Electrochemical sensing at the fingertips: Wearable glove-based sensors for detection of 4-nitrophenol, picric acid and diazepam.

A wearable glove-based sensor is a portable and practical approach for onsite detection/monitoring of a variety of chemical threats. Herein, we report a flexible and sensitive wearable sensor fabricated on the nitrile glove fingertips by stencil-printing technique. The working electrodes were modified with multiwalled carbon nanotubes (MWCNTs)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) for sensitive and real-time analyses of hazardous or chemical treats, as picric acid (PA) explosive, diazepam (DZ) as drug-facilitated crimes and the emerging pollutant 4-nitrophenol (4-NP). The multi-sensing platform towards PA, 4-NP, and DZ offers the ability of in-situ qualitative and quantitative analyses of powder and liquid samples. A simple sampling by touching or swiping the fingertip sensor on the sample or surface under investigation using an ionic hydrogel combined with fast voltammetry measurement provides timely point-of-need analyses. The wearable glove-based sensor uses the square wave voltammetry (SWV) technique and exhibited excellent performance to detect PA, 4-NP, and DZ, resulting in limits of detection (LOD) of 0.24 µM, 0.35 µM, 0.06 µM, respectively, in a wide concentration range (from 0.5 µM to 100 µM). Also, we obtained excellent manufacturing reproducibility with relative standard deviations (RSD) in the range of 3.65%-4.61% using 7 different wearable devices (n = 7) and stability in the range of 4.86%-6.61% using different electrodes stored for 10 days at room temperature (n = 10), demonstrating the excellent sensor-to-sensor reproducibility and stability for reliable in-field measurements. The stretchable sensor presented great mechanical robustness, supporting up to 80 bending or stretching deformation cycles without significant voltammetric changes. Collectively, our wearable glove-based sensor may be employed for analyses of chemical contaminants of concern, such as explosives (PA), drugs (DZ), and emerging pollutants (4-NP), helping in environmental and public safety control.

Modification of Paper Surface by All-Lignin Coating Formulations.

All-lignin coating formulations were prepared while combining water-soluble cationic kraft lignin (quaternized LignoBoost®, CL) and anionic lignosulphonate (LS). The electrostatic attraction between positively charged CL and negatively charged LS led to the formation of insoluble self-organized macromolecule aggregates that align to films. The structures of the formed layers were evaluated by atomic force microscopy (AFM), firstly on glass lamina using dip-coating deposition and then on handsheets and industrial uncoated paper using roll-to-roll coating in a layer-by-layer mode. Coated samples were also characterized by optical microscopy, scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (SEM/EDS), and contact angle measurements. It was suggested that the structure of all-lignin aggregates is the result of the interaction of amphiphilic water-soluble lignin molecules leading to their specifically ordered mutual arrangement depending on the order and the mode of their application on the surface. The all-lignin coating of cellulosic fiber imparts lower air permeability and lower free surface energy to paper, mainly due to a decrease in surface polarity, thus promoting the paper's hydrophobic properties. Moderate loading of lignin coating formulations (5-6 g m-2) did not affect the mechanical strength of the paper.

Extensive characterization of choline chloride and its solid-liquid equilibrium with water.

The importance of choline chloride (ChCl) is recognized due to its widespread use in the formulation of deep eutectic solvents. The controlled addition of water in deep eutectic solvents has been proposed to overcome some of the major drawbacks of these solvents, namely their high hygroscopicities and viscosities. Recently, aqueous solutions of ChCl at specific mole ratios have been presented as a novel, low viscous deep eutectic solvent. Nevertheless, these proposals are suggested without any information about the solid-liquid phase diagram of this system or the deviations from the thermodynamic ideality of its precursors. This work contributes significantly to this matter as the phase behavior of pure ChCl and (ChCl + H2O) binary mixtures was investigated by calorimetric and analytical techniques. The thermal behavior and stability of ChCl were studied by polarized light optical microscopy and differential scanning calorimetry, confirming the existence of a solid-solid transition at 352.2 ± 0.6 K. Additionally, heat capacity measurements of pure ChCl (covering both ChCl solid phases) and aqueous solutions of ChCl (xChCl < 0.4) were performed using a heat-flow differential scanning microcalorimeter or a high-precision heat capacity drop calorimeter, allowing the estimation of a heat capacity change of (ChCl) ≈ 39.3 ± 10 J K-1 mol-1, between the hypothetical liquid and the observed crystalline phase at 298.15 K. The solid-liquid phase diagram of the ChCl + water mixture was investigated in the whole concentration range by differential scanning calorimetry and the analytical shake-flask method. The phase diagram obtained for the mixture shows an eutectic temperature of 204 K, at a mole fraction of choline chloride close to xChCl = 0.2, and a shift of the solid-solid transition of ChCl-water mixtures of 10 K below the value observed for pure choline chloride, suggesting the appearance of a new crystalline structure of ChCl in the presence of water, as confirmed by X-ray diffraction. The liquid phase presents significant negative deviations to ideality for water while COSMO-RS predicts a near ideal behaviour for ChCl.

Cationization of Eucalyptus Kraft LignoBoost Lignin: Preparation, Properties, and Potential Applications.

Current changes toward a more biobased economy have recently created tremendous renewed interest in using lignin as a valuable source for chemicals and materials. Here, we present a facile cationization approach aiming to impart kraft lignin water-solubility, with similar good features as lignosulfonates. Eucalyptus globulus kraft lignin obtained from a paper mill black liquor by applying the LignoBoost process was used as the substrate. Its reaction with 3-chloro-2-hydroxypropyl-trimethylammonium chloride (CHPTAC) in an aqueous alkaline medium was studied to assess the impact of different reaction conditions (temperature, time, educt concentration, molar CHPTAC-to-lignin ratio) on the degree of cationization. It has been shown that at pH 13, 10 wt % lignin content, 70 °C, and 3 h reaction time, a CHPTAC-to-lignin minimum molar ratio of 1.3 is required to obtain fully water-soluble products. Elemental analysis (4.2% N), size-exclusion chromatography (M w 2180 Da), and quantitative 13C NMR spectroscopy of the product obtained at this limit reactant concentration suggest introduction of 1.2 quaternary ammonium groups per C9 unit and substitution of 75% of the initially available phenolic OH groups. The possible contribution of benzylic hydroxyls to the introduction of quaternary ammonium moieties through a quinone methide mechanism has been proposed. Since both molecular characteristics and degree of substitution, and hence solubility or count of surface charge, of colloidal particles can be adjusted within a wide range, cationic kraft lignins are promising materials for a wide range of applications, as exemplarily demonstrated for flocculation of anionic dyes.

Assessing assemblage-wide mammal responses to different types of habitat modification in Amazonian forests.

Tropical forests are being heavily modified by varying intensities of land use ranging from structural degradation to complete conversion. While ecological responses of vertebrate assemblages to habitat modification are variable, such understanding is critical to appropriate conservation planning of anthropogenic landscapes. We assessed the responses of medium/large-bodied mammal assemblages to the ecological impacts of reduced impact logging, secondary regrowth, and eucalyptus and oil palm plantations in Eastern Brazilian Amazonia. We used within-landscape paired baseline-treatment comparisons to examine the impact of different types of habitat modification in relation to adjacent primary forest. We examined assemblage-wide metrics including the total number of species, number of primary forest species retained in modified habitats, abundance, species composition, and community integrity. We ranked all types of habitat modification along a gradient of assemblage-wide impact intensity, with oil palm and eucalyptus plantations exerting the greatest impact, followed by secondary regrowth, and selectively logging. Selectively-logged and secondary forests did not experience discernible biodiversity loss, except for the total number of primary forest species retained. Secondary forests further experienced pronounced species turnover, with loss of community integrity. Considering the biodiversity retention capacity of anthropogenic habitats, this study reinforces the landscape-scale importance of setting aside large preserved areas.

Difference Between the Profiles Presented by Yeasts that Colonize the Vaginal Mucosa or Cause Primary or Recurrent Candidiasis.

Candida yeasts are the most frequent in the vaginal content. This yeast may be a normal microbiota but also causes candidiasis. In symptomatic cases, primary candidiasis (VVC) or recurrence (RVVC) can be considered. This study aims to compare the frequency and in vitro sensitivity profile of Candida species isolated in the vaginal content with the different stages of the presence of yeasts. A total of 258 non-pregnant patients with/without VVC were prospectively screened at a teaching Health Centre of the Faculty of Medicine, in the University of Sao Paulo. The vaginal isolates were identified by traditional and molecular methods. Yeasts were isolated in 160 women. 34% were asymptomatic, 34% with vulvovaginal candidiasis (VVC), and 32% recurrent vulvovaginal candidiasis (RVVC). C. albicans was the most frequent species with 50.1% (82/160), followed by C. parapsilosis 13.7%(22/160), C. glabrata 12.5% (20/160), and C. tropicalis (6.2%). Analysis by the group showed that, in the asymptomatic group, eight yeast species were isolated, C. albicans 44.5% (24/54), C. glabrata 20% (11/54), C. parapsilosis and Rhodotorula rubra being the most frequent. In the VVC group, 11 yeast species were identified. Most isolates were C. albicans 68.5% (37/54), C. tropicalis 7.5% (4/54), and C. parapsilosis 5.5% (3/54). In the RVVC group, ten species were identified, the most frequent being C. albicans 38.5% (20/52), C. parapsilosis 17% (9/52), C. glabrata 4% (8/52), and C. tropicalis 6% (3/52). Less frequent species, such as C. haemulonii and Trichosporon spp, were isolated in the VVC and RVVC groups, C. kefyr was isolated in the three groups studied, and Rhodotorula spp was isolated in the control and RVVC groups. Candida metapsilosis was present in two isolates from the RVVC group. Most isolates were considered sensitive to the tested antifungals. Less sensitivity was seen for caspofungin. In this study, we were able to verify that the most common species of yeasts found in vaginal secretion were isolated in the three groups studied; however, there was the diversity of species in VVC and RVVC. Cryptic species C. haemulonii and were isolated in symptomatic patients. High levels of MICs, some of the antifungals tested, in the control group, draw attention in the group of asymptomatic women. We would like to emphasize that this research aims to assist clinicians and gynecologists, as well as assist in the epidemiological studies of candidiasis, in our country, how to draw attention to the profile of sensitivity/resistance to antifungals.

Antifungal sensitivity and species of yeasts in oral mucosa of street mixed-breed dogs.

The aim of this research is to verify the yeast species isolated from oral mucosa in street mixed-breed dogs and to determine the antifungal profiles. After capturing and sedating the animals, oral mucosa samples were collected from fifty dogs and the materials were inoculated on Sabouraud dextrose agar with chloramphenicol. Forty-three yeast strains were isolated and identified trough the API-20C AUX method. Thirty-seven (86.1%) of the yeasts belonged to genus Candida, five (11.6%) to genus Trichosporon and only one strain (2.3%) to genus Malassezia. The sensitivity profiles to anifungals (amphotericin B, itraconanole, ketoconazole, fluconazole and variconazole) were determined through Etest® method. This study found resistance of some yeasts to amphotericin B and a good susceptibility to voriconazole and ketoconazole. Some of these antifungals are used in veterinary medical practice. This research is the first investigation on street mixed-breed dogs regarding yeast identifications and antifungals profiles.

Hydroethanolic Extract of Solanum paniculatum L. Fruits Modulates ROS and Cytokine in Human Cell Lines.

Solanum paniculatum L. or popularly known as "jurubeba" is an herbal medicinal plant. A few studies have investigated its biological effects; however, research aimed at elucidating the redox balance effects from its fruits has not been reported so far. ROS interplays in various fields of medicine such as chemotherapy. Here, we evaluated antioxidant and inflammatory activities of the hydroethanolic extract of Solanum Paniculatum L. (HESPL) fruits in breast cancer cells, as well as its phytochemical profile. The antioxidant profile (carotenoids and phenolic compounds) was obtained by HPLC-DAD-UV and HPLC-APCI-MS. Cancer cell lines and human vein endothelial cells (HUVECs) were cultivated and treated with 1.87-30 µg/mL of HESPL for 24 hrs. Cytotoxicity, oxidative, and inflammation biomarkers were evaluated. The dose of 30 µg/mL of the HESPL extract presented cytotoxicity in the MCF-7 cell line. However, for MDA-MB-231, the cytotoxicity was observed in the dose of 1.87 g/mL. The 1.87 µg/mL and 3.75 µg/mL doses decreased the concentration of IL-6 in MCF-7 cells. In the MDA-MB-231 cells, the HESPL did not decrease the IL-6 concentration; however, in the doses of 15 and 30 µg/mL, an increase in this parameter was observed. The HESPL increased IL-1ß concentration in HUVECs. The ROS level in MCF-7 was elevated only at the 30 µg/ml dose. Regarding MDA-MB-231, HESPL promoted increased ROS levels at all doses tested. HUVEC showed no increase in ROS under any dose. HESPL treatment may modulate cytotoxicity, ROS, and cytokine levels due to its phytochemical profile, and it has shown an antioxidant or anti-inflammatory effect.

Yeasts and filamentous fungi in psittacidae and birds of prey droppings in midwest region of Brazil: a potential hazard to human health / Leveduras e fungos filamentosos em excretas de psittacideos e aves de rapina em cativeiro na região centro-oeste do Brasil: um risco potencial para a saúde humana

Abstract Birds of prey and from Psittacidae family are host to fungal microbiota and play an important role in the epidemiology of zoonoses. Few studies in the literature have characterized mycelial and yeast fungi in the droppings of these birds and correlated the isolates with the zoonotic potential of the microorganisms. Droppings from 149 birds were evaluated and divided into two groups: captive: Rhea americana araneipes, Primolius maracana, Ara ararauna, Ara chloropterus, Anodorhynchus hyacinthinus, Amazona aestiva, Ara macao macao, Ramphastos toco, Sarcoramphus papa, Busarellus nigricollis, Bubo virginianus nacurutu, Buteogallus coronatus, Buteogallus urubitinga urubitinga, Spizaetus melanoleucus, Spizaetus ornatus ornatus, Buteo albonotatus, Geranoaetus albicaudatus albicaudatus, Rupornis magnirostris magnirostris and Harpia harpyja, and quarantined birds: Amazona aestiva and Eupsitulla aurea. The fungal isolates were identified according to macroscopic (gross colony appearance), micromorphological and biochemical characteristics. Among birds displayed in enclosures, Aspergillus niger (41.1%) and Candida kefyr (63.8%) were the fungi most frequently isolated in Harpia harpyja and Ramphastos toco, respectively. For quarantined birds, the following percentages were observed in Eupsittula aurea , (76.6%) C. krusei, (84.4%) C. kefyr and (15.2%) C. famata, while in Amazona aestiva, (76.2%) C. krusei was observed. These findings indicate potentially pathogenic species in the bird droppings assessed, which constitute a risk of exposure for keepers and individuals who visit the zoo. Birds of the Cerrado and Pantanal of Mato Grosso (Central Western region of Brazil) could act in the epidemiological chain of important zoonoses.

Resumo Aves de rapina e psitacídeos são hospedeiras de uma rica microbiota fúngica e desempenham um papel importante na epidemiologia de zoonoses. Poucos estudos na literatura têm caracterizado fungos micelianos e leveduras nos excrementos de pássaros e correlacionados estes isolados com o potencial zoonótico dos microrganismos isolados. Excrementos de 149 aves foram divididas e avaliados em dois grupos: Em cativeiro: Rhea americana araneipes, Primolius maracana, Ara ararauna, Ara chloropterus, Anodorhynchus hyacinthinus, Amazona aestiva, Ara macao macao, Ramphastos toco, Sarcoramphus papa, Busarellus nigricollis , Bubo virginianus nacurutu, Buteogallus coronatus, Buteogallus urubutinga urubitinga, Spizaetus melanoleucus, Spizaetus ornatus ornatus, Buteo albonotatus, Geranoaetus albicaudatus albicaudatus, Rupornis magnirostris magnirostris e Harpia harpyja e aves em quarentena: Amazona aestiva e Eupsittula aurea). Os isolados de leveduras e de fungos micelianos foram identificados em observações macroscópicas (aspectos das colônias), características micromorfológicas e bioquímicas. Entre as aves indicadas em compartimentos, Aspergillus niger (41,1%) e Candida kefyr (63,8%) foram os fungos mais isolada em Harpia harpyja e Ramphastos toco, respectivamente. Para as aves em quarentena, os seguintes percentuais foram observados em Eupsittula aurea (76,6%) C. krusei, (84,4%) C. kefyr e (15,2%) C. famata, enquanto em Amazona aestiva (76,2%) de C. krusei foi observada. Estes resultados indicam a presença de espécies potencialmente patogênicos nas excretas das aves avaliadas, constituem um risco a exposição para os criadores e pessoas que visitam o zoológico. Aves do Pantanal e do Cerrado de Mato Grosso (região Centro-Oeste do Brasil) poderia atuar na cadeia epidemiológica das zoonoses importantes.

Prevalence of metabolic syndrome and associated factors in adults living in Fernando de Noronha, Brazil.

Metabolic Syndrome (MetS) is multivariate disease, clustered with socioeconomic and behavioral risk factors. Investigations about epidemiology estimative could be a prevention strategy. AIM: to investigate the prevalence of metabolic syndrome and its associated factors in adult population in Fernando de Noronha Archipelago (PE-Brazil). METHODS: A cross-sectional study was performed on a representative sample (N = 375) of adult residents of the region, aged 24-59 years, were harmonized according to the International Diabetes Federation (IDF) criteria. RESULTS: The prevalence of metabolic syndrome was 45 (12%) and, the age was associated with MetS, which increases the chances to MetS development around 3% respectively (OR: 1.03; CI 95%: 1.002-1.070 P 0.0384). Waist circumference was elevated in female population 266 (70.74%), however, levels of fasting blood glucose (304 [80.85%]), blood pressure (375 [100%]), TG (302 [80.32]), and low HDLc (297 [78.99]) presented normal biochemical values. There is no significative difference for male and female gender and, the social and behavior factors did not present significative association. CONCLUSION: The Fernando de Noronha presents lower prevalence of MetS thus, shows associations for elderly people. The waist circumference was elevated on female population. The results of this study provide further evidence and underscore the need for public health strategies that include education about MetS, promotion of cardiometabolic health, and prevention of undesirable outcomes such as diabetes and cardiovascular disease.

Yeasts and filamentous fungi in psittacidae and birds of prey droppings in midwest region of Brazil: a potential hazard to human health.

Birds of prey and from Psittacidae family are host to fungal microbiota and play an important role in the epidemiology of zoonoses. Few studies in the literature have characterized mycelial and yeast fungi in the droppings of these birds and correlated the isolates with the zoonotic potential of the microorganisms. Droppings from 149 birds were evaluated and divided into two groups: captive: Rhea americana araneipes, Primolius maracana, Ara ararauna, Ara chloropterus, Anodorhynchus hyacinthinus, Amazona aestiva, Ara macao macao, Ramphastos toco, Sarcoramphus papa, Busarellus nigricollis, Bubo virginianus nacurutu, Buteogallus coronatus, Buteogallus urubitinga urubitinga, Spizaetus melanoleucus, Spizaetus ornatus ornatus, Buteo albonotatus, Geranoaetus albicaudatus albicaudatus, Rupornis magnirostris magnirostris and Harpia harpyja, and quarantined birds: Amazona aestiva and Eupsitulla aurea. The fungal isolates were identified according to macroscopic (gross colony appearance), micromorphological and biochemical characteristics. Among birds displayed in enclosures, Aspergillus niger (41.1%) and Candida kefyr (63.8%) were the fungi most frequently isolated in Harpia harpyja and Ramphastos toco, respectively. For quarantined birds, the following percentages were observed in Eupsittula aurea , (76.6%) C. krusei, (84.4%) C. kefyr and (15.2%) C. famata, while in Amazona aestiva, (76.2%) C. krusei was observed. These findings indicate potentially pathogenic species in the bird droppings assessed, which constitute a risk of exposure for keepers and individuals who visit the zoo. Birds of the Cerrado and Pantanal of Mato Grosso (Central Western region of Brazil) could act in the epidemiological chain of important zoonoses.

Oral colonization: a possible source for candidemia in low-weight neonates.

OBJECTIVE: To check the oral colonization in neonates at high-risk and to associate these cases with candidemia. SUBJECTS AND METHODS: This study was conducted in the NICU. For six months, 125 high-risk neonates were investigated for oral colonization and septicemia by yeasts. From this total, 19 neonates had yeasts on the oral mucosae and 12 neonates developed fungemia. All of the 12 neonates with fungemia were included in the amount of 19 who have presented oral colonization by yeasts. RESULTS: There was a species concordance between the yeasts of the oral mucosae and the blood in 6 neonates (50%) among the 12 neonates with oral colonization and septicemia at the same time. The yeasts isolated in these 6 cases regarding the species concordance were Candida albicans (5 cases, 83.4%) and Candida parapsilosis (1 case, 16.6%). All of the cases involving an association were confirmed by PFGE. All of the strains of yeasts involved in oral colonization and also blood presented the same karyotype. A total of 66.6% of the patients with strains in agreement progressed to death. CONCLUSION: The results indicate the relevance of monitoring the oral microbiota, as a possible source of fungal infection, and assisting to develop appropriate therapeutic strategy.

Treatment with probiotics in experimental oral colonization by Candida albicans in murine model (DBA/2).

The aim of this study is to evaluate the oral colonization by Candida albicans in experimental murine immunosuppressed DBA/2 and treatment with probiotic bacteria. To achieve these objectives, 152 DBA/2-immunosuppressed mice were orally inoculated with a suspension of C. albicans containing 10(8) viable yeast cells, the animals were treated with nystatin or with the probiotics (Lactobacillus acidophilus and Lactobacillus rhamnosus). Evaluations were performed by Candida count from oral mucosa swabbing. The oral mucosa colonization by C. albicans started at day 1 after inoculation, remained maximal from day 3 until day 7, and then decreased significantly. Probiotics reduced the C. albicans colonization significantly on the oral mucosa in comparison with the untreated animal group. In the group treated with L. rhamnosus, the reduction in yeast colonization was significantly higher compared with that of the group receiving nystatin. Immunosuppressed animal model DBA/2 is a relevant model for experimental Candida oral colonization, and the treatment with probiotics in this model may be an effective alternative to prevent it.

Oral colonization by Candida species in AIDS pediatric patients.

The aim of this study was to assess the prevalence of factors associated with oral colonization by Candida spp. in pediatric patients with AIDS. The sample comprised of 117 children. Clinical status, medicines in use, and laboratory findings were obtained from hospital records; sociodemographic data were given by relatives. A dental examination assessed the prevalence of dental caries. The prevalence of oral colonization by Candida was 62%. Only seven children presented clinical manifestation of oral candidosis despite their high viral load index and low-for-age CD4 count. Candida colonization was directly associated with frequent use of antibiotics (prevalence ratio [PR] = 1.44), sulfa drugs (PR = 1.23), alteration in the oral mucosa (PR = 1.55), and untreated dental caries (PR = 1.93). It was inversely associated with the use of antiretroviral therapies (PR = 0.65). Candida albicans was the most frequently detected species (80%); phenotypic tests did not detect C. dubliniensis strains. This study observed a low prevalence of Candida-related oral lesions in these patients, which is compatible with the hypothesis that antiretroviral medicines may have contributed to reducing oral manifestations from Candida infection. The high prevalence of Candida colonization in HIV+/AIDS children with untreated dental caries reinforces the importance of oral health care in interdisciplinary health units that assist these patients.

Photoluminescent materials based on silica doped with lanthanide complexes of 4'-formylbenzo-15-crown-5.

Photoluminescent materials were prepared by introducing lanthanide complexes of 4'-formylbenzo-15-crown-5 (C15H20O6) into a silica matrix obtained by the sol-gel method. The new lanthanide complexes [Ln(C15H20O6)(NO3)3(H2O)2] (Ln3+ = Sm3+, Eu3+ and Tb3+) were synthesized and were fully characterised using spectroscopic techniques, and elemental and thermogravimetric analysis. Photoluminescence measurements were performed for the isolated Eu3+ and Tb3+ complexes as well as for their related silica based materials. A detailed comparative analysis on the photoluminescent properties of the EU3+ complex and of its derived silica material was carried out.

Photoluminescent lanthanide-organic bilayer networks with 2,3-pyrazinedicarboxylate and oxalate.

The hydrothermal reaction between lanthanide nitrates and 2,3-pyrazinedicarboxylic acid led to a new series of two-dimensional (2D) lanthanide-organic frameworks: [Ln(2)(2,3-pzdc)(2)(ox)(H(2)O)(2)](n) [where 2,3-pzdc(2-) = 2,3-pyrazinedicarboxylate, ox(2-) = oxalate, and Ln(III) = Ce, Nd, Sm, Eu, Gd, Tb, or Er]. The structural details of these materials were determined by single-crystal X-ray diffraction (for Ce(3+) and Nd(3+)) that revealed the formation of a layered structure. Cationic monolayers of {(infinity)(2)[Ln(2,3-pzdc)(H(2)O)](+)} are interconnected via the ox(2-) ligand leading to the formation of neutral (infinity)(2)[Ln(2)(2,3-pzdc)(2)(ox)(H(2)O)(2)] bilayer networks; structural cohesion of the crystalline packing is reinforced by the presence of highly directional O-H...O hydrogen bonds between adjacent bilayers. Under the employed hydrothermal conditions 2,3-pyrazinedicarboxylic acid can be decomposed into ox(2-) and 2-pyrazinecarboxylate (2-pzc(-)), as unequivocally proved by the isolation of the discrete complex [Tb(2)(2-pzc)(4)(ox)(H(2)O)(6)].10H(2)O. Single-crystal X-ray diffraction of this latter complex revealed its co-crystallization with an unprecedented (H(2)O)(16) water cluster. Photoluminescence measurements were performed for the Nd(3+), Sm(3+), Eu(3+), and Tb(3+) compounds which show, under UV excitation at room temperature, the Ln(3+) characteristic intra-4f(N) emission peaks. The energy level of the triplet states of 2,3-pyrazinedicarboxylic acid (18939 cm(-1)) and oxalic acid (24570 cm(-1)) was determined from the 12 K emission spectrum of the Gd(3+) compound. The (5)D(0) and (5)D(4) lifetime values (0.333 +/- 0.006 and 0.577 +/- 0.017 ms) and the absolute emission quantum yields (0.13 +/- 0.01 and 0.05 +/- 0.01) were determined for the Eu(3+) and Tb(3+) compounds, respectively. For the Eu(3+) compound the energy transfer efficiency arising from the ligands' excited states was estimated (0.93 +/- 0.01).

Prevalência de sobrepeso e obesidade em crianças de seis a dez anos de escolas municipais de área urbana / Prevalence of overweight and obesity in six to ten year-old students from urban county schools

OBJETIVO: Identificar a prevalência de sobrepeso e obesidade e fatores associados em alunos de seis a dez anos das escolas públicas municipais da área urbana de Marialva, no Paraná. MÉTODOS: Estudo transversal que utilizou uma amostra aleatória estratificada de 356 alunos. Foram avaliadas as seguintes variáveis: índice de massa corpórea, sexo, faixa etária, número de irmãos, atividade física e atividades sedentárias. Utilizou-se estatística descritiva para apresentação da distribuição da amostra nas estratificações. O teste do qui-quadrado foi aplicado para verificar a diferença entre a distribuição da amostra para cada uma das categorias das variáveis. A associação entre as variáveis foi realizada por meio da análise univariada, com razão de prevalência como medida de associação. RESULTADOS: A prevalência de sobrepeso encontrada foi de 20 por cento e a de obesidade de 7 por cento. A maioria dos alunos (72 por cento) não praticava atividade física fora da escola e pouco mais da metade deles (53 por cento) gastava mais de quatro horas por dia em atividades sedentárias. O número de irmãos foi a única variável associada com o excesso de peso (RP=1,64; IC95 por cento=1,10-2,45) para aqueles que tinham apenas um irmão e (RP=1,70; IC95 por cento=1,02-2,84) para os que não tinham irmão, quando comparados àqueles que tinham dois ou mais irmãos. CONCLUSÕES: Observou-se elevada prevalência de sobrepeso e obesidade nessa amostra, reforçando a necessidade de mais estudos em crianças residentes em municípios de pequeno porte, assim como de pesquisas e ações que visem prevenir e/ou tratar a obesidade.

OBJECTIVE: To identify the prevalence of overweight and obesity and associated factors among six to ten-year-old students from public county schools in the urban area of Marialva in Paraná, Brazil. METHODS: Cross-sectional study that used a stratified random sample of 356 students. The following variables were evaluated: body mass index, gender, age, number of siblings, physical activity and sedentary activities. Descriptive statistics was used to verify the distribution of the sample in the strata. The chi-square test was used in order to verify the differences between the distribution of the sample for each category of variables. The association between variables was tested by univariate analysis. RESULTS: Prevalence of overweight was 20 percent and obesity, 7 percent. Most students (72 percent) did not practice physical activity outside school and about half of them (53 percent) spent more than four hours a day in sedentary activities. The number of siblings was the only variable associated with excessive weight for those who had only one sibling (PR=1.64; 95 percentCI=1.10-2.45) and for those who had no siblings (PR=1.70; 95 percentCI=1.02-2.84), compared to those who had two or more siblings. CONCLUSIONS: There was a high prevalence of overweight and obesity in this sample. Further studies are needed in order to investigate the prevalence of this disease in children living in small Brazilian municipalities, as well as for research and actions to prevent and/or treat obesity.

Atividade hemolítica e produção de tubos germinativos relacionados ao potencial patogênico de isolados clínicos de Candida albicans / Hemolytic activity and production of germ tubes related to pathogenic potential of clinical isolates of Candida albicans

We assessed the virulence factor profile and in vitro antifungal susceptibility of 27 hospital isolates of C. albicans; 19 of these were from infections (16 urinary and three blood), and the other eight were isolated from sites of colonization (two from hands of health professionals, and six from central venous catheters). The virulence factors assayed were germ tube formation and production of extracellular products (hemolysins, proteinases, and phospholipases). Susceptibility to fluconazole, itraconazole, voriconazole and amphotericin B was determined by E-test. Regarding the virulence factors, the infection isolates produced significantly more hemolysin and germ tubes than the colonization isolates (p<0.05). There were no significant differences in the production of other factors between isolates from the two sources (p>0.05). Amphotericin B showed the lowest minimum inhibitory concentrations for all the isolates. The highest resistance was observed for the azoles, especially in the clinical isolates. These results suggest that the capacity of C. albicans to produce hemolysins and germ tubes may be associated with its pathogenic potential. Colonization isolates may pose a high risk of nosocomial infection, especially when the yeasts show resistance to antifungals.

O perfil de virulência e o de susceptibilidade in vitro aos antifúngicos de 27 amostras de C. albicans de origem hospitalar foi avaliado, sendo que 19 delas foram isoladas de infecções (16 urinárias e três sanguíneas) e as outras oito foram isoladas de colonização (duas de mãos de profissionais da saúde e seis de cateter venoso central). Os seguintes fatores de virulência foram investigados: formação de tubo germinativo e produção de compostos extracelulares (hemolisinas, proteinases e fosfolipases). Suscetibilidade ao fluconazol, itraconazol, voriconazol e anfotericina B foram determinadas por E-test. Em relação aos fatores de virulência, os isolados de infecção produziram significativamente mais hemolisina e tubos germinativos do que os de colonização (p<0.05). Não houve diferença significativa na produção das outras enzimas, entre os isolados das duas fontes (p>0.05). Anfotericina B mostrou as menores concentrações inibitórias mínimas para todos os isolados. Maiores índices de resistência foram observados aos azólicos, especialmente entre os isolados clínicos. Estes resultados sugerem que a capacidade de C. albicans produzir hemolisinas e tubos germinativos pode estar associada com seu potencial patogênico. Por outro lado, leveduras em colonização podem oferecer alto risco para infecção hospitalar, especialmente quando têm perfil de resistência aos antifúngicos.

Poly[[aqua-µ(3)-picolinato-µ(2)-picolinato-dipicolinatopotassium(I)terbium(III)] 2.5-hydrate].

In the title compound, [KTb(C(6)H(4)NO(2))(4)(H(2)O)]·2.5H(2)O, each Tb(3+) centre is coordinated by four N and five O atoms from five distinct picolinate ligands in a geometry resembling a highly distorted tricapped trigonal prism. One of the ligands establishes a skew bridge between neighbouring Tb(3+) centres, leading to the formation of one-dimensional anionic polymeric chains, {[(C(6)H(4)NO(2))(4)Tb](-)}(n), running along the direction [010]. Each K(+) cation is seven-coordinated by six O atoms from one anionic polymeric chain and one water mol-ecule [K⋯O 2.676 (3)-3.208 (4) Å]. The uncoordinated water mol-ecules are involved in O-H⋯O hydrogen bonding.

Photoluminescent, transparent and flexible di-ureasil hybrids containing CdSe/ZnS quantum dots.

We describe, in this paper, the sol-gel synthesis of di-ureasil based nanocomposites prepared in situ in the presence of organically capped CdSe quantum dots (QDs) or CdSe QDs which have been coated with a ZnS shell. For the latter a new chemical route to coat the CdSe QDs with ZnS shells was investigated and is now reported. The QDs became well dispersed in the final nanocomposites, whose microstructural homogeneity was evaluated by atomic force microscopy (AFM) and transmission electron microscopy (TEM) analyses. In order to understand the optical behaviour of di-ureasil containing QDs, a detailed photoluminescent study was undertaken for a selected particle size distribution of ZnS coated CdSe QDs (d∼4.5 nm). Emission quantum yields up to 0.11 were measured in the final nanocomposites that present a huge (between 3 and 6 orders of magnitude) increase in the lifetime of the QDs (relative to that of isolated ones), as a result of energy transfer occurring between the intimately mixed di-ureasil host and the QDs.