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1.
Int J Psychiatry Med ; 59(2): 232-247, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37503904

RESUMO

OBJECTIVE: Various factors may influence the attitudes of medical students towards euthanasia, including personal values, beliefs, and personality traits. The objective of this study was to examine the attitudes of 2nd and 5th year medical students about euthanasia and the relationship between these attitudes and students' personality traits. METHODS: Medical students from the Universities of Kragujevac and Belgrade, Serbia, participated in this study. A questionnaire was administered assessing attitudes toward euthanasia and student personality traits (honesty-humility, emotionality, extraversion, agreeableness, conscientiousness, and openness using the HEXACO-60). RESULTS: More than 50% of students in the second year and 60% of students in the fifth year were supportive of euthanasia. Students in the 5th year were 2.5 times more likely to express a concern that euthanasia needs to be clearly regulated by law compared to students in the second year. Adjusted analyses indicated that lower levels of honesty-humility and emotionality were positively correlated with students' belief that euthanasia should be legalized. CONCLUSION: Many medical students in Serbia have a positive attitude towards euthanasia. It is important to consider the possible influences of culture, religion, and the law on attitudes towards euthanasia. Undergraduate medical training should include more hours dedicated to palliative care and end-of-life topics to raise awareness of patients' preferences in this regard.


Assuntos
Eutanásia , Estudantes de Medicina , Humanos , Sérvia , Personalidade , Atitude , Inquéritos e Questionários
2.
Am J Dent ; 37(1): 9-12, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458976

RESUMO

PURPOSE: To evaluate the influence of group and individual education on shade matching quality using a visual color competency test to match shade tab pairs from two Vita classical A1-D4 shade guides. METHODS: 60 dental students, 21-25 years old (39 females, 21 males) participated in the study. All participants passed a color deficiency test before the experiment. The examination was voluntary and approved by the corresponding Ethics Committee. Students were randomly divided into three groups (n=20): one control group, NE (no education) and two experimental groups - GE (group education) and IE (individual education). The study was performed in three phases. In the "before" (B - Phase 1) and "after" (A - Phase 3) phase, all groups had to match 16 pairs of tabs from two Vita classical A1-D4 shade guides, with the shade designations hidden by custom letter markings. All tabs were mixed on a gray surface illuminated by color-correcting light. In Phase 2 (between B and A), GE had only group education, while IE received additional individual education and training. The control group did not participate in Phase 2. Means and standard deviations were calculated, and differences were compared using the one-way ANOVA, ANCOVA test, and Student t-test for dependent samples (α= 0.05). RESULTS: The NE group matched 10.3 (3.2) and 10.4 (2.9) tab pairs in the before and after phases, respectively. Corresponding results for GE were 11.1 (2.2) and 14.4 (1.9) and 9.5 (3.6) and 15.0 (1.5) for IE, respectively. In Phase 1 (B), no statistically significant difference was recorded among the groups (P= 0.260). The experimental groups achieved a statistically significant improvement compared with the control group in Phase 3 (A) (P< 0.001). Both experimental groups achieved statistically significant improvement within the group after education, GE (P< 0.001) and IE (P< 0.001). Within the limitations of this study, it was concluded that both experimental groups had statistically significant progress in shade matching. The group that received individual education (IE) made statistically significant progress compared with the group that received group education (GE). No statistically significant difference was found in the results of the control group between Phase 1 and Phase 3 of the study. CLINICAL SIGNIFICANCE: Improving the shade matching ability facilitates the work of dentists and dental technicians and enhances the esthetics of dental restorations.


Assuntos
Percepção de Cores , Estudantes de Odontologia , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Cor , Planejamento de Prótese Dentária , Pigmentação em Prótese
3.
J Esthet Restor Dent ; 36(1): 116-123, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37086204

RESUMO

OBJECTIVES: To evaluate the influence of the group and individual education of students on shade matching quality. Secondary study objective included a survey-assessment of quality and difficulty level of color matching. MATERIALS AND METHODS: Forty dental student participants in Integrated Academic Studies of Dentistry at the Faculty of Medicine, University of Nis (26 female, 14 male) 21-25 years old, signed consent to voluntarily participate in the research. The Ethics Committee of the Clinic of Dentistry, Faculty of Medicine, University of Nis, approved the study under number 14/11-2019-2EO. They were randomly divided into two groups (n = 20), experimental (IE, individual education) and control (GE, group education). Each group was divided into four subgroups (n = 5). The study was performed in three phases. In Phase I (I) and III (III), students matched the shade of the maxillary central left incisor (#9) using three different shade guides. Each of the students served as a "patient" for shade matching, while the other members of the subgroup, individually (VMI ) and as a team (VMT ), visually matched the tooth shade. In Phase II (between phases I and III), group IE received standard group and individual education and training, while group GE had only group education. Shade matching results in before and after education were compared with results obtained by an intraoral spectrophotometer. CIELAB (∆E*), and CIDE2000 color differences (∆E00 ) were calculated. The color differences between VMI or VMT and ES readings were graded. In addition, the students rated the level of difficulty and quality of shade matching from 1 to 5, signifying the most to least difficult, and the worst to best match, respectively. Means and standard deviations were calculated. Differences were compared using the Student t-test. RESULTS: Means (s.d.) of CIEDE2000 color differences for VMI before and after IE were 4.5 (1.5) and 3.3 (0.9), respectively. Corresponding values for group GE were 4.4 (1.4) and 4.0 (1.0), respectively. As compared with GE, group IE achieved 15% better results for the best matches and 27.5% for one of the three best matches in by-point comparison. Mean (s.d.) results for VMT in the experimental group before and after IE were 3.6 (2.4) and 2.8 (1.6), respectively. Corresponding results for the control group were 4.4 (2.1) and 3.5 (1.7), respectively. Group IE had statistically higher VMI and VMT scores than GE, while, for GE, only VMT scores were statistically higher. Group IE achieved better results in by-point comparison. After education and training, the students rated the shade matching as more precise and less difficult. Results were significantly better for Quality (IE) (sig = 0.010) and Difficulty (GE) (sig = 0.021). CONCLUSIONS: Within the limitations of the study, the experimental group achieved significantly better results in individual color matching after education and training than the control group, while both groups made progress in team color matching. Both groups rated shade matching more accurate and easier after education. CLINICAL SIGNIFICANCE: Improving the quality of shade matching is expected to enhance the esthetics of dental restorations, increase patient satisfaction, and reduce color corrections.


Assuntos
Percepção de Cores , Planejamento de Prótese Dentária , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Cor , Pigmentação em Prótese , Espectrofotometria , Estudantes de Odontologia
4.
J Pers ; 91(6): 1381-1394, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36660808

RESUMO

OBJECTIVE: Disintegration is a recently proposed broad, trait-like reconceptualization of the proneness to psychotic-like experiences/behaviors. METHODS: We tested the assumption that the 6-factor model (Five-Factor traits plus Disintegration) was the most adequate one and that it was invariant across clinical and non-clinical populations. The clinical sample (n = 161) consisted of patients who had at least one psychotic episode, duration of illness less than 10 years, currently in remission. The general population (n = 409) was matched with the patient sample by age, gender, and education. NEO PI-R and DELTA were used to measure personality dimensions in both samples. Invariance of one to six-factor solutions was tested by Exploratory Structural Equation Modeling. RESULTS: We found that: (a) several criteria for deciding on the number of factors to retain converged to the conclusion that the assumed 6-factor model was the most adequate one, (b) the assumed factorial structure appeared to satisfy the criteria for the scalar invariance across the two samples, (c) all nine Disintegration subdimensions separated from the Big Five, forming the Disintegration factor, and (d) Disintegration was unrelated to Openness. CONCLUSION: The Big Five personality structure-complemented with disintegration-was invariant across individuals from the general population and patients with psychosis.


Assuntos
Personalidade , Transtornos Psicóticos , Humanos , Transtornos da Personalidade , Inventário de Personalidade
5.
J ECT ; 38(4): 230-237, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35462388

RESUMO

OBJECTIVES: Pre-electroconvulsive therapy (ECT) evaluation is an essential part of ECT preparation, a standard treatment in the psychiatric field. However, no routine pre-ECT evaluation has been published so far. This preliminary study aimed to explore different practices in pre-ECT evaluation across European countries. METHODS: The data were collected as a snowball sample approach using an online survey from September 2019 to April 2020. The final analysis included data from 18 clinics placed in 16 European countries. RESULTS: Regulations on the pre-ECT evaluation were found in 9 countries. All clinics reported doing complete blood count, serum electrolytes, and renal function analysis as a part of regular laboratory testing, alongside with a cardiovascular assessment. Ten clinics reported using psychiatric scales. Six clinics reported doing a cognitive assessment, of which all had regulations on the pre-ECT evaluation. Not one evaluation had the same sets of procedures and diagnostics. CONCLUSIONS: The differences in assessment approaches mirror high variability of the pre-ECT evaluation practice across Europe. Cognitive assessment and objectification of psychiatric symptoms should be a regular part of the pre-ECT evaluation because of the monitoring of the most common adverse effect and observing the clinical response to ECT. Standardization of the pre-ECT evaluation and ECT in general would remove criticisms and opposition to the treatment, make it based on the best of our knowledge, and provide a method respectful of patients' best interests and rights.


Assuntos
Eletroconvulsoterapia , Transtornos Mentais , Humanos , Eletroconvulsoterapia/métodos , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia , Transtornos Mentais/psicologia , Inquéritos e Questionários , Europa (Continente)
6.
Int J Mol Sci ; 23(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35055172

RESUMO

Reduced graphene oxide (rGO) is one of the graphene derivatives that can be employed to engineer bioactive and/or electroactive scaffolds. However, the influence of its low and especially high concentrations on scaffolds' overall properties and cytotoxicity has yet to be explored. In this study, polyethylene oxide (PEO)-based scaffolds containing from 0.1 to 20 wt% rGO were obtained by electrospinning. Morphological, thermal and electrical properties of the scaffolds were characterized by SEM, Raman spectroscopy, XRD, DSC and electrical measurements. The diameter of the fibers decreased from 0.52 to 0.19 µm as the concentration of rGO increased from 0.1 wt% to 20 wt%. The presence of rGO above the percolation threshold (5.7 wt%) resulted in a significantly reduced electrical resistivity of the scaffolds. XRD and Raman analysis revealed delamination of the graphene layers (interlayer spacing increased from 0.36 nm to 0.40-0.41 nm), and exfoliation of rGO was detected for the samples with an rGO concentration lower than 1 wt%. In addition, an evident trend of increasing cell viability as a function of the rGO concentration was evidenced. The obtained results can serve as further guidance for the judicious selection of the rGO content incorporated into the PEO matrix for constructing electroactive scaffolds.


Assuntos
Grafite/química , Polietilenoglicóis/química , Alicerces Teciduais/química , Linhagem Celular , Sobrevivência Celular , Humanos , Análise Espectral Raman , Engenharia Tecidual , Difração de Raios X
7.
BMC Psychiatry ; 21(1): 468, 2021 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-34563145

RESUMO

BACKGROUND: Implementation of psychosocial interventions in mental health services has the potential to improve the treatment of psychosis spectrum disorders (PSD) in low- and middle-income countries (LMICs) where care is predominantly focused on pharmacotherapy. The first step is to understand the views of key stakeholders. We conducted a multi-language qualitative study to explore the contextual barriers and facilitators to implementation of a cost-effective, digital psychosocial intervention, called DIALOG+, for treating PSD. DIALOG+ builds on existing clinician-patient relationships without requiring development of new services, making it well-fitting for healthcare systems with scarce resources. METHODS: Thirty-two focus groups were conducted with 174 participants (patients, clinicians, policymakers and carers), who were familiarized with DIALOG+ through a presentation. The Southeast European LMICs included in this research were: Bosnia and Herzegovina, Kosovo, (Kosovo is referred throughout the text by United Nations resolution) North Macedonia, Montenegro and Serbia. Framework analysis was used to analyse the participants' accounts. RESULTS: Six major themes were identified. Three themes (Intervention characteristics; Carers' involvement; Patient and organisational benefits) were interpreted as perceived implementation facilitators. The theme Attitudes and perceived preparedness of potential adopters comprised of subthemes that were interpreted as both perceived implementation facilitators and barriers. Two other themes (Frequency of intervention delivery; Suggested changes to the intervention) were more broadly related to the intervention's implementation. Participants were exceedingly supportive of the implementation of a digital psychosocial intervention such as DIALOG+. Attractive intervention characteristics, efficient use of scarce resources for its implementation and potential to improve mental health services were seen as the main implementation facilitators. The major implementation barrier identified was psychiatrists' time constrains. CONCLUSIONS: This study provided important insights regarding implementation of digital psychosocial interventions for people with PSD in low-resource settings by including perspectives from four stakeholder groups in five LMICs in Southeast Europe - a population and region rarely explored in the literature. The perceived limited availability of psychiatrists could be potentially resolved by increased inclusion of other mental health professionals in service delivery for PSD. These findings will be used to inform the implementation strategy of DIALOG+ across the participating countries. The study also offers insights into multi-country qualitative research.


Assuntos
Saúde Mental , Transtornos Psicóticos , Atenção à Saúde , Pessoal de Saúde , Humanos , Transtornos Psicóticos/terapia , Pesquisa Qualitativa
8.
Int J Psychiatry Clin Pract ; 24(3): 315-321, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32459564

RESUMO

Introduction: Prescribing trends in maintenance therapy of patients with primary psychotic disorders (PSD) may vary worldwide. Present study aimed to investigate prescription patterns in a sample of outpatients with PSD from Serbia.Methods: In a sample of 73 PSD outpatients we analysed the rate of antipsychotic polypharmacy and psychotropic polypharmacy, concomitant continual benzodiazepine use, and associations between therapy, psychotic symptoms and quality of life.Results: Maintenance therapy (median daily dose 321 mg of chlorpromazine equivalents) predominantly consisted of monotherapy with second generation antipsychotics (45.2%), followed by antipsychotic polypharmacy based on first and second generation combination (25.0%). The median number of psychotropic drugs was 3. Benzodiazepines were continually prescribed to more than 60% of patients (mean daily dose 2.9 ± 2.0 mg lorazepam equivalents). Patients with benzodiazepine use had significantly more psychotropic medications and more antipsychotic polypharmacy, poorer quality of life and more severe psychopathology in comparison to another group.Conclusion: The present study demonstrated new information regarding the prescription patterns of psychotropic drugs in outpatients with PSD in Serbia, amplified with clinically relevant information. This study also revealed distinct prescription patterns concerning antipsychotic/benzodiazepine polypharmacy. Overall, such findings are likely to contribute to improving clinical practice and care for patients with PSD in general.KeypointsPresent exploratory research aimed to elucidate trends of antipsychotics polypharmacy and concomitant use of psychotropic medications including benzodiazepines in the maintenance treatment of outpatients with schizophrenia and other psychotic disorders, amplified with clinically relevant information (symptoms and quality of life).'Antipsychotic (AP) polypharmacy' was defined as concurrent use of more than one AP for at least 1 month; 'Psychotropic polypharmacy' was defined as the combination of AP and a different class of psychotropic drugs medication for at least one month.The median number of prescribed psychotropic drugs was 3 (mean 3.1 ± 1.1) and the average AP daily dose was moderate (median 321 mg of chlorpromazine equivalents). However, the rates of AP polypharmacy (45.2%) and benzodiazepine prescription on a continual basis (>60%) found in our sample could be considered relatively high.Outpatients with higher AP daily dose and higher BPRS symptom score were receiving more benzodiazepines.For improvement of the local, as well as general clinical practice and care for patients with psychotic disorders, and for education in psychiatry, such analyses need to be done on a regular basis and on larger samples.


Assuntos
Antipsicóticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Pacientes Ambulatoriais/estatística & dados numéricos , Polimedicação , Padrões de Prática Médica/estatística & dados numéricos , Transtornos Psicóticos/tratamento farmacológico , Esquizofrenia/tratamento farmacológico , Prevenção Secundária/estatística & dados numéricos , Adulto , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Sérvia , Índice de Gravidade de Doença , Fatores de Tempo
9.
Med Sci Monit ; 25: 3397-3405, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31066356

RESUMO

BACKGROUND While several tests can be used in the laboratory evaluation of composite resin-based cement materials, the push-out test remains the most prevalent. Due to difficulties in sample preparation, as well as a highly complex procedure, we attempted to develop an alternative method for testing the bond strength of dental resin cement materials. MATERIAL AND METHODS Ninety-six experimental samples of 2 dual-cure resin cements and 1 fiber post system were prepared for the 2 testing procedures: the push-out test and the modified Microbond test. The degree of monomer conversion was measured by Fourier-transform infrared spectroscopy. RESULTS The push-out test results indicated that the bond strength of dual-cure resin cement differs depending on the tooth root region to which it is applied (p<0.05), In addition, our findings show that Variolink II exhibits a much lower bond strength relative to RelyX ARC. These findings were confirmed by the modified Microbond test results. The monomer conversion rate results indicate average conversion rates of 85.81% and 61.35% for RelyX ARC and Variolnik II, respectively. CONCLUSIONS Our study confirms the practical utility of the modified Microbond test in the assessment of bond strength of dental cement resin-based materials. The proposed test method is particularly useful given that, relative to the push-out test, it requires a much smaller number of preparation and execution steps, thus reducing the potential for introducing errors, while increasing the reliability of the obtained findings.


Assuntos
Colagem Dentária/métodos , Cimentos Dentários/química , Cimentos de Resina/química , Adesivos , Bis-Fenol A-Glicidil Metacrilato , Resinas Compostas/química , Materiais Dentários/química , Porcelana Dentária , Cavidade Pulpar , Análise do Estresse Dentário , Dentina , Humanos , Teste de Materiais , Polietilenoglicóis , Ácidos Polimetacrílicos , Reprodutibilidade dos Testes , Resinas Sintéticas/química , Raiz Dentária
10.
Cogn Neuropsychiatry ; 24(2): 108-122, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30789053

RESUMO

BACKGROUND: Previous studies examining sex-differences in facial emotion recognition (FER) in psychosis yielded inconsistent results. Although females are considered to be superior in FER in health, it remains unclear whether the specific sex-difference is present in psychosis. We aimed to examine whether women and men differ in FER ability in health and in psychosis, and to explore potential sex differences in the illness' effects on FER. METHODS: Remitted psychotic patients and controls were assessed using the CANTAB Emotion Recognition Task (ERT) examining accuracies/response latencies in identifying basic emotional expressions. General linear model was performed to assess the effects of group, sex and their interactions on ERT performance. RESULTS: Healthy females showed FER advantage in comparison to healthy males, while the aforementioned sex-difference was not observed in remitted psychotic patients. Our results also demonstrated the existence of overall FER deficit in psychosis in comparison to healthy controls, as well as the differential illness' effects on the recognition accuracy of facial expression of anger in males and females-suggesting that females with psychotic disorders undergo more profound deterioration of FER ability than their male counterparts. CONCLUSION: The assessment of sex-differences in FER and other important features of psychosis is important for better understanding of its neurobiological basis and for the development of targeted treatments for improved functioning.


Assuntos
Emoções/fisiologia , Reconhecimento Facial/fisiologia , Testes Neuropsicológicos , Transtornos Psicóticos/psicologia , Reconhecimento Psicológico/fisiologia , Caracteres Sexuais , Adulto , Expressão Facial , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/diagnóstico , Adulto Jovem
11.
J Esthet Restor Dent ; 28(5): 287-294, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27061853

RESUMO

OBJECTIVES: To evaluate the influence of education and training on quality of tooth color matching. MATERIAL AND METHODS: Dental students (N = 174), matched the color of eight shade tabs in a viewing booth, using VITA Linearguide 3D-Master shade guide. The experimental group had color education and training between the before and after session. The control group did not have any additional information in between two sessions. Color differences between the task tabs and selected tabs were calculated using CIE formulas. The score for the best match (smallest color difference) was 10 points, the 2nd best match 9 points, down to 1 point for the 10th best match. Means and standard deviations were calculated. Differences were analyzed using the Student t-test. RESULTS: Shade matching scores in the experimental group were significantly better after education and training (p < 0.001), with a mean score before and after shade matching sessions of 7.06 (1.19) and 8.43 (0.92), respectively. The percentage of students in the experimental group that selected one of three best matches increased 24.3%. The control group exhibited no significant improvement in the after session. CONCLUSIONS: Within the limitations of the study, education and training improved students' shade matching skills. CLINICAL SIGNIFICANCE: While the vast majority of dental restorations and practically all restorations in the esthetic zone are tooth colored, the profession as a whole is far from perfect when it comes to accurate shade matching. Education and training can improve shade matching ability: enhanced esthetics of dental restorations, increased patient satisfaction, and a reduced number of color corrections are some of the notable benefits and rewards. (J Esthet Restor Dent 00:000-000, 2016) J Esthet Restor Dent 28:287-294, 2016).


Assuntos
Percepção de Cores , Planejamento de Prótese Dentária , Pigmentação em Prótese , Estudantes de Odontologia , Cor , Humanos
13.
Int J Pharm ; 649: 123634, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38000651

RESUMO

Supercritical fluid technology (SFT) is an insufficiently investigated approach for the production of solid dispersions, it is environmentally acceptable and has a high potential for application in the pharmaceutical industry. The aim of this work was to formulate and characterize nifedipine solid dispersions (SDs) produced by the SFT and compare the results with ones obtained by the classical solvent based kneading method. The following in vitro tests were conducted: assay and yield, solvent residues, solid state characterization (FTIR, DSC, XRD), flowability, hygroscopicity, solubility, dissolution and stability. Additionally, bioavailability was examined on an animal model (Wistar rats). The formulation selection for in vivo study was performed using the multilevel categoric experimental design and the health risk assessment. Solid state characterization revealed that formulation obtained by the SFT method and higher ratio of polymer (1:5) have had nifedipine in completely amorphous form. Polymer ratio and method of SDs preparation do influence the investigation characteristics. Dissolution rate was fastest in SDs prepared by the SFT and higher polymer ration (1:5). In vivo data of selected SDs prepared by the kneading (ratio 1:1) and the SFT (ratio 1:5) showed alteration in pharmacokinetic profile after i.v. and p.o. application.


Assuntos
Nifedipino , Polímeros , Ratos , Animais , Ratos Wistar , Polímeros/química , Solubilidade , Solventes/química , Disponibilidade Biológica , Tecnologia , Varredura Diferencial de Calorimetria
14.
Polymers (Basel) ; 15(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37765608

RESUMO

A series of polyurethanes (PU) were synthesised via one-step polymerisation without a chain extender, using toluene diisocyanate as well as a variety of soft segments composed of different macrodiols. Poly(D,L-lactide) (PDLLA) and polycaprolactone diol (PCL) were synthesised as a polyester type polyols to obtain soft segments. The process of varying the molar ratio of newly synthesised PDLLA in soft segments has been confirmed as a powerful tool for fine-tuning the final properties of PU. Fourier-transformed infrared spectroscopy was used for evaluation of molecular structures of synthesised PDLLA polyol and final PU. Nuclear magnetic resonance spectrometry was used to confirm the presumed structure of PU. The influence of soft segment composition on polyurethane thermal characteristics was examined using thermogravimetric analysis and differential scanning calorimetry. The composition of soft segments had little impact on the thermal stability of PU materials, which is explained by the comparable structures of both polyester polyols. Wide-angle X-ray scattering was utilised to evaluate the effect of amorphous PDLLA on the degree of crystallinity of PCL in soft PU segments. It was discovered that not only did the PDLLA ratio in the soft segment have a substantial influence on the degree of microphase separation in the soft and hard segments, but it also influenced the crystallisation behaviour of the materials. Furthermore, the restriction of crystallisation of the PCL soft segment has been verified to be dependent on the hard segment concentration and the ratio of PDLLA/PCL polyols. The sample with pure PCL as the polyol component achieved the highest degree of crystallinity (34.8%). The results demonstrated that the composition of soft segments directly affected the properties of obtained polyurethane films. These results can be utilised to easily achieve a desirable set of properties required for application in biomaterials.

15.
Nat Prod Res ; : 1-8, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37621206

RESUMO

The past decade has seen increasing interest in plant oils in the food, pharmaceutical, and cosmetic industries due to their diverse functional and nutritional properties, as well as the high levels of consumer acceptance. As a result, there has been a spike in research interest in finding new sources of oils with good potential for industrial use. In this paper, the chemical characterisation (saponification, iodine, acid and ester numbers, as well as fatty acid composition) of nettle seed oil was given. Oil was analysed for its thermooxidative stability by differential scanning calorimetry. The kinetic parameters of oxidation (Ea, A, and k) were also determined. The results showed that nettle seed oil belongs to the group of edible oils of the linoleic type and it is nutritionally highly valuable, it has pronounced thermooxidative stability and could be an alternative source of raw material for the food, cosmetics, and other non-food industries.

16.
Brain Sci ; 13(4)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37190570

RESUMO

The growing body of evidence on the dimensional classification of personality disorders (PD) has resulted in its acceptance in the ICD-11 classification, which abolished categories and retains only a general description of PD. Specifying the type of PD is optional, and the suggested domains represent maladaptive variants of the five-factor model of personality (FFM). The aim of our study was to explore the existence of a joint structure between maladaptive and normal personality traits, and to investigate how these structures are integrated. The study included 223 patients who had been diagnosed with PD and completed the Structured Clinical Interview for DSM-5 Personality Disorders and the NEO Personality Inventory-Revised (NEO-PI-R). To determine the degree of overlap between PD domains and NEO PI-R scales, a canonical analysis of covariance was conducted. Our findings showed a relationship between the internalizing PD spectrum (consisting of avoidant, dependent, and borderline traits with detached and anankastic traits) and high neuroticism, low conscientiousness, and moderately low agreeableness and extroversion, suggesting the existence of a broad personality disorder factor. However, the internalizing dimensions exhibited a more pronounced effect within this construct. Furthermore, we identified a second function that demonstrated a link between the externalizing PD spectrum (including narcissistic, histrionic, and antisocial traits) and high extraversion, high openness, and low agreeableness, suggesting the existence of an externalizing factor. Overall, our findings provide evidence for a joint structure of maladaptive and normal personality traits in a sample of personality disorders and emphasize the importance of integrating the FFM model in PD evaluation in clinical practice, suggesting that differentiating between major subgroups could assist in adjusting therapeutic approaches.

17.
Gels ; 9(1)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36661836

RESUMO

The objectives of this study are the synthesis of thermosensitive poly(N-isopropylacrylamide-co-2-hydroxypropyl methacrylate), p(NiPAm-HPMet), hydrogels and the analysis of a drug-delivery system based on piroxicam, as a model drug, and synthesized hydrogels. A high pressure liquid chromatography method has been used in order to determine both qualitative and quantitative amounts of unreacted monomers and crosslinkers from polymerized hydrogels. Swelling kinetics and the order of a swelling process of the hydrogels have been analyzed at 10 and 40 °C. The copolymers' thermal properties have been monitored by the differential scanning calorimetry (DSC) method. DSC termograms have shown that melting occurs in two temperature intervals (142.36-150.72 °C and 153.14-156.49 °C). A matrix system with incorporated piroxicam has been analyzed by using FTIR and SEM methods. Structural analysis has demonstrated that intermolecular non-covalent interactions have been built between side-groups of copolymer and loaded piroxicam. Morphology of p(NiPAm-HPMet) after drug incorporation indicates the piroxicam presence into the copolymer pores. Kinetic parameters of the piroxicam release from hydrogels at 37 °C and pH 7.4 indicate that the fluid transport mechanism corresponds to Fickian diffusion. As a result, formulation of thermosensitive p(NiPAm-HPMet) hydrogels with incorporated piroxicam could be of interest for further testing as a drug carrier for modulated and prolonged release, especially for topical administration.

18.
Polymers (Basel) ; 15(20)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37896400

RESUMO

As cementation represents the last stage of the work involved in making various indirect restorations (metal ceramic crowns and bridges, full ceramic crowns and bridges, inlays, onlays, and fiber posts), its quality significantly contributes to the clinical success of the therapy performed. In the last two decades, the demand for ceramic indirect restorations in everyday dental practice has considerably increased primarily due to the growing significance of esthetics among patients, but also as a result of hypersensitivity reactions to dental alloys in some individuals. In this context, it is essential to ensure a permanent and reliable adhesive bond between the indirect restoration and the tooth structure, as this is the key to the success of aesthetic restorations. Resin-based luting materials benefit from excellent optical (aesthetic) and mechanical properties, as well as from providing a strong and durable adhesive bond between the restoration and the tooth. For this reason, resin cements are a reliable choice of material for cementing polycrystalline ceramic restorations. The current dental material market offers a wide range of resin cement with diverse and continually advancing properties. In response, we wish to note that the interest in the properties of resin-based cements among clinicians has existed for many years. Yet, despite extensive research on the subject and the resulting continued improvements in the quality of these materials, there is still no ideal resin-based cement on the market. The manuscript authors were guided by this fact when writing the article content, as the aim was to provide a concise overview of the composition, properties, and current trends, as well as some future guidelines for research in this field that would be beneficial for dental practitioners as well as the scientific community. It is extremely important to provide reliable and succinct information and guidelines for resin luting materials for dental dental practitioners.

19.
Gels ; 9(9)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37754365

RESUMO

The purposes of this study are the polymerization of temperature-sensitive copolymers based on N-isopropyl acrylamide and 10 mol % of 2-hydroxypropylmethacrylate, characterisations of their thermal, morphological and swelling properties, as well as the analysis of potential application in drug-delivery systems. Acetaminophen, the representative of non-steroidal anti-inflammatory drugs, was used as a model drug in this study. It is a common pain relief drug, which is also used for fever treatment. However, oral administration comes with certain health risks, mainly the overdose and frequent administration of up to four times a day. The goal of applying temperature-sensitive hydrogel is to enable extended administration once a day, depending on the body temperature. The swelling behavior of the obtained poly(N-isopropyl acrylamide-co-2-hydroxypropylmethacrylate) (p(NIPA/HPMA)) hydrogels and their temperature-sensitivity, kinetics and order of swelling processes at 18 and 38 °C were analyzed. The thermal properties of these hydrogels were observed by the DSC method, and the obtained thermograms showed both melting and glass transitions. The drug delivery system of p(NIPA/HPMA) hydrogels with loaded acetaminophen was analyzed using scanning electron microscopy and Fourier transform infrared spectroscopy methods. Structural analysis of FTIR spectra indicates that non-covalent intermolecular interactions of the type of hydrogen bonds were formed among functional groups of acetaminophen and side-chains of p(NIPA/HPMA) hydrogels. The surface structure of p(NIPA/HPMA) hydrogels after drug loading indicates the acetaminophen presence into the pores of the hydrogel network, and their loading efficiency was higher than 92%. Qualitative and quantitative analysis of acetaminophen, determined by the high-pressure liquid chromatography method, showed that about 90-99% of the loaded amount was released from p(NIPA/HPMA) hydrogels within 24 h. Kinetic parameters of the acetaminophen release under simulated gastrointestinal conditions were determined. Based on obtained results, the drug delivery system of temperature-sensitive p(NIPA/HPMA) hydrogels with loaded acetaminophen could be suitable for additional investigation for modulated drug administration, e.g., for extended drug administration.

20.
Polymers (Basel) ; 15(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37376244

RESUMO

As the mechanical properties of resin-based dental composite materials are highly relevant in clinical practice, diverse strategies for their potential enhancement have been proposed in the extant literature, aiming to facilitate their reliable use in dental medicine. In this context, the focus is primarily given to the mechanical properties with the greatest influence on clinical success, i.e., the longevity of the filling in the patient's mouth and its ability to withstand very strong masticatory forces. Guided by these objectives, the goal of the present study was to ascertain whether the reinforcement of dental composite resins with electrospun polyamide (PA) nanofibers would improve the mechanical strength of dental restoration materials. For this purpose, light-cure dental composite resins were interspersed with one and two layers comprising PA nanofibers in order to investigate the influence of such reinforcement on the mechanical properties of the resulting hybrid resins. One set of the obtained samples was investigated as prepared, while another set was immersed in artificial saliva for 14 days and was subsequently subjected to the same set of analyses, namely Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). Findings yielded by the FTIR analysis confirmed the structure of the produced dental composite resin material. They also provided evidence that, while the presence of PA nanofibers did not influence the curing process, it strengthened the dental composite resin. Moreover, flexural strength measurements revealed that the inclusion of a 16 µm-thick PA nanolayer enabled the dental composite resin to withstand a load of 3.2 MPa. These findings were supported by the SEM results, which further indicated that immersing the resin in saline solution resulted in a more compact composite material structure. Finally, DSC results indicated that as-prepared as well as saline-treated reinforced samples had a lower glass transition temperature (Tg) compared to pure resin. Specifically, while pure resin had a Tg of 61.6 °C, each additional PA nanolayer decreased the Tg by about 2 °C, while the further reduction was obtained when samples were immersed in saline for 14 days. These results show that electrospinning is a facile method for producing different nanofibers that can be incorporated into resin-based dental composite materials to modify their mechanical properties. Moreover, while their inclusion strengthens the resin-based dental composite materials, it does not affect the course and outcome of the polymerization reaction, which is an important factor for their use in clinical practice.

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