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1.
Molecules ; 28(13)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37446891

RESUMO

In this study, three types of sulfonic acid group functionalized ionic liquids (SAILs) with a different number of catalytic groups and lipophilicity were synthesized and characterized by FT-IR, NMR, and MS analyses. Their catalytic activities were studied in a model esterification of oleic acid with ethanol; heating in a microwave reactor was also used. The experimental results indicated that SAIL, with the lipophilic alkyl chain, performed the best due to its increased solubility in the reaction mixture. Microwave heating was found to be more effective than conventional heating. Recycling experiments show that these novel SAILs can be reused without significant loss of the catalytic activity.


Assuntos
Ácidos Graxos , Líquidos Iônicos , Esterificação , Ácidos Graxos/química , Líquidos Iônicos/química , Ácidos Sulfônicos , Espectroscopia de Infravermelho com Transformada de Fourier , Catálise
4.
Eur Arch Psychiatry Clin Neurosci ; 263(6): 475-84, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22983355

RESUMO

Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) of the left temporo-parietal cortex (LTPC) has been proposed as a useful therapeutic method for auditory hallucinations (AHs). Stereotactic neuronavigation enables the magnetic coil to be targeted according to the individual parameters obtained from neuroimaging. Individualized rTMS neuronavigated according to 18-fluorodeoxyglucose positron emission tomography ((18)FDG PET) allows us to focus the coil explicitly on a given area with detected maxima of specific abnormalities, thus presuming a higher therapeutic effect of the method. The objective of this study is to test clinical efficacy of neuronavigated LF-rTMS administered according to the local maxima of (18)FDG PET uptake of LTPC and to compare it with treatment effects of standard and sham rTMS. In a double-blind, sham-controlled design, patients with AHs underwent a 10-day series of LF-rTMS using (1) (18)FDG PET-guided "neuronavigation," (2) "standard" anatomically guided positioning, and (3) sham coil. The effect of different rTMS conditions was assessed by the Auditory Hallucinations Rating Scale (AHRS) and the Positive and Negative Syndrome Scale (PANSS). Fifteen patients were randomized to a treatment sequence and ten of them completed all three treatment conditions. The intention-to-treat analysis of AHRS score change revealed superiority of the (18)FDG PET-guided rTMS over both the standard and the sham rTMS. The analyses of the PANSS scores failed to detect significant difference among the treatments. Our data showed acute efficacy of (18)FDG PET-guided rTMS in the treatment of AHs. Neuronavigated rTMS was found to be more effective than standard, anatomically guided rTMS.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Fluordesoxiglucose F18 , Alucinações/patologia , Alucinações/terapia , Estimulação Magnética Transcraniana/métodos , Adulto , Análise de Variância , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Neuronavegação , Tomografia por Emissão de Pósitrons , Escalas de Graduação Psiquiátrica , Psicometria
5.
Int J Psychiatry Clin Pract ; 17(1): 35-43, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22486580

RESUMO

OBJECTIVE: This randomized, 6-week, open-label study compared efficacy of CAD and antidepressant monotherapies (ADM) that had been chosen according to clinical judgment of the attending psychiatrist. METHODS: A total of 60 inpatients (intent-to-treat analysis) with depressive disorder (≥ 1 unsuccessful antidepressant treatment) were randomly assigned to the interventions. The responders who completed the acute phase of study, were evaluated for relapse within 2 months of follow-up treatment. The primary outcome measure was change in the Montgomery-Åsberg Depression Rating Scale (MADRS) and response was defined as a ≥ 50% reduction of MADRS score. RESULTS: Mean changes in total MADRS score from baseline to week 6 for patients in both treatment modalities were not different (ADM = 13.2 ± 8.6 points; CAD = 14.5 ± 9.5 points; P = 0.58). The analysis of covariance performed for significantly higher value of imipramine equivalent dose in CAD group showed only a non-significant between-group difference for total MADRS change (P = 0.17). There were also no differences between groups in response rate (ADM = 48%; CAD = 58%) and number of drop-outs in acute treatment as well as proportion of responders' relapses in the follow-up. CONCLUSION: Both treatment modalities produced clinically relevant reduction of depressive symptomatology in acute treatment of patients with resistant depression and their effect was comparable.


Assuntos
Antidepressivos/administração & dosagem , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
6.
Front Psychiatry ; 14: 1127511, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37032913

RESUMO

This 8-week study was designed to explore any correlation between a passive data collection approach using a wearable device (i.e., digital phenotyping), active data collection (patient's questionnaires), and a traditional clinical evaluation [Montgomery-Åsberg Depression Rating Scale (MADRS)] in patients with major depressive disorder (MDD) treated with trazodone once a day (OAD). Overall, 11 out of 30 planned patients were enrolled. Passive parameters measured by the wearable device included number of steps, distance walked, calories burned, and sleep quality. A relationship between the sleep score (derived from passively measured data) and MADRS score was observed, as was a relationship between data collected actively (assessing depression, sleep, anxiety, and warning signs) and MADRS score. Despite the limited sample size, the efficacy and safety results were consistent with those previously reported for trazodone. The small population in this study limits the conclusions that can be drawn about the correlation between the digital phenotyping approach and traditional clinical evaluation; however, the positive trends observed suggest the need to increase synergies among clinicians, patients, and researchers to overcome the cultural barriers toward implementation of digital tools in the clinical setting. This study is a step toward the use of digital data in monitoring symptoms of depression, and the preliminary data obtained encourage further investigations of a larger population of patients monitored over a longer period of time.

7.
Nanoscale Adv ; 5(17): 4402-4414, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37638158

RESUMO

Nanodiamonds (NDs) are versatile, broadly available nanomaterials with a set of features highly attractive for applications from biology over energy harvesting to quantum technologies. Via synthesis and surface chemistry, NDs can be tuned from the sub-micron to the single-digit size, from conductive to insulating, from hydrophobic to hydrophilic, and from positively to negatively charged surface by simple annealing processes. Such ND diversity makes it difficult to understand and take advantage of their electronic properties. Here we present a systematic correlated study of structural and electronic properties of NDs with different origins and surface terminations. The absolute energy level diagrams are obtained by the combination of optical (UV-vis) and photoelectron (UPS) spectroscopies, Kelvin probe measurements, and energy-resolved electrochemical impedance spectroscopy (ER-EIS). The energy levels and density of states in the bandgap of NDs are correlated with the surface chemistry and structure characterized by FTIR and Raman spectroscopy. We show profound differences in energy band shifts (by up to 3 eV), Fermi level position (from p-type to n-type), electron affinity (from +0.5 eV to -2.2 eV), optical band gap (5.2 eV to 5.5 eV), band gap states (tail or mid-gap), and electrical conductivity depending on the high-pressure, high-temperature and detonation origin of NDs as well as on the effects of NDs' oxidation, hydrogenation, sp2/sp3 carbon phases and surface adsorbates. These data are fundamental for understanding and designing NDs' optoelectrochemical functional mechanisms in diverse application areas.

8.
Materials (Basel) ; 16(7)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37049179

RESUMO

A systematic experimental study was performed to determine laser irradiation conditions for the large-area fabrication of highly regular laser-induced periodic surface structures (HR-LIPSS) on a 220 nm thick Mo film deposited on fused silica. The LIPSS were fabricated by scanning a linearly polarized, spatially Gaussian laser beam at 1030 nm wavelength and 1.4 ps pulse duration over the sample surface at 1 kHz repetition rate. Scanning electron microscope images of the produced structures were analyzed using the criterion of the dispersion of the LIPSS orientation angle (DLOA). Favorable conditions, in terms of laser fluence and beam scanning overlaps, were identified for achieving DLOA values <10∘. To gain insight into the material behavior under these irradiation conditions, a theoretical analysis of the film heating was performed, and surface plasmon polariton excitation is discussed. A possible effect of the film dewetting from the dielectric substrate is deliberated.

9.
Atmos Chem Phys ; 22(1): 641-674, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35136405

RESUMO

Aerosol-cloud interactions (ACIs) are considered to be the most uncertain driver of present-day radiative forcing due to human activities. The nonlinearity of cloud-state changes to aerosol perturbations make it challenging to attribute causality in observed relationships of aerosol radiative forcing. Using correlations to infer causality can be challenging when meteorological variability also drives both aerosol and cloud changes independently. Natural and anthropogenic aerosol perturbations from well-defined sources provide "opportunistic experiments" (also known as natural experiments) to investigate ACI in cases where causality may be more confidently inferred. These perturbations cover a wide range of locations and spatiotemporal scales, including point sources such as volcanic eruptions or industrial sources, plumes from biomass burning or forest fires, and tracks from individual ships or shipping corridors. We review the different experimental conditions and conduct a synthesis of the available satellite datasets and field campaigns to place these opportunistic experiments on a common footing, facilitating new insights and a clearer understanding of key uncertainties in aerosol radiative forcing. Cloud albedo perturbations are strongly sensitive to background meteorological conditions. Strong liquid water path increases due to aerosol perturbations are largely ruled out by averaging across experiments. Opportunistic experiments have significantly improved process-level understanding of ACI, but it remains unclear how reliably the relationships found can be scaled to the global level, thus demonstrating a need for deeper investigation in order to improve assessments of aerosol radiative forcing and climate change.

10.
Colloids Surf B Biointerfaces ; 204: 111689, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33932892

RESUMO

Due to high biocompatibility, miniaturization, optical transparency and low production cost together with high radiation hardness the diamond-based sensors are considered promising for radiation medicine and biomedicine in general. Here we present detection of fibroblast cell culture properties by nanocrystalline diamond solution-gated field-effect transistors (SG-FET), including effects of gamma irradiation. We show that blank nanocrystalline diamond field-effect biosensors are stable at least up to 300 Gy of γ irradiation. On the other hand, gate current of the diamond SG-FET biosensors with fibroblastic cells increases exponentially over an order of magnitude with increasing radiation dose. Extracellular matrix (ECM) formation is also detected and analyzed by correlation of electronic sensor data with optical, atomic force, fluorescence, and scanning electron microscopies.


Assuntos
Técnicas Biossensoriais , Diamante , Matriz Extracelular , Fibroblastos , Microscopia Eletrônica de Varredura
11.
Sci Rep ; 11(1): 590, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33437005

RESUMO

Nanoscale composite of detonation nanodiamond (DND) and polypyrrole (PPy) as a representative of organic light-harvesting polymers is explored for energy generation, using nanodiamond as an inorganic electron acceptor. We present a technology for the composite layer-by-layer synthesis that is suitable for solar cell fabrication. The formation, pronounced material interaction, and photovoltaic properties of DND-PPy composites are characterized down to nanoscale by atomic force microscopy, infrared spectroscopy, Kelvin probe, and electronic transport measurements. The data show that DNDs with different surface terminations (hydrogenated, oxidized, poly-functional) assemble PPy oligomers in different ways. This leads to composites with different optoelectronic properties. Tight material interaction results in significantly enhanced photovoltage and broadband (1-3.5 eV) optical absorption in DND/PPy composites compared to pristine materials. Combination of both oxygen and hydrogen functional groups on the nanodiamond surface appears to be the most favorable for the optoelectronic effects. Theoretical DFT calculations corroborate the experimental data. Test solar cells demonstrate the functionality of the concept.

12.
J Org Chem ; 75(9): 3137-40, 2010 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-20392061

RESUMO

A modular synthetic approach leading to 2-aza[6]helicene is reported. It involves assembly of key hetero biphenylylnaphthalenes from functionalized building blocks and study of their metal catalyzed cycloisomerization.

14.
Cas Lek Cesk ; 149(1): 21-5, 2010.
Artigo em Tcheco | MEDLINE | ID: mdl-20662456

RESUMO

Antipsychotic medication and early relapse warning signs detection are the cornerstone of relapse prevention in schizophrenia spectrum disorders. Many patients do not use antipsychotic medication because of lack of information about its preventive effects and the risk of relapse. We introduce PREDUKA--PREventive EDUcational programme for relapse prevention. The goal of the programme is to deliver the information about schizophrenia to patients and their relatives. 178 patients and 252 relatives (118 mothers and 51 fathers) took part in 25 one-day psychoeducational programmes in 6 centres in the Czech Republic between January 2008 and June 2009 and anonymously fulfilled a short questionnaire. Patients and relatives assessed the programme with an average mark 1.4 (1 best, 5 worst). 49.4% patients and 49.0% relatives had received enough information about psychotic disorders during their hospitalization. Moreover 94.1% patients and 95.7% relatives confirmed acquiring new information on how to live with psychosis as a result of PREDUKA programme. 59.6% patients and 73.8% relatives were interested in ITAREPS - Information Technology Aided Relapse Prevention Programme. Mothers were significantly more interested (82.2%) than fathers (62.2%) (p = 0.031). Expressed high interest of patients and their relatives in both programmes indicates their readiness to become active and competent partners in the long-term treatment of schizophrenia spectrum disorders.


Assuntos
Adesão à Medicação , Pais/educação , Educação de Pacientes como Assunto , Esquizofrenia/tratamento farmacológico , Adaptação Psicológica , Avaliação Educacional , Humanos , Recidiva
15.
New Phytol ; 184(4): 932-43, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19754638

RESUMO

*Increasing evidence about hydraulic redistribution and its ecological consequences is emerging. Hydraulic redistribution results from an interplay between competing plant and soil water potential gradients. In this work, stem-mediated hydraulic redistribution was studied in a 53-year-old Douglas-fir tree during a period of drought. *Sap flux density measurements using the heat field deformation method were performed at four locations: in two large opposing roots and on two sides of the tree stem. Hydraulic redistribution was induced by localized irrigation on one of the measured roots, creating heterogeneous soil water conditions. *Stem-mediated hydraulic redistribution was detected during night-time conditions when water was redistributed from the wet side of the tree to the nonirrigated dry side. In addition to stem-mediated hydraulic redistribution, bidirectional flow in the dry root was observed, indicating radial sectoring in the xylem. *It was observed that, through stem-mediated hydraulic redistribution, Douglas-fir was unable to increase its transpiration despite the fact that sufficient water was available to one part of the root system. This resulted from the strong water potential gradient created by the dry soil in contact with the nonirrigated part of the root system. A mechanism of stem-mediated hydraulic redistribution is proposed and its possible implications are discussed.


Assuntos
Adaptação Fisiológica/fisiologia , Raízes de Plantas/fisiologia , Caules de Planta/fisiologia , Transpiração Vegetal/fisiologia , Pseudotsuga/fisiologia , Água/fisiologia , Secas , Solo , Árvores/fisiologia , Xilema
16.
J Org Chem ; 74(8): 3090-3, 2009 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-19284794

RESUMO

The new approach provides nonphotochemical syntheses of helicenes based on the easy, convergent, and modular assembly of key biphenylyl-naphthalenes and their platinum-catalyzed double cycloisomerization. This sequence of reactions provides a synthetic route to helicenes in two steps from simply accessible building blocks. Furthermore, the method enables the introduction of substituents into the hexahelicene skeleton. The strategy developed is exemplified by the synthesis of 6,10-dimethylhexahelicene and 1-methoxy-6,10-dimethylhexahelicene.

17.
Schizophr Res ; 98(1-3): 312-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17920245

RESUMO

ITAREPS presents a mobile phone-based telemedicine solution for weekly remote patient monitoring and disease management in schizophrenia and psychotic disorders in general. The programme provides health professionals with home telemonitoring via a PC-to-phone SMS platform that identifies prodromal symptoms of relapse, to enable early intervention and prevent unnecessary hospitalizations. Its web-based interface offers the authorized physician a longitudinal analysis of the dynamics and development of possible prodromes. This work presents preliminary findings from a one-year mirror-design follow-up evaluation of the programme's clinical effectiveness in 45 patients with psychotic illness. There was a statistically significant 60% decrease in the number of hospitalizations during the mean 283.3+/-111.9 days of participation in the ITAREPS, compared to the same time period before the ITAREPS entry (sign test, p<0.004). Variables significantly influencing the number of hospitalizations after the ITAREPS entry (medication compliance along with factors intrinsic to the ITAREPS, i.e. adherence to the programme and involvement of a family member) suggest a critical role of the programme in controlling the number of relapses and subsequent hospitalizations in psychosis.


Assuntos
Consulta Remota/métodos , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Telemedicina/métodos , Adulto , Antipsicóticos/uso terapêutico , Cuidadores/educação , Cuidadores/psicologia , Feminino , Hospitalização , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Cooperação do Paciente , Readmissão do Paciente , Projetos Piloto , Desenvolvimento de Programas/métodos , Avaliação de Programas e Projetos de Saúde , Esquizofrenia/tratamento farmacológico , Esquizofrenia/prevenção & controle , Prevenção Secundária , Inquéritos e Questionários , Telefone , Resultado do Tratamento
18.
J Mass Spectrom ; 53(10): 986-996, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30019544

RESUMO

Macromolecular polyelectrolytes are gaining considerable attention for the application in medicine that implies their detailed characterization. We have successfully applied electrospray ionization mass spectrometry (ESI MS) to the analysis of defects in the structure of three generations of polycationic carbosilane dendrimers bearing series of quarternary phosphonium groups at their periphery. Besides expected defects caused by incomplete conversion of particular reaction steps during the synthesis of dendritic scaffold and subsequent peripheral functionalization, also, several products of side reactions were observed together with defects created in the course of measurement (particularly ion exchange products). Defective molecules can be to some extent separated by means of gel permeation chromatography that proves that they are not products of in source fragmentation processes. Within the reaction sequence used for the synthesis of dendrimers under study, hydrosilylation was the source of most defects; the effectivity of quarternization depends on the type of phosphine. Results confirm high sensitivity of ESI MS towards defects, stability of the carbosilane skeleton towards fragmentation under the conditions of ESI ionization, and capability to detect both lower- and higher-molecular weight impurities arising from the synthetic sequence in the same m/z range as the target dendrimer, thus providing valuable view of the polydispersity.

19.
Nanotoxicology ; 12(8): 797-818, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30182770

RESUMO

Glycodendrimers (Glyco-DDMs) represent a rapidly growing class of nanoparticles with promising properties for biomedical applications but concerns regarding the impact on human health and environment are still justified. Here we report, for the first time, the comparative study of in vivo developmental toxicity of carbosilane Glyco-DDMs and their cytotoxicity in vitro. Carbosilane Glyco-DDMs (generation 1-3) containing 4, 8, and 16 ß-d-glucopyranosyl units at the periphery (DDM1Glu, DDM2Glu, and DDM3Glu) were synthesized and characterized by 1H, 13C and 29Si NMR, mass spectrometry, dynamic light scattering, atomic force microscopy (AFM), and computer modeling. In vitro cytotoxicity assay (MTT) of DDM1-3Glu was performed on three different rodent cell lines (Cricetulus griseus) - B14 (ATCC, CCL-14.1), BRL 3A (ATCC, CRL-1442), and NRK 52E (ATCC, CRL-1571). Overall, very low cytotoxicity was observed with calculated IC50 in mM range with slight difference between each cell line and DDM generation investigated. Modified fish embryo test (FET) was further used for DDM3Glu developmental toxicity testing on zebrafish (Danio rerio) embryos. While seemingly harmless to intact embryos, adverse effects of DDMs on the embryonic development become evident after chorion removal (LD50=2.78 µM at 96 hpe). We summarized that the modified FET test showed a two to three orders of magnitude difference between the in vitro cytotoxicity and in vivo developmental toxicity of DDM3Glu. While, in general, the Glyco-DDMs show great promises as efficient vectors in targeted drug delivery or as therapeutic molecules itself, we suggest that their developmental toxicity should be thoroughly investigated to exclude safety risks associated with their potential biomedical use.


Assuntos
Dendrímeros/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Silanos/toxicidade , Teratogênicos/toxicidade , Peixe-Zebra , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cricetulus , Dendrímeros/química , Glucose/química , Humanos , Dose Letal Mediana , Modelos Moleculares , Silanos/química , Propriedades de Superfície , Teratogênicos/química , Testes de Toxicidade , Peixe-Zebra/embriologia
20.
RSC Adv ; 8(58): 33276-33290, 2018 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-35548149

RESUMO

Improving the performance of p-type photoelectrodes represents a key challenge toward significant advancement in the field of tandem dye-sensitized solar cells. Herein, we demonstrate the application of boron-doped nanocrystalline diamond (B:NCD) thin films, covalently functionalized with a dithienopyrrole-benzothiadiazole push-pull chromophore, as alternative photocathodes. First, a primary functional handle is introduced on H-terminated diamond via electrochemical diazonium grafting. Afterwards, Sonogashira cross-coupling and Cu(i) catalyzed azide-alkyne cycloaddition (CuAAC) reactions are employed to attach the chromophore, enabling the comparison of the degree of surface functionalization and the importance of the employed linker at the diamond-dye interface. X-ray photoelectron spectroscopy shows that surface functionalization via CuAAC results in a slightly higher chromophore coverage compared to the Sonogashira cross-coupling. However, photocurrents and photovoltages, obtained by photoelectrochemical and Kelvin probe measurements, are approximately three times larger on photocathodes functionalized via Sonogashira cross-coupling. Surface functionalization via Sonogashira cross-coupling is thus considered the preferential method for the development of diamond-based hybrid photovoltaics.

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