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1.
Materials (Basel) ; 17(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38998187

RESUMO

The inherent brittleness of polyhydroxybutyrate (PHB), a well-studied polyhydroxyalkanoate (PHA), limits its applicability in flexible and impact-resistant applications. This study explores the potential of blending PHB with a different PHA to overcome brittleness. The synthesis of PHA polymers, including PHB and an amorphous medium-chain-length PHA (aPHA) consisting of various monomers, was achieved in previous works through canola oil fermentation. Detailed characterization of aPHA revealed its amorphous nature, as well as good thermal stability and shear thinning behavior. The blending process was carried out at different mass ratios of aPHA and PHB, and the resulting blends were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The blends exhibited complex DSC curves, indicating the presence of multiple crystalline forms of PHB. SEM images revealed the morphology of the blends, with PHB particles dispersed within the aPHA matrix. TGA showed similar thermal degradation patterns for the blends, with the residue content decreasing as the PHB content increased. The crystallinity of the blends was influenced by the PHB content, with higher PHB ratios resulting in an increased degree of crystallinity. XRD confirmed the presence of both α and ß crystals of PHB in the blends. Overall, the results demonstrate the potential of PHB+aPHA blends to enhance the mechanical properties of biopolymer materials, without com-promising the thermal stability, paving the way for sustainable material design and novel application areas.

2.
Pharm Stat ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978387

RESUMO

During the drug development process, testing potency plays an important role in the quality assessment required for the manufacturing and marketing of biologics. Due to multiple operational and biological factors, higher variability is usually observed in bioassays compared with physicochemical methods. In this paper, we discuss different sources of bioassay variability and how this variability can be statistically estimated. In addition, we propose an algorithm to estimate the variability of reportable results associated with different numbers of runs and their corresponding OOS rates under a given specification. Numerical experiments are conducted on multiple assay formats to elucidate the empirical distribution of bioassay variability.

3.
J Med Chem ; 67(13): 11053-11068, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38952152

RESUMO

Metastable binding sites (MBS) have been observed in a multitude of molecular dynamics simulations and can be considered low affinity allosteric binding sites (ABS) that function as stepping stones as the ligand moves toward the orthosteric binding site (OBS). Herein, we show that MBS can be utilized as ABS in ligand design, resulting in ligands with improved binding kinetics. Four homobivalent bitopic ligands (1-4) were designed by molecular docking of (S)-alprenolol ((S)-ALP) in the cocrystal structure of the ß2 adrenergic receptor (ß2AR) bound to the antagonist ALP. Ligand 4 displayed a potency and affinity similar to (S)-ALP, but with a >4-fold increase in residence time. The proposed binding mode was confirmed by X-ray crystallography of ligand 4 in complex with the ß2AR. This ligand design principle can find applications beyond the ß2AR and G protein-coupled receptors (GPCRs) as a general approach for improving the pharmacological profile of orthosteric ligands by targeting the OBS and an MBS simultaneously.


Assuntos
Simulação de Acoplamento Molecular , Receptores Adrenérgicos beta 2 , Receptores Adrenérgicos beta 2/metabolismo , Receptores Adrenérgicos beta 2/química , Ligantes , Humanos , Sítios de Ligação , Cristalografia por Raios X , Alprenolol/química , Alprenolol/farmacologia , Alprenolol/metabolismo , Antagonistas de Receptores Adrenérgicos beta 2/química , Antagonistas de Receptores Adrenérgicos beta 2/farmacologia , Antagonistas de Receptores Adrenérgicos beta 2/metabolismo , Simulação de Dinâmica Molecular , Desenho de Fármacos
4.
Materials (Basel) ; 17(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38893822

RESUMO

Pomegranate peel extract is known for its potent antibacterial, antiviral, antioxidant, anti-inflammatory, wound healing, and probiotic properties, leading to its use in treating oral infections. In the first stage of this work, for the first time, using the Design of Experiment (DoE) approach, pomegranate peel extract (70% methanol, temperature 70 °C, and three cycles per 90 min) was optimized and obtained, which showed optimal antioxidant and anti-inflammatory properties. The optimized extract showed antibacterial activity against oral pathogenic bacteria. The second part of this study focused on optimizing an electrospinning process for a combination of polycaprolactone (PCL) and polyvinylpyrrolidone (PVP) nanofibers loaded with the optimized pomegranate peel extract. The characterization of the nanofibers was confirmed by using SEM pictures, XRPD diffractograms, and IR-ATR spectra. The composition of the nanofibers can control the release; in the case of PVP-based nanofibers, immediate release was achieved within 30 min, while in the case of PCL/PVP, controlled release was completed within 24 h. Analysis of the effect of different scaffold compositions of the obtained electrofibers showed that those based on PCL/PVP had better wound healing potential. The proposed strategy to produce electrospun nanofibers with pomegranate peel extract is the first and innovative approach to better use the synergy of biological action of active compounds present in extracts in a patient-friendly pharmaceutical form, beneficial for treating oral infections.

6.
World J Biol Psychiatry ; 25(6): 342-351, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38905131

RESUMO

OBJECTIVES: This survey assessed psychiatry residents'/early-career psychiatrists' attitudes towards the utility of therapeutic drug monitoring (TDM) of antipsychotics. METHODS: A previously developed questionnaire on attitudes on TDM utility during antipsychotic treatment was cross-sectionally disseminated by national coordinators between 01/01/2022-31/12/2023. The frequency of using TDM for antipsychotics other than clozapine was the main outcome in a linear regression analysis, including sex, clinical setting, caseload, and factors generated by an exploratory factor analysis. Comparisons between residents and early-career psychiatrists, respondents working in in- and outpatient settings, and low-/middle- and high-income countries were performed. RESULTS: Altogether, 1,237 respondents completed the survey, with 37.9% having never used TDM for antipsychotics. Seven factors explained 41% of response variance; six of them were associated with frequency of TDM use (p < 0.05). Items with highest loadings for factors included clinical benefits of TDM (factors A and E: 0.7), negative expectations for beliefs of patients towards TDM (factor B: 0.6-0.7), weak TDM scientific evidence (factor C: 0.8), and TDM availability (factor D: -0.8). Respondents from low-/middle-income countries were less likely to frequently/almost always use TDM compared to high-income countries (9.4% vs. 21.5%, p < 0.001). DISCUSSION: TDM use for antipsychotics was poor and associated with limited knowledge and insufficient availability.


Assuntos
Antipsicóticos , Atitude do Pessoal de Saúde , Monitoramento de Medicamentos , Psiquiatria , Humanos , Antipsicóticos/uso terapêutico , Feminino , Masculino , Estudos Transversais , Inquéritos e Questionários , Adulto , Internato e Residência , Europa (Continente) , Padrões de Prática Médica/estatística & dados numéricos , Sociedades Médicas , Psiquiatras
7.
Psychiatr Pol ; 58(1): 7-24, 2024 Feb 28.
Artigo em Inglês, Polonês | MEDLINE | ID: mdl-38852182

RESUMO

OBJECTIVES: Anxiety disorders are significant predictors of suicidality and are proposed to be independent risk factors for suicide attempts. They are common in people with type 2 diabetes (T2DM) and are associated with longer duration of diabetes and poorer treatment outcomes. The aim was to examine associations between anxiety disorders and suicidal thoughts and behaviour in people with T2DM, to establish the prevalence of suicidality among people with T2DM in the selected European countries and to examine whether anxiety disorders were predictive of current outcomes of suicidality in this population using data from the International Prevalence and Treatment of Diabetes and Depression study. METHODS: The study sample comprised 1063 adults with T2DM from 6 European countries. The presence of anxiety disorders and suicidality was assessed with the MINI International Neuropsychiatric Interview. The group of participants with current suicidal risk was compared with the group of participants with no suicidal risk. RESULTS: The participants from Germany were more likely to report suicidality than those from other countries, whereas people from Serbia and Ukraine were less likely to report it. Depression and anxiety disorders significantly contributed to the increased presence of suicidality among people with T2DM. Agoraphobia was a significant predictor of suicidality when controlling for depression. The participants with T2DM and comorbid agoraphobia had 4.86 times higher odds to report suicidality than those without agoraphobia. CONCLUSIONS: Agoraphobia was a significant predictor of suicidality in people with T2DM.


Assuntos
Transtornos de Ansiedade , Diabetes Mellitus Tipo 2 , Ideação Suicida , Humanos , Diabetes Mellitus Tipo 2/psicologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Transtornos de Ansiedade/epidemiologia , Transtornos de Ansiedade/psicologia , Adulto , Europa (Continente)/epidemiologia , Fatores de Risco , Comorbidade , Idoso , Tentativa de Suicídio/estatística & dados numéricos , Tentativa de Suicídio/psicologia , Prevalência , Ucrânia/epidemiologia , Alemanha/epidemiologia
8.
Cancer Prev Res (Phila) ; : OF1-OF5, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38853442

RESUMO

Guideline recommended standard of care screening is available for four cancer types; most cancer-related deaths are caused by cancers without standard of care screening. DETECT-A is the first prospective interventional trial evaluating a multi-cancer early detection (MCED) blood test (CancerSEEK) in women without a history of cancer, providing the first opportunity to assess the long-term outcomes of individuals with false-positive (FP) MCED results. This prospective analysis of DETECT-A participants with FP results evaluates the performance of an imaging-based diagnostic workflow and examines cancer risk following a FP result. This analysis included all DETECT-A participants with a positive CancerSEEK test and subsequent flourine-18 fluorodeoxyglucose positron emission tomography-IV contrast-enhanced computed tomography (18-F-FDG PET-CT) imaging and clinical workup indicating no evidence of cancer within 1 year of enrollment (n = 98). Medical records, study interactions, and study surveys were used to assess cancer incidence, treatments, and clinical outcomes through August 2023. Ninety-five of 98 participants with a FP result remained cancer-free with a median follow-up of 3.6 years (IQR: 2.5-4.1) from determination of FP status. Three incident cancers were observed over the follow-up period. One bilateral stage IIIC ovarian cancer was diagnosed 1.9 years after determination of FP status; two stage I breast cancers were diagnosed 0.1 and 1.6 years from determination of FP status. The annual incidence rate of cancer during follow-up from FP determination was 1.0% (95% confidence interval, 0.2%-2.8%). Participants with a positive CancerSEEK test who underwent 18-F-FDG PET-CT and clinical workup without cancer findings had low risk for cancer over the following several years. Prevention Relevance: This study provides multiyear clinical outcomes data following a false-positive multi-cancer early detection test for individuals participating in a prospective interventional trial. It provides a preliminary performance assessment of an imaging-based diagnostic workflow following a false-positive multi-cancer early detection test.

9.
Heliyon ; 10(9): e30254, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707308

RESUMO

This literature review provides an up-to-date exploration of the multifaceted attributes of maitake mushrooms (Grifola frondosa), elucidating their bioactive phytochemicals and diverse health advantages, including their substantial role in supporting human health and potential incorporation into the medicinal industry. Carbohydrates and protein are the major constituents contributing to the dry weight of G. frondosa, taking up around 70-80 % and 13-21 %, respectively, with emerging research linking these constituents to various health benefits. By synthesising current research findings, this review emphasises the substantial role of maitake mushrooms in supporting human health and underscores their potential incorporation into the medicinal industry. To further advance our understanding, future research should delve into the mechanisms underlying their health-promoting effects, with a focus on conducting quantitative studies to elucidate physiological pathways and potential drug interactions. Additionally, exploring their integration into functional foods or nutraceuticals through quantitative assessments of bioavailability and efficacy will be crucial for maximising their therapeutic benefits. This review aims to provide comprehensive insights, catalysing further research and innovation in utilising maitake mushrooms for improved well-being and industry advancement.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38819783

RESUMO

In the U.S., <20% of cancers are diagnosed by standard-of-care (SoC) screening. Multi-cancer early detection (MCED) tests offer the opportunity to expand cancer screening. Understanding the characteristics and clinical outcomes of MCED-detected cancers is critical to clarifying MCED tests' potential impact. DETECT-A is the first prospective interventional trial of an MCED blood test (CancerSEEK). CancerSEEK, coupled with diagnostic PET-CT, identified cancers including those not detected by SoC screening, the majority of which were localized or regional. We report multi-year outcomes in patients with cancers diagnosed following a positive CancerSEEK test. Nine cancer types were diagnosed in 26 participants whose cancers were first detected by CancerSEEK. Information on cancer diagnoses, treatments, and clinical outcomes was extracted from medical records through November 2022. Data collection occurred a median of 4.4 years (IQR: 4.1-4.6) following study enrollment. Thirteen of 26 (50%) participants were alive and cancer-free [ovarian (4), thyroid (1), uterine (2), breast (1), colorectal (2), and lung (3)]; 7/13 (54%) had cancers without recommended SoC screening modalities. All 8 treated stage I or II participants (8/8, 100%) and 12/14 (86%) surgically-treated participants were alive and cancer-free. Eligibility for surgical treatment was associated with favorable multi-year outcomes (p = 0.0002). Half of participants with MCED-detected cancers were alive and cancer-free after 4.4 years median follow-up. Most were diagnosed with early-stage cancers and were treated surgically. These results suggest that early cancer detection by CancerSEEK may have facilitated curative-intent treatments and associated positive clinical outcomes in some DETECT-A participants.

11.
RSC Med Chem ; 15(5): 1751-1772, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38784477

RESUMO

Benzosiloxaboroles are an emerging class of medicinal agents possessing promising antimicrobial activity. Herein, the expedient synthesis of two novel thiol-functionalized benzosiloxaboroles 1e and 2e is reported. The presence of the SH group allowed for diverse structural modifications involving the thiol-Michael addition, oxidation, as well as nucleophilic substitution giving rise to a series of 27 new benzosiloxaboroles containing various polar functional groups, e.g., carbonyl, ester, amide, imide, nitrile, sulfonyl and sulfonamide, and pendant heterocyclic rings. The activity of the obtained compounds against selected bacterial and yeast strains, including multidrug-resistant clinical strains, was investigated. Compounds 6, 12, 20 and 22-24 show high activity against Staphylococcus aureus, including both methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) strains, with MIC values in the range of 1.56-12.5 µg mL-1, while their cytotoxicity is relatively low. The in vitro assay performed with 2-(phenylsulfonyl)ethylthio derivative 20 revealed that, in contrast to the majority of known antibacterial oxaboroles, the plausible mechanism of antibacterial action, involving inhibition of the leucyl-tRNA synthetase enzyme, is not responsible for the antibacterial activity. Structural bioinformatic analysis involving molecular dynamics simulations provided a possible explanation for this finding.

13.
J Med Chem ; 67(11): 8481-8501, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38769934

RESUMO

Metallacarboranes, exemplified by cobalt bis(dicarbollide) ([COSAN]-), have excelled their historical metallocene analogue label to become promising in drug design, medical studies, and fundamental biological research. Serving as a unique platform for conjugation with biomolecules, they also constitute an auspicious building block for biologically active derivatives and a carrier for cellular transport of membrane-impermeable cargos. Modified [COSAN]- exhibits specific antimicrobial, antiviral, and anticancer actions showing promise for preclinical trials. Contributing to the ongoing development in medicinal chemistry, metallacarboranes offer desirable physicochemical properties and low acute toxicity. This article presents a critical look at metallacarboranes in the context of their application in medicinal chemistry, emphasizing [COSAN]- as a potential game-changer in drug design and biomedical sciences. As medicinal chemistry seeks innovative building blocks, metallacarboranes emerge as an important novelty with versatile solutions and promising implications.


Assuntos
Química Farmacêutica , Cobalto , Humanos , Química Farmacêutica/tendências , Cobalto/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Boranos/química , Boranos/farmacologia , Boranos/síntese química , Desenho de Fármacos , Animais , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Compostos Organometálicos/síntese química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antivirais/química , Antivirais/farmacologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-38705577

RESUMO

Guideline recommended standard of care (SoC) screening is available for four cancer types; most cancer-related deaths are caused by cancers without SoC screening. DETECT-A is the first prospective interventional trial evaluating an MCED blood test (CancerSEEK) in women without a history of cancer, providing the first opportunity to assess the long-term outcomes of individuals with false positive (FP) MCED results. This prospective analysis of DETECT-A participants with FP results evaluates the performance of an imaging-based diagnostic workflow and examines cancer risk following a FP result. This analysis included all DETECT-A participants with a positive CancerSEEK test and subsequent flourine-18 fluorodeoxyglucose positron emission tomography-IV contrast enhanced computed tomography (18-F-FDG PET-CT) imaging and clinical workup indicating no evidence of cancer within one year of enrollment (n=98). Medical records, study interactions, and study surveys were used to assess cancer incidence, treatments, and clinical outcomes through August 2023. Ninety-five of 98 participants with a FP result remained cancer-free with a median follow-up of 3.6 years (IQR: 2.5-4.1) from determination of FP status. Three incident cancers were observed over the follow-up period. One bilateral stage IIIC ovarian cancer was diagnosed 1.9 years after determination of FP status; two stage I breast cancers were diagnosed 0.1 and 1.6 years from determination of FP status. The annual incidence rate of cancer during follow-up from FP determination was 1.0% (95% CI: 0.2%-2.8%). Participants with a positive CancerSEEK test who underwent 18-F-FDG PET-CT and clinical workup without cancer findings had low risk for cancer over the following several years.

15.
Clin Rev Allergy Immunol ; 66(2): 164-191, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38642273

RESUMO

Psoriasis is one of the most common inflammatory skin diseases with a chronic, relapsing-remitting course. The last decades of intense research uncovered a pathological network of interactions between immune cells and other types of cells in the pathogenesis of psoriasis. Emerging evidence indicates that dendritic cells, TH17 cells, and keratinocytes constitute a pathogenic triad in psoriasis. Dendritic cells produce TNF-α and IL-23 to promote T cell differentiation toward TH17 cells that produce key psoriatic cytokines IL-17, IFN-γ, and IL-22. Their activity results in skin inflammation and activation and hyperproliferation of keratinocytes. In addition, other cells and signaling pathways are implicated in the pathogenesis of psoriasis, including TH9 cells, TH22 cells, CD8+ cytotoxic cells, neutrophils, γδ T cells, and cytokines and chemokines secreted by them. New insights from high-throughput analysis of lesional skin identified novel signaling pathways and cell populations involved in the pathogenesis. These studies not only expanded our knowledge about the mechanisms of immune response and the pathogenesis of psoriasis but also resulted in a revolution in the clinical management of patients with psoriasis. Thus, understanding the mechanisms of immune response in psoriatic inflammation is crucial for further studies, the development of novel therapeutic strategies, and the clinical management of psoriasis patients. The aim of the review was to comprehensively present the dysregulation of immune response in psoriasis with an emphasis on recent findings. Here, we described the role of immune cells, including T cells, B cells, dendritic cells, neutrophils, monocytes, mast cells, and innate lymphoid cells (ILCs), as well as non-immune cells, including keratinocytes, fibroblasts, endothelial cells, and platelets in the initiation, development, and progression of psoriasis.


Assuntos
Células Dendríticas , Psoríase , Psoríase/imunologia , Psoríase/etiologia , Humanos , Células Dendríticas/imunologia , Animais , Queratinócitos/imunologia , Citocinas/metabolismo , Pele/imunologia , Pele/patologia , Transdução de Sinais , Células Th17/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
16.
Materials (Basel) ; 17(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673093

RESUMO

Marigold flower is a traditionally used plant material topically applied on the skin due to its anti-inflammatory properties and antibacterial activity. This potential of action justifies the implementation of marigold extract in nanofiber scaffolds based on poly-vinylpyrrolidone/hydroxypropyl-ß-cyclodextrin (PVP/HPßCD) and polycaprolactone/polyvinylpyrrolidone (PCL/PVP) obtained by electrospinning for wound treatment. Using SEM, the morphology of electrospun scaffolds showed a fiber diameter in the range of 298-527 nm, with a uniform and bead-free appearance. ATR-FTIR spectroscopy confirmed the presence of marigold extracts in nanofibrous scaffolds. The composition of the nanofibers can control the release; in the case of PVP/HPßCD, immediate release of 80% of chlorogenic acid (an analytical and functional marker for marigold extract) was achieved within 30 min, while in the case of PCL/PVP, the controlled release was achieved within 24 h (70% of chlorogenic acid). All systems showed weak antibacterial activity against skin and wound-infecting bacteria Staphylococcus aureus (MIC 100 mg/mL), and Pseudomonas aeruginosa (MIC 200 mg/mL) and yeasts Candida albicans (MIC 100 mg/mL). Analysis of the effect of different scaffold compositions of the obtained electrofibers showed that those based on PCL/PVP had better wound healing potential. The scratch was closed after 36 h, compared to the 48 h required for PVP/HPßCD. Overall, the study shows that scaffolds of PCL/PVP nanofibers loaded with classic marigold extract have the best potential as wound dressing materials because of their ability to selectively modulate inflammation (via inhibition of hyaluronidase enzyme) and supportive antimicrobial properties, thereby aiding in the early stages of wound healing and repair.

17.
ChemMedChem ; 19(14): e202400080, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619283

RESUMO

The 5-HT2A receptor is a molecular target of high pharmacological importance. Ligands of this protein, particularly atypical antipsychotics, are useful in the treatment of numerous mental disorders, including schizophrenia and major depressive disorder. Structure-based virtual screening using a 5-HT2A receptor complex was performed to identify novel ligands for the 5-HT2A receptor, serving as potential antidepressants. From the Enamine screening library, containing over 4 million compounds, 48 molecules were selected for subsequent experimental validation. These compounds were tested against the 5-HT2A receptor in radioligand binding assays. From the tested batch, six molecules were identified as ligands of the main molecular target and were forwarded to a more detailed in vitro profiling. This included radioligand binding assays at 5-HT1A, 5-HT7, and D2 receptors and functional studies at 5-HT2A receptors. These compounds were confirmed to show a binding affinity for at least one of the targets tested in vitro. The success rate for the inactive template-based screening reached 17 %, while it was 9 % for the active template-based screening. Similarity and fragment analysis indicated the structural novelty of the identified compounds. Pharmacokinetics for these molecules was determined using in silico approaches.


Assuntos
Receptor 5-HT2A de Serotonina , Receptor 5-HT2A de Serotonina/metabolismo , Receptor 5-HT2A de Serotonina/química , Ligantes , Humanos , Relação Estrutura-Atividade , Avaliação Pré-Clínica de Medicamentos , Descoberta de Drogas , Estrutura Molecular , Simulação de Acoplamento Molecular
19.
Front Psychiatry ; 15: 1340181, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455518

RESUMO

Background: The COVID-19 pandemic placed great strain on healthcare professionals, leading to a substantial impact and a redistribution of the workforce. Despite the active involvement of the Eastern Mediterranean Region Office (EMRO) and the World Health Organization in managing mental health crises, there is a knowledge gap concerning the working conditions and training opportunities available for early career psychiatrists (ECPs) during the pandemic period. Objectives: This study aims to investigate the impact of the COVID-19 pandemic on ECPs and how it affected their well-being, employment, and educational opportunities. Methods: A mixed methods study has been conducted in Iran, Egypt, and Tunisia, three EMRO member countries. It includes a cross-sectional survey with self-reported questions, and a qualitative study with individual in-depth interviews. Discussion: The findings of this study will raise awareness to the working conditions of ECPs within the EMRO region and its member societies, both during the COVID-19 pandemic and beyond. The results will serve as a basis for encouraging supervisors and policymakers to mitigate the pandemic's impact on psychiatric training, strengthen healthcare systems' preparedness, and equip early career psychiatrists with the necessary skills to deal with the mental health consequences of the COVID-19 pandemic.

20.
Materials (Basel) ; 17(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38541410

RESUMO

This study focuses on examining the influence of bast fibers on the flammability and thermal properties of the polylactide matrix (PLA). For this purpose, Urtica dioica and Vitis vinifera fibers were subjected to two types of modifications: mercerization in NaOH solution (M1 route) and encapsulation in an organic PLA solution (M2 route). In a further step, PLA composites containing 5, 10, and 15 wt% of unmodified and chemically treated fibers were obtained. The results of the tests show that only biocomposites containing mercerized fibers had a nearly 20% reduced flammability compared to that of PLA. Moreover, the biofiller obtained in this way belongs to the group of flame retardants that generate char residue during combustion, which was also confirmed by TGA tests. The M2 modification route allowed to achieve higher mass viscosity than the addition of unmodified and M1-modified fibers. The reason is that fibers additionally encapsulated in a polymer layer impede the mobility of the chain segments. The inferior homogenization of the M2-modified fibers in the PLA matrix translated into a longer combustion time and only a 15% reduction in flammability.

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