RESUMEN
BACKGROUND: Rapid and accurate detection of viral respiratory infections is important for infection control measures. This study compares the analytical and clinical performance of the Xpert® Xpress CoV-2/Flu/RSV plus test ("Xpert", Cepheid) and the STANDARD™ M10 Flu/RSV/SARS-CoV-2 test ("M10", SD Biosensor). Both tests are quadruplex RT-PCR assays for rapid diagnosis of SARS-CoV-2, influenza A/B and RSV. STUDY DESIGN: Analytical sensitivities were determined by limit of detection for SARS-CoV-2, influenza A, influenza B and RSV, respectively. Additionally, the clinical performance of the Xpert and the M10 tests was evaluated against standard-of-care RT-PCR by testing of 492 clinical specimens. RESULTS: The analytical sensitivities for Xpert versus M10 test was 10, 50, 50 and 300 versus 300, 200, 800 and 1500 copies/mL for SARS-CoV-2, influenza A, influenza B and RSV, respectively. Clinical sensitivity for the Xpert test was superior across all four pathogens compared to the M10 test. Xpert showed clinical sensitivity of 100 % in all Ct-ranges for all four pathogens whereas M10 showed clinical sensitivity of 100 % in the 25-30 Ct-range, 84-100 % in the 30-35 Ct-range and 47-67 % in the >35 Ct-range across the four pathogens. Translating into real-life clinical sensitivity, the Xpert would detect 100 % of all four pathogens, whereas M10 would detect 92.1, 92.4, 84.8 and 94.7 % for SARS-CoV-2, influenza A, influenza B and RSV. CONCLUSION: This study demonstrates improved analytical and clinical performance of Xpert Xpress CoV-2/Flu/RSV plus compared to STANDARD M10 Flu/RSV/SARS-CoV-2, which is important for ensuring accuracy of diagnosis at all stages of a respiratory infection.
Asunto(s)
COVID-19 , Virus de la Influenza A , Virus de la Influenza B , Gripe Humana , Infecciones por Virus Sincitial Respiratorio , SARS-CoV-2 , Sensibilidad y Especificidad , Humanos , COVID-19/diagnóstico , COVID-19/virología , Gripe Humana/diagnóstico , Gripe Humana/virología , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Virus de la Influenza B/aislamiento & purificación , Virus de la Influenza B/genética , Virus de la Influenza A/aislamiento & purificación , Virus de la Influenza A/genética , Infecciones por Virus Sincitial Respiratorio/diagnóstico , Infecciones por Virus Sincitial Respiratorio/virología , Pruebas en el Punto de Atención , Prueba de Ácido Nucleico para COVID-19/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Virus Sincitial Respiratorio Humano/genética , Virus Sincitial Respiratorio Humano/aislamiento & purificaciónRESUMEN
Several studies point to the placenta as the primary cause of pre-eclampsia. Our objective was to identify placental genes that may contribute to the development of pre-eclampsia. RNA was purified from tissue biopsies from eleven pre-eclamptic placentas and eighteen normal controls. Messenger RNA expression from pooled samples was analysed by microarrays. Verification of the expression of selected genes was performed using real-time PCR. A surprisingly low number of genes (21 out of 15,000) were identified as differentially expressed. Among these were genes not previously associated with pre-eclampsia as bradykinin B1 receptor and a 14-3-3 protein, but also genes that have already been connected with pre-eclampsia, for example, inhibin beta A subunit and leptin. A low number of genes were repeatedly identified as differentially expressed, because they may represent the endpoint of a cascade of events effectuated throughout gestation. They were associated with transcriptional regulation and vasoregulative pathways, along with a number of hypothetical proteins and gene sequences with unknown functions.
Asunto(s)
Perfilación de la Expresión Génica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Placenta/fisiología , Preeclampsia/genética , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Hipertensión/genética , Recién Nacido , Inflamación/genética , Subunidades beta de Inhibinas/biosíntesis , Subunidades beta de Inhibinas/genética , Masculino , Estrés Oxidativo/genética , Placenta/química , Preeclampsia/metabolismo , Embarazo , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estadísticas no ParamétricasRESUMEN
BACKGROUND: The interaction between epithelial cells of endometrium and trophoblast cells during implantation is presumed to be accompanied by a change in gene expression in the cell types involved. The objective of this study was to identify such differentially expressed genes. METHODS: The interaction between the cell types was simulated in vitro by growing primary cell cultures of human endometrial epithelial cells and trophoblast cells together (co-culture) and separately (control cultures). Gene expression in the cell cultures was compared using the Differential Display method and confirmed using a modified Northern Blot method. RESULTS: Twelve transcripts were identified as being differentially expressed following the interaction between trophoblast and endometrial cells. Some of these sequences show homology to known human genes while other sequences are coding for potential novel genes: (1) one sequence was homologous to the to Homer 1 gene, (2) one identical to the mRNA for XP-G factor, (3) one similar to a hypothetical protein, (4) transcripts showing homologies to a mRNA coding for a cellular proapoptotic protein, and (5) sequences homologous to regions on human chromosomes 5 and 16. Besides, some differentially expressed transcripts have sequences, which could be translated into ribosomal proteins or possibly code for novel proteins. CONCLUSION: These sequences may be important to the course of events following the interaction between endometrial epithelial and trophoblast cells and responsible for implantation.
Asunto(s)
Comunicación Celular/fisiología , Endometrio/fisiología , Regulación de la Expresión Génica/fisiología , Trofoblastos/fisiología , Northern Blotting/métodos , Comunicación Celular/genética , Técnicas de Cocultivo , Endometrio/citología , Células Epiteliales/citología , Células Epiteliales/fisiología , Femenino , Expresión Génica , Perfilación de la Expresión Génica/métodos , Humanos , Embarazo , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Trofoblastos/citologíaRESUMEN
PROBLEM: The expression of the non-classical human leukocyte antigen (HLA) class Ib gene, HLA-G, seems to be important at the feto-maternal interface. The HLA-G molecule is almost monomorphic and expressed in both membrane-bound and soluble isoforms. It has been shown to inhibit natural killer cell -mediated lysis and influence cytokine expression. HLA-G gene polymorphism has been linked to differences in gene expression profile of alternatively spliced HLA-G transcripts and levels of specific HLA-G messenger RNA (mRNA) isoforms. Furthermore, aberrant HLA-G expression has been reported in preeclamptic placentas. On this background it is of general interest to further elucidate any associations between HLA-G polymorphism and protein expression. METHODS: We have investigated HLA-G protein expression by immunohistochemistry in HLA-G genotyped placentas from term. HLA-G mRNA expression in preeclamptic placentas and in control placentas was also studied by microarray technology. RESULTS AND CONCLUSIONS: The studies of HLA-G protein expression in term placentas by immunohistochemical analysis showed no clear associations with HLA-G genotypes although this could be because of the very semi-quantitative nature of this technique. However, we found a tendency towards reduction of HLA-G mRNA expression in placentas from preeclamptic cases compared to matched controls with the use of microarray technology.