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1.
J Clin Virol ; 64: 16-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25728073

RESUMO

Eastern Austria is neighbouring regions with ongoing West Nile virus (WNV) transmissions. Three human WNV infections had been diagnosed during the past decade in Austria. The Austrian Red Cross Blood Service (ARC-BS) started a first voluntary screening for WNV in blood donors from Eastern Austria by Nucleic Acid Testing (NAT) in June 2014. This is also the most extensive WNV surveillance programme in humans in Austria so far. In August 2014, one autochthonous WNV infection was detected in a blood donor from Vienna. By now, one in 67,800 whole blood donations was found to be positive for WNV RNA.


Assuntos
Doadores de Sangue , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Adulto , Áustria/epidemiologia , Feminino , Genoma Viral , Humanos , Programas de Rastreamento , Técnicas de Amplificação de Ácido Nucleico , Filogenia , RNA Viral/sangue , Febre do Nilo Ocidental/epidemiologia
2.
Vox Sang ; 108(3): 287-93, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25556963

RESUMO

BACKGROUND AND OBJECTIVES: Granulocyte-reactive antibodies can cause autoimmune and neonatal immune neutropenias as well as transfusion-related acute lung injury. The classical antibody-detection methods granulocyte aggregation test (GAT), granulocyte immunofluorescence test (GIFT) and monoclonal antibody-specific immobilization of granulocyte antigens (MAIGA) are time-consuming and technically challenging. In recent years, flow cytometric white blood cell immunofluorescence test (Flow-WIFT) and the microbeads assay LabScreen® Multi have emerged and are still subject of evaluation. These serological tests were compared on a screening and specification level. MATERIALS AND METHODS: For screening, the combination of GAT/GIFT was compared to Flow-WIFT testing 333 samples. Positive samples were further analysed with MAIGA and LabScreen® Multi. RESULTS: Granulocyte aggregation test/GIFT detected 77 positive samples, Flow-WIFT found 108 granulocyte-reactive samples. Six Samples were only positive in GAT/GIFT, and 37 samples were only positive in Flow-WIFT (κ = 0.682). Antibody specification with MAIGA and the microbeads assay confirmed granulocyte-reactivity in 83 cases with 70 matching results (κ = 0.742). However, out of six detected human neutrophil antigen (HNA) reactivities only two specificities matched in both assays. CONCLUSION: Flow-WIFT may be a valuable addition to GIFT for granulocyte-reactive antibody screening. MAIGA remains the most reliable laboratory method for antibody specification.


Assuntos
Testes de Aglutinação/métodos , Anticorpos Monoclonais/imunologia , Granulócitos/imunologia , Especificidade de Anticorpos , Humanos
3.
Forensic Sci Int Genet ; 13: 134-42, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25117402

RESUMO

The DNA Commission of the International Society of Forensic Genetics (ISFG) regularly publishes guidelines and recommendations concerning the application of DNA polymorphisms to the question of human identification. Previous recommendations published in 2000 addressed the analysis and interpretation of mitochondrial DNA (mtDNA) in forensic casework. While the foundations set forth in the earlier recommendations still apply, new approaches to the quality control, alignment and nomenclature of mitochondrial sequences, as well as the establishment of mtDNA reference population databases, have been developed. Here, we describe these developments and discuss their application to both mtDNA casework and mtDNA reference population databasing applications. While the generation of mtDNA for forensic casework has always been guided by specific standards, it is now well-established that data of the same quality are required for the mtDNA reference population data used to assess the statistical weight of the evidence. As a result, we introduce guidelines regarding sequence generation, as well as quality control measures based on the known worldwide mtDNA phylogeny, that can be applied to ensure the highest quality population data possible. For both casework and reference population databasing applications, the alignment and nomenclature of haplotypes is revised here and the phylogenetic alignment proffered as acceptable standard. In addition, the interpretation of heteroplasmy in the forensic context is updated, and the utility of alignment-free database searches for unbiased probability estimates is highlighted. Finally, we discuss statistical issues and define minimal standards for mtDNA database searches.


Assuntos
Impressões Digitais de DNA/normas , DNA Mitocondrial/genética , Genética Forense/normas , Laboratórios/normas , Interpretação Estatística de Dados , Bases de Dados de Ácidos Nucleicos , Genética Populacional , Haplótipos , Humanos , Filogenia , Controle de Qualidade , Alinhamento de Sequência/normas , Análise de Sequência de DNA/normas , Sociedades Científicas
4.
Vox Sang ; 107(2): 200-3, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24712334

RESUMO

Granulocyte-reactive antibodies may cause transfusion-related acute lung injury (TRALI) and immune neutropenias. Risk factors for their acquisition other than previous alloexposition are largely unknown. In addition to the known association between human leucocyte antigen alloantibodies and red blood cell alloimmunization in selected cohorts of transfused patients, this study investigated a possible extension of this association to granulocyte-reactive antibodies in women with a history of pregnancy. The overall prevalence of granulocyte-reactive antibodies in 333 samples from women with a history of pregnancy (143 samples containing red cell alloantibodies) was 23·1%. The prevalence in the red cell-alloimmunized group (32·9%) was significantly higher than in controls (15·8%, P < 0·001). This could suggest that some individuals may be strong immunological responders, forming alloantibodies more readily than others.


Assuntos
Eritrócitos/imunologia , Granulócitos/imunologia , Isoanticorpos/sangue , Adulto , Estudos de Casos e Controles , Feminino , Antígenos HLA/imunologia , Humanos , Gravidez , Prevalência , Reação Transfusional
6.
Forensic Sci Int Genet ; 6(6): 679-88, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22864188

RESUMO

DNA profiling of biological material from scenes of crimes is often complicated because the amount of DNA is limited and the quality of the DNA may be compromised. Furthermore, the sensitivity of STR typing kits has been continuously improved to detect low level DNA traces. This may lead to (1) partial DNA profiles and (2) detection of additional alleles. There are two key phenomena to consider: allelic or locus 'drop-out', i.e. 'missing' alleles at one or more genetic loci, while 'drop-in' may explain alleles in the DNA profile that are additional to the assumed main contributor(s). The drop-in phenomenon is restricted to 1 or 2 alleles per profile. If multiple alleles are observed at more than two loci then these are considered as alleles from an extra contributor and analysis can proceed as a mixture of two or more contributors. Here, we give recommendations on how to estimate probabilities considering drop-out, Pr(D), and drop-in, Pr(C). For reasons of clarity, we have deliberately restricted the current recommendations considering drop-out and/or drop-in at only one locus. Furthermore, we offer recommendations on how to use Pr(D) and Pr(C) with the likelihood ratio principles that are generally recommended by the International Society of Forensic Genetics (ISFG) as measure of the weight of the evidence in forensic genetics. Examples of calculations are included. An Excel spreadsheet is provided so that scientists and laboratories may explore the models and input their own data.


Assuntos
Alelos , Impressões Digitais de DNA/normas , Funções Verossimilhança , Repetições de Microssatélites , DNA/genética , Genética Forense , Humanos , Sociedades Científicas
7.
Vox Sang ; 102(3): 234-42, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22098427

RESUMO

BACKGROUND AND OBJECTIVES: One to two per cent of patients in need of red cell transfusion carry irregular antibodies to red blood cell (RBC) antigens and have to be supplied with specially selected blood units. To be able to respond to those requests, blood centres have to screen a significant number of donors for a variety of antigens serologically, which is a costly and through the shortage of reagents, also limited procedure. To make this procedure more efficient, the Austrian Red Cross has developed a genotyping assay as an alternative approach for high throughput RBC typing. MATERIALS AND METHODS: A multiplex polymerase chain reaction (PCR) assay was designed for typing 35 RBC antigens in six reaction mixes. The assay includes both common as well as high-frequency-alleles: MNS1, MNS2, MNS3 and MNS4; LU1, LU2, LU8 and LU14; KEL1, KEL2, KEL3, KEL4, KEL6, KEL7, KEL11, KEL17 and KEL21; FY1, FY2, FYB(WK) and FY0 (FYB(ES)); JK1 and JK2; DI1, DI2, DI3 and DI4; YT1 and YT2; DO1 and DO2; CO1 and CO2; IN1 and IN2. The assay was validated using 370 selected serologically typed samples. Subsequently 6000 individuals were screened to identify high frequency antigen (HFA)-negative donors and to facilitate the search for compatible blood for alloimmunized patients. RESULTS: All controls showed complete concordance for the tested markers. The screening of 6000 donors revealed 57 new HFA-negative donors and the blood group database was extended by approximately 210,000 results. CONCLUSION: The study shows that in practice, this high-throughput genotyping assay is feasible, fast and provides reliable results. Compared to serological testing, this molecular approach is also very cost-efficient.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Tipagem e Reações Cruzadas Sanguíneas/métodos , Técnicas de Genotipagem/métodos , Reação em Cadeia da Polimerase/métodos , Alelos , Feminino , Humanos , Masculino
8.
Bone Marrow Transplant ; 47(2): 172-80, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21460872

RESUMO

Between 1988 and 2007, international searches for matched unrelated donors (MUDs) were performed for 1586 Austrian patients. Between 2004 and 2007, a MUD was identified for 76.7% of the patients. Between 1996 and 2003, a donor was identified for 71.3% of the patients, and between 1988 and 1995, only for 53.4% of the patients. Search times of successful searches decreased from 7.7 months in the first period to 1.7 months in the period from 2004 to 2007. However, transplants were not performed in all cases in which a donor was found: only in 61.6% of the patients between 2004 and 2007, in 53.4% between 1996 and 2003 and in 29.6% between 1988 and 1995. Multivariate analysis determined that having a common HLA type was the most important variable impacting on finding a MUD for a patient. Factors that most strongly influence a patient's access to transplant were the patient's European origin and a short time between diagnosis and start of donor search. The strongest factor for both finding a donor and being transplanted was a search being performed during more recent years: patients' chances increased from year to year.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Doadores Vivos/provisão & distribuição , Obtenção de Tecidos e Órgãos/métodos , Doadores não Relacionados/provisão & distribuição , Adulto , Áustria , Criança , Feminino , Antígenos HLA/genética , Antígenos HLA/imunologia , Humanos , Doadores Vivos/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Fenótipo , Doadores não Relacionados/estatística & dados numéricos
10.
Forensic Sci Int Genet ; 5(5): 501-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21106449

RESUMO

The use of non-human DNA typing in forensic science investigations, and specifically that from animal DNA, is ever increasing. The term animal DNA in this document refers to animal species encountered in a forensic science examination but does not include human DNA. Non-human DNA may either be: the trade and possession of a species, or products derived from a species, which is contrary to legislation; as evidence where the crime is against a person or property; instances of animal cruelty; or where the animal is the offender. The first instance is addressed by determining the species present, and the other scenarios can often be addressed by assigning a DNA sample to a particular individual organism. Currently there is little standardization of methodologies used in the forensic analysis of animal DNA or in reporting styles. The recommendations in this document relate specifically to animal DNA that is integral to a forensic science investigation and are not relevant to the breeding of animals for commercial purposes. This DNA commission was formed out of discussions at the International Society for Forensic Genetics 23rd Congress in Buenos Aires to outline recommendations on the use of non-human DNA in a forensic science investigation. Due to the scope of non-human DNA typing that is possible, the remit of this commission is confined to animal DNA typing only.


Assuntos
Crime , DNA/genética , Genética Forense , Acreditação , Animais , Frequência do Gene , Humanos , Laboratórios/normas
11.
Vox Sang ; 100(1): 99-111, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21175660

RESUMO

Plasmodium falciparum malaria has long been a killer of the young, and has selected for polymorphisms affecting not only erythrocytes, but the immunogenetics of three histocompatibility systems: ABO, human leukocyte antigen (HLA), and CD36. The ABO system is important because the original allele, encoding glycosylation with the A sugar, acts as an adhesion ligand with infected red blood cells (iRBC), thereby promoting vasoocclusion. The prevalence of blood group O, which reduces this cytoadhesion, has increased in endemic areas. Other adaptations which could mitigate A-mediated rosetting include weaker A expression and increased soluble A secretion. The role of the HLA system in malaria has been harder to verify. Although HLA-B53 and DRB1*04 may be associated with clinical outcome, HLA studies are challenged by numerous comparisons in this most polymorphic of systems, and confounded by increasingly heterogeneous populations. Certain HLA markers may also reflect linkage artefact with other malaria-relevant polymorphisms. HLA may be less important because the parasite predominantly invades a compartment which does not express HLA. Adhesion of iRBCs is also mediated by CD36, expressed on platelets, monocytes, and microvascular endothelium. CD36 on monocytes is involved in clearing iRBC, while CD36 on platelets and the endothelium may play a role in tissue sequestration. The genetics of CD36 expression are complex, and recent research is fraught with inconsistent results. The solution may lie in examining genotype-phenotype correlations, zygosity effects on differential tissue expression, or other mechanisms altering CD36 tissue expression. Carefully designed prospective studies should bridge the gap between in-vitro observations and clinical outcomes.


Assuntos
Malária Falciparum/genética , Malária Falciparum/imunologia , Sistema ABO de Grupos Sanguíneos/genética , Animais , Evolução Biológica , Antígenos CD36/genética , Predisposição Genética para Doença , Antígenos HLA/genética , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/imunologia , Humanos , Fenômenos Imunogenéticos , Modelos Genéticos , Mutação , Plasmodium falciparum/imunologia , Plasmodium falciparum/patogenicidade
14.
Bone Marrow Transplant ; 45(5): 846-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20348972

RESUMO

The WHO Nomenclature Committee for Factors of the HLA System met during the 15th International Histocompatibility and Immunogenetics Workshop in Buzios, Brazil in September 2008. This update is an extract of the main report that documents the additions and revisions to the nomenclature of human leukocyte antigen (HLA) specificities following the principles established in previous reports.


Assuntos
Antígenos HLA , Terminologia como Assunto , Organização Mundial da Saúde , Humanos
16.
Tissue Antigens ; 72(5): 499-500, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18937795

RESUMO

Sequencing analysis of exons 1-3 of the human leukocyte antigen (HLA)-C gene showed a novel allele, HLA-Cw*0617. While the amino acid sequence is identical with the HLA-Cw*060201 allele, the leader peptide differs in three amino acids.


Assuntos
Éxons/genética , Antígenos HLA-C/genética , Alelos , Sequência de Bases , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência
20.
Tissue Antigens ; 69 Suppl 1: 210-3, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17445203

RESUMO

A proposal for a standardized nomenclature for human leukocyte antigen (HLA) microsatellites is presented. It provides recommendations for Microsatellites as regards to locus name, primer names, and denominations for alleles.


Assuntos
Antígenos HLA/genética , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe I/genética , Repetições de Microssatélites/genética , Terminologia como Assunto , Alelos , Primers do DNA , Humanos
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