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PURPOSE: To evaluate the performance of a rapid multiplex microarray-based method (Unyvero BCU system, BCU) to identify microorganisms and detect antimicrobial resistance directly from positive blood culture (BC) bottles with polymicrobial growth, and to assess relevance of information provided for timely guidance of polymicrobial bloodstream infection treatment. METHODS: Accuracy, time-to-actionable results and potential impact of BCU on antimicrobial treatment were compared with those of standard of care during a prospective study for the sample analysis (November 2017-November 2018) and a retrospective study for the clinical data analysis and the time-to-result analysis. The study was complemented with an experimental study, based on spiked blood cultures to assess the ability of the method to detect antimicrobial resistance genes. RESULTS: Sixty-five clinical polymicrobial BC samples (163 total microorganisms) and 30 simulated polymicrobial BC samples (60 strains) were included. BCU reported 84.6% samples as polymicrobial, correctly identified all the bacteria of the mix for 72.3% samples (47/65) and detected bacteria that were missed by the conventional culture for 13.8% samples. All identifications and antimicrobial resistances were accurately detected for 61.5% (40/65) samples. Limitations concerned the detection of anaerobes, enterococci and enterobacterial susceptibility to third generation cephalosporins. BCU results would have guided antimicrobial treatment for 50.8% of the cases (33/65) in a timely and relevant manner, had no impact for 27.7% (18/65) and been misleading for 18.5% (12/65). CONCLUSIONS: Despite some limitations, the Unyvero BCU system is a rapid and reliable method for polymicrobial BC sample analysis.
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Bacteriemia , Bactérias , Hemocultura , Coinfecção , Reação em Cadeia da Polimerase Multiplex , Humanos , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Bacteriemia/diagnóstico , Coinfecção/tratamento farmacológico , Coinfecção/microbiologia , Estudos Retrospectivos , Estudos Prospectivos , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/classificação , Reação em Cadeia da Polimerase Multiplex/métodos , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana , Masculino , Feminino , Pessoa de Meia-Idade , IdosoRESUMO
We present a study of Yb:YAG active media slabs, based on a ceramic layered structure with different doping levels. We developed a procedure allowing 3D numerical analysis of the slab optical properties as a consequence of the thermal load induced by the pump process. The simulations are compared with a set of experimental results in order to validate the procedure. These structured ceramics appear promising in appropriate geometrical configurations, and thus are intended to be applied in the construction of High Energy Diode Pumped Solid State Laser (DPSSL) systems working in high repetition-rate pulsed regimes.
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In this paper we report on a computationally cost-effective method designed to estimate the thermal conductivity of optical materials based on cubic oxide including mixed ones, i.e. solid solutions of different oxides. The proposed methodology take advantage from Density Functional Theory (DFT) calculations to extract essential structural parameters and elastic constants which represent the inputs for revised versions of Slack and Klemens equations relating thermal conductivity to elastic constants. Slack equation is modified by the introduction of a corrective factor that incorporates the Grüneisen parameter γ, while in the revised Klemens equation a distortion parameter d accounting for the impact of point defects on lattice symmetry is added, which is a critical factor in determining thermal conductivity in optical materials with mixed compositions. The theoretical results were found in good agreement with experimental data, showing the reliability of our proposed methodology.
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United Nations' Agenda 2030 highlights the need to "make cities and human settlements inclusive, safe, resilient and sustainable" (SDG 11) and reduce inequalities (SDG 10) for the good health and well-being (SDG 3) of the citizens. Although most Italian museums have been forced to comply with the rules for accessibility in public spaces since 1971 following Law 30/3/1971 n. 118 and, more recently, Legislative Decree 81/2008, in this context, Universal Design can contribute to the achievement of these goals by improving accessibility to spaces, services, and the community's well-being on the one hand, along with providing a deeper comprehension and awareness of the informational processes on the other hand. In this regard, museum organizations play a critical role in enhancing the quality of life and society's education by preserving and distributing cultural heritage over time. Despite the large number of studies focused on museum organizations, there is little research that takes into account Universal Design and its macro-and firm-level economic benefits on museum institutions (not-for-profit, public, and private). Considering this research gap, this study's aim is twofold: 1) to explore how some Italian museums have actually improved their facilities and services according to Universal Design principles and 2) to assess the economic museum accessibility. A qualitative methodology was applied using a questionnaire delivered to eight Italian museum, and collected data was compared. The findings underline how museums' investments in Universal Design may produce relevant economic benefits, both on the macroeconomic and firm levels, providing guidelines for public policies concerning welfare, transport, environment, education, and well-being. Universal Design principles can lead museums to an increasing convergence toward Sustainable Development Goals, improving their overall economic performance as well as strengthening their role in a more aware and participative society. This study has several relevant implications in terms of both policy and management. Policymakers should promote Universal Design investments in museums in order to ensure accessibility to a greater number of visitors, and cultural institutions should consider accessibility as a specific key management dimension to be monitored and improved.
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Desenvolvimento Sustentável , Desenho Universal , Humanos , Museus , Qualidade de Vida , Nações UnidasRESUMO
OBJECTIVES: The aim of this study was to investigate the epidemiology of candidemia, the fungal susceptibility, the first-line therapy and the morality rate over 5 years. Knowing the differences of the yeasts in the candidemia local epidemiology, is essential to obtain information on fungal epidemiology to adapt antifungal strategies. MATERIALS/METHODS: This retrospective study was conducted from January 2014 to December 2018. The susceptibility of the Candida strains were tested for amphotericin B, caspofungin, voriconazole and fluconazole. RESULTS: The 304 strains were isolated from 290 patients (40 patients in 2014, 65 in 2015, 72 in 2016, 62 in 2017 and 51 in 2018). The three most common Candida spp isolated from blood cultures were Candida albicans (44%), Candida glabrata (22%) and Candida parapsilosis (13%). The proportion of non-albicans Candida decreased from 68% in 2014 to 45% in 2018. C. albicans and C. parapsilosis were to the four antifungals tested. As first-line therapy, 60% of patients received caspofungin and 26% fluconazole. There was no significant difference in the mortality between the two arms of patients (, 27% and 21%, p = 0.47 at 30 days respectively). Thirty day all-cause mortality was 31% and it decreased from 2014 (46%) to 2018 (18%). CONCLUSIONS: We report that the absence of antifungal resistance of our C. albicans and C. parapsilosis candidemia suggests possible treatment after MALDI-TOF identification with fluconazole as first-line therapy in our hospital, as soon as possible and while continuing to perform the antifungal test.
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Antifúngicos , Candidemia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Candidemia/tratamento farmacológico , Candidemia/epidemiologia , Farmacorresistência Fúngica , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Estudos RetrospectivosRESUMO
We present an experimental technique that allows the direct measurement of the continuous wave (cw) lasing threshold and the slope efficiency of a Ce:LiCaAlF6 (Ce:LiCAF) laser source by means of time-resolved measurement in the pulsed regime. We used a long-pulse-duration source to pump a tunable laser and a high-efficiency nondispersive laser in a quasi-stationary lasing regime. We compare the experimental results with earlier theoretical evaluations, and we demonstrate the feasibility of a cw Ce:LiCAF laser. Under the conditions discussed here, our technique can be applied to all the active media that achieved pulsed laser emission to investigate their potential as cw laser active media.
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Warfarin is employed more frequently than acenocoumarol because of its longer half-life (36 h), theoretically providing more stable anticoagulation, and avoiding factor VII fluctuations that potentially occur during acenocoumarol treatment (half-life 10 h). The aim of our study was to compare acenocoumarol with warfarin in the same group of 103 patients who started oral anticoagulation with acenocoumarol and then changed to warfarin. In these patients we compared the previous period of six months on acenocoumarol treatment (July-December 1996) with a new six-month period on warfarin (July-December 1997). We wished to know whether warfarin could improve the quality and the stability of oral anticoagulation of our patients and whether there was a difference between the two drugs in the weekly mean dose per patient. Moreover in order to detect the possible daily fluctuation of factor VII, we evaluated a further group of 54 patients. A subgroup of these patients was treated with warfarin while another received acenocoumarol. In the first group of patients, 1,158 and 1,064 PTs were carried out with acenocoumarol and warfarin, respectively. The percentage of PTs in the therapeutic range was 59% with acenocoumarol and 62% with warfarin (p=0.4). The mean number of visits per patient was 12 and 11, and the mean number of visits in the therapeutic range was 7 and 7, respectively. The last check in file method did not show any difference between the two drugs. Overdose states were 51 (4.4%) with acenocoumarol and 30 (2.8%) with warfarin (p=0.4). A good correlation (r=0.92) was found between the acenocoumarol and the warfarin weekly mean dose. The mean warfarin/acenocoumarol weekly dose ratio was 2.08 (range: 1.25-3.30; CI 95%: 1.99-2.16). In the second group of patients, factor VII levels with both drugs were higher 24 h after administration than 16 h after, showing that their daily fluctuation was independent of the drug's half-life, since factor VII levels in patients with a low vitamin K intake were not increased. Our results showed that warfarin did not appear to be better than acenocoumarol in the performance of an Anticoagulation Clinic in terms of PTs within the therapeutic range per patient. It seems that the behaviour of factor VII was affected by the intake of vitamin K rather than by the short half-life of acenocoumarol.
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Acenocumarol/uso terapêutico , Anticoagulantes/uso terapêutico , Trombofilia/tratamento farmacológico , Varfarina/uso terapêutico , Acenocumarol/administração & dosagem , Acenocumarol/efeitos adversos , Administração Oral , Adulto , Idoso , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Estudos Cross-Over , Relação Dose-Resposta a Droga , Fator VII/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Protrombina , Resultado do Tratamento , Vitamina K/farmacologia , Varfarina/administração & dosagem , Varfarina/efeitos adversosRESUMO
The aim of this study was to compare recombinant thromboplastin (rTF, ISI = 0.82) with rabbit thromboplastin (RT, ISI = 1.46) in order to evaluate which performed better in our thrombosis centre. To this purpose we randomized 67 patients to be double-blind monitored in two groups for three months either with PT performed with RT or with PT performed with rTF. After this period each patient was shifted to the other group. We considered the following as end points of the study: percentages of PT results within the therapeutic range, number of visits and therapeutic dose adjustments per patient. The "last check in file" method was used to evaluate the laboratory quality of oral anticoagulation for both thromboplastins. The results show that there was no difference in the number of visits per patient between the two groups: 6.9 +/- 1.7 in the rTF group versus 7.3 +/- 1.9 in the RT group (p = 0.19). The variations of therapeutic dose per patient were not different in the two groups: the dose was changed once (range 0-8) in the rTF group and once (range 0-11) in the RT group (p = 0.15). The percentages of PT results within the therapeutic range were not different between the two groups. The "last check in file" method showed similar percentages in both groups: PT results in the therapeutic range were 67.2% in the RT group and 68.8% in the rTF group. We conclude that the two thromboplastins had a similar effect on the end points of the study in spite of the relatively high ISI of the RT.
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Anticoagulantes/uso terapêutico , Tromboplastina/uso terapêutico , Administração Oral , Adulto , Idoso , Animais , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Coelhos , Proteínas Recombinantes/uso terapêuticoRESUMO
The development of gamma-glutamyltranspeptidase (GGT)-positive foci, in Wistar rats, initiated with diethylnitrosamine and subjected to selection according to 'resistant hepatocyte' protocol, was coupled, 7 weeks after initiation, with liver DNA hypomethylation and with a fall in S-adenosylmethionine/S-adenosylhomocysteine (SAM/SAH) ratio, and in 5-methylthio-adenosine (MTA) content. A 15-day treatment with SAM, started 1 week after selection, caused a dose-dependent decrease in the development of GGT-positive foci, recovery of liver SAM/SAH ratio and MTA level, and liver DNA methylation. A 12-day treatment with 20 mumol/kg per day of 5-azacytidine (AzaC), starting 1 week after selection, enhanced growth of GGT-positive foci, caused strong DNA hypomethylation, and partially counteracted the inhibition of GGT-positive foci growth, without affecting recovery of SAM/SAH ratio and MTA level, induced by SAM. These results suggest a role of DNA methylation in the antipromoting effect of SAM.
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Azacitidina/farmacologia , Biomarcadores Tumorais/análise , Desoxiadenosinas , Neoplasias Hepáticas Experimentais/patologia , Fígado/patologia , Lesões Pré-Cancerosas/patologia , S-Adenosilmetionina/farmacologia , gama-Glutamiltransferase/biossíntese , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Dietilnitrosamina , Fígado/efeitos dos fármacos , Fígado/enzimologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/enzimologia , Masculino , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/enzimologia , Ratos , Ratos Endogâmicos , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo , Tionucleosídeos/metabolismoRESUMO
Large numbers of the snail Terebralia palustris (Linnaeus) (Potamididae; Gastropoda) are frequently observed feeding in a cluster on a single fallen mangrove leaf, yet none are present on leaves nearby. Consequently, we investigated the food-finding ability of T. palustris in a Kenyan mangrove forest using field experiments. We estimated the attractive effect of different cues and analysed the paths (video-recorded) of snails when approaching a food-related odour. This intertidal snail can potentially use both air-borne and water-borne odours to locate food. T. palustris is attracted to conspecifics feeding on leaves, while intact leaves as well as non-feeding snails are not attractive. Moreover, the guiding stimulus appears to be compounds released when the leaves are damaged.T. palustris also seems able to discriminate between different food items; it is more strongly attracted to green mangrove leaves than senescent or fallen ones or mangrove propagules, probably because green leaves release a greater amount of attractive cues.Feeding snails thus recruit more snails to feed on the same leaf. The ecological implications of this behaviour are discussed: a large number of snails on the same leaf counteracts the ability of crabs to remove the leaf being eaten by the snails.
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An experimental investigation of optical fiber transmission of high power excimer laser radiation is presented. Different types of commercially available UV fiber have been tested, measuring energy handling capabilities and transmission losses of short samples at the XeCl (308-nm) and KrF (249-nm) wavelengths by using a standard excimer laser. A power density dependent damage process has been observed over 1 GW/cm(2). Fiber losses due to different radii of curvature are also reported. Experimental results have been examined to evaluate the effectiveness of excimer laser transmission through optical fibers for such medical uses as laser angioplasty, including also a comparison between the use of KrF or XeCl emission lines for this purpose. Finally, optimum excimer laser characteristics to increase the energy coupling in fibers are discussed.
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The diffraction-limited beam of a copper vapor laser employing a self-filtering unstable resonator was used to induce second harmonic generation in a nonlinear crystal of beta-barium borate. Despite the moderate emission characteristics of our small-scale laser device (1.5-W average power, 25-kW peak power at 511 nm), we obtained average and peak power conversion efficiencies of approximately 20 and 30%, respectively, which improved on the previously reported results by a factor of 2.
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We investigated whether Thalamita crenata, a swimming crab found on the East African intertidal flats, uses landmarks to locate its refuges. We modified the visual panorama of an intertidal flat, using conspicuous movable objects, and conducted homing trials with the local population of swimming crabs. In the first set of trials, after being moved away from their dens, the crabs were immediately able to find other known dens, using direct shortcut paths. In the second set of trials we moved all the artificial landmarks surrounding a crab's den 5 m away and then displaced the crab itself. The crabs made initial navigational errors in accordance with the new position of the landmarks; this shows that they oriented themselves by remembering the landmarks. We then repositioned the landmarks and released the crabs far from the familiar area, on a similar flat. This time the crabs could rely only on the artificial landmarks; they used this information and reached the point where home should have been according to the landmarks. Thus, T. crenata showed good spatial knowledge, based on the storage of landmark memories. This orienting mechanism is much more flexible and complex than those of other crabs and is comparable to the route-based memory of honeybees, Apis mellifera. Copyright 2000 The Association for the Study of Animal Behaviour.
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We report the first study of the application of excimer lasers in dentistry for the treatment of dental root canals. High-energy ultraviolet (UV) radiation emitted by an XeCl excimer laser (308 nm) and delivered through suitable optical fibers can be used to remove residual organic tissue from the canals. To this aim, UV ablation thresholds of dental tissues have been measured, showing a preferential etching of infiltrated dentin in respect to healthy dentin, at laser fluences of 0.5-1.5 J/cm2. This technique has been tested on extracted tooth samples, simulating a clinical procedure. Fibers of decreasing core diameters have been used to treat different sections of the root canal down to its apical portion, resulting in an effective, easy, and fast cleaning action. Possible advantages of excimer laser clinical applications in respect to usual procedures are also discussed.
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Terapia a Laser , Tratamento do Canal Radicular/métodos , Tecnologia de Fibra Óptica , Humanos , Técnicas In Vitro , Fibras Ópticas , Raios UltravioletaRESUMO
A diagnostic technique to detect residual tissues at different levels of the root canal during an endodontic treatment is presented. The diagnostic system is based on ultraviolet-induced fluorescence spectroscopy and uses suitable optical fibers for local delivery of excitation light and to collect back fluorescence spectra. Spectra of root canal tissues have been obtained from split teeth by labeling with a fluorescent solution. Residual tissue can be discriminated in respect to healthy dentin because of their different spectral responses: the spectral shape of the first response shows a clear peak at 530 nm because of a selective absorption of the fluorescent dye, whereas for the second response, the spectral curve monotonically increases toward ultraviolet wave-lengths with no particular structure. This technique has been tested on unsplit teeth simulating operative conditions. A compact spectroscopic system has been devised that can be easily integrated in an excimer laser system to perform residual tissue detection during laser cleaning of the canals.
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Lasers , Tratamento do Canal Radicular , Espectrofotometria Ultravioleta , Tecnologia de Fibra Óptica , Humanos , Técnicas In Vitro , Fibras ÓpticasRESUMO
The second-order parametric lens effect shows a temporal limit as a saturable-absorber device for operation in the ultrafast time region. We present and discuss an extended theoretical model dealing with second-order cascaded processes in a nonstationary condition. Experimentally we report the detection of the time-averaged lens effect in the hundred-of-femtoseconds range, discussing the limits that arise in this ultrafast optical region.
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BACKGROUND AND OBJECTIVE: The evolution of pressure waves induced by argon-fluoride laser ablation of the cornea in the typical operative conditions of clinical laser keratectomy has been studied experimentally and analyzed. MATERIALS AND METHODS: Freshly enucleated porcine eyes were irradiated at a laser fluence of 180 mJ/cm2 with various spot diameters in the range 1-6.5 mm. Pressure transients were detected by a fast rise time needle hydrophone inserted into the eyeball from the posterior pole and moved along the eye optical axis toward the cornea. RESULTS: Pressure peaks as high as 90 bar and 50 ns pulse duration (FWHM) were measured in the anterior chamber. Observation of the pulse shape evolution during propagation put in evidence the onset of a marked rarefaction phase following the compressional spike, with intense negative peaks (up to -40 bar) located at increasing distances from the corneal surface for increasing spot diameters. CONCLUSIONS: This behavior was explained by means of simplified models describing pressure pulse generation and diffraction effects occurring during its propagation. Implications to clinical procedures, as possible damages due to tissue stretching and cavitation formation, are also discussed.