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In the August 1 issue of CELL, researchers from the Gene and Stem Cell Therapy Program at Sydney's Centenary Institute revealed another function of introns, or noncoding nucleotide sequences, in DNA. They reported that gene-sequencing techniques and computer analysis allowed them to demonstrate how granulocytes use noncoding DNA to regulate the activity of a group of genes that determines the cells' shape and function.

Based on a comprehensive analysis of the scientific evidence, as required by the Federal Food, Drug and Cosmetic Act (FD&C Act), the FDA has determined that AquAdvantage Salmon meets the statutory requirements for safety and effectiveness under the FD&C Act. The salmon are safe to eat, the introduced DNA is safe for the fish itself, and the salmon meet the sponsor's claim about faster growth. Because the sponsor has met these requirements, the FDA must approve the application. The FDA has also analyzed the potential environmental impact that an approval of the AquAdvantage Salmon application would have on the quality of the human environment in the United States and has issued its final Environmental Assessment and Finding of No Significant Impact.

In a stunning discovery that overturns decades of textbook teaching, researchers have determined that the brain is directly connected to the immune system by vessels previously thought not to exist.

The short film opens with two questions: "So what determines how many species live in a given place? Or how many individuals of the species can live somewhere?" The research that provided answers to these questions was set in motion by key experiments by ecologists Robert Paine and James Estes. Robert Paine's starfish exclusion experiments on the coast of Washington state showed that removing starfish from this marine ecosystem has a big impact on the population sizes of other species, establishing the starfish as a keystone species. James Estes and colleague John Palmisano discovered that the kelp forest ecosystems of the North Pacific are regulated by the presence or absence of sea otters, which feed on sea urchins that consume kelp. These direct and indirect effects of sea otters on other species describe a trophic cascade. These early studies were the inspiration for hundreds of investigations on other keystone species and trophic cascades, as well as ongoing studies into the regulation of population sizes and species numbers.

In this case, developed for an introductory genetics class, students meet a woman whose family has a history of colon cancer. Students create a pedigree based on information from the case and discuss what it means to be genetically predisposed to cancer. Using bioinformatics tools from the NCBI database, students identify and examine the mutation in the woman's APC gene that results in genetic predisposition to colon cancer. Finally, they investigate the biological function of the APC protein to understand why this mutation contributes to the development of cancer and determine whether APC is a proto-oncogene, tumor suppressor gene, or genome stability gene.

While genes determine most of our physical characteristics, the exact combination of genes we inherit, and thus our physical traits, is in part due to a process our chromosomes undergo, known as genetic recombination.

At the annual meeting of the American Association for Cancer Research in Washington DC this week, Wolchok and other researchers will report on their search for immunotherapy markers - ways to predict a patient's response to an immunotherapy or to show whether a given treatment is working. The work is hampered by the complexity of the immune system, but early results are converging on one point: that patients' own immune responses to cancer are crucial in determining outcomes.

In this lesson, students consider the case of a young doctor hired by a U.S. pharmaceutical company to test a new antibiotic in Nigeria during a meningitis epidemic. Students work through a Decision-Making Framework in small groups, in which they identify the ethical question, determine which facts are known or unknown, consider the values of different stakeholder groups, generate possible solutions, and then make and justify a decision about the case. 

Clinical trials are essential to providing the scientific data to determine whether new drugs, diagnostics or procedures are both safe and effective when used to diagnose and treat people.

When Jordan is diagnosed with brain cancer (glioblastoma multiform), his college plans are unexpectedly put on hold. This scenario is presented in order to teach students about gene regulation, as the efficacy of the drug Jordan receives for post-surgical treatment is dependent upon the activity level of a gene encoding a protein involved in DNA repair. This "flipped" case study requires students to prepare in advance outside of class by watching several short videos that have been selected to teach the basics of how cancer forms as well as the role of epigenetics in gene silencing. Inside of class, the case is delivered using progressive disclosure format in which students gradually receive additional information to answer a series of directed questions. To determine a treatment plan for Jordan, students analyze data from a research study involving patients treated for his specific type of cancer. The case is designed for advanced high school biology classes as well as lower-level undergraduate general biology courses for non-majors and majors.

Mr. Andersen shows you how to determine if a bond is nonpolar covalent, polar covalent, or ionc.

"I Heart Running" is a case study in which students diagnose the cause of exercise-induced tachycardia in an otherwise healthy, 27-year-old female. The patient, Sam, is a long-distance runner and realizes that her exercising heart rate reaches over 200 beats per minute. As the story of Sam's encounters with her physician develops, students are given results from multiple laboratory tests and detailed patient background information.  Students are guided through the material with a series of questions with the ultimate goal of determining the cause of the exercise-induced tachycardia that Sam experiences. The case study is based on actual laboratory results and was designed for students in an upper-level undergraduate Human Physiology course. In this activity students will learn about heart rate, cardiovascular physiology, and oxygen carrying capacity, and factors which influence these concepts, as they try to diagnose Sam.

If you were limited to choosing only three crops to sustainably farm in an arid, inhospitable environment, what would they be and how would you decide? This interrupted case study places students in the role of a proposed self-sufficient Martian colony that requires an optimized profile of food crops. After students form small groups, they discuss the factors that affect sustainability of a food supply, determine criteria for selection of crops to grow, and rank crops using these criteria. Lists of criteria and of foodstuffs are provided, but the case can easily be transformed into a problem-based learning (PBL) case by having students research and generate their own lists. The case includes questions that walk students through the selection process and require them to explain why they chose their criteria and how those criteria apply to their chosen foods. The case is designed for undergraduate students at the introductory level in courses in astronomy/astrobiology, food science/nutrition, agricultural engineering, or any discipline where sustainability is a key theme.

Now, University of Missouri researchers have determined that a compound found in green tea, and voluntary exercise, slows the progression of the disease in mice and may reverse its effects. Further study of the commonly found extract could lead to advancements in the treatment and prevention of Alzheimer's disease in humans.

3:16 video To track commercial fishing activity around the world, SkyTruth, a small nonprofit based in Shepherdstown, West Virginia, has recently launched Global Fishing Watch in partnership with Google and Oceana. This prototype tool analyzes a satellite-collected feed of tracking data from ships' automatic identification systems-which vessels use to communicate their location to one another-to map movement over time and automatically determine which ships are engaged in fishing activity. Each vessel is pinpointed on a map outlining fishing laws around the globe. This map will be publicly available on theWeb, allowing anyone with an Internet connection to act as a watchdog and see when and where commercial fishing activity is occurring.

Through this method, the researchers were able to identify that the frizzled-6 gene was expressed around eight times more in tumor-forming cell lines. The specific cascade initiated by frizzled-6 and how it affects the development of cancerous cells has yet to be determined. The overexpression of frizzled-6 suggests that the protein either forms tumor cells directly or is an indirect result of other mutated pathways.

This interrupted case study explores the role of cytoskeletal structures on human health, specifically on respiratory function, sperm motility, and female fertility. It follows the story of a couple struggling to conceive a child and the doctors working to help them. Students are presented with clinical histories, narrative elements, documentary-style videos, and microscopic evidence in order to determine the cause of the couple's infertility. Along the way, they learn about the three types of cytoskeletal elements and the roles these play in cellular biology and human physiology. The use of videos makes it suitable for the "flipped classroom," allowing students to prepare outside the classroom for the case study, which they then complete in class. An original video by the author on the structure and function of microtubules, microfilaments, and intermediate filaments is included. The case was developed for an introductory level general biology course and could be delivered during a unit on the cell structure and function. The case could also be used in a cell biology course.

Existing mouse models of lethal Ebola virus infection do not reproduce hallmark symptoms of Ebola hemorrhagic fever, neither delayed blood coagulation and disseminated intravascular coagulation, nor death from shock, thus restricting pathogenesis studies to non-human primates. Here we show that mice from the Collaborative Cross exhibit distinct disease phenotypes following mouse-adapted Ebola virus infection. Phenotypes range from complete resistance to lethal disease to severe hemorrhagic fever characterized by prolonged coagulation times and 100% mortality. Inflammatory signaling was associated with vascular permeability and endothelial activation, and resistance to lethal infection arose by induction of lymphocyte differentiation and cellular adhesion, likely mediated by the susceptibility allele Tek. These data indicate that genetic background determines susceptibility to Ebola hemorrhagic fever.

This case study is used to teach undergraduate students about hydraulic fracturing (hydrofracking), a controversial method for extracting methane from shale. The controversy arises from claims that chemicals used in the fracking process and the methane itself find their way into drinking water and are also sometimes found at dangerous levels in the air. The case study begins in a college chemistry class where a student inquires about a news item he saw about residents setting their tap water on fire. The instructor uses this as an opportunity for the students to research hydrofracking and natural gas, and she then integrate these topics into their present study of isotopes. The class first examines what isotopes are by using a guided inquiry based activity. The students then learn how mass spectrometry, which uses the principles just learned about isotopes, is employed to determine the source of methane in contaminated wells. This case study is designed for freshman chemistry students and students in environmental studies.

In a paper this week in Science, Vogelstein and Cristian Tomasetti, who joined the biostatistics department at Hopkins in 2013, put forth a mathematical formula to explain the genesis of cancer. Here's how it works: Take the number of cells in an organ, identify what percentage of them are long-lived stem cells, and determine how many times the stem cells divide. With every division, there's a risk of a cancer-causing mutation in a daughter cell. Thus, Tomasetti and Vogelstein reasoned, the tissues that host the greatest number of stem cell divisions are those most vulnerable to cancer. When Tomasetti crunched the numbers and compared them with actual cancer statistics, he concluded that this theory explained two-thirds of all cancers.