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1.
Ther Innov Regul Sci ; 56(6): 948-963, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35182389

RESUMO

Listening to, and acting on, the voices of children and families during clinical research and innovation is fundamental to ensuring enhanced pediatric health care, medicines development, and technological advances. While this is often discussed as an important step in ensuring patient-centered care, involving children and families across the life cycle of clinical research is not currently routine. The pediatric research community needs to address how to meaningfully involve children and families if they are to succeed in designing clinical research that suits the needs of pediatric patients and their families. This paper describes how an international community working under the umbrella International Children's Advisory Network (iCAN) and European Young Person's Advisory Group Network (eYPAGnet) has involved children and families in the design and delivery of pediatric clinical research. It offers practical solutions through various case studies assessed against seven patient engagement quality criteria within the Patient Engagement Quality Guidance (PEQG) tool, highlighting some of the lessons learnt from involving and engaging with children and families across different stages of clinical research, including pediatric trials for drug development programs.


Assuntos
Pesquisa Biomédica , Participação do Paciente , Pediatria , Adolescente , Pesquisa Biomédica/tendências , Criança , Humanos , Assistência Centrada no Paciente
2.
J Contam Hydrol ; 222: 1-16, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30795856

RESUMO

Contaminants that are highly soluble in groundwater are rapidly transported via fractures in mechanically resistant sedimentary rock aquifers. Hence, a rigorous methodology is needed to estimate groundwater flow velocities in such fractured aquifers. Here, we propose an approach using borehole hydraulic testing to compute flow velocities in an un-faulted area of a fractured carbonate aquifer by applying the cubic law to a parallel plate model. The Cadeby Formation (Yorkshire, NE England) - a Permian dolostone aquifer present beneath the University of Leeds Farm - is the fractured aquifer selected for this hydraulic experiment. The bedding plane fractures of this dolostone aquifer, which are sub-horizontal, sub-parallel and laterally persistent, largely dominate the flow at shallow (<~40 mBGL) depths. These flowing bedding plane discontinuities are separated by a rock matrix which is relatively impermeable (Kwell-test/Kcore-plug~104) as is common in fractured carbonate aquifers. In the workflow reported here, the number of flowing fractures - mainly bedding plane fractures - intersecting three open monitoring wells are found from temperature/fluid conductivity and acoustic/optical televiewer logging. Following well installation, average fracture hydraulic apertures for screened intervals are found from analysis of slug tests. For the case study aquifer, this workflow predicts hydraulic apertures ranging from 0.10 up to 0.54 mm. However, groundwater flow velocities range within two order of magnitude from 13 up to 242 m/day. Notably, fracture apertures and flow velocities rapidly reduce with increasing depth below the water table; the upper ~10 m shows relatively high values of hydraulic conductivity (0.30-2.85 m/day) and corresponding flow velocity (33-242 m/day). Permeability development around the water table in carbonate aquifer-types is common, and arises where high pCO2 recharge water from the soil zone causes calcite/dolomite dissolution. Hence, agricultural contaminants entering the aquifer with recharge water are laterally transported rapidly within this upper part. Computation of groundwater flow velocities allows determination of the Reynolds number. Values of up ~1, indicating the lower limit of the transition from laminar to turbulent flow, are found at the studied site, which is situated away from major fault traces. Hence, turbulent flow is likely to arise in proximity to tectonic structures, such as normal faults, which localize flow and enhance karstification. The occurrence of turbulent flow in correspondence of such tectonic structures should be represented in regional groundwater flow simulations.


Assuntos
Água Subterrânea , Movimentos da Água , Carbonatos , Inglaterra , Poços de Água
3.
Sci Rep ; 8(1): 14190, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30242167

RESUMO

Mitochondria are central key players in cell metabolism, and mitochondrial DNA (mtDNA) instability has been linked to metabolic changes that contribute to tumorigenesis and to increased expression of pro-tumorigenic genes. Here, we use melanoma cell lines and metastatic melanoma tumors to evaluate the effect of mtDNA alterations and the expression of the mtDNA packaging factor, TFAM, on energetic metabolism and pro-tumorigenic nuclear gene expression changes. We report a positive correlation between mtDNA copy number, glucose consumption, and ATP production in melanoma cell lines. Gene expression analysis reveals a down-regulation of glycolytic enzymes in cell lines and an up-regulation of amino acid metabolism enzymes in melanoma tumors, suggesting that TFAM may shift melanoma fuel utilization from glycolysis towards amino acid metabolism, especially glutamine. Indeed, proliferation assays reveal that TFAM-down melanoma cell lines display a growth arrest in glutamine-free media, emphasizing that these cells rely more on glutamine metabolism than glycolysis. Finally, our data indicate that TFAM correlates to VEGF expression and may contribute to tumorigenesis by triggering a more invasive gene expression signature. Our findings contribute to the understanding of how TFAM affects melanoma cell metabolism, and they provide new insight into the mechanisms by which TFAM and mtDNA copy number influence melanoma tumorigenesis.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica/genética , Melanoma/genética , Melanoma/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Aminoácidos/genética , Aminoácidos/metabolismo , Carcinogênese/genética , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA/genética , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Regulação para Baixo/genética , Glutamina/genética , Glutamina/metabolismo , Glicólise/genética , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Regulação para Cima/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
4.
Am J Transplant ; 17(4): 1071-1080, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27639262

RESUMO

After extensive experimentation, outcomes of a first clinical normothermic machine perfusion (NMP) liver trial in the United Kingdom demonstrated feasibility and clear safety, with improved liver function compared with standard static cold storage (SCS). We present a preliminary single-center North American experience using identical NMP technology. Ten donor liver grafts were procured, four (40%) from donation after circulatory death (DCD), of which nine were transplanted. One liver did not proceed because of a technical failure with portal cannulation and was discarded. Transplanted NMP grafts were matched 1:3 with transplanted SCS livers. Median NMP was 11.5 h (range 3.3-22.5 h) with one DCD liver perfused for 22.5 h. All transplanted livers functioned, and serum transaminases, bilirubin, international normalized ratio, and lactate levels corrected in NMP recipients similarly to controls. Graft survival at 30 days (primary outcome) was not statistically different between groups on an intent-to-treat basis (p = 0.25). Intensive care and hospital stays were significantly more prolonged in the NMP group. This preliminary experience demonstrates feasibility as well as potential technical risks of NMP in a North American setting and highlights a need for larger, randomized studies.


Assuntos
Transplante de Fígado , Preservação de Órgãos/métodos , Perfusão/métodos , Complicações Pós-Operatórias , Isquemia Quente , Adolescente , Adulto , Idoso , Circulação Extracorpórea , Feminino , Sobrevivência de Enxerto , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Doadores de Tecidos , Adulto Jovem
5.
Am J Transplant ; 17(1): 42-53, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27862968

RESUMO

The 13th Banff Conference on Allograft Pathology was held in Vancouver, British Columbia, Canada from October 5 to 10, 2015. The cardiac session was devoted to current diagnostic issues in heart transplantation with a focus on antibody-mediated rejection (AMR) and small vessel arteriopathy. Specific topics included the strengths and limitations of the current rejection grading system, the central role of microvascular injury in AMR and approaches to semiquantitative assessment of histopathologic and immunophenotypic indicators, the role of AMR in the development of cardiac allograft vasculopathy, the important role of serologic antibody detection in the management of transplant recipients, and the potential application of new molecular approaches to the elucidation of the pathophysiology of AMR and potential for improving the current diagnostic system. Herein we summarize the key points from the presentations, the comprehensive, open and wide-ranging multidisciplinary discussion that was generated, and considerations for future endeavors.


Assuntos
Rejeição de Enxerto/patologia , Isoanticorpos/imunologia , Transplante de Órgãos/efeitos adversos , Guias de Prática Clínica como Assunto/normas , Rejeição de Enxerto/etiologia , Humanos , Isoanticorpos/sangue , Relatório de Pesquisa , Transplante Homólogo
6.
J Contam Hydrol ; 194: 36-58, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27969550

RESUMO

Sandstone aquifers are commonly assumed to represent porous media characterized by a permeable matrix. However, such aquifers may be heavy fractured when rock properties and timing of deformation favour brittle failure and crack opening. In many aquifer types, fractures associated with faults, bedding planes and stratabound joints represent preferential pathways for fluids and contaminants. In this paper, well test and outcrop-scale studies reveal how strongly lithified siliciclastic rocks may be entirely dominated by fracture flow at shallow depths (≤180m), similar to limestone and crystalline aquifers. However, sedimentary heterogeneities can primarily control fluid flow where fracture apertures are reduced by overburden pressures or mineral infills at greater depths. The Triassic St Bees Sandstone Formation (UK) of the East Irish Sea Basin represents an optimum example for study of the influence of both sedimentary and tectonic aquifer heterogeneities in a strongly lithified sandstone aquifer-type. This fluvial sedimentary succession accumulated in rapidly subsiding basins, which typically favours preservation of complete depositional cycles including fine grained layers (mudstone and silty sandstone) interbedded in sandstone fluvial channels. Additionally, vertical joints in the St Bees Sandstone Formation form a pervasive stratabound system whereby joints terminate at bedding discontinuities. Additionally, normal faults are present through the succession showing particular development of open-fractures. Here, the shallow aquifer (depth≤180m) was characterized using hydro-geophysics. Fluid temperature, conductivity and flow-velocity logs record inflows and outflows from normal faults, as well as from pervasive bed-parallel fractures. Quantitative flow logging analyses in boreholes that cut fault planes indicate that zones of fault-related open fractures characterize ~50% of water flow. The remaining flow component is dominated by bed-parallel fractures. However, such sub-horizontal fissures become the principal flow conduits in wells that penetrate the exterior parts of fault damage zones, as well as in non-faulted areas. The findings of this study have been compared with those of an earlier investigation of the deeper St Bees Sandstone aquifer (180 to 400m subsurface depth) undertaken as part of an investigation for a proposed nuclear waste repository. The deeper aquifer is characterized by significantly lower transmissivities. High overburden pressure and the presence of mineral infillings, have reduced the relative impact of tectonic heterogeneities on transmissivity here, thereby allowing matrix flow in the deeper part of the aquifer. The St Bees Sandstone aquifer contrasts the hydraulic behaviour of low-mechanically resistant sandstone rock-types. In fact, the UK Triassic Sandstone of the Cheshire Basin is low-mechanically resistant and flow is supported both by matrix and fracture. Additionally, faults in such weak-rocks are dominated by granulation seams representing flow-barriers which strongly compartmentalize the UK Triassic Sandstone in the Cheshire Basin.


Assuntos
Água Subterrânea , Hidrologia/métodos , Sedimentos Geológicos , Água Subterrânea/química , Minerais , Temperatura , Reino Unido , Movimentos da Água , Poços de Água
7.
Am J Transplant ; 16(1): 58-71, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26414799

RESUMO

Regulatory T cell (Treg)-based therapy is a promising approach to treat many immune-mediated disorders such as autoimmune diseases, organ transplant rejection, and graft-versus-host disease (GVHD). Challenges to successful clinical implementation of adoptive Treg therapy include difficulties isolating homogeneous cell populations and developing expansion protocols that result in adequate numbers of cells that remain stable, even under inflammatory conditions. We investigated the potential of discarded human thymuses, routinely removed during pediatric cardiac surgery, to be used as a novel source of therapeutic Tregs. Here, we show that large numbers of FOXP3(+) Tregs can be isolated and expanded from a single thymus. Expanded thymic Tregs had stable FOXP3 expression and long telomeres, and suppressed proliferation and cytokine production of activated allogeneic T cells in vitro. Moreover, expanded thymic Tregs delayed development of xenogeneic GVHD in vivo more effectively than expanded Tregs isolated based on CD25 expression from peripheral blood. Importantly, in contrast to expanded blood Tregs, expanded thymic Tregs remained stable under inflammatory conditions. Our results demonstrate that discarded pediatric thymuses are an excellent source of therapeutic Tregs, having the potential to overcome limitations currently hindering the use of Tregs derived from peripheral or cord blood.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Doença Enxerto-Hospedeiro/terapia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Linfócitos T Reguladores/imunologia , Timo/citologia , Adulto , Animais , Células Cultivadas , Criança , Feminino , Citometria de Fluxo , Doença Enxerto-Hospedeiro/imunologia , Humanos , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Homeostase do Telômero , Timo/imunologia , Timo/metabolismo
8.
Am J Transplant ; 16(5): 1548-58, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26602221

RESUMO

Organ transplantation from ABO blood group-incompatible (ABOi) donors requires accurate detection, effective removal and subsequent surveillance of antidonor antibodies. Because ABH antigen subtypes are expressed differently in various cells and organs, measurement of antibodies specific for the antigen subtypes in the graft is essential. Erythrocyte agglutination, the century-old assay used clinically, does not discriminate subtype-specific ABO antibodies and provides limited information on antibody isotypes. We designed and created an ABO-glycan microarray and demonstrated the precise assessment of both the presence and, importantly, the absence of donor-specific antibodies in an international study of pediatric heart transplant patients. Specific IgM, IgG, and IgA isotype antibodies to nonself ABH subtypes were detected in control participants and recipients of ABO-compatible transplants. Conversely, in children who received ABOi transplants, antibodies specific for A subtype II and/or B subtype II antigens-the only ABH antigen subtypes expressed in heart tissue-were absent, demonstrating the fine specificity of B cell tolerance to donor/graft blood group antigens. In contrast to the hemagglutination assay, the ABO-glycan microarray allows detailed characterization of donor-specific antibodies necessary for effective transplant management, representing a major step forward in precise ABO antibody detection.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Incompatibilidade de Grupos Sanguíneos/imunologia , Transplante de Coração , Tolerância Imunológica/imunologia , Isoanticorpos/imunologia , Polissacarídeos/imunologia , Linfócitos B/imunologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Seguimentos , Sobrevivência de Enxerto/imunologia , Humanos , Lactente , Recém-Nascido , Masculino , Análise em Microsséries , Prognóstico
9.
J Agric Sci ; 153(8): 1464-1478, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26500375

RESUMO

Findings from multi-year, multi-site field trial experiments measuring maize yield response to inoculation with the phosphorus-solubilizing fungus, Penicillium bilaiae Chalabuda are presented. The main objective was to evaluate representative data on crop response to the inoculant across a broad set of different soil, agronomic management and climate conditions. A statistical analysis of crop yield response and its variability was conducted to guide further implementation of a stratified trial and sampling plan. Field trials, analysed in the present study, were conducted across the major maize producing agricultural cropland of the United States (2005-11) comprising 92 small (with sampling replication) and 369 large (without replication) trials. The multi-plot design enabled both a determination of how sampling area affects the estimation of maize yield and yield variance and an estimation of the ability of inoculation with P. bilaiae to increase maize yield. Inoculation increased maize yield in 66 of the 92 small and 295 of the 369 large field trials (within the small plots, yield increased significantly at the 95% confidence level, by 0·17 ± 0·044 t/ha or 1·8%, while in the larger plots, yield increases were higher and less variable (i.e., 0·33 ± 0·026 t/ha or 3·5%). There was considerable inter-annual variability in maize yield response attributed to inoculation compared to the un-inoculated control, with yield increases varying from 0·7 ± 0·75 up to 3·7 ± 0·73%. No significant correlation between yield response and soil acidity (i.e., pH) was detected, and it appears that pH reduction (through organic acid or proton efflux) was unlikely to be the primary pathway for better phosphorus availability measured as increased yield. Seed treatment and granular or dribble band formulations of the inoculant were found to be equally effective. Inoculation was most effective at increasing maize yield in fields that had low or very low soil phosphorus status for both small and large plots. At higher levels of soil phosphorus, yield in the large plots increased more with inoculation than in the small plots, which could be explained by phosphorus fertilization histories for the different field locations, as well as transient (e.g., rainfall) and topographic effects.

10.
Am J Transplant ; 15(9): 2346-63, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25962413

RESUMO

The immature immune system is uniquely susceptible to tolerance induction and thus an attractive target for immunomodulation strategies for organ transplantation. Newborn mice injected with adult semi-allogeneic lymphohematopoietic cells accept transplants without immunosuppressive drugs. Early in vivo/in situ events leading to neonatal tolerance remain poorly understood. Here, we show by whole body/organ imaging that injected cells home to lymphoid organs and liver where various F1-donor cell types selectively alter neonatal immunity. In host thymus, F1-donor dendritic cells (DC) interact with developing thymocytes and regulatory T cells suggesting a role in negative selection. In spleen and lymph nodes, F1-donor regulatory T/B cells associate with host alloreactive cells and by themselves prolong cardiac allograft survival. In liver, F1-donor cells give rise to albumin-containing hepatocyte-like cells. The neonatal immune system is lymphopenic, Th-2 immunodeviated and contains immature DC, suggesting susceptibility to regulation by adult F1-donor cells. CD8a T cell inactivation greatly enhances chimerism, suggesting that variable emerging neonatal alloreactivity becomes a barrier to tolerance induction. This comprehensive qualitative imaging study systematically shows contribution of multiple in vivo processes leading simultaneously to robust tolerance. These insights into robust tolerance induction have important implications for development of strategies for clinical application.


Assuntos
Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Reação Hospedeiro-Enxerto/imunologia , Tolerância Imunológica/imunologia , Baço/transplante , Linfócitos T Reguladores/imunologia , Aloenxertos , Animais , Animais Recém-Nascidos , Microscopia Crioeletrônica , Sobrevivência de Enxerto/imunologia , Transplante de Coração , Ativação Linfocitária , Cooperação Linfocítica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Baço/imunologia , Timócitos/imunologia , Doadores de Tecidos
11.
Am J Transplant ; 15(10): 2602-15, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26014598

RESUMO

Blood group ABH(O) carbohydrate antigens are carried by precursor structures denoted type I-IV chains, creating unique antigen epitopes that may differ in expression between circulating erythrocytes and vascular endothelial cells. Characterization of such differences is invaluable in many clinical settings including transplantation. Monoclonal antibodies were generated and epitope specificities were characterized against chemically synthesized type I-IV ABH and related glycans. Antigen expression was detected on endomyocardial biopsies (n = 50) and spleen (n = 11) by immunohistochemical staining and on erythrocytes by flow cytometry. On vascular endothelial cells of heart and spleen, only type II-based ABH antigens were expressed; type III/IV structures were not detected. Type II-based ABH were expressed on erythrocytes of all blood groups. Group A1 and A2 erythrocytes additionally expressed type III/IV precursors, whereas group B and O erythrocytes did not. Intensity of A/B antigen expression differed among group A1 , A2 , A1 B, A2 B and B erythrocytes. On group A2 erythrocytes, type III H structures were largely un-glycosylated with the terminal "A" sugar α-GalNAc. Together, these studies define qualitative and quantitative differences in ABH antigen expression between erythrocytes and vascular tissues. These expression profiles have important implications that must be considered in clinical settings of ABO-incompatible transplantation when interpreting anti-ABO antibodies measured by hemagglutination assays with reagent erythrocytes.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Incompatibilidade de Grupos Sanguíneos/imunologia , Células Endoteliais/imunologia , Eritrócitos/imunologia , Transplante de Órgãos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Epidemiol Infect ; 143(12): 2588-95, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25519437

RESUMO

The US Center for Medicare and Medicaid Services (CMS) requires nursing homes and long-term-care facilities to document residents' vaccination status on the Resident Assessment Instrument (RAI). Vaccinating residents can prevent costly hospital admissions and deaths. CMS and public health officials use RAI data to measure vaccination rates in long-term-care residents and assess the quality of care in nursing homes. We assessed the accuracy of RAI data against medical records in 39 nursing homes in Florida, Georgia, and Wisconsin. We randomly sampled residents in each home during the 2010-2011 and 2011-2012 influenza seasons. We collected data on receipt of influenza vaccination from charts and RAI data. Our final sample included 840 medical charts with matched RAI records. The agreement rate was 0·86. Using the chart as a gold standard, the sensitivity of the RAI with respect to influenza vaccination was 85% and the specificity was 77%. Agreement rates varied within facilities from 55% to 100%. Monitoring vaccination rates in the population is important for gauging the impact of programmes and policies to promote adherence to vaccination recommendations. Use of data from RAIs is a reasonable approach for gauging influenza vaccination rates in nursing-home residents.


Assuntos
Instituição de Longa Permanência para Idosos/estatística & dados numéricos , Influenza Humana/prevenção & controle , Casas de Saúde/estatística & dados numéricos , Registros/normas , Vacinação/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Centers for Medicare and Medicaid Services, U.S./legislação & jurisprudência , Feminino , Florida , Georgia , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Registros/legislação & jurisprudência , Sensibilidade e Especificidade , Estados Unidos , Wisconsin
13.
Transplant Proc ; 46(5): 1601-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24935334

RESUMO

INTRODUCTION: Most studies investigating machine perfusion preservation for heart transplantation perfuse through the aortic root (antegrade), but the coronary sinus (retrograde) is a potential option. We hypothesized that retrograde machine perfusion provides better functional protection than static storage, while avoiding the potential irregular perfusion seen when aortic insufficiency occurs with antegrade perfusion. MATERIALS AND METHODS: Eighteen canine donor hearts were arrested, procured, and stored in modified Celsior solution for 4 hours by using either static storage at 0°C to 4°C (n = 6) or machine perfusion preservation at 5°C via the aortic root (antegrade, n = 6) or coronary sinus (retrograde, n = 6). Lactate and myocardial oxygen consumption were measured in perfused hearts. Hearts were reimplanted and reperfused for 6 hours with hourly function calculated by using the preload recruitable stroke work (PRSW) relation. Myocardial water content was determined at the end of the experiment. RESULTS: Storage lactate levels and myocardial oxygen consumption were comparable in both perfused groups. The PRSW was increased immediately after bypass in the antegrade group (120.6 ± 19.1 mm Hg) compared with the retrograde (75.0 ± 11.3 mm Hg) and static (78.1 ± 10.5 mm Hg) storage groups (P < .05). At the end of reperfusion, PRSW was higher in the retrograde group (69.8 ± 7.4 mm Hg) compared with the antegrade (40.1 ± 6.8 mm Hg) and static (39.9 ± 10.9 mm Hg) storage groups (P < .05). Myocardial water content was similar among groups. CONCLUSIONS: Both antegrade and retrograde perfusion demonstrated excellent functional preservation, at least equivalent to static storage. Initial function was superior in the antegrade group, but the retrograde hearts displayed better function late after reperfusion. Neither perfused group developed significant edema. Machine perfusion preservation is a promising technique for improving results of cardiac transplantation.


Assuntos
Transplante de Coração/veterinária , Animais , Cães , Soluções para Preservação de Órgãos , Consumo de Oxigênio , Perfusão
14.
J Contam Hydrol ; 147: 96-111, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23501945

RESUMO

A multi-borehole pumping and tracer test in fractured chalk is revisited and reinterpreted in the light of fractional flow. Pumping test data analyzed using a fractional flow model gives sub-spherical flow dimensions of 2.2-2.4 which are interpreted as due to the partially penetrating nature of the pumped borehole. The fractional flow model offers greater versatility than classical methods for interpreting pumping tests in fractured aquifers but its use has been hampered because the hydraulic parameters derived are hard to interpret. A method is developed to convert apparent transmissivity and storativity (L(4-n)/T and S(2-n)) to conventional transmissivity and storativity (L2/T and dimensionless) for the case where flow dimension, 2

Assuntos
Carbonato de Cálcio , Água Subterrânea , Modelos Teóricos , Movimentos da Água , Hidrologia , Porosidade
16.
Artigo em Inglês | MEDLINE | ID: mdl-21784675

RESUMO

OBJECTIVE: The aim of this study was to investigate the use of field emission scanning electron microscopy and electron dispersive spectrography (SEM-EDS) to identify silver solder "tattoo." STUDY DESIGN: SEM-EDS was used to analyze material present in the connective tissue of a patient who presented with bilateral pigmentation of the mandibular lingual gingiva adjacent to the first molars. No dental restorations were present. RESULTS: SEM-EDS analysis identified silver, with no evidence of tin, copper, or mercury. The patient was wearing an orthodontic appliance where brackets had been soldered to the archwire with silver solder. It is hypothesed that the solder underwent electrolytic corrosion with subsequent regrouping of silver ions in the submucosa leading to blue-gray discoloration. CONCLUSION: Spectrography proved to be a powerful diagnostic tool in identifying the metal within the oral mucosa. Attention is drawn to this newly described lesion, which should be included as a differential diagnosis for pigmented oral mucosal lesions.


Assuntos
Soldagem em Odontologia , Doenças da Boca/induzido quimicamente , Mucosa Bucal/efeitos dos fármacos , Transtornos da Pigmentação/induzido quimicamente , Prata/efeitos adversos , Tatuagem , Adolescente , Corrosão , Eletrólise , Microanálise por Sonda Eletrônica , Feminino , Humanos , Microscopia Eletrônica de Varredura , Doenças da Boca/patologia , Mucosa Bucal/ultraestrutura , Braquetes Ortodônticos , Fios Ortodônticos , Transtornos da Pigmentação/patologia
17.
J Environ Qual ; 40(2): 312-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21520737

RESUMO

Attenuation of rainfall within the solum may help to move contaminants and nutrients into the soil to be better sequestered or utilized by crops. Surface application of phosphorus (P) amendments to grasslands may lead to elevated concentrations of P in surface runoff and eutrophication of surface waters. Aeration of grasslands has been proposed as a treatment to reduce losses of applied P. Here, results from two small-plot aeration studies and two field-scale, paired-watershed studies are supplemented with previously unpublished soil P data and synthesized. The overall objective of these studies was to determine the impact of aeration on soil P, runoff volume, and runoff P losses from mixed tall fescue [Lolium arundinaceum (Schreb.) Darbysh.]-bermudagrass (Cynodon dactylon L.) grasslands fertilized with P. Small-scale rainfall simulations were conducted on two soil taxa using three types of aeration implements: spikes, disks, and cores. The-field scale study was conducted on four soil taxa with slit and knife aeration. Small-plot studies showed that core aeration reduced loads of total P and dissolved reactive P (DRP) in runoff from plots fertilized with broiler litter and that aeration was effective in reducing P export when it increased soil P in the upper 5 cm. In the field-scale study, slit aeration reduced DRP losses by 35% in fields with well-drained soils but not in poorly drained soils. Flow-weighted concentrations of DRP in aerated fields were related to water-soluble P applied in amendments and soil test P in the upper 5 cm. These studies show that the overall effectiveness of mechanical soil aeration on runoff volume and P losses is controlled by the interaction of soil characteristics such as internal drainage and compaction, soil P, type of surface-applied manure, and type of aeration implement.


Assuntos
Agricultura/instrumentação , Agricultura/métodos , Fertilizantes , Fósforo/metabolismo , Poaceae , Solo , Movimentos da Água
18.
Appl Radiat Isot ; 69(6): 834-43, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21388817

RESUMO

This paper describes the development of methods for the rapid screening of gross alpha (GA) and gross beta (GB) radioactivity in liquid foods, specifically, Tang drink mix, apple juice, and milk, as well as screening of GA, GB, and gamma radioactivity from surface deposition on apples. Detailed procedures were developed for spiking of matrices with (241)Am (alpha radioactivity), (90)Sr/(90)Y (beta radioactivity), and (60)Co, (137)Cs, and (241)Am (gamma radioactivity). Matrix stability studies were performed for 43 days after spiking. The method for liquid foods is based upon rapid digestion, evaporation, and flaming, followed by gas proportional (GP) counting. For the apple matrix, surface radioactivity was acid-leached, followed by GP counting and/or gamma spectrometry. The average leaching recoveries from four different apple brands were between 63% and 96%, and have been interpreted on the basis of ion transport through the apple cuticle. The minimum detectable concentrations (MDCs) were calculated from either the background or method-blank (MB) measurements. They were found to satisfy the required U.S. FDA's Derived Intervention Levels (DILs) in all but one case. The newly developed methods can perform radioactivity screening in foods within a few hours and have the potential to capacity with further automation. They are especially applicable to emergency response following accidental or intentional contamination of food with radioactivity.


Assuntos
Partículas alfa , Métodos Analíticos de Preparação de Amostras/métodos , Contaminação Radioativa de Alimentos/análise , Raios gama , Malus/química , Radioisótopos/análise , Radioisótopos/química , Bebidas/análise , Calibragem , Radioisótopos de Césio/análise , Radioisótopos de Cobalto/análise , Digestão , Emergências , Malus/efeitos da radiação , Radioatividade , Espectrometria gama/métodos , Radioisótopos de Estrôncio/análise , Radioisótopos de Ítrio/análise
19.
Transplant Proc ; 42(5): 1591-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20620480

RESUMO

OBJECTIVE: Machine perfusion preservation has been used experimentally to extend the storage interval of donor hearts. We previously demonstrated that machine perfusion with glucose-supplemented Celsior preservation solution led to superior reperfusion function but resulted in increased myocardial edema compared with conventional static preservation. We hypothesized that other solutions that contain an oncotic agent, such as University of Wisconsin Machine Perfusion Solution (UWMPS), might reduce graft edema development while maintaining myocardial oxidative metabolism during long-term storage. METHODS: Canine hearts were stored and perfused in a perfusion preservation device (LifeCradle; Organ Transport Systems) after cardioplegic arrest and donor cardiectomy. Hearts were perfused either with glucose-supplemented Celsior (which lacks an oncotic agent) or UWMPS (which contains hydroxyethyl starch) at 5 degrees C in the perfusion device over 10 hours. Oxygen consumption (MVO(2)), lactate accumulation, regional flow distribution, and myocardial water content were measured. RESULTS: Hearts in both groups continued to extract oxygen over the entire perfusion interval. Lactate accumulation was minimal in both groups. Both solutions delivered perfusate evenly to all regions of myocardium. Heart weight increase (Celsior 31.3 +/- 4.3%, UWMPS -3.3 +/- 1.9%) and final myocardial water content (Celsior 80.2 +/- 1.3%, UWMPS 75.9 +/- 0.3%) were higher in the Celsior group (P < .005). CONCLUSIONS: Donor hearts can be supported by a perfusion device over relatively extended storage intervals. These organs continue to undergo oxidative metabolism with little lactate accumulation. An oncotic agent appears to be important in limiting increases in myocardial water content. UWMPS appears to be superior for perfusion preservation of myocardium by reducing edema development during storage.


Assuntos
Edema Cardíaco/prevenção & controle , Transplante de Coração/fisiologia , Soluções para Preservação de Órgãos/química , Soluções para Preservação de Órgãos/farmacologia , Perfusão/métodos , Adenosina/farmacologia , Alopurinol/farmacologia , Animais , Água Corporal/metabolismo , Dissacarídeos/farmacologia , Cães , Eletrólitos/farmacologia , Glutamatos/farmacologia , Glutationa/farmacologia , Coração/anatomia & histologia , Coração/fisiologia , Transplante de Coração/métodos , Histidina/farmacologia , Insulina/farmacologia , Manitol/farmacologia , Tamanho do Órgão , Consumo de Oxigênio/efeitos dos fármacos , Rafinose/farmacologia
20.
Am J Transplant ; 10(2): 389-97, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20041867

RESUMO

ABO-blood group incompatible infant heart transplantation has had excellent short-term outcomes. Uncertainties about long-term outcomes have been a barrier to the adoption of this strategy worldwide. We report a nonrandomized comparison of clinical outcomes over 10 years of the largest cohort of ABO-incompatible recipients. ABO-incompatible (n = 35) and ABO-compatible (n = 45) infant heart transplantation recipients (< or =14 months old, 1996-2006) showed no important differences in pretransplantation characteristics. There was no difference in incidence of and time to moderate acute cellular rejection. Despite either the presence (seven patients) or development (eight patients) of donor-specific antibodies against blood group antigens, in only two ABO-incompatible patients were these antibodies implicated in antibody-mediated rejection (which occurred early posttransplantation, was easily managed and did not recur in follow-up). Occurrence of graft vasculopathy (11%), malignancy (11%) and freedom from severe renal dysfunction were identical in both groups. Survival was identical (74% at 7 years posttransplantation). ABO-blood group incompatible heart transplantation has excellent outcomes that are indistinguishable from those of the ABO-compatible population and there is no clinical justification for withholding this lifesaving strategy from all infants listed for heart transplantation. Further studies into observed differing responses in the development of donor-specific isohemagglutinins and the implications for graft accommodation are warranted.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Anticorpos/imunologia , Transplante de Coração/imunologia , Transplante de Coração/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica , Bleomicina , Antígenos de Grupos Sanguíneos/imunologia , Criança , Rejeição de Enxerto/imunologia , Hemaglutininas/imunologia , Humanos , Lactente , Metotrexato , Pediatria , Doadores de Tecidos/estatística & dados numéricos , Resultado do Tratamento , Vincristina
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