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 In one of the first successful attempts at genetically engineering mosquitoes, HHMI researchers have altered the way the insects respond to odors, including the smell of humans and the insect repellant DEET. The research not only demonstrates that mosquitoes can be genetically altered using the latest research techniques, but paves the way to understanding why the insect is so attracted to humans, and how to block that attraction. "The time has come now to do genetics in these important disease-vector insects.

Sure, we know insufficient serotonin levels get a bad rap when it comes to depression, but that's like blaming one person in a full-scale riot. Depression isn't caused by only one factor. In fact, study co-author Elyse Aurbach says we're probably not getting to the core of why people are depressed because "the brain is immensely complex." In this study, the research team conducted eight experiments (four on animal brains, four on brains of the deceased human kind) of varying sample sizes - from 20 to 90 brains in each - and found that the brains of deceased humans who'd been depressed had increased levels of hippocampal FGF9 and that live animals with increased FGF9 levels demonstrated depressive, anxious behavior. "This is not just a correlation," study leader Huda Akil of the University of Michigan says. Less really may be more, at least when it comes to FGF9.

Hyper-IgM syndrome is an X-linked genetic disorder more commonly affecting males than females. It is caused by the lack of heavy chain class-switching from IgM to other isotypes. Patients with hyper-IgM syndrome are susceptible to a variety of infections as demonstrated in this medical case study. Students are presented patient information, symptoms and a diagnosis that must be interpreted. The case was written for use with the team-based learning (TBL) format involving groups of 4-5 students per group, but it could also be completed as an individual project. The case is targeted to premedical/allied health advanced students and is appropriate for any immunology course at the undergraduate or graduate level in a biomedical science program, or health-related professional courses such as advanced physiology, pathophysiology, microbiology, or histology and cytology.

October 16 is World Anesthesia Day, celebrating the 170th anniversary of the first successful demonstration of surgical anesthesia. Prior to then, surgery was really unpleasant, to put it mildly -- surgeons turned to alcohol, narcotics and even smacking their patients on the head to induce unconsciousness. Fortunately, anesthesia now allows tens of thousands patients every day to avoid the pain and memories of their procedures. But how does anesthesia work? This week, Reactions looks at scientists' current understanding of what happens when you go under.

Ever wonder how your brain processes information? These brain tricks and illusions help to demonstrate the two main systems of Fast and Slow Thinking in your brain.

Although Hardy-Weinberg equilibrium is a fundamental part of introductory biology classes, students often have difficulty understanding its implications. This interrupted case study places students in the role of small teams who are conducting preliminary research into the impact of roads on the population structure of timber rattlesnakes in order to apply for a grant for further research. Research groups consisting of 3-4 students work through a series of questions allowing them to use HWE principles to discover for themselves how deviations from HWE can have implications for conservation biology. Periodic interruptions with help sheets (see Supplemental Materials) allow teachers to maintain an active role in the students' progress, while also demonstrating the collaborative nature of scientific research. Ultimately students formulate formal emails summarizing and interpreting their findings in order to "apply" for the grant. The case is designed for undergraduate students in introductory biology or in lower-level population genetics/conservation courses where connecting basic genetic principles to ecology and sustainability is key.

Microsoft scientists have demonstrated that by analyzing large samples of search engine queries they may in some cases be able to identify internet users who are suffering from pancreatic cancer, even before they have received a diagnosis of the disease.

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.

Microsoft scientists have demonstrated that by analyzing large samples of search engine queries they may in some cases be able to identify internet users who are suffering from pancreatic cancer, even before they have received a diagnosis of the disease.

This dilemma/decision case study is intended to demonstrate how knowledge of signal transduction pathways can be applied to the pharmaceutical industry and within a medical setting. The case scenario revolves around a physician scientist's analysis of a chronic myelogenous leukemia (CML) patient's resistance to the cancer drug Gleevec® (imatinib). Students explore the molecular targets of drugs that inhibit cell signaling, while considering the best course of treatment for the medical patient. Written for an undergraduate sophomore level cell biology course, the case is also suitable for general biology, genetics, molecular biology, pharmacology, and cancer biology.

All introductory biology textbooks, and many sophomore-level genetics textbooks as well, describe several classic experiments in molecular biology. This interrupted case study takes students through two of these classic experiments, namely, those by Griffith and Avery, McCarty and MacLeod that showed DNA to be the genetic material in Streptococcus pneumoniae, and the experiment by Meselson and Stahl that demonstrated DNA replication to be semiconservative. Engaging students with the experiments in a more exploratory manner can reinforce the nature of scientific discovery and the logic behind these findings. The case, which has been formatted as two separate exercises that can be used independently, was developed for use in introductory biology classes for biology majors. The material is accessible enough to also be useful for non-majors college biology or high school AP biology students.

A team of Indian biologists has demonstrated that a key component of the water buffalo genome can be manipulated to produce foreign proteins in the buffalo's milk (J. Biotechnol. 2015, DOI:10.1016/j.jbiotec.2015.02.001). The findings suggest the possibility of modifying the genetic material of water buffalo-that is, creating transgenic buffalo-to produce protein drugs, says team member Subeer S. Majumdar, of the National Institute of Immunology, in New Delhi.

Scientists and clinicians have demonstrated that a neuroprotectant drug protects the human brain against the damaging effects of stroke. In patients who had ruptured brain aneurysm, which comprise a population of patients at very high risk of neurological damage, those treated with Tat-NR2B9c all had good neurological outcomes, whereas only 68% of those treated with placebo had good outcomes.

The Tuskegee Syphilis Study was initiated because known treatments for syphilis, in 1932, had shown little demonstrated effect, in addition to being toxic and dangerous. The dependent variable in the Tuskegee Experiment (the knowledge researchers wanted), was whether persons with syphilis were, in fact, better off without the treatment.

Many of these labs allow students to test multiple variables. Caution: the journal and data entry sections of the simulations do not work, so you probably will want to arrange for students to write these on their own pages. Many of these labs are useful to substitute for activities in the class that are too costly, dangerous, or time consuming. I have assigned grades to some that I've explored in detail. Grades are based on interactivity, useability, and overall value of the exploration. Many of these can be used as simple class demonstrations, whereas others are more useful for having students explore and change variables.

Origins of Life Abiogenesis article in Wikipedia. The Origin of Life - Abiogenesis, a youtube video produced by Chuck Kopec.  A Simpler Origin for Life, an article by Robert Shapiro in Scientific American. The Miller-Urey Experiment article in Wikipedia. RNA and the RNA World Exploring the New RNA World, an essay by Thomas Cech published on the Nobel Prize website. RNA Video Clips from the HHMI website that include demonstrations of catalysis and interviews with Thomas Cech. A World Apart, an HHMI article about RNA World reseearch and the role of RNAs in medicine.  RNA World article in Wikipedia. Protocells The Emergence of Cells During the Origin of Life, an essay by Irene Chen published in Science.  What Came Before DNA? an article published in Discover featuring Jack Szostak and Steven Benner.  The Szostak Lab Astrobiology The National Astrobiology Institute, established by NASA to study life in the universe.  The SETI Institute, studying the origins, nature and prevalence of life in the universe.  Astrobiology: The Search for Life, a website hosted by the Exploratorium.

In their study of the medium ground finches, evolutionary biologists Peter and Rosemary Grant were able to track the evolution of beak size twice in an amazingly short period of time due to two major droughts that occurred in the 1970s and 1980s. This activity simulates the food availability during these droughts and demonstrates how rapidly natural selection can act when the environment changes. Students use two different types of tools to represent different beak types to see which is best adapted to collect and "eat" seeds of different sizes. Students collect and analyze data and draw conclusions about traits that offer a selective advantage under different environmental conditions. They have the option of using an Excel spreadsheet to calculate different descriptive statistics and interpret graphs.

This is an animated demonstration of osmosis, specifically isotonic, hypotonic and hypertonic solutions. More educational videos can be found at: http://www.mcsdpodcast.net

Research leading to almost every Nobel Prize in Medicine awarded since 1901 was dependent on data from animal models.  This fact dramatically demonstrates the important contribution animal models in biomedical research make to both international and American medical progress. In fact, since 1979, every Nobel Prize in Medicine awarded was dependent on data from animal models with the exception of the 1983 Prize awarded to Dr. Barbara McClintock for her work in plant genetics.

This clicker case addresses several important concepts related to evolution. First, it explores artificial selection and selective breeding. Charles Darwin used artificial selection as an example to support his Theory of Evolution by Natural Selection. Belyaev's Fox-Farm experiment is used as an example of a study that used selective breeding as the primary experimental procedure to investigate changes in a lineage. Second, it addresses an interesting observation made by Charles Darwin in The Origin of Species in which he noted how domesticated species also show interesting traits such as drooping ears which seem to be common in domesticated species. The "Farm-Fox Experiment" not only demonstrates how a research team can thoroughly investigate an intriguing question, but also serves as a classic example of elegant experimental design. Designed for use in a large introductory-level biology class, this case study would also be appropriate for smaller classes as well as for upper-level evolution courses.