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1.
Artigo em Inglês | MEDLINE | ID: mdl-39098508

RESUMO

BACKGROUND: Non-infectious (inflammatory) cutaneous granulomatous disorders include cutaneous sarcoidosis (CS), granuloma annulare (GA), necrobiosis lipoidica (NL), and necrobiotic xanthogranuloma (NXG). These disorders share macrophage predominant inflammation histologically, but the inflammatory architecture and the pattern of extracellular matrix alteration varies. The underlying molecular explanations for these differences remain unclear. OBJECTIVE: To understand spatial gene expression characteristics in these disorders. METHODS: We performed spatial transcriptomics in cases of CS, GA, NL, and NXG to compare patterns of immune activation and other molecular features in a spatially resolved fashion. RESULTS: CS is characterized by a polarized, spatially organized T helper (Th) 1 predominant response with classical macrophage activation. GA is characterized by a mixed, but spatially organized pattern of Th1 and Th2 polarization with both classical and alternative macrophage activation. NL showed concomitant activation of Th1, Th2, and Th17 immunity with a mixed pattern of macrophage activation. Activation of type 1 immunity was shared among, CS, GA, and NL and included upregulation of IL-32. NXG showed upregulation of CXCR4-CXCL12/14 chemokine signaling and exaggerated alternative macrophage polarization. Histologic alteration of extracellular matrix correlated with hypoxia and glycolysis programs and type 2 immune activation. CONCLUSIONS: Inflammatory cutaneous granulomatous disorders show distinct and spatially organized immune activation that correlate with hallmark histologic changes.

2.
Ultramicroscopy ; 257: 113893, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38056396

RESUMO

The Weighted Burgers Vector (WBV) method can extract information about dislocation types and densities present in distorted crystalline materials from electron backscatter diffraction (EBSD) maps, using no assumptions about which slip systems might be present. Furthermore, high-angular resolution EBSD (HR-EBSD) uses a cross-correlation procedure to increase the angular precision of EBSD measurements by an order of magnitude compared to conventional EBSD. However, the WBV technique has not previously been applied to HR-EBSD data and therefore it remains unclear as to which low-angle substructures can be reliably characterised by WBV analysis of conventional EBSD data and which require additional HR-EBSD processing. To establish some practical examples that can be used to guide future data-acquisition strategies, we compare the output of the WBV method when applied to conventional EBSD data and HR-EBSD data collected from the most common minerals in Earth's lower crust (plagioclase feldspar) and upper mantle (olivine). The results demonstrate that HR-EBSD and WBV processing are complementary techniques. The increase in angular precision achieved with HR-EBSD processing allows low-angle (on the order of 0.1°) structures, which are obscured by noise in conventional EBSD data, to be analyzed quantitatively using the WBV method. Combining the WBV and HR-EBSD methods increases the precision of calculated WBV directions, which is essential when using information about active slip systems to infer likely deformation mechanisms from naturally deformed microstructures. This increase in precision is particularly important for low-symmetry crystals, such as plagioclase, that have a wide range of available slip systems that vary in relative activity with changing pressure, temperature and differential stress. Because WBV directions are calculated using no assumptions about which slip systems may be present, combining this technique with HR-EBSD to refine the precision of lattice orientation gradients is ideal for investigating complex natural materials with unknown deformation histories.

3.
J Synchrotron Radiat ; 31(Pt 1): 150-161, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117694

RESUMO

Third- and fourth-generation synchrotron light sources with high fluxes and beam energies enable the use of innovative X-ray translucent experimental apparatus. These experimental devices access geologically relevant conditions whilst enabling in situ characterization using the spatial and temporal resolutions accessible at imaging beamlines. Here, Heitt Mjölnir is introduced, a heated miniature triaxial rig based on the design of Mjölnir, but covering a wider temperature range and larger sample volume at similar pressure capacities. This device is designed to investigate coupled thermal, chemical, hydraulic and mechanical processes from grain to centimetre scales using cylindrical samples of 10 mm × 20 mm (diameter × length). Heitt Mjölnir can simultaneously reach confining (hydraulic) pressures of 30 MPa and 500 MPa of axial stress with independently controlled sample pore fluid pressure < 30 MPa. This internally heated apparatus operates to temperatures up to 573 K with a minimal vertical thermal gradient in the sample of <0.3 K mm-1. This new apparatus has been deployed in operando studies at the TOMCAT (Swiss Light Source), I12 JEEP (Diamond Light Source) and PSICHÉ (Synchrotron SOLEIL) beamlines for 4D X-ray microtomography with scan intervals of a few minutes. Heitt Mjölnir is portable and modular, allowing a wide range of 4D characterizations of low-grade metamorphism and deformational processes. It enables spatially and temporally resolved fluid-rock interaction studies at conditions of crustal reservoirs and is suitable for characterization of material properties in geothermal, carbonation or subsurface gas storage applications. Technical drawings and an operation guide are included in this publication.

4.
Forensic Sci Int ; 348: 111613, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36922254

RESUMO

Synthetic cannabinoids (SC) are extremely prevalent within the prison system and cause problems for prisoners, law enforcement and health services. SC are often soaked into paper then posted into prisons therefore one of the aims of this research is to collaborate with Rapiscan Systems Ltd. and local prisons in England to measure the effectiveness of trace detection methods for the indication of SC in prison post using the Itemiser 3E®. To ensure compounds did not go undetected, samples with Ion Trap Mobility Spectrometry™ peaks indicative of synthetic cannabinoids on the Itemiser 3E® were analysed using Gas Chromatography-Mass Spectrometry, Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy to identify chemical characteristics which allowed comparison to reference spectra. Sample data spanning three years from one prison's Itemiser 3E® were collated to identify trends in drug prevalence and the influence of library updates. To date, the method has identified four compounds: 5F-MDMB-PICA, MMB-4en-PICA, 4F-MDMB-BUTINACA and MDMB-4en-PINACA on prison post which were not already included on, or needed confirmatory analysis to update, the Itemiser 3E® library. As a result, the libraries on prison Itemiser 3E®s have been updated to ensure future detection of such compounds. Trends and influences from the processed Itemiser 3E® data were also reported back to the West Midlands Prison Group. This research directly benefitted both the West Midlands Prison Group and Rapiscan Systems Ltd. and it is anticipated that the continuation of this research could be expanded to a national scale.


Assuntos
Canabinoides , Drogas Ilícitas , Prisões , Drogas Ilícitas/análise , Canabinoides/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas
5.
Sci Justice ; 62(3): 336-348, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35598926

RESUMO

The mandatory introduction of ISO 17,025 accreditation to fingerprint comparisons forced changes to the documentation procedures. Academic and grey literature consistently suggest that the documentation should provide a sufficient auditable trail, yet there is some dissimilarity in the guidance relating to documentation content, and subjectivity with its interpretation. The accreditation body, UK Accreditation Service (UKAS), was not prescriptive in the methods required to produce working notes and were open to different practises, which has provided a useful opportunity to compare approaches to casework and to work with practitioners to inform effective practise. The research team carried out a gap analysis between pre-accreditation operational documentation practise and an ACE-V checklist, which was a summary of best practise guidance on documentation content. A white box study included thirty-one fingerprint examiners from six institutions, who were asked to undertake an 'Analysis' of eight friction ridge impressions. Participants were asked to produce working notes using their pre-accreditation documentation approach and a piece of software called 'PiAnoS', which prompted mark annotation and an assessment of mark quality. The notes were compared to the ACE-V checklist to determine which of the documentary suggestions were considered to obtain an understanding of experts' decision making. The results were used to develop a documentation strategy for an operational English fingerprint bureau, referred to as a "Mark Analysis Form". It consisted of content from the ACE-V checklist, supported by literature, and which received high response rates from experts alongside discussions by the research team to determine its relevance in the documentation strategy. The strategy met with the ISO 17,025 standard, evidenced by UKAS approval, and is currently used for casework.


Assuntos
Dermatoglifia , Documentação , Acreditação , Ciências Forenses , Humanos
6.
Cancer Chemother Pharmacol ; 89(4): 515-527, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35298699

RESUMO

PURPOSE: Preclinical characterization of cetrelimab (JNJ-63723283), a fully humanized immunoglobulin G4 kappa monoclonal antibody targeting programmed cell death protein-1 (PD-1), in human cancer models. METHODS: Cetrelimab was generated by phage panning against human and cynomolgus monkey (cyno) PD-1 extracellular domains (ECDs) and affinity maturation. Binding to primate and rodent PD-1 ECDs, transfected and endogenous cell-surface PD-1, and inhibition of ligand binding were measured. In vitro activity was evaluated using cytomegalovirus recall, mixed lymphocyte reaction, staphylococcal enterotoxin B stimulation, and Jurkat-PD-1 nuclear factor of activated T cell reporter assays. In vivo activity was assessed using human PD-1 knock-in mice implanted with MC38 tumors and a lung patient-derived xenograft (PDX) model (LG1306) using CD34 cord-blood-humanized NSG mice. Pharmacodynamics, toxicokinetics, and safety were assessed in cynos following single and/or repeat intravenous dosing. RESULTS: Cetrelimab showed high affinity binding to human (1.72 nM) and cyno (0.90 nM) PD-1 and blocked binding of programmed death-ligand 1 (PD-L1; inhibitory concentration [IC] 111.7 ng/mL) and PD-L2 (IC 138.6 ng/mL). Cetrelimab dose-dependently increased T cell-mediated cytokine production and stimulated cytokine expression. Cetrelimab 10 mg/kg reduced mean MC38 tumor volume in PD-1 knock-in mice at Day 21 (P < 0.0001) versus control. In a PDX lung model, 10 mg/kg cetrelimab (every 5 days for six cycles) increased frequency of peripheral T cells and reduced (P < 0.05) mean tumor volume versus control. Activity was consistent with that of established PD-1 inhibitors. Cetrelimab dosing was well tolerated in cynos and mean drug exposure increase was dose-dependent. CONCLUSION: Cetrelimab potently inhibits PD-1 in vitro and in vivo, supporting its clinical evaluation.


Assuntos
Anticorpos Monoclonais Humanizados , Anticorpos Monoclonais , Inibidores de Checkpoint Imunológico , Neoplasias , Receptor de Morte Celular Programada 1 , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Macaca fascicularis , Camundongos , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores
7.
Artigo em Inglês | MEDLINE | ID: mdl-34574668

RESUMO

With limited COVID-19-guidelines for institutions of higher education (IHEs), colleges and universities began the 2020-2021 academic year with varying approaches. We present a comprehensive COVID-19 prevention and mitigation approach at a residential university during the 2020-2021 academic year, along with campus SARS-CoV-2 transmission during this time. Risk management of COVID-19 was facilitated through (1) a layered approach of primary, secondary, and tertiary prevention measures; (2) a robust committee structure leveraging institutional public health expertise; (3) partnerships with external health entities; and (4) an operations system providing both structure and flexibility to adapt to changes in disease activity, scientific evidence, and public health guidelines. These efforts collectively allowed the university to mitigate SARS-CoV-2 transmission on campus and complete the academic year offering in-person learning on a residential campus. We identified 36 cases of COVID-19 among the 2037 in-person learners during the fall semester, 125 cases in the inter-semester break, and 169 cases among 2095 in-person learners during the spring semester. SARS-CoV-2 infection during the academic year was associated with gender (p = 0.04), race/ethnicity (p = 0.01), and sorority/fraternity membership (p < 0.01). Infection was not associated with undergraduate vs. graduate student status, Division I athlete status, or housing type (all p > 0.05). A multi-faceted public health approach was critical for reducing the impact of COVID-19 while carrying out the university's educational mission.


Assuntos
COVID-19 , Humanos , Gestão de Riscos , SARS-CoV-2 , Estudantes , Universidades
8.
Am J Forensic Med Pathol ; 42(3): 282-285, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33491949

RESUMO

ABSTRACT: Glyphosate is an organophosphorus compound and the active ingredient in commonly used herbicides, whereas polyoxyethyleneamine (POEA) is a nonionic surfactant often coupled with glyphosate in these herbicides to increase their efficacy. Cases of glyphosate-POEA ingestion have shown a variety of outcomes, ranging from skin and mucosal surface irritation to death. Here, we report mortality after ingestion of at least 237 mL of an herbicide confirmed to contain both glyphosate and POEA. The decedent's electronic medical record indicates presentation to the emergency department shortly after ingestion and rapid decompensation, with death occurring on the fourth day of admission. The autopsy report showed extensive pulmonary edema and congestion with no alimentary tract abnormalities. Microscopically, airway inflammation, edema, and hemorrhage were shown as well as pericentral necrosis and macrovascular hepatic steatosis. This case is unusual for several reasons including the fatal outcome in a young 30-year-old patient, the large volume of the herbicide consumed, the associated large volume aspirated, and the lung pathology associated with exposure to glyphosate-POEA since inhalation, and in this case, aspiration is an uncommon route of glyphosate-POEA exposure. This report therefore offers rare respiratory tract pathological findings and the clinical course after aspiration of a large volume of glyphosate-POEA.


Assuntos
Glicina/análogos & derivados , Herbicidas/intoxicação , Polietilenoglicóis/intoxicação , Suicídio Consumado , Tensoativos/intoxicação , Injúria Renal Aguda/induzido quimicamente , Adulto , Edema/patologia , Glicina/intoxicação , Hemorragia/patologia , Humanos , Fígado/patologia , Falência Hepática Aguda/induzido quimicamente , Pulmão/patologia , Masculino , Necrose , Edema Pulmonar/patologia , Insuficiência Respiratória/induzido quimicamente , Glifosato
9.
J Exp Med ; 218(3)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33433624

RESUMO

Although COVID-19 is considered to be primarily a respiratory disease, SARS-CoV-2 affects multiple organ systems including the central nervous system (CNS). Yet, there is no consensus on the consequences of CNS infections. Here, we used three independent approaches to probe the capacity of SARS-CoV-2 to infect the brain. First, using human brain organoids, we observed clear evidence of infection with accompanying metabolic changes in infected and neighboring neurons. However, no evidence for type I interferon responses was detected. We demonstrate that neuronal infection can be prevented by blocking ACE2 with antibodies or by administering cerebrospinal fluid from a COVID-19 patient. Second, using mice overexpressing human ACE2, we demonstrate SARS-CoV-2 neuroinvasion in vivo. Finally, in autopsies from patients who died of COVID-19, we detect SARS-CoV-2 in cortical neurons and note pathological features associated with infection with minimal immune cell infiltrates. These results provide evidence for the neuroinvasive capacity of SARS-CoV-2 and an unexpected consequence of direct infection of neurons by SARS-CoV-2.


Assuntos
Enzima de Conversão de Angiotensina 2 , Anticorpos Bloqueadores/química , COVID-19 , Córtex Cerebral , Neurônios , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/metabolismo , COVID-19/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Córtex Cerebral/virologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neurônios/metabolismo , Neurônios/patologia , Neurônios/virologia , Organoides/metabolismo , Organoides/patologia , Organoides/virologia
10.
bioRxiv ; 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32935108

RESUMO

Although COVID-19 is considered to be primarily a respiratory disease, SARS-CoV-2 affects multiple organ systems including the central nervous system (CNS). Yet, there is no consensus whether the virus can infect the brain, or what the consequences of CNS infection are. Here, we used three independent approaches to probe the capacity of SARS-CoV-2 to infect the brain. First, using human brain organoids, we observed clear evidence of infection with accompanying metabolic changes in the infected and neighboring neurons. However, no evidence for the type I interferon responses was detected. We demonstrate that neuronal infection can be prevented either by blocking ACE2 with antibodies or by administering cerebrospinal fluid from a COVID-19 patient. Second, using mice overexpressing human ACE2, we demonstrate in vivo that SARS-CoV-2 neuroinvasion, but not respiratory infection, is associated with mortality. Finally, in brain autopsy from patients who died of COVID-19, we detect SARS-CoV-2 in the cortical neurons, and note pathologic features associated with infection with minimal immune cell infiltrates. These results provide evidence for the neuroinvasive capacity of SARS-CoV2, and an unexpected consequence of direct infection of neurons by SARS-CoV-2.

11.
Nat Commun ; 11(1): 14, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31911583

RESUMO

Distorted olivines of enigmatic origin are ubiquitous in erupted products from a wide range of volcanic systems (e.g., Hawai'i, Iceland, Andes). Investigation of these features at Kilauea Volcano, Hawai'i, using an integrative crystallographic and chemical approach places quantitative constraints on mush pile thicknesses. Electron backscatter diffraction (EBSD) reveals that the microstructural features of distorted olivines, whose chemical composition is distinct from undistorted olivines, are remarkably similar to olivines within deformed mantle peridotites, but inconsistent with an origin from dendritic growth. This, alongside the spatial distribution of distorted grains and the absence of adcumulate textures, suggests that olivines were deformed within melt-rich mush piles accumulating within the summit reservoir. Quantitative analysis of subgrain geometry reveals that olivines experienced differential stresses of ∼3-12 MPa, consistent with their storage in mush piles with thicknesses of a few hundred metres. Overall, our microstructural analysis of erupted crystals provides novel insights into mush-rich magmatic systems.

12.
Proc Natl Acad Sci U S A ; 116(52): 26389-26393, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31826951

RESUMO

The lowermost portion of Earth's mantle (D″) above the core-mantle boundary shows anomalous seismic features, such as strong seismic anisotropy, related to the properties of the main mineral MgSiO3 postperovskite. But, after over a decade of investigations, the seismic observations still cannot be explained simply by flow models which assume dislocation creep in postperovskite. We have investigated the chemical diffusivity of perovskite and postperovskite phases by experiment and ab initio simulation, and derive equations for the observed anisotropic diffusion creep. There is excellent agreement between experiments and simulations for both phases in all of the chemical systems studied. Single-crystal diffusivity in postperovskite displays at least 3 orders of magnitude of anisotropy by experiment and simulation (Da = 1,000 Db; Db ≈ Dc) in zinc fluoride, and an even more extreme anisotropy is predicted (Da = 10,000 Dc; Dc = 10,000 Db) in the natural MgSiO3 system. Anisotropic chemical diffusivity results in anisotropic diffusion creep, texture generation, and a strain-weakening rheology. The results for MgSiO3 postperovskite strongly imply that regions within the D″ region of Earth dominated by postperovskite will 1) be substantially weaker than regions dominated by perovskite and 2) develop a strain-induced crystallographic-preferred orientation with strain-weakening rheology. This leads to strain localization and the possibility to bring regions with significantly varying textures into close proximity by strain on narrow shear zones. Anisotropic diffusion creep therefore provides an attractive alternative explanation for the complexity in observed seismic anisotropy and the rapid lateral changes in seismic velocities in D″.

13.
Talanta ; 205: 120056, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450388

RESUMO

Polymeric biguanides, as well as quaternary ammonium compounds, are ubiquitous antimicrobial agents in healthcare. Due to the highly cationic and polymeric nature of these compounds and the complex matrices in which they are found, the analytical characterization of products containing them remains challenging. In this work an efficient, sensitive, and high-resolution separation protocol was developed to perform quantitative measurements (sub-mg L-1) of alexidine dihydrochloride (ADH) and polyhexamethylene biguanide (PHMB) in commercial multipurpose contact lens solutions (MPS). Initially, contactless conductivity (C4D) detection was explored, but lacked adequate selectivity and sensitivity to quantify PHMB or ADH in commercial MPS. To overcome these limitations, an alternative approach using solid phase extraction (SPE) followed by separation with reversed phase ultra-performance liquid chromatography (RP-UPLC) was developed for both ADH and PHMB separation and detection. The most sensitive and reliable method investigated utilized standard additions to compensate for matrix effects. For ADH, concentration values measured with the presented method were consistent with data provided by the MPS manufacturer (1.6 mg L-1) within 0.10 mg L-1. PHMB quantification in MPS products was successful at concentrations <1 mg L-1 with quantitative reproducibility better than 2% RSD. Comparison of blind sample testing using the RP-UPLC method showed strong correlation (R2 = 0.939) of PHMB concentrations with results obtained by the United States Food and Drug Administration using a published HPLC-Evaporative light scattering detection (ELSD) assay. A significant advantage of this method is the ability to partially resolve PHMB polydispersity, which to date has been minimally studied and explained. By coupling with electrospray mass spectrometry (MS), a general trend was observed for increased retention as a function of PHMB chain length. The improved robustness and reproducibility of UV detection versus ELSD coupled with the superior resolving power of UPLC is an asset to the detection and characterization of PHMB and ADH. In addition to quality control of MPS, this method has potential application to the analyses skin wipes, wound dressings and other medical products where understanding how manufacturing processes lead to differences in polydispersity is important to maximize the antimicrobial properties while minimizing toxicologic effects.


Assuntos
Biguanidas/análise , Soluções para Lentes de Contato/análise , Eletroforese Capilar/métodos , Espectrometria de Massas/métodos , Cromatografia Líquida/métodos , Cromatografia de Fase Reversa , Desinfetantes/análise , Reprodutibilidade dos Testes , Extração em Fase Sólida
14.
Risk Anal ; 39(9): 2093-2112, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30822370

RESUMO

The future of energy mobility involves networks of users, operators, organizations, vehicles, charging stations, communications, materials, transportation corridors, points of service, and so on. The integration of smart grids with plug-in electric vehicle technologies has societal and commercial advantages that include improving grid stability, minimizing dependence on nonrenewable fuels, reducing vehicle emissions, and reducing the cost of electric vehicle ownership. However, ineffective or delayed participation of particular groups of stakeholders could disrupt industry plans and delay the desired outcomes. This article develops a framework to address enterprise resilience for two modes of disruptions-the first being the influence of scenarios on priorities and the second being the influence of multiple groups of stakeholders on priorities. The innovation of this study is to obtain the advantages of integrating two recent approaches: scenario-based preferences modeling and stakeholder mapping. Public agencies, grid operators, plug-in electric vehicle owners, and vehicle manufacturers are the four groups of stakeholders that are considered in this framework, along with the influence of four scenarios on priorities.

15.
Sci Rep ; 8(1): 4313, 2018 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-29511264

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

16.
Health Serv Res ; 53(2): 649-670, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28105639

RESUMO

OBJECTIVE: To analyze variation in medical care use attributable to Medicare's decentralized claims adjudication process as exemplified in home hemodialysis (HHD) therapy. DATA SOURCES/STUDY SETTING: Secondary data analysis using 2009-2012 paid Medicare claims for HHD and in-center hemodialysis (IHD). STUDY DESIGN: We compared variation across Medicare administrative contractors (MACs) in predicted paid treatments per standardized patient-month for HHD and IHD patients. We used ordinary least-squares regression to determine whether higher paid HHD treatment counts expanded HHD programs' presence among dialysis facilities. DATA COLLECTION: We identified HHD and IHD treatments using procedure, revenue center, and claim condition codes on type 72x claims. PRINCIPAL FINDINGS: MACs varied persistently in predicted HHD treatments per patient-month, ranging from 14.3 to 21.9 treatments versus 10.9 to 12.4 IHD treatments. The presence of facilities' HHD programs was uncorrelated with average HHD payment counts. CONCLUSIONS: Medicare's claims adjudication process promotes variation in medical care use, as we observe among HHD patients. MACs' discretionary decision making, while potentially facilitating innovation, may admit inefficiency in care practice as well as inequitable access to health care services. Regulators should weigh the benefits of flexibility in local coverage decisions against those of national standards for medical necessity.


Assuntos
Unidades Hospitalares de Hemodiálise/estatística & dados numéricos , Hemodiálise no Domicílio/estatística & dados numéricos , Reembolso de Seguro de Saúde/estatística & dados numéricos , Medicare/estatística & dados numéricos , Adulto , Idoso , Feminino , Gastos em Saúde , Unidades Hospitalares de Hemodiálise/economia , Hemodiálise no Domicílio/economia , Humanos , Reembolso de Seguro de Saúde/economia , Falência Renal Crônica/terapia , Masculino , Medicare/economia , Pessoa de Meia-Idade , Análise de Regressão , Estados Unidos
17.
Sci Rep ; 7(1): 14838, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29093572

RESUMO

The permeability of shales is important, because it controls where oil and gas resources can migrate to and where in the Earth hydrocarbons are ultimately stored. Shales have a well-known anisotropic directional permeability that is inherited from the depositional layering of sedimentary laminations, where the highest permeability is measured parallel to laminations and the lowest permeability is perpendicular to laminations. We combine state of the art laboratory permeability experiments with high-resolution X-ray computed tomography and for the first time can quantify the three-dimensional interconnected pathways through a rock that define the anisotropic behaviour of shales. Experiments record a physical anisotropy in permeability of one to two orders of magnitude. Two- and three-dimensional analyses of micro- and nano-scale X-ray computed tomography illuminate the interconnected pathways through the porous/permeable phases in shales. The tortuosity factor quantifies the apparent decrease in diffusive transport resulting from convolutions of the flow paths through porous media and predicts that the directional anisotropy is fundamentally controlled by the bulk rock mineral geometry. Understanding the mineral-scale control on permeability will allow for better estimations of the extent of recoverable reserves in shale gas plays globally.

18.
Sci Rep ; 7(1): 6881, 2017 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-28761137

RESUMO

Metamorphic reactions influence the evolution of the Earth's crust in a range of tectonic settings. For example hydrous mineral dehydration in a subducting slab can produce fluid overpressures which may trigger seismicity. During reaction the mechanisms of chemical transport, including water expulsion, will dictate the rate of transformation and hence the evolution of physical properties such as fluid pressure. Despite the importance of such processes, direct observation of mineral changes due to chemical transport during metamorphism has been previously impossible both in nature and in experiment. Using time-resolved (4D) synchrotron X-ray microtomography we have imaged a complete metamorphic reaction and show how chemical transport evolves during reaction. We analyse the dehydration of gypsum to form bassanite and H2O which, like most dehydration reactions, produces a solid volume reduction leading to the formation of pore space. This porosity surrounds new bassanite grains producing fluid-filled moats, across which transport of dissolved ions to the growing grains occurs via diffusion. As moats grow in width, diffusion and hence reaction rate slow down. Our results demonstrate how, with new insights into the chemical transport mechanisms, we can move towards a more fundamental understanding of the hydraulic and chemical evolution of natural dehydrating systems.

19.
Sci Rep ; 6: 36060, 2016 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-27824060

RESUMO

No standard treatment has been accepted widely for the first-/second-line therapy for advanced gastric cancer (AGC). The current study aimed to determine a preferred strategy between FOLFIRI (fluorouracil, leucovorin, and irinotecan) and ECX (epirubicin, cisplatin,and capecitabine) for AGC from the cost-effectiveness perspective. According to a French intergroup study, two groups (ECX arm and FOLFIRI arm) and three health states (progression-free survival (PFS), progressive disease (PD) and death) were analyzed in the current Markov model. All the medical costs were calculated from a Chinese societal perspective. Although FOLFIRI was an acceptable first-line therapy in the treatment of AGC with a better time-to treatment failure (TTF) compared to ECX, ECX arm (ECX followed by FOLFIRI) gained 0.08 quality-adjusted life months (QALMs) more effectiveness benefit compared with FOLFIRI arm (FOLFIRI followed by ECX). Additionally, a lower cost was found in ECX arm ($23,813.13 versus $24,983.70). Hence, the strategy of FOLFIRI arm is dominated by ECX arm ($4,125.8 per QALM in FOLIRI arm; $3,879.724 per QALM in ECX arm). ECX followed by FOLFIRI was a preferred strategy with more effectiveness and lower cost compared with FOLFIRI followed by ECX for the treatment of AGC.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/administração & dosagem , Antineoplásicos/economia , Análise Custo-Benefício , Tratamento Farmacológico/economia , Tratamento Farmacológico/métodos , Neoplasias Gástricas/tratamento farmacológico , China , Quimioterapia Combinada/economia , Quimioterapia Combinada/métodos , Humanos , Análise de Sobrevida , Resultado do Tratamento
20.
J Gastroenterol Hepatol ; 31(12): 1978-1985, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27118432

RESUMO

BACKGROUND AND AIM: Antiviral therapy has been demonstrated to significantly improve the survival in patients with advanced hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). The aim of the study was to investigate the cost-effectiveness of antiviral therapy in patients with advanced HBV-related HCC treated with sorafenib. METHODS: To conduct the analysis, a Markov model comprising three health states (progression-free survival, progressive disease, and death) was created. The efficacy data were derived from medical records. Cost data were collected based on the Chinese national drug prices. Utility data came from the previously published studies. One-way sensitivity analyses as well as probabilistic sensitivity analyses were performed to explore model uncertainties. RESULTS: In the base-case analysis, addition of antiviral therapy to sorafenib generated an effectiveness of 0.68 quality-adjusted life years (QALYs) at a cost of $25 026.04, while sorafenib monotherapy gained an effectiveness of 0.42 QALYs at a cost of $20 249.64. The incremental cost-effectiveness ratio (ICER) was $18 370.77/QALY for antiviral therapy group versus non-antiviral therapy group. On the other hand, the ICER between the two groups in patients with high or low HBV-DNA load, with or without cirrhosis, normal or elevated alanine aminotransferase/aspartate aminotransferase were $16 613.97/QALY, $19 774.16/QALY, $14 587.66/QALY, $19 873.84/QALY, $17 947.07/QALY, and $18 785.58/QALY, respectively. CONCLUSIONS: Based on the cost-effectiveness threshold ($20 301.00/QALY in China), addition of antiviral therapy to sorafenib is considered to be a cost-effective option compared with sorafenib monotherapy in patients with advanced HBV-related HCC in China from the patient's perspective.


Assuntos
Antineoplásicos/economia , Antineoplásicos/uso terapêutico , Antivirais/economia , Antivirais/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/economia , Custos de Medicamentos , Hepatite B/tratamento farmacológico , Hepatite B/economia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/economia , Niacinamida/análogos & derivados , Compostos de Fenilureia/economia , Compostos de Fenilureia/uso terapêutico , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , China , Análise Custo-Benefício , Progressão da Doença , Intervalo Livre de Doença , Feminino , Hepatite B/complicações , Hepatite B/mortalidade , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/virologia , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Modelos Econômicos , Niacinamida/economia , Niacinamida/uso terapêutico , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Estudos Retrospectivos , Sorafenibe , Fatores de Tempo , Resultado do Tratamento
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