Citron kinase controls abscission through RhoA and anillin

The small GTPase RhoA plays a crucial role in the different stages of cytokinesis, including contractile ring formation, cleavage furrow ingression, and midbody abscission. Citron kinase (CIT-K), a protein required for cytokinesis and conserved from insects to mammals, is currently considered a cytokinesis-specific effector of active RhoA. In agreement with previous observations, we show here that, as in Drosophila cells, CIT-K is specifically required for abscission in mammalian cells. However, in contrast with the current view, we provide evidence that CIT-K is an upstream regulator rather than a downstream effector of RhoA during late cytokinesis. In addition, we show that CIT-K is capable of physically and functionally interacting with the actin-binding protein anillin. Active RhoA and anillin are displaced from the midbody in CIT-K-depleted cells, while only anillin, but not CIT-K, is affected if RhoA is inactivated in late cytokinesis. The overexpression of CIT-K and of anillin leads to abscission delay. However, the delay produced by CIT-K overexpression can be reversed by RhoA inactivation, while the delay produced by anillin overexpression is RhoA-independent. Altogether, these results indicate that CIT-K is a crucial abscission regulator that may promote midbody stability through active RhoA and anillin.     

Overexpression of the trichodiene synthase gene tri5 increases trichodermin production and antimicrobial activity in Trichoderma brevicompactum

Trichoderma brevicompactum produces trichodermin, a simple trichothecene-type toxin that shares the first steps of the sesquiterpene biosynthetic pathway with other phytotoxic trichothecenes from Fusarium spp. Trichodiene synthase catalyses the conversion of farnesyl pyrophosphate to trichodiene and it is encoded by the tri5 gene that was cloned and analysed functionally by homologous overexpression in T. brevicompactum. tri5 expression was up-regulated in media with glucose, H(2)O(2) or glycerol. tri5 repression was observed in cultures supplemented with the antioxidants ferulic acid and tyrosol. Acetone extracts of tri5-overexpressing transformants displayed higher antifungal activity than those from the wild-type. Chromatographic and spectroscopic analyses revealed that tri5 overexpression led to an increased production of trichodermin and tyrosol. Agar diffusion assays with these two purified metabolites from the tri5-overexpressing transformant T. brevicompactum Tb41tri5 showed that only trichodermin had antifungal activity against Saccharomyces cerevisiae, Kluyveromyces marxianus, Candida albicans, Candida glabrata, Candida tropicalis and Aspergillus fumigatus, in most cases such activity being higher than that observed for amphotericin B and hygromycin. Our results point to the significant role of tri5 in the production of trichodermin and in the antifungal activity of T. brevicompactum.     

Neurofeedback for Insomnia: A Pilot Study of <Emphasis Type="Italic">Z</Emphasis>-Score SMR and Individualized Protocols

Insomnia is an epidemic in the US. Neurofeedback (NFB) is a little used, psychophysiological treatment with demonstrated usefulness for treating insomnia. Our objective was to assess whether two distinct Z-Score NFB protocols, a modified sensorimotor (SMR) protocol and a sequential, quantitative EEG (sQEEG)-guided, individually designed (IND) protocol, would alleviate sleep and associated daytime dysfunctions of participants with insomnia. Both protocols used instantaneous Z scores to determine reward condition administered when awake. Twelve adults with insomnia, free of other mental and uncontrolled physical illnesses, were randomly assigned to the SMR or IND group. Eight completed this randomized, parallel group, single-blind study. Both groups received fifteen 20-min sessions of Z-Score NFB. Pre-post assessments included sQEEG, mental health, quality of life, and insomnia status. ANOVA yielded significant post-treatment improvement for the combined group on all primary insomnia scores: Insomnia Severity Index (ISI p < .005), Pittsburgh Sleep Quality Inventory (PSQI p < .0001), PSQI Sleep Efficiency (p < .007), and Quality of Life Inventory (p < .02). Binomial tests of baseline EEGs indicated a significant proportion of excessively high levels of Delta and Beta power (p < .001) which were lowered post-treatment (paired z-tests p < .001). Baseline EEGs showed excessive sleepiness and hyperarousal, which improved post-treatment. Both Z-Score NFB groups improved in sleep and daytime functioning. Post-treatment, all participants were normal sleepers. Because there were no significant differences in the findings between the two groups, our future large scale studies will utilize the less burdensome to administer Z-Score SMR protocol.     

Identification of major clonal complexes and toxin producing strains among Staphylococcus aureus associated with atopic dermatitis

Staphylococcus aureus promotes the onset and severity of atopic dermatitis (AD), which is exacerbated by superantigen toxins SEB and SEC. The genetic identity of these isolates, and their relationship to common hospital- or community-associated methicillin resistant S. aureus (HA-MRSA and CA-MRSA) has not been defined. We conducted spa typing, partial multi-locus sequence typing (MLST), and toxin profiling (seb, sec, lukS-PV) of S. aureus from 119 pediatric and 40 adult AD patients. MLST clonal complexes CC45, CC5, CC15, CC1, CC8 and CC30 accounted for 79% of isolates, representing the same major groups reported for nosocomial S. aureus in hospital intensive care units. The highest disease severity was associated with CC1, which was significantly greater relative to CC15 (p?=?0.017) or CC30 (p?=?0.040), but with no significant difference relative to CC45, CC5 or CC8. Although there were two few lukS-PV, seb or sec isolates to infer a role in disease severity, CC45 was identified as a source of SEC producing strains, and lukS-PVL was associated with a small number of CC5 pediatric isolates. CC1 harbored the only CA-MRSA that was identified, and was a source of isolates that expressed both seb and sec, and closely resembled the USA400 strain of CA-MRSA.     

The millipede family Polydesmidae in Taiwan, with descriptions of five new species (Polydesmida, Diplopoda)

Polydesmidae are represented in Taiwan by seven species in two genera. Neither of the genera is endemic to Taiwan, but six of the species are, including five new: Nipponesmus minorsp. n., Epanerchodus bispinosussp. n., Epanerchodus curtigonopussp. n., Epanerchodus flagellifersp. n. and Epanerchodus pinguissp. n. In addition, the diagnosis of the hitherto enigmatic genus Nipponesmus Chamberlin & Wang, 1953 is refined vis-à-vis the especially similar, Central Asian, Siberian and Eastern European genus Schizoturanius Verhoeff, 1931, chiefly based on new material of the type-species Nipponesmus shirinensis Chamberlin & Wang, 1953; this species is adequately redescribed and represents still another Taiwanese endemic. A key to all three currently known species of Nipponesmus Chamberlin & Wang, 1953 is given. The highly speciose Central to East Asian genus Epanerchodus Attems, 1901 is represented in Taiwan by five species, all keyed, including Epanerchodus orientalis Attems, 1901, which is long known to be highly variable in Japan and found particularly polymorphous and apparently allochthonous in Taiwan. The following synonymy is formalized: Epanerchodus orientalis orientalis Attems, 1901 = Epanerchodus orientalis takakuwai Verhoeff, 1913, syn. n. The genus Usbekodesmus Lohmander, 1932 is formally synonymized with Epanerchodus Attems, 1901, syn. n., resulting in the following new formal transfers: Epanerchodus redikorzevi (Lohmander, 1932), Epanerchodus swatensis (Golovatch, 1991), Epanerchodus varius (Geoffroy & Golovatch, 2004), Epanerchodus anachoretus (Golovatch, 1986), Epanerchodus buddhis (Golovatch, 1986), Epanerchodus occultus (Golovatch, 1986), Epanerchodus sacer (Golovatch, 1987), Epanerchodus theocraticus (Golovatch, 1990) and Epanerchodus theosophicus (Golovatch, 1986), all comb. n. ex Usbekodesmus. The distributions of all seven species of Polydesmidae occurring in Taiwan are mapped and discussed.     

Global macroecology of bird assemblages in urbanized and semi‐natural ecosystems

Aim Despite the increasing pace of urbanization, little is known about how this process affects biodiversity globally. We investigate macroecological patterns of bird assemblages in urbanized areas relative to semi‐natural ecosystems. Location World‐wide. Methods We use a database of quantitative bird surveys to compare key assemblage structure parameters for plots in urbanized and semi‐natural ecosystems controlling for spatial autocorrelation and survey methodology. We use the term ‘urbanized’ instead of ‘urban’ ecosystems as many of the plots were not located in the centre of towns but in remnant habitat patches within conurbations. Results Some macroecological relationships were conserved in urbanized landscapes. Species–area, species–abundance and species–biomass relationships did not differ significantly between urbanized and non‐urbanized environments. However, there were differences in the relationships between productivity and assemblage structure. In forests, species richness increased with productivity; in both forests and open habitats, the evenness of species abundances declined as productivity increased. Among urbanized plots, instead, both species richness and the evenness of species abundances were independent of variation in productivity. Main conclusions Remnant habitats within urbanized areas are subject to many ecological alterations, yet key macroecological patterns differ remarkably little in urbanized versus non‐urbanized plots. Our results support the need for increased conservation activities in urbanized landscapes, particularly given the additional benefits of local experiences of biodiversity for the human population. With increasing urbanization world‐wide, broad‐scale efforts are needed to understand and manage the effects of this driver of change on biodiversity.     

Constraints in the identification and interpretation of ozone as a significant predictor of effects on the supersensitive indicator Nicotiana tabacum Bel-W3 in biomonitoring studies

Biomonitoring by means of the supersensitive cultivar Nicotiana tabacum Bel-W3 is frequently used to obtain information on ozone effects on plants and estimates of ozone exposure. However, most of biomonitoring surveys do not account for other environmental variables (predictors in a statistical model) and their inherent multicollinearity with ozone. We tested the relative role of different predictors (fixed: time and site; random: ozone, temperature and humidity) on height growth and on the development of visible foliar symptoms of N. tabacum Bel-W3 plants. To do this, we investigated a relatively small area (256 km²), used a random design at every stage of the survey, controlled watering and protected plants from direct solar radiation and wind. QA/QC procedures were adopted at every stage of the investigation. Linear correlation shows that Leaf Injury Index (LII) and height increment (H.I.) positively related to ozone concentration, elevation and temperature, and negatively to relative humidity. All the predictors correlate to each other. However, relationships between response and ozone vary with the site and the monitoring week. The effect of the random factor “ozone” in combination with fixed factors “site” and “time” on the response variables was therefore formally investigated using the ANCOVA model. Besides ozone, the interactions “ozone × site” and “ozone × time” resulted always significant (0.001 < P < 0.05). While the factor “time” emphasize the inherent development of injury and growth through time, the interaction “ozone × site” pointed out the importance of local conditions. When watering, solar radiation, wind and plant characteristics were controlled, the remaining site-specific covariates of interest were temperature (T) and humidity (RH). When T and RH were accounted for by means of partial correlation analysis, no significant relationship was found between ozone and LII. On the other side, O₃ and RH resulted significant for both absolute and relative height increment. In short, LII seemed to be not solely dependent on ozone, T and RH, but showed to integrate their combined effect. On the other side, H.I. seemed to be favoured by high RH and T, and depressed by high ozone. Based on the above results, we recommend caution when handling bioindicator data: if the purpose is to infer ozone concentrations by leaf injury data, results may be affected by a serious bias, as the frequently reported correlations may be partly an artefact due to co-variation between predictors.