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1.
Polymers (Basel) ; 16(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38475351

RESUMO

Reducing the impact of some biological fluids on bioimplants involves the control of surface characteristics by modeling the interface architecture and assembling ecofriendly thin films to retard corrosion. Therefore, a mixture of hydrolyzed keratin peptides (HKER) was investigated as a corrosion inhibitor for 304L stainless steel (SS) in physiological serum (PS), using electrochemical measurements associated with optical microscopy and atomic force microscopy (AFM). The tests, performed for various concentrations of the inhibitor at different temperatures, showed that the inhibition efficiency (IE) decreased with a rise in temperature and proportionally increased with the HKER concentration, reaching its maximum level, around 88%, at 25 °C, with a concentration of 40 g L-1 HKER in physiological serum. The experimental data best fitted the El-Awady adsorption model. The activation parameters (Ea, ∆Ha and ∆Sa) and the adsorption ones (∆Gads0, ∆Hads, ∆Sads) have highlighted a mixed action mechanism of HKER, revealing that physisorption prevails over chemisorption. AFM parameters, such as the average roughness (Ra), root-mean-square roughness (Rq) and maximum peak-to-valley height (Rp-v), confirmed HKER adsorption, indicating that a smoother surface of the 304L stainless steel was obtained when immersed in a PS-containing inhibitor, compared to the surface designed in blank solution, due to the development of a protective layer on the alloy surface.

2.
Molecules ; 28(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37836642

RESUMO

Potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) were applied to study the inhibitory effect of N-acetylcysteine (NAC) on corrosion inhibition of carbon steel in hydrochloric acid solution. N-acetylcysteine influenced the iron dissolution to a greater extent than the hydrogen evolution reaction acting as a mixed inhibitor, predominantly anodic. The charge transfer resistance (Rct) gradually increased with the inhibitor concentration. From both methods, the inhibition efficiency (IE) reached a value of 89 ± 1% and NAC adsorption followed the Temkin isotherm. The value of adsorption Gibbs energy (ΔGadso), around -35 kJ mol-1, indicated a spontaneous adsorption and mixed action mechanism, with NAC chemical adsorption prevailing over physical one. New data will be reported by the computational study, that was performed using the density functional theory (DFT) method in aqueous phase. Quantum chemical descriptors were determined by B3LYP theory level with 6-31G+(d) basis set. Metropolis Monte Carlo atomistic simulation was used to reveal the adsorption configuration and interactions between acetylcysteine molecules and the carbon steel surface. Theoretical results were consistent with the experimental data, showing that the inhibitor action mechanism consisted of mainly chemisorption of its molecules on the carbon steel surface accompanied by van der Waals forces and electrostatic interactions.

3.
Healthcare (Basel) ; 10(8)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-36011065

RESUMO

Previous studies have shown an association between job demands and burnout in medical staff during the pandemic. However, these studies have ignored the possibility of loss cycle occurrence during the crisis. In order to address this gap, the aim of this study was to test the mediating role of burnout in the positive relationship between job demands and the self-undermining of healthcare employees during the COVID-19 pandemic. Self-undermining represents the set of behaviors that generate obstacles and diminish performance (e.g., careless mistakes, generating interpersonal conflicts, poor communication), and it has been suggested that this variable could explain the loss cycle between demands and burnout (the phenomenon in which demands increase burnout, which in turn leads to even greater demands). A total of 523 healthcare workers from two Romanian hospitals (e.g., physicians, nurses, stretcher-bearers) completed a self-report questionnaire during the COVID-19 outbreak that included three job demands, burnout, and self-undermining. Burnout mediated the positive relationship between two demands (work-family conflict; lack of equipment and supplies) and self-undermining. These results may provide a preliminary indication for the existence of loss cycles, supporting the assumptions of the job demands-resources theory. Moreover, the results highlight the risk of loss cycle occurrences for healthcare employees during outbreaks.

4.
Medicina (Kaunas) ; 58(7)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35888622

RESUMO

Angiogenesis is the process of developing new blood vessels from pre-existing ones. This review summarizes the main features of physiological and pathological angiogenesis and those of angiogenesis activation and inhibition. In healthy adults, angiogenesis is absent apart from its involvement in female reproductive functions and tissue regeneration. Angiogenesis is a complex process regulated by the action of specific activators and inhibitors. In certain diseases, modulating the angiogenic balance can be a therapeutic route, either by inhibiting angiogenesis (for example in the case of tumor angiogenesis), or by trying to activate the process of new blood vessels formation, which is the goal in case of cardiac or peripheral ischemia.


Assuntos
Doenças Cardiovasculares , Neoplasias , Inibidores da Angiogênese/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , Feminino , Humanos , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico
5.
Eval Health Prof ; 44(4): 406-415, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34579583

RESUMO

The Burnout Assessment Tool (BAT) represents a new measure of burnout that addresses the shortcomings of previous instruments. This study investigates the psychometric properties of the Romanian short version of the BAT. The sample consisted of 648 employees that completed the short version of the BAT. Of this sample, 117 employees also completed measures for other well-being indicators, job demands, job resources, personality, and organizational outcomes. According to our findings, there are strong correlations between the four core (exhaustion, emotional impairment, cognitive impairment, and mental distance) and two secondary (psychological distress and psychosomatic complaints) burnout symptoms. The scales presented appropriate reliability indicators. Results also support the convergent, discriminant, and construct validities. The Item Response Theory analysis showed a good coverage of the latent trait and the confirmatory factor analyses revealed appropriate fit indices. Theoretical and practical implications are discussed.


Assuntos
Esgotamento Psicológico , Esgotamento Psicológico/diagnóstico , Humanos , Psicometria/métodos , Reprodutibilidade dos Testes , Romênia , Inquéritos e Questionários
6.
Pharmaceuticals (Basel) ; 14(7)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199041

RESUMO

In order to anticipate the effect induced by a natural product on the chemical activity of medicines simultaneously administered, spontaneous interactions of certain cancer treatment drugs such as, epirubicin (EPR), gemcitabine (GCT), and paclitaxel (PTX) with limonene (LIM)-a natural compound extracted from orange peel and known as an anticancer agent-were investigated. To estimate the stability of the drugs over time, a current density of 50 mA cm-2 was applied as an external stimulus between two platinum electrodes immersed in hydrochloric acid solution containing ethyl alcohol/water in the volume ratio of 2/3, in the absence and presence of orange essential oil (limonene concentration of 95%). The concentration variation of chemotherapeutic agents over time was evaluated by UV-Vis spectrophotometry. Kinetic studies have shown a delay in the decomposition reaction of epirubicin and gemcitabine and a paclitaxel activity stimulation. Thus, in the presence of limonene, the epirubicin half-life increased from 46.2 min to 63 min, and from 6.2 min to 8.6 min in gemcitabine case, while for paclitaxel a decrease of half-life from 35.9 min to 25.8 min was determined. Therefore, certain drug-limonene interactions took place, leading to the emergence of molecular micro-assemblies impacting decomposition reaction of chemotherapeutics. To predict drug-limonene interactions, the Autodock 4.2.6 system was employed. Thus, two hydrophobic interactions and five π-alkyl interactions were established between EPR-LIM, the GCT-LIM connection involves four π-alkyl interactions, and the PTX-LIM bridges take place through three hydrophobic interactions and the one π-alkyl. Finally, the decomposition reaction mechanism of drugs was proposed.

7.
Healthcare (Basel) ; 9(3)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803286

RESUMO

The purpose of this study was to identify the predictors of burnout in healthcare workers during the COVID-19 pandemic. Data were collected from March to June in 2020, during the COVID-19 pandemic, from employees of two Romanian hospitals. Five hundred and twenty-three healthcare workers completed a series of questionnaires that measured burnout, job demands, job resources, and personal resources. Among the respondents, 14.5% had a clinical level of exhaustion (the central component of burnout). Three job demands (work-family conflict, lack of preparedness/scope of practice, emotional demands), three job resources (training, professional development, and continuing education; supervision, recognition, and feedback; autonomy and control), and one personal resource (self-efficacy) were significant predictors of burnout, explaining together 37% of the variance in healthcare workers' burnout. Based on our results, psychological interventions during the COVID-19 pandemic for healthcare employees should focus primarily on these demands and resources.

8.
Rom J Morphol Embryol ; 57(2): 427-35, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27516015

RESUMO

The overgrowth, depending on its extension, has multiple effects on the stomatognathic apparatus: functional disorders (impaired speech), difficulty in chewing and aesthetic problems but can cause significant psychological problems. We proposed this study, motivated by the relative increased frequency of the gum outgrowth, its multifactorial etiopathogeny, but especially from the point of view of the specialist practitioner, by the problems that this pathology raises not only for the functionality of the stomatognathic apparatus but also for the facial esthetics, and especially for future therapeutic attitudes needed to solve the existing pathology at this level. We conducted a clinical study and a histological one. For the clinical study, we selected 74 patients who experienced different degrees of gingival outgrowing associated with fillings, dental caries, fixed prostheses, mobile prostheses, orthodontic apparatus. Thirty gingival fragments from patients with gingival outgrowing were processed by paraffin-embedding histological technique and stained with Hematoxylin-Eosin. The morphological results obtained provide the necessary support for understanding the possibility of developing a therapeutic strategy to prevent or minimize the gum outgrowth by administering antibiotic and anti-inflammatory medications associated with medications, which shall cause the apoptosis of the fibroblasts.


Assuntos
Crescimento Excessivo da Gengiva/etiologia , Crescimento Excessivo da Gengiva/patologia , Adolescente , Adulto , Idoso , Epitélio/patologia , Feminino , Humanos , Inflamação/patologia , Masculino , Higiene Bucal , Adulto Jovem
9.
Rom J Morphol Embryol ; 56(2 Suppl): 843-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26429183

RESUMO

The precise prevalence of molluscum contagiosum (MC) is still unknown. The pediatric studies showed a cumulative incidence of 17% in children less than 15 years, but there are no studies available for Romania. The papular skin lesions are generally less than 5 mm, but the immunocompromised patients may develop large uncommon lesions. The pediatric cases are located mostly on the limbs, trunk or the face. The lab investigations are not usually required because the clinical features are typical. A biopsy followed by a light microscopy may help in some cases. We are presenting the case of a 6-year-old boy suffering from MC since almost a year. When examined in our clinic, the child developed 2 to 4 mm dome-shaped flesh-colored papules with central umbilication on his trunk diagnosed as MC. The microscopic examination revealed bud-like proliferation of the epidermis, molluscum bodies and moderate chronic inflammation of the dermis. In about one month of treatment, all the lesions disappeared without other local or general complications.


Assuntos
Molusco Contagioso/diagnóstico , Molusco Contagioso/patologia , Pele/patologia , Biópsia , Criança , Eritema/patologia , Humanos , Inflamação , Masculino , Resultado do Tratamento
10.
Rom J Morphol Embryol ; 55(3 Suppl): 1137-41, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25607396

RESUMO

There is scientific data to support the existence of a two-way relationship between diabetes and periodontitis, with diabetes increasing the risk for periodontitis, and periodontal inflammation negatively affecting the diabetic status. Our study aims to investigate the expression of MMP-7, -8, -9 and -13 in the gingiva of the young patients with aggressive periodontitis (AP) and type 1 diabetes mellitus (T1D). Gingival biopsies were harvested from five adult patients aged 19-29 years with T1D+AP with moderate (three cases) to severe (two cases) forms of AP and from four adult patients aged 18-28 years with moderate AP without T1D. The MMP-7 immunoreaction was positive in the five cases with T1D+AP with different staining patterns. The MMP-8 immunostaining was positive in all cases. The reaction was more intense in cases with T1D+AP, especially in those with severe periodontitis. The MMP-9 immunoreaction was present in all the structures of the gingival mucosa with different intensity, being frequently present surrounding the blood vessels of the chorion. In most of the patients, reaction to MMP-9 was intense, localized at the level of the cells in the superficial chorion and very rarely at the level of some dispersed cells in the connective vascular islands. MMP-13 was present in all cases, but it was more intense in the two cases with T1D+AP with probing depth (PD)>6 mm when it had similar patterns as MMP-9 staining and in one case with AP when the staining was observed strictly in the lamina propria associated with moderate chronic inflammatory infiltrate. The expression of MMP-7, -8, -9 and -13 in the gingiva of the young patients with aggressive periodontitis and T1D was positive in all studied cases supporting the hypothesis that both are inflammatory diseases with common pathogenic mechanisms involving inflammatory mediators and may be possible biomarkers of disease status.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/enzimologia , Gengiva/enzimologia , Metaloproteinases da Matriz/metabolismo , Periodontite/complicações , Periodontite/enzimologia , Adolescente , Adulto , Diabetes Mellitus Tipo 1/patologia , Gengiva/patologia , Humanos , Imuno-Histoquímica , Periodontite/patologia , Adulto Jovem
11.
Rom J Morphol Embryol ; 55(4): 1521-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25611292

RESUMO

This is the report of a case of four upper incisors with multiple internal/external resorptions after a falling accident in the childhood and subsequent violation of the biologic width by incorrect individual coronal restorations. Endodontic orthograde retreatment was performed and mineral trioxide aggregate (MTA) was placed as apical plug and to repair the large internal resorption. In order to re-establish the biologic width, a controlled surgical crown-lengthening procedure was performed. The expression of matrix metalloproteinase (MMP)-9 in the gingival tissue was used as a biomarker for the presence of inflammation in the hypertrophied gingiva. The one-year control revealed the cessation of the resorptive activities and the stability of the periodontium. The choice for a conservative combined treatment was essential in maintaining the affected teeth in an esthetically challenging area.


Assuntos
Incisivo/patologia , Ferimentos e Lesões/patologia , Ferimentos e Lesões/terapia , Feminino , Gengiva/diagnóstico por imagem , Gengiva/patologia , Guta-Percha/uso terapêutico , Humanos , Imuno-Histoquímica , Incisivo/diagnóstico por imagem , Metaloproteinase 9 da Matriz/metabolismo , Radiografia , Reabsorção da Raiz/diagnóstico por imagem , Reabsorção da Raiz/patologia , Reabsorção da Raiz/terapia , Adulto Jovem
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