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BACKGROUND: Panic Attacks (PAs) and Panic Disorder (PD) represent a heavy burden not only because of the difficulty in distinguishing them from other pathologies and in treating them appropriately but also because of their impact on public health worldwide. In Europe, PD constitutes one of the five most common mental disorders adversely affecting quality of life. STUDY DESIGN: The aim of this study is to evaluate the period prevalence of visits to the Emergency Departments of the University Hospital of Verona (North East of Italy) over the period between 2012-2016 because of symptoms of PAs or PD in order to quantify the burden of the disorder. METHODS: This study was carried out by retrospectively collecting data from the medical records of all the patients assessed at the Emergency Departments (EDs) of the Verona Hospital because of symptoms of PAs or PD over a 5-year period (1 January 2012 - 31 December 2016). The search words used in reviewing the medical records registered in the hospital discharge reports from the Gynecological, Pediatric and General Medicine Emergency Departments were: "Anxiety" and/or "Panic". A multiple logistic regression model was also created to evaluate the predictors of ED visits for PAs or PD over the period that was investigated. RESULTS: The study identified 3,771 cases of PAs or PD; 62.3% were females and 37.7% were males. The female-to-male ratio was 1.7:1. The mean age was 44 years (46 for the females and 41 for the males). The majority of the patients fell into two age categories: 30 to 39 (20.6%) and 40 to 49 (23.8%). The proportion of visits to the EDs for PAs or PD was approximately 20% per year, with an average of approximately 754 patients visiting the EDs every year. The period prevalence of accesses for PAs or PD over the five year period studied in the mean resident population (1.4%) and the mean visits to the EDs (2.5%) were calculated. Study results showed that the majority of the patients (80.9%) were referred to their general practitioner (GP) at the end of the assessment protocol at the EDs. According to the regression logistic model, the following variables were significant (p<0.05) risk factors for PAs or PD: being female vs. male (OR 1.899; 95% CI 1.785-2.020), being Italian vs. Foreigner (OR 1.292; 95% CI 1.174-1.421), having a white or green priority code at arrival (low urgency) vs. the other ones (OR 1.195; 95% CI 1.100-1.297), and being aged ≤42 years old (OR 1.091; 95% CI 1.024-1.161). CONCLUSION: The role of the GP is crucial in the management of PD and PAs. Given the difficulty of implementing primary and secondary prevention programs for these conditions, public health officials should make every effort to promote tertiary prevention in order to reduce the burden of the ailment and societal cost.
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Ansiedade/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Transtorno de Pânico/epidemiologia , Qualidade de Vida , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitais Universitários , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Adulto JovemRESUMO
INTRODUCTION: The consumption of energy drinks (ED) and ginseng by young people to enhance their mental and physical performance has become widespread. Reported side-effects of ED have raised doubts regarding their safety. This cross-sectional study investigates the phenomenon. METHODS: An anonymous questionnaire was administered to a representative sample of Verona university students. The resulting data were analyzed with Excel 2013, STATA 13 software. RESULTS: ED and ginseng consumption was reported by 38.6% and 37.4% of the students, respectively. More than 70% of ED and ginseng users were 18 to 22 years old. Excluding non-responders, ED consumers were mostly males (51.8% vs 33.0%), contrary to ginseng consumers (females 40.4% vs 30.9%). Being a working student was significantly positively associated both to EDs (OR 1.5) and ginseng use (OR 1.4). The most frequently reported academic and other reasons for ED use were: "to study longer" (47.5%), and "to socialize" (29.1%). The most often used combinations were ED containing alcohol (65.6%) and ginseng-coffee beverages (71.8%). CONCLUSIONS: The diffusion of ED and ginseng consumption warrants prevention and monitoring measures, and deserves further analysis.
Assuntos
Bebidas Energéticas/estatística & dados numéricos , Panax , Instituições Acadêmicas , Estudantes , Adolescente , Estudos Transversais , Feminino , Humanos , Itália , Masculino , Inquéritos e QuestionáriosRESUMO
The aim of this work was to investigate the structural features of type I collagen isoforms and collagen-based films at atomic and molecular scales, in order to evaluate whether and to what extent different protocols of slurry synthesis may change the protein structure and the final properties of the developed scaffolds. Wide Angle X-ray Scattering data on raw materials demonstrated the preferential orientation of collagen molecules in equine tendon-derived collagens, while randomly oriented molecules were found in bovine skin collagens, together with a lower crystalline degree, analyzed by the assessment of FWHM (Full Width at Half Maximum), and a certain degree of salt contamination. WAXS and FT-IR (Fourier Transform Infrared) analyses on bovine collagen-based films, showed that mechanical homogenization of slurry in acidic solution was the treatment ensuring a high content of super-organization of collagen into triple helices and a high crystalline domain into the material. In vitro tests on rat Schwannoma cells showed that Schwann cell differentiation into myelinating cells was dependent on the specific collagen film being used, and was found to be stimulated in case of homogenization-treated samples. Finally DHT/EDC crosslinking treatment was shown to affect mechanical stiffness of films depending on collagen source and processing conditions.
Assuntos
Colágeno Tipo I/química , Células de Schwann/citologia , Pele/citologia , Tendões/citologia , Alicerces Teciduais/química , Animais , Bovinos , Células Cultivadas , Cavalos , Humanos , Teste de Materiais , Ratos , Medicina Regenerativa , Espalhamento de Radiação , Células de Schwann/química , Pele/química , Tendões/química , Resistência à Tração , Engenharia Tecidual/métodosRESUMO
This study evaluated a tendon substitute model. Tenocytes were isolated from pig Achilles tendon, seeded onto scaffolds (Opocrin 2%, Typeone 3% and Symatese 2%) and studied by histology, immunofluorescence for collagen type 1 and 3 and biochemical analysis to assess cellularity. The permeability of these compounds was evaluated in the presence or absence of fibrin glue. Opocrin 2% was the best choice for cellular distribution within the scaffolds, which were then cultured for T0, T4, T7 and T10 days. Fibrin glue has been strongly supportive for the survival of cells with a significant increase in DNA content at T10 (P<0.05). Moreover, the synthetic activity of fibrin-free scaffolds was always negative. Lastly, a progressive increase in collagen 1 and 3 with fibrin-glue was observed. However, static culture is not sufficient to support long-term cellular activities and at T10 there is still a lack of organized matrix similar to the native tissue.
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INTRODUCTION: The non-medical use of prescription stimulants (NMUPS) has become the subject of great interest for its diffusion among university students, who abuse these substances to cope with the increasing load of academic stress. NMUPS has been widely investigated in the U.S. due to its increasing trend; this behavior, however, has also been reported in Europe. The aim of this cross-sectional study was to examine stimulants misuse in a Northern Italian geographic area, identifying possible developments of the phenomenon in Italy. METHODS: To evaluate academic and extra-academic NMUPS (Methylphenidate and Amphetamines), an anonymous multiplechoice questionnaire was administrated to a sample of Bachelor's and Master's degrees students attending a University North East of Italy. Data elaboration and CI 95% were performed with Excel software 2013. Fisher's exact tests were performed using Graph- Pad INSTAT software. RESULTS: Data from 899 correctly completed questionnaires were analyzed in this study. 11.3% of students reported NMUPS, with an apparent greater use by students aged 18-22 years (73.5%) and without any statistically significant gender predominance. Fifty-seven point eight percent of students used stimulants at most five times in six months, and the most frequent academic and extra-academic reasons to use them were respectively to improve concentration while studying (51.0%) and sports performance (25.5%). NMUPS was higher among working students than nonworking ones (p < 0.05), suggesting a use of stimulants to cope with stress by the first ones. CONCLUSIONS: These exploratory and preliminary data suggest that NMUPS is quite relevant in Northern Italy, suggesting a need for preventive and monitoring measures, as well as future analysis via a longitudinal multicenter study.
Assuntos
Estimulantes do Sistema Nervoso Central/administração & dosagem , Uso Indevido de Medicamentos sob Prescrição/estatística & dados numéricos , Estudantes/psicologia , Logro , Adolescente , Feminino , Humanos , Itália , Masculino , Inquéritos e Questionários , Universidades , Adulto JovemRESUMO
In the last years, several tissue engineering techniques have been applied to develop different kinds of osteochondral substitutes to overcome the scarce reparative properties of this tissue. The aim of this study was to generate and compare three biphasic scaffolds in an osteochondral lesion in a large-animal model. A critical osteochondral defect was generated in the medial femoral condyle of 18 skeletally mature sheep. Three defects were left untreated, the remaining lesions were divided into three groups: 5 lesions were treated with a biphasic scaffold made of collagen type I and small cylinders of Magnesium Hydroxyapatite; 5 lesions were treated with a biphasic substituted formed by collagen type I and Wollastonite, 5 lesions were treated with a scaffold made of collagen type I and small cylinders of Wollastonite/Hydroxyapatite. Animals were sacrificed after 3 months and samples were analyzed by CT and MRI, macroscopic evaluation and histology. Our study demonstrated that one of these novel biphasic scaffolds possesses the potential for being applied for one-stage procedures for osteochondral defects.
Assuntos
Doenças Ósseas/patologia , Doenças Ósseas/terapia , Condrócitos/patologia , Osteócitos/patologia , Ovinos , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Colágeno Tipo I/química , Modelos Animais de Doenças , Durapatita/química , Fêmur/patologiaRESUMO
Cell-cell interactions promote juxtacrine signals in specific subcellular domains, which are difficult to capture in the complexity of the nervous system. For example, contact between axons and Schwann cells triggers signals required for radial sorting and myelination. Failure in this interaction causes dysmyelination and axonal degeneration. Despite its importance, few molecules at the axo-glial surface are known. To identify novel molecules in axo-glial interactions, we modified the 'pseudopodia' sub-fractionation system and isolated the projections that glia extend when they receive juxtacrine signals from axons. By proteomics we identified the signalling networks present at the glial-leading edge, and novel proteins, including members of the Prohibitin family. Glial-specific deletion of Prohibitin-2 in mice impairs axo-glial interactions and myelination. We thus validate a novel method to model morphogenesis and juxtacrine signalling, provide insights into the molecular organization of the axo-glial contact, and identify a novel class of molecules in myelination.
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Axônios/metabolismo , Bainha de Mielina/metabolismo , Comunicação Parácrina , Pseudópodes/metabolismo , Proteínas Repressoras/metabolismo , Células de Schwann/metabolismo , Animais , Western Blotting , Imunofluorescência , Gânglios Espinais/citologia , Imuno-Histoquímica , Camundongos , Células NIH 3T3 , Neuroglia/metabolismo , Proibitinas , Proteômica , RatosRESUMO
Silver nanophases are increasingly used as effective antibacterial agent for biomedical applications and wound healing. This work aims to investigate the surface chemical composition and biological properties of silver nanoparticle-modified flax substrates. Silver coatings were deposited on textiles through the in situ photo-reduction of a silver solution, by means of a large-scale apparatus. The silver-coated materials were characterized through X-ray Photoelectron Spectroscopy (XPS), to assess the surface elemental composition of the coatings, and the chemical speciation of both the substrate and the antibacterial nanophases. A detailed investigation of XPS high resolution regions outlined that silver is mainly present on nanophases' surface as Ag2O. Scanning electron microscopy and energy dispersive X-ray spectroscopy were also carried out, in order to visualize the distribution of silver particles on the fibers. The materials were also characterized from a biological point of view in terms of antibacterial capability and cytotoxicity. Agar diffusion tests and bacterial enumeration tests were performed on Gram positive and Gram negative bacteria, namely Staphylococcus aureus and Escherichia coli. In vitro cytotoxicity tests were performed through the extract method on murine fibroblasts in order to verify if the presence of the silver coating affected the cellular viability and proliferation. Durability of the coating was also assessed, thus confirming the successful scaling up of the process, which will be therefore available for large-scale production.
Assuntos
Antibacterianos/farmacologia , Prata/química , Animais , Antibacterianos/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/efeitos adversos , Camundongos , Espectroscopia Fotoeletrônica , Staphylococcus aureus/efeitos dos fármacosRESUMO
Understanding the relationships between material surface properties and cellular responses is essential to designing optimal material surfaces for implantation and tissue engineering. In this study, cellulose hydrogels were crosslinked using a non-toxic and natural component namely citric acid. The chemical treatment induces COOH functional groups that improve the hydrophilicity, roughness, and materials rheological properties. The physiochemical, morphological, and mechanical analyses were performed to analyze the material surface before and after crosslinking. This approach would help determine if the effect of chemical treatment on cellulose hydrogel improves the hydrophilicity, roughness, and rheological properties of the scaffold. In this study, it was demonstrated that the biological responses of human mesenchymal stem cell with regard to cell adhesion, proliferation, and differentiation were influenced in vitro by changing the surface chemistry and roughness.
Assuntos
Diferenciação Celular/efeitos dos fármacos , Ácido Cítrico/farmacologia , Reagentes de Ligações Cruzadas/farmacologia , Hidrogéis/farmacologia , Osteogênese/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Biomarcadores/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Celulose/química , Celulose/farmacologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Microscopia de Força Atômica , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Transcrição Gênica/efeitos dos fármacos , Viscosidade , Água/químicaRESUMO
The infections give rise to a range of clinical problems and prolong hospitalization with increased healthcare costs. Moreover, persistent infections exasperate the problem of antibiotic resistance. The aim of this study was the development of effective and low-cost antibacterial silver coatings on surgical sutures by adopting an innovative photochemical deposition process to prevent early contamination of surgical wounds. The silver deposition technology adopted in this work is an innovative process based on the in situ photoreduction of a silver solution. The samples were dipped in the silver solution and then exposed to UV radiation in order to induce the synthesis of silver clusters on the surface of the suture. The homogeneous distribution of silver particles on the surface and on the cross-section of the treated sutures was demonstrated. All the antibacterial studies clearly demonstrated that the use of novel silver treated sutures could represent clinical advantages in terms of the prevention of surgical infections against bacterial colonization. The silver coating deposited on the sutures demonstrated no cytotoxic effect on a selected cell population. The results obtained suggested that the antibacterial silver-coated sutures developed in this work could represent an interesting alternative to conventional sutures, with evident advantages in terms of prevention of the surgical infections and on the health costs. In addiction, very low concentrations of silver significantly inhibited the microbial load, without affecting the cell viability.
Assuntos
Materiais Revestidos Biocompatíveis , Nanopartículas Metálicas , Seda , Prata/química , Infecção da Ferida Cirúrgica/prevenção & controle , Suturas/efeitos adversos , Células 3T3 , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Contagem de Colônia Microbiana , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Camundongos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Resistência à TraçãoRESUMO
The microstructural, mechanical, compositional, and degradative properties of a nerve conduit are known to strongly affect the regenerative process of the injured peripheral nerve. Starting from the fabrication of micropatterned collagen-based nerve guides, according to a spin-casting process reported in the literature, this study further investigates the possibility to modulate the degradation rate of the scaffolds over a wide time frame, in an attempt to match different rates of nerve regeneration that might be encountered in vivo. To this aim, three different crosslinking methods, that is, dehydrothermal (DHT), carbodiimide-based (EDAC), and glutaraldehyde-based (GTA) crosslinking, were selected. The elastically effective degree of crosslinking, attained by each method and evaluated according to the classical rubber elasticity theory, was found to significantly tune the in vitro half-life (t1/2 ) of the matrices, with an exponential dependence of the latter on the crosslink density. The high crosslinking efficacy of EDAC and GTA treatments, respectively threefold and fourfold when compared to the one attained by DHT, led to a sharp increase of the corresponding in vitro half-lives (ca., 10, 172, and 690 h, for DHT, EDAC, and GTA treated matrices, respectively). As shown by cell viability assays, the cytocompatibility of both DHT and EDAC treatments, as opposed to the toxicity of GTA, suggests that such methods are suitable to crosslink collagen-based scaffolds conceived for clinical use. In particular, nerve guides with expected high residence times in vivo might be produced by finely controlling the biocompatible reaction(s) adopted for crosslinking.
Assuntos
Materiais Biocompatíveis/química , Colágeno/química , Regeneração Tecidual Guiada/métodos , Nervos Periféricos , Alicerces Teciduais/química , Células 3T3 , Animais , Carbodi-Imidas/química , Reagentes de Ligações Cruzadas/química , Glutaral/química , CamundongosRESUMO
Textiles are a fertile breeding ground for a multitude of micro-organisms under appropriate conditions of moisture and temperature. The broad-spectrum biocide properties of silver are well known and many technologies have been developed so far to treat textiles with silver. The efficacy of the silver deposition technology presented in this article has been already demonstrated in previous works, where the strong adhesion of silver nanoparticles to the substrate and their antibacterial capability have been assessed. This work focuses on the evaluation of any possible interaction of silver treated cotton with human skin, in terms of skin irritation and hypoallergenicity. Moreover, the presence of silver and the antibacterial capability against Gram positive and Gram negative bacteria, namely Staphylococcus aureus and Escherichia coli, were verified even after several washing cycles in order to develop a product with long-term antibacterial capability and no adverse effects in terms of skin irritation and hypoallergenicity.
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Antibacterianos , Materiais Revestidos Biocompatíveis , Fibra de Algodão , Nanopartículas Metálicas/química , Testes de Irritação da Pele , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Escherichia coli/crescimento & desenvolvimento , Feminino , Humanos , Masculino , Prata , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
The onset of infections associated to bacterial proliferation and biofilm formation on indwelling medical devices represents the major risk of morbidity and mortality among patients. In order to contain the risk of infections in clinical practice, there is a growing interest nowadays in silver-based products due to the strong antimicrobial efficacy of silver against a broad spectrum of microorganisms. In this work, temporary catheters for haemodialysis were coated with silver nano-particles through the in situ photo-reduction of a silver salt in alcoholic solution. A homogeneous distribution of silver particles firmly bonded to the substrate was obtained through the adopted technique. An optimisation study was required to define the amount of silver, in order to obtain good efficacy against Gram-positive and Gram-negative bacteria and no cytotoxic effect. At this purpose, three concentrations of silver, 0.1, 0.25 and 0.5 wt%, have been deposited and tested with respect to bacterial reduction percentage and cellular response. Particularly, bacterial enumeration on Escherichia coli and Staphylococcus aureus, and BrdU incorporation, TUNEL assay and Actin staining on a selected primary cell population were performed on catheters treated with the different silver solutions. The silver percentages tested demonstrated strong antibacterial properties together with a good cellular response, thus indicating that the developed product could be proposed in clinical practice and that the lower percentage tested can be preferred with evident advantages in terms of costs.
Assuntos
Antibacterianos/farmacologia , Cateteres de Demora , Proliferação de Células , Nanopartículas Metálicas , Diálise Renal , Prata/química , Animais , Apoptose , Células Cultivadas , Marcação In Situ das Extremidades Cortadas , Poliuretanos/química , SuínosRESUMO
The growing resistance of many strains of bacteria to antibiotics and antiseptics is becoming a serious problem in medicine. Nano-silver is one of the most prominent products in medicine because it exhibits unusual physicochemical properties and a strong biological activity. In this work an innovative silver deposition technology was applied to temporary polyurethane catheters for haemodialysis. The working conditions of catheters were reproduced through laboratory equipment that ensured the flow of deionized water and simulated body fluid inside the lumina at corporeal temperature. The growth and the adhesion of Staphylococcus aureus on the surface of the device were studied through fluorescence microscopy. ICP-AES was adopted to calculate the amount of silver released from the substrate. The stability of the coating during the whole working life of the device was demonstrated through thermo-gravimetric analysis.
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Aderência Bacteriana/efeitos dos fármacos , Infecções Relacionadas a Cateter/prevenção & controle , Cateterismo Venoso Central/instrumentação , Materiais Revestidos Biocompatíveis/administração & dosagem , Materiais Revestidos Biocompatíveis/química , Diálise Renal/instrumentação , Prata/administração & dosagem , Antibacterianos/administração & dosagem , Antibacterianos/química , Infecções Relacionadas a Cateter/etiologia , Infecções Relacionadas a Cateter/microbiologia , Cateterismo Venoso Central/efeitos adversos , Humanos , Teste de Materiais , Diálise Renal/efeitos adversos , Prata/químicaRESUMO
Antibacterial coatings on catheters for acute dialysis were obtained by an innovative and patented silver deposition technique based on the photo-reduction of the silver solution on the surface of catheter, with consequent formation of antibacterial silver nanoparticles. Aim of this work is the structural and morphological characterization of these medical devices in order to analyze the distribution and the size of clusters on the polymeric surface, and to verify the antibacterial capability of the devices treated by this technique against bacterial proliferation. The structure and morphology of the silver nanoparticles were investigated by using scanning and transmission electron microscopy. The antimicrobial capability of the catheters after silver deposition was confirmed by antibacterial tests with Escherichia coli. Both scanning electron microscopy analysis and antibacterial tests were performed also after washing catheters for 30 days in deionized water at 37°C, relating these data to thermogravimetric analysis and to energy dispersive spectroscopy, in order to check the resistance of coating and its antimicrobial capability after the maximum time of life of these devices.
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Antibacterianos , Catéteres , Nanopartículas Metálicas , Diálise Renal , Prata , Escherichia coli/efeitos dos fármacos , Microscopia Eletrônica de VarreduraRESUMO
The aim of this study was to investigate DNA damage in human dermal fibroblasts from a healthy subject and from a subject affected by Turner's syndrome that were exposed for 24 h to radiofrequency (RF) radiation at 900 MHz. The RF-radiation exposure was carried out alone or in combination with 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a well-known environmental mutagen and carcinogen produced during the chlorination of drinking water. Turner's syndrome fibroblasts were also exposed for a shorter time (1 h). A signal similar to that emitted by Global System for Mobile Communications (GSM) mobile phones was used at a specific absorption rate of 1 W/kg under strictly controlled conditions of temperature and dosimetry. To evaluate DNA damage after RF-radiation exposure alone, the alkaline comet assay and the cytokinesis-block micronucleus assay were used. In the combined-exposure experiments, MX was given at a concentration of 25 microM for 1 h immediately after the RF-radiation exposure, and the effects were evaluated by the alkaline comet assay. The results revealed no genotoxic and cytotoxic effects from RF radiation alone in either cell line. As expected, MX treatment induced an increase in DNA migration in the comet assay, but no enhancement of the MX-induced DNA damage was observed in the cells exposed to RF radiation.
Assuntos
Dano ao DNA , DNA/efeitos da radiação , Fibroblastos/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Furanos/toxicidade , Mutagênicos/toxicidade , Ondas de Rádio/efeitos adversos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Ensaio Cometa , DNA/efeitos dos fármacos , Humanos , Testes para Micronúcleos , Temperatura , Síndrome de Turner/genética , Síndrome de Turner/patologiaRESUMO
Surface treatments of textile fibers and fabrics significantly increase their performances for specific biomedical applications. Nowadays, silver is the most used antibacterial agent with a number of advantages. Among them, it is worth to note the high degree of biocompatibility, an excellent resistance to sterilization conditions, antibacterial properties with respect to different bacteria associated with a long-term of antibacterial efficiency. However, there are only a few antibacterial fibres available, mainly synthetic with high production cost and limited effectiveness. Cotton yarns with antimicrobial properties are most suitable for wound healing applications and other medical treatments thanks to their excellent moisture absorbance while synthetic based fibres are most suitable for industrial applications such as automotive tapestry and air filters. The silver-coated fibers were developed applying an innovative and low cost silver deposition technique for natural and synthetic fibers or yarns. The structure and morphology of the silver nanoclusters on the fibers was observed by scanning electron microscopy (SEM), atomic force microscopy analysis (AFM) and XRD analysis, and quantitatively confirmed by thermogravimetric analysis (TGA) measurements. Good silver coating stability has been confirmed performing several industrial washing. Antimicrobial tests with Escherichia coli were performed.
Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Prata/química , Têxteis , Cristalização , Escherichia coli/metabolismo , Imageamento Tridimensional , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Varredura/métodos , Poliésteres/química , Propriedades de Superfície , Termogravimetria/métodos , Fatores de Tempo , Cicatrização , Difração de Raios XRESUMO
The stiffness as well as the biodegradation rate of collagen and gelatine products can be modulated by performing a number of crosslinking treatments. In many biomedical applications, an optimal degree of crosslinking seems to exist, depending on the mechanical and/or biosynthesis properties of the host site. The aim of this study was to evaluate the optimal degree of crosslinking of collagen and gelatine films, to be used as sealants for vascular prostheses. Various crosslinking treatments, including exposure to aldehydes, dehydrothemal treatment, carbodiimide crosslinking and combinations of them, were performed on collagen and gelatine films, and the resulting increases in stiffness, degree of crosslinking and denaturation temperature were evaluated. Analogue crosslinking treatments were also performed on sealed prostheses, which were then tested for blood leakage. The experimental results showed that a good blood impermeability of both collagen and gelatine films was obtained for crosslinking density of about 1.2-1.3 x 10(-5) mol/cm(3), which could be yielded by a dehydrothermal crosslinking treatment (DHT). In particular, dehydrothermally treated gelatine-coated prostheses were found to perform better than analogue collagen-coated ones. The presence of glycerol in crosslinked collagen films was found to have plasticizing effects, which are likely to facilitate blood impermeability, and to increase the thermal stability of collagen.
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Prótese Vascular , Permeabilidade Capilar/efeitos dos fármacos , Colágeno/farmacologia , Gelatina/farmacologia , Membranas Artificiais , Fenômenos Biomecânicos , Sangue/metabolismo , Implante de Prótese Vascular/instrumentação , Carbodi-Imidas/farmacologia , Colágeno/síntese química , Colágeno/química , Colágeno/farmacocinética , Reagentes de Ligações Cruzadas/química , Reagentes de Ligações Cruzadas/farmacologia , Cianamida/farmacologia , Formaldeído/farmacologia , Gelatina/síntese química , Gelatina/química , Gelatina/farmacocinética , Temperatura Alta , Humanos , Teste de MateriaisRESUMO
A method based on gas chromatography/tandem mass spectrometry was used to assess levels of twelve phthalates in 50 samples of oily foods packed in glass jars with metal closure obtained from a retail market. The amounts of di-methyl phthalate, di-ethyl phthalate, di-propyl phthalate, di-butyl phthalate, di-pentyl phthalate, benzyl butyl phthalate, di-cyclohexyl phthalate, di-n-octyl phthalate, di-isononyl phthalate and di-isodecyl phthalate in all samples analysed were less than the limit of quantification (LOQ). Di-(2-ethylhexyl) phthalate was detected in 20 samples in the range from 0.1 to 6 mg kg(-1) with an average of 1.0 mg kg(-1), and it exceeded the specific migration limit (SML) of 1.5 mg kg(-1) in five cases with an average of 3.0 mg kg(-1). Di-isobutyl phthalate was found in four samples at 0.1-0.4 mg kg(-1). The PVC gaskets used for the lids were negative for all tested phthalates, suggesting that the contamination of the foods originated from other sources, e.g. olive oil.
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Contaminação de Alimentos/análise , Vidro , Ácidos Ftálicos/análise , Cloreto de Polivinila , Cromatografia Gasosa-Espectrometria de Massas , Itália , Limite de Detecção , Controle de QualidadeRESUMO
In this study, the induction of apoptosis after exposure to 900 MHz radiofrequency radiation (GSM signal) was investigated by assessing caspase 3 activation in exponentially growing Jurkat cells and in quiescent and proliferating human peripheral blood lymphocytes (PBLs). The exposure was carried out at an average specific absorption rate of 1.35 W/kg in a dual wire patch cell exposure system where the temperature of cell cultures was accurately controlled. After 1 h exposure to the radiofrequency field, a slight but statistically significant increase in caspase 3 activity, measured 6 h after exposure, was observed in Jurkat cells (32.4%) and in proliferating human PBLs (22%). In contrast, no effect was detected in quiescent human PBLs. In the same experimental conditions, apoptosis was also evaluated in Jurkat cells by Western blot analysis and in both cell types by flow cytometry. To evaluate late effects due to caspase 3 activity, flow cytometry was also employed to assess apoptosis and viability 24 h after radiofrequency-radiation exposure in both cell types. Neither the former nor the latter was affected. Since in recent years it has been reported that caspases are also involved in processes other than apoptosis, additional cell cycle studies were carried out on proliferating T cells exposed to radiofrequency radiation; however, we found no differences between sham-exposed and exposed cultures. Further studies are warranted to investigate the biological significance of our findings of a dose-response increase in caspase 3 activity after exposure to radiofrequency radiation.