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1.
Langmuir ; 39(21): 7353-7360, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37196166

RESUMO

N-9-Fluorenylmethyloxycarbonyl (Fmoc)- and C-tertiary butyl (t-Bu)-protected glutamate (L-2), bearing a phenanthroline moiety at the side residue, forms 1D supramolecular assemblies via H-bonding as well as undergoing π-stacking interactions to afford crystals or gels that depend on the shape-complementarity of coexisting alcohols, as demonstrated by structural analyses on these assemblies by means of single-crystal X-ray diffractometry and supplemented with small- and wide-angle X-ray scattering data. Moreover, the rheological measurements on the gels help to define a model for when gels and crystals are expected and found. These observations and conclusions highlight an important, but not very appreciated, aspect of solute-solvent interactions within supramolecular assemblies that can allow the constituent-aggregating molecules in some systems to exhibit high selectivity toward the structures of their solvents. The consequences of this selectivity, as demonstrated here by single-crystal and powder X-ray diffraction data, can lead to self-assembled structures which alter completely the bulk phase properties and morphology of the materials. In that regard, rheological measurements have helped to develop a model to explain when gels and phase-separated mixtures of crystals and solvents are expected.

2.
Arch Womens Ment Health ; 26(1): 127-134, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36472675

RESUMO

The level of support from family members-and degree of family dysfunction-can shape the onset and course of maternal postpartum depression (PPD). In spite of this, family members are typically not included in treatments for PPD. Developing and disseminating intervention approaches that involve partners or other family members may lead to more effective treatment for perinatal women and potentially promote improved family functioning and wellbeing of multiple members of the family. To evaluate the feasibility and acceptability of a family-based treatment for PPD, we conducted an open pilot trial with 16 postpartum mother-father couples (N = 32 participants) and measured session attendance, patient satisfaction, and changes in key symptoms and functional outcomes. At the time of enrollment, mothers were 1-7 months postpartum, met criteria for major depressive disorder, and had moderate-severe symptoms of depression. Treatment involved 10-12 sessions attended by the mother along with an identified family member (all fathers) at each session. Findings provide strong support for the acceptability and feasibility of the intervention: session attendance rates were high, and participants evaluated the treatment as highly acceptable. Improvements in depression were observed among both mothers and fathers, and family functioning improved by the endpoint across several domains. Symptomatic and functional gains were sustained at follow-up. The current findings provide support for a larger randomized trial of family-based treatment for PPD.


Assuntos
Depressão Pós-Parto , Transtorno Depressivo Maior , Feminino , Humanos , Gravidez , Depressão/terapia , Depressão Pós-Parto/terapia , Transtorno Depressivo Maior/terapia , Estudos de Viabilidade , Mães , Parto , Período Pós-Parto
3.
Langmuir ; 30(12): 3354-62, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24597759

RESUMO

In this contribution we show the effect of the surfactant polar head and the external solvent on the incorporation of different cyclodextrins (CDs) {α-CD, ß-CD, γ-CD, decenylsuccinyl-ß-CD (Mod-ß-CD), and hydroxypropyl-ß-CD (hp-ß-CD)} in different reverse micelles (RMs) {benzene/sodium 1,4-bis(2-ethylhexyl) sulfosuccinate(AOT)/water, and benzene/benzyl-n-hexadecyldimethylammonium chloride (BHDC)/water} and compare them with previous results obtained in n-heptane/AOT/water RMs. To investigate the different systems, we have used UV-vis spectrophotometry, induced circular dichroism spectroscopy (ICD), and the achiral molecular probe methyl orange (MO). The results show dramatic differences changing the external solvent and the surfactant, which are explained by considering the differences in the RMs interface composition, the water-surfactant interaction, and the CDs' location in the different media investigated. None of the CDs were incorporated into the benzene/AOT/water RMs at any [H2O]/[surfactant] ratio studied (W0) whereas it was previously shown that Mod-ß-CD and hp-ß-CD could be included in n-heptane/AOT/water RMs. However, all of the CDs are incorporated in benzene/BHDC/water RMs at W0 > 10 and hp-ß-CD is dissolved even at W0 = 0. Different from what was found in n-heptane/AOT RMs, in BHDC RMs MO showed ICD signals with two different CDs: Mod-ß-CD and hp-ß-CD. The results are explained by considering the known difference in the interfacial water structure for AOT and BHDC RMs and the electron-rich region on the secondary hydroxyl (wider side of the CDs), which helps to solubilize all CDs in BHDC. This study shows that chiral cyclodextrin could be available for a guest in an organic medium such as the RMs. Therefore we have created a potentially powerful nanoreactor with two different confined regions in the same aggregate: the polar core of the RMs and the chiral hydrophobic cavity of cyclodextrin.

4.
Contemp Clin Trials ; 139: 107481, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38431134

RESUMO

BACKGROUND: The transition from acute (e.g., psychiatric hospitalization) to outpatient care is associated with increased risk for rehospitalization, treatment disengagement, and suicide among people with serious mental illness (SMI). Mobile interventions (i.e., mHealth) have the potential to increase monitoring and improve coping post-acute care for this population. This protocol paper describes a Hybrid Type 1 effectiveness-implementation study, in which a randomized controlled trial will be conducted to determine the effectiveness of a multi-component mHealth intervention (tFOCUS) for improving outcomes for adults with SMI transitioning from acute to outpatient care. METHODS: Adults meeting criteria for schizophrenia-spectrum or major mood disorders (n = 180) will be recruited from a psychiatric hospital and randomized to treatment-as-usual (TAU) plus standard discharge planning and aftercare (CHECK-IN) or TAU plus tFOCUS. tFOCUS is a 12-week intervention, consisting of: (a) a patient-facing mHealth smartphone app with daily self-assessment prompts and targeted coping strategies; (b) a clinician-facing web dashboard; and, (c) mHealth aftercare advisors, who will conduct brief post-hospital clinical calls with patients (e.g., safety concerns, treatment engagement) and encourage app use. Follow-ups will be conducted at 6-, 12-, and 24-weeks post-discharge to assess primary and secondary outcomes, as well as target mechanisms. We also will assess barriers and facilitators to future implementation of tFOCUS via qualitative interviews of stakeholders and input from a Community Advisory Board throughout the project. CONCLUSIONS: Information gathered during this project, in combination with successful study outcomes, will inform a potential tFOCUS intervention scale-up across a range of psychiatric hospitals and healthcare systems. CLINICALTRIALS: govregistration: NCT05703412.


Assuntos
Esquizofrenia , Telemedicina , Adulto , Humanos , Assistência ao Convalescente , Alta do Paciente , Hospitais , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Beilstein J Org Chem ; 9: 106-17, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23400042

RESUMO

An anhydrous 1:1 crystalline inclusion complex between the organophosphorus insecticide fenitrothion [O,O-dimethyl O-(3-methyl-4-nitrophenyl)phosphorothioate] and the host compound heptakis(2,6-di-O-methyl)-ß-cyclodextrin (DIMEB) was prepared and its structure elucidated by single-crystal X-ray diffraction. This revealed two independent host molecules in the asymmetric unit. In one of these, the cavity is occupied by two disordered guest components (distinguishable as rotamers with respect to the P-OAr bond) while in the other, three distinct guest components with site-occupancies 0.44, 0.29 and 0.27 appear, the last having a reversed orientation relative to all the other components. Kinetic studies of the alkaline hydrolysis of fenitrothion in the presence of DIMEB showed a remarkable reduction of 84% in the rate of this reaction relative to that for the free substrate, a value exceeding those previously attained with the native hosts, ß- and γ-cyclodextrin, and fully methylated ß-cyclodextrin.

6.
Chemphyschem ; 13(1): 124-30, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22095797

RESUMO

We found that the absorption spectra of 2-acetylphenol (2-HAP), 4-acetylphenol (4-HAP), and p-nitrophenol (p-NPh) in water/sodium 1,4-bis(2-ethylhexyl)sulfosuccinate (AOT)/n-heptane reverse micelles (RMs) at various W(0) (W(0) = [H(2)O]/[surfactant]) values studied changed with time if (-)OH ions were present in the RM water pool. There is an evolution of ionized phenol (phenolate) bands to nonionized phenol absorption bands with time and this process is faster at low W(0) values and with phenols with higher bulk water pK(a) values. That is, in bulk water and at the hydroxide anion concentration used, only phenolate species are observed, whereas in AOT RMs at this fixed hydroxide anion concentration, ionized phenols convert into nonionized phenol species over time. Furthermore, we demonstrate that, independent of the (-)OH concentration used to prepare the AOT RMs, the nonionized phenols are the more stable species in the RM media. We explain our results by considering that strong hydrogen-bonding interactions between phenols and the AOT polar head groups result in the existence of only nonionized phenols at the AOT RM interface. The situation is quite different when the phenols are dissolved in cationic benzyl-n-hexadecyldimethylammonium chloride RMs. Therein, only phenolates species are present at the (-)OH concentrations used. The results clearly demonstrate that the classical definition of pH does not apply in a confined environment, such as in the interior of RMs and challenge the general idea that pH can be determined inside RMs.


Assuntos
Micelas , Fenol/química , Ácido Dioctil Sulfossuccínico/química , Heptanos/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Hidróxidos/química , Íons/química , Nanotecnologia , Nitrofenóis/química , Água/química
7.
Minerva Obstet Gynecol ; 74(4): 386-392, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34904586

RESUMO

Fetomaternal hemorrhage (FMH) was reported more than 60 years ago for the first time defined by the transfer or transfusion of fetal blood into the maternal circulation before or during delivery. The transfused volume is usually very small but when this value exceeds, it may be clinically significant. Antenatal diagnosis of severe FMH is difficult and it can be suspected in case of reduction of fetal movements, abnormal cardiotocography and ultrasound. FMH is associated to different adverse outcomes and admission to neonatal intensive care. The low incidence of FMH limits the studies, thus being able to rely only on diagnosis and retrospective studies. We present case series of FMH and analyze the steps with the purpose of defining a flow-chart for early diagnosis and management of FMH.


Assuntos
Transfusão Feto-Materna , Cardiotocografia , Feminino , Movimento Fetal , Transfusão Feto-Materna/diagnóstico , Humanos , Recém-Nascido , Gravidez , Diagnóstico Pré-Natal , Estudos Retrospectivos
8.
J Nerv Ment Dis ; 199(7): 449-53, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21716057

RESUMO

Previous research suggests that depression and family functioning are related and that women and men may differ in how they respond to and cope with depression. Significantly less attention has been paid to whether sex moderates the relationship between family functioning and depression. In the current study, the relationship between depression severity and perceived family functioning, both generally and in specific areas, was examined in women and men (N = 117) hospitalized with major depression. The level of depression severity was not significantly different in men and in women. Correlations between depression severity and most domains of family functioning were significant and positive for men only. Furthermore, sex statistically moderated the associations between depression severity and family functioning in the areas of problem solving, communication, affective responsiveness, and behavior control. The implications for the assessment and treatment of family dysfunction in severely depressed patients are discussed.


Assuntos
Atividades Cotidianas/psicologia , Transtorno Depressivo Maior/psicologia , Família/psicologia , Adulto , Distribuição de Qui-Quadrado , Feminino , Humanos , Relações Interpessoais , Masculino , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Fatores Sexuais
9.
Langmuir ; 26(11): 8407-13, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20205408

RESUMO

The structural orientation adopted along the compression-decompression isotherm by a monoacylated beta-cyclodextrin (C16-betaCD) at the air-water interface was assessed by polarization-modulation infrared reflection-adsorption spectroscopy (PM-IRRAS). The adoption of different orientations of the cyclic oligosaccharide unit, relative to the interfacial plane, was interpreted analyzing the PM-IRRAS band intensity ratios of specific vibrations corresponding to the cyclodextrin moiety as a function of the surface pressure for successive compression/decompression cycles. The spectroscopic analysis revealed that the cyclic oligosaccharide modifies its position under compression from one in which the plane of the cavity of the monoacylated beta-cyclodextrin lies almost parallel to the interface to another in which the plane of the cavity is perpendicular to the interface. Through the PM-IRRAS analysis, it was also possible to evidence the establishment of an intermolecular hydrogen bonding network that may play an important role in the dynamic properties of the monolayer packing. The hydrogen bonding network becomes more important with the increases of surface pressure, up to a molecular packing limit, and it imparts the surface properties of the film for future compression-decompression cycles.


Assuntos
Espectrofotometria Infravermelho/métodos , beta-Ciclodextrinas/química , Acilação , Ar , Água
10.
Langmuir ; 26(23): 17858-66, 2010 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21053985

RESUMO

The mixed system of a nonionic hydrocarbon surfactant, polyoxyethylene (23) lauryl ether (Brij-35), and a perfluorinated surfactant, perfluorononanoic acid, was investigated by a combination of methods. The critical micelle concentrations (cmc's) have been determined over a wide range of sample compositions by fluorescence and UV-visible spectrophotometry using pyrene and N-(4-nitrophenyl) perfluorononanamide, respectively, as molecular probes. The values of the cmc's obtained were considerably different with the two techniques employed. Measurements of the (19)F nuclear magnetic resonance chemical shift of the same mixtures showed two breaks in the plots of Δδ(f) versus molar fraction of the perfluorinated surfactant. Conductivity and surface tension measurements also showed two breaks. The behavior is attributed to the formation of mixed micelles that change their composition when the fraction of the fluorinated compound increases and some segregation of the fluorinated compound takes place at a high total surfactant concentration.


Assuntos
Micelas , Polietilenoglicóis/química , Tensoativos/química , Condutividade Elétrica , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos , Sondas Moleculares , Pirenos/química , Espectrometria de Fluorescência/métodos , Espectrofotometria Ultravioleta/métodos , Propriedades de Superfície , Tensão Superficial
11.
J Org Chem ; 75(10): 3427-36, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20423065

RESUMO

The reactivity of Fenitrothion (1) toward several O- and N-based nucleophiles, including ambident and alpha-nucleophiles, was investigated in basic media at 25 degrees C in water containing 2% 1,4-dioxane. In the reactions with HO(-) and HOO(-) quantitative formation of 3-methyl-4-nitrophenoxide (2) was observed indicating a S(N)2(P) pathway. In the reactions with NH(2)OH, NH(2)O(-), and BuNH(2), demethylfenitrothion (4) was formed along with 2, indicating competition between the S(N)2(P) and S(N)2(C) pathways; no evidence of a S(N)Ar pathway was observed in any case. The observed rate constants were dissected into the values corresponding to the S(N)2(P) and S(N)2(C) pathways. The yield of 4 depends on the nucleophile and on the pH of the reaction, being the main product in the case of BuNH(2). With HOO(-), NH(2)OH, and NH(2)O(-) a significant alpha-effect was observed, confirming the participation of the nucleophile in the rate-limiting step of the reaction.


Assuntos
Butilaminas/química , Fenitrotion/química , Hidrazinas/química , Peróxido de Hidrogênio/química , Hidroxilamina/química , Inseticidas/química , Concentração de Íons de Hidrogênio , Hidrólise , Água/química
12.
Phys Chem Chem Phys ; 12(25): 6616-24, 2010 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-20422106

RESUMO

Rate constants for the reversible deprotonation of (CO)(5)W=C(SR)CH(3) (W-SR) by OH(-), water and a number of primary aliphatic and secondary alicyclic amines, have been determined in 50% MeCN:50% water at 25 degrees C. In addition, solvation energy and proton affinities values for M-SR (M = Cr and W) in the gas phase and in acetonitrile have been computed at DFT level. Although there is not a linear correlation between the calculated proton affinities and the measured pK(a)s, the calculations reveal that when solvent effects are taken into account the substituted compounds studied show differences in their proton affinities. There is a good correlation between the change in cavitation energy (DeltaG(cav)) for the Fischer carbene complexes and log P of the thioalkyl substituents. In proton transfer reactions with amines, steric effects are more important for W complexes with respect to their Cr analogues as a consequence of differences in transition state progress. On the other hand, in reactions with OH(-), hydrophobicity of the R substituent is responsible for the observed changes in intrinsic kinetic acidities, which is supported by the good correlation obtained between log k(0) and log P. W complexes are more sensitive to hydrophobic effects due to the tighter solvation sphere with respect to their Cr counterparts. However, in the limit of log P = 0, the energy involved in the solvent reorganization process is the same regardless of the metal.


Assuntos
Compostos Inorgânicos de Carbono/química , Complexos de Coordenação/química , Sulfetos/química , Acetonitrilas/química , Aminas/química , Cromo/química , Gases/química , Interações Hidrofóbicas e Hidrofílicas , Cinética , Termodinâmica , Tungstênio/química
13.
J Org Chem ; 74(5): 2114-9, 2009 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-19195985

RESUMO

The physical-chemical properties of several 1,3-dithiafulvene (DTF) derivatives having a donor and acceptor group in the molecule were studied. The synthesis of these compounds produces selectively the E isomer, but when the compound is dissolved in CHCl(3) isomerization to the Z isomer takes place with a rate that depends on the substituents. The interconversion rate is slow on the NMR time scale; therefore, two separated signals are observed, and they are used to measure the rate constant of isomerization. The equilibrium constant is, in all cases, very close to 1, and this is coincident with the fact that theoretical calculations of the energy of the two isomers in the gas phase differ by less than 0.1 kcal/mol. The isomerization reaction is completely reversible, and the E isomer can be obtained in pure form by selective crystallization. The derivatives with thioalkyl groups have a strong tendency to aggregate in CDCl(3). The formation of the aggregates is evidenced from the changes in 1D (1)H NMR and DOSY spectra as a function of concentration. The compounds are highly delocalized, and this is reflected by the low activation energy for the isomerization.


Assuntos
Clorofórmio/química , Compostos Heterocíclicos com 1 Anel/química , Físico-Química , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
14.
J Org Chem ; 74(18): 7132-9, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19691326

RESUMO

The oxidation of aryl methyl sulfides containing electron withdrawing and electron donating groups (p-NO(2), p-CHO, p-NCS, p-Br, H, p-CH(3), p-OCH(3)) was carried out in homogeneous solution in acetonitrile in the presence of catalytic amounts of HNO(3) and FeBr(3). The FeBr(3) is required for the reaction to proceed for compounds with strongly electron withdrawing groups (p-NO(2) and p-CHO) but is not necessary in the case of all the other compounds, although in the latter cases the yield decreases considerably. The rate of the reaction was measured as a function of substrate, FeBr(3) and HNO(3) concentration. From the experimental data a mechanism is suggested where there are two reaction pathways, one involving the formation of a ternary complex between the substrate, FeBr(3) and NO(3)(-) and one involving a complex formed between the sulfide and the HNO(3). From these complexes HNO(2) is generated, which then combines with HNO(3) to yield N(2)O(4), initiating a catalytic cycle where the sulfide is oxidized and O(2) from the air is stoichiometrically consumed.


Assuntos
Brometos/química , Compostos Férricos/química , Ácido Nítrico/química , Sulfetos/química , Acetonitrilas/química , Catálise , Modelos Químicos , Oxirredução , Soluções/química
16.
Carbohydr Res ; 480: 12-34, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31158527

RESUMO

Cyclodextrins (CDs) are a family of biodegradable cyclic hydrocarbons composed of α-(1,4) linked glucopyranose subunits, the more common containing 6, 7 or 8 glucose units are named α, ß and γ-cyclodextrins respectively. Since the discovery of CDs, they have attracted interest among scientists and the first studies were about the properties of the native compounds and in particular their use as catalysts of organic reactions. Characteristics features of different types of cyclodextrins stimulated investigation in different areas of research, due to its non-toxic and non-inmunogenic properties and also to the development of an improved industrial production. In this way, many materials with important properties have been developed. This mini-review will focus on chemical systems that use cyclodextrins, whatever linked covalently or mediated by the non covalent interactions, to build complex systems developed mainly during the last five years.


Assuntos
Ciclodextrinas/química , Portadores de Fármacos/química , Humanos , Polímeros/química
17.
Chem Commun (Camb) ; (4): 483-5, 2008 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-18188475

RESUMO

A phenylethynyl Fischer carbene complex was used as a traceless directing group for the regioselective cycloaddition of dithiolethiones to arylacetylene, which constitutes the first synthesis of E-dithiafulvene thione or dithioesters.

19.
RSC Adv ; 8(52): 29909-29916, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35547321

RESUMO

Niosomes were prepared from equimolar mixtures of two non-ionic surfactants, Span 80 and Tween 80. The capability of the vesicular systems was studied through the encapsulation of two azo dyes as molecular probes of different hydrophobicity (methyl orange (MO) and methyl yellow (MY)). To improve the efficiency of the niosomes to encapsulate the dyes, we employed an additional modification of the vesicular system, adding ß-cyclodextrin (ß-CD) or a modified amphiphilic ß-CD (Mod-ß-CD) to the niosomes. Neither the inclusion of dyes nor the incorporation of ß-CD to the niosomes produces considerable modifications in size and morphology of the vesicles. However, in the presence of Mod-ß-CD the niosomes became smaller, probably due to the anchoring of the cyclodextrin at the surface of vesicles through the hydrophobic chain, altering the curvature of the outer monolayer and reducing the surface charge of the interphase. The entrapment efficiency (EE) for MY was higher than that for MO in niosomes without cyclodextrin, however, the content of MO in the presence of ß-CD increased considerably. Besides, the release of this dye under the same conditions was faster and reached 70% in 24 hours whereas in the absence of the macrocycle, the release was 15%, in the same time. UV-visible spectrophotometry and induced circular dichroism analysis allowed it to be established that MO is complexed with cyclodextrins inside vesicles, whereas MY interacts mainly with the niosome bilayer instead of with CD. Besides, the cavity of cyclodextrins is probably located in the interphase and preferably in the polar region of niosomes.

20.
RSC Adv ; 8(23): 12535-12539, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35541230

RESUMO

The present work shows the synthesis of a new type of catanionic surfactant, ModCD14-BHD, which involves an anionic amphiphilic cyclodextrin and the cationic benzyl-n-hexadecyldimethylammonium (BHD). It is obtained from the simple association of the cationic surfactant benzyl-n-hexadecyldimethylammonium chloride (BHDC) and ß-cyclodextrin (ß-CD) monosubstituted with an alkenyl succinate group (Mod-ß-CD14). ModCD14-BHD form unilamellar vesicles spontaneously in water, while the individual components (BHDC and Mod-ß-CD14) do not. The vesicles were character-ized by dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and 1H NMR techniques. We suggest that the formation of an inclusion complex between some of the cyclodextrins units and the long hydrocarbon moiety of the cationic surfactant play a crucial role in the vesicles formation. Besides, some or the cavities are available to interact with an external guest. We think that the new surfactant molecule has properties that may lead to important applications in biomedical and pharmaceutical sciences.

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