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1.
J Stroke Cerebrovasc Dis ; 33(8): 107739, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38703876

RESUMO

BACKGROUND: There is a deficiency in the evidence from rural and regional centres in Australia on the weekend effect following presentation with acute stroke. OBJECTIVE: To estimate the association between admission over a weekend/holiday and all-cause mortality 3-day, 7-day, 14-day, 1-month, 3-month, 6-month, and 12-month following acute stroke. METHODS: The records of stroke patients admitted to a main regional hospital in Australia from 2010 to 2020 were linked with the National Death Index. Time to death following ischaemic, haemorrhagic, and total stroke at different time points was modelled using Weibull, Exponential, or Gompertz regression based on best model fit determined by Akaike's information criterion. RESULTS: Of 1669 patients, 1273 (76.3%) were admitted on a weekday, and 396 (23.7%) on a weekend/ or holiday. After adjusting for age, sex, and Charlson Comorbidity Index, stroke type and country of birth, admissions over a weekend/holiday following total stroke were significantly associated with an increased risk of dying within three days from admission [hazard ratio (HR): 1.59, 95% confidence interval: 1.01-2.50]. In haemorrhagic stroke, increased risk of death was significantly higher at three days (HR: 2.19, 95% confidence interval: 1.17-4.08), 14 days (HR: 1.73, 95% confidence interval: 1.02-2.93), and 1 month (HR: 1.82, 95% confidence interval: 1.09-3.03) following admission on the weekend/ or holiday compared to those admitted during the weekdays. CONCLUSIONS: This study reports a short-term adverse weekend/holiday effect following admission for haemorrhagic stroke or total stroke. No significant weekend/holiday effect was found in ischaemic stroke.

2.
Ultramicroscopy ; 258: 113909, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38157689

RESUMO

Research investigating the interface between biological organisms and nanomaterials nowadays requires multi-faceted microscopic methods to elucidate the interaction mechanisms and effects. Here we describe a novel approach and methodology correlating data from an atomic force microscope inside a scanning electron microscope (AFM-in-SEM). This approach is demonstrated on bacteria-diamond-metal nanocomposite samples relevant in current life science research. We describe a procedure for preparing such multi-component test samples containing E. coli bacteria and chitosan-coated hydrogenated nanodiamonds decorated with silver nanoparticles on a carbon-coated gold grid. Microscopic topography information (AFM) is combined with chemical, material, and morphological information (SEM using SE and BSE at varied acceleration voltages) from the same region of interest and processed to create 3D correlative probe-electron microscopy (CPEM) images. We also establish a novel 3D RGB color image algorithm for merging multiple SE/BSE data from SEM with the AFM surface topography data which provides additional information about microscopic interaction of the diamond-metal nanocomposite with bacteria, not achievable by individual analyses. The methodology of CPEM data interpretation is independently corroborated by further in-situ (EDS) and ex-situ (micro-Raman) chemical characterization as well as by force volume AFM analysis. We also discuss the broader applicability and benefits of the methodology for life science research.

3.
Pregnancy Hypertens ; 28: 162-167, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35490442

RESUMO

BACKGROUND: Hypertensive disorders of pregnancy (HDP) are associated with an increased risk of long-term cardiovascular, cerebrovascular, and adverse renal outcomes. Biomarkers including soluble fms-like tyrosine kinase 1 (sFlt1), placental growth factor (PlGF) are predictive of the development of preeclampsia. Their long-term value in predicting which women will develop cardiovascular complications remote from pregnancy is not yet established. OBJECTIVES: To determine the prevalence and incidence of Cardio-renal-metabolic outcomes at 10 years follow-up in a cohort of women screened for suspected preeclampsia from 2008 to 2009 and assess the relationship between pregnancy biomarkers and long-term outcomes. STUDY DESIGN: A retrospective cohort study of 117 women. Outcomes were assessed by auditing medical records. The primary outcome was the prevalence of cardiovascular, cerebrovascular, metabolic and renal outcomes at 10 years remote from the diagnosis of HDP. The secondary outcome was to assess the relationship of the remote from pregnancy outcomes to biomarkers (sFlt1, PlGF, soluble endoglin (sEng) and neutrophil gelatinase associated lipocalin (NGAL)) taken at the time of pregnancy comparing the results of those with adverse outcomes compared to those without. RESULTS: There was a 12.7% prevalence of cardiovascular and cerebrovascular disease, 44.4% prevalence of hypertension, 20.6% prevalence of chronic kidney disease and 17.5% prevalence of diabetes. Women who developed preeclampsia had an increased prevalence and incidence of adverse outcomes compared to women without preeclampsia. There was a weak relationship between sENg measured at the time of clinical suspicion of preeclampsia and the adverse outcomes 144 (139-146) months remote from pregnancy. CONCLUSIONS: Biomarkers taken at the time of pregnancy did not accurately predict the long-term adverse cardiometabolic outcomes.


Assuntos
Hipertensão Induzida pela Gravidez , Nefropatias , Pré-Eclâmpsia , Biomarcadores , Feminino , Humanos , Hipertensão Induzida pela Gravidez/epidemiologia , Fator de Crescimento Placentário , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/epidemiologia , Gravidez , Prevalência , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular
4.
Int J Nanomedicine ; 16: 3541-3554, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34079247

RESUMO

PURPOSE: Nanomaterials for antimicrobial applications have gained interest in recent years due to the increasing bacteria resistance to conventional antibiotics. Wound sterilization, water treatment and surface decontamination all avail from multifunctional materials that also possess excellent antibacterial properties, eg zinc oxide (ZnO). Here, we assess and compare the effects of synthesized hedgehog-like ZnO structures and commercial ZnO particles with and without mixing on the inactivation of bacteria on surfaces and in liquid environments. METHODS: Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria in microbial culture medium were added to reverse spin bioreactors that contained different concentrations of each ZnO type to enable dynamic mixing of the bacteria-ZnO suspensions. Optical density of the bacteria-ZnO suspensions was measured in real-time and the number of viable bacteria after 24 h exposure was determined using standard microbiological techniques. The concentration of zinc ion generated from ZnO dissolution in different liquid types was estimated from the dynamic interaction exposure. Static antibacterial tests without agitation in liquid media and on agar surface were performed for comparison. RESULTS: A correlation between increasing ZnO particle concentration and reduction in viable bacteria was not monotonous. The lowest concentration tested (10 µg/mL) even stimulated bacteria growth. The hedgehog ZnO was significantly more antibacterial than commercial ZnO particles at higher concentrations (up to 1000 µg/mL tested), more against E. coli than S. aureus. Minimum inhibitory concentration in microwell plates was correlated with those results. No inhibition was detected for any ZnO type deposited on agar surface. Zinc ion release was greatly suppressed in cultivation media. Scanning electron microscopy images revealed that ZnO needles can pierce membrane of bacteria whereas the commercial ZnO nanoparticles rather agglomerate on the cell surface. CONCLUSION: The inhibition effects are thus mainly controlled by the interaction dynamics between bacteria and ZnO, where mixing greatly enhances antibacterial efficacy of all ZnO particles. The efficacy is modulated also by ZnO particle shapes, where hedgehog ZnO has superior effect, in particular at lower concentrations. However, at too low concentrations, ZnO can stimulate bacteria growth and must be thus used with caution.


Assuntos
Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Ouriços , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Testes de Sensibilidade Microbiana
5.
J Nurs Adm ; 47(12): 592-596, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29135846

RESUMO

Contemporary CNOs are committed to developing the next generation of nurse leaders. At OhioHealth, the nursing strategic vision includes the belief that every nurse will be a leader in improving health across the care continuum. In 2016, the OhioHealth System partnered with AONE to participate in the Care Innovation and Transformation program resulting in bedside nurses living this strategic vision and creating positive changes in quality, safety, and satisfaction for patients and families.


Assuntos
Liderança , Serviço Hospitalar de Enfermagem/organização & administração , Supervisão de Enfermagem/organização & administração , Admissão e Escalonamento de Pessoal/organização & administração , Desenvolvimento de Pessoal/organização & administração , Humanos , Melhoria de Qualidade , Estados Unidos
6.
Nano Lett ; 17(3): 1336-1343, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28139927

RESUMO

We demonstrate an entirely new method of nanoparticle chemical synthesis based on liquid droplet irradiation with ultralow (<0.1 eV) energy electrons. While nanoparticle formation via high energy radiolysis or transmission electron microscopy-based electron bombardment is well-understood, we have developed a source of electrons with energies close to thermal which leads to a number of important and unique benefits. The charged species, including the growing nanoparticles, are held in an ultrathin surface reaction zone which enables extremely rapid precursor reduction. In a proof-of-principle demonstration, we obtain small-diameter Au nanoparticles (∼4 nm) with tight control of polydispersity, in under 150 µs. The precursor was almost completely reduced in this period, and the resultant nanoparticles were water-soluble and free of surfactant or additional ligand chemistry. Nanoparticle synthesis rates within the droplets were many orders of magnitude greater than equivalent rates reported for radiolysis, electron beam irradiation, or colloidal chemical synthesis where reaction times vary from seconds to hours. In our device, a stream of precursor loaded microdroplets, ∼15 µm in diameter, were transported rapidly through a cold atmospheric pressure plasma with a high charge concentration. A high electron flux, electron and nanoparticle confinement at the surface of the droplet, and the picoliter reactor volume are thought to be responsible for the remarkable enhancement in nanoparticle synthesis rates. While this approach exhibits considerable potential for scale-up of synthesis rates, it also offers the more immediate prospect of continuous on-demand delivery of high-quality nanomaterials directly to their point of use by avoiding the necessity of collection, recovery, and purification. A range of new applications can be envisaged, from theranostics and biomedical imaging in tissue to inline catalyst production for pollution remediation in automobiles.

7.
Chemosphere ; 144: 879-87, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26421628

RESUMO

Carbonaceous materials like biochars are increasingly recognized as effective sorbent materials for sequestering organic pollutants. Here, we study sorption behavior of two common hydrophobic organic contaminants 2,2',5,5'-tetrachlorobiphenyl (CB52) and phenanthrene (PHE), on biochars and other carbonaceous materials (CM) produced at a wide range of conditions and temperatures from various feedstocks. The primary aim was to establish structure-reactivity relationships responsible for the observed variation in CM and biochar sorption characteristics. CM were characterized for their elemental composition, surface area, pore size distribution, aromaticity and thermal stability. Freundlich sorption coefficients for CB52 and PHE (i.e. LogK(F,CB52) and K(F,PHE), respectively) to CM showed a variation of two to three orders of magnitude, with LogK(F,CB52) ranging from 5.12 ± 0.38 to 8.01 ± 0.18 and LogK(F,PHE) from 5.18 ± 0.09 to 7.42 ± 1.09. The highest LogK(F) values were observed for the activated CM, however, non-activated biochars produced at high temperatures (>700 °C) sorbed almost as strongly (within 0.2-0.5 Log units) as the activated ones. Sorption coefficients significantly increased with pyrolysis temperature, CM surface area and pore volume, aromaticity, and thermal stability, and decreased with H/C, O/C, (O + N)/C content. The results of our study contribute to the understanding of processes underlying HOC sorption to CM and explore the potential of CM as engineered sorbents for environmental applications.


Assuntos
Carvão Vegetal/química , Poluentes Ambientais/isolamento & purificação , Fenantrenos/isolamento & purificação , Bifenilos Policlorados/isolamento & purificação , Adsorção , Poluentes Ambientais/química , Interações Hidrofóbicas e Hidrofílicas , Fenantrenos/química , Bifenilos Policlorados/química , Relação Estrutura-Atividade , Propriedades de Superfície , Temperatura
9.
Environ Sci Technol ; 47(14): 7704-12, 2013 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-23758057

RESUMO

Suppression of nitrous oxide (N2O) emissions from soil is commonly observed after amendment with biochar. The mechanisms accounting for this suppression are not yet understood. One possible contributing mechanism is N2O sorption to biochar. The sorption of N2O and carbon dioxide (CO2) to four biochars was measured in an anhydrous system with pure N2O. The biochar data were compared to those for two activated carbons and other components potentially present in soils-uncharred pine wood and peat-and five inorganic metal oxides with variable surface areas. Langmuir maximum sorption capacities (Qmax) for N2O on the pine wood biochars (generated between 250 and 500 °C) and activated carbons were 17-73 cm(3) g(-1) at 20 °C (median 51 cm(3) g(-1)), with Langmuir affinities (b) of 2-5 atm(-1) (median 3.4 atm(-1)). Both Qmax and b of the charred materials were substantially higher than those for peat, uncharred wood, and metal oxides [Qmax 1-34 cm(3) g(-1) (median 7 cm(3) g(-1)); b 0.4-1.7 atm(-1) (median 0.7 atm(-1))]. This indicates that biochar can bind N2O more strongly than both mineral and organic soil materials. Qmax and b for CO2 were comparable to those for N2O. Modeled sorption coefficients obtained with an independent polyparameter-linear free-energy relationship matched measured data within a factor 2 for mineral surfaces but underestimated by a factor of 5-24 for biochar and carbonaceous surfaces. Isosteric enthalpies of sorption of N2O were mostly between -20 and -30 kJ mol(-1), slightly more exothermic than enthalpies of condensation (-16.1 kJ mol(-1)). Qmax of N2O on biochar (50000-130000 µg g(-1) biochar at 20 °C) exceeded the N2O emission suppressions observed in the literature (range 0.5-960 µg g(-1) biochar; median 16 µg g(-1)) by several orders of magnitude. Thus, the hypothesis could not be falsified that sorption of N2O to biochar is a mechanism of N2O emission suppression.


Assuntos
Carvão Vegetal , Compostos Inorgânicos/química , Óxido Nitroso/química , Compostos Orgânicos/química , Água/química , Modelos Teóricos , Termodinâmica , Madeira/química
11.
J Paediatr Child Health ; 48(7): 582-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22429646

RESUMO

AIM: Children account for approximately half of the humanitarian refugees currently resettled in Australia. A multidisciplinary refugee health clinic (RHC) was established at the tertiary paediatric hospital in Western Australia to address burgeoning referrals of refugee children following voluntary post-resettlement health assessment. The aim of this study is to describe the epidemiology of common conditions in resettled paediatric refugees attending a tertiary multidisciplinary RHC. METHODS: Standardised clinical and demographic data were routinely collected during first visit clinical assessment at the RHC. Descriptive analyses of the first 1026 children are presented. RESULTS: One thousand twenty-six refugee children from 475 families and over 30 different ethnicities were described. Nine hundred twenty-seven (90.4%) children were referred following post-resettlement health assessment. Median age was 7.8 years. Common reasons for referral were: vitamin D deficiency (400, 39%), iron deficiency (226, 22%), positive Helicobacter pylori serology (206, 21%), poor appetite (175, 17.1%), and schistosomiasis (170, 16.6%). Comorbidities identified by the RHC included tinea capitis and corporis (297, 28.9%), and dental disease (228, 22.2%). Two-thirds of children (680, 66.3%) had at least one abnormal finding on clinical examination that identified pathologies that were not evident from the history. Three hundred eighty children (37%) were referred to sub-specialty services. CONCLUSIONS: A multidisciplinary paediatric RHC facilitated and strengthened the management of refugee children with multiple and complex health needs. Evidenced-based culturally appropriate methods to identify developmental delay, psychological morbidity and quantify social needs of this vulnerable population remain uncertain. These findings are relevant to the continuing evolution of paediatric refugee health care in Australia and other high income countries.


Assuntos
Instituições de Assistência Ambulatorial/estatística & dados numéricos , Nível de Saúde , Refugiados/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Deficiências Nutricionais/etnologia , Atenção à Saúde , Países Desenvolvidos , Feminino , Humanos , Lactente , Infecções/etnologia , Masculino , Austrália Ocidental/epidemiologia
12.
Environ Sci Technol ; 46(5): 2830-8, 2012 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-22321025

RESUMO

Biochar soil amendment is advocated to mitigate climate change and improve soil fertility. A concern though, is that during biochar preparation PAHs and dioxins are likely formed. These contaminants can possibly be present in the biochar matrix and even bioavailable to exposed organisms. Here we quantify total and bioavailable PAHs and dioxins in a suite of over 50 biochars produced via slow pyrolysis between 250 and 900 °C, using various methods and biomass from tropical, boreal, and temperate areas. These slow pyrolysis biochars, which can be produced locally on farms with minimum resources, are also compared to biochar produced using the industrial methods of fast pyrolysis and gasification. Total concentrations were measured with a Soxhlet extraction and bioavailable concentrations were measured with polyoxymethylene passive samplers. Total PAH concentrations ranged from 0.07 µg g(-1) to 3.27 µg g(-1) for the slow pyrolysis biochars and were dependent on biomass source, pyrolysis temperature, and time. With increasing pyrolysis time and temperature, PAH concentrations generally decreased. These total concentrations were below existing environmental quality standards for concentrations of PAHs in soils. Total PAH concentrations in the fast pyrolysis and gasification biochar were 0.3 µg g(-1) and 45 µg g(-1), respectively, with maximum levels exceeding some quality standards. Concentrations of bioavailable PAHs in slow pyrolysis biochars ranged from 0.17 ng L(-1) to 10.0 ng L(-1)which is lower than concentrations reported for relatively clean urban sediments. The gasification produced biochar sample had the highest bioavailable concentration (162 ± 71 ng L(-1)). Total dioxin concentrations were low (up to 92 pg g(-1)) and bioavailable concentrations were below the analytical limit of detection. No clear pattern of how strongly PAHs were bound to different biochars was found based on the biochars' physicochemical properties.


Assuntos
Carvão Vegetal/química , Dioxinas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Disponibilidade Biológica , Carbono/análise , Meio Ambiente , Hidrogênio/análise , Oxigênio/análise
14.
Appl Spectrosc ; 62(2): 182-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18284794

RESUMO

Fires in terrestrial ecosystems produce large amounts of charcoal that persist in the environment and represent a substantial pool of sequestered carbon in soil. The objective of this research was to investigate the effect of charring on mid-infrared spectra of materials likely to be present in forest fires in order to determine the feasibility of determining charred organic matter in soils. Four materials (cellulose, lignin, pine bark, and pine wood) and char from these materials, created by charring for various durations (1 to 168 h) and at various temperatures (200 to 450 degrees C), were studied. Mid-infrared spectra and measures of acidity (total acids, carboxylic acids, lactones, and phenols as determined by titration) were determined for 56 different samples (not all samples were charred at all temperatures/durations). Results showed spectral changes that varied with the material, temperature, and duration of charring. Despite the wide range of spectral changes seen with the differing materials and length/temperature of charring, partial least squares calibrations for total acids, carboxylic acids, lactones, and phenols were successfully created (coefficient of determination and root mean squared deviation of 0.970 and 0.380; 0.933 and 0.227; 0.976 and 0.120; and 0.982 and 0.101 meq/g, respectively), indicating that there is a sufficient commonality in the changes to develop calibrations without the need for unique calibrations for each specific material or condition of char formation.


Assuntos
Celulose/química , Carvão Vegetal/análise , Lignina/química , Casca de Planta/química , Solo/análise , Madeira/química , Incêndios , Pinus ponderosa/química , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Water Res ; 39(4): 549-58, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15707627

RESUMO

A certain amount of wood char or soot in a soil or sediment sample may cause the sorption of organic compounds to deviate significantly from the linear partitioning commonly observed with soil organic matter (SOM). Laboratory produced and field wood chars have been obtained and analyzed for their sorption isotherms of a model solute (phenanthrene) from water solution. The uptake capacities and nonlinear sorption effects with the laboratory wood chars are similar to those with the field wood chars. For phenanthrene aqueous concentrations of 1 microg l(-1), the organic carbon-normalized sorption coefficients (log K(oc)) ranging from 5.0 to 6.4 for field chars and 5.4-7.3 for laboratory wood chars, which is consistent with literature values (5.6-7.1). Data with artificial chars suggest that the variation in sorption potential can be attributed to heating temperature and starting material, and both the quantity and heterogeneity of surface-area impacts the sorption capacity. These results thus help to corroborate and explain the range of logK(oc) values reported in previous research for aquifer materials containing wood chars.


Assuntos
Carbono/química , Carvão Vegetal/química , Fenantrenos/química , Poluentes Químicos da Água/análise , Adsorção , Animais , Sedimentos Geológicos/química , Compostos Orgânicos/química , Fenantrenos/análise , Solo/análise , Temperatura , Madeira
17.
Environ Health Perspect ; 111(3): 305-8, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12611659

RESUMO

An unblinded crossover study of fenitrothion 0.18 mg/kg/day [36 times the acceptable daily intake (ADI)] and 0.36 mg/kg/day (72 X ADI) administered as two daily divided doses for 4 days in 12 human volunteers was designed and undertaken after results from a pilot study. On days 1 and 4, blood and urine samples were collected for analysis of fenitrothion and its major metabolites, as well as plasma and red blood cell cholinesterase activities, and biochemistry and hematology examination. Pharmacokinetic parameters could only be determined at the higher dosage, as there were insufficient measurable fenitrothion blood levels at the lower dosage and the fenitrooxone metabolite could not be measured. There was a wide range of interindividual variability in blood levels, with peak levels achieved between 1 and 4 hr and a half-life for fenitrothion of 0.8-4.5 hr. Although based on the half-life, steady-state levels should have been achieved; the area under the curve (AUC)(0-12 hr) to AUC(0-(infinity) )ratio of 1:3 suggested accumulation of fenitrothion. There was no significant change in plasma or red blood cell cholinesterase activity with repeated dosing at either dosage level of fenitrothion, and there were no significant abnormalities detected on biochemical or hematologic monitoring.


Assuntos
Fenitrotion/farmacocinética , Fenitrotion/toxicidade , Inseticidas/farmacocinética , Inseticidas/toxicidade , Administração Oral , Adulto , Colinesterases/farmacologia , Estudos Cross-Over , Relação Dose-Resposta a Droga , Feminino , Fenitrotion/administração & dosagem , Meia-Vida , Humanos , Inseticidas/administração & dosagem , Masculino , Pessoa de Meia-Idade , Distribuição Tecidual
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