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1.
Artigo em Alemão | MEDLINE | ID: mdl-32632725

RESUMO

BACKGROUND: Heat extremes are one of the most perceptible health risks of climate change. In the field of prevention, Germany relies on recommendations for heat health action plans and on programs to support such measures. OBJECTIVES: To give an overview of measures and projects for the prevention of heat-related mortality and morbidity that have been established in Germany. MATERIALS AND METHODS: Activities and projects covering heat and human health since 2003 were identified by database and Internet search. Projects just indirectly related to human health were excluded. We recorded federal states and funding agencies, and which of the eight core elements of the Federal Ministry for the Environment recommendations for action are addressed by the measure. RESULTS: Of the 190 projects, 19 can be assigned the keyword "heat health action plan", although these are very heterogeneous activities. The individual measures partly covered several criteria of the recommendations for action: 70.0% concern urban planning and construction, 37.4% information and communication, 24.2% vulnerable groups, 17.9% reducing indoor heat, 15.3% the use of a heat warning system, 13.7% each for central coordination, interdisciplinary cooperation, and the preparation of health and social systems, and 5.3% refer to monitoring and evaluation of measures. DISCUSSION: The number of measures and projects in Germany is considerable. However, it remains unclear whether these actions meet the criteria for effective medium- and short-term protection.


Assuntos
Planejamento em Saúde , Temperatura Alta , Cidades , Mudança Climática , Alemanha , Humanos
2.
Int J Hyg Environ Health ; 226: 113491, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32092491

RESUMO

Polycyclic aromatic hydrocarbons (PAH) mainly originate from incomplete combustion of organic materials and are, among other sources, found in traffic emissions, smoked or barbecued food, leafy vegetables, and tobacco smoke. Some PAH or their metabolites are hazardous for health and classified as carcinogenic, mutagenic, or toxic to reproduction. Urine samples from 3- to 17-year-old children and adolescents living in Germany were analysed for concentrations of metabolites of the PAH fluorene, naphthalene, phenanthrene, and pyrene in the population-representative German Environmental Survey for Children and Adolescents GerES V (2014-2017). PAH metabolites were analysed in urine samples of 516 participants and could be quantified in 88-100% of the samples. Geometric mean concentrations were: 0.785 µg/L (0.688 µg/gcreatinine) for 1-OH-naphthalene, 4.233 µg/L (3.706 µg/gcrea) for 2-OH-naphthalene, 0.139 µg/L (0.122 µg/gcrea) for 1-OH-phenanthrene, 0.085 µg/L (0.075 µg/gcrea) for 2-OH-phenanthrene, 0.131 µg/L (0.115 µg/gcrea) for 3-OH-phenanthrene, 0.045 µg/L (0.040 µg/gcrea) for 4-OH-phenanthrene, 0.058 µg/L (0.050 µg/gcrea) for 9-OH-phenanthrene, 0.511 µg/L (0.448 µg/gcrea) for Σ-OH-phenanthrene, and 0.099 µg/L (0.087 µg/gcrea) for 1-OH-pyrene. Analyses of subgroups revealed higher PAH metabolite concentrations in young children compared to adolescents, and also in residents of former East Germany compared to those living in former West Germany. Increased urinary PAH metabolite concentrations were found in participants using domestic fuel for heating or gas for cooking. Plastic objects were identified as another potential source of exposure. Urinary concentrations of naphthalene and fluorene metabolites were elevated in active smokers and to the same extent in non-smokers exposed to passive smoking. Comparison with previous cycles of GerES revealed a decrease over time and a further decline in the still significant differences in urinary PAH metabolite concentrations of participants living in former East versus West Germany.

3.
Pediatr Blood Cancer ; 67(2): e28064, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31736188

RESUMO

BACKGROUND: Cranial radiotherapy (RT) is associated with risk for cognitive and adaptive dysfunction. Proton RT (PRT) is a technique hypothesized to spare cognition by reducing exposure to nontarget brain tissue. However, little is known regarding functional outcomes in survivors of pediatric brain tumor (BT) treated with PRT. The present study examined the relationship between cognitive and adaptive outcomes in pediatric BT survivors post-PRT. METHODS: Survivors treated with either focal (n = 33) or craniospinal irradiation (CSI; n = 37) PRT completed neurocognitive evaluations approximately 5 years post-treatment. Results of intelligence testing and ratings of adaptive functioning are reported. Mediation models examined the relationship among radiation field, cognition, and adaptive functioning. RESULTS: The PRT CSI group demonstrated worse cognitive outcomes than the PRT Focal group across each cognitive index (Cohen's d = 0.56-0.70). Parent ratings of adaptive functioning were also worse in the PRT CSI group than the PRT Focal group (Global Adaptive Composite, d = 0.53; conceptual skills, d = 0.67). Cognitive performance fully mediated the relationship between radiation field and adaptive outcomes, while controlling for group differences in tumor histology and RT dose. CONCLUSIONS: Focal PRT survivors demonstrated generally positive outcomes with weaknesses in processing speed and aspects of adaptive functioning. CSI exposure was associated with more consistently poor cognitive and adaptive outcomes. The increased risk for adaptive dysfunction in the PRT CSI group appeared due to the effects of CSI on cognition. Efforts to reduce the volume of tissue exposure to RT remain important.


Assuntos
Atividades Cotidianas , Adaptação Psicológica , Neoplasias Encefálicas/radioterapia , Cognição/fisiologia , Radiação Cranioespinal/métodos , Terapia com Prótons/métodos , Sobreviventes/psicologia , Adolescente , Adulto , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/psicologia , Criança , Pré-Escolar , Cognição/efeitos da radiação , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Qualidade de Vida , Ajustamento Social , Adulto Jovem
4.
Nanoscale ; 11(22): 10709-10715, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31140533

RESUMO

Herein, a novel electron donor-acceptor hybrid consisting of a NIR absorbing azulenocyanine as an electron donor and few-layer graphene as an electron acceptor was prepared. The extended aromatic core of azulenocyanine (1) assists in the exfoliation of graphite and allows the formation of a very high-quality few-layer graphene azulenocyanine hybrid system (2). The formation of a stable azulenocyanine/graphene hybrid was verified by means of an arsenal of spectroscopic and microscopic techniques. Notable is the fact that the absorption spectrum recorded for 1 and likewise that for 2 covers large portions of the solar spectrum, that is, from the UV through the visible to the NIR region. In light of the latter, we incorporated 1 as well as 2 as a photosensitizer in dye sensitized solar cells (DSSCs) and probed their light harvesting. Besides an increase in the photovoltaic conversion efficiency we focused on the stability of DSSCs by preventing charge recombination between FTO and the liquid electrolyte. We used 2 as a blocking layer and in comparison with a TiCl4 pretreated blocking layer a superior conversion efficiency was realized.

5.
Pediatr Blood Cancer ; 66(9): e27800, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31134755

RESUMO

BACKGROUND: Survivors of pediatric brain tumor are at risk for adaptive difficulties. The present study examined adaptive functioning in a multiethnic sample of survivors accounting for socioeconomic status, and whether demographic, diagnostic, and/or treatment-related variables predict adaptive outcomes. METHOD: Participants included a multiethnic sample of survivors (58 Caucasian, 34 Hispanic, and 22 other non-Caucasian; M age = 14.05 years, SD = 4.33) who were approximately seven years post-treatment. Parents rated adaptive functioning and provided demographic information. Diagnostic and treatment-related information was abstracted from the electronic medical record. RESULTS: Parent ratings of adaptive functioning were similar across Caucasian, Hispanic, and other non-Caucasian survivors covarying for family income and primary caregiver education, both of which served as proxies for socioeconomic status. All ethnic groups were rated lower than the normative mean in overall adaptive functioning as well as the specific domains of conceptual, social, and practical skills. Demographic, diagnostic, and treatment-related variables were differentially associated with adaptive functioning in survivors of pediatric brain tumor, though socioeconomic status emerged as a strong significant predictor of adaptive functioning domains. CONCLUSIONS: Adaptive outcomes do not differ as a function of ethnicity after accounting for primary caregiver education and family income. Racial and ethnic minorities may be at increased risk for poorer outcomes given their overrepresentation at lower income levels. Assessing demographic and treatment-related variables early on may be helpful in identifying children likely to develop adaptive difficulties.


Assuntos
Neoplasias Encefálicas/etnologia , Sobreviventes de Câncer , Grupo com Ancestrais do Continente Europeu , Hispano-Americanos , Classe Social , Adolescente , Adulto , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Criança , Pré-Escolar , Feminino , Humanos , Masculino
6.
Neuropsychology ; 32(6): 654-663, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29939057

RESUMO

OBJECTIVE: Progress in the treatment of multiple sclerosis (MS) has resulted in larger numbers of patients living to an advanced age, but little is known about the cognitive status of these individuals. The primary purpose of this study was to identify differences in the cognitive performance between elderly individuals with MS and those with amnestic mild cognitive impairment (aMCI). METHOD: Three groups ranging in age from 60 to 80 were compared: patients with MS (n = 64), patients with aMCI (n = 58), and healthy adults (n = 70). All participants completed a standard neuropsychological test battery that evaluated domains of attention, processing speed, executive function, memory, language, and visual spatial function. RESULTS: Compared to age- and gender-matched healthy controls, elderly MS patients exhibited a pattern of cognitive impairment centering on information processing speed and memory that was consistent with the deficits observed in other studies of MS patients regardless of age. Compared to aMCI patients, the MS patients exhibited worse performance on measures of processing speed, but better performance on a measure of memory under cued conditions (Selective Reminding Test), a nonspeeded measure of language (Boston Naming Test), and measures of executive function with processing speed statistically controlled (Trail Making Test, Stroop Test). CONCLUSIONS: Differences on neuropsychological measures can serve to distinguish aMCI from MS-related cognitive impairment in older patients, but it is essential that these measures control for the deficit in processing speed that is such a primary feature of MS. (PsycINFO Database Record


Assuntos
Envelhecimento/fisiologia , Amnésia/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Esclerose Múltipla/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Nanoscale ; 9(32): 11632-11639, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28770927

RESUMO

We have performed the syntheses of a novel pyrene-porphyrazine conjugate (ZnPzPy) and a reference porphyrazine (ZnPz) to promote the wet-chemical exfoliation of graphite based on the synergetic use of ultrasonication, centrifugation, and doping. ZnPzPy features, on one hand, a hydrophobic pyrene to anchor onto the basal plane of graphene, and, on the other hand, an amphoteric porphyrazine to either p- or n-dope graphene. To this end, we have characterized individual building blocks, that is, ZnPzPy and exfoliated graphite, and the resulting electron donor-acceptor nanohybrid, that is, ZnPzPy/graphene (ZnPzPy-G), by means of an arsenal of microscopic and spectroscopic techniques. From a full-fledged characterization we conclude that ZnPzPy facilitates the exfoliation of graphite affording suspensions featuring 9.5% of single- or few-layered ZnPzPy-G with a mean average size of 200 ± 140 nm. Importantly, a notable shift of charge density from graphene to ZnPzPy in the ground state of ZnPzPy-G corroborates the preference of exfoliated graphite to undergo p-doping rather than n-doping. As an immediate consequence, a full charge separation leads in the excited state to a 750 ± 150 ps lived charge separated state.

9.
Nat Med ; 23(7): 815-817, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28604701

RESUMO

The potential of bispecific T cell-engaging antibodies is hindered by manufacturing challenges and short serum half-life. We circumvented these limitations by treating mice with in vitro-transcribed pharmacologically optimized, nucleoside-modified mRNA encoding the antibody. We achieved sustained endogenous synthesis of the antibody, which eliminated advanced tumors as effectively as the corresponding purified bispecific antibody. Because manufacturing of pharmaceutical mRNA is fast, this approach could accelerate the clinical development of novel bispecific antibodies.


Assuntos
Anticorpos Biespecíficos/genética , Citocinas/efeitos dos fármacos , Neoplasias/terapia , RNA Mensageiro/farmacologia , Linfócitos T/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos , Animais , Anticorpos Biespecíficos/imunologia , Linhagem Celular Tumoral , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Immunoblotting , Imuno-Histoquímica , Técnicas In Vitro , Medições Luminescentes , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Neoplasias/imunologia , Neoplasias/patologia , RNA Mensageiro/genética , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Chem Sci ; 8(5): 3494-3499, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28507723

RESUMO

N,N'-Didodecyl-substituted 3,10-diazapicenium salts featuring bromide and hexafluorophosphate counterions have been designed as novel dopants to realize individualized graphene sheets in a series of cutting edge experiments and to intrinsically stabilize them via p-doping. Importantly, electrochemical studies revealed two consecutive irreversible one-electron reductions of the N,N'-didodecyl-substituted 3,10-diazapicenium salts to yield the corresponding radical cation and neutral quinoidal species. Formation of both species was accompanied by characteristic changes in the absorption spectra. The 3,10-diazapicenium bromide was found to be a potent dopant to produce hybrid materials with exfoliated graphene. Microscopy based on AFM and TEM imaging and spectroscopy based on Raman probing corroborated that, upon drying, the hybrid material consists of few layer (5-8 layers) turbostratic graphene sheets that are p-doped. Our findings identify the newly synthesized N,N'-dialkylated 3,10-diazapicenium salts as highly promising candidates for the fabrication of functional graphene materials with tailored properties.

11.
Lancet Infect Dis ; 17(6): 636-644, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28363637

RESUMO

BACKGROUND: A drug for causal (ie, pre-erythrocytic) prophylaxis of Plasmodium falciparum malaria with prolonged activity would substantially advance malaria control. DSM265 is an experimental antimalarial that selectively inhibits the parasite dihydroorotate dehydrogenase. DSM265 shows in vitro activity against liver and blood stages of P falciparum. We assessed the prophylactic activity of DSM265 against controlled human malaria infection (CHMI). METHODS: At the Institute of Tropical Medicine, Eberhard Karls University (Tübingen, Germany), healthy, malaria-naive adults were allocated to receive 400 mg DSM265 or placebo either 1 day (cohort 1A) or 7 days (cohort 2) before CHMI by direct venous inoculation (DVI) of 3200 aseptic, purified, cryopreserved P falciparum sporozoites (PfSPZ Challenge; Sanaria Inc, Rockville, MD, USA). An additional group received daily atovaquone-proguanil (250-100 mg) for 9 days, starting 1 day before CHMI (cohort 1B). Allocation to DSM265, atovaquone-proguanil, or placebo was randomised by an interactive web response system. Allocation to cohort 1A and 1B was open-label, within cohorts 1A and 2, allocation to DSM265 and placebo was double-blinded. All treatments were given orally. Volunteers were treated with an antimalarial on day 28, or when parasitaemic, as detected by thick blood smear (TBS) microscopy. The primary efficacy endpoint was time-to-parasitaemia, assessed by TBS. All participants receiving at least one dose of chemoprophylaxis or placebo were considered for safety, those receiving PfSPZ Challenge for efficacy analyses. Log-rank test was used to compare time-to-parasitemia between interventions. The trial was registered with ClinicalTrials.gov, number NCT02450578. FINDINGS: 22 participants were enrolled between Oct 23, 2015, and Jan 18, 2016. Five participants received 400 mg DSM265 and two participants received placebo 1 day before CHMI (cohort 1A), six participants received daily atovaquone-proguanil 1 day before CHMI (cohort 1B), and six participants received 400 mg DSM265 and two participants received placebo 7 days before CHMI (cohort 2). Five of five participants receiving DSM265 1 day before CHMI and six of six in the atovaquone-proguanil cohort were protected, whereas placebo recipients (two of two) developed malaria on days 11 and 14. When given 7 days before CHMI, three of six volunteers receiving DSM265 became TBS positive on days 11, 13, and 24. The remaining three DSM265-treated, TBS-negative participants of cohort 2 developed transient submicroscopic parasitaemia. Both participants receiving placebo 7 days before CHMI became TBS positive on day 11. The only possible DSM265-related adverse event was a moderate transient elevation in serum bilirubin in one participant. INTERPRETATION: A single dose of 400 mg DSM265 was well tolerated and had causal prophylactic activity when given 1 day before CHMI. Future trials are needed to investigate further the use of DSM265 for the prophylaxis of malaria. FUNDING: Global Health Innovative Technology Fund, Wellcome Trust, Bill & Melinda Gates Foundation through Medicines for Malaria Venture, and the German Center for Infection Research.


Assuntos
Antimaláricos/administração & dosagem , Quimioprevenção , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/imunologia , Pirimidinas/administração & dosagem , Triazóis/administração & dosagem , Administração Intravenosa , Adolescente , Adulto , Antimaláricos/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Parasitemia/imunologia , Parasitemia/parasitologia , Pirimidinas/uso terapêutico , Esporozoítos/imunologia , Triazóis/uso terapêutico , Voluntários
13.
Nat Microbiol ; 2: 16188, 2016 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-27748756

RESUMO

Helicobacter pylori (Hp) strains that carry the cag type IV secretion system (cag-T4SS) to inject the cytotoxin-associated antigen A (CagA) into host cells are associated with peptic ulcer disease and gastric adenocarcinoma. CagA translocation by Hp is mediated by ß1 integrin interaction of the cag-T4SS. However, other cellular receptors or bacterial outer membrane adhesins essential for this process are unknown. Here, we identify the HopQ protein as a genuine Hp adhesin, exploiting defined members of the carcinoembryonic antigen-related cell adhesion molecule family (CEACAMs) as host cell receptors. HopQ binds the amino-terminal IgV-like domain of human CEACAM1, CEACAM3, CEACAM5 or CEACAM6 proteins, thereby enabling translocation of the major pathogenicity factor CagA into host cells. The HopQ-CEACAM interaction is characterized by a remarkably high affinity (KD from 23 to 268 nM), which is independent of CEACAM glycosylation, identifying CEACAMs as bona fide protein receptors for Hp. Our data suggest that the HopQ-CEACAM interaction contributes to gastric colonization or Hp-induced pathologies, although the precise role and functional consequences of this interaction in vivo remain to be determined.


Assuntos
Adesinas Bacterianas/metabolismo , Antígenos de Bactérias/metabolismo , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Moléculas de Adesão Celular/metabolismo , Helicobacter pylori/fisiologia , Interações Hospedeiro-Patógeno , Transporte Proteico , Linhagem Celular , Humanos , Ligação Proteica
14.
J Am Chem Soc ; 138(36): 11445-8, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27523161

RESUMO

The structure of graphene oxide (GO) is a matter of discussion. While established GO models are based on functional groups attached to the carbon framework, another frequently used model claims that GO consists of two components, a slightly oxidized graphene core and highly oxidized molecular species, oxidative debris (OD), adsorbed on it. Those adsorbents are claimed to be the origin for optical properties of GO. Here, we examine this model by preparing GO with a low degree of functionalization, combining it with OD and studying the optical properties of both components and their combination in an artificial two-component system. The analyses of absorption and emission spectra as well as lifetime measurements reveal that properties of the combined system are distinctly different from those of GO. That confirms structural models of GO as a separate oxygenated hexagonal carbon framework with optical properties governed by its internal structure rather than the presence of OD. Understanding the structure of GO allows further reliable interpretation of its optical and electronic properties and enables controlled processing of GO.

15.
J Clin Exp Neuropsychol ; 37(5): 518-29, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26010017

RESUMO

OBJECTIVE: The Attention Network Test (ANT) assesses attention in terms of discrepancies between response times to items that differ in the burden they place on some facet of attention. However, simple arithmetic difference scores commonly used to capture these discrepancies fail to provide adequate control for information processing speed, leading to distorted findings when patient and control groups differ markedly in the speed with which they process and respond to stimulus information. This study examined attention networks in patients with multiple sclerosis (MS) using simple difference scores, proportional scores, and residualized scores that control for processing speed through statistical regression. METHOD: Patients with relapsing-remitting (N = 20) or secondary progressive (N = 20) MS and healthy controls (N = 40) of similar age, education, and gender completed the ANT. RESULTS: Substantial differences between patients and controls were found on all measures of processing speed. Patients exhibited difficulties in the executive control network, but only when difference scores were considered. When deficits in information processing speed were adequately controlled using proportional or residualized score, deficits in the alerting network emerged. The effect sizes for these deficits were notably smaller than those for overall information processing speed and were also limited to patients with secondary progressive MS. CONCLUSIONS: Deficits in processing speed are more prominent in MS than those involving attention, and when the former are properly accounted for, differences in the latter are confined to the alerting network.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Processos Mentais/fisiologia , Esclerose Múltipla/complicações , Testes Neuropsicológicos , Adulto , Análise de Variância , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia
16.
Arch Clin Neuropsychol ; 30(4): 322-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25857404

RESUMO

The Symbol--Digit Modalities Test (SDMT) is widely used to assess processing speed in MS patients. We developed a computerized version of the SDMT (c-SDMT) that scored participants' performance during subintervals over the course of the usual 90-s time period and also added an incidental learning test (c-ILT) to assess how well participants learned the symbol-digit associations while completing the c-SDMT. Patients with MS (n = 65) achieved lower scores than healthy controls (n = 38) on both the c-SDMT and c-ILT, and the scores on the two tests were correlated. However, no increase in the rate of item completion occurred for either group over the course of the c-SDMT, and the difference between groups was the same during each subinterval. Therefore, it seems implausible that controls completed more items on the c-SDMT because they were more adept at learning the symbol-digit associations as the test ensued. Instead, MS patients' poorer incidental learning performance appears to reflect the greater attentional burden that tasks requiring rapid serial processing of information impose upon them.


Assuntos
Transtornos Cognitivos/fisiopatologia , Aprendizagem/fisiologia , Esclerose Múltipla/fisiopatologia , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Adulto , Idoso , Associação , Transtornos Cognitivos/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações
17.
Nanoscale ; 7(13): 5674-82, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-25740090

RESUMO

We describe herein the preparation of novel exfoliated graphene-phthalocyanine nanohybrids, and the investigation of their photophysical properties. Pyridyl-phthalocyanines (Pcs) are presented as novel electron accepting building blocks of variable strengths with great potential for the exfoliation of graphite via their immobilization onto the basal plane of graphene in dimethylformamide (DMF) affording single layered and turbostratic graphene based . were fully characterized (AFM, TEM, Raman, steady-state and pump probe transient absorption spectroscopy) and were studied in terms of electron donor-acceptor interactions in the ground and excited states. In this context, electron transfer upon photoexcitation from graphene to the electron accepting Pcs with dynamics, for example, in of <1 and 330 ± 50 ps for charge separation and charge recombination, respectively, was corroborated in a series of steady-state and time-resolved spectroscopy experiments.

18.
Am J Clin Nutr ; 101(2): 287-93, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25646325

RESUMO

BACKGROUND: A reduction in key antioxidants such as glutathione has been noted in brain tissue undergoing oxidative stress in aging and neurodegeneration. To date, no dietary factor has been linked to a higher glutathione concentration. However, in an earlier pilot study, we showed evidence of a positive association between cerebral glutathione and dairy intake. OBJECTIVE: We tested the hypothesis that dairy food consumption is associated with cerebral glutathione concentrations in older adults. DESIGN: In this observational study, we measured cerebral glutathione concentrations in 60 healthy subjects (mean ± SD age: 68.7 ± 6.2 y) whose routine dairy intakes varied. Glutathione concentrations were measured by using a unique, noninvasive magnetic resonance chemical shift imaging technique at 3 T and compared with dairy intakes reported in 7-d food records. RESULTS: Glutathione concentrations in the frontal [Spearman's rank-order correlation (rs) = 0.39, P = 0.013], parietal (rs = 0.50, P = 0.001), and frontoparietal regions (rs = 0.47, P = 0.003) were correlated with average daily dairy servings. In particular, glutathione concentrations in all 3 regions were positively correlated with milk servings (P ≤ 0.013), and those in the parietal region were also correlated with cheese servings (P = 0.015) and calcium intake (P = 0.039). Dairy intake was related to sex, fat-free mass, and daily intakes of energy, protein, and carbohydrates. However, when these factors were controlled through a partial correlation, correlations between glutathione concentrations and dairy and milk servings remained significant. CONCLUSIONS: Higher cerebral glutathione concentrations were associated with greater dairy consumption in older adults. One possible explanation for this association is that dairy foods may serve as a good source of substrates for glutathione synthesis in the human brain.


Assuntos
Cérebro/química , Laticínios , Dieta , Glutationa/química , Idoso , Idoso de 80 Anos ou mais , Estatura , Peso Corporal , Cálcio na Dieta/administração & dosagem , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Política Nutricional , Circunferência da Cintura
19.
Neurosci Lett ; 585: 109-13, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25433180

RESUMO

Fragile X syndrome (FXS), a disorder caused by a mutation in the FMR1 gene, is often associated with Attention Deficit Hyperactivity Disorder (ADHD). Common treatments for the hyperactivity often seen in ADHD involve the use of stimulants and α2-adrenergic agonists. The Fmr1 knockout (KO) mouse has been found to be a valid model for FXS both biologically and behaviorally. Of particular interest to our research, the Fmr1 KO mouse has been demonstrated to show increased locomotion in comparison to wild type (WT) littermates. In the present study, we assessed the effects of clonidine (0.05 mg/kg) and methylphenidate (5 mg/kg) on motor activity in Fmr1 KO mice and their WT littermates in the open field test. Results showed that methylphenidate increased motor activity in both genotypes. Clonidine decreased motor activity in both genotypes, but the effect was delayed in the Fmr1 KO mice.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Clonidina/farmacologia , Proteína do X Frágil de Retardo Mental/genética , Metilfenidato/farmacologia , Atividade Motora/efeitos dos fármacos , Agonistas de Receptores Adrenérgicos alfa 2/uso terapêutico , Animais , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Clonidina/uso terapêutico , Síndrome do Cromossomo X Frágil/tratamento farmacológico , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/psicologia , Metilfenidato/uso terapêutico , Camundongos Knockout
20.
J Am Chem Soc ; 136(12): 4593-8, 2014 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-24568604

RESUMO

We describe herein the first example of highly exfoliated graphene covalently linked to electron accepting phthalocyanines. The functionalization of the nanocarbon surface with alkylsulfonyl phthalocyanines was attained by means of a "click" chemistry protocol. The new ensemble was fully characterized (thermogravimetric analysis, atomic force microscopy, transmission electron microscopy and Raman, as well as ground-state absorption) and was studied in terms of electron donor-acceptor interactions in the ground and in the excited state. In particular, a series of steady-state and time-resolved spectroscopy experiments demonstrated photoinduced electron transfer from the graphene to the electron-accepting phthalocyanines. This is the first example of an electron donor-acceptor nanoconjugate, that is, few-layer graphene/phthalocyanine, pinpointing the uncommon electron donating character of graphene.

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