Publication
Assessment of the viability of using Semiquant PSA quantification with SERATECĀ® SeraQuantTM as a confirmatory test for traces of semen in a forensic genetics laboratory : Idealization, development and validation of a method
| dc.contributor.advisor | Silva, Alexandra Maia e | |
| dc.contributor.advisor | Ferreira, Paulo Miguel | |
| dc.contributor.author | Medeiros, Raquel | |
| dc.date.accessioned | 2025-01-06T16:16:41Z | |
| dc.date.available | 2025-01-06T16:16:41Z | |
| dc.date.issued | 2024-12-13 | |
| dc.description | DissertaĆ§Ć£o para obtenĆ§Ć£o do grau de Mestre no Instituto UniversitĆ”rio Egas Moniz | pt_PT |
| dc.description.abstract | Os crimes sexuais representam uma grave violaĆ§Ć£o dos direitos humanos e tĆŖm um impacto profundo nas vĆtimas e na sociedade. Eles correspondem a 10% dos crimes investigados pela PolĆcia JudiciĆ”ria (PJ). Conforme especificado no CĆ³digo Penal portuguĆŖs (CP), os crimes de natureza sexual sĆ£o distinguidos em dois grupos: crimes contra a liberdade sexual (artigos 163.Āŗ a 170.Āŗ) e crimes contra a autodeterminaĆ§Ć£o sexual (artigos 171.Āŗ a 176.Āŗ-C). Ao realizar um exame forense de um crime sexual, o vestĆgio biolĆ³gico mais importante a se procurar Ć© o sĆ©men. Este fluĆdo Ć© essencial nestes tipos de crimes, pois fornece uma prova incontestĆ”vel de que um ato sexual foi cometido. Por esta razĆ£o, o Setor de Biologia (BBG) do LaboratĆ³rio de PolĆcia CientĆfica da PolĆcia JudiciĆ”ria (LPC-PJ) tem investido em novos mĆ©todos e equipamentos para facilitar a identificaĆ§Ć£o de sĆ©men pelos peritos forenses. Neste trabalho, foi desenvolvido um mĆ©todo utilizando o instrumento SERATECĀ® SeraQuant Reader para os testes semi-quantitativos do AntĆgeno ProstĆ”tico EspecĆfico (PSA). Para avaliar se este mĆ©todo poderia-se tornar um teste confirmatĆ³rio, amostras de casos reais foram analisadas na fase de observaĆ§Ć£o do fluxo de trabalho do BBG e os resultados obtidos nessa fase foram registados. Quarenta e oito amostras foram adquiridas de 25 exames de crimes sexuais e uma sĆ©rie de estudos de concordĆ¢ncia foram realizados entre os resultados dos testes preliminares, o teste confirmatĆ³rio e os perfis obtidos na anĆ”lise de Ć”cido desoxirribonucleico (ADN), com o objetivo de identificar possĆveis relaƧƵes. AlĆ©m disso, o instrumento foi validado internamente realizando-se testes de sensibilidade, especificidade, reprodutibilidade e repetibilidade. Para as 48 amostras dos casos reais, os estudos de concordĆ¢ncia demonstraram que, entre os valores de quantificaĆ§Ć£o do PSA e os perfis da fraĆ§Ć£o masculina (FM), cerca de 89% das amostras com alta concentraĆ§Ć£o de PSA (acima de 4,1 ng/mL) estavam em concordĆ¢ncia com o perfil de ADN obtido na FM (masculino ou mistura). Por outro lado, quase 87% das amostras que foram negativas para sĆ©men apresentaram resultados positivos para PSA. Os resultados obtidos nos testes de sensibilidade, especificidade, reprodutibilidade e repetibilidade permitiram validar internamente o SeraQuant Reader. | pt_PT |
| dc.description.abstract | Sexual crimes represent a serious violation of human rights and have a profound impact on the victims and in society, they represent 10% of the crimes investigated by the PolĆcia JudiciĆ”ria (PJ). As specified in the Portuguese CĆ³digo Penal (CP) crimes of sexual nature are distinguished in two groups: crimes against sexual freedom (article 163.Āŗ to 170.Āŗ) and crimes against sexual self-determination (article 171.Āŗ to 176.Āŗ-C). When performing a forensic exam of a sexual crime, the most important biological trace to look for is semen. This fluid is essential in these types of crimes, because it gives undeniable proof that a sexual act was committed. Therefore, the Biology Sector (BBG) of the LaboratĆ³rio de PolĆcia CientĆfica da PolĆcia JudiciĆ”ria (LPC-PJ) has been investing new methods and equipment is to ease the identification of semen for the forensic experts. In this work, a method using the SERATECĀ® SeraQuant Reader instrument was developed for the Prostate-specific Antigen (PSA) Semiquant tests. In order to evaluate if this method could become a confirmatory test, real casework samples were analysed in the observation stage of the BBG workflow and the results obtained in this stage were recorded. Forty-eight samples were acquired from 25 exams of sexual crimes and a series of concordance studies were made between the preliminary tests results, the confirmatory test and the profiles obtained in the deoxyribonucleic acid (DNA) analysis with the aim of identifying possible relations. Furthermore, the instrument was internally validated by performing sensitivity, specificity, reproducibility and repeatability tests. For the 48 real casework samples, the concordance studies demonstrated that between the PSA quantification values and the Male fraction (MF) profiles, nearly 89% of the samples with high PSA concentration (above 4,1 ng/mL) were in concordance with the male or mixed DNA profile that was obtained in the MF on the other hand, almost 87% of the samples that were negative for semen had positive results for PSA. The results obtained for sensitivity, specificity, reproducibility and repeatability tests allowed to internally validate the SeraQuant Reader. | pt_PT |
| dc.identifier.tid | 203759893 | pt_PT |
| dc.identifier.uri | http://hdl.handle.net/10400.26/53481 | |
| dc.language.iso | eng | pt_PT |
| dc.subject | SĆ©men | pt_PT |
| dc.subject | AntĆgeno prostĆ”tico especĆfico | pt_PT |
| dc.subject | ValidaĆ§Ć£o interna | pt_PT |
| dc.subject | Crimes sexuais | pt_PT |
| dc.subject | SERATECĀ® | pt_PT |
| dc.title | Assessment of the viability of using Semiquant PSA quantification with SERATECĀ® SeraQuantTM as a confirmatory test for traces of semen in a forensic genetics laboratory : Idealization, development and validation of a method | pt_PT |
| dc.type | master thesis | |
| dspace.entity.type | Publication | |
| rcaap.rights | openAccess | pt_PT |
| rcaap.type | masterThesis | pt_PT |
| thesis.degree.name | Mestrado em Tecnologias Laboratoriais em CiĆŖncias Forenses | pt_PT |