RESUMO
The isolation of pure nucleic acids from clinical samples is a crucial step in the molecular diagnosis of viral infections by nucleic acid testing (NAT). In this study, novel flat glass devices (cards) were demonstrated to support the rapid and efficient extraction of nucleic acids from upper respiratory tract specimens (nasal washes and swabs). The performance of the nucleic acid extraction cards was directly compared to an existing standardized and automated platform for viral extraction from these types of specimens. The flowthrough card method improved the speed of nucleic acid purification and accommodated larger sample volumes in extraction of bacteriophage MS2 RNA from the various specimen matrices. The dynamic range and estimated sensitivity of the card extraction method for reverse transcriptase quantitative real-time PCR (RT-qPCR)-based detection approximate those of the standardized magnetic glass bead extraction method used in this study.
Assuntos
Secreções Corporais/virologia , Levivirus/isolamento & purificação , RNA Viral/isolamento & purificação , Sistema Respiratório , Virologia/métodos , Automação/métodos , Equipamentos e Provisões , Vidro , Humanos , Levivirus/genética , RNA Viral/genética , Sensibilidade e EspecificidadeRESUMO
To understand how the brain processes sensory information to guide behavior, we must know how stimulus representations are transformed throughout the visual cortex. Here we report an open, large-scale physiological survey of activity in the awake mouse visual cortex: the Allen Brain Observatory Visual Coding dataset. This publicly available dataset includes the cortical activity of nearly 60,000 neurons from six visual areas, four layers, and 12 transgenic mouse lines in a total of 243 adult mice, in response to a systematic set of visual stimuli. We classify neurons on the basis of joint reliabilities to multiple stimuli and validate this functional classification with models of visual responses. While most classes are characterized by responses to specific subsets of the stimuli, the largest class is not reliably responsive to any of the stimuli and becomes progressively larger in higher visual areas. These classes reveal a functional organization wherein putative dorsal areas show specialization for visual motion signals.