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1.
Vox Sang ; 119(5): 409-416, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38373848

RESUMEN

BACKGROUND AND OBJECTIVES: Two-Spirit, trans, nonbinary and other gender-diverse (2STGD) donors face challenges in donation. While many blood operators aim to address these challenges, to date, no empirical study with these donors has been conducted to guide their efforts. This paper reports 2STGD donors' views on a two-step approach asking donors their gender and sex assigned at birth (SAAB), and expanding gender options in donor registration. MATERIALS AND METHODS: A qualitative community-based study was conducted with 2STGD donors (n = 85) in Canada. Semi-structured, in-depth interviews were conducted from July to October 2022, audio-recorded and transcribed. Data were analysed using a thematic analytic framework. RESULTS: Participants were divided on their views of a two-step approach asking gender and SAAB. Themes underlying views in favour of this approach included the following: demonstrating validation and visibility, and treating 2STGD donors and cisgender donors alike. Themes underlying views not in favour or uncertain included potential for harm, compromising physical safety, and invalidation. All participants were in favour of expanding gender options if blood operators must know donors' gender. CONCLUSION: Results indicate that a two-step approach for all donors is not recommended unless the blood operator must know both a donor's gender and SAAB to ensure donor and/or recipient safety. Gender options should be expanded beyond binary options. Ongoing research and evidence synthesis are needed to determine how best to apply donor safety measures to nonbinary donors.


Asunto(s)
Donantes de Sangre , Humanos , Femenino , Masculino , Adulto , Canadá , Persona de Mediana Edad , Minorías Sexuales y de Género , Adulto Joven , Investigación Cualitativa
2.
J Hazard Mater ; 463: 132832, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-37951165

RESUMEN

Computational fluid dynamics simulations are used to model the velocity field and the transport of a passive scalar within a micro-scale chamber used to measure diffusional transport through various building materials. Comparisons of solutions obtained using a steady, laminar flow assumption with velocity measurements obtained from hot-wire anemometry show that the numerical method generally underpredicts the near surface velocity field. The results improve for higher flow rates and for carpeted test materials, modeled as a porous resistive layer. Calculations involving scalar transport within the upper chamber of the sampling device are performed for different flow rates and Schmidt numbers. The results are used to develop a model for the convective mass transfer coefficient, correlated as a function of the Reynolds and Schmidt numbers as well as the porosity of the carpet. This model is integrated into a steady-state mass transport model for predicting the diffusion of gaseous formaldehyde through various test materials. Predictions of diffusion and partition coefficients for vinyl flooring, gypsum wall board, and carpet are within the ranges of literature data. The results indicate that a perfectly mixed upper part of the sampling device is an adequate assumption.

3.
Clin Transl Immunology ; 12(9): e1466, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37692904

RESUMEN

Objectives: Despite the success of immune checkpoint blockade, most metastatic melanoma patients fail to respond to therapy or experience severe toxicity. Assessment of biomarkers and immunophenotypes before or early into treatment will help to understand favourable responses and improve therapeutic outcomes. Methods: We present a high-dimensional approach for blood T-cell profiling using three multi-parameter cytometry panels: (1) a TruCount panel for absolute cell counts, (2) a 27-colour spectral panel assessing T-cell markers and (3) a 20-colour spectral panel evaluating intracellular cytokine expression. Pre-treatment blood mononuclear cells from patients and healthy controls were cryopreserved before staining across 11 batches. Batch effects were tracked using a single-donor control and the suitability of normalisation was assessed. The data were analysed using manual gating and high-dimensional strategies. Results: Batch-to-batch variation was minimal, as demonstrated by the dimensionality reduction of batch-control samples, and normalisation did not improve manual or high-dimensional analysis. Application of the workflow demonstrated the capacity of the panels and showed that patients had fewer lymphocytes than controls (P = 0.0027), due to lower naive CD4+ (P = 0.015) and CD8+ (P = 0.011) T cells and follicular helper T cells (P = 0.00076). Patients showed trends for higher proportions of Ki67 and IL-2-expressing cells within CD4+ and CD8+ memory subsets, and increased CD57 and EOMES expression within TCRγδ+ T cells. Conclusion: Our optimised high-parameter spectral cytometry approach provided in-depth profiling of blood T cells and found differences in patient immunophenotype at baseline. The robustness of our workflow, as demonstrated by minimal batch effects, makes this approach highly suitable for the longitudinal evaluation of immunotherapy effects.

4.
Animals (Basel) ; 13(9)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37174537

RESUMEN

Monitoring livestock allows insights to graziers on valuable information such as spatial distribution, foraging patterns, and animal behavior, which can significantly improve the management of livestock for optimal production. This study aimed to understand what potential variables are significant for predicting where sheep spent the most time in native (NP) and improved (IP) paddocks. Wethers (castrated male sheep) were tracked using Global Positioning System (GPS) collars on 15 sheep in the IP and 15 in the NP, respectively, on a property located in the Monaro region of Southern New South Wales, Australia. Trials were performed over four six-day periods in April, July, and November of 2014 and March in 2015. Data were analyzed to understand various trends that may have occurred during different seasons, using random forest models (RFMs). Of the factors investigated, Normalized Difference Vegetation Index (NDVI) was significant (p < 0.01) and highly important for wethers in the IP, but not the NP, suggesting that quality of pasture was key for wethers in the IP. Elevation, temperature, and near distance to trees were important and significant for predicting residency of wethers in the IP, as well as the NP. The result of this study highlights the ability of predictive models to provide insights on behavior-based modelling of GPS data and further enhance current knowledge about location-based choices of sheep on paddocks.

5.
BMC Public Health ; 23(1): 694, 2023 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-37060069

RESUMEN

INTRODUCTION: The COVID-19 pandemic has increased online interactions and the spread of misinformation. Some researchers anticipate benefits stemming from improved public awareness of the value of vaccines while others worry concerns around vaccine development and public health mandates may have damaged public trust. There is a need to understand whether the COVID-19 pandemic, vaccine development, and vaccine mandates have influenced HPV vaccine attitudes and sentiments to inform health communication strategies. METHODS: We collected 596,987 global English-language tweets from January 2019-May 2021 using Twitter's Academic Research Product track. We determined vaccine confident and hesitant networks discussing HPV immunization using social network analysis. Then, we used a neural network approach to natural language processing to measure narratives and sentiment pertaining to HPV immunization. RESULTS: Most of the tweets in the vaccine hesitant network were negative in tone (54.9%) and focused on safety concerns surrounding the HPV vaccine while most of the tweets in the vaccine confident network were neutral (51.6%) and emphasized the health benefits of vaccination. Growth in negative sentiment among the vaccine hesitant network corresponded with legislative efforts in the State of New York to mandate HPV vaccination for public school students in 2019 and the WHO declaration of COVID-19 as a Global Health Emergency in 2020. In the vaccine confident network, the number of tweets concerning the HPV vaccine decreased during the COVID-19 pandemic but in both vaccine hesitant and confident networks, the sentiments, and themes of tweets about HPV vaccine were unchanged. CONCLUSIONS: Although we did not observe a difference in narratives or sentiments surrounding the HPV vaccine during the COVID-19 pandemic, we observed a decreased focus on the HPV vaccine among vaccine confident groups. As routine vaccine catch-up programs restart, there is a need to invest in health communication online to raise awareness about the benefits and safety of the HPV vaccine.


Asunto(s)
COVID-19 , Comunicación en Salud , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Medios de Comunicación Sociales , Humanos , COVID-19/prevención & control , Análisis de Sentimientos , Infecciones por Papillomavirus/prevención & control , Pandemias/prevención & control , Red Social
6.
Radiother Oncol ; 173: 299-305, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35772575

RESUMEN

BACKGROUND: The addition of stereotactic ablative radiotherapy (SABR) to immune checkpoint inhibitors (ICIs) has the potential to significantly improve outcomes in the treatment of metastatic melanoma. We analysed peripheral blood immune cells of patients receiving combination SABR and ICI to detect the effect of treatment and identify potential biomarkers that predict outcome. METHODS: 24 polymetastatic melanoma patients participated in the SABR IMPACT trial, receiving standard dose immunotherapy with anti-PD-1 and/or anti-CTLA-4 and stereotactic ablative radiotherapy to one site. Comprehensive immunophenotyping of T-cells was performed with flow cytometry on blood samples from 13 patients at baseline and following the first 4 cycles of treatment. RESULTS: Following four cycles of immunotherapy and SABR, the proportion of naïve subsets were reduced within both the CD4 and CD8 T-cell lineages. Independently, SABR resulted in increased expression of PD-1 (p = 0.019) and ICOS (p = 0.046) on the CD8+ T-cells, accompanied by a reduction in regulatory T-cell frequencies (p = 0.048). A multivariate discriminant analysis revealed a baseline signature of lower levels of CD8+ naive T-cells and higher expression of TIM-3 on regulatory T-cells and memory T-cells better predicted response. CONCLUSION: The combination of immunotherapy and SABR changed the immunophenotype of blood T cells, with some shifts attributable to SABR. Importantly, we identified a T-cell signature at baseline that best predicted response. Validation of these findings in an independent cohort could confirm these as biomarkers at baseline or early during treatment, and whether these can be utilised to stratify patients for high or low intensity treatment to reduce toxicity.


Asunto(s)
Melanoma , Radiocirugia , Biomarcadores , Linfocitos T CD8-positivos , Humanos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Melanoma/tratamiento farmacológico , Radiocirugia/métodos
7.
Cell Rep Med ; 3(5): 100635, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35584627

RESUMEN

Human immunodeficiency virus type 1 (HIV-1) vaccination of cows has elicited broadly neutralizing antibodies (bNAbs). In this study, monoclonal antibodies (mAbs) are isolated from a clade A (KNH1144 and BG505) vaccinated cow using a heterologous clade B antigen (AD8). CD4 binding site (CD4bs) bNAb (MEL-1872) is more potent than a majority of CD4bs bNAbs isolated so far. MEL-1872 mAb with CDRH3 of 57 amino acids shows more potency (geometric mean half-maximal inhibitory concentration [IC50]: 0.009 µg/mL; breadth: 66%) than VRC01 against clade B viruses (29-fold) and than CHO1-31 against tested clade A viruses (21-fold). It also shows more breadth and potency than NC-Cow1, the only other reported anti-HIV-1 bovine bNAb, which has 60% breadth with geometric mean IC50 of 0.090 µg/mL in this study. Using successive different stable-structured SOSIP trimers in bovines can elicit bNAbs focusing on epitopes ubiquitous across subtypes. Furthermore, the cross-clade selection strategy also results in ultra-potent bNAbs.


Asunto(s)
Infecciones por VIH , VIH-1 , Vacunas , Animales , Anticuerpos Monoclonales , Anticuerpos Neutralizantes/química , Sitios de Unión , Anticuerpos ampliamente neutralizantes , Antígenos CD4 , Bovinos , Femenino , Anticuerpos Anti-VIH , Infecciones por VIH/prevención & control , Productos del Gen env del Virus de la Inmunodeficiencia Humana
8.
J Virol ; 95(13): e0021921, 2021 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-33853957

RESUMEN

No prophylactic vaccine has provided robust protection against human immunodeficiency virus type 1 (HIV-1). Vaccine-induced broadly neutralizing antibodies (bNAbs) have not been achieved in humans and most animals; however, cows vaccinated with HIV-1 envelope trimers produce bNAbs with unusually long third heavy complementarity-determining regions (CDRH3s). Alongside neutralization, Fc-mediated effector functions, including antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis (ADP), may be critical for in vivo bNAb antiviral activity. Here, we aimed to augment the Fc-dependent effector functions of a chimeric human-bovine bNAb, NC-Cow1, which binds the CD4 binding site (CD4bs) and exhibits broader and more potent neutralization than most human CD4bs bNAbs by using an exceptionally long 60-amino acid (aa) CDRH3. The bovine variable region of NC-Cow1 was paired with a human IgG1 Fc region mutated to create the following three variants: G236R/L328R (GRLR) that abrogates Fc-gamma receptor (FcγR) binding, and two variants that enhance binding, namely, G236A/S239D/I332E (GASDIE) and G236A/S239D/A330L/I332E (GASDALIE). Both GASDIE and GASDALIE improved binding to human FcγRIIA and FcγRIIIA, enhanced human natural killer (NK) cell activation, and mediated higher levels of ADCC and ADP activity than the wild-type human IgG1 Fc. GASDALIE mediated higher phagocytic activity than GASDIE. As expected, GRLR eliminated binding to FcγRs and did not mediate ADCC or ADP. We demonstrated that mutations in the human Fc region of bovine chimeric antibodies with ultralong CDRH3s could enhance antibody effector functions while maintaining envelope binding and neutralization. This study will have significant implications in the development of multifunctional anti-HIV antibodies, which may be important to prevent HIV-1 transmission in an antibody-based topical microbicide. IMPORTANCE Despite successful antiviral chemotherapy, human immunodeficiency virus (HIV) is still a lifelong persistent virus, and no vaccine yet prevents HIV transmission. Topical microbicides offer an important alternative method to prevent sexual transmission of HIV-1. With the production of highly potent anti-HIV-1 broadly neutralizing antibodies (bNAbs) and multifunctional antibodies, monoclonal antibodies are now important prophylactic agents. Recently discovered anti-HIV-1 bovine bNAbs (with higher potency and breadth than most human bNAbs) could be novel candidates as potent topical microbicides. Our study is significant as it demonstrates the compatibility of combining bovine-derived neutralization with human-derived antibody-effector functions. This study is a new approach to antibody engineering that strengthens the feasibility of using high-potency bovine variable region bNAbs with augmented Fc function and promotes them as a strong candidate for antibody-mediated therapies.


Asunto(s)
Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Anticuerpos ampliamente neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/prevención & control , Proteínas Recombinantes de Fusión/inmunología , Animales , Bovinos , Línea Celular , Infecciones por VIH/transmisión , VIH-1/inmunología , Humanos , Inmunoglobulina G/inmunología , Células Asesinas Naturales/inmunología , Fagocitosis/inmunología , Ingeniería de Proteínas , Receptores de IgG/inmunología
9.
iScience ; 24(1): 101901, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33364589

RESUMEN

Cancers are the result of eco-evolutionary processes fueled by heritable phenotypic diversification and driven by environmentally dependent selection. Space represents a key growth-limiting ecological resource, the ability to explore this resource is likely under strong selection. Using agent-based modeling, we explored the interplay between phenotypic strategies centered on gaining access to new space through cell-extrinsic degradation of extracellular matrix barriers and the exploitation of this resource through maximizing cell proliferation. While cell proliferation is a cell-intrinsic property, newly accessed space represents a public good, which can benefit both producers and non-producers. We found that this interplay results in ecological succession, enabling emergence of large, heterogeneous, and highly proliferative populations. Even though in our simulations both remodeling and proliferation strategies were under strong positive selection, their interplay led to sub-clonal architecture that could be interpreted as evidence for neutral evolution, warranting cautious interpretation of inferences from sequencing of cancer genomes.

10.
J Propuls Power ; 34(2): 438-448, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33510552

RESUMEN

Hypersonic air-breathing engines rely on scramjet combustion processes, which involve high-speed, compressible, and highly turbulent reacting flows. The combustion environment and the turbulent flames at the heart of these engines are difficult to simulate and study in the laboratory under well controlled conditions. Typically, wind-tunnel testing is performed that more closely approximates engine development rather than a careful investigation of the underlying physics that drives the combustion process. The experiments described in this paper, along with companion data sets, aim to isolate the chemical kinetic effects and turbulence-chemistry interaction from the fuel-air mixing process in a dual-mode scramjet combustion environment. A unique fuel injection approach is adopted that produces a uniform fuel-air mixture at the entrance to the combustor and results in premixed combustion. This approach relies on the mixing enhancement of a precombustion shock train upstream of the dual-mode scramjet's combustor. For the first time a stable flame, anchored on a cavity flameholder, is reported for a scramjet combustor operating in premixed fuel-air mode. The new experimental capability has enabled numerous companion studies involving advanced diagnostics such as coherent anti-Stokes Raman scattering (CARS), particle image velocimetry (PIV), and planar laser induced fluorescence (PLIF).

11.
Int J Mass Spectrom ; 300(2-3): 99-107, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21499524

RESUMEN

Through a multi-disciplinary approach, the air amplifier is being evolved as a highly engineered device to improve detection limits of biomolecules when using electrospray ionization. Several key aspects have driven the modifications to the device through experimentation and simulations. We have developed a computer simulation that accurately portrays actual conditions and the results from these simulations are corroborated by the experimental data. These computer simulations can be used to predict outcomes from future designs resulting in a design process that is efficient in terms of financial cost and time. We have fabricated a new device with annular gap control over a range of 50 to 70 µm using piezoelectric actuators. This has enabled us to obtain better aerodynamic performance when compared to the previous design (2× more vacuum) and also more reproducible results. This is allowing us to study a broader experimental space than the previous design which is critical in guiding future directions. This work also presents and explains the principles behind a fractional factorial design of experiments methodology for testing a large number of experimental parameters in an orderly and efficient manner to understand and optimize the critical parameters that lead to obtain improved detection limits while minimizing the number of experiments performed. Preliminary results showed that several folds of improvements could be obtained for certain condition of operations (up to 34 folds).

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