Aquatic models of human ciliary diseases

Cilia are microtubule‐based structures that either transmit information into the cell or move fluid outside of the cell. There are many human diseases that arise from malfunctioning cilia. Although mammalian models provide vital insights into the underlying pathology of these diseases, aquatic organisms such as Xenopus and zebrafish provide valuable tools to help screen and dissect out the underlying causes of these diseases. In this review we focus on recent studies that identify or describe different types of human ciliopathies and outline how aquatic organisms have aided our understanding of these diseases.     

Electron cryotomography of ESCRT assemblies and dividing Sulfolobus cells suggests that spiraling filaments are involved in membrane scission

The endosomal-sorting complex required for transport (ESCRT) is evolutionarily conserved from Archaea to eukaryotes. The complex drives membrane scission events in a range of processes, including cytokinesis in Metazoa and some Archaea. CdvA is the protein in Archaea that recruits ESCRT-III to the membrane. Using electron cryotomography (ECT), we find that CdvA polymerizes into helical filaments wrapped around liposomes. ESCRT-III proteins are responsible for the cinching of membranes and have been shown to assemble into helical tubes in vitro, but here we show that they also can form nested tubes and nested cones, which reveal surprisingly numerous and versatile contacts. To observe the ESCRT–CdvA complex in a physiological context, we used ECT to image the archaeon Sulfolobus acidocaldarius and observed a distinct protein belt at the leading edge of constriction furrows in dividing cells. The known dimensions of ESCRT-III proteins constrain their possible orientations within each of these structures and point to the involvement of spiraling filaments in membrane scission.     

The VMO:VL activation ratio while squatting with hip adduction is influenced by the choice of recording electrode

Concomitant hip adduction during squatting has long been advocated as a rehabilitative method to preferentially activate the VMO in persons with patellofemoral pain. This practice however has been based on research using surface electrodes which are prone to crosstalk from neighboring muscles (i.e., adductor magnus). This study sought to determine whether activation levels of the VMO relative to the VL while squatting with hip adduction would differ based on the choice of recording electrode. Ten healthy subjects performed a maneuver with hip adduction and without hip adduction. The mean VMO and VL activation levels were recorded simultaneously with surface and indwelling fine-wire electrodes. For both recording electrodes, the VMO and VL activity increased significantly with the addition of hip adduction (p < 0.05). However, the increase in VMO activation was more pronounced with surface electrodes, resulting in a significantly higher VMO:VL ratio with the incorporation of hip adduction compared to without hip adduction (p < 0.05). No difference in the VMO:VL ratio was observed between the two squat conditions for the fine-wire electrodes (p > 0.05). Our findings suggest that the VMO:VL activation ratio when squatting with hip adduction is influenced by electrode choice.     

Metal Craft Problems

Although goals change and reflect the issues of the time, two primary goals of education in a democracy have remained constant over time. The first goal is to educate for vocational competence and the second is to produce caring, intelligent, and wise citizens. Articulating the connection of design education concepts to the economy and social responsibility is beneficial in educating K–12 students. This article illustrates the ways in which design education fosters the skills needed in the global twenty-first century to help students make a better life for themselves and their community and improve the world. I articulate ways to incorporate design as an essential component into a comprehensive visual arts program.     

Using Fecal Hormonal and Behavioral Analyses to Evaluate the Introduction of Two Sable Antelope at Lincoln Park Zoo

Introductions of sable antelope (Hippotragus niger) can be difficult due to the potential ensuing aggression compounded by their large horns. The goal was to use hormonal assays and behavioral analyses to evaluate the success of an introduction of 2 adult females at Lincoln Park Zoo. The objectives were to (a) document behavioral and hormonal changes in 2 female sable antelope during the introduction, (b) compare fecal glucocorticoid metabolites (FGM) in each individual during the introduction stages, (c) measure fecal androgen metabolites (FAM) during introduction and compare with dominance rank and observed aggression, and (d) monitor estrous cycle synchronization. Results demonstrate that FGM were higher before than during and after the introduction. Behavioral observations indicated limited aggression between females, although the keeper survey results revealed that the new female was more dominant and had higher mean FGM and FAM than the resident. Both sable antelope were reproductively active throughout the year. Results indicate that fecal hormone analysis can provide zoo management with valuable information to minimize the risk of aggression, injury, and stress during introductions of nonhuman animals.     

Association of CAT polymorphisms with catalase activity and exposure to environmental oxidative stimuli

We tested the hypotheses that catalase activity is modified by CAT single nucleotide polymorphisms (SNPs) (-262;-844), and by their interactions with oxidant exposures (coal dusts, smoking), lymphotoxin alpha (LTA, NcoI) and tumor necrosis factor (TNF, -308) in 196 miners. Erythrocyte catalase, superoxide dismutase, and glutathione peroxidase activities were measured. The CAT -262 SNP was related to lower catalase activity (104, 87 and 72 k/g hemoglobin for CC, CT and TT, respectively, p < 0.0001). Regardless of CAT SNPs, the LTA NcoI but not the TNF-308 SNP was associated with catalase activity (p = 0.04 and p = 0.8). CAT -262 T carriers were less frequent in highly exposed miners (OR = 0.39 [0.20–0.78], p = 0.007). In CAT -262 T carriers only, catalase activity decreased with high dust exposure (p = 0.01). Haplotype analyses (combined CAT SNPs) confirm these results. Results show that CAT -262 and LTA NcoI SNPs, and interaction with coal dust exposure, influenced catalase activity.     

A Novel Method for the Preparation of Substrate-Free Cytochrome P-45011β

A new method for the removal of the stabilizing substrate, deoxycorticosterone, from adrenal cytochrome P-450_11β, has been developed. Dextran coated charcoal is used for the adsorption of the steroid and the adsorbed steroid is separated from the cytochrome P-450-preparation by low speed centrifugation. The substrate-free enzyme, obtained in this manner, has all the characteristic spectral properties of low-spin cytochrome P-450_11β, and may be converted to the high-spin form by the addition of deoxycorticosterone.

The dextran coated charcoal method has the following advantages over the previously used method of substrate removal. It does not require the addition of the cofactors for cytochrome P-450-dependant hydroxyla-tion of deoxycorticosterone, small amounts of enzyme may be prepared in a short time and the enzyme preparation is not diluted to any great extent during the process.     

Comparison of Trees and Grasses for Rhizoremediation of Petroleum Hydrocarbons

Rhizoremediation of petroleum contaminants is a phytoremediation process that depends on interactions among plants, microbes, and soils. Trees and grasses are commonly used for phytoremediation, with trees typically being chosen for remediation of BTEX while grasses are more commonly used for remediation of PAHs and total petroleum hydrocarbons. The objective of this review was to compare the effectiveness of trees and grasses for rhizoremediation of hydrocarbons and address the advantages of each vegetation type. Grasses were more heavily represented in the literature and therefore demonstrated a wider range of effectiveness. However, the greater biomass and depth of tree roots may have greater potential for promoting environmental conditions that can improve rhizoremediation, such as increased metabolizable organic carbon, oxygen, and water. Overall, we found little difference between grasses and trees with respect to average reduction of hydrocarbons for studies that compared planted treatments with a control. Additional detailed investigations into plant attributes that most influence hydrocarbon degradation rates should provide data needed to determine the potential for rhizoremediation with trees or grasses for a given site and identify which plant characteristics are most important.