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BACKGROUND: The purpose of this study is to report the clinical features and outcomes of Black/African American (AA) and Latino Hispanic patients with Coronavirus disease 2019 (COVID-19) hospitalized in an inter-city hospital in the state of New Jersey. METHODS: This is a retrospective cohort study of AA and Latino Hispanic patients with COVID-19 admitted to a 665-bed quaternary care, teaching hospital located in Newark, New Jersey. The study included patients who had completed hospitalization between March 10, 2020, and April 10, 2020. We reviewed demographics, socioeconomic variables and incidence of in-hospital mortality and morbidity. Logistic regression was used to identify predictor of in-hospital death. RESULTS: Out of 416 patients, 251 (60%) had completed hospitalization as of April 10, 2020. The incidence of In-hospital mortality was 38.6% (n = 97). Most common symptoms at initial presentation were dyspnea 39% (n = 162) followed by cough 38%(n = 156) and fever 34% (n = 143). Patients were in the highest quartile for population's density, number of housing units and disproportionately fell into the lowest median income quartile for the state of New Jersey. The incidence of septic shock, acute kidney injury (AKI) requiring hemodialysis and admission to an intensive care unit (ICU) was 24% (n = 59), 21% (n = 52), 33% (n = 82) respectively. Independent predictors of in-hospital mortality were older age, lower serum Hemoglobin < 10 mg/dl, elevated serum Ferritin and Creatinine phosphokinase levels > 1200 U/L and > 1000 U/L. CONCLUSIONS: Findings from an inter-city hospital's experience with COVID-19 among underserved minority populations showed that, more than one of every three patients were at risk for in-hospital death or morbidity. Older age and elevated inflammatory markers at presentation were associated with in-hospital death.
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Negro ou Afro-Americano/estatística & dados numéricos , Infecções por Coronavirus/etnologia , Infecções por Coronavirus/terapia , Hispânico ou Latino/estatística & dados numéricos , Grupos Minoritários/estatística & dados numéricos , Pneumonia Viral/etnologia , Pneumonia Viral/terapia , Idoso , COVID-19 , Feminino , Mortalidade Hospitalar/etnologia , Hospitalização/estatística & dados numéricos , Hospitais Urbanos , Humanos , Incidência , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , New Jersey/epidemiologia , Pandemias , Estudos Retrospectivos , Medição de Risco , Resultado do TratamentoRESUMO
Biofilm related bacterial infection is one of the primary causes of implant failure. Limiting bacterial adhesion and colonization of pathogenic bacteria is a challenging task in health care. Here, a highly simplistic processing technique for imparting antibacterial properties on a biomedical grade stainless steel is demonstrated. Low-temperature high strain-rate deformation achieved using submerged friction stir processing resulted in a nearly single phase ultra-fine grain structure. The processed stainless steel demonstrated improved antibacterial properties for both Gram-positive and Gram-negative bacteria, significantly impeding biofilm formation during the in vitro study. Also, the processed stainless steel showed better compatibility with human fibroblasts manifested through apparent cell spreading and proliferation. The substantial antibacterial properties of the processed steel are explained in terms of the favorable electronic characteristics of the metal-oxide and by using classical Derjaguin-Landau-Verwey-Overbeek (DLVO) and the extended DLVO (XDLVO) approach at the cell-substrate interface.
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Biofilmes/crescimento & desenvolvimento , Fricção , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Aço Inoxidável/química , Aderência Bacteriana/fisiologia , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Humanos , Propriedades de SuperfícieRESUMO
BACKGROUND: Lung transplant remains an established treatment for end-stage lung disease, but limited organ availability remains a major barrier and contributor to waitlist mortality.1 Only 20% of available organs are considered suitable for lung transplantation (Am J Transplant, 16, 2016 and 141; Thorac Surg Clin, 25, 2015 and 35). Successful lung transplantation has been reported from donors infected with bacterial or fungal organisms, but there is a paucity of evidence regarding the use of donors with bacterial meningitis (Transplant Proc, 32, 2000 and 75; Transplantation, 64, 1997 and 365; Ann Thorac Surg, 86, 2008 and 1554). METHOD: The Cleveland Clinic lung transplant database was retrospectively reviewed for patients between January 1998 and December 2014. Post-transplantation outcomes collected included graft dysfunction, infectious complications, and survival. RESULTS: The recipients were identified as having lungs from donors with bacterial meningitis. All recipients remained free of infectious organisms responsible for bacterial meningitis related in the donor. Severe primary graft dysfunction (PGD) was not seen in these recipients. CONCLUSION: In our study, lung transplantation from increased risk donors with bacterial meningitis was not associated with an increased risk of early infectious complications in recipients. Donors with bacterial meningitis should be considered for lung donation and may expand the donor pool safely.
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Seleção do Doador , Transplante de Pulmão/mortalidade , Meningites Bacterianas/epidemiologia , Alocação de Recursos , Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adulto , Idoso , Causas de Morte , Feminino , Seguimentos , Humanos , Transplante de Pulmão/estatística & dados numéricos , Masculino , Meningites Bacterianas/microbiologia , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto JovemRESUMO
This work investigates the effect of ultrafine-grain microstructure on the oxidation behavior of AlCoCrFeNi high entropy alloy (HEA). The ultrafine-grain microstructure is obtained using stationary friction processing performed at two different rotational speeds, 400 and 1800 rpm, for 5 min duration. Processed samples demonstrate high depth of refinement (DOR) and ultrafine grain size (0.43-1 µm) at high rotational speeds along with significant phase transformations from BCC/B2 to FCC microstructure. Further, surface free energy of the ultrafine-grain microstructure is enhanced up to 35%. Oxidation kinetics of the ultrafine-grained sample is decelerated up to 12-48% in a temperature range of 850-1050 °C for a duration of 100 h. Chromia and alumina were the predominant oxides formed in almost all the samples oxidized at elevated temperature. In addition, spinel Co(Cr,Fe)2O4/Fe(Co,Cr)2O4 formation is also detected in the unprocessed oxidized samples. Processed samples rich in grain boundaries (GBs) promote internal oxidation to form Al-rich inner oxides. The enhanced oxidation resistance of the processed samples is attributed to the microstructural refinement and homogenization resulting in the formation of protective chromia followed by Al-rich inner oxides.
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Inspired by many biological systems such as lotus leaves, insect wings and rose petals, great attention has been devoted to the study and fabrication of artificial superhydrophobic surfaces with multiple functionalities. In the present study, a simple and ecological synthesis route has been employed for large scale fabrication of self-assembled, sustainable nanostructures on unprocessed and micro imprinted aluminum surfaces named 'Nano' and 'Hierarchy'. The processed samples show extreme wettability ranging from superhydrophilicity to superhydrophobicity depending on post-processing conditions. The densely packed ellipsoidal nanostructures exhibited superhydrophobicity with excellent water, bacterial and dust repellency when modified by low surface energy material 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FOTES), characterized by a static contact angle of 163 ± 1° and contact angle hysteresis (CAH) ~3°. These coated surfaces show significant corrosion resistance with current density of 6 nA/cm2 which is 40 times lower than unprocessed counterpart and retain chemical stability after prolonged immersion in corrosive media. These surfaces show excellent self-cleaning ability with significantly low water consumption (< 0.1 µl/mm2-mg) and prevent biofouling which ensures its applicability in biological environment and marine components. The nanostructured superhydrophilic aluminum shows maximum antibacterial activity due to disruption of cell membrane. This work can offer a simple strategy to large scale fabrication of multifunctional biomimetic metallic surfaces.
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Incrustação Biológica , Nanoestruturas , Alumínio , Animais , Incrustação Biológica/prevenção & controle , Nanoestruturas/química , Propriedades de Superfície , MolhabilidadeRESUMO
Thermal spray coatings (TSCs) are widely utilized for limiting degradation of structural components. However, the performance of TSCs is significantly impaired by its inherent non-homogeneous microstructure, comprising of splat boundaries, porosities, secondary phase-formation, and elemental segregation. Herein, we report a simplistic approach for significantly enhancing the corrosion resistance of TSCs. Ni-Cr-5Al2O3 coatings were deposited on stainless steel using high-velocity oxy-fuel technique. The microstructure of as-sprayed coating showed significant inhomogeneities in the form of isolated splats and elemental segregation. The microstructure of developed coatings was modified using a novel processing technique, known as stationary friction processing (SFP). The SFP treatment resulted in complete refinement of coating microstructure with elimination of splat boundaries and pores along with elemental homogenization. The corrosion behavior of as-sprayed and SFP treated coating was evaluated in 3.5% NaCl solution using potentiodynamic polarization and electrochemical impedance spectroscopy. The SFP treatment reduced the corrosion rate of as-sprayed coating by an order of magnitude. Long-time immersion studies showed continuously decreasing impedance of the as-sprayed coating due to the penetration of the electrolyte along the splat boundaries. In contrast, impedance for the SFP treated coating increased with the immersion time due to the removal of all microstructural defects.
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Bioimplants are susceptible to simultaneous wear and corrosion degradation in the aggressive physiological environment. High entropy alloys with equimolar proportion of constituent elements represent a unique alloy design strategy for developing bioimplants due to their attractive mechanical properties, superior wear, and corrosion resistance. In this study, the tribo-corrosion behavior of an equiatomic MoNbTaTiZr high entropy alloy consisting of all biocompatible elements was evaluated and compared with 304 stainless steel as a benchmark. The high entropy alloy showed a low wear rate and a friction coefficient as well as quick and stable passivation in simulated body fluid. An increase from room temperature to body temperature showed excellent temperature assisted passivity and nobler surface layer of the high entropy alloy, resulting in four times better wear resistance compared to stainless steel. Stem cells and osteoblast cells displayed proliferation and migratory behavior, indicating in vitro biocompatibility. Several filopodia extensions on the cell periphery indicated early osteogenic commitment, and cell adhesion on the high entropy alloy. These results pave the way for utilizing the unique combination of tribo-corrosion resistance, excellent mechanical properties, and biocompatibility of MoNbTaTiZr high entropy alloy to develop bioimplants with improved service life and lower risk of implant induced cytotoxicity in the host body.
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Nanoscale patterns have dimensions that are comparable to the length scales affected by intermolecular and surface forces. In this study, we systematically investigated the individual roles of curvature, surface energy, lateral stiffness, material, and pattern density in the adhesion and friction of nanopatterns. We fabricated cylindrical and mushroom-shaped polymer pattern geometries containing flat- and round-topped morphologies using capillary force lithography and nanodrawing techniques. We showed that the curvature, surface energy, and density of the patterns predominantly influenced the adhesive interactions, whereas lateral stiffness dominated friction by controlling the geometrical interaction between the indenter and pillar during sliding. Interestingly, in contrast to previous studies, cylindrical and mushroom-shaped pillars showed similar adhesion characteristics but very different frictional properties. Using fracture mechanics analysis, we showed that this phenomenon is due to a larger ratio of the mushroom flange thickness (t) to the radius of the pillar stem (ρ), and we proposed a design criterion for mushroom patterns to exhibit a geckolike effect. The most important result of our work is the discovery of a linear master curve in the graph of adhesion versus friction for pillars with similar lateral stiffness values that is independent of curvature, material, surface energy, and pattern density. These results will aid in the identification of simple pattern parameters that can be scaled to tune adhesion and friction and will help broaden the understanding of nanoscale topographical interactions.