Seeking a higher level of arts integration across the curriculum

To seek a higher level of arts integration across the education curriculum, I investigated designs of teaching through arts activities that would motivate educators to adopt the spirit of “aesthetic teaching.” Two different designs were tested, with the second as a continuation of the first. Each ascribes a different educational role to arts activities—in the first design the role of art is that of a teaching medium, while in the second its role is as a teaching approach to the taught subject. The study followed the steps of a “teaching design experiment.” The preschool teachers who constituted the sample used these activities with groups of kindergarteners. The analysis of the data was based on the reports of the teachers, which were examined for indicators of “aesthetic teaching.” The findings of this study suggest that there is a correlation between the educational role of the arts and the level of aesthetic orientation of educators in applying arts integration. Generally, the sample experienced the second design (in which the role of art is that of a teaching approach to the taught subject) as more of an aesthetic teaching situation than the first design (in which the role of art is that of a teaching medium).     

A cytokine super cyclone in COVID-19 patients with risk factors: the therapeutic potential of BCG immunization

The seventh human coronavirus SARS-CoV2 belongs to the cluster of extremely pathogenic coronaviruses including SARS-CoV and MERS-CoV, which can cause fatal lower respiratory tract infection. Likewise, SARS-CoV2 infection can be fatal as the disease advances to pneumonia, followed by acute respiratory distress syndrome (ARDS). The development of lethal clinical symptons is associated with an exaggerated production of inflammatory cytokines, referred to as the cytokine storm, is a consequence of a hyperactivated immune response aginst the infection. In this article, we discuss the pathogenic consequences of the cytokine storm and its relationship with COVID-19 associated risk factors. The increased pro-inflammatory immune status in patients with risk factors (diabetes, hypertension, cardiovascular disease, COPD) exacerbates the Cytokine-storm of COVID-19 into a ‘Cytokine Super Cyclone’. We also evaluate the antiviral immune responses provided by BCG vaccination and the potential role of ‘trained immunity’ in early protection against SARS-CoV2.     

History, genetic differentiation and conservation strategies for disjunct populations of Sibiraea species from Southeastern Europe and Asia

The genetic structure of Croatian Sibirea (Sibiraea croatica), a rare and endemic tertiary relic of Croatian and Herzegovinian flora, and its relationship with sibirea from Southern Russia and Southern Siberia (Sibiraea altaiensis) was studied using amplification, restriction and sequencing of the ITS region in genomic DNA and cpDNA and their comparisons with sequences of the Rosaceae species obtained from GenBank. The restriction analysis and separation in agarose gel showed no differences in length of the digested cpDNA between or within populations. Sequencing showed only minor variability between populations. Only a minor difference of 6 bp duplication in DNA amplified with ccmp 10-R and trnM primer pair was noticed in two geographically distinct populations. No differences in the restriction pattern for the ITS region in genomic rDNA indicates that all samples of sibirea belong to the same species since the ITS region was proven to be conserved within one taxonomic species. The minor differences that were␣obtained support the hypothesis that sibirea is an old tertiary relic that shows a minor variability, confirming previous preliminary results from comparisons of the Croatian and Altaic sibireas at the morphological level. Our data suggests that Croatian sibirea from the Balkan is a disjunct population identical to the Altaic species. Due to its disjunct occurrence in Southeastern Europe, the endemic status in the Dinarics, a relic that survived the glaciations, it deserves active conservation approaches through support of traditional use of high-mountain pastures for reducing natural reforestation of sibirea ancient sites.     

A Single-Domain Llama Antibody Potently Inhibits the Enzymatic Activity of Botulinum Neurotoxin by Binding to the Non-Catalytic α-Exosite Binding Region

Ingestion or inhalation of botulinum neurotoxin (BoNT) results in botulism, a severe and frequently fatal disease. Current treatments rely on antitoxins, which, while effective, cannot reverse symptoms once BoNT has entered the neuron. For treatments that can reverse intoxication, interest has focused on developing inhibitors of the enzymatic BoNT light chain (BoNT Lc). Such inhibitors typically mimic substrate and bind in or around the substrate cleavage pocket. To explore the full range of binding sites for serotype A light chain (BoNT/A Lc) inhibitors, we created a library of non-immune llama single-domain VHH (camelid heavy-chain variable region derived from heavy-chain-only antibody) antibodies displayed on the surface of the yeast Saccharomyces cerevisiae. Library selection on BoNT/A Lc yielded 15 yeast-displayed VHH with equilibrium dissociation constants (K_d) from 230 to 0.03 nM measured by flow cytometry. Eight of 15 VHH inhibited the cleavage of substrate SNAP25 (synaptosome-associated protein of 25,000 Da) by BoNT/A Lc. The most potent VHH (Aa1) had a solution K_d for BoNT/A Lc of 1.47 × 10^− 10 M and an IC₅₀ (50% inhibitory concentration) of 4.7 × 10^− 10 M and was resistant to heat denaturation and reducing conditions. To understand the mechanism by which Aa1 inhibited catalysis, we solved the X-ray crystal structure of the BoNT/A Lc-Aa1 VHH complex at 2.6 Å resolution. The structure reveals that the Aa1 VHH binds in the α-exosite of the BoNT/A Lc, far from the active site for catalysis. The study validates the utility of non-immune llama VHH libraries as a source of enzyme inhibitors and identifies the BoNT/A Lc α-exosite as a target for inhibitor development.     

Fractal analysis of vascular networks: Insights from morphogenesis

Considering their extremely complicated and hierarchical structure, a long standing question in vascular physio-pathology is how to characterize blood vessels patterns, including which parameters to use. Another question is how to define a pertinent taxonomy, with applications to normal development and to diagnosis and/or staging of diseases.To address these issues, fractal analysis has been applied by previous investigators to a large variety of healthy or pathologic vascular networks whose fractal dimensions have been sought. A review of the results obtained on healthy vascular networks first shows that no consensus has emerged about whether normal networks must be considered as fractals or not.Based on a review of previous theoretical work on vascular morphogenesis, we argue that these divergences are the signature of a two-step morphogenesis process, where vascular networks form via progressive penetration of arterial and venous quasi-fractal arborescences into a pre-existing homogeneous capillary mesh. Adopting this perspective, we study the multi-scale behavior of generic patterns (model structures constructed as the superposition of homogeneous meshes and quasi-fractal trees) and of healthy intracortical networks in order to determine the artifactual and true components of their multi-scale behavior. We demonstrate that, at least in the brain, healthy vascular structures are a superposition of two components: at low scale, a mesh-like capillary component which becomes homogeneous and space-filling over a cut-off length of order of its characteristic length; at larger scale, quasi-fractal branched (tree-like) structures. Such complex structures are consistent with all previous studies on the multi-scale behavior of vascular structures at different scales, resolving the apparent contradiction about their fractal nature.Consequences regarding the way fractal analysis of vascular networks should be conducted to provide meaningful results are presented. Finally, consequences for vascular morphogenesis or hemodynamics are discussed, as well as implications in case of pathological conditions, such as cancer.     

Taenia crassiceps: energetic and respiratory metabolism from cysticerci exposed to praziquantel and albendazole in vitro

Praziquantel prevents glucose uptake, influencing energy metabolism, while albendazole selectively inhibits the uptake of glucose, leading to glycogen storage depletion in the parasite. The objective of this study was to determine the concentrations of glucose and organic acids related to energy and respiratory metabolisms in in vitroTaenia crassiceps cysticerci in the initial, larval and final stages exposed to sub lethal dosages of anti-helminthic drugs. Spectrophotometric and chromatographic analysis were performed to detect glucose, lactate, oxaloacetate, citrate, malate, fumarate and succinate secreted/excreted by in vitro cysticerci with 0.03 and 0.06 μg/mL of praziquantel and 0.05 and 0.075 μg/mL of albendazole. The anti-helminthic drugs decreased the excretion of lactate and induced aerobic energy pathways. Concentrations of glucose remained unaltered confirming blockage of its uptake.     

Field-acclimated Gossypium hirsutum cultivars exhibit genotypic and seasonal differences in photosystem II thermostability

Previous investigations have demonstrated that photosystem II (PSII) thermostability acclimates to prior exposure to heat and drought, but contrasting results have been reported for cotton (Gossypium hirsutum). We hypothesized that PSII thermotolerance in G. hirsutum would acclimate to environmental conditions during the growing season and that there would be differences in PSII thermotolerance between commercially-available U.S. cultivars. To this end, three cotton cultivars were grown under dryland conditions in Tifton Georgia, and two under irrigated conditions in Marianna Arkansas. At Tifton, measurements included PSII thermotolerance (T₁₅, the temperature causing a 15% decline in maximum quantum yield), leaf temperatures, air temperatures, midday (1200 to 1400 h) leaf water potentials (Ψ_MD), leaf-air vapor pressure deficit (VPD), actual quantum yield (Φ_PSII) and electron transport rate through PSII (ETR) on three sample dates. At Marianna, T₁₅ was measured on two sample dates. Optimal air and leaf temperatures were observed on all sample dates in Tifton, but PSII thermotolerance increased with water deficit conditions (Ψ_MD = −3.1 MPa), and ETR was either unaffected or increased under water-stress. Additionally, T₁₅ for PHY 499 was ∼5 °C higher than for the other cultivars examined (DP 0912 and DP 1050). The Marianna site experienced more extreme high temperature conditions (20–30 days T_max ≥ 35 °C), and showed an increase in T₁₅ with higher average T_max. When average T₁₅ values for each location and sample date were plotted versus average daily T_max, strong, positive relationships (r² from .954 to .714) were observed between T_max and T₁₅. For all locations T₁₅ was substantially higher than actual field temperature conditions. We conclude that PSII thermostability in G. hirsutum acclimates to pre-existing environmental conditions; PSII is extremely tolerant to high temperature and water-deficit stress; and differences in PSII thermotolerance exist between commercially-available cultivars.     

盐胁迫下不同基因型冬小麦渗透及离子的毒害效应

以4种不同基因型冬小麦为试验材料,利用分根法研究了盐胁迫对小麦的渗透胁迫和离子毒害的效应。结果表明,在盐胁迫下,小麦既受渗透胁迫,也受盐离子胁迫。渗透胁迫效应比较快,大约在处理后1-2d内发生;离子毒害效应比较缓慢,大约需3-4d时间。在一半盐胁迫(200mmol/L NaCl)和一半非盐胁迫的分根条件下,小麦没有明显的渗透胁迫效应,小麦植株地上部Na⁺ 累积到毒性水平之前盐处理对小麦生长无抑制效应。小麦具有将Na⁺ 从盐胁迫一侧转移非盐一侧的能力,说明小麦吸收的Na⁺ 有一部分可以从地上部回流到根系中,回流率可达76%-89%。无水分胁迫(不加入PEG)的回流率大于水分胁迫(加入PEG)的回流率。不同基因型小麦在盐分吸收累积和回流,及渗透和离子胁迫的速度和程度等方面具有明显差异。NR 9405和小偃6号的Na⁺ 累积速度要少于陕229和RB 6;NR 9405根系排Na⁺ 能力强于陕229和RB 6。因此,NR 9405和小偃6号的耐盐性高于陕229和RB 6。