence and singlet oxygen activation quantum yields. Both dendrimers exhibit higher 2PA cross-sections than several closely related TFP -based dendrimers previously characterized. However, among them, dendrimer 1 is the only one outperforming all these compounds in terms of 2PA brightness and 2PA oxygen sensitization. Thus, the new type of connector (or dendrimeric node) introduced in 1 appears to be quite appealing for the design of photosensitizers aimed at theranostic uses in the future.
IMPORTANCE Prenatal folic acid supplements reduce the risk of neural tube defects in children, but it has not been determined whether they protect against other neurodevelopmental disorders. ...OBJECTIVE To examine the association between maternal use of prenatal folic acid supplements and subsequent risk of autism spectrum disorders (ASDs) (autistic disorder, Asperger syndrome, pervasive developmental disorder–not otherwise specified PDD-NOS) in children. DESIGN, SETTING, AND PATIENTS The study sample of 85 176 children was derived from the population-based, prospective Norwegian Mother and Child Cohort Study (MoBa). The children were born in 2002-2008; by the end of follow-up on March 31, 2012, the age range was 3.3 through 10.2 years (mean, 6.4 years). The exposure of primary interest was use of folic acid from 4 weeks before to 8 weeks after the start of pregnancy, defined as the first day of the last menstrual period before conception. Relative risks of ASDs were estimated by odds ratios (ORs) with 95% CIs in a logistic regression analysis. Analyses were adjusted for maternal education level, year of birth, and parity. MAIN OUTCOME MEASURE Specialist-confirmed diagnosis of ASDs. RESULTS At the end of follow-up, 270 children in the study sample had been diagnosed with ASDs: 114 with autistic disorder, 56 with Asperger syndrome, and 100 with PDD-NOS. In children whose mothers took folic acid, 0.10% (64/61 042) had autistic disorder, compared with 0.21% (50/24 134) in those unexposed to folic acid. The adjusted OR for autistic disorder in children of folic acid users was 0.61 (95% CI, 0.41-0.90). No association was found with Asperger syndrome or PDD-NOS, but power was limited. Similar analyses for prenatal fish oil supplements showed no such association with autistic disorder, even though fish oil use was associated with the same maternal characteristics as folic acid use. CONCLUSIONS AND RELEVANCE Use of prenatal folic acid supplements around the time of conception was associated with a lower risk of autistic disorder in the MoBa cohort. Although these findings cannot establish causality, they do support prenatal folic acid supplementation.
Emotional intelligence (EI) is the ability to recognize, understand, and manage emotions in yourself and in others. EI has long been recognized as a critical component for individual and ...organizational success within the business realm, and there is emerging evidence that enhancing EI is equally important in the medical setting. EI can improve interpersonal communications, enable constructive conflict resolution, and promote a culture of professionalism. As healthcare becomes increasingly team-based, proficiency in EI will be required to build consensus among multidisciplinary stakeholders, and effect change in attitudes and behaviors that result in improved patient safety and clinical outcomes. Based on the existing literature and the authors' experiences, these 12 tips provide practical suggestions on how to introduce EI into a medical curriculum. These tips have broad applicability, and can be implemented in courses on topics such as professionalism, leadership development, empathy, patient safety, or wellness.
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Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Star-shaped hydrophobic porphyrins, acting as powerful fluorescent two-photon photosensitizers for oxygen in organic solvents, can easily be loaded into PMLABe polymeric nanoparticles at various ...concentrations. In this contribution, the performance of these porphyrin-containing nanoparticles in terms of photodynamic therapy (PDT) is compared to those of the corresponding water-soluble porphyrin analogues when irradiated in MCF-7 cancer cells. While quite promising results are obtained for performing PDT with these nanoparticles, validating this approach as a mean for using more easily accessible and less expensive photosensitizers, from a synthetic perspective, we also show that their luminescence can still be used for bioimaging purposes in spite of their confinement in the nanoparticles, validating also the use of these nano-objects for theranostic purposes.
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