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1.
Carbohydr Polym ; 334: 122007, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38553199

ABSTRACT

Pectins are dietary fibers that are attributed with several beneficial immunomodulatory effects. Depending on the degree of esterification (DE), pectins can be classified as high methoxyl pectin (HMP) or low methoxyl pectin (LMP). The aim of this study was to investigate the effects of pectin methyl-esterification on intestinal microbiota and its immunomodulatory properties in naive mice. Supplementation of the diet with LMP or HMP induced changes in the composition of the intestinal microbiota in mice toward Bacteroides, which was mainly promoted by HMP. Metabolome analysis of stool samples from pectin-fed mice showed a different effect of the two types of pectin on the levels of short-chain fatty acids and bile acids, which was consistent with highly efficient in vivo fermentation of LMP. Analysis of serum antibody levels showed a significant increase in IgG and IgA levels by both pectins, while FACS analysis revealed a decrease of infiltrating inflammatory cells in the intestinal lamina propria by HMP. Our study revealed that the structural properties of the investigated pectins determine fermentability, effects on microbial composition, metabolite production, and modulation of immune responses. Consumption of HMP preferentially altered the gut microbiota and suppressed pro-inflammatory immune responses, suggesting a beneficial role in inflammatory diseases.


Subject(s)
Gastrointestinal Microbiome , Pectins , Mice , Animals , Pectins/chemistry , Esterification , Dietary Fiber/pharmacology , Dietary Fiber/metabolism , Fermentation
2.
Carbohydr Polym ; 308: 120642, 2023 May 15.
Article in English | MEDLINE | ID: mdl-36813335

ABSTRACT

Many of the proposed health-related properties of pectins are based on their fermentability in the large intestine, but detailed structure-related studies on pectin fermentation have not been reported so far. Here, pectin fermentation kinetics were studied with a focus on structurally different pectic polymers. Therefore, six commercial pectins from citrus, apple, and sugar beet were chemically characterized and fermented in in vitro fermentation assays with human fecal samples over different periods of time (0 h, 4 h, 24 h, 48 h). Structure elucidation of intermediate cleavage products showed differences in fermentation speed and/or fermentation rate among the pectins, but the order in which specific structural pectic elements were fermented was comparable across all pectins. Neutral side chains of rhamnogalacturonan type I were fermented first (between 0 and 4 h), followed by homogalacturonan units (between 0 and 24 h) and, at last, the rhamnogalacturonan type I backbone (between 4 and 48 h). This indicates that fermentation of different pectic structural units might take place in different sections of the colon, potentially affecting their nutritional properties. For the formation of different short-chain fatty acids, mainly acetate, propionate, and butyrate, and the influence on microbiota, there was no time-dependent correlation regarding the pectic subunits. However, an increase of members of the bacterial genera Faecalibacterium, Lachnoclostridium, and Lachnospira was observed for all pectins.


Subject(s)
Pectins , Rhamnogalacturonans , Humans , Fermentation , Pectins/chemistry , Feces/microbiology , Bacteria/metabolism
3.
Pharmaceutics ; 14(4)2022 Mar 26.
Article in English | MEDLINE | ID: mdl-35456544

ABSTRACT

This research reports accelerated stability experiments, the evaluation of intermolecular interactions, and antifungal assays for fluconazole emulsions prepared using ultrasound (US) and magnetic stirring (MS) in the presence of ionic liquids derived from 1,n-(3-methylimidazolium-1-yl)alkane bromide ([CnMIM]Br; n = 12 or 16). The goals of the investigation are to quantify the stability, identify the forces that drive the formation and stability, and determine the antifungal activity of fluconazole-containing emulsions, and corroborate the data from our previous results that indicated that the emulsion based on [C16MIM]Br seemed to be more stable. In this study, accelerated stability experiments evidenced a considerable stability for the [C16MIM]Br emulsions at two temperatures (25 and 37 °C)­the instability index increased in the following order: US40% < US20% < MS. The 1H NMR data showed that the ILs interacts differently with medium-chain triglycerides (MCT). Two distinct interaction mechanisms were also observed for [C12MIM]Br and [C16MIM]Br with fluconazole, in which the latter formed more compact mixed aggregates than the former. The result was corroborated by diffusion data, which showed that ILs suffered a decrease in diffusion in the presence of fluconazole. The antifungal assay showed that emulsions containing ILs displayed superior activity compared with fluconazole alone. The emulsions also showed potent activity in inhibiting a resistant species (C. glabrata­CG34) to FLZ. All emulsions showed weak irritant potential in HET-CAM assay.

4.
Article in English | LILACS | ID: biblio-1403718

ABSTRACT

Abstract The new coronavirus pandemic (COVID-19) is a global problem that is having severe impacts on health systems worldwide. One particular characteristic of this virus is its high transmission rate, which has led to a high demand for personal care materials such as masks, gloves, and alcohol for asepsis. Seventy percent is the ideal concentration for the ethanol used in hand sanitizers; however, this concentration can be expressed in different ways, and, consequently, the different solutions will have different antiseptic activity. In this manuscript we comment on some characteristics of alcohol-based preparations and the different ways of expressing the concentrations.


Subject(s)
Coronavirus , Ethanol/adverse effects , Hand Sanitizers/analysis , COVID-19/prevention & control , Asepsis , Personal Hygiene Products , Pandemics , Masks/classification
5.
Foods ; 11(1)2021 Dec 21.
Article in English | MEDLINE | ID: mdl-35010137

ABSTRACT

Pectin, a dietary fiber, is a polysaccharide that is widely used in food industry as a gelling agent. In addition, prebiotic and beneficial immunomodulatory effects of pectin have been demonstrated, leading to increased importance as food supplement. However, as cases of anaphylactic reactions after consumption of pectin-supplemented foods have been reported, the present study aims to evaluate the allergy risk of pectin. This is of particular importance since most of the pectin used in the food industry is extracted from citrus or apple pomace. Both contain several allergens such as non-specific lipid transfer proteins (nsLTPs), known to induce severe allergic reactions, which could impair the use of pectins in nsLTP allergic patients. Therefore, the present study for the first time was performed to analyze residual nsLTP content in two commercial pectins using different detection methods. Results showed the analytical sensitivity was diminished by the pectin structure. Finally, spiking of pectin with allergenic peach nsLTP Pru p 3 led to the conclusion that the potential residual allergen content in both pectins is below the threshold to induce anaphylactic reactions in nsLTP-allergic patients. This data suggests that consumption of the investigated commercial pectin products provides no risk for inducing severe reactions in nsLTP-allergic patients.

6.
ACS Omega ; 4(6): 9697-9709, 2019 Jun 30.
Article in English | MEDLINE | ID: mdl-31460060

ABSTRACT

A systematic investigation to assess the degree of similarity between polymorphs was carried out. A similarity indices (IX) approach was applied in ten series of polymorphs with different characteristics and number of molecules in the asymmetric unit. Geometric (ID), contact area (IC), and stabilization energy (IG) parameters were used. It was possible to situate each comparison in different regions of similarity within the polymorphism phenomenon and determine the boundaries between quasi-isostructural polymorphs and polymorphs of low similarity. The multiparameter IDCG index was used as a robust tool to determine the total similarity within the polymorphism phenomenon. The highest contribution of the stabilization energy parameter (45%) toward the final value of similarity (IDCG) was observed, followed by the contact area index (32%). The geometric index contributed approximately 23% to the final value of IDCG. This information reinforces the importance of the contact area and stabilization energy in assessing the degree of similarity between crystalline structures. A new descriptor (IQ) based on the comparison of the energetic contribution of intermolecular interaction types present in each crystal structure is presented. IQ can be a versatile tool and applicable even for systems that do not share any similarity.

7.
Mater Sci Eng C Mater Biol Appl ; 100: 48-61, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30948084

ABSTRACT

Dronedarone is a new antiarrhythmic drug for the treatment of atrial fibrillation. This study investigated the complexation of dronedarone hydrochloride with ß­cyclodextrin (ß-CD) and 2­hydroxypropil­ß­CD (HP-ß-CD) using three different techniques. The complexes in the solid state were characterized by DSC, TGA, PXRD, FT-IR, SEM and 1H NMR, demonstrating the formation of the inclusion complexes and exhibiting different properties from the pure drug. Its aqueous solubility increased about 4.0-fold upon complexation with ß-CD and HP-ß-CD. The dissolution rate of the drug was notably improved in all tested physiological pH values from 1.2 to 6.8 in the presence of both cyclodextrins. Furthermore, an in vitro cytotoxic assay revealed that the inclusion complexes could reduce the cytotoxic effects of the drug on 3T3 cells. The overall results suggest that the inclusion complexes with ß-CD and HP-ß-CD may be potentially useful in the preparation of novel pharmaceutical formulations containing dronedarone hydrochloride.


Subject(s)
Anti-Arrhythmia Agents/chemistry , Dronedarone/chemistry , beta-Cyclodextrins/chemistry , 2-Hydroxypropyl-beta-cyclodextrin/chemistry , 3T3 Cells , Animals , Anti-Arrhythmia Agents/chemical synthesis , Anti-Arrhythmia Agents/pharmacology , Cell Survival/drug effects , Dronedarone/chemical synthesis , Dronedarone/pharmacology , Drug Compounding , Freeze Drying , Mice , Microscopy, Electron, Scanning , Solubility , Spectroscopy, Fourier Transform Infrared , Thermogravimetry , X-Ray Diffraction
8.
Carbohydr Polym ; 214: 174-185, 2019 Jun 15.
Article in English | MEDLINE | ID: mdl-30925987

ABSTRACT

Thermoreversible hydrogels are suitable in food products in order to improve texture and in biomedical applications as drug delivery vehicles. The properties of hydrogels affect their performance in those applications. In this paper, it is presented the effect of mono- (CnMIMBr) and dicationic (Cn(MIM)2Br2) imidazolium ionic liquids (ILs) on the viscosity and gelation of methylcellulose (MC) using rheology, micro differential scanning calorimetric and small angle X-ray scattering (SAXS) techniques. Results show that the ILs affect the pattern of the sol-gel transition and display transition from the salt-out to the salt-in on the gelation temperature, decrease the gel strength and increase viscosity of MC solutions. This behavior can be explained by hydrophobic interaction between the ILs and the MC, which depends of the alkyl chain length of the ILs, type of ILs (conventional or bolaform) and the range of ILs concentration. In general, the presence of ILs decrease the MC gel strength, while dicationic ILs hampers their association on MC in comparison with monocationic ones. The findings highlight the role of ILs on gelation of MC opening possibilities for the design of new complex formulations.

9.
Soft Matter ; 14(32): 6716-6727, 2018 Aug 15.
Article in English | MEDLINE | ID: mdl-30062361

ABSTRACT

Supramolecular gels present several applications in which the gelator properties are closely dependent on their structure and solvent. Despite this, there are few studies on the effect of the gelation ability of gelators with slight molecular changes. Therefore, N-arylestearamides (in which aryl = phenyl (1), 4-tolyl (2) and 4-acetylphenyl (3)) were evaluated in different solvents. The critical gelefication concentration (CGC) values indicated that the substituents can significantly affect the concentration at which the supramolecular gels are formed, mainly in non-aromatic solvents (e.g. cyclohexane, acetonitrile and DMSO). From UV-Vis and DSC data, we verified that the gel-sol and sol-gel transitions (Tgel-sol and Tsol-gel) increase in the order of 1 < 2 < 3. Organogel strength was evaluated for 1-3 as a function of concentration and solvent type using rheology data. Gel strength is concentration-dependent and a strength order was found in acetonitrile, cyclohexane and DMSO, in which: 1 ∼ 2 > 3. Dynamic viscoelastic measurements as a function of temperature sweeps indicate a predominantly enthalpic contribution to the elasticity of the organogels formed from 1-3. Temperature-dependent 1H NMR indicates that NHO interactions may be responsible for the molecular association of molecules into 1D fibers, while 3D fibers were formed from van der Waals interactions.

10.
ACS Omega ; 3(1): 734-743, 2018 Jan 31.
Article in English | MEDLINE | ID: mdl-30023787

ABSTRACT

Partition constants (KD°), molecular dynamics (T1, T2, and DOSY measurements), thermal stability, and toxicity of dicationic ionic liquids (ILs) were determined. The dicationic ILs derived from 1,n-bis(3-methylimidazolim-1-yl)octane, [BisOct(MIM)2][2X] (in which X = Cl, Br, NO3, SCN, BF4, and NTf2), were evaluated to verify the influence of anion structure on the IL properties. A monocationic IL [Oct(MIM)][Br] was also monitored for comparison. In general, the solubility of the ILs followed the anion free energy of hydration (ΔG°hyd). The thermokinetic and thermodynamic functions of activation of the ILs were determined via thermogravimetric data, and it was observed that polyatomic anions influence the decomposition mechanism of these IL structures. Furthermore, [Oct(MIM)][Br] had a decomposition rate greater than that of the dicationic analogue, and the thermodynamic parameters of activation data corroborate these results. Finally, the dicationic ILs did not indicate toxic effects (LD50 > 40 mM).

11.
ACS Omega ; 3(2): 2282-2291, 2018 Feb 28.
Article in English | MEDLINE | ID: mdl-31458529

ABSTRACT

Extensive investigation of interactions and aggregation properties of IL + API systems is necessary to apply ionic liquids (ILs) with different hydrophobic characteristics to drug delivery or in active pharmaceutical ingredient (API) formulations. Therefore, this study aims to investigate the heteroassembly between dicationic ILs ([BisOct(MIM)2][2X], in which X is Br or BF4, and [BisOct(BnIM)2][2Br]), both in the absence and the presence of neutral APIs (salicylic acid, ibuprofen, and paracetamol) with different functional groups. Isothermal titration calorimetry results demonstrate that IL-API associations occur at very low concentrations of IL. These results were reinforced by electrospray ionization mass spectrometry with variable collision-induced dissociation, in which the IL dication interactions with APIs were detected. The strength of the dication-API interaction was determined from E cm,1/2 data. The aggregation parameters (cac, ΔG agg °, and K) between ILs and APIs were evaluated by conductivity. The 1H NMR data showed that differences in chemical shifts provided relevant insights about interaction sites in both components.

12.
ACS Omega ; 3(3): 2569-2578, 2018 Mar 31.
Article in English | MEDLINE | ID: mdl-31458545

ABSTRACT

The quest for concepts of isostructurality in organic crystals has been long and mostly based on geometric data, even with the development of modern software. This field of study is of great interest to the pharmaceutical industry and for the prediction of crystal structures. Despite this, there is still no methodology that provides broad quantitative and comparable similarity data between two complete crystalline structures. The present study demonstrated that the similarity between two crystalline structures could be estimated from the similarity between the two "supramolecular clusters". Quantitative indexes for similarity comparisons of crystal structures were shown using nine 5-aryl-1-(1,1-dimethylethyl)-1H-pyrazoles as a model. This proposal includes the quantitative data of a geometric parameter (I D), a contact area parameter (I C), and an energetic parameter (I G). The proposed indexes exhibited good perspective regarding the similarity data and distinct regions of similarity. The range of similarity was set at I X ≥ 0.80, 0.80 > I X > 0.60, and I X ≤ 0.60 (X = D, C, or G). Indexes with a value near 1.0 indicate systems with isostructural, isocontact, and isoenergetic behavior. The results indicated that supramolecular structures with high similarity must have high values for all three indexes (I D, I C, and I G).

13.
Beilstein J Org Chem ; 13: 2396-2407, 2017.
Article in English | MEDLINE | ID: mdl-29181120

ABSTRACT

An efficient synthesis methodology for a series of tetrazolo[1,5-a]pyrimidines substituted at the 5- and 7-positions from the cyclocondensation reaction [CCC + NCN] was developed. The NCN corresponds to 5-aminotetrazole and CCC to ß-enaminone. Two distinct products were observed in accordance with the ß-enaminone substituent. When observed in solution, the compounds can be divided into two groups: (a) precursor compounds with R = CF3 or CCl3, which leads to tetrazolo[1,5-a]pyrimidines in high regioselectivity with R at the 7-position of the heterocyclic ring; and (b) precursor compounds with R = aryl or methyl, which leads to a mixture of compounds, tetrazolo[1,5-a] pyrimidines (R in the 5-position of the ring) and 2-azidopyrimidines (R in the 4-position of the ring), which was attributed to an equilibrium of azide-tetrazole. In the solid state, all compounds were found as 2-azidopyrimidines. The regiochemistry of the reaction and the stability of the products are discussed on the basis of the data obtained by density functional theory (DFT) for energetic and molecular orbital (MO) calculations.

14.
J Phys Chem B ; 121(35): 8385-8398, 2017 09 07.
Article in English | MEDLINE | ID: mdl-28787160

ABSTRACT

Alkylimidazolium salts are an important class of ionic liquids (ILs) due to their self-assembly capacity when in solution and due to their potential applications in chemistry and materials science. Therefore, detailed knowledge of the physicochemical properties of this class of ILs and their mixtures with natural polymers is highly desired. This work describes the interactions between a homologous series of mono- (CnMIMBr) and dicationic imidazolium (Cn(MIM)2Br2) ILs with cellulose ethers in aqueous medium. The effects of the alkyl chain length (n = 10, 12, 14, and 16), type, and concentration range of ILs (below and above their cmc) on the binding to methylcellulose (MC) were evaluated. The thermodynamic parameters showed that the interactions are favored by the increase of the IL hydrocarbon chain length, and that the binding of monocationic ILs to MC is driven by entropy. The monocationic ILs bind more effectively on the methoxyl group of MC when compared to dicationic ILs, and this outcome may be rationalized by considering the structural difference between the conventional (CnMIMBr) and the bolaform (Cn(MIM)2Br2) surfactant ILs. The C16MIMBr interacts more strongly with hydroxypropylcellulose when compared to methylcellulose, indicating that the strength of the interaction also depends on the hydrophobicity of the cellulose ethers. Our findings highlight that several parameters should be taken into account when designing new complex formulations.


Subject(s)
Imidazoles/chemistry , Ionic Liquids/chemistry , Methylcellulose/chemistry , Surface-Active Agents/chemistry , Binding Sites , Calorimetry , Cations/chemical synthesis , Cations/chemistry , Electric Conductivity , Imidazoles/chemical synthesis , Ionic Liquids/chemical synthesis , Surface Tension , Surface-Active Agents/chemical synthesis , Thermodynamics
15.
Beilstein J Org Chem ; 13: 257-266, 2017.
Article in English | MEDLINE | ID: mdl-28326135

ABSTRACT

The syntheses of several polyazaheterocycles are demonstrated. The cyclocondensation reactions between ß-enaminodiketones [CCl3C(O)C(=CNMe2)C(O)-CO2Et] and aromatic amidines resulted in glyoxalate-substituted pyrido[1,2-a]pyrimidinone, thiazolo[3,2-a]pyrimidinone and pyrimido[1,2-a]benzimidazole. Pyrazinones and quinoxalinones were obtained through the reaction of these glyoxalates with ethylenediamine and 1,2-phenylenediamine derivatives. On the other hand, the reaction of glyoxalates with amidines did not lead to the formation of imidazolones, but rather N-acylated products were obtained. All the products were isolated in good yields. DFT-B3LYP calculations provided HOMO/LUMO coefficients, charge densities, and the stability energies of the intermediates, and from these data it was possible to explain the regiochemistry of the products obtained. Additionally, the data were a useful tool for elucidating the reaction mechanisms.

16.
PLoS One ; 11(4): e0154462, 2016.
Article in English | MEDLINE | ID: mdl-27123587

ABSTRACT

OBJECTIVE: Previous research has yielded evidence of increased attentional processing of negatively valenced body parts in women with anorexia nervosa (AN), especially for those with high depressive symptomatology. The present study extended previous research by implementing an experimental mood manipulation. METHOD: In a within-subjects design, female adolescents with AN (n = 12) and an age matched female control group (CG; n = 12) were given a negative and a positive mood induction at a one-week interval. After each mood induction, participants underwent a 3-min mirror exposure, while their eye movements were recorded. RESULTS: After the positive mood induction, both AN and CG participants displayed longer and more frequent gazes towards their self-defined most ugly relative to their self-defined most beautiful body part. However, after the negative mood induction, only females with AN were characterized by increased attention to their most ugly compared to their most beautiful body part, while CG participants' attention distribution was balanced. Furthermore, in the negative (but not in the positive) mood induction condition gaze frequency and duration towards the most ugly body part was significantly stronger in the AN group relative to the CG. DISCUSSION: The results emphasize the role of negative mood in the maintenance of pathological information processing of the self-body. This increased body-related negativity-bias during negative mood may lead to the persistence and aggravation of AN patients' body image disturbance.


Subject(s)
Affect , Anorexia Nervosa/psychology , Attentional Bias , Body Image/psychology , Depression/psychology , Pessimism/psychology , Adolescent , Anorexia Nervosa/physiopathology , Case-Control Studies , Depression/physiopathology , Eye Movements , Female , Humans , Video Recording
17.
PLoS One ; 10(12): e0145886, 2015.
Article in English | MEDLINE | ID: mdl-26714279

ABSTRACT

OBJECTIVE: Cognitive theories suggest that body dissatisfaction results from the activation of maladaptive appearance schemata, which guide mental processes such as selective attention to shape and weight-related information. In line with this, the present study hypothesized that patients with anorexia nervosa (AN) and bulimia nervosa (BN) are characterized by increased visual attention for the most dissatisfying/ugly body part compared to their most satisfying/beautiful body part, while a more balanced viewing pattern was expected for controls without eating disorders (CG). METHOD: Eye movements were recorded in a group of patients with AN (n = 16), BN (n = 16) and a CG (n = 16) in an ecologically valid setting, i.e., during a 3-min mirror exposure. RESULTS: Evidence was found that patients with AN and BN display longer and more frequent gazes towards the most dissatisfying relative to the most satisfying and towards their most ugly compared to their most beautiful body parts, whereas the CG showed a more balanced gaze pattern. DISCUSSION: The results converge with theoretical models that emphasize the role of information processing in the maintenance of body dissatisfaction. Given the etiological importance of body dissatisfaction in the development of eating disorders, future studies should focus on the modification of the reported patterns.


Subject(s)
Anorexia Nervosa/physiopathology , Anorexia Nervosa/psychology , Attention , Bulimia Nervosa/physiopathology , Bulimia Nervosa/psychology , Visual Perception , Affect , Body Image , Esthetics/psychology , Eye Movements , Female , Humans , Personal Satisfaction , Self Report , Young Adult
18.
Psychiatry Res ; 220(1-2): 490-5, 2014 Dec 15.
Article in English | MEDLINE | ID: mdl-25219613

ABSTRACT

Shame is related to several mental disorders. We assume that facets of shame, namely bodily, cognitive and existential shame, may occur in typical patterns in mental and personality disorders. An excessive level of shame may lead to psychopathological symptoms. However, a lack of shame may also lead to distress, for instance as it may facilitate violation of social norms and thus may promote interpersonal problems. In this study we investigated facets of shame in females suffering from various mental disorders and personality disorders presumably associated with specific aspects of shame. Women suffering from borderline personality disorder (BPD, n=92), attention deficit hyperactivity disorder (ADHD, n=86), major depressive disorder (MDD, n=17), social anxiety disorder (SAD, n=33), and a community sample (COM, n=290) completed the SHAME questionnaire, which is a newly developed instrument to assess adaptive and maladaptive aspects of shame. BPD patients reported the highest level of existential shame compared to all other groups. Compared to the controls, SAD patients displayed stronger bodily and cognitive shame, and ADHD showed lower bodily shame. As assumed, specific aspects of shame were found in different patient groups. It may be important to specifically address these specific aspects of shame in psychotherapy.


Subject(s)
Mental Disorders/diagnosis , Mental Disorders/psychology , Shame , Adult , Attention Deficit Disorder with Hyperactivity/diagnosis , Attention Deficit Disorder with Hyperactivity/psychology , Borderline Personality Disorder/diagnosis , Borderline Personality Disorder/psychology , Depressive Disorder, Major , Female , Humans , Middle Aged , Personality Disorders/diagnosis , Personality Disorders/psychology , Phobic Disorders/diagnosis , Phobic Disorders/psychology , Surveys and Questionnaires , Young Adult
19.
ACS Appl Mater Interfaces ; 6(14): 11536-43, 2014 Jul 23.
Article in English | MEDLINE | ID: mdl-24933673

ABSTRACT

Coated TiO2 nanoparticles by dicationic imidazolium-based ionic liquids (ILs) were prepared and studied by differential scanning calorimetry (DSC), dynamic light scattering (DLS), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), and scanning electron microscopy (SEM). Three ILs with different hydrophobicity degrees and structural characteristics were used (IL-1, IL-2, and IL-3). The interaction between IL molecules and the TiO2 surface was analyzed in both solid state and in solution. The physical and chemical properties of coated nanoparticles (TiO2 + IL-1, TiO2 + IL-2, and TiO2 + IL-3) were compared to pure materials (TiO2, IL-1, IL-2, and IL-3) in order to evaluate the interaction between both components. Thermal behavior, diffraction pattern, and morphologic characteristics were evaluated in the solid state. It was observed that all mixtures (TiO2 + IL) showed different behavior from that detected for pure substances, which is an evidence of film formation. DLS experiments were conducted to determine film thickness on the TiO2 surface comparing the size (hydrodynamic radius, Rh) of pure TiO2 with coated nanoparticles (TiO2 + IL). Results showed the thickness of the film increased with hydrophobicity of the IL compound. TEM images support this observation. Finally, X-ray diffraction patterns showed that, in coated samples, no structural changes in TiO2 diffraction peaks were observed, which is related to the maintenance of the crystalline structure. On the contrary, ILs showed different diffraction patterns, which confirms the hypothesis of interactions happening between IL and the TiO2 nanoparticles surface.

20.
Int J Prev Med ; 5(1): 52-60, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24554992

ABSTRACT

BACKGROUND: Internalizing and externalizing disorders in children and adolescents have been described in many countries. This study was performed to better understand the effect of culture on emotion regulation, and aimed to identify the relationship between emotion regulation and psychopathology in children. METHODS: Participants were 269 children from Iran and Germany who voluntarily agreed to participate. Groups were defined by cultural background, Participants completed the Children Emotion Management Scale (CEMS), Cognitive Emotion Regulation Questionnaire (CERQ), and the Youth self-report YSF questionnaires. Data were analyzed using Multivariate Analysis of Variance (MANOVA) with post-hoc Scheffe tests conducted to identify the exact nature of group differences. RESULTS: There were significant main effect of country (P < 0.001) and sex (P = 0.003). For CEMS, but no significant interaction For CERQ there was a significant main effect of country (P <0.001), but no main effect of sex nor an interaction. MANOVA analyses for internalizing and externalizing symptoms as measured by the YSR indicated significant main effects of country and sex, but the interaction did not reach significance (P=0.088). CONCLUSIONS: A main result of the study showed that children in Iran report more internalizing and externalizing symptoms. Culture and emotional expression may explain differences between Iranian and German children. It seems to be difficult for young children in Iran to express themselves, this may be because they are expected to show respect to maintain harmony in the family.

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