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This case study presents the fictional tale of two neighboring towns that have recently experienced a growth boom and are now suffering the environmental consequences. The case provides an opportunity to explore a wide variety of anthropogenic causes of natural capital degradation. Students are assigned the role of scientists working for the regional Department of Environmental Resources Management, and it is their job to discover the underlying causes for a wide variety of citizen complaints and to suggest reasonable and cost effective solutions. The case may be assigned as a recap activity after teaching a unit on natural capital degradation. The case includes a PowerPoint presentation as well as three lab activities that are included in the teaching notes. The case would be appropriate for high school or lower level undergraduate ecology or environmental science courses.

A decade-old technique that allows researchers to control brain function in lab animals could partially restore sight to the blind. In a trial sponsored by RetroSense Therapeutics, a startup company in Ann Arbor, Michigan, doctors will inject a harmless virus loaded with DNA from photoreceptive algae into the eyes of 15 patients suffering from retinitis pigmentosa. The experimental procedure represents the first human test of optogenetics, which is a technique that genetically modifies neurons to make them responsive to light. Doctors from the Retina Foundation of the Southwest will perform the procedure, and attempt to transfer the job duties of photoreceptor cells to different cells in the eye to restore sight.

View slides and interactive graphics from the Earth Lab: Degrees of Change exhibit at the Marian Koshland Science Museum of the National Academy of Sciences.

Imagine something small enough to float on a particle of dust that holds the keys to understanding cancer, virology, and genetics. Luckily for us, such a thing exists in the form of trillions upon trillions of human, lab-grown cells called HeLa. But where did we get these cells? Robin Bulleri tells the story of Henrietta Lacks, a woman whose DNA led to countless cures, patents, and discoveries.

The team, led by senior authors Qi Zhou and Xiao-Yang Zhao, both from the Institute of Zoology at the Chinese Academy of Sciences, took embryonic stem cells from mice and treated them to a series of carefully worked out steps that included first exposing the stem cells to testicular cells in newly born male mice. The scientists then recreated the chemical environment that sperm cells need to grow, including early development factors and sex hormones including testosterone, follicle stimulating hormone and a growth factor from the pituitary gland.

Focusing on this species of fruit fly, he and the other researchers in the lab of molecular biologist Sean B. Carroll, had made a prolonged assault on one of the key questions in evolutionary biology: how nature endows creatures with their colorful patterns, from a leopard's dark spots to a butterfly's bold swirls. In different species the patterns serve to attract mates, provide camouflage or provide other advantages in the struggle to survive. But what causes the colors to fall so precisely into place?

Tweaking the human genome with current and future gene-editing tools could lead to sophisticated treatments and prevention strategies for disease. The promise of those applications is reason enough to move forward with such work in the lab and clinic, albeit cautiously, the dozen scientists and bioethicists who organized the International Summit on Human Gene Editing said today after three days of deliberation and presentations in Washington, D.C.

If the lab technique works in the field, it could offer a new way of stopping the biting insects from spreading malaria to humans, they say. The scientists put a new "resistance" gene into the mosquito's own DNA, using a gene editing method called Crispr. And when the GM mosquitoes mated - their offspring inherited the same resistance, PNAS journal reports. In theory, if these mosquitoes bite people, they should not be able to pass on the parasite that causes malaria.

WASHINGTON - The National Institutes of Health is sending its last remaining research chimpanzees into retirement - as soon as a federal sanctuary has room for them. The government already had declared that the use of humans' closest relative as a test subject was coming to an end. In 2013, the NIH said it would retire most of the several hundred government-owned chimps still living at research laboratories. But it set aside 50 animals to be on standby just in case they still were needed for a public-health emergency or some other extreme situation. Wednesday, the agency said those chimps' lab days are over, too.

Panobinostat is a new type of drug that works by blocking an enzyme responsible for modifying DNA at the epigenetic level. Epigenetics refers to chemical marks on DNA itself or on the protein "spools" called histones that package DNA. These marks influence the activity of genes without changing the underlying sequence, essentially acting as volume knobs for genes. Earlier genomic studies showed that about 80 percent of DIPG tumors carry a mutation that alters a histone protein, resulting in changes to the way DNA is packaged and tagged with those chemical marks. This faulty epigenetic regulation results in activation of growth-promoting genes that should have been turned off, and shutdown of others that should have acted as brakes to cell multiplication. Cancer is the result. Panobinostat appears to work by restoring proper functioning of the cells' chemical tagging system.

This interrupted case study for the flipped classroom introduces the human microbiome from the perspective of one of its occupants, Heidi Helicobacter (Helicobacter pylori).  Heidi lives in the gut of Kristen, a college student, and discusses her fellow microbial inhabitants, functions of these various microbes, and alludes to factors that can disrupt the healthy human microbiome. Students prepare for class by viewing several brief videos and then discuss in class whether Kristen should undergo a fecal microbiota transplant to treat her Clostridium difficile infection.  A lab component has students model, using colored beads, how antibiotics can act as a selective agent for drug-resistant microbes such as C. difficile. The case concludes with Kristen about to give birth to a new baby several years later.  Students listen in as Kristen's microbes discuss the formation of the new baby's microbiome. The case has been used successfully in a general biology class and could easily be adapted for a microbiology, human physiology, ecology, or evolution course.

Teachers: the files here are only a sampling of possible virtual lab assignments. You are welcome to use the simulations however you see fit for your classroom and students.

activities complementing 15 minute video about evolution and natural selection in stickleback fishes

Virutal microscope simuation

Regents prep resources

transgenic expression of spider silk in milk

In a north London hospital, scientists are growing noses, ears and blood vessels in the laboratory in a bold attempt to make body parts using stem cells.