Background: The presence of clinically relevant mutations in KRAS and NRAS genes determines the response of anti-epidermal growth factor receptor antibody therapy for metastatic colorectal cancer (mCRC). The only quantitative polymerase chain reaction (qPCR)-based diagnostic tests approved by the Food and Drug Administration (FDA) screen merely for mutations in codons 12 and 13 of KRAS. Objective: The objective of the study was to study the frequency of clinically relevant mutations in KRAS and NRAS genes that are not included in FDA-approved qPCR tests. Methods: Formalin-fixed paraffin-embedded tumor specimens from 1113 mCRC Mexican patients from different health institutions across the country were analyzed by Sanger sequencing for KRAS mutations in exons 2, 3, and 4. Furthermore, 83 were analyzed in exons 2, 3, and 4 of NRAS. Results: From the specimens tested for KRAS, 33.69% harbored a mutation. From these, 71.77% were in codon 12 and 27.69% in codon 13 (both located in exon 2). Codons 59 (exon 3) and 146 (exon 4) accounted for the remaining 0.54%. From the 83 specimens, in which NRAS was analyzed, three mutations were found in codon 12 (3.61%). Approximately 6% of RAS mutated specimens would have been falsely reported as RAS wild type if an FDA-approved qPCR diagnostic test had been used. Conclusions: While these kits based on qPCR can be very practical and highly sensitive, their mutation coverage ignores mutations from poorly genetically characterized populations. (REV INVEST CLIN. [AHEAD OF PRINT]
Influenza A/H5N1 represents a potential risk of a worldwide pandemic event, and as we have witnessed in past influenza outbreaks, the current production chains for vaccination cannot supply the demand for emergencies such as these. Limiting factors include the need for eggs and active virus handling as well as turnaround time and cost. Most of the influenza AH5N1 cases are contained in poultry; however, risk of zoonosis and spread of the virus in humans grows by the day, thus, a mass-produced fast-responding preventive vaccine is required. In this article, we describe the production of a recombinant HA1 subunit of influenza AH5N1 hemagglutinin as a potential key ingredient of a new avian vaccine, using a prokaryotic biotechnological platform. This system is potentially faster, cheaper, and more efficient than current means of vaccine production.
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