Novel Discrete and Imprinted Fluoride-Selective Sensors: Bridging the Gap from DMSO to Aqueous Samples.

Fluoride in drinking water has beneficial or harmful health effects depending on its concentration. This highlights the need for new low-cost and portable sensors capable of in situ monitoring of F- ions. Unfortunately, achieving high levels of water compatibility and fluoride specificity remains a challenge. Here, four new urea-based discrete sensors are prepared and characterized. The sensors containing anthracenyl- (5) and 9H-fluorenyl- (7) signaling units exhibit intense luminescent emissions in dimethyl sulfoxide, the former being particularly sensitive and selective to fluoride. In water, 5 displays a superior sensitivity (871 M-1) and a detection limit (8 µm) below international guidelines, albeit with cross-sensitivity to H2PO4‾. To enhance the performance, 5 and 7 are embedded into a fluoride-imprinted polymeric matrix to give solid-state sensors (5P and 7P, respectively). 5P shows good sensitivity (360 M-1) and specificity in water. Besides, it has a low detection limit (35 µm) and a response linear range (118-6300 µm) encompassing the limit established by the Environmental Protection Agency (211 µm). Furthermore, 5P also displays good reusability and adequate recovery values in real-sample testing (102 ± 2%), constituting the first example of a low-cost anion-imprinted polymeric probe tailored for the selective sensing of fluoride in aqueous samples.

Urban green areas as earthworm species maintainers in Curitiba, Paraná, Brazil.

Urban green areas can have a high impact on soil fauna due the environmental changes caused by human activities. This work aimed to assess earthworm populations in urban sites in the city of Curitiba, Paraná, Brazil. Earthworms were sampled in two urban sites: the Campus Ecoville of the Universidade Positivo and the Casa Verde space and in two land use systems (Grass Lawn and Native Vegetation), in the summer of 2018 and 2019 and winter of 2019. A total of 1052 individuals were found, belonging to five families and 12 species were identified, of which five are native: Glossoscolex sp.55, Fimoscolex sp.36, Fimoscolex sp.37 (Glossoscolecidae), Andiorrhinus duseni (Rhinodrilidae) and Ocnerodrilidae sp.43 (Ocnerodrilidae) and seven are exotic species: Amynthas corticis, Amynthas morrisi, Metaphire californica, Metaphire schmardae (Megascolecidae), Dendrodrilus rubidus (Lumbricidae) and Pontoscolex corethrurus (Rhinodrilidae). Of the five native species found, four are new species and will be described in the future and the specie A. duseni belongs to the group known as giant earthworms (minhocuçu) with specimens larger than 30cm. Despite the predominance of exotic species (n=932) compared to native species (n=114), the presence of new species may indicate that the managed environments can preserve native species. Moreover, the difference in the total number (native vs. exotic) can be attributed to the ability of the exotic species to survive human disturbances.

[Primary ciliary dyskinesia in children. Role of electron microscopy in countries with medium economic resources]. / Discinesia ciliar primaria en niños. Rol de la microscopia electrónica en países de medianos recursos económicos.

Primary ciliary dyskinesia (PCD) is a rare genetic disease that produces functional and structural de fects in the cilia. In Peru, no cases of this disease have been reported in the pediatric population. OBJECTIVE: To describe the clinical, radiological and ciliary ultrastructure characteristics in children with PCD, in a country with medium economic resources. CLINICAL CASE: We report 5 patients with PCD treated at the Instituto Nacional de Salud del Niño-Breña (Peru). Age range 1 to 5 years (median 3 years). Three patients were male. The most frequent clinical manifestations were chronic wet cough, rhonchi, coarse crackles, recurrent bronchial obstructive syndrome, and recurrent pneumonia. All patients had atelectasis, three had bronchiectasis, and two had dextrocardia with situs inversus. Two patients had undergone lobectomy. Other causes of recurrent pneumonias were ruled out with im munodeficiency study, chlorine test and pulmonary aspiration The electron microscopy showed ab sence of the inner arm of dynein as the most frequent pattern. All patients received treatment with antibiotics, nebulization with hypertonic saline, and respiratory physiotherapy with good adherence. CONCLUSION: In medium incomes countries, electron microscopy associated with clinical and radio logical characteristics plays an important role in the early diagnosis of this disease. This is the first Peruvian report that contributes to the casuistry and epidemiology of this rare pathology.

Fe(III)-Complex-Imprinted Polymers for the Green Oxidative Degradation of the Methyl Orange Dye Pollutant.

One of the biggest problems worldwide is the pollution of natural water bodies by dyes coming from effluents used in the textile industry. In the quest for novel effluent treatment alternatives, the aim of this work was to immobilize Fe(III) complexes in molecularly imprinted polymers (MIPs) to produce efficient Fenton-like heterogeneous catalysts for the green oxidative degradation of the methyl orange (MO) dye pollutant. Different metal complexes bearing commercial and low-cost ligands were assayed and their catalytic activity levels towards the discoloration of MO by H2O2 were assessed. The best candidates were Fe(III)-BMPA (BMPA = di-(2-picolyl)amine) and Fe(III)-NTP (NTP = 3,3',3″-nitrilotripropionic acid), displaying above 70% MO degradation in 3 h. Fe(III)-BMPA caused the oxidative degradation through two first-order stages, related to the formation of BMPA-Fe-OOH and the generation of reactive oxygen species. Only the first of these stages was detected for Fe(III)-NTP. Both complexes were then employed to imprint catalytic cavities into MIPs. The polymers showed catalytic profiles that were highly dependent on the crosslinking agent employed, with N,N-methylenebisacrylamide (MBAA) being the crosslinker that rendered polymers with optimal oxidative performance (>95% conversion). The obtained ion-imprinted polymers constitute cheap and robust solid matrices, with the potential to be coupled to dye-containing effluent treatment systems with synchronous H2O2 injection.

Concordancia del volumen telediastólico final del ventrículo izquierdo medido por monitor ultrasónico y ecocardiografía / Concordance of the final telediastolic volume of the left ventricle measured by ultrasonic monitor and echocardiography / Concordância do volume telediastolólico final do ventrículo esquerdo medido por monitor ultra-sônico e ecocardiografia

Resumen: Antecedentes: La sepsis se ha asociado a alta mortalidad y disfunción cardiaca; la ecocardiografía es técnicamente difícil; el operador dependiente requiere personal capacitado y equipo disponible, por lo que la fórmula de Smith & Madigan (SMII), a través del monitor ultrasónico de gasto cardiaco, es un sustituto adecuado del inotropismo, pudiéndose inferir el volumen telediastólico final del ventrículo izquierdo (VDFVI) como un indicador de precarga. Métodos: En 56 pacientes diagnosticados con shock séptico, se midieron las siguientes fórmulas usando monitor ultrasónico de gasto cardiaco y comparándose con el volumen telediastólico final por ecocardiografía. SMII = (VS × (PAM - PVC + Gp))/(7.5 × SC × TF) VDFVI = VS × 2.7/SMII. Resultados: Comparamos los resultados medidos por ecocardiografía y fórmula de Smith & Madigan, usando el método de Bland & Altman, obtuvimos un R2=0.92, un coeficiente de Linn de 0.92 con LC95% más alto 32.45, LC95% inferior-39.45 y una tasa de error de 32%. Conclusión: La fórmula de Smith & Madigan podría ser útil para el cálculo de volumen telediastólico final del ventrículo izquierdo; aunque debemos determinar si esta medida es útil para tomar decisiones clínicas, ya que el porcentaje de error es mayor al 20%.

Abstract: Background: Sepsis has been associated with high mortality and cardiac dysfunction, echocardiography is technically difficult, depends on the operator, requires trained personnel and available equipment, so the Smith & Madigan formula (SMII) through the cardiac output monitor Ultrasonic is an adequate substitute of inotropism, being able to infer the final end-diastolic volume of the left ventricle (VDFVI) as indicator of preload. Methods: In 56 patients diagnosed with septic shock, the following formulas were measured by an ultrasonic cardiac output monitor and compared with final end-diastolic volume by echocardiography. SMII = (VS × (PAM-PVC + Gp))/(7.5 × SC × TF) VDFVI = VS × 2.7/SMII. Results: We compared the results measured by echocardiography and the Smith & Madigan formula, using the Bland & Altman method, we obtained an R2 = 0.92, a Linn coefficient of 0.92 with an LC95% higher 32.45, LC95% Lower - 39.45 and a 32% error rate. Conclusion: The Smith & Madigan formula could be useful for the calculation of final end-diastolic volume of the left ventricle. Although the percentage of error is greater than 20%, we must determine if this measure is useful for making clinical decisions.

Resumo: Contexto: A sepse tem sido associada com alta mortalidade e disfunção cardíaca. O ecocardiograma é tecnicamente difícil, operador dependente, requer pessoal treinado e equipamentos disponíveis de modo que a fórmula de Smith & Madigan (SMII) através do monitor ultra-sônico de débito cardíaco é um substituto adequado do inotropismo, sendo capaz de inferir o volume diastólico final do ventrículo esquerdo (VDFVI) como um indicador de pré-carga. Métodos: Foram mensuradas as seguintes fórmulas em 56 pacientes com diagnóstico de choque séptico, por meio de um monitor ultra-sônico do débito cardíaco e comparadas ao volume telediastólico ao final pelo ecocardiograma. SMII = (VS × (PAM-PVC + Gp))/(7.5 × SC × TF) VDFVI = VS X 2.7/SMII. Resultados: Comparou-se os resultados medidos pela ecocardiografia e a fórmula de Smith & Madigan utilizando o método de Bland & Altman, obtivemos um R2 = 0.92, um coeficiente de Linn de 0.92 com um LC95% maior 32.45, LC95% Inferior - 39.45 e uma Taxa de erro de 32%. Conclusão: A fórmula de Smith & Madigan poderia ser útil para o cálculo do volume telediastólico final do ventrículo esquerdo. Embora a porcentagem de erro seja maior que 20% devemos determinar se essa medida é útil para tomar decisões clínicas.

Comparación de la estimación de gasto cardiaco por ecocardiografía versus biorreactancia y monitor ultrasónico de gasto cardiaco / Comparison of cardiac output estimation by echocardiography, bioreactance and ultrasonic cardiac output monitor / Comparação da estimativa do debito cardíaco pela ecocardiografia versus biorreatância e monitor ultrassônico

Resumen: En terapia intensiva uno de los monitoreos más frecuentes fundamentales para la toma de decisiones clínicas en la reanimación del choque séptico es la estimación del gasto cardiaco. La ecocardiografía se ha posicionado como el estándar de oro en monitoreo no invasivo del gasto cardiaco; sin embargo, este tipo de monitoreo es operador dependiente y debe ser realizado por un experto. Otras técnicas, como la biorreactancia y USCOM, son 100% no invasivas, y estas mediciones no dependen del operador ni del experto. Objetivo: Analizar la concordancia del gasto cardiaco por ecocardiografía versus biorreactancia y USCOM. Material y métodos: Estudio observacional prospectivo en el que se midió en 26 pacientes diagnosticados con shock séptico ingresados en la Unidad de Cuidados el gasto cardiaco por ecocardiografía, biorreactancia y sistema USCOM. El método de Bland Altman se realizó para analizar el acuerdo entre las diferentes técnicas. También se calculó el coeficiente de Linn en los mismos grupos de mediciones. Resultados: La biorreactancia frente a la ecocardiografía informó un sesgo (media de las diferencias) de -0.08 con una desviación estándar (precisión) de 0.85 y un intervalo de confianza de 95% de 1.59 a -1.75, finalmente un error de 24% y un coeficiente de Linn de 0.78. USCOM versus ecocardiografía informó un sesgo (media de las diferencias) de 1.11 con una desviación estándar (precisión) de 0.95 y un intervalo de confianza de 95% de 2.98 a -0.75, finalmente un error de 41% y un coeficiente de Linn de 0.6. Conclusiones: La biorreactancia es un prometedor monitoreo continuo al parecer comparable a la ecocardiografía, por otro lado el monitoreo USCOM no es equiparable a ecocardiografía o biorreactancia. Se necesitan más estudios para comprobar esta observación.

Abstract: Cardiac output is the most frequent advanced monitoring in critical care units given its utility to guide resuscitation in septic shock. Echocardiography has been postulated has the gold standard for non-invasive cardiac output measurement, however this technique is operator-dependent and should be performed by an expert. Other techniques such as bioreactance and Doppler monitoring by semiautomatic USCOM system are 100% non-invasive techniques, also these measurements are not operator or expert dependent. Objective: To analyze the agreement of cardiac output by echocardiography vs Bioreactance and USCOM. Material and methods: Prospective observational study in which 26 patients diagnosed with septic shock admitted to the intensive care unit were cardiac output was measured by echocardiography, bioreactance and USCOM system. Bland Altman method was performed to analyze the agreement between the different techniques: echocardiography vs USCOM and echocardiography vs bioreactance. Also Linn coefficient was calculated in the same groups of measurements. Results: Bioreactance vs echocardiography reported a bias (mean of the differences) of -0.08 with a standard deviation (precision) of 0.85 and a 95% confidence interval of 1.59 to -1.75, finally an error of 24% and Linn coefficient of 0.78. USCOM vs echocardiography reported a bias (mean of the differences) of 1.11 with a standard deviation (precision) of 0.95 and a 95% confidence interval of 2.98 to -0.75, finally an error of 41% and Linn coefficient of 0.6. Conclusions: Bioreactance is a promising technique for cardiac output measurement given its good agreement with echocardiography, in the other hand USCOM did not showed a satisfactory agreement with echocardiography, more studies are needed to verify the clinical usefulness of these different techniques.

Resumo: Na unidade de terapia intensiva, um dos monitoramentos mais frequentes essenciais para a tomada de decisão clínica na ressuscitação do choque séptico é a estimativa do débito cardíaco. A ecocardiografia tem sido posicionada como o «padrão ouro¼ na monitorização não invasiva do débito cardíaco, no entanto esse tipo de monitoramento é dependente do operador e deve ser executado por um especialista. Outras técnicas como a biorreatância e o USCOM, são técnicas 100% não invasivas, e essas medidas não dependem do operador ou do especialista. Objetivo: Analisar a concordância do débito cardíaco pela ecocardiografia versus Biorreatância e USCOM. Material e métodos: Estudo observacional prospectivo em que 26 pacientes com diagnóstico de choque séptico admitidos na unidade de terapia intensiva, onde mediram-se o débito cardíaco por ecocardiografia, biorreatância e sistema USCOM. O método de Bland Altman foi utilizado para analisar a concordância entre as diferentes técnicas. O coeficiente de Linn também foi calculado nos mesmos grupos de medidas. Resultados: A biorreatância versus ecocardiografia relatou uma tendência (diferenças médias) de -0.08 com um desvio padrão (precisão) de 0.85 e um intervalo de confiança de 95% de 1.59 a -1.75, finalmente um erro de 24% e um coeficiente de Linn de 0.78. USCOM versus ecocardiografia relatou uma tendência (média de diferenças) de 1.11 com um desvio padrão (precisão) de 0.95 e um intervalo de confiança de 95% de 2.98 a -0.75, finalmente um erro de 41% e um coeficiente de Linn de 0.6. Conclusões: Biorreatância é um monitoramento contínuo promissor aparentemente comparável ao ecocardiograma; por outro lado, o monitoramento por USCOM não é comparável à ecocardiografia ou biorreactância. Mais estudos são necessários para verificar essa observação.

Solution Studies and Crystal Structures of Heteropolynuclear Potassium/Copper Complexes with Phytate and Aromatic Polyamines: Self-Assembly through Coordinative and Supramolecular Interactions.

Phytate (L12- ) is a relevant natural product. It interacts strongly with biologically relevant cations, due to the high negative charge exhibited in a wide pH range. The synthesis and crystal structures of the mixed-ligand Cu(II) polynuclear complexes K(H2 tptz)0.5 [Cu(H8 L)(tptz)] ⋅ 3.6H2 O (1), K(H2 O)3 {[Cu(H2 O)(bpca)]3 (H8 L)} ⋅ 1.75H2 O (2), and K1.5 (H2 O)2 [Cu(bpca)](H9.5 L) ⋅ 8H2 O (3) (tptz=2,4,6-tri(pyridin-2-yl)-1,3,5-triazine; Hbpca=bis(2-pyridylcarbonyl) amine) are reported herein. They were obtained by the use of an aromatic rigid amine, which satisfies some of the metal coordination sites and promotes the hierarchical assembly of 2D polymeric structures. Speciation of phytate-Cu(II)-Hbpca system and determination of complex stability constants were performed by means of potentiometric titrations, in 0.15 M NMe4 Cl at 37.0 °C, showing that, even in solution, this system is able to produce highly aggregated complexes, such as [Cu3 (bpca)3 (H7 L)]2- . Furthermore, the Cu(II)-mediated tptz hydrolysis was studied by UV-vis spectroscopy at room temperature in 0.15 M NMe4 Cl. Based on the equilibrium results and with the aid of molecular modelling tools, a plausible self-assembly process for 2 and 3 could be proposed.

Earthworm species in various land use systems in the Campos Gerais region of Lapa, Paraná, Brazil.

The Campos Gerais region of Paraná are on an ancient plateau of sandstone origin and are covered with a diverse vegetation including mainly grasslands and various types of Atlantic Forest (particularly Araucaria forest). The region represents an important natural capital for biodiversity conservation as well as for agricultural and forestry production. However, little is known of the species richness and diversity of soil macroinvertebrates in this region. In the present study we evaluated earthworm species occurrence and richness in five land use systems (LUS) in the southern part of the Campos Gerais in Lapa county. Earthworms were handsorted from up to 18 soil monoliths on five occasions over three years (Feb. 2014, Feb., Mar., Nov. 2015, Jul. 2016) in the following LUS: old native forest, native grassland, young regenerating forest and grass lawn in the Uru Reserve and annual crop fields (soybean) in neighboring private farms (not all systems were sampled on all occasions). Nine earthworm species belonging to four families and five genera were found, of which six were native and three exotic species (Dichogaster gracilis, Amynthas gracilis, A. corticis). Of the native species, Urobenus brasiliensis and Andiorrhinus duseni (a large bodied-worm) are already well known from S and SE Brazil, while the remaining four were new species that require further description (Fimoscolex n.sp.1 and n.sp.2, Glossoscolex n.sp.1 and n.sp.2). In general, more species were found in February (summer) than March and November. The cropping system (soybean) had the lowest abundance and species richness in relation to other sites, although in the young and old forests no earthworms were found on some sample dates. Given the several new species found in this small reserve, and the relatively few sites studied thus far in the Campos Gerais, further efforts are needed to adequately characterize the earthworm fauna of the region, from which many other species are expected.

Los niveles de acetilcolinesterasa en pacientes con inestabilidad hemodinámica descartan sepsis como causa de choque / The levels of acetylcholinesterase in patients with hemodynamic instability discard sepsis as a cause of shock / Níveis de acetilcolinesterase em pacientes com instabilidade hemodinâmica descartam sepse como causa de choque

Resumen: Introducción: La detección temprana de sepsis es fundamental para disminuir la mortalidad de este padecimiento. Hasta el momento, ninguna escala clínica ni biomarcador ha sido útil en su diagnóstico y detección precoz. Los niveles de actividad de la acetilcolinesterasa se han propuesto como un biomarcador muy prometedor para la detección de sepsis y choque séptico. Objetivo: Estudiar la utilidad de los niveles de acetilcolinesterasa en el diagnóstico de sepsis. Material y métodos: Estudio observacional y prospectivo, en pacientes de la Unidad de Cuidados Intensivos del Hospital San Ángel Inn Universidad con diagnóstico de inestabilidad hemodinámica, clasificados con presencia o no de sepsis, tomándose niveles de acetilcolinesterasa al ingreso. Resultados: Se evaluaron 44 pacientes, 27% con sepsis. Los valores de acetilcolinesterasa tuvieron validez diagnóstica para predecir sepsis (AUC: 0.852 IC 95%: 0.726-0.977, p < 0.001), con un punto de corte de 3,956 U/L, sensibilidad = 81%, especificidad = 75%. El valor de neutrófilos con corte < 74% también tuvo valor predictor de sepsis (AUC: 0,710 IC 95%: 0,512-0,907, p = 0.034) sensibilidad = 75%, especificidad = 75%. Conclusiones: En pacientes con inestabilidad hemodinámica con niveles de acetilcolinesterasa mayores de 4,000 U/L se descarta sepsis como causa de choque.

Abstract: Introduction: Early detection of sepsis is essential to reduce mortality from this condition. So far, no clinical scale or biomarker has been useful in its diagnosis and early detection. Levels of acetylcholinesterase activity have been proposed as a very promising biomarker for the detection of sepsis and septic shock. Objective: To study the usefulness of acetylcholinesterase levels in the diagnosis of sepsis. Material and methods: Observational and prospective study in patients of the Intensive Care Unit of the Hospital San Ángel Inn Universidad with diagnosis of hemodynamic instability, classified with or without sepsis, taking acetylcholinesterase levels at admission. Results: 44 patients were evaluated, 27% with sepsis. The acetylcholinesterase values ​​presented a normal distribution and had diagnostic validity to predict sepsis (AUC: 0.852 95% CI: 0.726-0.977, p < 0.001), with a cut-off value of < 3,956 U/L, sensitivity = 81%, specificity = 75%. The value of neutrophils with a cut < 74% also had a predictive value of sepsis (AUC: 0.710 95% CI: 0.512-0.907, p = 0.034) sensitivity = 75%, specificity = 75%. Conclusions: In patients with hemodynamic instability with acetylcholinesterase levels greater than 4,000 U/L, sepsis is ruled out as the cause of shock.

Resumo: Introdução: A detecção precoce da sepse é fundamental para reduzir a mortalidade desta doença. Até agora nenhuma escala clínica ou biomarcador tem sido útil em seu diagnóstico e detecção precoce. Os níveis de atividade da acetilcolinesterase têm sido propostos como um biomarcador muito promissor para a detecção de sepse e choque séptico. Objetivo: Estudar a utilidade dos níveis de acetilcolinesterase no diagnóstico da sepse. Material e métodos: Estudo observacional e prospectivo, realizado em pacientes da unidade de terapia intensiva do Hospital Universitário San Ángel Inn, com diagnóstico de instabilidade hemodinâmica, classificados com ou sem a presença de sepse, obtendo os níveis de acetilcolinesterase na admissão. Resultados: Foram avaliados 44 pacientes, 27% com sepse. Os valores de acetilcolinesterase apresentaram validade diagnóstica para predizer sepse (AUC: 0.852 IC 95%: 0.726-0.977, p < 0.001), com valor de corte 3956 U/L, sensibilidade = 81%, especificidade = 75%. O valor de neutrófilos com um corte < 74% também teve um valor preditivo de sepsis (AUC: 0.710 IC 95%: 0.512-0.907, p = 0.034) sensibilidade = 75%, especificidade = 75%. Conclusões: Em pacientes com instabilidade hemodinâmica com níveis de acetilcolinesterase superiores a 4,000 U/L a sepse é descartada como causa de choque.

Ibandronate metal complexes: solution behavior and antiparasitic activity.

To face the high costs of developing new drugs, researchers in both industry and academy are looking for ways to repurpose old drugs for new uses. In this sense, bisphosphonates that are clinically used for bone diseases have been studied as agents against Trypanosoma cruzi, causative parasite of Chagas disease. In this work, the development of first row transition metal complexes (M = Co2+, Mn2+, Ni2+) with the bisphosphonate ibandronate (iba, H4iba representing the neutral form) is presented. The in-solution behavior of the systems containing iba and the selected 3d metal ions was studied by potentiometry. Mononuclear complexes [M(Hxiba)](2-x)- (x = 0-3) and [M(Hiba)2]4- together with the formation of the neutral polynuclear species [M2iba] and [M3(Hiba)2] were detected for all studied systems. In the solid state, complexes of the formula [M3(Hiba)2(H2O)4]·6H2O were obtained and characterized. All obtained complexes, forming [M(Hiba)]- species under the conditions of the biological studies, were more active against the amastigote form of T. cruzi than the free iba, showing no toxicity in mammalian Vero cells. In addition, the same complexes were selective inhibitors of the parasitic farnesyl diphosphate synthase (FPPS) enzyme showing poor inhibition of the human one. However, the increase of the anti-T. cruzi activity upon coordination could not be explained neither through the inhibition of TcFPPS nor through the inhibition of TcSPPS (T. cruzi solanesyl-diphosphate synthase). The ability of the obtained metal complexes of catalyzing the generation of free radical species in the parasite could explain the observed anti-T. cruzi activity.

Self-Assembly of Manganese(II)-Phytate Coordination Polymers: Synthesis, Crystal Structure, and Physicochemical Properties.

myo-Inositol phosphates are an important group of biomolecules that are present in all eukaryotic cells. The most abundant member of this family in nature is InsP6 (phytate, L12- in its fully deprotonated form). Phytate interacts strongly with inorganic and organic cations, and this interaction is essential for determining the possible functions of this biomolecule. Herein, the chemical, thermodynamic, and structural characterization of phytate-MnII species is presented in a study aimed at understanding how the interaction of the two components modulates their biological roles and their bioavailability. Polynuclear complexes Mn5 (H2 L)⋅16 H2 O (1) and (H2 terpy)2 [Mn(H6 L)(terpy)(H2 O)]⋅17 H2 O (terpy=terpyridine) (2) were prepared and characterized by different techniques. The isolation of 1 and the determination of its solubility, together with potentiometric titrations of the MnII -phytate system, allow the full description of this binary system. The preparation and crystal structure of 2 show a novel coordination mode of phytate, that is, the formation of infinite polymeric chains through equatorial phosphate groups.

Mononuclear and polynuclear complexes ligated by an iminodiacetic acid derivative: synthesis, structure, solution studies and magnetic properties.

Two novel families of coordination polymers, [Ln(bzlida)(Hbzlida)]·H2O (Ln = La, Nd) and [Ln2(bzlida)3]·3H2O (Ln = Nd, Sm, Eu, Gd) were prepared by hydrothermal reaction of Ln2O3 with benzyliminodiacetic acid (H2bzlida). The conditions of synthesis, in particular the pH value, were selected on the basis of previous speciation studies reported in this work. The first type of complex consists of 1D chains built by a fully deprotonated ligand bridging two lanthanide ions and protonated Hbzlida(-) ligands connecting three cations. The second type is formed by [Ln2(bzlida)3] bimetallic units in which the ligand has a tridentate NOO coordination mode. This is expanded to a 2D network through carboxylate linkers. Under similar synthetic conditions but including copper acetate in the reaction mixture, a new compound was also obtained and characterized: [Cu(bzlida)2{Er(AcO)(H2O)5}2][Cu(bzlida)2]·6H2O (AcO = acetate). This salt is made up of the [Cu(bzlida)2{Er(AcO)(H2O)5}2](2+) heterotrimetallic complex cation containing an acetato bridge, and the [Cu(bzlida)2](2-) anion. The same reaction produces the monomeric [Cu(Hbzlida)2]·4H2O whose structure was also elucidated. Magnetic properties of the Gd(iii) derivative were studied and analyzed experimentally and theoretically. The results are compared and discussed with respect to those reported in the literature and a magnetostructural correlation is suggested.

Interaction of myo-inositol hexakisphosphate with biogenic and synthetic polyamines.

Within all the eukaryotic cells myo-inositol phosphates (InsPs) are an important group of biomolecules that are potentially related to signaling functions. The most abundant member of this family in nature is InsP6 (phytate, L(12-) in its fully deprotonated form). The complicated chemical behavior of this molecule demands a great effort to understand its function in the cell medium. In this work we follow our earlier studies on the interaction of InsP6 with metal cations by inclusion of polyamines (both biogenic and synthetic) as potential agents to produce stable adducts. The stability constants of InsP6-amine adducts and the relevant thermodynamic parameters ΔG°, ΔH°, and ΔS° were determined at 37.0 °C and 0.15 M ionic strength by means of potentiometric titrations and isothermal titration calorimetry (ITC). The biogenic amines studied were 1,4-diaminobutane (putrescine, put), 1,5-diaminopentane (cadaverine, cad), N-(3-aminopropyl)-1,4-diaminobutane (spermidine, spd), N,N'-bis(3-aminopropyl)-1,4-diaminobutane (spermine, spm), and 1-(4-aminobutyl)guanidine (agmatine, agm), while the synthetic models of longer polyamines were 1,19-dimethyl-1,4,7,10,13,16,19-heptaazanonadecane (Me2hexaen), 1,22-dimethyl-1,4,7,10,13,16,19,22-octaazadocosane (Me2heptaen), 1,25-dimethyl-1,4,7,10,13,16,19,22,25-nonaazapentacosane (Me2octaen) and N,N'-bis(3-aminopropyl)-1,3-propanediamine (3,3,3-tet). With the aid of molecular modeling, we also studied the structural aspects of molecular recognition in operation. The final result is a balance between many parameters including charge of the species, flexibility of the amines, H-bonds in the adduct, and desolvation processes.

The copper(II)-phytate-terpyridine ternary system: the first crystal structures showing the interaction of phytate with bivalent metal and ammonium cations.

Phytate, an abundant molecule in eukaryotic cells, interacts strongly with inorganic cations and polyamines. This interaction is essential for determining the possible functions of this biomolecule. We present here the first solution and crystallographic study of the formation of phytate complexes in the Cu(II)-phytate-terpy and phytate-terpy (terpy = 2,2':6',2''-terpyridine) systems.

Coordination, microprotonation equilibria and conformational changes of myo-inositol hexakisphosphate with pertinence to its biological function.

Within all the eukaryotic cells there is an important group of biomolecules that has been potentially related to signalling functions: the myo-inositol phosphates (InsPs). In nature, the most abundant member of this family is the so called InsP6 (phytate, L(12-)), for which our group has strived in the past to elucidate its intricate chemical behaviour. In this work we expand on our earlier findings, shedding light on the inframolecular details of its protonation and complexation processes. We evaluate systematically the chemical performance of InsP6 in the presence and absence of alkali and alkaline earth metal ions, through (31)P NMR measurements, in a non-interacting medium and over a wide pH range. The analysis of the titration curves by means of a model based on the cluster expansion method allows us to describe in detail the distribution of the different protonated microspecies of the ligand. With the aid of molecular modelling tools, we assess the energetic and geometrical characteristics of the protonation sequence and the conformational transition suffered by InsP6 as the pH changes. By completely characterizing the protonation pattern, conformation and geometry of the metal complexes, we unveil the chemical and structural basis behind the influence that the physiologically relevant cations, Na(+), K(+), Mg(2+) and Ca(2+) have over the phytate chemical reactivity. This information is essential in the process of gaining reliable structural knowledge about the most important InsP6 species in the in vitro and in vivo experiments, and how these features modulate their probable biological functions.

Inframolecular acid-base and coordination properties towards Na(+) and Mg(2+) of myo-inositol 1,3,4,5,6-pentakisphosphate: a structural approach to biologically relevant species.

The myo-inositol phosphates (InsPs) are specific signalling metabolites ubiquitous in eukaryotic cells. Although Ins(1,3,4,5,6)P(5) is the second most abundant member of the InsPs family, its certain biological roles are far from being elucidated, in part due to the large number of species formed by Ins(1,3,4,5,6)P(5) in the presence of metal ions. In light of this, we have strived in the past to make a complete and at the same time "biological-user-friendly" description of the Ins(1,3,4,5,6)P(5) chemistry with mono and multivalent cations. In this work we expand these studies focusing on the inframolecular aspects of its protonation equilibria and the microscopic details of its coordination behaviour towards biologically relevant metal ions. We present here a systematic study of the Ins(1,3,4,5,6)P(5) intrinsic acid-base processes, in a non-interacting medium, and over a wide pH range, analyzing the (31)P NMR curves by means of a model based on the Cluster Expansion Method. In addition, we have used a computational approach to analyse the energetic and structural features of the protonation and conformational changes of Ins(1,3,4,5,6)P(5), and how they are influenced by the presence of two physiologically relevant cations, Na(+) and Mg(2+).

Prevalência de complicações oftalmológicas em portadores de fraturas do complexo zigomático / Prevalence of ophthalmic complications in individuals with fractures of the zygomatic complex

OBJETIVO: Realizar estudo observacional e retrospectivo da prevalência de complicações oftalmológicas em indivíduos portadores de fratura de complexo zigomático. MATERIAL E MÉTODO: Foi realizada a análise retrospectiva por consulta a prontuários dos pacientes atendidos no ambulatório de Cirurgia Buco-Maxilo-Facial do Hospital Geral Roberto Santos, no período de janeiro de 2005 a junho de 2009. RESULTADOS: Este estudo mostrou uma maior incidência de fraturas no sexo masculino, sendo a amostra composta por 70 homens (92,2%) e 6 mulheres (7,8%) com idade média de 20 a 39 anos. Dentre as causas, destacaram-se os acidentes de trânsito, envolvendo, motocicleta, carros e bicicleta que foram os agentes etiológicos mais comuns em ambos os sexos, perfazendo um total de 41 casos (54,0%). As complicações oftalmológicas observadas podem ser classificadas em menores (transitórias) e maiores (que necessitam de tratamento adicional). CONCLUSÃO: Pacientes portadores de fraturas 67 do complexo zigomático apresentam incidência elevada de complicações oftalmológicas, o que justifica o atendimento multidisciplinar desses pacientes.

OBJECTIVES: To conduct an observational and retrospective study of the prevalence of ophthalmic complications in individuals with fractures of the zygomatic complex. MATERIAL AND METHODS: This retrospective analysis was carried out by consulting the records of the patients treated at the Oral and Maxillofacial Surgery Clinic of the Roberto Santos General Hospital from January 2005 to June 2009. RESULTS: The study, comprising 70 men (92.2%) and 6 women (7.8%) aged between 20 and 39 years, showed a higher incidence of fractures in males. Road accidents involving motorcycles, cars and bicycles were the most common etiological agent in both sexes, accounting for a total of 41 cases. The ophthalmic complications observed can be classified as minor (transitory) and major (requiring further treatment). CONCLUSIONS: Patients with fractures of the zygomatic complex present a high incidence of ophthalmic complications, which justifies their treatment in a multidisciplinary fashion.

The behaviour of inositol 1,3,4,5,6-pentakisphosphate in the presence of the major biological metal cations.

The inositol phosphates are ubiquitous metabolites in eukaryotes, of which the most abundant are inositol hexakisphosphate (InsP 6) and inositol 1,3,4,5,6-pentakisphosphate [Ins(1,3,4,5,6)P5)]. These two compounds, poorly understood functionally, have complicated complexation and solid formation behaviours with multivalent cations. For InsP 6, we have previously described this chemistry and its biological implications (Veiga et al. in J Inorg Biochem 100:1800, 2006; Torres et al. in J Inorg Biochem 99:828, 2005). We now cover similar ground for Ins(1,3,4,5,6)P5, describing its interactions in solution with Na+, K+, Mg2+, Ca2+, Cu2+, Fe2+ and Fe3+, and its solid-formation equilibria with Ca2+ and Mg2+. Ins(1,3,4,5,6)P5 forms soluble complexes of 1:1 stoichiometry with all multivalent cations studied. The affinity for Fe3+ is similar to that of InsP6 and inositol 1,2,3-trisphosphate, indicating that the 1,2,3-trisphosphate motif, which Ins(1,3,4,5,6)P5 lacks, is not absolutely necessary for high-affinity Fe3+ complexation by inositol phosphates, even if it is necessary for their prevention of the Fenton reaction. With excess Ca2+ and Mg2+, Ins(1,3,4,5,6)P5 also forms the polymetallic complexes [M4(H2L)] [where L is fully deprotonated Ins(1,3,4,5,6)P5]. However, unlike InsP6, Ins(1,3,4,5,6)P5 is predicted not to be fully associated with Mg2+ under simulated cytosolic/nuclear conditions. The neutral Mg2+ and Ca2+ complexes have significant windows of solubility, but they precipitate as [Mg4(H2L)] x 23H2O or [Ca4(H2L)] x 16H2O whenever they exceed 135 and 56 microM in concentration, respectively. Nonetheless, the low stability of the [M4(H2L)] complexes means that the 1:1 species contribute to the overall solubility of Ins(1,3,4,5,6)P 5 even under significant Mg2+ or Ca2+ excesses. We summarize the solubility behaviour of Ins(1,3,4,5,6)P5 in straightforward plots.

"Chelatable iron pool": inositol 1,2,3-trisphosphate fulfils the conditions required to be a safe cellular iron ligand.

Mammalian cells contain a pool of iron that is not strongly bound to proteins, which can be detected with fluorescent chelating probes. The cellular ligands of this biologically important "chelatable", "labile" or "transit" iron are not known. Proposed ligands are problematic, because they are saturated by magnesium under cellular conditions and/or because they are not "safe", i.e. they allow iron to catalyse hydroxyl radical formation. Among small cellular molecules, certain inositol phosphates (InsPs) excel at complexing Fe(3+) in such a "safe" manner in vitro. However, we previously calculated that the most abundant InsP, inositol hexakisphosphate, cannot interact with Fe(3+) in the presence of cellular concentrations of Mg(2+). In this work, we study the metal complexation behaviour of inositol 1,2,3-trisphosphate [Ins(1,2,3)P(3)], a cellular constituent of unknown function and the simplest InsP to display high-affinity, "safe", iron complexation. We report thermodynamic constants for the interaction of Ins(1,2,3)P(3) with Na(+), K(+), Mg(2+), Ca(2+), Cu(2+), Fe(2+) and Fe(3+). Our calculations indicate that Ins(1,2,3)P(3) can be expected to complex all available Fe(3+) in a quantitative, 1:1 reaction, both in cytosol/nucleus and in acidic compartments, in which an important labile iron subpool is thought to exist. In addition, we calculate that the fluorescent iron probe calcein would strip Fe(3+) from Ins(1,2,3)P(3) under cellular conditions, and hence labile iron detected using this probe may include iron bound to Ins(1,2,3)P(3). Therefore Ins(1,2,3)P(3) is the first viable proposal for a transit iron ligand.

The behaviour of myo-inositol hexakisphosphate in the presence of magnesium(II) and calcium(II): protein-free soluble InsP6 is limited to 49 microM under cytosolic/nuclear conditions.

Progress in the biology of myo-inositol hexakisphosphate (InsP(6)) has been delayed by the lack of a quantitative description of its multiple interactions with divalent cations. Our recent initial description of these [J. Torres, S. Dominguez, M.F. Cerda, G. Obal, A. Mederos, R.F. Irvine, A. Diaz, C. Kremer, J. Inorg. Biochem. 99 (2005) 828-840] predicted that under cytosolic/nuclear conditions, protein-free soluble InsP(6) occurs as Mg(5)(H(2)L), a neutral complex that exists thanks to a significant, but undefined, window of solubility displayed by solid Mg(5)(H(2)L).22H(2)O (L is fully deprotonated InsP(6)). Here we complete the description of the InsP(6)-Mg(2+)-Ca(2+) system, defining the solubilities of the Mg(2+) and Ca(2+) (Ca(5)(H(2)L).16H(2)O) solids in terms of K(s0)=[M(2+)](5)[H(2)L(10-)], with pK(s0)=32.93 for M=Mg and pK(s0)=39.3 for M=Ca. The concentration of soluble Mg(5)(H(2)L) at 37 degrees C and I=0.15M NaClO(4) is limited to 49muM, yet InsP(6) in mammalian cells may reach 100muM. Any cytosolic/nuclear InsP(6) in excess of 49muM must be protein- or membrane-bound, or as solid Mg(5)(H(2)L).22H(2)O, and any extracellular InsP(6) (e.g. in plasma) is surely protein-bound.