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1.
Resuscitation ; 191: 109951, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37648146

RESUMO

INTRODUCTION: The optimum route for drug administration in cardiac arrest is unclear. Recent data suggest that use of the intraosseous route may be increasing. This study aimed to explore changes over time in use of the intraosseous and intravenous drug routes in out-of-hospital cardiac arrest in England. METHODS: We extracted data from the UK Out-of-Hospital Cardiac Arrest Outcomes registry. We included adult out-of-hospital cardiac arrest patients between 2015-2020 who were treated by an English Emergency Medical Service that submitted vascular access route data to the registry. The primary outcome was any use of the intraosseous route during cardiac arrest. We used logistic regression models to describe the association between time (calendar month) and intraosseous use. RESULTS: We identified 75,343 adults in cardiac arrest treated by seven Emergency Medical Service systems between January 2015 and December 2020. The median age was 72 years, 64% were male and 23% presented in a shockable rhythm. Over the study period, the percentage of patients receiving intraosseous access increased from 22.8% in 2015 to 42.5% in 2020. For each study-month, the odds of receiving any intraosseous access increased by 1.019 (95% confidence interval 1.019 to 1.020, p < 0.001). This observed effect was consistent across sensitivity analyses. We observed a corresponding decrease in use of intravenous access. CONCLUSION: In England, the use of intraosseous access in out-of-hospital cardiac arrest has progressively increased over time. There is an urgent need for randomised controlled trials to evaluate the clinical effectiveness of the different vascular access routes in cardiac arrest.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Adulto , Humanos , Masculino , Idoso , Feminino , Ambulâncias , Estudos de Coortes , Parada Cardíaca Extra-Hospitalar/tratamento farmacológico , Administração Intravenosa , Infusões Intraósseas , Sistema de Registros
2.
ACS Omega ; 8(13): 12592-12602, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37033864

RESUMO

One of the essential factors for water adsorption on silica gels is the concentration of silanol groups on the silica surface. However, no systematic investigation on the adsorption of sour gas components, methane (CH4), carbon dioxide (CO2), and hydrogen sulfide (H2S) on silica gels with different textural properties and surface silanol concentrations, has been conducted. Three silica gels of 22, 30, and 60 Å pore sizes, with silanol concentrations of αtotal = 2.516, 2.340, and 2.152 OH nm-2, respectively, were studied in this work. The adsorption data for CH4, CO2, H2S, and H2O at T = 0, 25, and 50 °C on the 22 and 30 Å pore size silica gels were presented, and a comparison of the data for the 60 Å pore size silica gel on the same adsorbates was conducted. All three silica gels showed an adsorption affinity in the order of H2O > H2S > CO2 > CH4. The isosteric heats of adsorption of H2O and H2S had a greater dependence on the silanol concentration than CO2 and CH4. At p < 10 bar, there was no difference in the adsorption per m2 of CH4 between the silica gels (n ads = 1.7 mmol m-2, for all silicas at p = 10 bar), while higher pressures resulted in greater adsorption capacity in the larger pore volume silica gels (at p = 20 bar: n ads = 3.0, 3.3, and 3.4 mmol m-2 for the 22, 30, and 60 Å pore size silicas, respectively). H2S adsorption at low pressures (p < 4 bar) was larger on the samples with larger silanol concentrations (at p = 3 bar: n ads = 6.1, 4.7, and 4.5 mmol m-2 for the 22, 30, and 60 Å pore size silicas, respectively), but above p = 4 bar, the 60 Å pore size silica had a greater adsorption capacity than the 30 Å pore size (at p = 5 bar: n ads = 8.0, 6.0, and 6.2 mmol m-2 for the 22, 30, and 60 Å pore size silicas, respectively).

3.
Nanomaterials (Basel) ; 11(7)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199059

RESUMO

In the past two decades, we have learned a great deal about self-assembly of dendritic metal oxide structures, partially inspired by the nanostructures mimicking the aesthetic hierarchical structures of ferns and corals. The self-assembly process involves either anisotropic polycondensation or molecular recognition mechanisms. The major driving force for research in this field is due to the wide variety of applications in addition to the unique structures and properties of these dendritic nanostructures. Our purpose of this minireview is twofold: (1) to showcase what we have learned so far about how the self-assembly process occurs; and (2) to encourage people to use this type of material for drug delivery, renewable energy conversion and storage, biomaterials, and electronic noses.

4.
Transfusion ; 61(10): 2885-2897, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34289101

RESUMO

BACKGROUND: Large volume delayed sampling (LVDS) and pathogen reduction technology (PRT) are strategies for platelet processing to minimize transfusion of contaminated platelet components (PCs). This study holistically compares the economic and clinical impact of LVDS and PRT in the United States. STUDY DESIGN AND METHODS: A decision model was constructed to simulate collection, processing, and use of PCs and to compare processing strategies: PRT with 5-day shelf life, LVDS with 7-day shelf life (LVDS7), and LVDS with 5-day shelf life extended to 7 days with secondary testing (LVDS5/2). Target population was adults requiring two or more transfusions. Collection, processing, storage, and distribution data were obtained from the National Blood Collection and Utilization Survey and published literature. Patient outcomes associated with transfusions were obtained from AABB guidelines, meta-analyses, and other published clinical studies. Costs were obtained from reimbursement schedules and other published sources. RESULTS: Given 10,000 donated units, 9512, 9511, and 9651 units of PRT, LVDS5/2, and LVDS7 PCs were available for transfusion, respectively. With these units, 1502, 2172, and 2329 transfusions can be performed with similar levels of adverse events. Assuming 30 transfusions a day, a hospital would require 69,325, 47,940, and 45,383 units of PRT, LVDS5/2, and LVDS7 platelets to perform these transfusions. The mean costs to perform transfusions were significantly higher with PRT units. CONCLUSIONS: Compared with PRT, LVDS strategies were associated with lower costs and higher PC availability while patients experienced similar levels of adverse events. Increased utilization of LVDS has the potential to improve efficiency, expand patient access to platelets, and reduce health care costs.


Assuntos
Plaquetas , Segurança do Sangue/métodos , Plaquetas/microbiologia , Plaquetas/parasitologia , Plaquetas/virologia , Segurança do Sangue/economia , Humanos , Contagem de Plaquetas , Transfusão de Plaquetas/economia , Transfusão de Plaquetas/métodos , Esterilização/economia , Esterilização/métodos , Estados Unidos
5.
Faraday Discuss ; 227: 125-140, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33295344

RESUMO

2-Dimensional (2D) metal oxides have many potential industrial applications including heterogeneous catalysis, water splitting, renewable energy conversion, supercapacitor applications, biomaterials, gas separation and gas storage. Herein we report a simple and scalable method for the preparation of 2D TiO2 nanostructures by reaction of titanium isopropoxide with acetic acid at 333 K in isopropanol, followed by calcination at 673 K to remove the organic ligands. Both the products and reaction intermediates have been studied using electron microscopy, X-ray diffraction, N2 physisorption, nuclear magnetic resonance, thermogravimetric analysis, and X-ray photoelectron, Raman, and infrared spectroscopy. The anisotropic condensation of the planar Ti6O4(OiPr)8(OAc)8 complex is believed to be responsible for the formation of the 2D structure, where OiPr and OAc represent isopropoxide and acetate ligands, respectively. This research demonstrates that the metal complexes are promising building blocks for desired architectures, and the self-assembly of an acetate bidentate ligand is a versatile tool for manipulating the shape of final products.

7.
Nanoscale ; 12(35): 17971-17981, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32705109

RESUMO

1D and 2D metal oxide nanostructures are important for potential applications in alternative energy, batteries, supercapacitors, catalysts, biomaterials, and electronic nanodevices. Many current approaches for making the desired nanomaterials require multiple steps, which are often exotic and complex for production on a commercial scale. In contrast, the sol-gel reactions between metal alkoxides and organic acids have emerged as a simple protocol for producing metal oxides and inorganic/organic hybrid materials with a controllable 1D or 2D architecture. Our knowledge of this process continues to evolve through the fundamental goal of designing a desired nanostructure from the corresponding molecular building blocks. Our research was driven by the discovery of various morphologies by fine-tuning the synthesis parameters, such as the reaction temperature and molar ratio of the reactants, as well as switching solvents. These discoveries lead to several quesions: What are the building blocks of the 1D and 2D nanostructures and how does the self-assembly occur? What are the reaction kinetics and the mechanisms of nanostructure formation? What role does the solvent play in the assembly process? What are the effects of reaction temperature and pressure? How can we manipulate the nanostructure-for example, the parallel growth of 1D semiconductors-from a substrate surface? And lastly, what are the industrial applications of macroporous aerogels and xerogels? This minireview will highlight documented research accounts to answer these questions.

8.
J Chem Phys ; 152(4): 044503, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32007074

RESUMO

Continued interest regarding the rheometric measurements of molten sulfur has persisted due to the need for industrial-scale transportation and handling of the material in a liquid phase. This has allowed for extended research developments to attain a fundamental understanding of the fluid. This work reports novel high temperature modulus data over the λ-transition region for liquid elemental sulfur, measured through the use of a modified Anton-Paar Modular Compact Rheometer 302. From these measurements, further insight was gained on the viscoelastic behavior and reptative relaxation times for liquid elemental sulfur. The slow relaxation time, τs, related to reptative behavior, was found to be between 0.24 s and 0.28 s at 190 °C. Utilizing the Maxwell relation, this was determined to correspond to an estimated viscosity range from 72 000 × 10-3 Pa s to 95 000 × 10-3 Pa s, which is in agreement with previous viscosity studies on liquid sulfur. A Cole-Cole plot of the experimental data also displayed characteristics of Debye-like relaxation, suggesting that the slow relaxation process was related to local S-S bond scission and recombination in sulfur chains and was not a relaxation coinciding with a polymeric chain mode. Finally, consecutive heating and cooling of the sulfur sample gave replicate values up to 210 °C on the third heating cycle, where an apparent structural change took place possibly due to cycling over the secondary transition, producing a thermal history, or sulfur reactions with trace impurities. This 210 °C temperature was found to have some recurrence within the literature.

9.
Wounds ; 31(10): 257-261, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31461401

RESUMO

INTRODUCTION: Delayed healing of pressure ulcers (PUs) in long-term care facilities (LTCFs) is associated with increased morbidity and expense. OBJECTIVE: The authors hypothesize that guideline-based, weekly coordinated care using specialized wound care surgeon-led bedside teams (SLBTs) may improve PU time-to-heal (TTH) outcomes when compared with usual care (UC). MATERIALS AND METHODS: Using a deidentified United States nationwide database, the authors retrospectively compared TTH outcomes of PUs diagnosed in LTCFs treated by either weekly SLBTs or UC. The SLBTs included an external specialized wound care surgeon (with or without a physician assistant and nurse practitioner) collaborating with facility nurses. Usual care was defined as all patient encounters not known to incorporate this team process. Variables assessed included patient age, gender, and comorbidities. The primary outcome measure was TTH; the TTH outcomes then were compared graphically and statistically between groups. Statistical significance was double-sided P ⟨ .05. RESULTS: In 2014, there were 39 459 consecutive PUs treated by UC and 5985 by SLBTs. The 5985 SLBT wounds originated from 3435 patients in 10 states and all geographic regions (mean age, 76.6 years; 55.9% female; 42.8% with hypertension; 23.7% with diabetes). The mean TTH for wounds managed by SLBTs was 47.5 days (median, 21 days) versus 69.0 days (median, 28 days) for wounds managed by UC, corresponding to an absolute TTH decrease of 21.5 days in wounds managed by SLBTs versus UC. Wounds managed by SLBTs also were significantly more likely to heal in less than 28 days (P ⟨ .0001). CONCLUSIONS: Pressure ulcers managed by coordinated nursing and weekly SLBTs appear to heal significantly faster than wounds managed by UC. Further studies are required to confirm these hypothesis-generating results.


Assuntos
Assistência de Longa Duração , Sistemas Automatizados de Assistência Junto ao Leito , Úlcera por Pressão/terapia , Cicatrização/fisiologia , Idoso , Feminino , Humanos , Masculino , Guias de Prática Clínica como Assunto , Úlcera por Pressão/patologia , Estudos Retrospectivos , Higiene da Pele , Cirurgiões
10.
Health Commun ; 34(12): 1524-1532, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30095286

RESUMO

The biomedical literature describes clearly the direct mechanisms influencing weight gain, but broader public discourse on the subject is rife with misleading claims about the factors that cause people to gain or lose weight. We examine how such misleading claims can dilute accurate information to the point that people arrive at poor judgments about the direct causes of weight gain. We adapt the conventional experimental paradigm used in dilution research (Nisbett, Zukier, & Lemley, 1981) to measure the effect of different information levels of dilution. We use a pair of online survey experiments to distinguish the effects of receiving distractingly plausible information versus raw information overload. These experiments also probe the limits of the dilution effect by using a large national sample of participants who vary by their health information efficacy and other potential moderators. Results suggest that public confusion about weight loss may stem from a dilution effect, which remains constant across a wide range of subgroups one might otherwise expect to resist it.


Assuntos
Informação de Saúde ao Consumidor/normas , Meios de Comunicação de Massa , Redução de Peso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoeficácia , Inquéritos e Questionários , Estados Unidos
11.
Curr Probl Pediatr Adolesc Health Care ; 48(7): 177-181, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30205944

RESUMO

Process maps are a key quality improvement tool used to visualize how healthcare, and its complex processes, are delivered. It is used for determining the step by step flow of the process, its timing, handoffs, and identifying outputs that can be visualized, measured, and studied. Due to the complexity of healthcare, process mapping must be a foundational element of both healthcare process design and quality improvement.


Assuntos
Atenção à Saúde/organização & administração , Pediatria/organização & administração , Garantia da Qualidade dos Cuidados de Saúde/normas , Melhoria de Qualidade/organização & administração , Algoritmos , Pesquisa sobre Serviços de Saúde , Humanos , Avaliação de Processos em Cuidados de Saúde
12.
Arch Dermatol Res ; 309(9): 739-748, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28889318

RESUMO

The study objectives were to demonstrate that glycerol, when topically applied from a roll-on antiperspirant formulation, can be delivered directly to human skin ex vivo and the axillary stratum corneum (SC) in vivo, and to assess whether it improves the quality of the axillary skin barrier. Ex vivo human skin absorption of glycerol was measured following application of a roll-on antiperspirant formulation containing 4% 13C3-glycerol. Skin distribution of 13C3-glycerol over 24 h was assessed using gas chromatography-mass spectrometry. In vivo axillary SC penetration was measured by confocal Raman spectroscopy and multivariate curve-resolution software 1 h after topical application of a roll-on antiperspirant formulation containing 8% deuterated glycerol (d5-glycerol). A clinical study was conducted to determine the efficacy of a roll-on antiperspirant formulation containing 4% glycerol in reducing shaving-induced visual irritation and in increasing axillary-skin hydration. Ex vivo skin absorption studies indicated that the formulation delivered 13C3-glycerol into the SC at all timepoints over the 24-h period. In vivo Raman measurements (1 h after application) demonstrated that d5-glycerol was detectable to a depth of at least 10 µm in the axillary SC. Application of 4% glycerol from a roll-on antiperspirant formulation to the axilla was associated with significantly less visible irritation and greater skin hydration than observed with the control (glycerol-free) product. These studies demonstrate that glycerol, incorporated in a roll-on antiperspirant formulation, is delivered directly and rapidly to all depths of the axillary SC, and results in improvements in visible irritation and hydration in the axilla.


Assuntos
Antiperspirantes/farmacologia , Glicerol/farmacologia , Pele/efeitos dos fármacos , Adulto , Método Duplo-Cego , Epiderme/efeitos dos fármacos , Feminino , Glicerol/administração & dosagem , Glicerol/farmacocinética , Humanos , Pessoa de Meia-Idade , Pele/metabolismo , Absorção Cutânea
13.
Langmuir ; 32(36): 9197-205, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27552141

RESUMO

Selective capture of thiols from a synthetic hydrogen sulfide containing mixture using supported nanogold materials has been explored for the potential removal of thiols from sour gas production fluids. In this research, TiO2-, Al2O3-, SiO2-, and ZnO-supported gold nanoparticles have been studied for their usage as regeneratable adsorbents to capture CH3SH, C2H5SH, and i-C3H7SH. Au/TiO2 and Au/Al2O3 showed promising properties for removing the thiols efficiently from a gas-phase mixture; however, Au/Al2O3 did catalyze some undesirable side reactions, e.g., carbonyl sulfide formation. It was found that a mild temperature of T = 200 °C was sufficient for regeneration of either Au/TiO2 or Au/Al2O3 adsorbent. The metal oxide mesopores played an important role for accommodating gold particles and chemisorption of the thiols, where smaller pore sizes were found to inhibit the agglomeration/growth of gold particles. The nature of thiol adsorption and the impact of multiple adsorption-desorption cycles on the adsorbents have been studied using electron microscopy, XPS, XRD, GC, and physi/chemiadsorption analyses.

14.
Biosci Rep ; 36(2)2016.
Artigo em Inglês | MEDLINE | ID: mdl-26934982

RESUMO

Iron is essential for the survival and virulence of pathogenic bacteria. The FeoB transporter allows the bacterial cell to acquire ferrous iron from its environment, making it an excellent drug target in intractable pathogens. The protein consists of an N-terminal GTP-binding domain and a C-terminal membrane domain. Despite the availability of X-ray crystal structures of the N-terminal domain, many aspects of the structure and function of FeoB remain unclear, such as the structure of the membrane domain, the oligomeric state of the protein, the molecular mechanism of iron transport, and how this is coupled to GTP hydrolysis at the N-terminal domain. In the present study, we describe the first homology model of FeoB. Due to the lack of sequence homology between FeoB and other transporters, the structures of four different proteins were used as templates to generate the homology model of full-length FeoB, which predicts a trimeric structure. We confirmed this trimeric structure by both blue-native-PAGE (BN-PAGE) and AFM. According to our model, the membrane domain of the trimeric protein forms a central pore lined by highly conserved cysteine residues. This pore aligns with a central pore in the N-terminal GTPase domain (G-domain) lined by aspartate residues. Biochemical analysis of FeoB from Pseudomonas aeruginosa further reveals a putative iron sensor domain that could connect GTP binding/hydrolysis to the opening of the pore. These results indicate that FeoB might not act as a transporter, but rather as a GTP-gated channel.


Assuntos
Proteínas de Bactérias/química , Proteínas de Transporte de Cátions/química , Modelos Moleculares , Pseudomonas aeruginosa/química , Domínios Proteicos , Estrutura Quaternária de Proteína
15.
J Phys Chem A ; 115(20): 5105-11, 2011 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-21526862

RESUMO

The rate coefficients for the reaction of 1,4-dioxane with atomic chlorine were measured from T = 292-360 K using the relative rate method. The reference reactant was isobutane and the experiments were made in argon with atomic chlorine produced by photolysis of small concentrations of Cl2. The rate coefficients were put on an absolute basis by using the published temperature dependence of the absolute rate coefficients for the reference reaction. The rate coefficients for the reaction of Cl with 1,4-dioxane were found to be independent of total pressure from p = 290 to 782 Torr. The experimentally measured rate coefficients showed a weak temperature dependence, given by k(exp)(T) = (8.4(-2.3)(+3.1)) × 10(-10) exp(-(470 ± 110)/(T/K)) cm3 molecule (-1) s(-1). The experimental results are rationalized in terms of statistical rate theory on the basis of molecular data obtained from quantum-chemical calculations. Molecular geometries and frequencies were obtained from MP2/aug-cc-pVDZ calculations, while single-point energies of the stationary points were computed at CCSD(T) level of theory. The calculations indicate that the reaction proceeds by an overall exothermic addition-elimination mechanism via two intermediates, where the rate-determining step is the initial barrier-less association reaction between the chlorine atom and the chair conformer of 1,4-dioxane. This is in contrast to the Br plus 1,4-dioxane reaction studied earlier, where the rate-determining step is a chair-to-boat conformational change of the bromine-dioxane adduct, which is necessary for this reaction to proceed. The remarkable difference in the kinetic behavior of the reactions of 1,4-dioxane with these two halogen atoms can be consistently explained by this change in the reaction mechanism.

16.
Ann Plast Surg ; 61(4): 425-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18812715

RESUMO

Time-tested treatments for chronic osteomyelitis involve prolonged courses of costly antibiotic treatment. Although such treatment remains unquestioned in acute osteomyelitis, it is an excessive regiment for chronic osteomyelitis. With appropriate surgical debridement and careful operative care, antibiotic treatment can be truncated in diagnoses of chronic osteomyelitis. This study represents the clinical practice of the pressure ulcer management program at Rancho Los Amigos National Rehabilitation Center in dealing with this difficult problem. One hundred fifty-seven patients with similar pressure ulcer wounds were studied retrospectively. Three groups of patients with pathologic diagnoses of acute osteomyelitis, chronic osteomyelitis, and negative osteomyelitis were compared for (1) postoperative stay, (2) wound infection, (3) wound breakdown requiring reoperation, and (4) same-site ulcer recurrence. In all cases, shallow bone shavings were sent for diagnosis via histologic study, and deep shavings were also sent to ensure adequate bone debridement and microbiologic study. All ulcers were subsequently closed with muscle and/or myocutaneous flaps. The negative and chronic osteomyelitis groups were treated with 5 to 7 days of IV antibiotics, whereas the acute group underwent a full 6-week course according to bone bacteriological culture and sensitivity. There was no statistical difference between the chronic osteomyelitis group and the control (negative) osteomyelitis group with respect to postoperative stay (70 days for chronic group, 72.4 for control), wound breakdown rate (10.7% for chronic, 10.2% for control), or ulcer recurrence (1.8% for chronic, 4.1 for control). The acute osteomyelitis group incurred longer hospital stays, greater incidence of wound breakdown, and statistically significantly greater ulcer recurrence (78.6 days, 13.2% and 17.0%, respectively). In cases of pressure ulcer management with bony involvement, bone pathologic diagnosis of chronic osteomyelitis allows for a shorter antibiotic course with better results when the offending tissue has been adequately debrided and closed with viable tissue flap coverage, than simple long-term (4-6 weeks) antibiotic treatment. Because of the extreme contaminated nature of these wounds, if such therapy works in these patients, it may be applicable to chronic osteomyelitis in more varied contaminated surgical cases involving bone.


Assuntos
Osteomielite/cirurgia , Úlcera por Pressão/complicações , Úlcera por Pressão/cirurgia , Traumatismos da Medula Espinal/complicações , Retalhos Cirúrgicos , Adulto , Doença Crônica , Resistência Microbiana a Medicamentos , Feminino , Seguimentos , Humanos , Tempo de Internação , Masculino , Osteomielite/etiologia , Osteomielite/patologia , Recidiva , Estudos Retrospectivos , Retalhos Cirúrgicos/efeitos adversos , Infecção da Ferida Cirúrgica/etiologia
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