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1.
Braz J Otorhinolaryngol ; 90(2): 101360, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38035470

RESUMO

OBJECTIVES: To analyze the clinical utility of a clinical risk scale to predict the need for advanced airway management in patients with deep neck abscess. METHODS: Observational, analytical, cross-sectional study. Patients over 18 years old, both genders, with surgical management of a deep neck abscess, between January 1st, 2015 to December 31th, 2021, who were applied the clinical risk scale (https://7-414-5-19.shinyapps.io/ClinicalRiskScore/). The sensitivity, specificity, and predictive values of the scale were calculated based on the identified clinical outcomes. A p<0.05 was considered significant. RESULTS: A sample of 213 patients was obtained, 121 (56.8%) men, of whom 50 (23.5%) required advanced airway management. Dyspnea was the variable with the most statistical weight in our study, (p=0.001) as well as the multiple spaces involvement, (p=0.001) the presence of air corpuscles, (p=0.001) compromise of the retropharyngeal space (p=0.001) and age greater than 55 years (p=0.001). Taking these data into account, were found for the clinical risk scale a sensitivity of 97% and a specificity of 65% (p=0.001, 95% CI 0.856-0.984). CONCLUSIONS: The clinical risk scale developed to predict advanced airway management in patients with a diagnosis of deep neck abscess may be applicable in our environment with high sensitivity and specificity. LEVEL OF EVIDENCE: IV.


Assuntos
Abscesso Retrofaríngeo , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Adolescente , Estudos Transversais , Estudos Retrospectivos , Pescoço , Manuseio das Vias Aéreas
2.
Polymers (Basel) ; 15(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37836059

RESUMO

Thermoplastic polyurethanes (TPUs) are remarkably versatile polymers due to the wide range of raw materials available for their synthesis, resulting in physicochemical characteristics that can be tailored according to the specific requirements of their final applications. In this study, a renewable bio-based polyol obtained from soybean oil is used for the synthesis of TPU via reactive extrusion, and the influence of the bio-based polyol on the multi-phase structure and properties of the TPU is studied. As raw materials, 4,4'-diphenylmethane (MDI), 1,4-butanediol, a fossil-based polyester polyol, and a bio-based polyol are used. The fossil-based to soybean-based polyol ratios studied are 100/0, 99/1, 95/5, 90/10, 80/20, and 50/50% by weight, respectively. The TPUs were characterized by size exclusion chromatography (SEC), gel content analysis, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), dynamic mechanical analysis (DMA), and contact angle measurements. The results reveal that incorporating the renewable polyol enhances the compatibility between the rigid and flexible segments of the TPU. However, due to its high functionality, the addition of soybean-based polyol can promote cross-linking. This phenomenon reduces the density of hydrogen bonds within the material, also reducing polarity and restricting macromolecular mobility, as corroborated by higher glass transition temperature (Tg) values. Remarkably, the addition of small amounts of the bio-based polyol (up to 5 wt.% of the total polyol content) results in high-molecular-weight TPUs with lower polarity, combined with suitable processability and mechanical properties, thus broadening the range of applications and improving their sustainability.

3.
Polymers (Basel) ; 15(10)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37242875

RESUMO

Hybrid materials have been studied because in these materials the properties of organic components, such as elasticity and biodegradability, could be combined with the properties of inorganic components, such as good biological response, thereby transforming them into a single material with improved properties. In this work, Class I hybrid materials based on polyester-urea-urethanes and titania were obtained using the modified sol-gel method. This was corroborated using the FT-IR and Raman techniques which highlighted the formation of hydrogen bonds and the presence of Ti-OH groups in the hybrid materials. In addition, the mechanical and thermal properties and degradability were measured using techniques, such as Vickers hardness, TGA, DSC, and hydrolytic degradation; these properties could be tailored according to hybridization between both organic and inorganic components. The results show that Vickers hardness increased by 20% in hybrid materials as compared to polymers; also, the surface hydrophilicity increases in the hybrid materials, improving their cell viability. Furthermore, cytotoxicity in vitro test was carried out using osteoblast cells for intended biomedical applications and they showed non-cytotoxic behavior.

4.
Foods ; 12(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36832820

RESUMO

The Canary Islands, located in the Atlantic Ocean, are an archipelago of volcanic origin which, for decades, has been affected by natural fluoride contamination in the water supply of some of its islands, mainly the island of Tenerife. In addition, recent volcanic eruptions in the archipelago and the increased demand for water supply have led to an increase in the fluoride content in other areas which, historically, were not affected. Fluoride content was determined in 274 water supply samples from the most populated islands of the Canary Islands (Tenerife and Gran Canaria) collected during the months of June 2021 to May 2022. The samples were analysed by fluoride ion selective potentiometry. The highest concentrations in Tenerife were found in the municipalities of Sauzal (7.00 mg/L) and Tegueste (5.39 mg/L), both water samples are over the parametric value of 1.5 mg/L set in the supply water legislation. In the Gran Canaria Island, the highest fluoride levels were found in Valsequillo and Mogán with 1.44 mg/L in both locations, but under the parametric fluoride value abovementioned. Consumption of just 1 L of water per day in the El Sauzal area would result in a contribution rate of 77% for adults and children over 15 years of age (Upper Level value of 7 mg/day) and 108% for children 9-14 years of age (UL value of 5 mg/day). The contribution rates increase considerably, reaching or exceeding 100% of the reference value (UL) with increasing consumption of 1 to 2 L of water per day. Therefore, it is considered that there is a health risk of overexposure to fluoride on the island of Tenerife. In the case of the island of Gran Canaria, it has been shown that even the consumption of 2 litres of water per day does not confer contribution rates that pose a health risk.

5.
Polymers (Basel) ; 14(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35956679

RESUMO

Thermoplastic polyurethanes (TPUs) are versatile polymers presenting a broad range of properties as a result of their countless combination of raw materials­in essence, isocyanates, polyols, and chain extenders. This study highlights the effect of two different chain extenders and their combination on the structure−property relationships of TPUs synthesized by reactive extrusion. The TPUs were obtained from 4,4-diphenylmethane diisocyanate (MDI), polyester diols, and the chain extenders 1,4-butanediol (BDO) and dipropylene glycol (DPG). The BDO/DPG ratios studied were 100/0, 75/25, 50/50, 25/75, and 0/100 wt.%. The TPUs were characterized by size exclusion chromatography (SEC), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), UV−vis spectroscopy, and physical-mechanical properties. The results indicate that DPG promotes compatibility between rigid (HS) and flexible (SS) segments of TPUs. Consequently, increasing DPG content (>75 wt.%) reduced the organization of the rigid segments and the degree of phase separation, increasing the polydispersity of the interdomain distance and the transparency in the UV−visible spectrum of the TPUs. Furthermore, increasing DPG content also reduced the amount of hydrogen bonds present in the rigid phase, reducing or extinguishing its glass transition temperature (TgHS) and melting temperature (Tm), and increasing the glass transition temperature of the flexible phase (TgSS). Therefore, increasing DPG content leads to a deterioration in mechanical properties and hydrolysis resistance.

6.
Front Vet Sci ; 8: 604560, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33778034

RESUMO

Many human emergent and re-emergent diseases have a sylvatic cycle. Yet, little effort has been put into discovering and modeling the wild mammal reservoirs of dengue (DENV), particularly in the Americas. Here, we show a species-level susceptibility prediction to dengue of wild mammals in the Americas as a function of the three most important biodiversity dimensions (ecological, geographical, and phylogenetic spaces), using machine learning protocols. Model predictions showed that different species of bats would be highly susceptible to DENV infections, where susceptibility mostly depended on phylogenetic relationships among hosts and their environmental requirement. Mammal species predicted as highly susceptible coincide with sets of species that have been reported infected in field studies, but it also suggests other species that have not been previously considered or that have been captured in low numbers. Also, the environment (i.e., the distance between the species' optima in bioclimatic dimensions) in combination with geographic and phylogenetic distance is highly relevant in predicting susceptibility to DENV in wild mammals. Our results agree with previous modeling efforts indicating that temperature is an important factor determining DENV transmission, and provide novel insights regarding other relevant factors and the importance of considering wild reservoirs. This modeling framework will aid in the identification of potential DENV reservoirs for future surveillance efforts.

7.
Cent European J Urol ; 73(3): 307-314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133658

RESUMO

INTRODUCTION: In 2004, Patricia Skilling developed a new squatting-based pelvic floor rehabilitation method based on strengthening the three reflex pelvic muscles and ligaments hypothesized to control the closure and micturition reflexes. We adapted these methods to test our hypothesis that day/night enuresis was due to the inability of these muscles/ligaments to control an inappropriately activated micturition reflex. MATERIAL AND METHODS: The trial commenced as a randomized control trial to be conducted over 4 months, but was converted to a prospective trial at 4 weeks by order of the Ethics Committee. A total of 48 children, 7.6 ±2.5 years, 34 females, 14 males, had strictly supervised exercises twice daily, 10 squats, 10 bridge, fitball exercises involving proprioception exercises with surface perineal electromyogram (EMG) once a week.Eligibility criteria were daytime urine leakage plus night-time bedwetting. Exclusion criterion was refusal to sign consent forms. Assessment was done by intention to treat. The criterion for cure was complete dryness. RESULTS: At 1st review (4 weeks) 12/24 in the treatment group reported total cure of wetting; 41/48 children (86%) were cured of both daytime/nighttime enuresis (p <0.001) at 4 months. There were no adverse events. Secondary outcomes were concomitant cure of constipation, fecal incontinence, urinary retention as predicted by the underlying integral theory of incontinence. CONCLUSIONS: We believe our methods accelerated normal childhood strengthening of muscles/ligaments which control inappropriate activation of the micturition reflex which we hypothesize is the basis for daytime/nighttime enuresis. This is a simple treatment, needs diligent application and validation by others.

8.
Polymers (Basel) ; 12(11)2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33213051

RESUMO

In the present work, the synthesis of segmented polyurethanes functionalized with catechol moieties within the hard or the soft segment is presented. For this purpose, a synthetic route of a new catechol diol was designed. The direct insertion of this catechol-free derivative into the rigid phase led to segmented polyurethanes with low performance (σmax ≈ 4.5 MPa). Nevertheless, when the derivative was formally located within the soft segment, the mechanical properties of the corresponding functionalized polyurethane improved considerably (σmax ≈ 16.3 MPa), owing to a significant increase in the degree of polymerization. It is proposed that this difference in reactivity could probably be attributed to a hampering effect of this catecholic ring during the polyaddition reaction. To corroborate this hypothesis, a protection of the aromatic ring was carried out, blocking the hampering effect and avoiding secondary reactions. The polyurethane bearing the protected catechol showed the highest molecular weight and the highest stress at break described to date (σmax ≈ 66.1 MPa) for these kind of catechol-functionalized polyurethanes. Therefore, this new approach allows for the obtention of high-performance polyurethane films and can be applied in different sectors, benefiting from the molecular adhesion introduced by the catechol ring.

10.
Syst Biol ; 67(6): 1041-1060, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30339252

RESUMO

The subtribe Espeletiinae (Asteraceae), endemic to the high-elevations in the Northern Andes, exhibits an exceptional diversity of species, growth-forms, and reproductive strategies. This complex of 140 species includes large trees, dichotomous trees, shrubs and the extraordinary giant caulescent rosettes, considered as a classic example of adaptation in tropical high-elevation ecosystems. The subtribe has also long been recognized as a prominent case of adaptive radiation, but the understanding of its evolution has been hampered by a lack of phylogenetic resolution. Herein, we produce the first fully resolved phylogeny of all morphological groups of Espeletiinae, using whole plastomes and about a million nuclear nucleotides obtained with an original de novo assembly procedure without reference genome, and analyzed with traditional and coalescent-based approaches that consider the possible impact of incomplete lineage sorting and hybridization on phylogenetic inference. We show that the diversification of Espeletiinae started from a rosette ancestor about 2.3 Ma, after the final uplift of the Northern Andes. This was followed by two independent radiations in the Colombian and Venezuelan Andes, with a few trans-cordilleran dispersal events among low-elevation tree lineages but none among high-elevation rosettes. We demonstrate complex scenarios of morphological change in Espeletiinae, usually implying the convergent evolution of growth-forms with frequent loss/gains of various traits. For instance, caulescent rosettes evolved independently in both countries, likely as convergent adaptations to life in tropical high-elevation habitats. Tree growth-forms evolved independently three times from the repeated colonization of lower elevations by high-elevation rosette ancestors. The rate of morphological diversification increased during the early phase of the radiation, after which it decreased steadily towards the present. On the other hand, the rate of species diversification in the best-sampled Venezuelan radiation was on average very high (3.1 spp/My), with significant rate variation among growth-forms (much higher in polycarpic caulescent rosettes). Our results point out a scenario where both adaptive morphological evolution and geographical isolation due to Pleistocene climatic oscillations triggered an exceptionally rapid radiation for a continental plant group.


Assuntos
Asteraceae/classificação , Asteraceae/genética , Genoma de Planta/genética , Filogenia , Adaptação Fisiológica/genética , Colômbia , Clima Tropical , Venezuela
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