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❶The unusual origin of the polymerase chain reaction. From Drowkin et al,

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The PCR Process

The ability to map DNA methylation patterns across the genome. The ability to map the bound histone modifications and other proteins bound to chromatin across the genome. The ability to analyze gene expression changes with changes in chromatin modifications. The ability to associate single-nucleotide polymorphisms with various disease states. The correct answer is B: Protein structure abnormalities b. Specific chromosome copy number aberrations c. Presence of specific antigens d. What is the FISH probe composed of?

Qualitative PCR is a good technique to use when PCR is performed for cloning purposes or for identification of a pathogen. It is able to indicate how much of a specific DNA or gene is present in the sample. The most widely used method of analysis of the PCR product is via the use of the simple agarose gel electorophoresis.

The agarose gel electrophoresis is the easiest and most common method of visualizing and analyzing the PCR product. It allows the determination of the presence and the size of the PCR product. A predetermined set of DNA products with known sizes are ran on the gel as molecular markers to help determine the size of the product.

The two other methods for visualizing the PCR products are staining of the amplified DNA product using a chemical dye such as ethidium bromide, which intercalates between the two strands of the duplex or labeling the PCR primers or nucleotides with fluorescent dyes fluorophores prior to PCR amplification.

PCR allows the creation of billions of copies of a specific DNA fragment or gene, which allows for detection and identification of gene sequences using visual techniques based on size and charge. It is a highly sensitive technique and can allow results within a shorter time frame than most molecular techniques. The PCR process can be divided into three main steps. The denaturation process allows the solution to be heated above the melting point of the two complementary strands of the template DNA, which allows the strands to separate.

Then the annealing process allows the primers to bind to the specific DNA segment. The annealing between the primers and the template DNA occurs only if they are complementary in sequence. The temperature is raised again at which time the DNA polymerase is able to extend the primers by adding nucleotides to the developing DNA strand, known as transcription.

With each repeat of these three steps, the number of copied DNA molecules is doubled. Differences in survival between two treatment groups are best compared using which of the following statistical methods? The intraclass correlation coefficent representing the best degree of agreement between two diagnostic tools among the following is:.

For details see the December issue of JID. The basic methodological steps of NGS include: Applications of NGS in medicine include: The target molecule type for Southern blotting is: Actively transcribed regions of DNA to which transcription factors actively bind B. The core structure around which base pairs of DNA bind C. Constitutively closed and transcriptionally repressed areas of genome organization D.

The ability to map DNA methylation patterns across the genome B. The ability to map the bound histone modifications and other proteins bound to chromatin across the genome C.

The ability to analyze gene expression changes with changes in chromatin modifications D. The ability to associate single-nucleotide polymorphisms with various disease states The correct answer is B: In a fluorescent by fluorescent scatter plot, cells present in the upper right quadrant of the plot are generally:. B Side scatter provides information that correlates to the cell granularity while forward scatter is a marker of cell size. With the aid of these two parameters and a few other stains, commercial blood analyzers are able to generate complete blood counts CBC with differentials.

Remember, flow cytometry cannot provide information on tissue architecture or cell-cell interactions, as the cells must be suspended in solution for flow analysis. Flow cytometry can provide information on cell surface markers and intracellular signaling, but this is performed using fluorophore labeled antibodies, while measuring SSC and FSC does not require antibodies.

C Gating refers to the process of selecting cell subsets of interest from parent populations during flow cytometry data analysis.

The field that the cells enter for a sorting is usually an electromagnetic field that separates based on charge. D The interpretation of the basic fluorescent by fluorescent scatter plot is important, as virtually all flow experiments employ them. Cells in the upper right are positive for both markers, while cells in the bottom left are generally negative for both markers.

The other two quadrants are negative for one marker and positive for the other as depicted in Figure 1ciii. Also, the axes for fluorescent by fluorescent plots are displayed logarithmically, meaning that even small visual differences reflect potentially large differences in fluorophore expression. By subscribing to the newsletter, you can: I still love quizzes. View all new posts on JID Jottings each month. Be introduced to up-and-coming investigators through Meet the Investigator, a monthly Facebook feature.

View presentations that review and explain the fundamentals of skin biology through the Skin Biology Lecture Series. Keep up with current events in the research dermatology community. Study designs used for comparative effectiveness research include: The intraclass correlation coefficent representing the best degree of agreement between two diagnostic tools among the following is: Increase in the optical resolution and contrast of the image c.

Ability to reconstruct a 3-D image of the specimen d. Ability to collect serial optical sections from thick specimens e.

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The advent of the polymerase chain reaction (PCR) radically transformed biological science from the time it was first discovered (Mullis, ). For the first time, it allowed for specific detection and production of large amounts of DNA.

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The ELISPOT assay is a highly sensitive, relatively easy-to-perform, and reproducible method for identification and quantification of even very rare antigen-specific T cells.

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Collective cell migration is a hallmark of wound repair, cancer invasion and metastasis, immune responses, angiogenesis, and embryonic morphogenesis. These include transcriptome analysis with RNA sequencing (RNA-seq) (Antonini et al., x Antonini et al., Antonini, D., Mollo, M.R., and Missero, C. Research techniques made simple: identification and characterization of long noncoding RNA in dermatological research.

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The questions and answers below relate to the Research Techniques Made Simple article “Enzyme Immunoassay (EIA) and Enzyme-Linked Immunosorbent Assay (ELISA),” published online with the September issue of JID. Correct answers appear in bold . RNA sequencing is a method of transcriptome profiling that utilizes next-generation sequencing technology. It offers several distinct advantages over hybridization-based approaches, most notably superior sensitivity and the capacity for de novo transcript discovery. This article describes RNA sequencing methodology, summarizes important technological advances and challenges, and .