Human movement and environmental barriers shape the emergence of dengue.

Understanding how emerging infectious diseases spread within and between countries is essential to contain future pandemics. Spread to new areas requires connectivity between one or more sources and a suitable local environment, but how these two factors interact at different stages of disease emergence remains largely unknown. Further, no analytical framework exists to examine their roles. Here we develop a dynamic modelling approach for infectious diseases that explicitly models both connectivity via human movement and environmental suitability interactions. We apply it to better understand recently observed (1995-2019) patterns as well as predict past unobserved (1983-2000) and future (2020-2039) spread of dengue in Mexico and Brazil. We find that these models can accurately reconstruct long-term spread pathways, determine historical origins, and identify specific routes of invasion. We find early dengue invasion is more heavily influenced by environmental factors, resulting in patchy non-contiguous spread, while short and long-distance connectivity becomes more important in later stages. Our results have immediate practical applications for forecasting and containing the spread of dengue and emergence of new serotypes. Given current and future trends in human mobility, climate, and zoonotic spillover, understanding the interplay between connectivity and environmental suitability will be increasingly necessary to contain emerging and re-emerging pathogens.

Comparing the copper binding features of alpha and beta synucleins.

Amyloid aggregation of α-synuclein (AS) is one of the hallmarks of Parkinson's disease (PD). Copper ions specifically bind at the N-terminus of AS, accelerating protein aggregation. Its protein homolog ß-synuclein (BS) is also a copper binding protein, but it inhibits AS aggregation. Here, a comparative spectroscopic study of the Cu2+ binding properties of AS and BS has been performed, using electronic absorption, circular dichroism (CD) and electronic paramagnetic resonance (EPR). Our comparative spectroscopic study reveals striking similarities between the Cu2+ binding features of the two proteins. The Cu2+ binding site at the N-terminal group of BS protein, modeled by the BS (1-15) fragment is identical to that of AS; however, its rate of reduction is three times faster as compared to the AS site, consistent with BS having an additional Met residue in its Met1-Xn-Met5-Xn-Met10 motif. The latter is also evident in the cyclic voltammetry studies of the Cu-BS complex. On the other hand, the Cu2+ binding features of the His site in both proteins, as modeled by AS(45-55) and BS(60-70), are identical, indicating that the shift in the His position does not affect its coordination features. Finally, replacement of Glu46 by Ala does not alter Cu2+ binding to the His site, suggesting that the familial PD E46K mutation would not impact copper-induced aggregation. While further studies of the redox activity of copper bound to His50 in AS are required to understand the role of this site in metal-mediated aggregation, our study contributes to a better understanding of the bioinorganic chemistry of PD.

Combined effects of hydrometeorological hazards and urbanisation on dengue risk in Brazil: a spatiotemporal modelling study.

BACKGROUND: Temperature and rainfall patterns are known to influence seasonal patterns of dengue transmission. However, the effect of severe drought and extremely wet conditions on the timing and intensity of dengue epidemics is poorly understood. In this study, we aimed to quantify the non-linear and delayed effects of extreme hydrometeorological hazards on dengue risk by level of urbanisation in Brazil using a spatiotemporal model. METHODS: We combined distributed lag non-linear models with a spatiotemporal Bayesian hierarchical model framework to determine the exposure-lag-response association between the relative risk (RR) of dengue and a drought severity index. We fit the model to monthly dengue case data for the 558 microregions of Brazil between January, 2001, and January, 2019, accounting for unobserved confounding factors, spatial autocorrelation, seasonality, and interannual variability. We assessed the variation in RR by level of urbanisation through an interaction between the drought severity index and urbanisation. We also assessed the effect of hydrometeorological hazards on dengue risk in areas with a high frequency of water supply shortages. FINDINGS: The dataset included 12 895 293 dengue cases reported between 2001 and 2019 in Brazil. Overall, the risk of dengue increased between 0-3 months after extremely wet conditions (maximum RR at 1 month lag 1·56 [95% CI 1·41-1·73]) and 3-5 months after drought conditions (maximum RR at 4 months lag 1·43 [1·22-1·67]). Including a linear interaction between the drought severity index and level of urbanisation improved the model fit and showed the risk of dengue was higher in more rural areas than highly urbanised areas during extremely wet conditions (maximum RR 1·77 [1·32-2·37] at 0 months lag vs maximum RR 1·58 [1·39-1·81] at 2 months lag), but higher in highly urbanised areas than rural areas after extreme drought (maximum RR 1·60 [1·33-1·92] vs 1·15 [1·08-1·22], both at 4 months lag). We also found the dengue risk following extreme drought was higher in areas that had a higher frequency of water supply shortages. INTERPRETATION: Wet conditions and extreme drought can increase the risk of dengue with different delays. The risk associated with extremely wet conditions was higher in more rural areas and the risk associated with extreme drought was exacerbated in highly urbanised areas, which have water shortages and intermittent water supply during droughts. These findings have implications for targeting mosquito control activities in poorly serviced urban areas, not only during the wet and warm season, but also during drought periods. FUNDING: Royal Society, Medical Research Council, Wellcome Trust, National Institutes of Health, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, and Conselho Nacional de Desenvolvimento Científico e Tecnológico. TRANSLATION: For the Portuguese translation of the abstract see Supplementary Materials section.

Electrografting of Carbon Surfaces with Aliphatic Chains and its Effect on the Rectification of Ferrocene as Redox Probe in Solution.

The mediated oxidation of acetate and octanoate ions in acetonitrile was used to covalently modify carbon surfaces with films bearing saturated aliphatic chains of different length. Film thickness increases proportionally with the length of the aliphatic chain within the carboxylate precursor. The thickest film was obtained from octanoate oxidation and rectification occurs when ferrocene is used as redox probe in acetonitrile solution. This effect increases with the bulky and hydrophobic nature of the supporting electrolyte cations; n-Hx4 N+ >n-Bu4 N+ >Me4 N+ . The combination of the bulky and hydrophobic properties of the supporting electrolyte ions as well as the hydrophobic properties of the electrografted films is the basis of rectification of ferrocene in cyclic voltammetry experiments. This phenomenon was simulated through a CEC mechanism in solution, where the mass transport inside the film channels was emulated through single chemical equilibria.

Experimental data on synthesis and characterization of chiral dinuclear manganese (II-II) compounds as biomimetic models of the active center of catalase.

Dinuclear manganese (II- III) compounds, which are potential models of the active center of catalase, were synthetized. This type of metalloenzymes presents biological importance due to three factors: they are redox catalyst centres, they are able to carry out hydrolytic reactions and they participate in activated processes via Lewis acids. Structurally, their active centre is composed by dinuclear manganese compounds, linked to nitrogen and oxygen donor atoms. An octahedral geometry around the metal ions were found, with acetate, hydroxy and aquo ligands; which can work as molecule bridges between them. The acid medium favours the electronic transfer between Mn3+ - Mn2+ as redox centre at 1.559 V and the consequent oxidation of hydrogen peroxide or organic molecules. The work also reports the data of two chiral novel compounds, [Mn2(S,S(+)Hcpse)4(NaClO4)2(NaOH)(CH4O)]n·[(C2H6O)2]n·[(CH4O)2]n and its respective enantioisomer, in which µ-oxo being as bridge metal centre. The X-ray structural was obtained as well as the optical and magnetic properties using Circular Dichroism, Electronic Paramagnetic Resonance, Magnetic Susceptibility and X-ray photoelectron spectroscopy.

Role of N-terminal methionine residues in the redox activity of copper bound to alpha-synuclein.

Amyloid aggregation of α-synuclein (AS) is one of the hallmarks of Parkinson's disease. The interaction of copper ions with the N-terminal region of AS promotes its amyloid aggregation and metal-catalyzed oxidation has been proposed as a plausible mechanism. The AS(1-6) fragment represents the minimal sequence that models copper coordination to this intrinsically disordered protein. In this study, we evaluated the role of methionine residues Met1 and Met5 in Cu(II) coordination to the AS(1-6) fragment, and in the redox activity of the Cu-AS(1-6) complex. Spectroscopic and electronic structure calculations show that Met1 may play a role as an axial ligand in the Cu(II)-AS(1-6) complex, while Met5 does not participate in metal coordination. Cyclic voltammetry and reactivity studies demonstrate that Met residues play an important role in the reduction and reoxidation processes of this complex. However, Met1 plays a more important role than Met5, as substitution of Met1 by Ile decreases the reduction potential of the Cu-AS(1-6) complex by ~80 mV, causing a significant decrease in its rate of reduction. Reoxidation of the complex by oxygen results in oxidation of the Met residues to sulfoxide, being Met1 more susceptible to copper-catalyzed oxidation than Met5. The sulfoxide species can suffer elimination of methanesulfenic acid, rendering a peptide with no thioether moiety, which would impair the ability of AS to bind Cu(I) ions. Overall, our study underscores the important roles that Met1 plays in copper coordination and the reactivity of the Cu-AS complex.

Competition between Hydrogen Bonding and Proton Transfer during Specific Anion Recognition by Dihomooxacalix[4]arene Bidentate Ureas.

Competition between hydrogen bonding and proton transfer reactions was studied for systems composed of electrogenerated dianionic species from dinitrobenzene isomers and substituted dihomooxacalix[4]arene bidentate urea derivatives. To analyze this competition, a second-order ErCrCi mechanism was considered where the binding process is succeeded by proton transfer and the voltammetric responses depend on two dimensionless parameters: the first related to hydrogen bonding reactions, and the second one to proton transfer processes. Experimental results indicated that, upon an increase in the concentration of phenyl-substituted dihomooxacalix[4]arene bidentate urea, voltammetric responses evolve from diffusion-controlled waves (where the binding process is at chemical equilibrium) into irreversible kinetic responses associated with proton transfer. In particular, the 1,3-dinitrobenzene isomer showed a higher proton transfer rate constant (∼25 M(-1) s(-1)) compared to that of the 1,2-dinitrobenzene (∼5 M(-1) s(-1)), whereas the 1,4-dinitrobenzene did not show any proton transfer effect in the experimental conditions employed.

Análisis comparativo de la repetibilidad y reproductibilidad de dos métodos de medición de la dimensión vertical en rehabilitación oral: una revisión sistemática / Comparative analysis of the repeatability and reproducibility of two methods for measuring the vertical dimension in oral rehabilitation: a systematic review

El objetivo de este estudio establecer si el método de evaluación de la dimensión vertical mediante cefalometría y el convencional con rodillos de articulación, consiguen resultados sin diferencias estadísticamente significativas. Realización de una revisión sistemática conforme a la metodología PICO del Centro de Medicina Basada en la Evidencia de Oxford. Se formula una pregunta dirigida al objetivo fijado y se elabora una estrategia de búsqueda empleando MeSH key words específicos derivados de la pregunta en la base de datos PubMed hasta 2015 y libros de rehabilitación oral. Se consultan un total de 833 artículos por título, siendo 26 revisados a texto completo. Se analizan trabajos sobre distintos métodos de determinación de la dimensión vertical, haciendo especial hincapié en los basados en métodos cefalométricos. Finalmente 9 artículos cumplen los criterios de inclusión y se realiza una evaluación crítica del nivel de evidencia. No se ha encontrado suficiente evidencia científica que demuestre la repetibilidad de ambos métodos. Es necesario realizar estudios controlados y aleatorizados que comparen ambos métodos para determinar si son repetibles y reproducibles y obtienen resultados sin diferencias estadísticamente significativas.

The objective of this work was to establish if the method of evaluation of the vertical dimension by cephalometry and the common one with joint rollers, obtains results without statistically significant differences. We carried out a systematic review based on the PICO methodology of the Center for Evidence-Based Medicine for Oxford. A question aimed at the objective was made, and a search strategy was developed using specific MeSH key words derived from the question in the Pubmed database up to 2015 and oral rehabilitation books. A total of 833 items were consulted by tittle, and for 26 of these full text was reviewed. Works on different methods for determining the vertical dimension were studied, with special emphasis on those based on cephalometric methods. Finally 9 articles fulfilled the criteria for inclusion and a critical assessment of the evidence level was performed. We did not find sufficient scientific evidence to demonstrate the repeatability of these methods. It is necessary to realize randomized controlled trials comparing both methods to determine if they were statistically repeatable and reproducible.

Accuracy of resonance frequency analysis by third generation Osstell® / Precisión del análisis de frecuencia de resonancia mediante Osstell® de tercera generación

The Resonance Frequency Analysis by Osstell® is used in the assessment of primary and secondary implant stability. The aim of this study was to determine its accuracy as a method of testing, checking its repeatability and reproducibility. A pilot study was performed whereby implants were placed in a cow rib to compare several ISQ measurements with the same SmartPeg transducer (repeatability), or with different SmartPegs (reproducibility). Statistical analysis of the data showed a high correlation of the ISQ values obtained in both assays, which suggests that Osstell®analysis can provide high repeatability and reproducibility.

El análisis de frecuencia de resonancia (AFR) por Osstell® se utiliza en la evaluación de la estabilidad primaria y secundaria del implante. El objetivo del presente estudio fue establecer la precisión del AFR mediante Osstell©, como método de prueba empleado en la determinación de la estabilidad implantaria. Se realizó un estudio experimental in vitro, en el que se colocaron implantes en una costilla de vaca y compararon diferentes mediciones del coeficiente de estabilidad del implante (ISQ) obtenidas sobre estos implantes con un mismo transductor SmartPeg (repetibilidad) o con diferentes SmartPegs (reproductibilidad). El análisis estadístico de los datos mostró una elevada correlación de los ISQ obtenidos en ambos ensayos, lo cual sugiere una reproductibilidad y repetibilidad elevada del análisis mediante Osstell.

Influencia del Diseño Micro y Macroscópico de la Región Cervical del Implante en la Preservación de Hueso Marginal Perimplantario: Una Revisión Sistemática / Influence of the Micro and Macroscopic Implant Neck Design in the Preservation of Marginal Bone Level: A Systematic Review

El objetivo de esta revisión sistemática fue evaluar los distintos diseños en el cuello del implante (pulido o tratado, con o sin intercambio de plataforma, o con o sin microespiras) y su posible influencia en la pérdida del hueso marginal periimplantario. Se llevo a cabo una revisión sistemática siguiendo la metodología PICO del Centro de Medicina Basada en la Evidencia de la Universidad de Oxford. La pregunta dirigida a la consecución de los objetivos fue: ¿Es el diseño del cuello del implante un factor crítico en la conservación del hueso marginal periimplantario? Se emplearon MeSH keywords específicos en las bases de datos Pubmed y Cochrane. Tres revisores independientes se pusieron de acuerdo en los estudios finalmente incluidos, obteniendo un índice de concordancia kappa de 0,88. De estos, se realizó una evaluación crítica del nivel de evidencia y también del riesgo de sesgo de los RCT mediante la Herramienta Cochrane. Se consultaron 445 artículos por título, incluyendo finalmente un total de 16 artículos a texto completo. La heterogeneidad de estos estudios impidió realizar un meta-análisis. No se encontró evidencia de que una determinada configuración del cuello del implante sea mejor que otra en la conservación del hueso marginal periimplantario y sin embargo, parece que una posición apico-coronal yuxtaósea del cuello pulido del implante respecto a la cresta ósea receptora pudiera ser crítica a ese respecto. No se encontró suficiente evidencia sobre la efectividad de las diferentes configuraciones de la región cervical del implante en la preservación del hueso marginal periimplantario. Son necesarios estudios clínicos controlados y aleatorizados a largo plazo para valorar los efectos de dichas modificaciones.

The aim of this systematic review was to assess whether different implant neck designs (polished or coated, with or without platform switching, either with or without microthreads) influence marginal bone resorption. A systematic review was conducted following the PICO methodology of the Centre for Evidence-Based Medicine of Oxford University. The question to the achievement of objectives was: Is the design of the implant neck a critical factor in the preservation of marginal bone levels? Specific MeSH keywords were used in the Pubmed and Cochrane databases. Three independent reviewers agreed on the studies ultimately included finding a concordance kappa index of 0.86. Of these articles, acritical evaluation of the level of evidence was performed and also the risk of bias of the RCT using the Cochrane tool. Four hundred forty-five items were reviewed by title, eventually including a total of 16 full-text articles. Heterogeneity of these studies made impossible the performance of a meta-analysis. No evidence that a particular configuration of the implant neck was better than another in preserving the peri-implant marginal bone was found, and yet it seems that an apico-coronal position juxta-osseous of the smooth neck of the implant relative to the bone crest could be decisive. Not enough evidence was found on the effectiveness of different configurations of the cervical region of the implant in the periimplant marginal bone preservation. More randomized controlled trials are needed to assess long-term effects of such modifications.

Redox cycling of copper-amyloid ß 1-16 peptide complexes is highly dependent on the coordination mode.

Copper (Cu)-amyloid ß (Aß) interactions play a role in the etiology of Alzheimer's disease. This work presents a spectroscopic and electrochemical study of two physiologically relevant Aß-Cu(II) complexes, as a function of pH and relative Cu-Aß(1-16) concentrations. Our results reveal that these coordination modes display distinct redox behaviors and provide experimental evidence for the existence of an intermediate Cu(I) species. A mechanism for the redox cycling of these complexes is proposed, providing further insight into the redox relevance of Aß-Cu interactions.

Self-decarboxylation of trichloroacetic acid redox catalyzed by trichloroacetate ions in acetonitrile solutions.

In mixtures of trichloroacetate ion and trichloroacetic acid in acetonitrile, trichloromethyl radicals are produced as a result of the redox reaction between the acid and its conjugate base. The reaction follows a loop mechanism in which the trichloroacetic acid is slowly consumed by proton reduction while the trichloroacetate ion is oxidized like in an electrochemical Kolbe reaction. The hydroquinone-trichloroacetate complex was a good sensor of this unexpected self-decarboxylation redox reaction.

Tacticity influence on the electrochemical reactivity of group transfer polymerization-synthesized PTMA.

Spectroscopic, thermal, and electrochemical characterization results are presented for the redox active polymer poly(2,2,6,6-tetramethyl-1-piperinidyloxy-4-yl methacrylate) or PTMA, synthesized by group transfer polymerization (GTP), and its precursors 4-hydroxy-tetramethylpiperidine-N-oxyl (HO-TEMPO) and 4-methacryloyloxy-tetramethylpiperidine-N-oxyl (MO-TEMPO). DSC analysis of synthesized PTMA showed that the glass transition temperature (T(g)) of the polymer structure occurs at 155 °C, corroborated by dynamic mechanical analysis (DMA), which is higher when compared with T(g) data for PTMA synthesized by other methods. Also, the amount of radical species present in PTMA synthesized by GTP reactions (100%) is higher than the values typically upon synthesizing PTMA by radical polymerization. Electrochemical and spectroelectrochemical-electron spin resonance studies in acetonitrile revealed two redox events in the PTMA polymer, one of which is reversible, accounting for ca. 80% of the spins in the polymer and giving rise to the battery behavior. The other redox event is irreversible, accounting for the remaining ca. 20% of spins, which has not previously been reported. These two redox events are linked to a structural property associated with the tacticity of the polymer, where the reversible feature (responsible for cathode behavior) is the dominant species. This corresponds to a number of isotactic domains of the polymer (determined by high temperature (1)H NMR). The second feature accounts for the three-line impurity observed in the ESR, which has been reported previously but poorly explained, associated to the number of heterotactic/syndiotactic triads.

Climate variability and dengue fever in warm and humid Mexico.

Multiple linear regression models were fitted to look for associations between changes in the incidence rate of dengue fever and climate variability in the warm and humid region of Mexico. Data were collected for 12 Mexican provinces over a 23-year period (January 1985 to December 2007). Our results show that the incidence rate or risk of infection is higher during El Niño events and in the warm and wet season. We provide evidence to show that dengue fever incidence was positively associated with the strength of El Niño and the minimum temperature, especially during the cool and dry season. Our study complements the understanding of dengue fever dynamics in the region and may be useful for the development of early warning systems.

Chemically controlled self-assembly of [2]pseudorotaxanes based on 1,2-bis(benzimidazolium)ethane cations and 24-crown-8 macrocycles.

Cations derived from 1,2-bis(benzimidazolium)ethane can penetrate the cavity of dibenzo-24-crown-8 macrocycles to produce a new family of [2]pseudorotaxanes. These supramolecular structures are held together by a series of charge-assisted hydrogen bonds (+)N-H[dot dot dot]O, ion-dipole and pi-stacking interactions. These new adducts were fully characterised by NMR spectroscopy, ESI mass spectrometry and single-crystal X-ray diffraction. The effect of electron-donating and electron-withdrawing groups on the association constants was also analyzed. Chemical control of the threading/unthreading process was acheived by the alternate addition of acid and base.