Rapid reverse transcriptase recombinase polymerase amplification assay for flaviviruses using non-infectious in vitro transcribed RNA as positive controls.

West Nile virus (WNV) and Wesselsbron virus (WSLV) are mosquito-borne viruses belonging to the Flavivirus genus, family Flaviviridae and cause outbreaks in southern Africa after heavy rain. Isothermal assays have been proposed for application in field situations as well as low resource settings and hence we developed a reverse-transcriptase recombinase polymerase amplification (RT-RPA) to detect WNV and WSLV known to occur in South Africa, causing sporadic outbreaks usually associated with good rainfall favouring mosquito breeding. Infectious virus can only be handled within a biosafety level (BSL) 3 facility, hence we opted to validate the assay with transcribed RNA. Specific RT-RPA primers and probes were designed for detection of WNV and WSLV and products detected using a rapid lateral flow device. The assay was performed in 30 min and detected 1.9 × 10¹ copies of WNV and 3.5 × 10° copies WSLV using noninfectious transcribed RNA controls. In addition, the assay was not inhibited by the presence of mosquito extracts in spiked samples. Mismatches between the WNV and WSLV probes and other flaviviruses will likely prevent cross reactivity. The sensitivity, low RPA incubation temperature and rapid processing time makes assay systems based on RPA technology ideally suited for fieldable diagnostics.

Thermal History Mapping in Powder Bed Laser Sintering at the Micrometer Scale.

A thermal sensor was used to better understand parameters which influenced the interaction between a laser beam and a 0.5% Mn-doped ZnAl2.2O4 material, especially the laser defocusing parameter. The optical properties of the material depend on whether the Mn2+ ions occupy octahedral and/or tetrahedral sites depending on thermal history. A screen printing process is performed to obtain material thin films. Laser irradiation of the films was carried out (patterning 1 cm length single laser track) with different z defocusing heights. Luminescence properties around laser tracks led to the thermal history determination at the micrometer scale. It was shown that spatial thermal gradients defined at the micrometer scale perpendicularly to the borders of the laser tracks could be semiquantified for different z conditions. Laser defocusing leads to decrease thermal gradients as confirmed by thermal modeling studies.

Alterations in Homologous Recombination-Related Genes and Distinct Platinum Response in Metastatic Triple-Negative Breast Cancers: A Subgroup Analysis of the ProfiLER-01 Trial.

BACKGROUND: a specific subset of metastatic triple-negative breast cancers (mTNBC) is characterized by homologous recombination deficiency (HRD), leading to enhanced sensitivity to platinum-based chemotherapy. Apart from mutations in BRCA1/2 genes, the evaluation of other HRD-related alterations has been limited to date. As such, we analyzed data from mTNBC patients enrolled in the ProfiLER-01 study to determine the prevalence of alterations in homologous recombination-related (HRR) genes and their association with platinum sensitivity. METHODS: next-generation sequencing and promoter methylation of BRCA1 and RAD51C were performed on tumors from patients with mTNBC, using a panel of 19 HRR genes. Tumors were separated into three groups based on their molecular status: mutations in BRCA1/2, mutations in other HRR genes (BRCA1/2 excluded) or BRCA1/RAD51C promoter methylation and the absence of molecular alterations in HRR genes (groups A, B and C, respectively). Sensitivity to platinum-based chemotherapy was evaluated through the radiological response. RESULTS: mutations in BRCA1/2 were detected in seven (13.5%) patients, while alterations in other HRR genes or hypermethylation in BRCA1 or RAD51C were reported in 16 (30.7%) patients; furthermore, no alteration was found in the majority of patients (n = 29; 55.8%). Among 27 patients who received platinum-based chemotherapy, the disease control rate was 80%, 55% and 18% (groups A, B and C, respectively; p = 0.049). Regarding group B, patients with disease control exhibited mutations in FANCL, FANCA and the RAD51D genes or RAD51C methylation; Conclusion: mutations in HRR genes and epimutations in RAD51C were associated with disease control through platinum-based chemotherapy. As such, apart from well-characterized alterations in BRCA1/2, a more comprehensive evaluation of HRD should be considered in order to enlarge the selection of patients with mTNBC that could benefit from platinum-based chemotherapy.