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1.
Nature ; 607(7918): 301-306, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35831604

RESUMO

Our understanding of the climatic teleconnections that drove ice-age cycles has been limited by a paucity of well-dated tropical records of glaciation that span several glacial-interglacial intervals. Glacial deposits offer discrete snapshots of glacier extent but cannot provide the continuous records required for detailed interhemispheric comparisons. By contrast, lakes located within glaciated catchments can provide continuous archives of upstream glacial activity, but few such records extend beyond the last glacial cycle. Here a piston core from Lake Junín in the uppermost Amazon basin provides the first, to our knowledge, continuous, independently dated archive of tropical glaciation spanning 700,000 years. We find that tropical glaciers tracked changes in global ice volume and followed a clear approximately 100,000-year periodicity. An enhancement in the extent of tropical Andean glaciers relative to global ice volume occurred between 200,000 and 400,000 years ago, during sustained intervals of regionally elevated hydrologic balance that modified the regular approximately 23,000-year pacing of monsoon-driven precipitation. Millennial-scale variations in the extent of tropical Andean glaciers during the last glacial cycle were driven by variations in regional monsoon strength that were linked to temperature perturbations in Greenland ice cores1; these interhemispheric connections may have existed during previous glacial cycles.

2.
Environ Res ; 231(Pt 3): 116280, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37257742

RESUMO

This work presents a one-step synthesis methodology for preparing a hydrochar (HC) doped with TiO2 (HC-TiO2) for its application on the degradation of crystal violet (CV) using UV and visible radiation. Byrsonima crassifolia stones were used as precursors along with TiO2 particles. The HC-TiO2 sample was synthesized at 210 °C for 9 h using autogenous pressure. The photocatalyst was characterized to evaluate the TiO2 dispersion, specific surface area, graphitization degree, and band-gap value. Finally, the degradation of CV was investigated by varying the operating conditions of the system, the reuse of the catalyst, and the degradation mechanism. The physicochemical characterization of the HC-TiO2 composite showed good dispersion of TiO2 in the carbonaceous particle. The presence of TiO2 on the hydrochar surface yields a bandgap value of 1.17 eV, enhancing photocatalyst activation with visible radiation. The degradation results evidenced a synergistic effect with both types of radiation due to the hybridized π electrons in the sp2-hybridized structures in the HC surface. The degradation percentages were on average 20% higher using UV radiation than visible radiation under the following conditions: [CV] = 20 mg/L, 1 g/L of photocatalyst load, and pH = 7.0. The reusability experiments demonstrated the feasibility of reusing the HC-TiO2 material up to 5 times with a similar photodegradation percentage. Finally, the results indicated that the HC-TiO2 composite could be considered an efficient material for the photocatalytic treatment of water contaminated with CV.


Assuntos
Violeta Genciana , Raios Ultravioleta , Luz , Titânio/química , Catálise
3.
Nutr Metab Cardiovasc Dis ; 33(11): 2179-2188, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37586924

RESUMO

BACKGROUND AND AIMS: Accomplishing a high day-to-day reproducibility is important to detect changes in resting metabolic rate (RMR) and respiratory exchange ratio (RER) that may be produced after an intervention or for monitoring patients' metabolism over time. We aimed to analyze: (i) the influence of different methods for selecting indirect calorimetry data on RMR and RER assessments; and, (ii) whether these methods influence RMR and RER day-to-day reproducibility. METHODS AND RESULTS: Twenty-eight young adults accomplished 4 consecutive RMR assessments (30-min each), using the Q-NRG (Cosmed, Rome, Italy), the Vyntus CPX (Jaeger-CareFusion, Höchberg, Germany), the Omnical (Maastricht Instruments, Maastricht, The Netherlands), and the Ultima CardiO2 (Medgraphics Corporation, St. Paul, Minnesota, USA) carts, on 2 consecutive mornings. Three types of methods were used: (i) short (periods of 5 consecutive minutes; 6-10, 11-15, 16-20, 21-25, and 26-30 min) and long time intervals (TI) methods (6-25 and 6-30 min); (ii) steady state (SSt methods); and, (iii) methods filtering the data by thresholding from the mean RMR (filtering methods). RMR and RER were similar when using different methods (except RMR for the Vyntus and RER for the Q-NRG). Conversely, using different methods impacted RMR (all P ≤ 0.037) and/or RER (P ≤ 0.009) day-to-day reproducibility in all carts. The 6-25 min and the 6-30 min long TI methods yielded more reproducible measurements for all metabolic carts. CONCLUSION: The 6-25 min and 6-30 min should be the preferred methods for selecting data, as they result in the highest day-to-day reproducibility of RMR and RER assessments.

4.
J Endocrinol Invest ; 46(3): 567-576, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36242744

RESUMO

OBJECTIVE: Human brown adipose tissue (BAT) has gained considerable attention as a potential therapeutic target for obesity and its related cardiometabolic diseases; however, whether the gut microbiota might be an efficient stimulus to activate BAT metabolism remains to be ascertained. We aimed to investigate the association of fecal microbiota composition with BAT volume and activity and mean radiodensity in young adults. METHODS: 82 young adults (58 women, 21.8 ± 2.2 years old) participated in this cross-sectional study. DNA was extracted from fecal samples and 16S rRNA sequencing was performed to analyse the fecal microbiota composition. BAT was determined via a static 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography scan (PET/CT) after a 2 h personalized cooling protocol. 18F-FDG uptake was also quantified in white adipose tissue (WAT) and skeletal muscles. RESULTS: The relative abundance of Akkermansia, Lachnospiraceae sp. and Ruminococcus genera was negatively correlated with BAT volume, BAT SUVmean and BAT SUVpeak (all rho ≤ - 0.232, P ≤ 0.027), whereas the relative abundance of Bifidobacterium genus was positively correlated with BAT SUVmean and BAT SUVpeak (all rho ≥ 0.262, P ≤ 0.012). On the other hand, the relative abundance of Sutterellaceae and Bifidobacteriaceae families was positively correlated with 18F-FDG uptake by WAT and skeletal muscles (all rho ≥ 0.213, P ≤ 0.042). All the analyses were adjusted for the PET/CT scan date as a proxy of seasonality. CONCLUSION: Our results suggest that fecal microbiota composition is involved in the regulation of BAT and glucose uptake by other tissues in young adults. Further studies are needed to confirm these findings. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov no. NCT02365129 (registered 18 February 2015).


Assuntos
Microbiota , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Feminino , Humanos , Adulto Jovem , Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Marrom/metabolismo , Estudos Transversais , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons , RNA Ribossômico 16S/genética
5.
Persoonia ; 48: 261-371, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38234686

RESUMO

Novel species of fungi described in this study include those from various countries as follows: Australia, Agaricus albofoetidus, Agaricus aureoelephanti and Agaricus parviumbrus on soil, Fusarium ramsdenii from stem cankers of Araucaria cunninghamii, Keissleriella sporoboli from stem of Sporobolus natalensis, Leptosphaerulina queenslandica and Pestalotiopsis chiaroscuro from leaves of Sporobolus natalensis, Serendipita petricolae as endophyte from roots of Eriochilus petricola, Stagonospora tauntonensis from stem of Sporobolus natalensis, Teratosphaeria carnegiei from leaves of Eucalyptus grandis × E. camaldulensis and Wongia ficherai from roots of Eragrostis curvula. Canada, Lulworthia fundyensis from intertidal wood and Newbrunswickomyces abietophilus (incl. Newbrunswickomyces gen. nov.) on buds of Abies balsamea. Czech Republic, Geosmithia funiculosa from a bark beetle gallery on Ulmus minor and Neoherpotrichiella juglandicola (incl. Neoherpotrichiella gen. nov.) from wood of Juglans regia. France, Aspergillus rouenensis and Neoacrodontium gallica (incl. Neoacrodontium gen. nov.) from bore dust of Xestobium rufovillosum feeding on Quercus wood, Endoradiciella communis (incl. Endoradiciella gen. nov.) endophytic in roots of Microthlaspi perfoliatum and Entoloma simulans on soil. India, Amanita konajensis on soil and Keithomyces indicus from soil. Israel, Microascus rothbergiorum from Stylophora pistillata. Italy, Calonarius ligusticus on soil. Netherlands, Appendopyricularia juncicola (incl. Appendopyricularia gen. nov.), Eriospora juncicola and Tetraploa juncicola on dead culms of Juncus effusus, Gonatophragmium physciae on Physcia caesia and Paracosmospora physciae (incl. Paracosmospora gen. nov.) on Physcia tenella, Myrmecridium phragmitigenum on dead culm of Phragmites australis, Neochalara lolae on stems of Pteridium aquilinum, Niesslia nieuwwulvenica on dead culm of undetermined Poaceae, Nothodevriesia narthecii (incl. Nothodevriesia gen. nov.) on dead leaves of Narthecium ossifragum and Parastenospora pini (incl. Parastenospora gen. nov.) on dead twigs of Pinus sylvestris. Norway, Verticillium bjoernoeyanum from sand grains attached to a piece of driftwood on a sandy beach. Portugal, Collybiopsis cimrmanii on the base of living Quercus ilex and amongst dead leaves of Laurus and herbs. South Africa, Paraproliferophorum hyphaenes (incl. Paraproliferophorum gen. nov.) on living leaves of Hyphaene sp. and Saccothecium widdringtoniae on twigs of Widdringtonia wallichii. Spain, Cortinarius dryosalor on soil, Cyphellophora endoradicis endophytic in roots of Microthlaspi perfoliatum, Geoglossum lauri-silvae on soil, Leptographium gemmatum from fluvial sediments, Physalacria auricularioides from a dead twig of Castanea sativa, Terfezia bertae and Tuber davidlopezii in soil. Sweden, Alpova larskersii, Inocybe alpestris and Inocybe boreogodeyi on soil. Thailand, Russula banwatchanensis, Russula purpureoviridis and Russula lilacina on soil. Ukraine, Nectriella adonidis on overwintered stems of Adonis vernalis. USA, Microcyclus jacquiniae from living leaves of Jacquinia keyensis and Penicillium neoherquei from a minute mushroom sporocarp. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Boers J, Holdom D, et al. 2022. Fungal Planet description sheets: 1383-1435. Persoonia 48: 261-371. https://doi.org/10.3767/persoonia.2022.48.08.

6.
Persoonia ; 46: 313-528, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35935893

RESUMO

Novel species of fungi described in this study include those from various countries as follows: Algeria, Phaeoacremonium adelophialidum from Vitis vinifera. Antarctica, Comoclathris antarctica from soil. Australia, Coniochaeta salicifolia as endophyte from healthy leaves of Geijera salicifolia, Eremothecium peggii in fruit of Citrus australis, Microdochium ratticaudae from stem of Sporobolus natalensis, Neocelosporium corymbiae on stems of Corymbia variegata, Phytophthora kelmanii from rhizosphere soil of Ptilotus pyramidatus, Pseudosydowia backhousiae on living leaves of Backhousia citriodora, Pseudosydowia indooroopillyensis, Pseudosydowia louisecottisiae and Pseudosydowia queenslandica on living leaves of Eucalyptus sp. Brazil, Absidia montepascoalis from soil. Chile, Ilyonectria zarorii from soil under Maytenus boaria. Costa Rica, Colletotrichum filicis from an unidentified fern. Croatia, Mollisia endogranulata on deteriorated hardwood. Czech Republic, Arcopilus navicularis from tea bag with fruit tea, Neosetophoma buxi as endophyte from Buxus sempervirens, Xerochrysium bohemicum on surface of biscuits with chocolate glaze and filled with jam. France, Entoloma cyaneobasale on basic to calcareous soil, Fusarium aconidiale from Triticum aestivum, Fusarium juglandicola from buds of Juglans regia. Germany, Tetraploa endophytica as endophyte from Microthlaspi perfoliatum roots. India, Castanediella ambae on leaves of Mangifera indica, Lactifluus kanadii on soil under Castanopsis sp., Penicillium uttarakhandense from soil. Italy, Penicillium ferraniaense from compost. Namibia, Bezerromyces gobabebensis on leaves of unidentified succulent, Cladosporium stipagrostidicola on leaves of Stipagrostis sp., Cymostachys euphorbiae on leaves of Euphorbia sp., Deniquelata hypolithi from hypolith under a rock, Hysterobrevium walvisbayicola on leaves of unidentified tree, Knufia hypolithi and Knufia walvisbayicola from hypolith under a rock, Lapidomyces stipagrostidicola on leaves of Stipagrostis sp., Nothophaeotheca mirabibensis (incl. Nothophaeotheca gen. nov.) on persistent inflorescence remains of Blepharis obmitrata, Paramyrothecium salvadorae on twigs of Salvadora persica, Preussia procaviicola on dung of Procavia sp., Sordaria equicola on zebra dung, Volutella salvadorae on stems of Salvadora persica. Netherlands, Entoloma ammophilum on sandy soil, Entoloma pseudocruentatum on nutrient poor (acid) soil, Entoloma pudens on plant debris, amongst grasses. New Zealand, Amorocoelophoma neoregeliae from leaf spots of Neoregelia sp., Aquilomyces metrosideri and Septoriella callistemonis from stem discolouration and leaf spots of Metrosideros sp., Cadophora neoregeliae from leaf spots of Neoregelia sp., Flexuomyces asteliae (incl. Flexuomyces gen. nov.) and Mollisia asteliae from leaf spots of Astelia chathamica, Ophioceras freycinetiae from leaf spots of Freycinetia banksii, Phaeosphaeria caricis-sectae from leaf spots of Carex secta. Norway, Cuphophyllus flavipesoides on soil in semi-natural grassland, Entoloma coracis on soil in calcareous Pinus and Tilia forests, Entoloma cyaneolilacinum on soil semi-natural grasslands, Inocybe norvegica on gravelly soil. Pakistan, Butyriboletus parachinarensis on soil in association with Quercus baloot. Poland, Hyalodendriella bialowiezensis on debris beneath fallen bark of Norway spruce Picea abies. Russia, Bolbitius sibiricus on à moss covered rotting trunk of Populus tremula, Crepidotus wasseri on debris of Populus tremula, Entoloma isborscanum on soil on calcareous grasslands, Entoloma subcoracis on soil in subalpine grasslands, Hydropus lecythiocystis on rotted wood of Betula pendula, Meruliopsis faginea on fallen dead branches of Fagus orientalis, Metschnikowia taurica from fruits of Ziziphus jujube, Suillus praetermissus on soil, Teunia lichenophila as endophyte from Cladonia rangiferina. Slovakia, Hygrocybe fulgens on mowed grassland, Pleuroflammula pannonica from corticated branches of Quercus sp. South Africa, Acrodontium burrowsianum on leaves of unidentified Poaceae, Castanediella senegaliae on dead pods of Senegalia ataxacantha, Cladophialophora behniae on leaves of Behnia sp., Colletotrichum cliviigenum on leaves of Clivia sp., Diatrype dalbergiae on bark of Dalbergia armata, Falcocladium heteropyxidicola on leaves of Heteropyxis canescens, Lapidomyces aloidendricola as epiphyte on brown stem of Aloidendron dichotomum, Lasionectria sansevieriae and Phaeosphaeriopsis sansevieriae on leaves of Sansevieria hyacinthoides, Lylea dalbergiae on Diatrype dalbergiae on bark of Dalbergia armata, Neochaetothyrina syzygii (incl. Neochaetothyrina gen. nov.) on leaves of Syzygium chordatum, Nothophaeomoniella ekebergiae (incl. Nothophaeomoniella gen. nov.) on leaves of Ekebergia pterophylla, Paracymostachys euphorbiae (incl. Paracymostachys gen. nov.) on leaf litter of Euphorbia ingens, Paramycosphaerella pterocarpi on leaves of Pterocarpus angolensis, Paramycosphaerella syzygii on leaf litter of Syzygium chordatum, Parateichospora phoenicicola (incl. Parateichospora gen. nov.) on leaves of Phoenix reclinata, Seiridium syzygii on twigs of Syzygium chordatum, Setophoma syzygii on leaves of Syzygium sp., Starmerella xylocopis from larval feed of an Afrotropical bee Xylocopa caffra, Teratosphaeria combreti on leaf litter of Combretum kraussii, Teratosphaericola leucadendri on leaves of Leucadendron sp., Toxicocladosporium pterocarpi on pods of Pterocarpus angolensis. Spain, Cortinarius bonachei with Quercus ilex in calcareus soils, Cortinarius brunneovolvatus under Quercus ilex subsp. ballota in calcareous soil, Extremopsis radicicola (incl. Extremopsis gen. nov.) from root-associated soil in a wet heathland, Russula quintanensis on acidic soils, Tubaria vulcanica on volcanic lapilii material, Tuber zambonelliae in calcareus soil. Sweden, Elaphomyces borealis on soil under Pinus sylvestris and Betula pubescens. Tanzania, Curvularia tanzanica on inflorescence of Cyperus aromaticus. Thailand, Simplicillium niveum on Ophiocordyceps camponoti-leonardi on underside of unidentified dicotyledonous leaf. USA, Calonectria californiensis on leaves of Umbellularia californica, Exophiala spartinae from surface sterilised roots of Spartina alterniflora, Neophaeococcomyces oklahomaensis from outside wall of alcohol distillery. Vietnam, Fistulinella aurantioflava on soil. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Cowan DA, Maggs-Kölling, et al. 2021. Fungal Planet description sheets: 1182-1283. Persoonia 46: 313-528. https://doi.org/10.3767/persoonia.2021.46.11.

7.
Luminescence ; 35(5): 781-787, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32030872

RESUMO

This study reports the structural and optical properties of CdS/ZnTiO3 nanocomposites prepared using a chemical bath and different titanate concentrations. Commercial ZnTiO3 nanoparticles were introduced into a chemical bath that had been used to produce CdS semiconductor nanoparticles (NPs). Here, the growing CdS crystallites precipitated onto the suspended zinc titanate NPs. X-ray diffraction patterns revealed that samples of CdS/ZnTiO3 nanopowders were made of cubic ZnTiO3 and hexagonal CdS wurtzite. The morphology of the particles was studied using transmission electron microscopy and scanning electron microscopy images. These images demonstrated the different characteristics of the CdS/ZnTiO3 nanocomposites and their dependence on titanate concentration when placed into the CdS-growing solution. Photoluminescence spectra showed three main emission bands for the electron transitions in the CdS/ZnTiO3 composite. This composite produced three photoluminescence bands, the intensities of which depended on composite shape, which in turn depended on the relative concentrations of CdS and ZnTiO3 .


Assuntos
Compostos de Cádmio/química , Medições Luminescentes , Nanoestruturas/química , Óxidos/química , Sulfetos/química , Titânio/química , Zinco/química , Tamanho da Partícula , Processos Fotoquímicos , Porosidade , Semicondutores , Propriedades de Superfície
8.
Clin Exp Immunol ; 198(3): 351-358, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31394007

RESUMO

In order to reset the immune system to baseline function, autologous hematopoietic stem cell transplantation (HSCT) has been performed in patients with multiple sclerosis (MS). After June 2015, 617 new consecutive patients with MS were autografted in our center with non-frozen peripheral blood stem cells. The autografts were performed on an out-patient basis, after conditioning with cyclophosphamide and rituximab. The aim of the study was the assessment of both safety and efficacy of the method. The study's primary co-end-points were recovery of granulocyte and platelet counts and transplant-related mortality. Secondary end-points were overall survival and clinical response (improvement or stabilization of the self-reported expanded disability status scale score). The protocol was registered in ClinicalTrials.gov identifier NCT02674217.0. We included 401 females and 216 males, with a median age of 46 years. A total of 259 patients had relapsing-remitting MS (RRMS), 228 had secondary progressive (SPMS) and 130 had primary progressive (PPMS) multiple sclerosis. All procedures were initially performed on an out-patient basis and only 32 individuals (5%) required hospitalization. One to three aphereses (median 1) were required to harvest at least 1 × 106 /kg viable CD34+ cells. The total number of viable CD34+ infused cells ranged between 1 and 37·83 × 106 /kg (median 5·68). Patients recovered more than 0·5 × 109 /l absolute granulocytes by day 8 (median, range = 2-14), and platelet values were above 20 × 109 /l by day 4 (median, range = 0-11). Eleven individuals required red blood cells and six needed platelet transfusions. To date, there have been no deaths attributable to the transplant, yielding a 30-month overall survival of 100%. Patients have been followed for 3-42 months (median = 12). The overall response rate (decrease or stabilization of the self-reported EDSS score) at 12 months was 78% for all patients (83% in RRMS, 78% in PPMS and 73% in SPMS), while the disability progression-free survival was 82% for all patients (86% in RRMS, 78·5% in SPMS and 78% in SPMS). Changes in the self-reported EDSS score in parallel with neurological improvement were observed in people with all types of MS after HSCT, employing the 'Mexican method'.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Esclerose Múltipla Recidivante-Remitente/terapia , Autorrelato , Condicionamento Pré-Transplante/métodos , Adulto , Idoso , Ciclofosfamida/uso terapêutico , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Rituximab/uso terapêutico , Transplante Autólogo , Resultado do Tratamento
9.
Skeletal Radiol ; 48(9): 1439-1442, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30687879

RESUMO

Congenital absence of the cruciate ligaments is a very rare condition, with most reported cases being related to the anterior cruciate ligament (ACL). Posterior cruciate ligament (PCL) congenital abnormalities have been described as almost always being associated with other anomalies. We present a case of a patient with lateral knee pain and subjective instability sensation after a low-energy trauma secondary to a lateral meniscus tear, with absence of the PCL on MRI examination and thickened meniscofemoral ligaments, with anterior and superior insertion at the femur, in the footprint of PCL. The patient had a menisci repair, without PCL reconstruction. At the 6-month follow-up, the patient did not report any instability symptoms during his daily work and sports activities. There are therapeutic implications in distinguishing a chronic PCL tear from an aplasia, so it is important to detect some signs in imaging that may guide to differentiate them, as there could be differences in the course and thickness of meniscofemoral ligaments, besides the absence of the entire PCL. To our knowledge, this is the first case of PCL agenesis with arthroscopic correlation.


Assuntos
Instabilidade Articular/cirurgia , Traumatismos do Joelho/cirurgia , Imageamento por Ressonância Magnética/métodos , Meniscos Tibiais/cirurgia , Ligamento Cruzado Posterior/anormalidades , Ligamento Cruzado Posterior/diagnóstico por imagem , Diagnóstico Diferencial , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
10.
J Biol Inorg Chem ; 23(8): 1283-1293, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30209578

RESUMO

Gold complexes are promising compounds used in cancer chemotherapy. Besides their steric features, which enable biomolecule interactions, the redox instability and the high affinity of gold with cellular nucleophiles influence the biological action in these complexes. Both features were herein theoretically investigated for the [Au(C^N^C)Cl] probe complex (C^N^C = 2,6-diphenylpyridine) using H2O, CH3SH/CH3S-, CH3Se- and meim-4-H (4-methylimidazole) as biomimetic nucleophiles. Based on the results, the lowest energy reaction path followed two consecutive steps: (1) chloride-exchange ([Formula: see text] = 4.14 × 107 M-1 s-1) and (2) reduction of the resulting Au(III) metabolite to the corresponding Au(I) analog with chelate ring-opening ([Formula: see text] =+0.15 V-data based on the reaction with CH3Se-). These findings bring new insights about the mechanism of the Au(III) complex/biomolecule interaction in the cell, which is responsible for triggering biological responses.


Assuntos
Complexos de Coordenação/química , Teoria da Densidade Funcional , Imidazóis/química , Compostos Organosselênicos/química , Compostos de Sulfidrila/química , Água/química , Ouro/química , Modelos Químicos , Oxirredução , Termodinâmica
11.
Nutr Metab Cardiovasc Dis ; 28(9): 929-936, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29739678

RESUMO

BACKGROUND & AIMS: Achieving high inter-day reliability is a key factor to analyze the magnitude of change in RMR, for instance after an intervention. The aims of this study were: i) to determine the congruent validity of RMR and respiratory quotient (RQ) with two breath by breath commercially available metabolic carts [CCM Express (CCM) and Ultima CardiO2 (MGU)]; and ii) to analyze the inter-day reliability of RMR and RQ measurements. METHODS & RESULTS: Seventeen young adults participated in the study. RMR measurements were performed during two consecutive 30-min periods, on two consecutive days with both metabolic carts. The 5-min period that met the steady state criteria [Coefficient of variance (CV) < 10% for VO2, VCO2, and VE, and CV<5% for RQ] and with the lowest CV average was included in further analysis. RMR values were higher with the MGU than with the CCM on both days (two-way ANOVA, P = 0.021), however, no differences were found on RQ values obtained by both metabolic carts (P = 0.642). Absolute inter-day RMR differences obtained with the MGU were higher than those obtained with the CCM (219 ± 185 vs. 158 ± 154 kcal/day, respectively, P = 0.002; 18.3 ± 17.2% vs. 13.5 ± 15.3%, respectively, P = 0.046). We observed a significant positive association of absolute inter-day differences in RMR obtained with both metabolic carts (ß = 0.717; R2 = 0.743; P < 0.001). CONCLUSIONS: The CCM metabolic cart provides lower RMR values and seems more reliable than the MGU in our sample of young adults. Our findings also suggest that a great part of inter-day variability is explained by the individuals.


Assuntos
Metabolismo Basal , Testes Respiratórios/instrumentação , Calorimetria Indireta/instrumentação , Adolescente , Adulto , Fatores Etários , Testes Respiratórios/métodos , Desenho de Equipamento , Feminino , Voluntários Saudáveis , Humanos , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
12.
Appl Opt ; 56(20): 5648-5654, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29047706

RESUMO

Experimental optimization of all fiber Mach-Zehnder interferometers based on concatenated tapers is presented. The experimental optimization was realized by the application of the four parameters Taguchi algorithm, and the insertion loss of comb filters operating around the 1064 nm wavelength was taken as the parameter to be optimized. The out of band losses were reduced from around 2.5 dB (43.7%) to a minimum of 0.45 dB (9.84%) in one case, and from 2.9 (48.71%) to 0.4 dB (8.79%) by using a fixed tapers pair's geometry with 1 mm×1 mm×1 mm of up-taper length/waist length/down-taper length, respectively, and a waist diameter of 40 µm.

13.
Herz ; 42(5): 449-458, 2017 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-28555288

RESUMO

Congenital disorders of lipid metabolism are caused by a wide range of variants of the genes for receptors, apolipoproteins, enzymes, transfer factors, and cellular cholesterol transporters. Clinically most relevant are autosomal dominant familial hypercholesterolemia (FH) and familial combined hyperlipoproteinemia (FCHL). FH has a prevalence of 1:250. It is due to mutations of the low density lipoprotein (LDL) receptor, less often to mutations of the apolipoprotein B (APOB), the proprotein convertase subtilisin/kexin type 9 (PCSK9), or the signal transducing adapter family member 1 (STAP1). FH often leads to early atherosclerosis. Its diagnosis can definitely be made only by molecular genetic testing. The detection of mutations of the LDLR, APOB, or PCSK9 is an indicator for extremely high cardiovascular risk, independently of the concentration of LDL cholesterol. FCHL is also common (1:100) and is seen in about 10% of patients with early myocardial infarction. It is produced by combinations of frequent genetic variants affecting triglycerides and LDL cholesterol. Other monogenic hyperlipoproteinemias (HLP) affect the catabolism of chylomicrons (familial chylomicronemia) or of remnants of triglyceride-rich lipoproteins (type III hyperlipoproteinemia). Multiple hereditary disorders in HDL metabolism - with a broad spectrum of clinical significance - are known. Currently, second generation sequencing methods are used to simultaneously analyze multiple disease-causing genes. This approach cost-neutrally provides additional information such as the genetic risk of atherosclerosis and predisposition to statin intolerance.


Assuntos
Aterosclerose/genética , Predisposição Genética para Doença/genética , Hiperlipoproteinemia Tipo II/genética , Lipoproteínas/sangue , Proteínas Adaptadoras de Transdução de Sinal/genética , Apolipoproteínas B/genética , Aterosclerose/sangue , Análise Mutacional de DNA , Humanos , Hiperlipoproteinemia Tipo II/sangue , Pró-Proteína Convertase 9/genética , Receptores de LDL/genética , Análise de Sequência de DNA
14.
Sensors (Basel) ; 17(6)2017 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-28574421

RESUMO

A compact, highly sensitive optical fiber displacement and curvature radius sensor is presented. The device consists of an adiabatic bi-conical fused fiber taper spliced to a single-mode fiber (SMF) segment with a flat face end. The bi-conical taper structure acts as a modal coupling device between core and cladding modes for the SMF segment. When the bi-conical taper is bent by an axial displacement, the symmetrical bi-conical shape of the tapered structure is stressed, causing a change in the refractive index profile which becomes asymmetric. As a result, the taper adiabaticity is lost, and interference between modes appears. As the bending increases, a small change in the fringe visibility and a wavelength shift on the periodical reflection spectrum of the in-fiber interferometer is produced. The displacement sensitivity and the spectral periodicity of the device can be adjusted by the proper selection of the SMF length. Sensitivities from around 1.93 to 3.4 nm/mm were obtained for SMF length between 7.5 and 12.5 cm. Both sensor interrogations, wavelength shift and visibility contrast, can be used to measure displacement and curvature radius magnitudes.

15.
J Phys Chem A ; 120(14): 2250-9, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27010796

RESUMO

The chemotherapy with gold complexes has been attempted since the 90s after the clinical success of auranofin, a gold(I) coordination complex. Currently, the organometallics compounds have shown promise in cancer therapy, mainly in those complexes containing N-heterocylic carbenes (NHC) as a ligand. The present study shows a kinetic analysis of the reaction of six alkyl-substituted NHC with cysteine (Cys), which is taken as an important bionucleophile representative. The first and second ligand exchange processes were analyzed with the complete description of the mechanism and energy profiles. For the first reaction step, which is the rate-limiting step of the whole substitution reaction, the activation enthalpy follows the order 1/Me2 < 2/Me,Et < 4/n-Bu2 < 3/i-Pr2 < 6/Cy2 < 5/t-Bu2, which is fully explained by steric and electronic features. From a steric point of view, the previous reactivity order is correlated with the r(Au-S) calculated for the transition state structures where S is the sulfur ligand from the Cys entering group. This means that longer r(Au-S) leads to higher activation enthalpy and is consistent with the effectiveness of gold shielding from nucleophile attack by bulkier alkyl-substituted NHC ligand. When electronic effect was addressed we found that higher activation barrier was predicted for strongly electron-donating NHC ligand, represented by the eigenvalue of σ-HOMO orbital of the free ligands. The molecular interpretation of the electronic effects is that strong donating NHC forms strong metal-ligand bond. For the second reaction step, similar structure-reactivity relationships were obtained, however the activation energies are less sensitive to the structure.


Assuntos
Cisteína/química , Ouro/química , Compostos Heterocíclicos/química , Metano/análogos & derivados , Compostos Organoáuricos/química , Ligantes , Metano/química , Estrutura Molecular , Compostos Organoáuricos/síntese química
16.
Opt Lett ; 40(7): 1468-71, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25831361

RESUMO

A compact, low loss, and highly sensitive optical fiber curvature sensor is presented. The device consists of a few-millimeter-long piece of seven-core fiber spliced between two single-mode fibers. When the optical fiber device is kept straight, a pronounced interference pattern appears in the transmission spectrum. However, when the device is bent, a spectral shift of the interference pattern is produced, and the visibility of the interference notches changes. This allows for using either visibility or spectral shift for sensor interrogation. The dynamic range of the device can be tailored through the proper selection of the length of the seven-core fiber. The effects of temperature and refractive index of the external medium on the response of the curvature sensor are also discussed. Linear sensitivity of about 3000 nm/mm(-1) for bending was observed experimentally.

17.
Adv Exp Med Biol ; 832: 9-14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25300683

RESUMO

Smoking is an important and preventable risk factor of cardiovascular diseases with effects on blood coagulation. Our aim was to analyze the influence of smoking on coagulation parameters. Concentrations or activities of blood coagulation factors were compared in 777 active smokers and 1,178 lifetime non-smokers of the Ludwigshafen Risk and Cardiovascular Health (LURIC) study. The association with mortality was examined using Cox regression. The findings show that AS had a tendency toward thrombosis. They displayed significantly higher values for fibrinogen, soluble fibrinogen, factor XIII, and tissue factor pathway inhibitor; whereas FVII, FVIII, FXII, von Willebrand factor (vWF), and thrombomodulin were decreased. The Cox regression analysis showed fibrinogen, FVIII, vWF, thrombomodulin, and tissue factor pathway inhibitor to be independent risk factors for mortality in active smokers with hazard ratios of 1.16 (95% CI: 1.02-1.31), 1.40 (1.22-1.59), 1.37 (1.22-1.56), 1.19 (1.07-1.31), and 1.22 (1.06-1.40) per increase of one standard deviation. We conclude that active smokers have an increased thrombogenic potential associated with significant changes in the coagulation system. Individual parameters of the coagulation system are independent predictors of mortality. Therefore, parameters of the coagulation system, apart from other risk factors for cardiovascular disease (e.g., lipids or life-style) should be determined for risk prediction in active smokers.


Assuntos
Fatores de Coagulação Sanguínea/metabolismo , Coagulação Sanguínea , Doenças Cardiovasculares/sangue , Fumar/efeitos adversos , Idoso , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Análise de Sobrevida
18.
Adv Exp Med Biol ; 832: 15-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25300684

RESUMO

Measurement of high sensitivity CRP (hsCRP) and lipoprotein-associated phospholipase A2 (LpPLA2) provides information on systemic inflammation and stability of atherosclerotic plaques. Data analyzing the effect of smoking on these parameters are sparse. The aim of our study was the analysis of these parameters in active smokers and never-smokers. The study included 777 smokers and 1,178 never-smokers, of whom 221 and 302 died during a follow-up, respectively. The values of LpPLA2 and hsCRP were significantly higher in smokers than in never-smokers. Mortality was highest in smokers and never-smokers with elevation of both biomarkers. Multivariate adjusted hazard ratios for patients in the highest tertile of both hsCRP and LpPLA2 compared with patients in the lowest tertile of both markers were 1.85 (1.04-3.28) in never-smokers and 1.94 (1.10-3.45) in smokers. Our data confirmed the predictive value of hsCRP and LpPLA2. However, there were a relevant number of patients with an increase of only one of these parameters. Therefore, beside other risk factors for cardiovascular disease, both parameters should be determined at least in high risk patients.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase/genética , Proteína C-Reativa/genética , Doenças Cardiovasculares/genética , Fumar/efeitos adversos , 1-Alquil-2-acetilglicerofosfocolina Esterase/sangue , Idoso , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Estudos de Casos e Controles , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Análise de Sobrevida
19.
Appl Opt ; 53(5): 944-50, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663276

RESUMO

Fiber filters based on periodic cascaded tapered fiber sections are demonstrated. The filters consist of up to seven tapered sections separated periodically by more than 3 mm from center to center, with nominal tapered sections of 1 mm×1 mm×1 mm longitudinal dimensions. The transmission spectrum consists of discrete notches, resembling those observed in long-period fiber gratings, which differs from the observed spectrum in Mach-Zender interferometers based on cascaded tapers. Its sensitivity to external perturbations, such as refractive index or mechanical stress, made the device potentially very useful as a sensor or tunable filter.

20.
J Mol Model ; 30(6): 181, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780838

RESUMO

CONTEXT: Malaria remains a significant global health challenge with emerging resistance to current treatments. Plasmodium falciparum glutathione reductase (PfGR) plays a critical role in the defense mechanisms of malaria parasites against oxidative stress. In this study, we investigate the potential of targeting PfGR with conventional antimalarials and dual drugs combining aminoquinoline derivatives with GR inhibitors, which reveal promising interactions between PfGR and studied drugs. The naphthoquinone Atovaquone demonstrated particularly high affinity and potential dual-mode binding with the enzyme active site and cavity. Furthermore, dual drugs exhibit enhanced binding affinity, suggesting their efficacy in inhibiting PfGR, where the aliphatic ester bond (linker) is essential for effective binding with the enzyme's active site. Overall, this research provides important insights into the interactions between antimalarial agents and PfGR and encourages further exploration of its role in the mechanisms of action of antimalarials, including dual drugs, to enhance antiparasitic efficacy. METHODS: The drugs were tested as PfGR potential inhibitors via molecular docking on AutoDock 4, which was performed based on the preoptimized structures in HF/3-21G-PCM level of theory on ORCA 5. Drug-receptor systems with the most promising binding affinities were then studied with a molecular dynamic's simulation on AMBER 16. The molecular dynamics simulations were performed with a 100 ns NPT ensemble employing GAFF2 forcefield in the temperature of 310 K, integration time step of 2 fs, and non-bond cutoff distance of 6.0 Å.


Assuntos
Antimaláricos , Glutationa Redutase , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Plasmodium falciparum , Antimaláricos/química , Antimaláricos/farmacologia , Plasmodium falciparum/enzimologia , Plasmodium falciparum/efeitos dos fármacos , Glutationa Redutase/antagonistas & inibidores , Glutationa Redutase/química , Glutationa Redutase/metabolismo , Ligação Proteica , Domínio Catalítico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos
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