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This paper reports on some properties of pure and iron doped samples of hydroxyapatite composition prepared by coprecipitation method. The samples were characterized by X-ray photoelectron spectroscopy (XPS) and powder X-ray diffraction (XRD). The XPS results show on surface of both undoped and iron doped samples a Ca/P atomic ratio close to 1.67 typical for hydroxyapatite. According to XRD results, the addition of 0.1 wt % Fe2O3 promotes in the sample of pure hydroxyapatite composition the growth of nanocrystalline hydroxyapatite. [ABSTRACT FROM AUTHOR]

Abstract: Melt derived glasses of (1-x)B2O3∙xBi2O3 system with 0.1≤×≤0.875 were investigated by X-ray photoelectron spectroscopy (XPS) in order to evidence the structural changes that occur at the surface of bismuth borate glasses as Bi/B ratio increases from 1:9 to 7:1. The high resolution XPS spectra of O 1s, Bi 4f and B 1s photoelectrons emphasizes consistent changes in the vicinity of oxygen, and small changes around bismuth and boron atoms by increasing of Bi2O3 content. The deconvolution of O 1s spectra was used to investigate the Bi/B ratio effect on the number of bridging and non-bridging oxygens and the results obtained were discussed considering four components occurring from oxygen atoms implied in B O B, B O Bi, Bi O Bi and B O /Bi O bonds. From the deconvolution of Bi 4f high resolution spectra, four components related to Bi0 and bismuth atoms connected in bonds of Bi O Bi, B O Bi and Bi O types were identified. It was concluded that boron and bismuth play a network former role in the entire compositional range. [Copyright &y& Elsevier]

X-ray photoelectron spectroscopy (XPS) was employed to investigate B2O3-Bi2O3 vitreous samples with different of B/Bi ratios, considering the large interest for heavy-metal glasses based on Bi2O3 oxide present in field of optical and electronic devices. The glass samples have been prepared by melting technique. From the analysis of the XPS spectra for the Bi 4p, B 1s and O 1s core levels, several changes are identified in terms of various structural units being present, reflected by the changes occurred in the atomic environments of bismuth and boron atoms. All O 1s spectra were deconvoluted into two Lorentzian-Gaussian peaks corresponding to bridging and non-bridging oxygen atoms and the variation in the ratio of their peak areas is discussed in terms of the local structure as well. [ABSTRACT FROM AUTHOR]

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 (E a , ∆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 ( R a ), root-mean-square roughness ( R q ) and maximum peak-to-valley height ( R p-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.

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 (R ct ) 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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Dental trauma creates serious functional, aesthetic and psychological problems for the patient. The known developments in recent years in the area of materials and techniques related to direct composite resin restorations provide for the dentists direct conservative solutions that allow both morphology and aesthetic restoration and preservation of pulp vitality in many of the clinical situations encountered. A careful clinical examination and an accurate diagnosis (in terms of classification of the trauma) will allow the dentist to choose the most conservative therapeutic solution. We recommend the use of the diagnostic and therapeutic guidelines mentioned in the article.

Introduction: In this study, we aim to compare the levels of matrix metalloproteinase 9 (MMP9) in the gingival crevicular fluid (GCF), as indicators for healing, in two groups of patients - operated with a classic periodontal surgical technique and the same technique but using a dental microscope., Materials: We included 14 patients with ages between 12 and 26 years, average 14±6.2 years. Eight patients were women and six men. All patients presented gingival hypertrophy because of the orthodontic treatment on the mandibular arch. We performed gingivectomy on one-half of the mandibular arch by classic periodontal surgery and on the other half of the mandibular arch by a microscope-assisted gingivectomy., Methods: In the hypertrophied gingiva, the expression of MMP9 was identified using immunohistochemical-staining techniques. For immunological determination of MMP9 in GCF we performed Elisa tests., Results: We found different levels in different moments of the healing process for the two hemiarcades., Conclusions: We consider that faster healing in case of microscope-assisted gingivectomy may be related to the expression of MMP-9 in the GCF.

Unlabelled: Levels of metalloproteinase 8 (MMP8) in gingival crevicular fluid were studied in case of treatment with fixed orthodontic appliances. It were found a relationship between its levels and stages of the treatment under a good control of the bacterial plaque. Gingival overgrowth (GO) during the orthodontic treatment was traditionally considered as an inflammatory reaction consecutive of bacterial plaque accumulation because of difficult hygiene in those patients. Our study starts from the hypothesis that the gingival volume growth during the fixed orthodontic treatment appears at the beginning, without any inflammatory signs, as a result of the mechanical stress and periodontal remodeling during the orthodontic dental movement, the MMP8 acting as an indicator of this situation., Material and Methods: Twenty-two patients received a fixed orthodontic treatment. Periodontal examination took place one hour before and one hour, four and eight hours and weekly after until eight weeks. At each session gingival crevicular fluid (GCF) was sampled and the level of MMP8 was determined. At the appearance of gingival overgrowth (GO) gingivectomy was performed., Results: In the 13 patients that did not develop gingival overgrowth, the levels of MMP8 increased in the first 4-8 hours after orthodontic appliance and then fall to the initial level. In the nine patients with gingival overgrowth, the MMP8 levels in GCF continued to rise until the appearance of GO. In cases of GO with inflammation the levels of MMP8 were significantly higher than in cases of GO without inflammation. The expression of MMP8 in hypertrophied gingiva was more intensive in cases of GO with inflammation., Conclusions: It is possible that the MMP8 values in GCF to be a marker of the GO onset. MMP8 determination and monitoring at shorter time intervals may lead to a better control of the bacterial plaque and avoidance of gingival inflammation.

Metaplasia represents the process of transforming a well-differentiated adult tissue into another type of adult tissue. Pancreatic metaplasia of the gastric mucosa represents the process in which the normal mucosa of the stomach is replaced with pancreatic formations, which mimic the structure of pancreatic acini. We describe the case of a male patient aged 39 who was admitted for abdominal pain, vomiting, hematemesis, melena, pale teguments, intense perspiration and nausea. The patient underwent surgery for suturing a perforated duodenal ulcer five years prior to this episode (2002). A gastric ulcer complicated with superior digestive bleeding and a chronic duodenal ulcer complicated with partial stenosis and perivisceritis were found during surgery. Gastric wall fragments were harvested and underwent usual histological techniques and immunohistochemistry. We found an ulceration from the gastric mucosa to the submucosa, covered by fibrino-leukocytic detritus. In the mucosal chorion we found numerous round or oval shaped nested formations which occupied the lower two thirds of the chorion, to the muscularis mucosae. Some metaplasic acini contain cells variable in shape, color and immunophenotype. Surrounding the nested acini we found tubular formations, formed of cubic shaped cells, representing excretory canals which were continued by gastric glands or opened directly in the crypts of the gastric epithelium.

The orthodontic treatment uses forces that produce structural and biochemical changes in the periodontal space breaking the balance between the synthesis and the breakdown of the collagen in the periodontium. Matrix metalloproteinases (MMP) plays a central role in the normal tissular remodeling processes, those in the tissular morphogenesis and the tissular repair (including the remodeling of the periodontal space of the periodontal ligament, during the dental orthodontic translations). The inter-relation between the molecular mechanism of orthodontic remodeling and MMPs is still unclear.

In an effort to identify new proteins involved in functional recovery after cerebral ischemia, young (3 months) and aged (18 months) male rats were subjected to middle cerebral artery (MCA) occlusion. Brains were harvested at 3- and 14-days post ischemia and proteins from the peri-infarcted and the corresponding contralateral area and total proteins were analyzed by two-dimensional polyacrylamide gel electrophoresis followed by mass spectrometry analysis. Annexin A3 (ANXA3) was identified as one upregulated protein in the post-ischemic rat brain. Using western blotting, real-time PCR and immunohistochemistry, we confirmed that at 3-14 days post-stroke, ANXA3 expression in the peri-infarct area was consistently increased over the corresponding area of control rats. Double staining revealed that ANXA3 is produced by activated microglial cells. We found that aged rats also had more newly proliferating cells expressing ANXA3 than young rats do. Occasionally, ANXA3-immunopositive cells wraped around neurons, suggesting that annexin A3 may be involved in the removal of dying neurons after stroke.