A Three-Dimensional Dynamic Supramolecular "Sticky Fingers" Organic Framework.

Engineering high-recognition host-guest materials is a burgeoning area in basic and applied research. The challenge of exploring novel porous materials with advanced functionalities prompted us to develop dynamic crystalline structures promoted by soft interactions. The first example of a pure molecular dynamic crystalline framework is demonstrated, which is held together by means of weak "sticky fingers" van der Waals interactions. The presented organic-fullerene-based material exhibits a non-porous dynamic crystalline structure capable of undergoing single-crystal-to-single-crystal reactions. Exposure to hydrazine vapors induces structural and chemical changes that manifest as toposelective hydrogenation of alternating rings on the surface of the [60]fullerene. Control experiments confirm that the same reaction does not occur when performed in solution. Easy-to-detect changes in the macroscopic properties of the sample suggest utility as molecular sensors or energy-storage materials

Presence of markers of activation pathways of macrophages in chronic periodontitis

Indexación: Web of Science; ScieloLa periodontitis crónica es una patología infecciosa, causada por un complejo de especies bacterianas, que afecta principalmente los tejidos de inserción de los dientes. La respuesta inmune-inflamatoria producida se caracteriza por la presencia de un infiltrado inflamatorio, en el cual los macrófagos representan entre 5 al 30%. Es sabido que los macrófagos se activan mediante dos vías: Clásica y Alterna, caracterizadas por la presencia de marcadores indirectos: IFN-γ e IL-6 para la vía clásica e IL-4 para la vía alterna, ampliamente abordados. Recientemente, se ha descrito a la subunidad A del factor XIII de la coagulación (FXIII-A) como un buen marcador de la vía alterna. El objetivo de este estudio consiste en determinar la presencia de IFN-γ, IL-6, FXIII-A e IL-4 como marcadores de las vías de activación de los macrófagos, en pacientes con periodontitis crónica. Para tal efecto, se realizó inmunohistoquímica y Western-Blot para los cuatro marcadores junto a CD-68, marcador de macrófagos, en 18 biopsias de tejido periodontal sano y 18 con periodontitis crónica. Se detectó la presencia de IFN-γ, IL-6, IL-4 y FXIII-A junto a CD68+, en todas las muestras de pacientes sanos y con periodontitis. Los resultados obtenidos sugieren que al estar presente IFN-γ, IL-6, IL-4 y FXIII-A, los macrófagos se activarían a través de ambas vías, lo cual, produciría una respuesta tanto proinflamatoria (Th1) como antinflamatoria (Th2). Son necesarios más estudios para determinar si existe una vía preferencial de activación.Periodontitis is a chronic infectious disease caused by a bacterial species complex, which affects mainly the insertion tissues of the teeth. The immune-inflammatory response produced is characterized by an inflammatory infiltrate in which macrophages represent between 5 to 30%. It is known and has been widely discussed that macrophages are activated in two ways: Classical and Alterna, characterized by the presence of indirect markers: IFN-γ and IL-6 for the classical pathway and IL-4 for the alternative pathway. Recently the subunit A of the clotting factor XIII (FXIII-A) has been described as a good marker of the alternative pathway. The objective of this study is to determine the presence of IFN-γ, IL-6, IL-4 and FXIII-A as markers of the macrophage activation pathways in patients with chronic periodontitis. To this end, we performed immunohistochemistry and Western blot for the four markers with CD68 macrophage marker, in 18 healthy periodontal tissue biopsies and 18 with chronic periodontitis. We detected the presence of IFN-γ, IL-6, IL-4 and FXIII-A with CD68 +, in all samples of healthy patients and periodontitis. The results suggest that when present, IFN-γ, IL-6, IL-4 and FXIII-A, activate macrophages through both routes, which would produce a proinflammatory response (Th1) as antiinflammatory (Th2). Further studies are necessary to determine whether there is a preferential pathway activation.http://www.scielo.cl/pdf/piro/v5n3/art06.pd

EOMYIDS FROM THE RIBESALBES-ALCORA BASIN (EARLY MIOCENE, IBERIAN PENINSULA) AND THEIR BIOSTRATIGRAPHIC AND PALAEOECOLOGICAL IMPLICATIONS.

Two species of the family Eomyidae are identified in the Early Miocene localities of the Araia d’Alcora outcrop (Ribesalbes-Alcora Basin, Iberian Peninsula): Ligerimys florancei and Ligerimys ellipticus. The first is rarer than the second, which is one of the most abundant mammals in the Ribesalbes-Alcora Basin assemblages. Due to its abundance, we are able to describe its variability in dental morphology, showing characteristics never previously observed, including the presence of a mesoloph or other features previously described only in ancient assemblages of this species, such as the presence of the anteroloph, which appears in younger assemblages in the Araia sequence. Furthermore, based on the eomyids, we divide the record of the Campisano Ravine section into two long local biozones, depending on the species present. In addition, each local biozone is divided into two smaller sub-biozones, depending on the abundance of each species. We retrospectively compare and correlate the assemblages studied here with other Ligerimys assemblages from the other basins in the Iberian Peninsula. We classify these sites based on the abundance and species of the genus Ligerimys. Additionally, we discuss the palaeoecological preferences of these specie

An orthogonal synthetic approach to nonsymmetrical bisazolyl 2,4,6-trisubstituted pyridines

A three-step synthetic route giving access to nonsymmetrical bisazolyl 2,4,6-trisubstituted pyridines with different substituents on the pyrazole, indazole, and pyridine heterocycles is described. From the readily available 4-bromo-2,6-difluoropyridine, both fluorine atoms allow for easy selective stepwise substitution, and the bromine atom provides easy access to additional functionalities through both Suzuki and Sonogashira Pd(0) cross-coupling reactions. These synthons represent optimal structures as building blocks in complexation and metalloorganic structures for the tuning of their chelating and photophysical propertie

Presencia de Linfocitos T Reguladores en Periodontitis Crónica

ResumenLa enfermedad periodontal requiere de un hospedero susceptible para su desarrollo y progresión. Dentro de las características del hospedero se encuentra la respuesta T reguladora, que otorga tolerancia frente a antígenos propios y participa durante las enfermedades infecciosas limitando el daño tisular, sin disminuir la respuesta antibacteriana. El presente estudio tiene por objetivo determinar la presencia, reclutamiento y función de Tregs en pacientes con periodontitis crónica. En 10 biopsias de tejido periodontal sano y con periodontits crónica se realizó inmunohistoquímica para marcadores (CD4, CD25, Foxp3), quimioquinas (CCL17, CCL22) y citoquinas (TGF-β, IL-10) de Tregs. Además de Western-Blot para detectar las citoquinas. Los resultados obtenidos sugieren una posible asociación entre células Tregs y la infección periodontal, ya que se confirma su reclutamiento y presencia. Sin embargo, son necesarios más estudios del posible desbalance con su contraparte pro-inflamatoria Th17, que expliquen en parte la compleja etiopatogenia de la enfermedad periodontal.AbstractPeriodontal disease requires a susceptible host to initiation, development and progression. T regulatory response is one of these inmunoregulatory characteristics of the susceptible host, which provide tolerance, tissular protection during infection without impairing the control of periodontopathogens. The aim of this study is to determinate the presence, homing and function of T regulatory cells (Tregs) in patients with chronic periodontitis. Ten biopsies were taken from pockets, the presence of Tregs markers (CD4, CD25, Foxp3), chemokines (CCL17, CCL22) and cytokines (TGF-β, IL-10) were determinate by immunohistochemistry. Cytokines also were detected with Western-Blot. Our results suggest a possible association between Tregs and periodontal infection, confirming homing and presence of Tregs. However, further studies are required to determine the possible imbalance with pro-inflammatory part Th17, that might explain the complex etiopathogenesis of periodontal disease

A Three-dimensional Dynamic Supramolecular “Sticky Fingers” Organic Framework

Engineering high recognition host-guest materials is a burgeoning area in basic and applied research. The challenge of exploring novel porous materials with advanced functionalities with the possibility of being largely scalable, prompted us to develop dynamic crystalline structures promoted by soft interactions. Herein, we demonstrate the first example of a pure molecular dynamic crystalline framework held together by means of weak van der Waals interactions. The presented organic fullerene-based material exhibits a non-porous dynamic crystalline structure capable of undergoing single-crystal to single-crystal reactions. Exposure to hydrazine vapors induce structural and chemical changes that evince the toposelective hydrogenation of alternating rings on the surface of the [60]fullerene. Control experiments confirm that the same reaction does not occur when performed in solution. This easily to detect change in the macroscopic properties paves the way for the real application of these materials

A three-dimensional dynamic supramolecular 'sticky fingers' organic framework

Engineering high-recognition host-guest materials is a burgeoning area in basic and applied research. The challenge of exploring novel porous materials with advanced functionalities prompted us to develop dynamic crystalline structures promoted by soft interactions. The first example of a pure molecular dynamic crystalline framework is demonstrated, which is held together by means of weak "sticky fingers" van der Waals interactions. The presented organic-fullerene-based material exhibits a non-porous dynamic crystalline structure capable of undergoing single-crystal-to-single-crystal reactions. Exposure to hydrazine vapors induces structural and chemical changes that manifest as toposelective hydrogenation of alternating rings on the surface of the [60]fullerene. Control experiments confirm that the same reaction does not occur when performed in solution. Easy-to-detect changes in the macroscopic properties of the sample suggest utility as molecular sensors or energy-storage material

Epidemiology of mid-buccal gingival recessions according to the 2018 Classification System in South America: Results from two population-based studies

AIM The aim of this investigation was to estimate the prevalence, severity and extent of mid-buccal gingival recessions (GRs; classified according to the 2018 Classification System) and to identify their risk indicators in the South American population. MATERIALS AND METHODS Epidemiological data from two cross-sectional studies-performed on 1070 South American adolescents and 1456 Chilean adults-were obtained. All participants received a full-mouth periodontal examination by calibrated examiners. GR prevalence was defined as the presence of at least one mid-buccal GR ≥ 1 mm. GRs were also categorized into different recession types (RTs) according to the 2018 World Workshop Classification System. Analyses for RT risk indicators were also performed. All analyses were carried out at the participant level. RESULTS The prevalence of mid-buccal GRs was 14.1% in South American adolescents and 90.9% in Chilean adults. In South American adolescents, the prevalence of RTs was 4.3% for RT1 GRs, 10.7% for RT2 GRs and 1.7% for RT3 GRs. In Chilean adults, the prevalence of RT1 GRs was 0.3%, while the prevalence of RT2 and RT3 GRs was 85.8% and 77.4%, respectively. Full-Mouth Bleeding Score (FMBS; <25%) was associated with the presence of RT1 GRs in adolescents. The risk indicators for RT2/RT3 GRs mainly overlapped with those for periodontitis. CONCLUSIONS Mid-buccal GRs affected 14.1% of South American adolescents, whereas they affected most of the Chilean adult population (>90%). While RT1 GRs are more commonly observed in a non-representative cohort of South American adolescents (when compared to Chilean adults), the majority of Chilean adults exhibit RT2/RT3 GRs

Expression of caspase-3, p53 and Bcl-2 in generalized aggressive periodontitis

BACKGROUND: Apoptosis, or programmed cell death is a form of physiological cell death. It is increased or decreased in the presence of infection, inflammation or tissue remodelling. Previous studies suggest that apoptosis is involved in the pathogenesis of inflammatory periodontal disease. The aim of the present study was to investigate the clinical features and known indicators of apoptosis (p53, Bcl-2, Caspase-3) in patients with generalized aggressive periodontitis (GAP) METHODS: Eight patients with GAP, who had sites with probing depths (PD) > 5 mm, and 10 periodontally-healthy persons were included in the study. Clinical examinations and PD were performed, and the plaque index and gingival index were recorded. Gingival tissues biopsies were obtained from active site of each patient and from healthy individuals. The expression of caspase-3, Bcl-2, and p53 was evaluated by immunohistochemistry RESULTS: There were no significant differences between GAP and control group with respect to levels of caspase-3 and p53 expression (P > 0.05). Contrary, the frequency of grade 3 expression of Bcl-2 was higher in GAP group than the control group. CONCLUSION: The higher frequency of Bcl-2 expression in GAP group indicates and delayed apoptosis can lead to increasing resident inflammatory cells in periodontal tissues and resulting in progressive periodontal destruction

Dental Caries Prevalence and Tooth Loss in Chilean Adult Population: First National Dental Examination Survey

The purpose of this study was to assess the prevalence of dental caries, tooth loss, and risk factors among adult population of Chile. Furthermore, age, gender, and behavioural specific differences in caries prevalence and tooth loss were examined. A national stratified multistage probabilistic sample design in two-age cohorts was applied to the Chilean population. A sample of 1553 adults, comprising 1088 individuals aged 35–44 and 465 senior individuals aged 65–74, were examined. The DMFT was evaluated following WHO recommendations using diagnostic criteria of caries lesions into dentin. The data were analyzed by univariate and multivariate models using logistic regression analyses. Results showed a mean DMFT of 15.06 in the 35–44-year-old group and of 21.57 in the 65–74 group. Factors related to tooth loss in the 35–44 group through univariate logistic regression were depression (OR 1.9 CI 95% 1.26–2.85), education level <12 years (OR 2.24 CI 95% 1.31–3.73), personal income (OR 1.51 CI 95% 1.04–2.19), and familiar income (OR 2.05 CI 95% 1.34–3.13), and through multivariate logistic regression in the same age group were depression (OR 1.93 CI 95% 1.24–3.0), education level <12 years (OR 1.94 CI 95% 1.2–3.14), and familiar income (OR 1.71 CI 95% 1.09–2.68). Factors related to tooth loss in the 65–74-year-old group through univariate logistic regression were education level <12 years (OR 2.54 CI 95% 1.3–4.96) and personal income (OR 1.66 CI 95% 1.05–2.63), and for multivariate logistic regression in the same age group, it was education level <12 years (OR 2.51 CI 95% 1.21–5.18). In conclusion, adult population in Chile showed a high prevalence of dental caries and tooth loss, as age, education level, personal and familiar incomes, and depression are being the main risk factors