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1.
JCO Oncol Pract ; : OP2300356, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564704

RESUMO

PURPOSE: To establish thresholds in the Patient-Reported Outcomes Measurement Information System (PROMIS) pain interference, physical function, fatigue, and depression scores on the basis of their association with subsequent use of the emergency department (ED) or urgent care by people diagnosed with cancer. METHODS: Retrospective data from 952 people seen at Henry Ford Cancer and insured through the Health Alliance Plan were analyzed using generalized linear mixed-effects models. The log odds of ED or urgent care use during 14 or 30 days after each patient-reported outcome (PRO) assessment were related to PRO scores, while adjusting for comorbidity, sociodemographic, and tumor characteristics. RESULTS: Pain interference and physical function were associated with subsequent ED or urgent care visits, but fatigue and depression were not, and the results for 14- and 30-day visits were similar. Thresholds anchored in the likelihood of these visits differed according to cancer stage. For people with advanced cancer, a pain interference score of 60 or higher (odds ratio [OR] 3.75, [95% CI, 1.53 to 7.87]) and a physical function score lower than 40 (OR 2.94, [95% CI, 1.22 to 7.06]) produced the largest ORs with narrowest CIs for 30-day visits. For people with nonadvanced cancer, the thresholds of 65 for pain interference (OR 2.64, [95% CI, 1.40 to 5.01]) and 35 for physical function (OR 1.87, [95% CI, 1.01 to 3.45]) produced largest ORs with narrowest CIs for 30-day visits. CONCLUSION: These anchor-based thresholds in PROMIS scores can inform clinicians' actions with the goal of preventing ED or urgent care visits.

3.
bioRxiv ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38559011

RESUMO

Growing evidence supports a role for versican as an important component of the inflammatory response, with both pro- and anti-inflammatory roles depending on the specific context of the system or disease under investigation. Our goal is to understand the regulation of macrophage-derived versican and the role it plays in innate immunity. In previous work, we showed that LPS triggers a signaling cascade involving TLR4, the Trif adaptor, type I interferons, and the type I interferon receptor, leading to increased versican expression by macrophages. In the present study, we used a combination of chromatin immunoprecipitation, siRNA, chemical inhibitors, and mouse model approaches to investigate the regulatory events downstream of the type I interferon receptor to better define the mechanism controlling versican expression. Results indicate that transcriptional regulation by canonical type I interferon signaling via the heterotrimeric transcription factor, ISGF3, controls versican expression in macrophages exposed to LPS. This pathway is not dependent on MAPK signaling, which has been shown to regulate versican expression in other cell types. The stability of versican mRNA may also contribute to prolonged versican expression in macrophages. These findings strongly support a role for macrophage-derived versican as a type I interferon-stimulated gene and further our understanding of versican's role in regulating inflammation.

5.
Scand J Immunol ; 99(5): e13359, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38605527

RESUMO

Chlamydia trachomatis infection is the leading cause of bacterial urogenital infection and has been demonstrated to drive inflammation and scarring of the reproductive tract. Recent studies have identified key triggers of proinflammatory adaptive immune responses driven by innate leukocytes and epithelia driving immunopathology. Utilizing chimeric mouse models, we investigated the definitive source and role of IL17 and IL17 signalling receptors during early Chlamydia muridarum infection of the female urogenital tract. Bone marrow transplants from wild-type (WT) and IL17A-/- mice to recipients demonstrated equivocal infection kinetics in the reproductive tract, but interestingly, adoptive transfer of IL17A-/- immune cells to WT recipients resulted in no infertility, suggesting a haematopoietic (as opposed to tissue) source of IL17 driving immunopathology. To further delineate the role of IL17 in immunopathology, we infected WT and IL17 receptor A (IL17RA)-/- female mice and observed a significant reduction in immunopathology in IL17RA-/- mice. WT bone marrow transplants to IL17RA-/- recipient mice prevented hydrosalpinx, suggesting signalling through IL17RA drives immunopathology. Furthermore, early chemical inhibition of IL17 signalling significantly reduced hydrosalpinx, suggesting IL17 acts as an innate driver of disease. Early during the infection, IL17 was produced by γδ T cells in the cervico-vagina, but more importantly, by neutrophils at the site of infertility in the oviducts. Taken together, these data suggest innate production of IL17 by haematopoietic leukocytes drives immunopathology in the epithelia during early C. muridarum infection of the female reproductive tract.


Assuntos
Infecções por Chlamydia , Chlamydia muridarum , Transplante de Células-Tronco Hematopoéticas , Infecções do Sistema Genital , Feminino , Animais , Camundongos , Interleucina-17 , Infecções do Sistema Genital/microbiologia , Infecções do Sistema Genital/patologia , Infecções por Chlamydia/microbiologia , Infecções por Chlamydia/prevenção & controle , Genitália/patologia , Camundongos Endogâmicos C57BL
6.
Transplant Rev (Orlando) ; 38(3): 100853, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38581881

RESUMO

Hypothermic Oxygenated machine PErfusion (HOPE) has recently emerged as a preservation technique which can reduce ischemic injury and improve clinical outcomes following liver transplantation. First developed with the advent solid organ transplantation techniques, hypothermic machine perfusion largely fell out of favour following the development of preservation solutions which can satisfactorily preserve grafts using the cheap and simple method, static cold storage (SCS). However, with an increasing need to develop techniques to reduce graft injury and better utilise marginal and donation after circulatory death (DCD) grafts, HOPE has emerged as a relatively simple and safe technique to optimise clinical outcomes following liver transplantation. Perfusing the graft with cold, acellular, oxygenated perfusate either via the portal vein (PV) alone, or via both the PV and hepatic artery (HA), HOPE is generally commenced for a period of 1-2 h immediately prior to implantation. The technique has been validated by multiple randomised control trials, and pre-clinical evidence suggests HOPE primarily reduces graft injury by decreasing the accumulation of harmful mitochondrial intermediates, and subsequently, the severity of post-reperfusion injury. HOPE can also facilitate real time graft assessment, most notably via the measurement of flavin mononucleotide (FMN) in the perfusate, allowing transplant teams to make better informed clinical decisions prior to transplantation. HOPE may also provide a platform to administer novel therapeutic agents to ex situ organs without risk of systemic side effects. As such, HOPE is uniquely positioned to revolutionise how liver transplantation is approached and facilitate optimised clinical outcomes for liver transplant recipients.

7.
PLoS One ; 19(4): e0302009, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38620042

RESUMO

Phytoliths of biogenic silica play a vital role in the silicon biogeochemical cycle and occlude a fraction of organic carbon. The location, chemical speciation, and quantification of this carbon within phytoliths have remained elusive due to limited direct experimental evidence. In this work, phytoliths (bilobate morphotype) from the sugarcane stalk epidermis are sectioned with a focused ion beam to produce lamellas (≈10 × 10 µm2 size, <500 nm thickness) and probed by synchrotron scanning transmission X-ray microspectroscopy (≈100-200 nm pixel size; energies near the silicon and carbon K-absorption edges). Analysis of the spectral image stacks reveals the complementarity of the silica and carbon spatial distributions, with carbon found at the borders of the lamellas, in islands within the silica, and dispersed in extended regions that can be described as a mixed silica-carbonaceous matrix. Carbon spectra are assigned mainly to lignin-like compounds as well as to proteins. Carbon contents of 3-14 wt.% are estimated from the spectral maps of four distinct phytolith lamellas. The results provide unprecedented spatial and chemical information on the carbon in phytoliths obtained without interference from wet-chemical digestion.


Assuntos
Dióxido de Silício , Silício , Dióxido de Silício/química , Raios X , Carbono/análise , Síncrotrons
8.
J Med Chem ; 67(8): 6456-6494, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38574366

RESUMO

Dysregulation of IL17A drives numerous inflammatory and autoimmune disorders with inhibition of IL17A using antibodies proven as an effective treatment. Oral anti-IL17 therapies are an attractive alternative option, and several preclinical small molecule IL17 inhibitors have previously been described. Herein, we report the discovery of a novel class of small molecule IL17A inhibitors, identified via a DNA-encoded chemical library screen, and their subsequent optimization to provide in vivo efficacious inhibitors. These new protein-protein interaction (PPI) inhibitors bind in a previously undescribed mode in the IL17A protein with two copies binding symmetrically to the central cavities of the IL17A homodimer.


Assuntos
DNA , Descoberta de Drogas , Interleucina-17 , Bibliotecas de Moléculas Pequenas , Interleucina-17/metabolismo , Interleucina-17/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , DNA/metabolismo , DNA/química , Humanos , Animais , Relação Estrutura-Atividade , Ligação Proteica , Camundongos
9.
Cell Rep ; : 114102, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38636518

RESUMO

Although dysregulated cholesterol metabolism predisposes aging tissues to inflammation and a plethora of diseases, the underlying molecular mechanism remains poorly defined. Here, we show that metabolic and genotoxic stresses, convergently acting through liver X nuclear receptor, upregulate CD38 to promote lysosomal cholesterol efflux, leading to nicotinamide adenine dinucleotide (NAD+) depletion in macrophages. Cholesterol-mediated NAD+ depletion induces macrophage senescence, promoting key features of age-related macular degeneration (AMD), including subretinal lipid deposition and neurodegeneration. NAD+ augmentation reverses cellular senescence and macrophage dysfunction, preventing the development of AMD phenotype. Genetic and pharmacological senolysis protect against the development of AMD and neurodegeneration. Subretinal administration of healthy macrophages promotes the clearance of senescent macrophages, reversing the AMD disease burden. Thus, NAD+ deficit induced by excess intracellular cholesterol is the converging mechanism of macrophage senescence and a causal process underlying age-related neurodegeneration.

10.
Vet Dermatol ; 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616572

RESUMO

BACKGROUND: Perianal fistulas are painful ulcers or sinus tracts that disproportionately affect German shepherd dogs and are proposed as a spontaneous animal model of fistulising Crohn's disease. OBJECTIVES: To characterise the rectal and cutaneous microbiota in German shepherd dogs with perianal fistulas and to investigate longitudinal shifts with lesion resolution during immunomodulatory therapy. ANIMALS: Eleven German shepherd dogs with perianal fistulas and 15 healthy German shepherd dogs. MATERIALS AND METHODS: Affected dogs were evaluated and swabbed at three visits, 30 days apart, while undergoing treatment with ciclosporin and ketoconazole. Healthy German shepherd dogs were contemporaneously sampled. Sites included the rectum, perianal skin and axilla. The microbiome was evaluated following sequencing of the V4 hypervariable region of the 16S ribosomal RNA (rRNA) gene. RESULTS: Alpha diversity was not significantly different between healthy and affected dogs at each of the three body sites (p > 0.5), yet rectal and perianal beta diversities from affected dogs differed significantly from those of healthy dogs at Day 0 (p = 0.004). Rectal and perianal relative abundance of Prevotella spp. increased and perianal Staphylococcus spp. relative abundance decreased in affected dogs over time, coincident with lesion resolution. CONCLUSIONS AND CLINICAL RELEVANCE: Changes in lesional cutaneous and rectal microbiota occur in German shepherd dogs with perianal fistulas and shift over time with lesion resolution during immunomodulatory therapy. Further investigations of the role of cutaneous and enteric microbiota in the pathogenesis of perianal fistulas, and whether manipulation of microbial populations may ameliorate disease, are needed.

11.
J Clin Med ; 13(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38592199

RESUMO

Background: One of the goals of the Multi-site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM) study was to evaluate whether clinicians experienced in diagnosing and caring for patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) recognized the same clinical entity. Methods: We enrolled participants from seven specialty clinics in the United States. We used baseline data (n = 465) on standardized questions measuring general clinical characteristics, functional impairment, post-exertional malaise, fatigue, sleep, neurocognitive/autonomic symptoms, pain, and other symptoms to evaluate whether patient characteristics differed by clinic. Results: We found few statistically significant and no clinically significant differences between clinics in their patients' standardized measures of ME/CFS symptoms and function. Strikingly, patients in each clinic sample and overall showed a wide distribution in all scores and measures. Conclusions: Illness heterogeneity may be an inherent feature of ME/CFS. Presenting research data in scatter plots or histograms will help clarify the challenge. Relying on case-control study designs without subgrouping or stratification of ME/CFS illness characteristics may limit the reproducibility of research findings and could obscure underlying mechanisms.

12.
J Psychiatr Res ; 174: 46-53, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38613942

RESUMO

Many confirmatory factor analyses (CFA) have examined the structure of posttraumatic stress disorder (PTSD) with some suggesting increased complexity (i.e., 6+ factors), while others suggesting a more refined structure (i.e., 2-factors). These competing PTSD structures may be due to conflation of non-trauma specific symptoms that have been added overtime. However, none of these studies examined if all symptoms being examined are specific to PTSD or potentially more related to general distress and psychopathology. The current study re-evaluated the structure of PTSD using bifactor exploratory factor analysis (EFA) to identify the construct's core symptoms. Data for EFA models were taken from a sample of Veterans (N = 694) attending outpatient therapy for PTSD and were cross-validated using CFA in a sample of 297 Veterans attending residential treatment. Clinician Administered PTSD Scale for DSM-5 (CAPS-5) at pre-treatment was used across sample. Factor analyses resulted in a 2-factor, bifactor model comprised of eight total items. Model fit was robust, RMSEA = 0 [0.000, 0.036]; robust CFI = 1; robust TLI = 1.017. The bifactor analytic approach captured what might be the core structure of PTSD, which were pathognomonic symptoms of PTSD (Factor one). A distinct second factor related to depression was also found. In identifying this structure, the model eliminates redundancies and lesser performing items and differentiates depressive reactions as potentially distinct and separate. Overall, these findings may assist in future research of PTSD by determining the unique elements of the construct within a veteran sample versus associated features, general psychological distress, and comorbid psychopathology.

13.
Am Fam Physician ; 109(4): 350-359, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38648834

RESUMO

Lumbar spinal stenosis is a clinical syndrome that affects more than 200,000 people in the United States annually. It is a common cause of chronic insidious low back pain, especially in older patient populations (mean age = 64 years). Lumbar spinal stenosis is a degenerative condition of the spine leading to narrowing in the spaces around the neurovascular bundles and the classic symptom of low back pain that radiates to the buttocks and lower extremities bilaterally. It is typically a progressive waxing and waning process that may deteriorate over years. The pain is typically burning or cramping, which worsens with standing and walking and improves with bending forward or sitting. Magnetic resonance imaging is the recommended diagnostic test because it allows cross-sectional measurement of the spinal canal. Options for nonsurgical management include physical therapy, exercise programs, spinal injections with and without corticosteroids, chiropractic treatment, osteopathic manipulation, acupuncture, and lifestyle modifications; however, few of these treatments have high-quality randomized trials demonstrating effectiveness. Surgery may be considered if nonsurgical management is ineffective.

14.
FEMS Microbiol Ecol ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38650064

RESUMO

With the increase in crude oil transport throughout Canada, the potential for spills into freshwater ecosystems has increased and additional research is needed in these sensitive environments. Large enclosures erected in a lake were used as mesocosms for this controlled experimental dilbit (diluted bitumen) spill under ambient environmental conditions. The microbial response to dilbit, the efficacy of standard remediation protocols on different shoreline types commonly found in Canadian freshwater lakes, including a testing of a shoreline washing agent were all evaluated. We found that the native microbial community did not undergo any significant shifts in composition after exposure to dilbit or the ensuing remediation treatments. Regardless of the treatment, sample type (soil, sediment, or water), or type of associated shoreline, the community remained relatively consistent over a 3-month monitoring period. Following this, metagenomic analysis of polycyclic aromatic and alkane hydrocarbon degradation mechanisms also showed that while many key genes identified in PAH and alkane biodegradation were present, their abundance did not change significantly over the course of the experiment. These results showed that the native microbial community present in a pristine freshwater lake has the prerequisite mechanisms for hydrocarbon degradation in place, and combined with standard remediation practices in use in Canada, has the genetic potential and resilience to potentially undertake bioremediation.

15.
FEMS Microbiol Ecol ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38650065

RESUMO

The overall impact of a crude oil spill into a pristine freshwater environment in Canada is largely unknown. To evaluate the impact on the native microbial community, a large-scale in situ model experimental spill was conducted to assess the potential role of the natural community to attenuate hydrocarbons. A small volume of conventional heavy crude oil (CHV) was introduced within contained mesocosm enclosures deployed on the shoreline of a freshwater lake. The oil was left to interact with the shoreline for 72 h and then free-floating oil was recovered using common oil spill response methods (i.e. freshwater flushing and capture on oleophilic absorptive media). Residual PAH concentrations returned to near pre-oiling concentrations within 2 months, while the microbial community composition across the water, soil, and sediment matrices of the enclosed oligotrophic freshwater ecosystems did not shift significantly over this period. Metagenomic analysis revealed key polycyclic aromatic and alkane degradation mechanisms also did not change in their relative abundance over the monitoring period. These trends suggest that for small spills (<2 L of oil per 15 m2 of surface freshwater), physical oil recovery reduces PAH concentrations to levels tolerated by the native microbial community. Additionally, the native microbial community present in the monitored pristine freshwater ecosystem possesses the appropriate hydrocarbon degradation mechanisms without prior challenge by hydrocarbon substrates. This study corroborated trends found previously (Kharey et al. 2024) toward freshwater hydrocarbon degradation in an environmentally relevant scale and conditions on the tolerance of residual hydrocarbons in situ.

16.
Chem Sci ; 15(12): 4478-4488, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516070

RESUMO

The catalytic reduction of dioxygen (O2) is important in biological energy conversion and alternative energy applications. In comparison to Fe- and Co-based systems, examples of catalytic O2 reduction by homogeneous Mn-based systems is relatively sparse. Motivated by this lack of knowledge, two Mn-based catalysts for the oxygen reduction reaction (ORR) containing a bipyridine-based non-porphyrinic ligand framework have been developed to evaluate how pendent proton donor relays alter activity and selectivity for the ORR, where Mn(p-tbudhbpy)Cl (1) was used as a control complex and Mn(nPrdhbpy)Cl (2) contains a pendent -OMe group in the secondary coordination sphere. Using an ammonium-based proton source, N,N'-diisopropylethylammonium hexafluorophosphate, we analyzed catalytic activity for the ORR: 1 was found to be 64% selective for H2O2 and 2 is quantitative for H2O2, with O2 binding to the reduced Mn(ii) center being the rate-determining step. Upon addition of the conjugate base, N,N'-diisopropylethylamine, the observed catalytic selectivity of both 1 and 2 shifted to H2O as the primary product. Interestingly, while the shift in selectivity suggests a change in mechanism for both 1 and 2, the catalytic activity of 2 is substantially enhanced in the presence of base and the rate-determining step becomes the bimetallic cleavage of the O-O bond in a Mn-hydroperoxo species. These data suggest that the introduction of pendent relay moieties can improve selectivity for H2O2 at the expense of diminished reaction rates from strong hydrogen bonding interactions. Further, although catalytic rate enhancements are observed with a change in product selectivity when base is added to buffer proton activity, the pendent relays stabilize dimer intermediates, limiting the maximum rate.

17.
Sensors (Basel) ; 24(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38544160

RESUMO

A new scheme presents MEMS-based LiDAR with synchronized dual-laser beams for detection range enhancement and precise point-cloud data without using higher laser power. The novel MEMS-based LiDAR module uses the principal laser light to build point-cloud data. In addition, an auxiliary laser light amplifies the single-noise ratio to enhance the detection range. This LiDAR module exhibits the field of view (FOV), angular resolution, and maximum detection distance of 45° (H) × 25° (V), 0.11° (H) × 0.11° (V), and 124 m, respectively. The maximum detection distance is enhanced by 16% from 107 m to 124 m with a laser power of 1 W and an additional auxiliary laser power of 0.355 W. Furthermore, the simulation results show that the maximum detection distance can be up to 300 m with laser power of 8 W and only 6 W if the auxiliary laser light of 2.84 W is used, which is 35.5% of the laser power. This result indicates that the synchronized dual-laser beams can achieve long detection distance and reduce laser power 30%, hence saving on the overall laser system costs. Therefore, the proposed LiDAR module can be applied for a long detection range in autonomous vehicles without requiring higher laser power if it utilizes an auxiliary laser light.

18.
AEM Educ Train ; 8(2): e10963, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38525365

RESUMO

Objectives: There is no standardized protocol for performing educational point-of-care ultrasonography (POCUS) that addresses patient-centered ethical issues such as obtaining informed consent. This study sought to define principles for ethical application of educational POCUS and develop consensus-based best practice guidance. Methods: A questionnaire was developed by a trained ethicist after literature review with the help of a medical librarian. A diverse panel including experts in medical education, law, and bioethics; medical trainees; and individuals with no medical background was convened. The panel voted on their level of agreement with ethical principles and degree of appropriateness of behaviors in three rounds of a modified Delphi process. A high level of agreement was defined as 80% or greater consensus. Results: Panelists voted on 38 total items: 15 related to the patient consent and selection process, eight related to practices while performing educational POCUS, and 15 scenarios involving POCUS application. A high level of agreement was achieved for 13 items related to patient consent and selection, eight items related to performance practices, and 10 scenarios of POCUS application. Conclusions: Based on expert consensus, ethical best practices include obtaining informed consent before performing educational POCUS, allowing patients to decline educational POCUS, informing patients the examination is not intended to be a part of their medical evaluation and is not billed, using appropriate draping techniques, maintaining a professional environment, and disclosing incidental findings in coordination with the primary team caring for the patient. These practices could be implemented at institutions to encourage ethical use of educational POCUS when training physicians, fellows, residents, and medical students.

19.
Pharmaceutics ; 16(3)2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38543278

RESUMO

Pre-exposure prophylaxis (PrEP) with a weekly oral regimen of antiretroviral drugs could be a suitable preventative option for individuals who struggle with daily PrEP or prefer not to use long-acting injectables. We assessed in macaques the efficacy of weekly oral tenofovir alafenamide (TAF) at doses of 13.7 or 27.4 mg/kg. Macaques received weekly oral TAF for six weeks and were exposed twice-weekly to SHIV vaginally or rectally on day 3 and 6 after each dose. Median TFV-DP levels in PBMCs following the 13.7 mg/kg dose were 3110 and 1137 fmols/106 cells on day 3 and 6, respectively. With the 27.4 mg/kg dose, TFV-DP levels were increased (~2-fold) on day 3 and 6 (6095 and 3290 fmols/106 cells, respectively). Both TAF doses (13.7 and 27.4 mg/kg) conferred high efficacy (94.1% and 93.9%, respectively) against vaginal SHIV infection. Efficacy of the 27.4 mg/kg dose against rectal SHIV infection was 80.7%. We estimate that macaque doses of 13.7 and 27.4 mg/kg are equivalent to approximately 230 and 450 mg of TAF in humans, respectively. Our findings demonstrate the effectiveness of a weekly oral PrEP regimen and suggest that a clinically achievable oral TAF dose could be a promising option for non-daily PrEP.

20.
J Org Chem ; 89(7): 4657-4672, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38530877

RESUMO

A straightforward route to 1,4-dihydropyrrolo[3,2-b]pyrroles comprised of two electron-withdrawing quinoline or tetrazolo[1,5-a]quinoline scaffolds has been developed. The versatile multicomponent reaction affording 1,4-dihydropyrrolo[3,2-b]pyrroles combined with intramolecular direct arylation enables assembly of these products in just three steps from anilines with overall yields exceeding 30%. The planarized, ladder-type heteroacenes possess up to 14 conjugated rings. These nominally quadrupolar materials exhibit efficient fluorescence with wavelengths spanning most of the visible spectrum from green-yellow for the dyes possessing biaryl bridges and orange-red for the fully fused systems. In many cases, the fluorescence quantum yields are large, the solvatofluorochromic effects are strong, and the fluorescence is maintained even in crystalline state. Analysis of the electronic structure of these molecular architectures using quantum chemical methods suggests that the character and position of the flanking heterocycle determine the shape of HOMO and LUMO and their extension to N-aryl substituents, influencing the values of molar absorption coefficient. An experimental study of the two-photon absorption (2PA) properties has revealed that it occurs in the 700-800 nm range with apparent deviation from the Laporte parity selection rule, which may be attributed to Hertzberg-Teller contribution to vibronically allowed 2PA transition.

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