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1.
Transfus Med Hemother ; 47(4): 279-286, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32884500

RESUMO

BACKGROUND: MNS blood group system genes GYPA and GYPB share a high degree of sequence homology and gene structure. Homologous exchanges between GYPA and GYPB form hybrid genes encoding hybrid glycophorins GP(A-B-A) and GP(B-A-B). Over 20 hybrid glycophorins have been characterised. Each has a distinct phenotype defined by the profile of antigens expressed including Mia. Seven hybrid glycophorins carry Mia and have been reported in Caucasian and Asian population groups. In Australia, the population is diverse; however, the prevalence of hybrid glycophorins in the population has never been determined. The aims of this study were to determine the frequency of Mia and to classify Mia-positive hybrid glycophorins in an Australian blood donor population. METHOD: Blood samples from 5,098 Australian blood donors were randomly selected and screened for Mia using anti-Mia monoclonal antibody (CBC-172) by standard haemagglutination technique. Mia-positive red blood cells (RBCs) were further characterised using a panel of phenotyping reagents. Genotyping by high-resolution melting analysis and DNA sequencing were used to confirm serology. RESULT: RBCs from 11/5,098 samples were Mia-positive, representing a frequency of 0.22%. Serological and molecular typing identified four types of Mia-positive hybrid glycophorins: GP.Hut (n = 2), GP.Vw (n = 3), GP.Mur (n = 5), and 1 GP.Bun (n = 1). GP.Mur was the most common. CONCLUSION: This is the first comprehensive study on the frequency of Mia and types of hybrid glycophorins present in an Australian blood donor population. The demographics of Australia are diverse and ever-changing. Knowing the blood group profile in a population is essential to manage transfusion needs.

2.
Transfus Med Rev ; 33(2): 111-117, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31023581

RESUMO

Erythroid-specific Krüppel-like factor 1, or KLF1, is an integral transcriptional activator for erythropoiesis. Genetic variants within KLF1 can result in a range of erythropoietic clinical phenotypes from benign to significant. The In(Lu) phenotype refers to changes in the quantitative expression of blood group-associated red cell surface molecules due to KLF1 variants which are otherwise clinically benign. These clinically benign KLF1 variants are associated with a reduced expression of 1 or more red cell membrane proteins/carbohydrates that carry blood group antigens for the LU (Lutheran), IN (Indian), P1PK, LW (Landsteiner-Wiener), KN (Knops), OK, RAPH, and I blood group systems. This is of significance during routine serologic blood typing when expression falls below the test sensitivity and therefore impacts on the ability to accurately detect the presence of affected blood group antigens. This is of clinical importance because the transfusion requirements for individuals with the In(Lu) phenotype differ from those of individuals that have a true Lunull phenotype. With this review, we summarize the current body of knowledge with regard to the In(Lu) phenotype and associated KLF1 variants. Our review also highlights discordant reports and provides insights for future research and management strategies. Serological heterogeneity in blood group expression of In(Lu) individuals has been shown, but studies are limited by the low prevalence of the phenotype and therefore the small numbers of samples. They are further limited by availability and inconsistent application of serological reagents and varying test algorithms. With the advent of genome sequence-based testing, an increasing list of In(Lu)-associated KLF1 variants is being revealed. The spectrum of effects on blood group expression due to these variants warrants further attention, and a consistent methodological approach of studies in larger cohorts is required. We propose that a recently reported testing framework of standardized serological studies, flow cytometry, and variant analysis be adopted; and that the international databases be curated to document KLF1 variability and the resultant In(Lu) red cell blood group expression. This will provide better classification of KLF1 variants affecting blood group expression and allow for phenotype prediction from genotype, accurate typing of In(Lu) individuals, and better transfusion management of related challenging transfusion scenarios.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Fatores de Transcrição Kruppel-Like/genética , Sistema do Grupo Sanguíneo Lutheran/genética , Polimorfismo Genético , Transfusão de Sangue , Genótipo , Humanos , Mutação , Fenótipo , Análise de Sequência de DNA
3.
Transfusion ; 58(10): 2414-2420, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30222867

RESUMO

INTRODUCTION: KLF1 is an essential transcriptional activator that drives erythropoiesis. KLF1 variants can result in the Inhibitor of Lutheran, or In(Lu), phenotype where red blood cells (RBCs) have reduced BCAM (LU) and CD44 (IN). Other RBC surface molecules also have changed expression; however, there is controversy in the literature regarding which are truly impacted. We aimed to investigate KLF1 variants in the Australian population. STUDY DESIGN AND METHODS: In(Lu) samples were sourced through screening and through the RBC reference laboratory. Blood donor samples (8036) were screened to identify weakened/absent Lub antigen. Samples were genotyped by massively parallel sequencing, while surface carbohydrates and blood group molecules were assessed by flow cytometry. Hemoglobin (Hb) types were analyzed by high-performance liquid chromatography. RESULTS: Four of 8036 donors were identified to be In(Lu), and two previously identified In(Lu) samples were provided from the RBC reference laboratory. Five different KLF1 variants were identified; two were novel: c.954G>C/p.Trp318Cys and c.421C>T/p.Arg141*. BCAM and CD44 were reduced in all samples, consistent with previous reports. As a group, In(Lu) RBCs had reduced CD35 (KN), ICAM4 (LW), and CD147 (OK), and demonstrated increased binding of lectins ECA and SNAI. One In(Lu) sample had elevated HbF and another elevated HbA2. CONCLUSION: Different KLF1 variants may potentially produce variable phenotypes. A framework for investigating KLF1 variants and their phenotypic impact has been provided. In the future, given available international databases, further testing algorithms (as advocated here) will allow for correlation of phenotype with genotype and therefore accurately document this variability between KLF1 variants.


Assuntos
Antígenos de Grupos Sanguíneos/sangue , Eritrócitos/imunologia , Variação Genética , Fatores de Transcrição Kruppel-Like/genética , Sistema do Grupo Sanguíneo Lutheran/química , Austrália , Cromatografia Líquida de Alta Pressão , Citometria de Fluxo , Estudos de Associação Genética , Humanos , Fenótipo
4.
Lancet HIV ; 5(4): e190-e198, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29540265

RESUMO

BACKGROUND: To move towards ending AIDS by 2030, HIV resources should be allocated cost-effectively. We used the Optima HIV model to estimate how global HIV resources could be retargeted for greatest epidemiological effect and how many additional new infections could be averted by 2030. METHODS: We collated standard data used in country modelling exercises (including demographic, epidemiological, behavioural, programmatic, and expenditure data) from Jan 1, 2000, to Dec 31, 2015 for 44 countries, capturing 80% of people living with HIV worldwide. These data were used to parameterise separate subnational and national models within the Optima HIV framework. To estimate optimal resource allocation at subnational, national, regional, and global levels, we used an adaptive stochastic descent optimisation algorithm in combination with the epidemic models and cost functions for each programme in each country. Optimal allocation analyses were done with international HIV funds remaining the same to each country and by redistributing these funds between countries. FINDINGS: Without additional funding, if countries were to optimally allocate their HIV resources from 2016 to 2030, we estimate that an additional 7·4 million (uncertainty range 3·9 million-14·0 million) new infections could be averted, representing a 26% (uncertainty range 13-50%) incidence reduction. Redistribution of international funds between countries could avert a further 1·9 million infections, which represents a 33% (uncertainty range 20-58%) incidence reduction overall. To reduce HIV incidence by 90% relative to 2010, we estimate that more than a three-fold increase of current annual funds will be necessary until 2030. The most common priorities for optimal resource reallocation are to scale up treatment and prevention programmes targeting key populations at greatest risk in each setting. Prioritisation of other HIV programmes depends on the epidemiology and cost-effectiveness of service delivery in each setting as well as resource availability. INTERPRETATION: Further reductions in global HIV incidence are possible through improved targeting of international and national HIV resources. FUNDING: World Bank and Australian NHMRC.


Assuntos
Síndrome da Imunodeficiência Adquirida/economia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Algoritmos , Análise Custo-Benefício , Alocação de Recursos para a Atenção à Saúde , Humanos , Modelos Teóricos , Profilaxia Pré-Exposição , Alocação de Recursos , Fatores de Risco
5.
J Int AIDS Soc ; 19(1): 20627, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26928810

RESUMO

INTRODUCTION: International investment in the response to HIV and AIDS has plateaued and its future level is uncertain. With many countries committed to ending the epidemic, it is essential to allocate available resources efficiently over different response periods to maximize impact. The objective of this study is to propose a technique to determine the optimal allocation of funds over time across a set of HIV programmes to achieve desirable health outcomes. METHODS: We developed a technique to determine the optimal time-varying allocation of funds (1) when the future annual HIV budget is pre-defined and (2) when the total budget over a period is pre-defined, but the year-on-year budget is to be optimally determined. We use this methodology with Optima, an HIV transmission model that uses non-linear relationships between programme spending and associated programmatic outcomes to quantify the expected epidemiological impact of spending. We apply these methods to data collected from Zambia to determine the optimal distribution of resources to fund the right programmes, for the right people, at the right time. RESULTS AND DISCUSSION: Considering realistic implementation and ethical constraints, we estimate that the optimal time-varying redistribution of the 2014 Zambian HIV budget between 2015 and 2025 will lead to a 7.6% (7.3% to 7.8%) decrease in cumulative new HIV infections compared with a baseline scenario where programme allocations remain at 2014 levels. This compares to a 5.1% (4.6% to 5.6%) reduction in new infections using an optimal allocation with constant programme spending that recommends unrealistic programmatic changes. Contrasting priorities for programme funding arise when assessing outcomes for a five-year funding period over 5-, 10- and 20-year time horizons. CONCLUSIONS: Countries increasingly face the need to do more with the resources available. The methodology presented here can aid decision-makers in planning as to when to expand or contract programmes and to which coverage levels to maximize impact.


Assuntos
Infecções por HIV/economia , Alocação de Recursos , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Modelos Teóricos , Zâmbia
6.
J Acquir Immune Defic Syndr ; 68 Suppl 2: S213-20, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25723987

RESUMO

BACKGROUND: Niger's low-burden, sex-work-driven HIV epidemic is situated in a context of high economic and demographic growth. Resource availability of HIV/AIDS has been decreasing recently. In 2007-2012, only 1% of HIV expenditure was for sex work interventions, but an estimated 37% of HIV incidence was directly linked to sex work in 2012. The Government of Niger requested assistance to determine an efficient allocation of its HIV resources and to strengthen HIV programming for sex workers. METHODS: Optima, an integrated epidemiologic and optimization tool, was applied using local HIV epidemic, demographic, programmatic, expenditure, and cost data. A mathematical optimization algorithm was used to determine the best resource allocation for minimizing HIV incidence and disability-adjusted life years (DALYs) over 10 years. RESULTS: Efficient allocation of the available HIV resources, to minimize incidence and DALYs, would increase expenditure for sex work interventions from 1% to 4%-5%, almost double expenditure for antiretroviral treatment and for the prevention of mother-to-child transmission, and reduce expenditure for HIV programs focusing on the general population. Such an investment could prevent an additional 12% of new infections despite a budget of less than half of the 2012 reference year. Most averted infections would arise from increased funding for sex work interventions. CONCLUSIONS: This allocative efficiency analysis makes the case for increased investment in sex work interventions to minimize future HIV incidence and DALYs. Optimal HIV resource allocation combined with improved program implementation could have even greater HIV impact. Technical assistance is being provided to make the money invested in sex work programs work better and help Niger to achieve a cost-effective and sustainable HIV response.


Assuntos
Infecções por HIV/prevenção & controle , Custos de Cuidados de Saúde , Profissionais do Sexo , Adolescente , Adulto , Criança , Pré-Escolar , Análise Custo-Benefício , Epidemias , Feminino , Infecções por HIV/economia , Infecções por HIV/epidemiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Níger/epidemiologia , Prevalência , Alocação de Recursos , Adulto Jovem
7.
Clin Infect Dis ; 59 Suppl 1: S28-31, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24926029

RESUMO

Treatment as prevention (TasP) has been added to the toolbox of human immunodeficiency virus (HIV) prevention technologies, and countries are at different stages of TasP deployment. In this article we review some of the cost implications and summarize effectiveness data from different settings. Also, we reflect on the affordability and feasibility of programmatic deployment as well as the multiple challenges of maintaining service quality while HIV treatment programs grow in size and complexity. We conclude that in low-resource settings, TasP progress will be very incremental with progressively earlier treatment initiation while working within the capacity and resource constraints of the respective healthcare systems. In the long-term, feasibility will rely on complementary interventions to reduce new HIV infections, such as male circumcision, and on demand creation for early treatment uptake as well as adherence. TasP holds potential for moving us closer to the global goal of ending AIDS.


Assuntos
Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Análise Custo-Benefício , Infecções por HIV/economia , Humanos
8.
J Child Health Care ; 11(2): 98-111, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17494985

RESUMO

This article explores the impact of diagnostic/psychiatric labelling on the attitudes and behavioural intentions of school-aged children towards a hypothetical peer presented with symptoms of attention deficit hyperactivity disorder (ADHD). A sample of 120 children aged 11-12 years read one of three vignettes describing the behaviour of a gender-neutral, same-age peer presenting with symptoms of ADHD. The participants completed self-report measures of attitudes and behavioural intentions after reading the respective vignettes. The majority of participants perceived the vignette character as being male and the attitude held towards him was predominately negative. Significant positive relationships were found between attitudes and children's willingness to engage in social, academic and physical activities. Diagnostic/psychiatric labelling had no additional influence upon attitudes or behavioural intentions. Children's negative attitude towards peers with symptoms of ADHD, given its association with friendship choice, is an important target for change in reducing stigma.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Atitude , Relações Interpessoais , Grupo Associado , Análise de Variância , Criança , Inglaterra , Feminino , Humanos , Intenção , Masculino , Preconceito , Estereotipagem
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