Personality traits and attitude towards euthanasia among medical students in Serbia.

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.

Effect of group and individual education on shade matching competency of dental students.

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.

Influence of individual education and training on quality of color matching in dentistry.

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.

Exploring real-world prescribing patterns for maintenance treatment in bipolar disorders: a focus on antidepressants and benzodiazepines.

OBJECTIVE: Bipolar disorders (BD) are characterized by highly recurrent nature, necessitating adequate maintenance treatment for long-term disorder control. This study aimed to investigate real-world prescribing patterns among outpatients with BD, focusing on the utilisation of antidepressants (AD) and benzodiazepines (BDZ). METHODS: We analysed prescription patterns of the five main groups of psychotropic medications (antipsychotics, mood stabilizers, AD, BDZ, and anticholinergic medications) and their relationships with basic socio-demographic and clinical data in a sample of 107 clinically stable BD outpatients (75.7% female, age 44.8 ± 11.7). RESULTS: Maintenance therapy predominantly involved polypharmacy (92.5%), with mood stabilizers (87.9%) and antipsychotics (80.4%, predominantly second-generation) being the most commonly prescribed. Our findings highlight a high percentage of patients prescribed AD (50.5%) and BDZ (54.2%). BDZ patients, compared to the non-BDZ group in maintenance treatment, were significantly older with longer psychiatric history and a decreased likelihood of comorbid personality disorder diagnoses. CONCLUSIONS: This study offers insights into prescribing practices within a university psychiatric clinic in the Western Balkans. The prevalent use of polypharmacy in real-world clinical settings, along with high percentage of patients prescribed AD and BDZ, suggests a gap between guideline recommendations and clinical practice, indicating a lack of consensus or standardized approaches in clinical practice.

Study uncovers prescribing practices in a Western Balkans university psychiatric clinic, revealing high polypharmacy prevalence (92.5%) among clinically stable bipolar disorder (BD) outpatients.Most BD outpatients received mood stabilizers, particularly lamotrigine, and second-generation antipsychotics, notably olanzapine, with a minority on monotherapy.Antidepressant and benzodiazepine usage was notably high despite guidelines favouring monotherapy, reflecting challenges in managing residual morbidity.AD usage in BD type I is discouraged due to risks, while their use in BD type II is considered in certain scenarios, emphasising tailored treatment.High mean daily BDZ dose (approximately 3.5mg lorazepam equivalents) in non-acute outpatient BD maintenance therapy raises concerns about potential long-term implications for patient health and underscores the need for vigilant monitoring of prescribing practices.

Do people diagnosed with psychosis spectrum disorders share the same personality space as the general population? Big Five complemented by the proneness to psychotic-like experiences/behaviors.

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.

Preliminary Assessment of Pre-Electroconvulsive Therapy Evaluation Practices in European Countries: The Need for Guidelines.

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.

Electrospun PEO/rGO Scaffolds: The Influence of the Concentration of rGO on Overall Properties and Cytotoxicity.

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.

Implementing a digital mental health intervention for individuals with psychosis - a multi-country qualitative study.

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.

Maintenance phase treatment of psychotic disorders in outpatients from Serbia - focus on long-term benzodiazepine use.

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.

Application of a Novel Modification of the Microbond Test for Evaluation of Adhesive Bond Strength Between Fiber Posts and Dual-Cure Dental Resin Cement.

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.

Sex differences in facial emotion recognition in health and psychotic disorders.

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.

Influence of Color Education and Training on Shade Matching Skills.

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).

The Influence of Removable Complete Denture on Pro-Oxidant Antioxidant Balance and Redox-Sensitive Inflammation Biomarker NF-ĸB in the Oral Cavity: An Interventional Follow-Up Study.

OBJECTIVES: Oxidative stress, an imbalance between the body's natural antioxidant defenses and the production of reactive oxygen species (ROS), can result in serious oral diseases, including oral cancer, periodontal diseases, and oral lichen planus, through the activation of the redox-sensitive transcription factors and inflammation. The purpose of this study was to assess the potential effects of a removable complete denture on the levels of oxidative stress markers, such as lipid peroxidation (MDA), advanced oxidation protein products (AOPP), and catalase, and the quantitative expression of the redox-sensitive transcription factor NF-κB p65 subunit. MATERIALS AND METHODS: This interventional follow-up study enrolled 40 participants of both sexes aged 28-78 years, with a median age of 56 years, where unstimulated saliva was collected before denture placement, immediately after the denture placement, and 24 h, 7 days, and 30 days after the denture placement. The most prominent ROS overproduction was reported on the seventh day (p < 0.05), followed by a significant fall in antioxidative defense. RESULTS: The NF-κB p65 subunit, whose expression pattern was highest in the same time period on the seventh day, serves as a signaling molecule for redox imbalance due to ROS production. Over the next 30 days, its levels remained moderately increased compared to the basal value, which may influence pro-inflammatory pathways and the integrity of oral tissue components. These alterations may be induced by the dentures, which can produce high pressures on the supporting tissues or by the synthetic materials used for producing the dentures. CONCLUSION: Our research may help to clarify the potential pathways by which oxidative stress and redox-sensitive inflammatory mediators, as well as mechanical and chemical irritants, may serve as risk factors for premalignant lesions in the mouth. Further research on this topic is required to understand the molecular mechanisms behind the relationship between inflammation and oral premalignant lesions caused by mechanical and chemical irritation.

Eco-Friendly Microwave Synthesis of Sodium Alginate-Chitosan Hydrogels for Effective Curcumin Delivery and Controlled Release.

In this study, we developed sodium alginate-chitosan hydrogels using a microwave-assisted synthesis method, aligning with green chemistry principles for enhanced sustainability. This eco-friendly approach minimizes chemical use and waste while boosting efficiency. A curcumin:2-hydroxypropyl-ß-cyclodextrin complex was incorporated into the hydrogels, significantly increasing the solubility and bioavailability of curcumin. Fourier Transform Infrared Spectroscopy (FTIR) analysis confirmed the structure and successful incorporation of curcumin, in both its pure and complexed forms, into the polymer matrix. Differential scanning calorimetry revealed distinct thermal transitions influenced by the hydrogel composition and physical cross-linking. Hydrogels with higher alginate content had higher swelling ratios (338%), while those with more chitosan showed the lowest swelling ratios (254%). Scanning Electron Microscopy (SEM) micrographs showed a porous structure as well as successful incorporation of curcumin or its complex. Curcumin release studies indicated varying releasing rates between its pure and complexed forms. The chitosan-dominant hydrogel exhibited the slowest release rate of pure curcumin, while the alginate-dominant hydrogel exhibited the fastest. Conversely, for curcumin from the inclusion complex, a higher chitosan proportion led to the fastest release rate, while a higher alginate proportion resulted in the slowest. This study demonstrates that the form of curcumin incorporation and gel matrix composition critically influence the release profile. Our findings offer valuable insights for designing effective curcumin delivery systems, representing a significant advancement in biodegradable and sustainable drug delivery technologies.

Liquid- and Semisolid-Filled Hard Gelatin Capsules Containing Alpha-Lipoic Acid as a Suitable Dosage Form for Compounding Medicines and Dietary Supplements.

Liquid-filled hard gelatin capsules may have pertinent advantages both for therapeutic effect and extemporaneous preparations of medicines. Alpha lipoic acid is a substance used in medicines and dietary supplements and there is a need for creating an appropriate formulation which would be suitable for each individual patient or consumer. Based on its biopharmaceutical and physical chemical characteristics, eight different capsule formulations were designed and characterized. Silicon dioxide was added to form a semisolid content and prevent leakage. The formulation filled with alpha lipoic acid solution in polyethylene glycol 400 showed the best performance. Although the addition of silicon dioxide to the formulation with polyethylene glycol 400 led to a change in both flow character and viscosity, the release rate did not show a statistically significant decrease (more than 85% of content was released after 5 min testing). Applied technique is a simple and an appropriate approach for compounding and could be used for other substances with similar properties.

Supercritical fluid technology as a strategy for nifedipine solid dispersions formulation: In vitro and in vivo evaluation.

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.

The Influence of Soft Segment Structure on the Properties of Polyurethanes.

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.

Biomedical Applications of Thermosensitive Hydrogels for Controlled/Modulated Piroxicam Delivery.

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.

The chemical characterisation of nettle (Urtica dioica L.) seed oil.

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.