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1.
J Adv Nurs ; 79(11): 4228-4237, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37548346

ABSTRACT

AIM: In the context of widening societal diversity, culturally and linguistically diverse patients continue to experience inequities in healthcare access and deficiencies in standards of nursing care. Re-framing culturally responsive care as a complex intervention spanning multiple interacting factors at micro, meso and macro levels is an essential prerequisite for addressing knowledge translation gaps into everyday nursing practice. To this end, this paper proposes and explicates the potential of applying synergistic participatory implementation methodologies for developing effective implementation strategies with impact at individual and wider structural levels. DESIGN: Discussion Paper. DATA SOURCES: A co-design case study is presented as an example of combining normalization process theory and participatory learning and action to investigate and support the implementation of culturally responsive care in general practice nursing. IMPLICATIONS FOR NURSING: Enacting culturally responsive health care is inherently complex in that it is influenced by multiple interacting factors. Viewing culturally responsive care as a complex intervention and incorporating a synergistic participatory implementation science approach offers possibilities for addressing the documented shortcomings in the implementation of culturally responsive nursing care. CONCLUSION: There is a need to move away from conventional approaches to conceptualizing and generating evidence on culturally responsive care. Incorporating participatory implementation methodologies can provide a new lens to investigate and support whole system implementation strategies. IMPACT: The combination of participatory and implementation methodologies is both theoretically and empirically informed. Engaging stakeholders in the co-design and co-production of evidence and solutions to long standing problems has the potential to increase the likelihood of influencing iterative and sustainable implementation and changes to clinical practice and systems. PATIENT OR PUBLIC CONTRIBUTION: This work is part of a wider programme of participatory health research on migrant health, partnering with a non-governmental organization that supports migrants.


Subject(s)
Community-Based Participatory Research , Transients and Migrants , Humans , Implementation Science , Health Services Accessibility , Learning
2.
Science ; 366(6469): 1143-1149, 2019 11 29.
Article in English | MEDLINE | ID: mdl-31780560

ABSTRACT

Disruption of intestinal microbial communities appears to underlie many human illnesses, but the mechanisms that promote this dysbiosis and its adverse consequences are poorly understood. In patients who received allogeneic hematopoietic cell transplantation (allo-HCT), we describe a high incidence of enterococcal expansion, which was associated with graft-versus-host disease (GVHD) and mortality. We found that Enterococcus also expands in the mouse gastrointestinal tract after allo-HCT and exacerbates disease severity in gnotobiotic models. Enterococcus growth is dependent on the disaccharide lactose, and dietary lactose depletion attenuates Enterococcus outgrowth and reduces the severity of GVHD in mice. Allo-HCT patients carrying lactose-nonabsorber genotypes showed compromised clearance of postantibiotic Enterococcus domination. We report lactose as a common nutrient that drives expansion of a commensal bacterium that exacerbates an intestinal and systemic inflammatory disease.


Subject(s)
Enterococcus/growth & development , Gastrointestinal Microbiome , Graft vs Host Disease/microbiology , Hematopoietic Stem Cell Transplantation , Lactose/metabolism , Aged , Animals , Dysbiosis , Enterococcus/genetics , Enterococcus/metabolism , Feces/microbiology , Female , Gastrointestinal Microbiome/genetics , Humans , Intestines/microbiology , Male , Mice , Microbiota , Middle Aged , RNA, Ribosomal, 16S , Sequence Analysis, RNA , Transplantation, Homologous
3.
Pharmeur Bio Sci Notes ; 2018: 112-123, 2018.
Article in English | MEDLINE | ID: mdl-30272557

ABSTRACT

The European Pharmacopoeia (Ph. Eur.) pertussis toxin (PT) Biological Reference Preparation (BRP) is used as a working standard for safety testing of acellular pertussis vaccines as prescribed in the Ph. Eur. monographs 1356 "Pertussis vaccine (acellular, component, adsorbed)" and 1595 "Pertussis vaccine (acellular, co-purified, adsorbed)". The BRP was calibrated in 2006 in the murine histamine sensitisation test (HIST) against the World Health Organization (WHO) 1st International Standard (IS) for PT. In recent years, there have been increasing efforts to replace the in vivo test with in vitro methods. The Chinese hamster ovary (CHO) cell clustering assay has been used for many years by manufacturers to monitor residual PT activity in detoxified non-adjuvanted bulks. More recently a standardised protocol has been developed for this assay and a PT reference preparation was needed. Due to low stocks, the WHO 1st International Standard for Pertussis Toxin (JNIH-5) needed to be replaced and therefore a joint study between the European Directorate for the Quality of Medicines & HealthCare (EDQM) and WHO was initiated to calibrate the PT BRP for the CHO clustering assay and to replace the IS. The collaborative study involved 14 laboratories from Europe, North America and Asia. The outcome of the study confirmed that the BRP is suitable for use as a reference preparation in the CHO clustering assay. The material was assigned a potency of 1360 IU per vial for the CHO clustering assay.


Subject(s)
Animal Testing Alternatives , Biological Assay/standards , Pertussis Toxin/analysis , Pertussis Vaccine/standards , Pharmacopoeias as Topic/standards , Animals , CHO Cells , Calibration , Cell Survival/drug effects , Cricetinae , Cricetulus , Europe , International Cooperation , Laboratories/standards , Pertussis Toxin/immunology , Pertussis Vaccine/immunology , Pertussis Vaccine/toxicity , Reference Standards , Vaccines, Acellular/immunology , Vaccines, Acellular/standards , Vaccines, Acellular/toxicity , World Health Organization
4.
Reprod Toxicol ; 81: 259-271, 2018 10.
Article in English | MEDLINE | ID: mdl-30205136

ABSTRACT

A systematic literature review was conducted to identify Hershberger bioassays for ∼3200 chemicals including those used to validate the OECD/US EPA guideline assay, US EPA's chemicals screened for endocrine activity, and the library of chemicals run in US EPA 's ToxCast in vitro assays. For 134 chemicals that met pre-defined criteria, experimental results were extracted into a database used to characterize uncertainty in results and evaluate the concordance of the Hershberger assay with other in vivo rodent studies that measure androgen-responsive endpoints. Of 25 chemicals tested in >1 Hershberger study, 28% had disagreements between studies (i.e. ≥1 positive and ≥1 negative study), and of the 65 chemicals tested in Hershberger studies and other in vivo studies with androgen-responsive endpoints, 43% indicated disagreements, though in some cases these may be explained by differences in study designs or physiology of the animal model. Ultimately, 49 chemicals were identified with reproducible androgen pathway responses confirmed in ≥2 in vivo rodent studies that could be considered reference chemicals useful for validating alternative methods.


Subject(s)
Androgen Antagonists/toxicity , Androgens/toxicity , Biological Assay , Animals , Humans
5.
Reprod Toxicol ; 81: 272-280, 2018 10.
Article in English | MEDLINE | ID: mdl-30205137

ABSTRACT

A set of 39 reference chemicals with reproducible androgen pathway effects in vivo, identified in the companion manuscript [1], were used to interrogate the performance of the ToxCast/Tox 21 androgen receptor (AR) model based on 11 high throughput assays. Cytotoxicity data and specificity confirmation assays were used to distinguish assay loss-of-function from true antagonistic signaling suppression. Overall agreement was 66% (19/29), with ten additional inconclusive chemicals. Most discrepancies were explained using in vitro to in vivo extrapolation to estimate equivalent administered doses. The AR model had 100% positive predictive value for the in vivo response, i.e. there were no false positives, and chemicals with conclusive AR model results (agonist or antagonist) were consistently positive in vivo. Considering the lack of reproducibility of the in vivo Hershberger assay, the in vitro AR model may better predict specific AR interaction and can rapidly and cost-effectively screen thousands of chemicals without using animals.


Subject(s)
Androgen Antagonists/toxicity , Androgens/toxicity , Biological Assay , Models, Biological , Receptors, Androgen/metabolism , Animals , Databases, Factual , Male , Rats , Reproducibility of Results
6.
Intern Med J ; 46(11): 1328-1332, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27813353

ABSTRACT

Neutropenia in adult patients is often attributed to intercurrent viral infections; however, there are limited data describing the frequency or natural history of this phenomenon. We examined all patients presenting to three large hospitals in the Metro South region of South East Queensland with laboratory-confirmed influenza A or B throughout the 2015 influenza season (January-October). Four hundred and thirty-six patients were studied and 15.3% of this cohort were neutropenic (absolute neutrophil count <2.0 × 109 /L) with no identifiable cause other than the influenza. Importantly, the majority of cases were mild, with absolute neutrophil count remaining >1.0 × 109 /L. The incidence of neutropenia was significantly higher in association with influenza B than influenza A (18.3% vs 10.3%). We conclude that mild, transient neutropenia is common among patients with influenza infection and advise that it should not cause alarm or invite specific investigation unless severe or prolonged.


Subject(s)
Influenza, Human/complications , Influenza, Human/epidemiology , Neutropenia/epidemiology , Adult , Aged , Aged, 80 and over , Female , Humans , Incidence , Influenza, Human/classification , Leukocyte Count , Male , Middle Aged , Queensland/epidemiology , Retrospective Studies
7.
Pharmeur Bio Sci Notes ; 2016: 151-170, 2016.
Article in English | MEDLINE | ID: mdl-28279256

ABSTRACT

The 'International Workshop on Alternatives to the Murine Histamine Sensitization Test for Acellular Pertussis Vaccines: In Search of Acceptable Alternatives to the Murine Histamine Sensitization Test (HIST): What is Possible and Practical?' was held on 4 and 5 March 2015 in London, United Kingdom. Participants discussed the results of the data generated from an international collaborative study (BSP114 Phase 2) sponsored by the European Directorate for the Quality of Medicines & Health Care (EDQM) to determine if a modified Chinese hamster ovary (CHO) cell-based clustering assay is a suitable alternative to replace HIST. Workshop participants agreed that protocol transferability demonstrated in the collaborative study indicates that a standardised CHO cell assay is adequate for measuring pure PTx in reference preparations. However, vaccine manufacturers would still need to demonstrate that the method is valid to detect or measure residual PTx in their specific adjuvanted products. The 2 modified CHO cell protocols included in the study (the Direct and the Indirect Methods) deserve further consideration as alternatives to HIST. Using the CHO cell assay, an in vitro alternative, for acellular pertussis (aP) vaccine batch release testing would reduce the number of animals used for aP vaccine safety testing. A strategic, stepwise adoption plan was proposed, in which the alternative test would be used for release purposes first, and then, once sufficient confidence in its suitable performance has been gained, its use would be extended to stability testing.


Subject(s)
Animal Testing Alternatives/standards , Chemistry, Pharmaceutical/standards , Histamine/analysis , Pertussis Toxin/analysis , Animal Testing Alternatives/methods , Animals , CHO Cells , Chemistry, Pharmaceutical/methods , Cricetinae , Cricetulus , Education , London , Mice , Pertussis Toxin/therapeutic use , Pertussis Vaccine/standards , Pertussis Vaccine/therapeutic use , Whooping Cough/prevention & control
8.
Analyst ; 140(13): 4350-64, 2015 Jul 07.
Article in English | MEDLINE | ID: mdl-25909342

ABSTRACT

Biosensors are being developed to provide rapid, quantitative, diagnostic information to clinicians in order to help guide patient treatment, without the need for centralised laboratory assays. The success of glucose monitoring is a key example of where technology innovation has met a clinical need at multiple levels ­ from the pathology laboratory all the way to the patient's home. However, few other biosensor devices are currently in routine use. Here we review the challenges and opportunities regarding the integration of biosensor techniques into body fluid sampling approaches, with emphasis on the point-of-care setting.


Subject(s)
Biosensing Techniques/methods , Biosensing Techniques/trends , Body Fluids/chemistry , Proteins/chemistry , Animals , Humans , Sweat/chemistry , Tears/chemistry
9.
Phys Rev Lett ; 109(1): 015001, 2012 Jul 06.
Article in English | MEDLINE | ID: mdl-23031109

ABSTRACT

This Letter describes the first experimental demonstration of the guiding of a relativistic electron beam in a solid target using two colinear, relativistically intense, picosecond laser pulses. The first pulse creates a magnetic field that guides the higher-current, fast-electron beam generated by the second pulse. The effects of intensity ratio, delay, total energy, and intrinsic prepulse are examined. Thermal and Kα imaging show reduced emission size, increased peak emission, and increased total emission at delays of 4-6 ps, an intensity ratio of 10∶1 (second:first) and a total energy of 186 J. In comparison to a single, high-contrast shot, the inferred fast-electron divergence is reduced by 2.7 times, while the fast-electron current density is increased by a factor of 1.8. The enhancements are reproduced with modeling and are shown to be due to the self-generation of magnetic fields. Such a scheme could be of considerable benefit to fast-ignition inertial fusion.

10.
Phys Rev Lett ; 106(22): 225003, 2011 Jun 03.
Article in English | MEDLINE | ID: mdl-21702607

ABSTRACT

By using a thick (250 µm) target with 350 µm radius of curvature, the intense proton beam driven by a petawatt laser is focused at a distance of ∼1 mm from the target for all detectable energies up to ∼25 MeV. The thickness of the foil facilitates beam focusing as it suppresses the dynamic evolution of the beam divergence caused by peaked electron flux distribution at the target rear side. In addition, reduction in inherent beam divergence due to the target thickness relaxes the curvature requirement for short-range focusing. Energy resolved mapping of the proton beam trajectories from mesh radiographs infers the focusing and the data agree with a simple geometrical modeling based on ballistic beam propagation.

11.
Bone Marrow Transplant ; 45(4): 662-7, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19684623

ABSTRACT

Patients on systemic glucocorticoids for GVHD after hematopoietic cell transplant are susceptible to invasive fungal infections (IFI), which greatly contribute to morbidity and mortality. We evaluated the efficacy of prophylactic treatment options (voriconazole or fluconazole vs itraconazole) for IFI by performing a retrospective review of patients on glucocorticoids for GVHD who were administered voriconazole (n=97), fluconazole (n=36) or itraconazole (n=36). IFI developed in 7/72 (10%) patients on fluconazole/itraconazole vs 2/97 (2%) on voriconazole (P=0.03) within the first 100 days of glucocorticoids. Five (7%) patients developed Aspergillus IFI on fluconazole/itraconazole, compared with none on voriconazole (0%) (P=0.008); Aspergillus IFI resulted in death in all five patients. We found that IFI occurred in patients who received an initial dose of at least 2 mg/kg/day of prednisone or equivalent; when the analysis was restricted to these patients, the hazard ratio (0.39; 95% confidence interval: 0.08-1.86) was consistent with a protective effect of voriconazole compared with fluconazole/itraconazole, although this subset analysis did not reach significance. OS at 100 days after start of glucocorticoids was 77% in patients administered fluconazole/itraconazole and 85% in those administered voriconazole (P=0.22). Our results suggest that voriconazole is more effective than fluconazole/itraconazole in preventing IFI, especially aspergillosis, in patients receiving glucocorticoids post transplant.


Subject(s)
Antifungal Agents/therapeutic use , Glucocorticoids/adverse effects , Graft vs Host Disease/drug therapy , Hematopoietic Stem Cell Transplantation , Mycoses/prevention & control , Pyrimidines/therapeutic use , Triazoles/therapeutic use , Adult , Chemoprevention , Female , Fluconazole/therapeutic use , Humans , Itraconazole/therapeutic use , Male , Middle Aged , Retrospective Studies , Voriconazole
12.
Phys Rev Lett ; 105(13): 135001, 2010 Sep 24.
Article in English | MEDLINE | ID: mdl-21230778

ABSTRACT

We demonstrate experimentally that the relativistic electron flow in a dense plasma can be efficiently confined and guided in targets exhibiting a high-resistivity-core-low-resistivity-cladding structure analogous to optical waveguides. The relativistic electron beam is shown to be confined to an area of the order of the core diameter (50 µm), which has the potential to substantially enhance the coupling efficiency of electrons to the compressed fusion fuel in the Fast Ignitor fusion in full-scale fusion experiments.

13.
Phys Rev Lett ; 105(19): 195008, 2010 Nov 05.
Article in English | MEDLINE | ID: mdl-21231179

ABSTRACT

The use of two separate ultraintense laser pulses in laser-proton acceleration was compared to the single pulse case employing the same total laser energy. A double pulse profile, with the temporal separation of the pulses varied between 0.75-2.5 ps, was shown to result in an increased maximum proton energy and an increase in conversion efficiency to fast protons by up to a factor of 3.3. Particle-in-cell simulations indicate the existence of a two stage acceleration process. The second phase, induced by the main pulse preferentially accelerates slower protons located deeper in the plasma, in contrast to conventional target normal sheath acceleration.

14.
Phys Rev Lett ; 102(22): 225002, 2009 Jun 05.
Article in English | MEDLINE | ID: mdl-19658870

ABSTRACT

Coherent wake emission is a unique source of extreme ultraviolet radiation and has been recently shown to provide the basis for intense attosecond light. Here we present a novel scheme, supported by particle-in-cell simulations, demonstrating that enhancement and spectral control of the coherent wake emission signal can be achieved by modifying the interaction plasma density ramp. Significant tunable enhancement of harmonic emission is verified experimentally, with factors of >50 in relative signal increase achieved in a narrow band of harmonics at the cutoff frequency.

15.
Phys Rev Lett ; 103(4): 045002, 2009 Jul 24.
Article in English | MEDLINE | ID: mdl-19659362

ABSTRACT

We report on the acceleration of ion beams from ultrathin diamondlike carbon foils of thickness 50, 30, and 10 nm irradiated by ultrahigh contrast laser pulses at intensities of approximately 7 x 10;{19} W/cm;{2}. An unprecedented maximum energy of 185 MeV (15 MeV/u) for fully ionized carbon atoms is observed at the optimum thickness of 30 nm. The enhanced acceleration is attributed to self-induced transparency, leading to strong volumetric heating of the classically overdense electron population in the bulk of the target. Our experimental results are supported by both particle-in-cell (PIC) simulations and an analytical model.

16.
Rev Sci Instrum ; 80(3): 033301, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19334914

ABSTRACT

This article reports on an experimental method to fully reconstruct laser-accelerated proton beam parameters called radiochromic film imaging spectroscopy (RIS). RIS allows for the characterization of proton beams concerning real and virtual source size, envelope- and microdivergence, normalized transverse emittance, phase space, and proton spectrum. This technique requires particular targets and a high resolution proton detector. Therefore thin gold foils with a microgrooved rear side were manufactured and characterized. Calibrated GafChromic radiochromic film (RCF) types MD-55, HS, and HD-810 in stack configuration were used as spatial and energy resolved film detectors. The principle of the RCF imaging spectroscopy was demonstrated at four different laser systems. This can be a method to characterize a laser system with respect to its proton-acceleration capability. In addition, an algorithm to calculate the spatial and energy resolved proton distribution has been developed and tested to get a better idea of laser-accelerated proton beams and their energy deposition with respect to further applications.

17.
Phys Rev Lett ; 102(5): 055001, 2009 Feb 06.
Article in English | MEDLINE | ID: mdl-19257515

ABSTRACT

Guided transport of a relativistic electron beam in solid is achieved experimentally by exploiting the strong magnetic fields created at the interface of two metals of different electrical resistivities. This is of substantial relevance to the Fast Ignitor approach to fusion energy production [M. Tabak, Phys. Plasmas 12, 057305 (2005)10.1063/1.1871246], since it allows the electron deposition to be spatially tailored-thus adding substantial design flexibility and preventing inefficiencies due to electron beam spreading. In the experiment, optical transition radiation and thermal emission from the target rear surface provide a clear signature of the electron confinement within a high resistivity tin layer sandwiched transversely between two low resistivity aluminum slabs. The experimental data are found to agree well with numerical simulations.

18.
Tissue Antigens ; 72(6): 507-16, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19000150

ABSTRACT

Allogeneic hematopoietic stem cell transplantation (SCT) remains the only available curative therapy for hematological malignancy. It does, however, result in significant morbidity and mortality, predominantly as a consequence of infections, leukemic relapse and graft-vs-host disease (GVHD). While differences in human leukocyte antigen (HLA) molecules between donor and host make a crucial contribution to the alloreactivity driving the donor-antihost response, the cytokine milieu consisting of molecules that both promote and regulate the alloresponse after transplantation is also critical. As such, genetic studies correlating donor and/or host cytokine polymorphisms with disease outcomes have provided useful insight into disease pathogenesis, often confirming effects that have been dissected in animal models of the disease. It is now clear that the polymorphic expression of key cytokines (particularly tumor necrosis factor and interleukin 10) has a demonstrable effect on disease outcome and overall transplant-related mortality. Consideration of the role of genetic polymorphisms in GVHD severity and procedural mortality associated with SCT will lead to improvements in patient outcome such that the addition of non-HLA genetic typing of potential donors will allow optimization of donor selection for a given recipient. This review provides a discussion of the current state of the literature regarding polymorphic expression of the key GVHD cytokines and their capacity to predict clinical disease outcome.


Subject(s)
Cytokines/genetics , Graft vs Host Disease/genetics , Hematopoietic Stem Cell Transplantation/adverse effects , Polymorphism, Genetic , Animals , Genotype , Graft vs Host Disease/immunology , Humans , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
19.
Phys Rev Lett ; 100(10): 105004, 2008 Mar 14.
Article in English | MEDLINE | ID: mdl-18352198

ABSTRACT

The emission characteristics of intense laser driven protons are controlled using ultrastrong (of the order of 10(9) V/m) electrostatic fields varying on a few ps time scale. The field structures are achieved by exploiting the high potential of the target (reaching multi-MV during the laser interaction). Suitably shaped targets result in a reduction in the proton beam divergence, and hence an increase in proton flux while preserving the high beam quality. The peak focusing power and its temporal variation are shown to depend on the target characteristics, allowing for the collimation of the inherently highly divergent beam and the design of achromatic electrostatic lenses.

20.
Phys Rev Lett ; 100(1): 015003, 2008 Jan 11.
Article in English | MEDLINE | ID: mdl-18232779

ABSTRACT

Metal foil targets were irradiated with 1 mum wavelength (lambda) laser pulses of 5 ps duration and focused intensities (I) of up to 4x10;{19} W cm;{-2}, giving values of both Ilambda;{2} and pulse duration comparable to those required for fast ignition inertial fusion. The divergence of the electrons accelerated into the target was determined from spatially resolved measurements of x-ray K_{alpha} emission and from transverse probing of the plasma formed on the back of the foils. Comparison of the divergence with other published data shows that it increases with Ilambda;{2} and is independent of pulse duration. Two-dimensional particle-in-cell simulations reproduce these results, indicating that it is a fundamental property of the laser-plasma interaction.

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