Prolonged exposure to hyperoxia results in acute lung injury (ALI), accompanied by a significant elevation in the levels of proinflammatory cytokines and leukocyte infiltration in the lungs. However, the mechanisms underlying hyperoxia-induced proinflammatory ALI remain to be elucidated. In this study, we investigated the role of the proinflammatory cytokine high mobility group box protein 1 (HMGB1) in hyperoxic inflammatory lung injury, using an adult mouse model. The exposure of C57BL/6 mice to ≥99% O2 (hyperoxia) significantly increased the accumulation of HMGB1 in the bronchoalveolar lavage fluids (BALF) prior to the onset of severe inflammatory lung injury. In the airways of hyperoxic mice, HMGB1 was hyperacetylated and existed in various redox forms. Intratracheal administration of recombinant HMGB1 (rHMGB1) caused a significant increase in leukocyte infiltration into the lungs compared to animal treated with a non-specific peptide. Neutralizing anti-HMGB1 antibodies, administrated before hyperoxia significantly attenuated pulmonary edema and inflammatory responses, as indicated by decreased total protein content, wet/dry weight ratio, and numbers of leukocytes in the airways. This protection was also observed when HMGB1 inhibitors were administered after the onset of the hyperoxic exposure. The aliphatic antioxidant, ethyl pyruvate (EP), inhibited HMGB1 secretion from hyperoxic macrophages and attenuated hyperoxic lung injury. Overall, our data suggest that HMGB1 plays a critical role in mediating hyperoxic ALI through the recruitment of leukocytes into the lungs. If these results can be translated to humans, they suggest that HMGB1 inhibitors provide treatment regimens for oxidative inflammatory lung injury in patients receiving hyperoxia through mechanical ventilation.

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Because Human Anatomy and Physiology (A&P), a gateway course for allied health majors, has high dropout rates nationally, it is challenging to find a successful pedagogical intervention. Reports on the effect of integration of flipped classrooms and whether it improves learning are contradictory for different disciplines. Thus many educators are reluctant to explore the value of flipped classrooms. Therefore, in the present study we compare incorporating flipped classroom and minimal class discussion (control group) with flipped classroom and active learning activities (experimental group) in A&P and their impacts on both students' exam performance and their satisfaction with the course. Assessments consisted of a survey of students' attitudes and a comparison of exam performance in experimental and control groups. Exam performance among the students in flipped-classroom and active learning activities improved significantly relative to the control group [Mean ± SD: (76.93±18.33 vs 67.8±18.81), p<0.001. Student attitude, in which students rated the efficiency of pedagogical learning on a five-point Likert scale, was positive: the majority of students strongly preferred active-learning activities that were incorporated in the flipped-classroom. Students indicated that these activities helped them learn better and to connect the materials to the goals of their future careers (73.88% and 79.77% respectively). Therefore, we conclude that flipped classroom coupled with active learning strategies can improve students' performance and attitude in the introductory A&P course.

Embryonic development and differentiation to adult form depends on orchestration of cell division and death. In embryos, programmed death sculpts form, opens lumens, separates or splits tissue layers, allows tissue layers to fuse and removes vestigial organs. Both the central nervous and immune system overproduce cells and destroy those that do not form successful synapses or produce unusable antibodies. Cell death is first seen in mammalian embryos when the blastocyst expands, but elsewhere, the first deaths are not seen before the maternal‐zygotic transition. Abnormal timing, amount or localisation of cell death leads to abnormalities or death of embryos. Several signalling pathways trigger cell death. Usually the signals activate caspases (first discovered in embryonic cell death in nematodes) and lead to apoptosis, although apoptosis is not the only form of cell death. The signalling mechanisms that control cell death in embryos are not well understood, but should be if we hope to understand normal and teratological development. Key Concepts: Cell death can be seen in both embryonic development and normal growth of adult tissue. The embryonic cell deaths are highly programmed in that they are predictable in location, time and amount. In the simplest instances, such as in nematodes, control of cell death is under direct control of a small number of genes. Most but not all of the embryonic deaths are apoptotic. Embryonic cell to sculpt the embryo and define the boundaries of tissues and organs. In the central nervous system and the immune system, overgrowth (production of excessive cells) and subsequent pruning by cell death generate the high specificity that characterises these systems. Deregulation of apoptosis can produce many embryonic abnormalities and teratologies and, later in life, produces cancers, autoimmune disease or neurodegenerative disease. There are many means to study cell death, but only a few are directly applicable to the study of cell death in embryos. Nevertheless, further study is needed to understand the signalling mechanisms that decide the death of cells in specific locations and times. Learning more about cell death in embryos will help us to understand how it is controlled in adults.

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Undergraduate biology education has changed over the past decade, incorporating an iterative and evidence-based approach. Many educational assessments have confirmed the effectiveness of integrating authentic research and open-ended inquiry into introductory biology courses, demonstrating a significant positive impact on students' learning and attitude towards STEM majors. Despite these findings, only a handful of Biology instructors in 2year colleges adopt this approach, and when adopted, most activities constitute a small fraction of these courses. Finding a feasible, sustainable, semester-long, and cost-effective strategy to incorporate authentic research in the curriculum which promotes integrated understanding of science and addresses socio-scientific issues, is a big challenge for both instructors and administrators at 2-year colleges. Here we present a unique model incorporating a semester-long authentic research-based set of laboratories in introductory Biology through which students investigate the water quality in areas close to their communities. Our approach is fully aligned with all five core components of an effective Course-based Undergraduate Research Experience according to CUREnet. The laboratories were developed to be fully incorporated into the teaching curriculum. Each laboratory was designed to ensure students acquire the knowledge and skills set out in the course syllabus through a process of discovery designed to promote students' engagement.