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1.
Dalton Trans ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32065186

RESUMO

Two novel rhenium(i) tricarbonyl complexes of general formula fac-[Re(N^C:)(CO)3X] are herein presented, where N^C: is the pyridoannelated N-heterocyclic carbene (NHC) arising from 2-(2-pyridinyl)imidazo[1,5-a]pyridinium hexafluorophosphate proligand, namely [pyipy]PF6, and X being Cl and Br. The synthetic pathway is a one-pot reaction that starts from the azolium salt as the NHC source and [Re(CO)5X] to yield the desired charge-neutral fac-[Re(pyipy)(CO)3X] complexes (1-2). Both complexes were thoroughly characterized by spectroscopic, electrochemical, theoretical investigation as well as X-ray diffraction analysis. They display a rather similar electronic absorption spectrum in dilute CH2Cl2 solution, which is characterized by a broad profile extending into the blue region. This lowest-lying absorption band is attributed to a transition with admixed metal-to-ligand charge transfer and intraligand charge transfer (1MLCT/1ILCT) character. Degassed samples of the complexes display moderate (Φ ≈ 1.5%) and long-lived (τ = 12.8-13.4 µs) red photoluminescence with highly structured profile independent of the nature of the ancillary halogen ligand and little sensitivity to the solvent polarity, highlighting the markedly different nature of the emitting excited state in comparison with the lowest-lying absorption. Indeed, photoluminescence is ascribed to a long-lived excited state with metal-perturbed triplet ligand-centred (3LC) character as supported by both experimental and density functional theory (DFT) investigations.

2.
BMJ Open ; 10(1): e033332, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31964673

RESUMO

OBJECTIVES: To assess the prevalence of undiagnosed diabetes and pre-diabetes in the healthy population in the Mollerussa cohort. As a secondary objective, to identify the variables associated with these conditions and to describe the changes in glycaemic status after 1 year of follow-up in subjects with pre-diabetes. DESIGN: Prospective observational cohort study. SETTING: General population from a semi-rural area. PARTICIPANTS: The study included 583 participants without a diagnosis of diabetes recruited between March 2011 and July 2014. RESULTS: The prevalence of undiagnosed diabetes was 20, 3.4% (95% CI 2.6 to 4.2) and that of pre-diabetes was 229, 39.3% (37.3 to 41.3). Among those with pre-diabetes, 18.3% had isolated impaired fasting plasma glucose (FPG) (FPG: 100 to <126 mg/dL), 58.1% had isolated impaired glycated haemoglobin (HbA1c) (HbA1c 5.7 to <6.5) and 23.6% fulfilled both criteria. Follow-up data were available for 166 subjects; 41.6%(37.8 to 45.4) returned to normoglycaemia, 57.6% (57.8 to 61.4) persisted in pre-diabetes and 0.6% (0 to 1.2) progressed to diabetes. Individuals with pre-diabetes had worse cardiometabolic risk profiles and sociodemographic features than normoglycaemic subjects. In the logistic regression model, variables significantly associated with pre-diabetes were older age (OR; 95% CI) (1.033; 1.011 to 1.056), higher physical activity (0.546; 0.360 to 0.827), body mass index (1.121; 1.029 to 1.222) and a family history of diabetes (1.543; 1.025 to 2.323). The variables significantly associated with glycaemic normalisation were older age (0.948; 0.916 to 0.982) and body mass index (0.779; 0.651 to 0.931). CONCLUSIONS: Among adults in our region, the estimated prevalence of undiagnosed diabetes was 3.4% and that of pre-diabetes was 39.3%. After a 1-year follow-up, a small proportion of subjects (0.6%) with pre-diabetes progressed to diabetes, while a high proportion (41.6%) returned to normoglycaemia. Individuals with pre-diabetes who returned to normoglycaemia were younger and had a lower body mass index.

3.
Dalton Trans ; 48(29): 10915-10926, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31149683

RESUMO

Ligand field enhancing N-heterocyclic carbene (NHC) ligands were recently shown to prevent photo-induced spin crossover in Fe(ii) complexes due to their intricate effects on the electronic excited state structure. Due to their pico- to nanosecond lifetimes, these complexes are now good candidates for photo-sensitizing applications. Herein we report the synthesis and photophysical characterization of a new family of homoleptic Fe(ii) complexes with C^N^C ligands involving diazines as the central N-heteroaromatic ligand. For these four carbene bond complexes, ultrafast transient absorption spectroscopy revealed a significant improvement of the excited-state lifetime. A record 32 ps lifetime was measured for a complex bearing a ligand combining a π-deficient pyrazine nucleus and a benzimidazolylidene as NHC. When compared to other azine-based ligands investigated, we argue that the lifetimes are modulated by a small excited state barrier expressing the ability of the ligand to reach the Fe-N distance needed for internal conversion to the ground state.

4.
Inorg Chem ; 58(8): 5069-5081, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30950264

RESUMO

The control of photophysical properties of iron complexes and especially of their excited states decay is a great challenge in the search for sustainable alternatives to noble metals in photochemical applications. Herein we report the synthesis and investigations of the photophysics of mer and fac iron complexes bearing bidentate pyridyl-NHC ligands, coordinating the iron with three ligand-field-enhancing carbene bonds. Ultrafast transient absorption spectroscopy reveals two distinct excited state populations for both mer and fac forms, ascribed to the populations of the T1 and the T2 states, respectively, which decay to the ground state via parallel pathways. We find 3-4 ps and 15-20 ps excited-state lifetimes, with respective amplitudes depending on the isomer. The longer lifetime exceeds the one reported for iron complexes with tridentate ligands analogues involving four iron-carbene bonds. By combining experimental and computational results, a mechanism based on the differential trapping of the triplet states in spin-crossover regions is proposed for the first time to explain the impact of the fac/ mer isomerism on the overall excited-state lifetimes. Our results clearly highlight the impact of bidentate pyridyl-NHC ligands on the photophysics of iron complexes, especially the paramount role of fac/ mer isomerism in modulating the overall decay process, which can be potentially exploited in the design of new Fe(II)-based photoactive compounds.

5.
JCI Insight ; 4(1)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30626756

RESUMO

Podocyte injury is central to many forms of kidney disease, but transcriptional signatures reflecting podocyte injury and compensation mechanisms are challenging to analyze in vivo. Human kidney organoids derived from pluripotent stem cells (PSCs), a potentially new model for disease and regeneration, present an opportunity to explore the transcriptional plasticity of podocytes. Here, transcriptional profiling of more than 12,000 single cells from human PSC-derived kidney organoid cultures was used to identify robust and reproducible cell lineage gene expression signatures shared with developing human kidneys based on trajectory analysis. Surprisingly, the gene expression signature characteristic of developing glomerular epithelial cells was also observed in glomerular tissue from a kidney disease cohort. This signature correlated with proteinuria and inverse eGFR, and it was confirmed in an independent podocytopathy cohort. Three genes in particular were further characterized as potentially novel components of the glomerular disease signature. We conclude that cells in human PSC-derived kidney organoids reliably recapitulate the developmental transcriptional program of podocytes and other cell lineages in the human kidney and that transcriptional profiles seen in developing podocytes are reactivated in glomerular disease. Our findings demonstrate an approach to identifying potentially novel molecular programs involved in the pathogenesis of glomerulopathies.

6.
Front Physiol ; 9: 1588, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30483151

RESUMO

Classically, trophic factors are considered as proteins which support neurons in their growth, survival, and differentiation. However, most neurotrophic factors also have important functions outside of the nervous system. Especially essential renal growth and differentiation regulators are glial cell line-derived neurotrophic factor (GDNF), bone morphogenetic proteins (BMPs), and fibroblast growth factors (FGFs). Here we discuss how trophic factor-induced signaling contributes to the control of ureteric bud (UB) branching morphogenesis and to maintenance and differentiation of nephrogenic mesenchyme in embryonic kidney. The review includes recent advances in trophic factor functions during the guidance of branching morphogenesis and self-renewal versus differentiation decisions, both of which dictate the control of kidney size and nephron number. Creative utilization of current information may help better recapitulate renal differentiation in vitro, but it is obvious that significantly more basic knowledge is needed for development of regeneration-based renal therapies.

7.
Proc Natl Acad Sci U S A ; 115(45): E10605-E10614, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30348760

RESUMO

Hox5 genes (Hoxa5, Hoxb5, Hoxc5) are exclusively expressed in the lung mesenchyme during embryogenesis, and the most severe phenotypes result from constitutive loss of function of all three genes. Because Hox5 triple null mutants exhibit perinatal lethality, the contribution of this paralogous group to postembryonic lung development is unknown. Intriguingly, expression of all three Hox5 genes peaks during the first 2 weeks after birth, reaching levels far exceeding those measured at embryonic stages, and surviving Hoxa5 single and Hox5 AabbCc compound mutants exhibit defects in the localization of alveolar myofibroblasts. To define the contribution of the entire Hox5 paralogous group to this process, we generated an Hoxa5 conditional allele to use with our existing null alleles for Hoxb5 and Hoxc5 Postnatally, mesenchymal deletion of Hoxa5 in an Hoxb5/Hoxc5 double-mutant background results in severe alveolar simplification. The elastin network required for alveolar formation is dramatically disrupted in Hox5 triple mutants, while the basal lamina, interstitial matrix, and fibronectin are normal. Alveolar myofibroblasts remain Pdgfrα+/SMA+ double positive and present in normal numbers, indicating that the irregular elastin network is not due to fibroblast differentiation defects. Rather, we observe that SMA+ myofibroblasts of Hox5 triple mutants are morphologically abnormal both in vivo and in vitro with highly reduced adherence to fibronectin. This loss of adhesion is a result of loss of the integrin heterodimer Itga5b1 in mutant fibroblasts. Collectively, these data show an important role for Hox5 genes in lung fibroblast adhesion necessary for proper elastin network formation during alveologenesis.


Assuntos
Adesão Celular , Elastina/metabolismo , Genes Homeobox , Miofibroblastos/citologia , Alvéolos Pulmonares/citologia , Alelos , Animais , Dimerização , Regulação da Expressão Gênica no Desenvolvimento , Integrina alfa5/metabolismo , Integrina beta1/metabolismo , Camundongos , Mutação , Miofibroblastos/metabolismo , Alvéolos Pulmonares/metabolismo
8.
Development ; 145(16)2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-30166318

RESUMO

The mammalian kidney develops through reciprocal interactions between the ureteric bud and the metanephric mesenchyme to give rise to the entire collecting system and the nephrons. Most of our knowledge of the developmental regulators driving this process arises from the study of gene expression and functional genetics in mice and other animal models. In order to shed light on human kidney development, we have used single-cell transcriptomics to characterize gene expression in different cell populations, and to study individual cell dynamics and lineage trajectories during development. Single-cell transcriptome analyses of 6414 cells from five individual specimens identified 11 initial clusters of specific renal cell types as defined by their gene expression profile. Further subclustering identifies progenitors, and mature and intermediate stages of differentiation for several renal lineages. Other lineages identified include mesangium, stroma, endothelial and immune cells. Novel markers for these cell types were revealed in the analysis, as were components of key signaling pathways driving renal development in animal models. Altogether, we provide a comprehensive and dynamic gene expression profile of the developing human kidney at the single-cell level.


Assuntos
Linhagem da Célula/fisiologia , Feto/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Rim/embriologia , Transdução de Sinais/fisiologia , Células-Tronco/metabolismo , Animais , Feto/citologia , Perfilação da Expressão Gênica , Humanos , Rim/citologia , Camundongos , Células-Tronco/citologia
9.
Stem Cell Reports ; 11(4): 912-928, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30220628

RESUMO

The in vivo niche and basic cellular properties of nephron progenitors are poorly described. Here we studied the cellular organization and function of the MAPK/ERK pathway in nephron progenitors. Live-imaging of ERK activity by a Förster resonance energy transfer biosensor revealed a dynamic activation pattern in progenitors, whereas differentiating precursors exhibited sustained activity. Genetic experiments demonstrate that MAPK/ERK activity controls the thickness, coherence, and integrity of the nephron progenitor niche. Molecularly, MAPK/ERK activity regulates niche organization and communication with extracellular matrix through PAX2 and ITGA8, and is needed for CITED1 expression denoting undifferentiated status. MAPK/ERK activation in nephron precursors propels differentiation by priming cells for distal and proximal fates induced by the Wnt and Notch pathways. Thus, our results demonstrate a mechanism through which MAPK/ERK activity controls both progenitor maintenance and differentiation by regulating a distinct set of targets, which maintain the biomechanical milieu of tissue-residing progenitors and prime precursors for nephrogenesis.


Assuntos
Diferenciação Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Néfrons/citologia , Nicho de Células-Tronco , Células-Tronco/citologia , Animais , Apoptose , Técnicas Biossensoriais , Padronização Corporal , Proliferação de Células , Autorrenovação Celular , Ativação Enzimática , Regulação da Expressão Gênica no Desenvolvimento , Cadeias alfa de Integrinas/metabolismo , Camundongos , Organogênese , Fator de Transcrição PAX2/metabolismo , Células-Tronco/metabolismo
10.
Inorg Chem ; 57(16): 10431-10441, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30063338

RESUMO

The synthesis and the steady-state absorption spectrum of a new pyridine-imidazolylidene Fe(II) complex (Fe-NHC) are presented. A detailed mechanism of the triplet metal-to-ligand charge-transfer states decay is provided on the basis of minimum energy path (MEP) calculations used to connect the lowest-lying singlet, triplet, and quintet state minima. The competition between the different decay pathways involved in the photoresponse is assessed by analyzing the shapes of the obtained potential energy surfaces. A qualitative difference between facial ( fac) and meridional ( mer) isomers' potential energy surface (PES) topologies is evidenced for the first time in iron-based complexes. Indeed, the mer complex shows a steeper triplet path toward the corresponding 3MC minimum, which lies at a lower energy as compared to the fac isomer, thus pointing to a faster triplet decay of the former. Furthermore, while a major role of the metal-centered quintet state population from the triplet 3MC region is excluded, we identify the enlargement of iron-nitrogen bonds as the main normal modes driving the excited-state decay.

11.
Dev Cell ; 46(2): 173-188.e3, 2018 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-30016620

RESUMO

The early midgut undergoes intensive elongation, but the underlying cellular and molecular mechanisms are unknown. The early midgut epithelium is pseudostratified, and its nuclei travel between apical and basal surfaces in concert with cell cycle. Using 3D confocal imaging and 2D live imaging, we profiled behaviors of individual dividing cells. As nuclei migrate apically for mitosis, cells maintain a basal process (BP), which splits but is inherited by only one daughter. After mitosis, some daughters directly use the inherited BP as a "conduit" to transport the nucleus basally, while >50% of daughters generate a new basal filopodium and use it as a path to return the nucleus. Post-mitotic filopodial "pathfinding" is guided by mesenchymal WNT5A. Without WNT5A, some cells fail to tether basally and undergo apoptosis, leading to a shortened midgut. Thus, these studies reveal previously unrecognized strategies for efficient post-mitotic nuclear trafficking, which is critical for early midgut elongation.


Assuntos
Pseudópodes/fisiologia , Proteína Wnt-5a/fisiologia , Animais , Ciclo Celular , Movimento Celular , Núcleo Celular/metabolismo , Sistema Digestório/metabolismo , Fenômenos Fisiológicos do Sistema Digestório , Endoderma , Epitélio/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitose/fisiologia , Proteína Wnt-5a/metabolismo
12.
Beilstein J Org Chem ; 14: 1459-1481, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30013674

RESUMO

Phosphorescent organometallic compounds based on heavy transition metal complexes (TMCs) are an appealing research topic of enormous current interest. Amongst all different fields in which they found valuable application, development of emitting materials based on TMCs have become crucial for electroluminescent devices such as phosphorescent organic light-emitting diodes (PhOLEDs) and light-emitting electrochemical cells (LEECs). This interest is driven by the fact that luminescent TMCs with long-lived excited state lifetimes are able to efficiently harvest both singlet and triplet electro-generated excitons, thus opening the possibility to achieve theoretically 100% internal quantum efficiency in such devices. In the recent past, various classes of compounds have been reported, possessing a beautiful structural variety that allowed to nicely obtain efficient photo- and electroluminescence with high colour purity in the red, green and blue (RGB) portions of the visible spectrum. In addition, achievement of efficient emission beyond such range towards ultraviolet (UV) and near infrared (NIR) regions was also challenged. By employing TMCs as triplet emitters in OLEDs, remarkably high device performances were demonstrated, with square planar platinum(II) complexes bearing π-conjugated chromophoric ligands playing a key role in such respect. In this contribution, the most recent and promising trends in the field of phosphorescent platinum complexes will be reviewed and discussed. In particular, the importance of proper molecular design that underpins the successful achievement of improved photophysical features and enhanced device performances will be highlighted. Special emphasis will be devoted to those recent systems that have been employed as triplet emitters in efficient PhOLEDs.

13.
Kidney Int ; 93(3): 589-598, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29217079

RESUMO

The regulation of final nephron number in the kidney is poorly understood. Cessation of nephron formation occurs when the self-renewing nephron progenitor population commits to differentiation. Transcription factors within this progenitor population, such as SIX2, are assumed to control expression of genes promoting self-renewal such that homozygous Six2 deletion results in premature commitment and an early halt to kidney development. In contrast, Six2 heterozygotes were assumed to be unaffected. Using quantitative morphometry, we found a paradoxical 18% increase in ureteric branching and final nephron number in Six2 heterozygotes, despite evidence for reduced levels of SIX2 protein and transcript. This was accompanied by a clear shift in nephron progenitor identity with a distinct subset of downregulated progenitor genes such as Cited1 and Meox1 while other genes were unaffected. The net result was an increase in nephron progenitor proliferation, as assessed by elevated EdU (5-ethynyl-2'-deoxyuridine) labeling, an increase in MYC protein, and transcriptional upregulation of MYC target genes. Heterozygosity for Six2 on an Fgf20-/- background resulted in premature differentiation of the progenitor population, confirming that progenitor regulation is compromised in Six2 heterozygotes. Overall, our studies reveal a unique dose response of nephron progenitors to the level of SIX2 protein in which the role of SIX2 in progenitor proliferation versus self-renewal is separable.


Assuntos
Proliferação de Células/genética , Autorrenovação Celular/genética , Haploinsuficiência , Proteínas de Homeodomínio/genética , Morfogênese/genética , Néfrons/metabolismo , Células-Tronco/metabolismo , Fatores de Transcrição/genética , Animais , Fatores de Crescimento de Fibroblastos/deficiência , Fatores de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Heterozigoto , Proteínas de Homeodomínio/metabolismo , Camundongos Knockout , Néfrons/embriologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fenótipo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais/genética , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/deficiência
14.
Org Biomol Chem ; 15(40): 8568-8575, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28972609

RESUMO

A selective microwave-assisted mono- and bis-annulation of dialkynyl-N-(het)arylpyrrole derivatives is described. These polycyclic aromatic hydrocarbons (PAHs) have been photophysically and computationally characterized. The mono-annulated systems display interesting charge-transfer properties. By contrast, these properties vanish within the more conjugated bis-annulated compounds.

15.
Chemistry ; 23(70): 17626-17636, 2017 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-28857379

RESUMO

Functional materials that respond to external stimuli are of major current interest. In particular, supramolecular systems that can interact with their surroundings, adapt to environmental changes and evolve with are even more fascinating, yet challenging. Combining the rich physico-chemical properties featured by metal centres with characteristics typical of classical organic polymers, metallopolymers or metallo-supramolecular polymers can be prepared, depending on their static versus dynamic structural features. Additionally, multiple and orthogonal functionalities can be encoded in their chemical structure affording materials with widespread potential applications to be employed as "smart" materials for advanced technologies. In this Concept article, selected examples of metal-containing polymers will be described demonstrating large potentialities of such systems for creating stimuli-responsive materials with special emphasis for those showing optical applications.

16.
PLoS Biol ; 14(2): e1002382, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26894589

RESUMO

Branching morphogenesis of the epithelial ureteric bud forms the renal collecting duct system and is critical for normal nephron number, while low nephron number is implicated in hypertension and renal disease. Ureteric bud growth and branching requires GDNF signaling from the surrounding mesenchyme to cells at the ureteric bud tips, via the Ret receptor tyrosine kinase and coreceptor Gfrα1; Ret signaling up-regulates transcription factors Etv4 and Etv5, which are also critical for branching. Despite extensive knowledge of the genetic control of these events, it is not understood, at the cellular level, how renal branching morphogenesis is achieved or how Ret signaling influences epithelial cell behaviors to promote this process. Analysis of chimeric embryos previously suggested a role for Ret signaling in promoting cell rearrangements in the nephric duct, but this method was unsuited to study individual cell behaviors during ureteric bud branching. Here, we use Mosaic Analysis with Double Markers (MADM), combined with organ culture and time-lapse imaging, to trace the movements and divisions of individual ureteric bud tip cells. We first examine wild-type clones and then Ret or Etv4 mutant/wild-type clones in which the mutant and wild-type sister cells are differentially and heritably marked by green and red fluorescent proteins. We find that, in normal kidneys, most individual tip cells behave as self-renewing progenitors, some of whose progeny remain at the tips while others populate the growing UB trunks. In Ret or Etv4 MADM clones, the wild-type cells generated at a UB tip are much more likely to remain at, or move to, the new tips during branching and elongation, while their Ret-/- or Etv4-/- sister cells tend to lag behind and contribute only to the trunks. By tracking successive mitoses in a cell lineage, we find that Ret signaling has little effect on proliferation, in contrast to its effects on cell movement. Our results show that Ret/Etv4 signaling promotes directed cell movements in the ureteric bud tips, and suggest a model in which these cell movements mediate branching morphogenesis.


Assuntos
Rim/embriologia , Morfogênese , Proteínas Proto-Oncogênicas c-ets/fisiologia , Proteínas Proto-Oncogênicas c-ret/fisiologia , Células-Tronco/fisiologia , Animais , Movimento Celular , Feminino , Masculino , Camundongos , Técnicas de Cultura de Órgãos
17.
J Cardiovasc Nurs ; 31(2): E1-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25829137

RESUMO

BACKGROUND: Subjects with type 2 diabetes mellitus are considered to be at high risk for cardiovascular disease. The identification of carotid atherosclerosis is a validated surrogate marker of cardiovascular disease. Nurses are key professionals in the improvement and intensification of cardiovascular preventive strategies. AIMS: The aim is to study the presence of carotid atherosclerosis in a group of asymptomatic subjects with type 2 diabetes mellitus and no previous clinical cardiovascular disease. METHODS: A total of 187 patients with type 2 diabetes mellitus and 187 age- and sex-matched subjects without type 2 diabetes mellitus were studied in this cross-sectional, observational, cohort study. Standard operational procedures were applied by the nursing team regarding physical examination and carotid ultrasound assessment. Common, bulb, and internal carotid arteries were explored by measuring intima-media thickness and identifying atherosclerotic plaques. RESULTS: Carotid intima-media thickness (c-IMT) and carotid plaque prevalence were significantly greater in diabetic subjects than in the control group. Carotid plaques and c-IMT were more frequent in men than in women and increased with increasing age. In the multivariate analysis, age, gender, waist circumference, systolic blood pressure, and hypercholesterolemia were positively associated with c-IMT, whereas age, gender, and weight were positively associated with carotid plaque. CONCLUSION: The current nurse-led study shows that subjects with type 2 diabetes mellitus have a high prevalence of subclinical atherosclerosis that is associated with cardiovascular risk factors.


Assuntos
Aterosclerose/etiologia , Espessura Intima-Media Carotídea , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Idoso , Aterosclerose/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Estudos de Casos e Controles , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
18.
Nanoscale ; 7(28): 12000-9, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26108470

RESUMO

Luminescent metallo-surfactants based on highly emissive dinuclear Re(I) complexes have been synthesized combining the peculiar photophysical behaviour of this class of neutral hydrophobic complexes with new properties imparted by hydrophilic chains anchored on the coordinated chromophoric ligand. In solution, the resulting neutral amphiphiles tend to self-assembly in soft structures. The aggregation properties have been thoroughly investigated in dioxane-water mixtures, where all the complexes assembly in globular-like supramolecular architectures with well-defined size (hydrodynamic diameter = 200-400 nm). The morphology of these nano-objects has been completely characterized with Dynamic Light Scattering (DLS) analysis, Scanning Transmission Electron Microscopy (STEM) and cryo-TEM to determine the size, polydispersity, and stability of the nanoparticles in relationship with the structure of the metallo-surfactants. The photophysical properties of both the isolated metal complexes and their aggregates have been investigated by means of UV-Vis absorption, steady-state and time-resolved emission spectroscopy. Noteworthy, the self-assembly properties of the reported luminescent rhenium metallo-amphiphiles can be modulated by solvent polarity. Even more importantly, such aggregation process yielded a small hypsochromic shift of the emission energy accompanied by a sizeable elongation of the excited-state lifetime and an enhancement of the photoluminescence quantum yield, reaching a remarkably high value of 0.20 despite the air-equilibrated aqueous condition. The presented findings endorse novel possibilities for the efficient use of soft-nanostructures based on metallo-amphiphiles in dual (electron and optical microscopy) bio-imaging applications and theranostics where the non-covalent nature of the intermolecular interactions would offer the powerful and unique possibility to reversibly assemble and disassemble imaging agents.


Assuntos
Luminescência , Nanopartículas/química , Rênio/química , Tensoativos/química , Nanopartículas/ultraestrutura , Tamanho da Partícula
19.
Chemistry ; 21(4): 1795-802, 2015 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-25413614

RESUMO

The synthesis of a series of 4-aryl-3,5-bis(arylethynyl)aryl-4H-1,2,4-triazoles derivatives is reported and the influence exerted by peripheral substitution on the morphology of the aggregates generated from these 1,2,4-triazoles is investigated by SEM imaging. The presence of paraffinic side chains results in long fibrillar supramolecular structures, but unsubstituted triazoles self-assemble into thinner ribbons and needle-like aggregates. The crystals obtained from methoxy-substituted triazoles have been utilised to elaborate a model that helps to justify aggregation of the investigated 1,2,4-triazoles, in which the operation of arrays of C-H⋅⋅⋅π non-covalent interactions plays a significant role. The results presented herein demonstrate the ability of simple molecules to behave as multitasking scaffolds with different properties, depending on peripheral substitution. Thus, although 1,2,4-triazoles without long paraffinic side chains exhibit optical waveguiding behaviour, triazoles endowed with peripheral paraffinic side chains exhibit hexagonal columnar mesomorphism.

20.
Angew Chem Int Ed Engl ; 53(48): 13121-5, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25346403

RESUMO

A single organism comprises diverse types of cells. To acquire a detailed understanding of the biological functions of each cell, comprehensive control and analysis of homeostatic processes at the single-cell level are required. In this study, we develop a new type of light-driven nanomodulator comprising dye-functionalized carbon nanohorns (CNHs) that generate heat and reactive oxygen species under biologically transparent near-infrared (NIR) laser irradiation. By exploiting the physicochemical properties of the nanohorns, cellular calcium ion flux and membrane currents were successfully controlled at the single-cell level. In addition, the nanomodulator allows a remote bioexcitation of tissues during NIR laser exposure making this system a powerful tool for single-cell analyses and innovative cell therapies.


Assuntos
Lasers , Nanoestruturas/uso terapêutico , Nanotecnologia/métodos , Animais , Anuros , Processos Fotoquímicos , Transdução de Sinais
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