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1.
Materials (Basel) ; 16(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38068147

RESUMO

The paper presents the results of preliminary research on the possibility of synthesizing ZnO-TiO2 mixed coatings by plasma electrochemical oxidation (PEO). The aim of the work was to synthesize TiO2-ZnO mixed coatings on a titanium substrate from an electrolyte containing ZnO nanoparticles (NPs) and to assess the parameters of PEO on the structure, chemical composition, and properties of the obtained oxide coatings. The PEO process was carried out under various current-voltage conditions using different signals: DC, DC pulse, and AC. In this work, optimal conditions for the PEO process were determined to obtain well-adhering oxide coatings with the highest possible content of ZnO. The structure and morphology of the resulting oxide coatings were investigated, and their chemical and phase composition was comprehensively examined (EDX, XRD, XPS, and GD-OES). In addition, their basic optical properties were assessed. It has been shown that in the PEO DC pulse process, it is possible to obtain oxide coatings characterized by a high degree of structure order, high ZnO content in the oxide coating (3.6 at.%, XPS), and prospective applications for photocatalytic purposes (3.12 eV).

2.
ACS Appl Mater Interfaces ; 15(16): 19863-19876, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37041124

RESUMO

Dental implants have become a routine, affordable, and highly reliable technology to replace tooth loss. In this regard, titanium and its alloys are the metals of choice for the manufacture of dental implants because they are chemically inert and biocompatible. However, for special cohorts of patients, there is still a need for improvements, specifically to increase the ability of implants to integrate into the bone and gum tissues and to prevent bacterial infections that can subsequently lead to peri-implantitis and implant failures. Therefore, titanium implants require sophisticated approaches to improve their postoperative healing and long-term stability. Such treatments range from sandblasting to calcium phosphate coating, fluoride application, ultraviolet irradiation, and anodization to increase the bioactivity of the surface. Plasma electrolytic oxidation (PEO) has gained popularity as a method for modifying metal surfaces and delivering the desired mechanical and chemical properties. The outcome of PEO treatment depends on the electrochemical parameters and composition of the bath electrolyte. In this study, we investigated how complexing agents affect the PEO surfaces and found that nitrilotriacetic acid (NTA) can be used to develop efficient PEO protocols. The PEO surfaces generated with NTA in combination with sources of calcium and phosphorus were shown to increase the corrosion resistance of the titanium substrate. They also support cell proliferation and reduce bacterial colonization and, hence, lead to a reduction in failed implants and repeated surgeries. Moreover, NTA is an ecologically favorable chelating agent. These features are necessary for the biomedical industry to be able to contribute to the sustainability of the public healthcare system. Therefore, NTA is proposed to be used as a component of the PEO bath electrolyte to obtain bioactive surface layers with properties desired for next-generation dental implants.


Assuntos
Implantes Dentários , Titânio , Humanos , Titânio/química , Ácido Nitrilotriacético , Propriedades de Superfície , Oxirredução , Metais , Ligas , Eletrólitos , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química
3.
Psychol Health Med ; 28(1): 179-188, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35380074

RESUMO

The objective of this paper was to assess the impact of the COVID-19 pandemic on the mental health of Poles and the availability of psychiatric and psychological support during the pandemic. A prospective, cross-sectional web-based survey design was adopted. It was carried out on a sample of 1080 Polish citizens above 18 years old. The majority of Poles (70%) experienced symptoms of mental disorders during the COVID-19 pandemic. Sleep disturbance (63.79%), anxiety (48.79%), low mood for most of the day (44.63%), sadness, tearfulness (41.29%), and concentration disorders (35.93%) were the mental disorder symptoms reported most often by the survey subjects. To reduce the potential acute and long-lasting effects of the COVID-19 pandemic on mental health, decision-makers of the Polish health system should implement stepped multilevel and multi-target psychological support services.


Assuntos
COVID-19 , Humanos , Adolescente , COVID-19/epidemiologia , Saúde Mental , Pandemias , Polônia/epidemiologia , SARS-CoV-2 , Estudos Transversais , Estudos Prospectivos , Controle de Doenças Transmissíveis , Ansiedade/epidemiologia , Ansiedade/psicologia , Depressão/epidemiologia , Depressão/psicologia
4.
Molecules ; 26(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917454

RESUMO

The biodegradable metals, including magnesium (Mg), are a convenient alternative to permanent metals but fast uncontrolled corrosion limited wide clinical application. Formation of a barrier coating on Mg alloys could be a successful strategy for the production of a stable external layer that prevents fast corrosion. Our research was aimed to develop an Mg stable oxide coating using plasma electrolytic oxidation (PEO) in silicate-based solutions. 99.9% pure Mg alloy was anodized in electrolytes contained mixtures of sodium silicate and sodium fluoride, calcium hydroxide and sodium hydroxide. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), contact angle (CA), Photoluminescence analysis and immersion tests were performed to assess structural and long-term corrosion properties of the new coating. Biocompatibility and antibacterial potential of the new coating were evaluated using U2OS cell culture and the gram-positive Staphylococcus aureus (S. aureus, strain B 918). PEO provided the formation of a porous oxide layer with relatively high roughness. It was shown that Ca(OH)2 was a crucial compound for oxidation and surface modification of Mg implants, treated with the PEO method. The addition of Ca2+ ions resulted in more intense oxidation of the Mg surface and growth of the oxide layer with a higher active surface area. Cell culture experiments demonstrated appropriate cell adhesion to all investigated coatings with a significantly better proliferation rate for the samples treated in Ca(OH)2-containing electrolyte. In contrast, NaOH-based electrolyte provided more relevant antibacterial effects but did not support cell proliferation. In conclusion, it should be noted that PEO of Mg alloy in silicate baths containing Ca(OH)2 provided the formation of stable biocompatible oxide coatings that could be used in the development of commercial degradable implants.


Assuntos
Eletrólise , Magnésio/farmacologia , Gases em Plasma/química , Silicatos/química , Antibacterianos/farmacologia , Líquidos Corporais/química , Cálcio/análise , Linhagem Celular Tumoral , Sobrevivência Celular , Materiais Revestidos Biocompatíveis/farmacologia , Eletrodos , Humanos , Luminescência , Testes de Sensibilidade Microbiana , Oxirredução , Fósforo/análise , Soluções , Espectrometria por Raios X , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
5.
Mater Sci Eng C Mater Biol Appl ; 119: 111607, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321651

RESUMO

Plasma Electrolytic Oxidation (PEO) is as a promising technique to modify metal surfaces by application of oxide ceramic coatings with appropriate physical, chemical and biological characteristics. Therefore, objective of this research was to find the simplest settings, yet able to produce relevant bioactive implant surfaces layers on Ti implants by means of PEO. We show that an electrolyte containing potassium dihydrogen phosphate as a source of P and either calcium hydroxide or calcium formate as a source of Ca in combination with a chelating agent, ethylenediamine tetraacetic acid (EDTA), is suitable for PEO to deliver coatings with desired properties. We determined surface morphology, roughness, wettability, chemical and phase composition of titanium after the PEO process. To investigate biocompatibility and bacterial properties of the PEO oxide coatings we used microbial and cell culture tests. The electrolyte based on Ca(OH)2 and EDTA promotes active crystallization of apatites after PEO processing of the Ti implants. The PEO layers can increase electrochemical corrosion resistance. The PEO can be potentially used for development of bioactive surfaces with increased support of eukaryotic cells while inhibiting attachment and growth of bacteria without use of antibacterial agents.


Assuntos
Implantes Dentários , Titânio , Cálcio , Cerâmica/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Oxirredução , Fósforo , Propriedades de Superfície , Titânio/farmacologia
6.
J Equine Vet Sci ; 88: 102972, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32303320

RESUMO

We hypothesized that in horses with naturally occurring joint disorders, the neutrophil response, acute phase response (APR), and oxidative stress parameters elevated significantly and are markers of increased inflammatory response in these conditions. Therefore, the first aim of the study was to evaluate neutrophil response, oxidative status, and APR. The neutrophil activity was assessed on the basis of elastase, myeloperoxidase (MPO), and alkaline phosphatase release, whereas free radical generation was assessed on the basis of nitric oxide and superoxide production. Acute phase response was estimated on the basis of fibrinogen or haptoglobin plasma concentration and oxidative stress on the basis of malondialdehyde plasma concentration. Then, these parameters were compared with lameness grade, and correlation coefficients between them were calculated. The study was conducted on 43 horses divided on control group of healthy horses (n = 17), acute lameness (AL) group (11 horses), and chronic lameness (CL) group (15 horses). The neutrophil activity from horses of both groups of joint disorders (AL and CL) was significantly (P < .01) higher in comparison with healthy horses. Elastase release was 67.28 ± 1.89% of maximal activity in AL group in comparison with 51.72 ± 1.75% in healthy horses and 62.61 ± 1.54% in CL group. The highest values of other enzymes were also noted in AL group. Moreover, in AL group release of elastase and MPO positively correlated (P < .01) with grades of lameness. These findings revealed the mutual relation between studied parameters and obtained results may be useful in the development of new therapeutic strategies in the treatment of acute and chronic joint disorders in horses.


Assuntos
Reação de Fase Aguda , Doenças dos Cavalos , Reação de Fase Aguda/veterinária , Animais , Marcha , Cavalos , Neutrófilos , Estresse Oxidativo
7.
Materials (Basel) ; 12(22)2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31766225

RESUMO

Plasma electrolytic oxidation (PEO) can provide an ideal surface for osteogenic cell attachment and proliferation with further successful osteointegration. However, the same surface is attractive for bacteria due to similar mechanisms of adhesion in prokaryotic and eukaryotic cells. This issue requires the application of additional surface treatments for effective prevention of postoperative infectious complications. In the present work, ZrNb alloy was treated in a Ca-P solution with Ag nanoparticles (AgNPs) for the development of a new oxide layer that hosted osteogenic cells and prevented bacterial adhesion. For the PEO, 0.5 M Ca(H2PO2)2 solution with 264 mg L-1 of round-shaped AgNPs was used. Scanning electron microscopy with energy-dispersive x-ray and x-ray photoelectron spectroscopy were used for morphology and chemical analysis of the obtained samples; the SBF immersion test, bacteria adhesion test, and osteoblast cell culture were used for biological investigation. PEO in a Ca-P bath with AgNPs provides the formation of a mesoporous oxide layer that supports osteoblast cell adhesion and proliferation. Additionally, the obtained surface with incorporated Ag prevents bacterial adhesion in the first 6 h after immersion in a pathogen suspension, which can be an effective approach to prevent infectious complications after implantation.

8.
Mater Sci Eng C Mater Biol Appl ; 104: 109957, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500028

RESUMO

The present work concerns the surface modification of The Ti-13Nb-13Zr alloy by electropolishing and plasma electrolytic oxidation (PEO) process in Ca-containing electrolytes: calcium formate and calcium lactate solutions (0.1-1.0 mol dm-3) under voltages of 200 and 400 V. As a result of the PEO process, a porous oxide layer containing incorporated calcium compounds was formed on the Ti-13Nb-13Zr alloy surface. The morphology and chemical composition of the modified Ti-13Nb-13Zr alloy were investigated using scanning electron microscopy (SEM + EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). An increase in the applied voltage caused an increase in the number of pores and an increase in the amount of calcium incorporated in the oxide layer. Analysis showed that all samples were covered by titanium oxide, which was present in the form of anatase and/or rutile. In course of the experiments, it was showed that the proposed procedure has a positive effect on the overall bioactivity of the Ti-13Nb-13Zr alloy. Bioactivity investigations using simulated body fluid (SBF) confirmed the formation of apatite on the anodized surfaces. The cell adhesion results obtained by the use of human bone marrow mesenchymal stem cells (hBMSC) demonstrated that the PEO coatings on the Ti-13Nb-13Zr alloy remarkably enhanced the cytocompatibility of the substrate, indicating a potential application in orthopedic surgeries. The incorporation of Ca into the oxide layer proceeded to a higher extent when the PEO treatment was performed in the calcium lactate bath. The oxide layers formed in the calcium lactate solution exhibited also superior biological behavior towards hBMSC. This can be ascribed to the presence of carboxylic groups onto coatings' surface (as identified by XPS), which facilitated the anchoring of cells and tissues.


Assuntos
Ligas/química , Materiais Biocompatíveis/química , Cálcio/química , Íons/química , Óxidos/química , Titânio/química , Adulto , Idoso , Apatitas/química , Compostos de Cálcio/química , Eletrodos , Feminino , Humanos , Lactatos/química , Masculino , Teste de Materiais , Microscopia Eletrônica de Varredura/métodos , Pessoa de Meia-Idade , Oxirredução , Porosidade , Propriedades de Superfície , Difração de Raios X/métodos
9.
J Vet Res ; 63(2): 235-242, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31276063

RESUMO

INTRODUCTION: Antimicrobial peptides (AMP) are a large group of innate immune effectors, which apart from antimicrobial activity show immunomodulative properties. Platelet-rich plasma (PRP) is a source of autologous growth factors and is used for stimulation of bone and soft tissue healing. The purpose of this study was to assess the influence of PRP and AMP extract on ovine monocyte-derived macrophage cultures. MATERIAL AND METHODS: The study was conducted on ovine macrophages (Mfs) previously stimulated with LPS or dexamethasone and then with preparations of PRP or AMP. Following activation of the Mfs their morphological and functional features were assessed. RESULTS: The study revealed pro-inflammatory influence of both examined preparations on Mfs cultures on the basis of morphology, ROS generation and arginase activity. Both preparations enhanced the pro-inflammatory response of cultured Mfs. CONCLUSION: This activity may intensify the antimicrobial action of Mfs, however, in cases of excessive and prolonged inflammation the use of these preparations should be limited.

10.
Chemosphere ; 212: 143-151, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30144675

RESUMO

The aim of this study was to evaluate the treatment of organic-carbon-deficient wastewater containing benzotriazole (BTA) in lab-scale aerated biofilters filled with natural manganese oxide ore, sand coated with synthetic manganese oxides and sand (as a control material) in terms of BTA removal efficiency, its transformation products and ecotoxicological impact of the treated wastewater. Additionally, the effect of Mn(II) feeding was tested. The removal of BTA in all the biofilters was ≥97%. The contribution of the biotic removal of this compound was 15%, 50%, and 75% in the systems filled with sand, synthetic and natural manganese oxides, respectively. Only the columns filled with natural manganese oxides provided significant removal of DOC and decrease of UV254 and SUVA254, with even more pronounced effect with Mn(II) feeding. The presence of Mn(II) was also found to enhance the removal of NNH4 in the systems filled with either form of manganese oxides, otherwise the removal of NNH4 was negligible or negative. The transformation reactions of BTA were methylation, hydroxylation, and triazole ring cleavage. Based on the number of compounds and their relative abundance, the methylated transformation products were predominant in the effluent. The reduction of the ecotoxicity (Microtox bioassay) of the effluents was positively correlated with the decrease of UV254, SUVA and DOC and only moderately with the removal of BTA. This study has shown that the natural manganese oxide ore provides the broadest set of services as a filtering material for aerated biofilters treating carbon-deficient wastewater containing BTA.


Assuntos
Manganês/química , Triazóis/isolamento & purificação , Águas Residuárias/química , Purificação da Água/métodos , Carbono , Compostos de Manganês , Óxidos
11.
J Mater Sci Mater Med ; 28(11): 173, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28956213

RESUMO

The susceptibility to the fouling of the NiTi and Ti6Al4V alloys due to the adhesion of microorganisms and the biofilm formation is very significant, especially in the context of an inflammatory state induced by implants contaminated by bacteria, and the implants corrosion stimulated by bacteria. The aim of this work was to examine the differences between the sulphur-oxidizing bacteria (SOB) and sulphate-reducing bacteria (SRB) strains in their affinity for NiTi and Ti6Al4V alloys. The biofilms formed on alloy surfaces by the cells of five bacterial strains (aerobic SOB Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans, and anaerobic SRB Desulfovibrio desulfuricans-3 strains) were studied using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The protein concentrations in liquid media have also been analyzed. The results indicate that both alloys tested may be colonized by SOB and SRB strains. In the initial stage of the biofilm formation, the higher affinity of SRB to both the alloys has been documented. However, the SOB strains have indicated the higher (although differentiated) adaptability to changing environment as compared with SRB. Stimulation of the SRB growth on the alloys surface was observed during incubation in the liquid culture media supplemented with artificial saliva, especially of lower pH (imitated conditions under the inflammatory state, for example in the periodontitis course). The results point to the possible threat to the human health resulting from the contamination of the titanium implant alloys surface by the SOB (A. thiooxidans and A. ferrooxidans) and SRB (D. desulfuricans).


Assuntos
Acidithiobacillus thiooxidans/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Desulfovibrio desulfuricans/efeitos dos fármacos , Níquel/farmacologia , Titânio/farmacologia , Acidithiobacillus thiooxidans/metabolismo , Acidithiobacillus thiooxidans/fisiologia , Ligas , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Desulfovibrio desulfuricans/metabolismo , Desulfovibrio desulfuricans/fisiologia , Humanos , Testes de Sensibilidade Microbiana , Níquel/química , Oxirredução , Sulfatos/metabolismo , Enxofre/metabolismo , Propriedades de Superfície , Titânio/química
12.
Front Neurosci ; 10: 453, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27766069

RESUMO

In our clinic invasive transtympanal promontory positive DC stimulations were first used, with a success rate of 42%. However, non-invasive hydrotransmissive negative DC stimulations are now favored, with improvement being obtained in 37.8% directly after the treatment, and 51.3% in a follow up 1 month after treatment. The further improvement after 1 month may be due to neuroplastic changes at central level as a result of altered peripheral input. The aim of the study was to determine how/whether a single electrical stimulation of the ear influences cortical activity, and whether changes observed in tinnitus after electrical stimulation are associated with any changes in cortical activity recorded in EEG. The study included 12 tinnitus patients (F-6, M-6) divided into two groups. Group I comprised six patients with unilateral tinnitus - unilateral, ipsilateral ES was performed. Group II comprised six patients with bilateral tinnitus-bilateral ES was performed. ES was performed using a custom-made apparatus. The active, silver probe-was immersed inside the external ear canal filled with saline. The passive electrode was placed on the forehead. The stimulating frequency was 250 Hz, the intensity ranged from 0.14 to 1.08 mA. The voltage was kept constant at 3 V. The duration of stimulation was 4 min. The EEG recording (Deymed QEST 32) was performed before and after ES. The patients assessed the intensity of tinnitus on the VAS 1-10. Results: In both groups an improvement in VAS was observed-in group I-in five ears (83.3%), in group II-in seven ears (58.3%). In Group I, a significant increase in the upper and lower limit frequency of alpha band was observed in the central temporal and frontal regions following ES. These changes, however, were not correlated with improvement in tinnitus. No significant changes were observed in the beta and theta bands and in group II. Preliminary results of our research reveal a change in cortical activity after electrical stimulations of the ear. However, it remains unclear if it is primary or secondary to peripheral auditory excitation. No similar studies had been found in the literature.

13.
Otolaryngol Pol ; 70(2): 19-24, 2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-27386829

RESUMO

INTRODUCTION: The aim of this work was to evaluate the correlation between Apnea/Hypopnea Index (AHI) and selected parameters of morphological and clinical character in the patients with a unilateral or bilateral impairment of nasal patency. MATERIAL AND METHODS: The study covered 60 adults, including 37 male and 23 female subjects, 19-69 years of age. In the Department, these subjects were divided into 3 groups: I - 20 patients with unilateral impairment of nasal patency, II - 20 patients with bilateral impairment of nasal patency, III - controls with normal nasal patency. METHODOLOGY: A subjective examination (questionnaire with a sleepiness scale), an objective examination (general examination of the neck and waist diameter, body weight, height, length of the uvula), otorhinolaryngological examination (Pirquet test of the palatine tonsils), X-ray and CT of the head and paranasal sinuses) to determine the cause and location of the obturation of air passages, physiological tests and polysomnography. The correlations between the neck circumferenceheight ratio (NHR) and AHI, waist-hip ratio (WHR) and AHI. The statistical analysis of the study results was conducted in Stata®/Special Edition Program, 14.1 version (StataCorp LP, College Station, Texas, USA). RESULTS: Clinically, the study group revealed: shallow breathing in 47.5% and apnea in 52.5% of the studied patients whereas the control group did not show any sleep disorders. Statistical fluctuations between controls and the study groups were noticed (p<0.001). CONCLUSION: By the Epworth scale, moderate and severe sleepiness was found in merely 12.5% of the patients. The differences in the length of the uvula and the size of the pharyngeal tonsils between the studied groups were not statistically significant. No statistical significance was found between NHR and AHI, BMI and AHI, WHR and AHI in the studied group.


Assuntos
Nariz/anormalidades , Nariz/anatomia & histologia , Tonsila Palatina/anormalidades , Tonsila Palatina/anatomia & histologia , Apneia Obstrutiva do Sono/etiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
14.
Otolaryngol Pol ; 70(2): 31-7, 2016 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-27386831

RESUMO

INTRODUCTION: The aim of this work was to describe the polysomnographic evaluation of sleep apnea in patients suffering from unilateral or bilateral impaired nasal passage patency. MATERIAL AND METHODS: The study covered 60 adult, including 23 women and 37 men aged 19-69, admitted to the Hospital Department. The subjects were divided into 3 groups: I - 20 patients with unilateral impaired nasal patency, II - 20 patients with bilateral impaired nasal patency, III - 20 controls with correct nasal passage patency. The methodology of the study included: a subjective examination, a questionnaire with questions about main night symptoms, e.g. dyspnea, noisy snoring, polynuria, an objective examination, blood tests (morphology, CRP, fibrinogen, IL-6, glucose level), imaging tests (RTG, CT and MRI of the head/paranasal sinuses) to determine the cause and site of respiratory obturation, physiological tests as a part of polysomnogram. The analysis described: the level of sleep disorders, causes associated with impaired nasal patency and the Mladina's classification of the nasal septum deviation. RESULTS: Due to the conducted polysomnogram and analysis of the additional tests, sleep apnea was diagnosed in the studied patients with impaired nasal patency: shallow breathing u 19 patients (47,5%) with unilateral impaired patency and 9 patients (22,5%) with bilateral impaired patency, whereas apnea in 21 patients (52,5%) with unilateral impaired patency and 11 patients (27,5%) with bilateral impaired patency. In both groups I and II, the impaired nasal passage patency was caused by nasal septum deviation in 18 cases (34%) and in 15 cases (28,3%), respectively. The control group did not show any sleep disorders in polysomnographic tests. Each patient from group I and II was referred for surgery to improve the nasal patency due to its cause. CONCLUSION: The conducted tests revealed shallow breathing in 47,5% of the studied patients whereas sleep apnea in 52,5% cases. The most frequent cause of impaired nasal patency was nasal septum deviation, which was found in 82,5% of the patients, including 45% with unilateral impaired patency and 37,5% with bilateral nasal patency.


Assuntos
Obstrução Nasal/patologia , Septo Nasal/patologia , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/etiologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução Nasal/diagnóstico , Otolaringologia/instrumentação , Ronco/diagnóstico , Ronco/etiologia , Adulto Jovem
15.
Chem Commun (Camb) ; 50(83): 12450-3, 2014 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-24980805

RESUMO

While Ru is a poor hydrogenation catalyst compared to Pt or Pd in the gas phase, it is efficient under aqueous phase conditions in the hydrogenation of ketones such as the conversion of levulinic acid into gamma-valerolactone. Combining DFT calculations and experiments, we demonstrate that water is responsible for the enhanced reactivity of Ru under those conditions.


Assuntos
Cetonas/química , Lactonas/química , Ácidos Levulínicos/química , Catálise , Hidrogenação , Modelos Moleculares , Água/química
16.
Mater Sci Eng C Mater Biol Appl ; 42: 529-37, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25063150

RESUMO

The work presents results of the studies performed on electropolishing of pure niobium in a bath that contained: sulphuric acid, hydrofluoric acid, ethylene glycol and acetanilide. After the electropolishing, the specimens were subjected to anodic passivation in a 1moldm(-3) phosphoric acid solution at various voltages. The surface morphology, thickness, roughness and chemical composition of the resulting oxide layers were analysed. Thusly prepared niobium samples were additionally investigated in terms of their corrosion resistance in Ringer's solution. The electropolished niobium surface was determined to be smooth and lustrous. The anodisation led to the growth of barrier-like oxide layers, which were enriched in phosphorus species.


Assuntos
Corrosão , Técnicas Eletroquímicas , Nióbio/química , Oxirredução , Ácidos Fosfóricos , Espectroscopia Fotoeletrônica , Propriedades de Superfície
17.
Mater Sci Eng C Mater Biol Appl ; 39: 259-72, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24863224

RESUMO

This paper reports on the surface modification of a Ti-15Mo alloy by plasma electrolytic oxidation (PEO). This process was carried out in solutions of 0.1M Ca(H2PO2)2 with various concentrations of tricalcium phosphate (Ca3(PO4)2), wollastonite (CaSiO3), or silica (SiO2) using voltages of up to 350V. The surface microstructure (SEM, cross-section of coating), roughness and chemical composition (energy-dispersive X-ray spectroscopy, thin layer X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy) of the porous oxide layers were investigated. The concentration of powder added to the solution changed the chemical composition and morphology of PEO coatings on the Ti-15Mo alloy surface. Calcium and phosphorous compounds were detected in the coatings formed on the substrate by the PEO process at 300V.


Assuntos
Ligas/química , Eletrólise/métodos , Oxirredução , Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis/química , Teste de Materiais/métodos , Espectroscopia Fotoeletrônica , Porosidade , Dióxido de Silício/química , Espectrometria por Raios X , Propriedades de Superfície , Suspensões , Difração de Raios X
18.
Otolaryngol Pol ; 65(5 Suppl): 98-101, 2011 Sep.
Artigo em Polonês | MEDLINE | ID: mdl-22000258

RESUMO

INTRODUCTION: The aim of the work was to analyse sudden deterioration of hearing and/or vertigo occurrence as an early symptom of posterior cranial fossa tumours. MATERIAL AND METHODS: Among 1.394 people who reported vertigo and hearing impairment and were hospitalised at the Department of Otolaryngology and Laryngological Oncology Military Teaching Hospital in Lodz within the years of 2007-2010 twenty-seven patients were analysed. This group included 19 women aged 20-80 (mean age 45.7 years) and 8 men aged 25-73 (mean age 54.0 years) who had posterior cranial fossa tumours diagnosed on the basis of MRI. Each patient underwent a detailed interview, otorhinolaryngological and otoneurological examinations, pure tone, speech and impedance audiometry, suprathreshold tests (SISI, TDT), tinnitus pitch and frequency evaluation, auditory brainstem response (ABR), complete videonystagmography. RESULTS: The studied material revealed: acoustic neuroma in 15 patients, cerebellar meningioma in 5 patients, cerebellar cyst in 4 patients and cerebellar angioma in 3 patients. Sudden vertigo was present in 27 patients, including mixed-type vertigo in 15 cases and central vertigo in 12 cases. In 19 patients dizziness was accompanied by tinnitus. In 22 patients hearing disorders were diagnosed in a form of: sensorineural hearing loss in 14 subjects, bilateral in 7 subjects, left-lateral in 5 subjects and right-lateral in 2 subjects respectively, as well as deafness in 8 patients, including left ear deafness in 5 cases, right ear deafness in 1 case and bilateral deafness in 2 cases (7.4%). CONCLUSIONS: The early phase diagnosis of a posterior cranial fossa tumour as a cause of sudden hearing deterioration and/or vertigo is very seldom and often accidental because GPs, also otolaryngologists, who follow routine and economy, are not used to referring given patients for complete and objective audiological, otoneurological and imaging diagnostics.


Assuntos
Neoplasias do Ventrículo Cerebral/complicações , Fossa Craniana Posterior/patologia , Perda Auditiva Neurossensorial/complicações , Índice de Gravidade de Doença , Vertigem/etiologia , Testes de Impedância Acústica/métodos , Adulto , Idoso , Limiar Auditivo , Neoplasias do Ventrículo Cerebral/diagnóstico , Feminino , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Zumbido/etiologia , Vertigem/diagnóstico , Adulto Jovem
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