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1.
Acta Chir Plast ; 66(1): 31-33, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38704236

RESUMO

Indwelling intravascular catheters are important tools in the care of critically ill patients; however, they have an inherent risk of infection or thromboembolic events. Reports on catheter associated thromboembolic events in burn units are rare, despite being well recognized that burn patients bear an increased baseline risk for thromboembolic events. We describe two catheter-associated thromboembolic complications in burn patients in a burn unit and the morbidity associated with these events. Patients with endovascular catheters in burn units may be at increased risk for severe thromboembolic events associated with intravascular catheters, but specific guidelines for prevention and management of these patients are still missing.


Assuntos
Unidades de Queimados , Queimaduras , Tromboembolia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Queimaduras/complicações , Cateteres de Demora/efeitos adversos , Tromboembolia/etiologia , Tromboembolia/prevenção & controle
2.
BMC Med Educ ; 23(1): 761, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828485

RESUMO

BACKGROUND: Life expectancy in recent decades has increased the prevalence of chronic diseases in the population, requiring an approach to new health topics, such as discussions on quality of life and expectations about death and dying. The concept of advance directives (ADs) gives individuals the opportunity to make known their decisions about the treatments they would like to receive at the end of life. Despite the recognition of relevance in clinical practice, the applicability of the concept presents challenges, including establishing the appropriate prognosis for each patient and the ideal time to approach the patient. Some prognostic tools were developed, such as the surprise question (SQ): "Would you be surprised if your patient died in 12 months?", which is used in some clinical settings to predict patient deaths and to make decisions regarding ADs. The main objective of the present study was to evaluate the behavior of second-year resident physicians (PGY-2) when the SQ was applied. METHOD: In our observational study, from July 1, 2016, to February 28, 2017, (PGY-2) in the Internal Medicine Residency Program (IMRP) applied SQ to all patients with multiple and varied chronic no communicable comorbidities, who were followed up at the general medicine outpatient clinic (GMOC) of a tertiary university hospital in São Paulo- Brazil. The frequency of the outcome (death or non-death within 12 months) was analyzed by correlating it with the clinical data (impact of the studied variables). RESULTS: Eight hundred forty patients entered the study. Fitfty-two of them (6.2%) died within one year. PGY-2 predicted that two hundred and fourteen patients (25.5% of total) would die within a year (answer No to SQ), of which, 32 (14.9%) did so. The correct residents' prognosis for the subgroup of 626 patients (answer "Yes" to SQ) was NPV = 96.8% (CI = 95.4%-98.2%) and PPV = 14.9% (CI 10.1%-19, 6%). Answering "Yes" to SQ correlated negatively to addressing AD while the outcomes death and the answer No to SQ were positively correlated, according to the number of comorbidities. CONCLUSION: The SQ, in addition to care, contributed to health education, communication and care planning shared by the doctor and patient.


Assuntos
Pacientes Ambulatoriais , Cuidados Paliativos , Humanos , Prognóstico , Qualidade de Vida , Estudos Prospectivos , Brasil/epidemiologia
3.
Environ Geochem Health ; 45(4): 1165-1171, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35044549

RESUMO

When the SEGH international board released a short editorial paper back in 2019, we described an aim to increase the membership offering, whilst improving the diversity of input regionally, by scientific discipline and to ensure greater and more regular contact across the regions from 2020 onwards. Wider aspirations described in 2019 (Watts et al. 2019) are discussed within this short communication at the end of 2021 to evaluate progress made. In particular, how the SEGH community adapted to the unprecedented circumstances that have challenged each and every one of us throughout the COVID-19 pandemic since early 2020 and are likely to influence our activities for the foreseeable future.


Assuntos
Saúde Ambiental , Ciência Ambiental , Sociedades , Humanos , COVID-19/epidemiologia , Pandemias
4.
Phytopathology ; 109(6): 916-931, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30852973

RESUMO

Vitis vinifera is affected by many diseases every year, depending on causal agents, susceptibility of cultivars, and climate region. Some are caused by a single agent, such as gray mold caused by Botrytis cinerea or powdery mildew caused by Erysiphe necator. Others result from the actions of a complex of pathogens such as grapevine trunk diseases (GTDs). GTDs are presently among the most devastating diseases in viticulture worldwide because both the economic losses and the long-term sustainability of vineyards are strongly affected. The complexity of GTDs results from the diversity of associated fungi, the undetermined period of latency within the vine (asymptomatic status), the erratic foliar symptom expression from one year to the next, and, probably correlated with all of these points, the lack of efficient strategies to control them. Distinct methods can be beneficial to improve our knowledge of GTDs. In vitro bioassays with cell suspensions, calli, foliar discs, full leaves, or plantlets, and in vivo natural bioassays with cuttings, grafted plants in the greenhouse, or artificially infected ones in the vineyard, can be applied by using progressive integrative levels of in vitro and in vivo, depending on the information searched. In this review, the methods available to understand GTDs are described in terms of experimental procedures, main obtained results, and deliverable prospects. The advantages and disadvantages of each model are also discussed.


Assuntos
Ascomicetos , Vitis , Doenças das Plantas , Folhas de Planta , Vitis/microbiologia
5.
Nano Lett ; 18(3): 1660-1667, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29451801

RESUMO

We develop and perform continuum mechanics simulations of carbon nanotube (CNT) deployment directed by a combination of surface topography and rarefied gas flow. We employ the discrete elastic rods method to model the deposition of CNT as a slender elastic rod that evolves in time under two external forces, namely, van der Waals (vdW) and aerodynamic drag. Our results confirm that this self-assembly process is analogous to a previously studied macroscopic system, the "elastic sewing machine", where an elastic rod deployed onto a moving substrate forms nonlinear patterns. In the case of CNTs, the complex patterns observed on the substrate, such as coils and serpentines, result from an intricate interplay between van der Waals attraction, rarefied aerodynamics, and elastic bending. We systematically sweep through the multidimensional parameter space to quantify the pattern morphology as a function of the relevant material, flow, and geometric parameters. Our findings are in good agreement with available experimental data. Scaling analysis involving the relevant forces helps rationalize our observations.

6.
Phys Chem Chem Phys ; 20(29): 19307-19313, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-29900442

RESUMO

In this work, we have found complete water miscibility for a priori, water immiscible (highly hydrophobic) ionic liquids by chemical manipulation of the quaternary ammonium cation grafted with hydroxyethyl moieties. Specifically, we were able to obtain bistriflimide-based ionic liquids completely miscible with water, even below room temperature. The underlying reason is the full integration of the OH groups of the cation in the continuous H-bonded network of water.

7.
Phys Rev Lett ; 115(11): 118302, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26406861

RESUMO

We combine experiments and theory to study the mechanics of overhand knots in slender elastic rods under tension. The equilibrium shape of the knot is governed by an interplay between topology, friction, and bending. We use precision model experiments to quantify the dependence of the mechanical response of the knot as a function of the geometry of the self-contacting region, and for different topologies as measured by their crossing number. An analytical model based on the nonlinear theory of thin elastic rods is then developed to describe how the physical and topological parameters of the knot set the tensile force required for equilibrium. Excellent agreement is found between theory and experiments for overhand knots over a wide range of crossing numbers.

8.
Phys Rev Lett ; 115(16): 168101, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26550904

RESUMO

We combine experiments with simulations to investigate the fluid-structure interaction of a flexible helical rod rotating in a viscous fluid, under low Reynolds number conditions. Our analysis takes into account the coupling between the geometrically nonlinear behavior of the elastic rod with a nonlocal hydrodynamic model for the fluid loading. We quantify the resulting propulsive force, as well as the buckling instability of the originally helical filament that occurs above a critical rotation velocity. A scaling analysis is performed to rationalize the onset of this instability. A universal phase diagram is constructed to map out the region of successful propulsion and the corresponding boundary of stability is established. Comparing our results with data for flagellated bacteria suggests that this instability may be exploited in nature for physiological purposes.


Assuntos
Fenômenos Fisiológicos Bacterianos , Modelos Biológicos , Locomoção , Natação , Viscosidade
9.
Genet Mol Res ; 14(2): 6323-9, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26125836

RESUMO

The present study aimed to assess the cytotoxic, genotoxic, and antigenotoxic activities of sucupira oil (Pterodon emarginatus), which is commonly used as an anti-rheumatic, analgesic, antimicrobial, anticercariae, and anti-inflammatory. We used the mouse bone marrow micronucleus test as an experimental model. The experimental groups, which consisted of 5 animals, was administered sucupira oil (100 mg/kg body weight) intraperitoneally and evaluated 24 h after the treatment. The negative control group was treated with sterile distilled water, and the positive control group received an intraperitoneal dose of 4 mg/kg mitomycin C, a dose that corresponds to 80% of its median lethal dose. Cytotoxicity was determined by the polychromatic to normochromatic erythrocytes ratio (PCE/NCE). Sucupira oil had no significant effects (P > 0.05) on the frequency of micronucleated polychromatic erythrocytes as compared to the negative control group. However, the difference was significant (P < 0.005) as compared to the positive control group. The PCE/NCE (100 mg/kg oil and 4 mg/kg mitomycin) ratio did not differ between the experimental group and the positive control group, but it differed significantly when compared to the negative control group (P < 0.05). Thus, these findings suggested that the P. emarginatus oil showed no cytotoxic, mutagenic, or antimutagenic activities at a dose of 100 mg/kg.


Assuntos
Antimutagênicos/administração & dosagem , Células da Medula Óssea/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Óleos de Plantas/administração & dosagem , Animais , Antimutagênicos/química , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Fabaceae/química , Camundongos , Testes para Micronúcleos , Mutagênicos/toxicidade , Óleos de Plantas/química
10.
Phys Rev Lett ; 112(6): 068103, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24580710

RESUMO

We investigate how natural curvature affects the configuration of a thin elastic rod suspended under its own weight, as when a single strand of hair hangs under gravity. We combine precision desktop experiments, numerics, and theoretical analysis to explore the equilibrium shapes set by the coupled effects of elasticity, natural curvature, nonlinear geometry, and gravity. A phase diagram is constructed in terms of the control parameters of the system, namely the dimensionless curvature and weight, where we identify three distinct regions: planar curls, localized helices, and global helices. We analyze the stability of planar configurations, and describe the localization of helical patterns for long rods, near their free end. The observed shapes and their associated phase boundaries are then rationalized based on the underlying physical ingredients.

11.
Arch Soc Esp Oftalmol (Engl Ed) ; 99(8): 347-351, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38710368

RESUMO

A 40-year-old man who attended the emergency department with a scotoma in right eye. He mentioned hearing difficulties and headache for months and he had sensory and motor deficits in the previous days. In the ophthalmic examination, the right eye had areas of arterial occlusion. MRI revealed hyperintense lesions. The patient was diagnosed with Susac syndrome. He was treated with systemic steroids, however, it was not enough to control the condition. Rituximab and intravenous immunoglobulins were added, which allowed the improvement of neurological symptoms, but the alteration of the visual field and the hearing defect did not recover. Early diagnosis of this pathology is essential, since delaying treatment can cause irreversible consequences. Sometimes it is difficult given the wide variety of symptoms and the course of the disease. Ocular manifestations may raise suspicion when the general symptoms are nonspecific.


Assuntos
Síndrome de Susac , Humanos , Síndrome de Susac/diagnóstico , Síndrome de Susac/tratamento farmacológico , Masculino , Adulto , Imunoglobulinas Intravenosas/uso terapêutico , Imageamento por Ressonância Magnética , Rituximab/uso terapêutico , Escotoma/etiologia , Escotoma/diagnóstico
12.
Gene ; 852: 147047, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36379381

RESUMO

Lung cancer patients with COVID-19 present an increased risk of developing severe disease and, consequently, have poor outcomes. Determining SARS-CoV-2-host interactome in lung cancer cells and tissues, infected or uninfected with SARS-CoV-2, may reveal molecular mechanisms associated with COVID-19 development and severity in lung cancer patients. Here, we integrated transcriptome data of lung tumors from patients with small- or non-small cell lung cancer (SCLC and NSCLC) and normal lung and lung cancer cells infected with SARS-CoV-2. We aimed to characterize molecular mechanisms potentially associated with COVID-19 development and severity in lung cancer patients and to predict the SARS-CoV-2-host cell interactome. We found that the gene expression profiles of lung cell lines infected with SARS-CoV-2 resemble more primary lung tumors than non-malignant lung tissues. In addition, the transcriptomic-based interactome analysis of SCLC and NSCLC revealed increased expression of cancer genes BRCA1 and CENPF, whose proteins are known or predicted to interact with the SARS-CoV-2 spike glycoprotein and helicase, respectively. We also found that TRIB3, a gene coding a putative host-SARS-CoV-2 interacting protein associated with COVID-19 infection, is co-expressed with the up-regulated genes MTHFD2, ADM2, and GPT2 in all tested conditions. Our analysis identified biological processes such as amino acid metabolism and angiogenesis and 22 host mediators of SARS-CoV-2 infection and replication that may contribute to the development and severity of COVID-19 in lung cancers.


Assuntos
COVID-19 , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Transcriptoma , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , COVID-19/genética , COVID-19/patologia , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , SARS-CoV-2
13.
Phys Rev Lett ; 109(14): 144301, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-23083245

RESUMO

We present results from an experimental investigation of the indentation of nonspherical pressurized elastic shells with a positive Gauss curvature. A predictive framework is proposed that rationalizes the dependence of the local rigidity of an indented shell on the curvature in the neighborhood of the locus of indentation, the in-out pressure differential, and the material properties. In our approach, we combine classic theory for spherical shells with recent analytical developments for the pressurized case, and proceed, for the most part, by analogy, guided by our own experiments. By way of example, our results elucidate why an eggshell is significantly stiffer when compressed along its major axis, as compared to doing so along its minor axis. The prominence of geometry in this class of problems points to the relevance and applicability of our findings over a wide range of length scales.


Assuntos
Casca de Ovo/química , Modelos Teóricos , Animais , Fenômenos Biomecânicos , Galinhas , Elasticidade , Modelos Lineares , Pressão
14.
Pharmazie ; 67(4): 355-60, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22570943

RESUMO

The present work evaluates wound healing activity of leaves extracts of Symphytum officinale L. (comfrey) incorporated in three pharmaceutical formulations. Wound healing activity of comfrey was determined by qualitative and quantitative histological analysis of open wound in rat model, using allantoin as positive control. Three topical formulations, carbomer gel, glycero-alcoholic solution and O/W emulsion (soft lotion) were compared. The histological analysis of the healing process shows significant differences in treatment, particularly on its intensity and rate. The results indicate that emulsion containing both extracts, commercial and prepared, induced the largest and furthest repair of damaged tissue. This could be evidenced from day 3 to 28 by increase in collagen deposition from 40% to 240% and reduction on cellular inflammatory infiltrate from 3% to 46%. However, 8% prepared extract in emulsion presented the best efficacy. This work clearly demonstrates that comfrey leaves have a wound healing activity. The O/W emulsion showed to be the vehicle most effective to induce healing activity, particularly with extracts obtained from comfrey leaves collected in Minas Gerais state in Brazil. It shows the best efficacy to control the inflammatory process and to induce collagen deposition at 8% concentration.


Assuntos
Confrei/química , Cicatrização/efeitos dos fármacos , Administração Tópica , Alantoína/farmacologia , Animais , Química Farmacêutica , Emulsões , Feminino , Inflamação/patologia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos , Ratos Wistar , Pele/lesões , Pele/patologia , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/patologia
15.
Phys Rev Lett ; 106(20): 204302, 2011 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-21668232

RESUMO

We present results of a hybrid experimental and theoretical investigation of the fracture scaling in scratch tests and show that scratching is a fracture dominated process. Validated for paraffin wax, cement paste, Jurassic limestone and steel, we derive a model that provides a quantitative means to relate quantities measured in scratch tests to fracture properties of materials at multiple scales. The scalability of scratching for different probes and depths opens new venues towards miniaturization of our technique, to extract fracture properties of materials at even smaller length scales.

16.
J Dairy Sci ; 94(3): 1223-38, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21338788

RESUMO

Despite its relevance to sensory features and to fundamental explanation of the changes observed throughout cheese ripening, microstructural studies of specialty cheeses have lagged far behind those of industrialized cheeses. Hence, the purpose of this study was to pinpoint microstructural differences in the gel network of traditional Serra da Estrela cheese throughout ripening, using 2-dimensional image analysis, and to unfold correlations of such microstructural indicators with classical bulk chemical and textural parameters. Hence, samples were taken throughout the ripening period, following a nested design; uniform thin sections were systematically observed via light microscopy (LM, 200 ×) and transmission electron microscopy (TEM, 4,400 ×), and computer-assisted quantitative analysis of digital images was comprehensively performed following standard stereological methodology. Fresh cheeses exhibited the highest porosity and ratio of surface area to volume. Significant negative correlations were found between microstructural parameters and proteolysis indicators. Light microscopy images suggested that rearrangements exist, up to 21 d, of the cheese matrix that leave porosity and pores unchanged, whereas TEM images indicated a significant decrease in number of pores within the same time frame, especially those above 1 × 10(-2) µm(2) in area. The larger pores, chiefly with cross-sectional areas above 40 µm(2), were less represented by the end of ripening-and likely explain the observed significant decrease of cheese porosity without a change in number of pores. Field viewing significantly affected the microstructural parameter values, whereas section viewing affected significantly only LM-based ones. Categorical principal component analysis between the 2 types of microstructural data sets was performed, and permitted discrimination of each stage of ripening. Multiple linear regression analysis indicated that the variables associated with the nitrogen fraction were well predicted by stereological-based parameters (R(2) ≥ 0.96). Therefore, our findings demonstrate the potential of image analysis to monitor microstructure throughout ripening, and that the microstructure revealed by LM reflects more clearly cheese aging than that revealed by TEM.


Assuntos
Queijo/análise , Manipulação de Alimentos , Tecnologia de Alimentos/métodos , Animais , Processamento de Imagem Assistida por Computador/métodos , Microscopia/métodos , Microscopia/veterinária , Microscopia Eletrônica de Transmissão/métodos , Microscopia Eletrônica de Transmissão/veterinária
17.
Braz J Biol ; 82: e234476, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681898

RESUMO

The Brazilian Cerrado biome consists of a great variety of endemic species with several bioactive compounds, and Anadenanthera peregrina (L.) Speg is a promising species. In this study, we aimed to perform phytochemical characterization and evaluate the antioxidant and antibacterial activities against Staphylococcus aureus and Escherichia coli of the hydroethanolic extract of A. peregrina stem bark. The barks were collected in the Botanical Garden of Goiânia, Brazil. The hydroethanolic extract was obtained by percolation and subjected to physicochemical screening, total phenolic content estimation, high-performance liquid chromatography (HPLC) fingerprinting, and antioxidant (IC50 values were calculated for the 2,2-diphenyl-1-picrylhydrazyl assay - DPPH) and antibacterial activity determination. The pH of the extract was 5.21 and density was 0.956 g/cm3. The phytochemical screening indicated the presence of cardiac glycosides, organic acids, reducing sugars, hemolytic saponins, phenols, coumarins, condensed tannins, flavonoids, catechins, depsides, and depsidones derived from benzoquinones. The extract showed intense hemolytic activity. The total phenolic content was 6.40 g GAE 100 g-1. The HPLC fingerprinting analysis revealed the presence of gallic acid, catechin, and epicatechin. We confirmed the antioxidant activity of the extract. Furthermore, the extract did not inhibit the growth of E. coli colonies at any volume tested, but there were halos around S. aureus colonies at all three volumes tested. These results contribute to a better understanding of the chemical composition of A. peregrina stem bark and further support the medicinal applications of this species.


Assuntos
Antioxidantes , Casca de Planta , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Brasil , Escherichia coli , Compostos Fitoquímicos , Extratos Vegetais/farmacologia , Staphylococcus aureus
18.
Phys Rev Lett ; 105(19): 194301, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-21231171

RESUMO

We present a hybrid experimental and theoretical study on the oscillatory behavior exhibited by multiple thin sheets under aerodynamic loading. Our clapping book consists of a stack of paper, clamped at the downstream end and placed in a wind tunnel with steady flow. As pages lift off, they accumulate onto a bent stack held up by the wind. The book collapses shut once the elasticity and weight of the pages overcome the aerodynamic force; this process repeats periodically. We develop a theoretical model that predictively describes this periodic clapping process.

19.
Phys Rev Lett ; 105(4): 044301, 2010 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-20867845

RESUMO

We present the results of a combined experimental and theoretical investigation of rolling elastic ribbons. Particular attention is given to characterizing the steady shapes that arise in static and dynamic rolling configurations. In both cases, above a critical value of the forcing (either gravitational or centrifugal), the ribbon assumes a two-lobed, peanut shape similar to that assumed by rolling droplets. Our theoretical model allows us to rationalize the observed shapes through consideration of the ribbon's bending and stretching in response to the applied forcing.

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