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On September 15, the Washington University School of Medicine published a study in The American Journal of Psychiatry revealing that schizophrenia, commonly thought of as a single mental disorder, is actually a group of eight distinct afflictions. People with schizophrenia are typically diagnosed in their 20s, which is when symptoms (such as delusions and hallucinations) begin to manifest. The brain disorder affects about 1 percent of the population, and it is highly genetic: According to the NIH, having a relative diagnosed with schizophrenia increases one's chances of developing the disorder by 10 percent, while having an identical twin with the disorder raises the risk to 40 to 65 percent.

To treat problems from sore throats to acne, doctors expose kids early and often - and scientists have been finding links between antibiotic use and rising chronic illnesses. A new study in mice published in the journal Nature Microbiology finds a link between Type 1 diabetes and antibiotic use.

This case study uses a jigsaw activity to introduce students to four specific plant responses to climate change: elevational range shifts, phenology shifts, community shifts, and changes in biodiversity. Students become "experts" on one of these responses by reading an article (from Nature, Science, or American Journal of Botany; not included with the case) on their assigned topic and then sharing their expertise with others in class. In order to hone their understanding and increase retention on these topics, students then learn about plant communities found in a specific system-vernal pools or seasonal wetlands typical of Mediterranean climates (a PowerPoint presentation on this topic is included). Students accomplish several small group tasks to assess how different vernal pool plant communities have responded to fluctuations in annual weather patterns and predict how these communities may respond to greater weather variability resulting from future climatic change. This case was written for mid- to upper-level ecology, plant ecology, botany, or environmental studies courses. The material covered may also be suitable for classes examining the role of weather variability/climate change in relation to plants.

The human large intestine (colon), in healthy individuals, has extremely low oxygen concentrations, and over 90% of its microbiota are strict anaerobes. Researchers taking metagenomic fecal microbiota surveys of adult Europeans could assign about 0.8% of the genes in their dataset to archaea [9], and similar numbers (0.2%-0.3%) were reported for Amerindians and Malwaians [10], while North Americans had much lower fractions (<0.05%).

This case study synthesizes students' knowledge of the central dogma and cell structure by examining a rare health disorder in order to understand protein targeting and its medical consequences. Students first identify the molecular alteration in affected members of a family with renal Fanconi syndrome as reported in the New England Journal of Medicine (2014). Students then use an online bioinformatics tool to analyze the wildtype and mutant proteins and examine their subcellular localization. Finally, students use this information to explain the symptoms of affected family members. The case is delivered with a PowerPoint presentation that includes a selection of brainstorming prompts and "clicker questions." Students complete a worksheet (included in the teaching notes) before class, making the activity suitable for a flipped classroom. A second worksheet (also included in the teaching notes) is completed during class. The case is written for an introductory biology course for majors, but could also be used as a unit capstone in a non-majors human biology course; the case is also scalable to upper division courses in physiology that specifically explore kidney function.

"This case study introduces students to Duchenne muscular dystrophy (DMD) and its underlying genetics, cell biology, and some of the associated biochemical pathways.  DMD is an X-linked disorder characterized by progressive muscle weakness and wasting due to the absence of a protein called dystrophin, which in turn causes degeneration of skeletal and cardiac muscle. There is currently no established cure for this disease.  The case follows the progress of "Casey," an undergraduate student who has just declared her biology major and is interested in expanding her scientific understanding of the different fields of biology. The case is organized in three parts: genetics, cell biology, and biochemistry, each exploring DMD through its unique lens. Throughout the case, Casey is presented with multiple outlets of information, including class lectures, direct e-mail interaction with a professor, scientific journals and websites, from which she (and any student engaged with the case) gathers knowledge about DMD."

For a study published Tuesday in the journal Nature Communications, Partridge and other researchers from Philadelphia suspended premature lambs, a close animal model for human fetuses, in a liquid-filled, artificial womb, allowing them to further develop for four weeks-longer than in past similar attempts.

This case study describes the daily osmotic struggle for survival faced by hummingbirds. The narrative is written from the viewpoint of a human observer who sees an Anna's hummingbird feeding on flowers outside of her window.  She notices that the birds mostly feed early in the morning and again in the evening at dusk; midday encounters are rare.  The case raises questions about floral nectar production, how this correlates to feeding bouts, and how this in turn correlates to the daily osmotic challenges faced by these nectarivorous birds and their allies (sunbirds). Students will learn about renal adaptations for survival and how they operate. Finally, since hummingbirds have a high metabolic rate and cannot feed overnight they undergo torpor during this time, an energy saving physiologic state.  Students read journal articles to answer case questions, which should lead them to a better understanding of the related physiological processes of osmoregulation, metabolic rate and torpor.

This case study centers on symbiotic relationships between insects and bacteria using Drosophila melanogaster, the common fruit fly, and the recently discovered bacterial species Sodalis praecaptivus. Until recently, the only known Sodalis species of bacteria were symbiotically associated with several different species of insects. However, free-living non-symbiont Sodalis species are being tested in several different insect species to determine if they can transition into symbiotic relationships. A pre-class assignment (see Supplemental Materials) directs students to read an open access research journal article providing a comprehensive review of S. praecaptivus and describing an experimental weevil model that parallels that of the fruit fly. A PowerPoint presentation shown in class (see Supplemental Materials) provides further background before students work in small groups to complete the case study focusing on results from D. melanogaster and S. praecaptivus model experiments.  Although developed for a genetics course, this interrupted case is appropriate for an upper-level biology course. It can be completed within a 75-minute class meeting, or adapted for shorter time periods.

The activity begins with students observing different organisms or phenomena and developing questions based on their observations. They then sort their questions into those that can and cannot be answered using the methods of science. Students practice writing scientific questions, designing experiments to address scientific questions, developing questions that involve cause and effect, and understanding the importance of cause and effect questions in scientific research. At the end of the activity, students determine the research questions being asked from reading journal article titles and parts of a published paper or other reported results. Several possible extension activities are provided for continuing the investigation and research of phenomena.

Importance  Despite research showing no link between the measles-mumps-rubella (MMR) vaccine and autism spectrum disorders (ASD), beliefs that the vaccine causes autism persist, leading to lower vaccination levels. Parents who already have a child with ASD may be especially wary of vaccinations. Objective  To report ASD occurrence by MMR vaccine status in a large sample of US children who have older siblings with and without ASD.

From the following article: The velocity of climate change Scott R. Loarie, Philip B. Duffy, Healy Hamilton, Gregory P. Asner, Christopher B. Field & David D. Ackerly Nature 462, 1052-1055(24 December 2009) doi:10.1038/nature08649

The discovery of this genetic disorder, reported in two papers in the journal Cell, demonstrates the growing power of new tools to uncover the causes of diseases that previously stumped doctors.

High heritability points to a major role for inherited genetic variants in the aetiology of schizophrenia7, 8. Although risk variants range in frequency from common to extremely rare9, estimates10, 11 suggest half to a third of the genetic risk of schizophrenia is indexed by common alleles genotyped by current genome-wide association study (GWAS) arrays. Thus, GWAS is potentially an important tool for understanding the biological underpinnings of schizophrenia