Olive Varieties under UV-B Stress Show Distinct Responses in Terms of Antioxidant Machinery and Isoform/Activity of RubisCO

In recent decades, atmospheric pollution led to a progressive reduction of the ozone layer with a consequent increase in UV-B radiation. Despite the high adaptation of olive trees to the Mediterranean environment, the progressive increase of UV-B radiation is a risk factor for olive tree cultivation. It is therefore necessary to understand how high levels of UV-B radiation affect olive plants and to identify olive varieties which are better adapted. In this study we analyzed two Italian olive varieties subjected to chronic UV-B stress. We focused on the effects of UV-B radiation on RubisCO, in terms of quantity, enzymatic activity and isoform composition. In addition, we also analyzed changes in the activity of antioxidant enzymes (SOD, CAT, GPox) to get a comprehensive picture of the antioxidant system. We also evaluated the effects of UV-B on the enzyme sucrose synthase. The overall damage at biochemical level was also assessed by analyzing changes in Hsp70, a protein triggered under stress conditions. The results of this work indicate that the varieties (Giarraffa and Olivastra Seggianese) differ significantly in the use of specific antioxidant defense systems, as well as in the activity and isoform composition of RubisCO. Combined with a different use of sucrose synthase, the overall picture shows that Giarraffa optimized the use of GPox and opted for a targeted choice of RubisCO isoforms, in addition to managing the content of sucrose synthase, thereby saving energy during critical stress points.     

Genome Subtyping of Autochthonous Bacillus Species Isolated from Iru,a Fermented Parkia biglobosa Seed

Phylogenetic relationship and strains sub-typing of Bacillus species isolated from iru, a traditional fermented condiment in Africa were studied using polyphasic genomic approaches and the profiles compared with bacilli isolated from similar Asian condiments. The 16S rRNA gene sequencing identified the strains as Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus cereus, Bacillus licheniformis, Bacillus pumilus, and Brevibacillus formosus. The phylogenetic analysis conducted showed five distinct clusters with genetic relatedness among B. subtilis and B. amyloliquefaciens strains from Africa and Asia. Amplified ribosomal DNA restriction analysis (ARDRA) successfully differentiated species of B. subtilis phylogeny from B. cereus. Combined analyses of ARDRA, internal transcribed spacer-polymerase chain reaction (ITS-PCR), ITS-PCR-restriction fragment length polymorphism (ITS-PCR-RFLP) and randomly amplified polymorphic DNA (RAPD-PCR) further confirmed B. subtilis and B. amyloliquefaciens as the dominant Bacillus species associated with fermentation of iru, and revealed high strains genetic diversity, while multilocus sequence analysis (MLSA) data distinguished B. cereus from B. thuringiensis. This information is essential for selection of starter cultures with desirable functional attributes to guarantee product consistency and safety quality of traditional fermented foods.     

Going, going, gone: Localizing abrupt offsets of moving objects.

When a moving object abruptly disappears, this profoundly influences its localization by the visual system. In Experiment 1, 2 aligned objects moved across the screen, and 1 of them abruptly disappeared. Observers reported seeing the objects misaligned at the time of the offset, with the continuing object leading. Experiment 2 showed that the perceived forward displacement of the moving object depended on speed and that offsets were localized accurately. Two competing representations of position for moving objects are proposed: 1 based on a spatially extrapolated internal model, and the other based on transient signals elicited by sudden changes in the object trajectory that can correct the forward-shifted position. Experiment 3 measured forward displacements for moving objects that disappeared only for a short time or abruptly reduced contrast by various amounts. Manipulating the relative strength of the 2 position representations in this way resulted in intermediate positions being perceived, with weaker motion signals or stronger transients leading to less forward displacement. This 2-process mechanism is advantageous because it uses available information about object position to maximally reduce spatio-temporal localization errors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Distinct Tomato Cultivars Are Characterized by a Differential Pattern of Biochemical Responses to Drought Stress

Future climate scenarios suggest that crop plants will experience environmental changes capable of affecting their productivity. Among the most harmful environmental stresses is drought, defined as a total or partial lack of water availability. It is essential to study and understand both the damage caused by drought on crop plants and the mechanisms implemented to tolerate the stress. In this study, we focused on four cultivars of tomato, an economically important crop in the Mediterranean basin. We investigated the biochemical mechanisms of plant defense against drought by focusing on proteins specifically involved in this stress, such as osmotin, dehydrin, and aquaporin, and on proteins involved in the general stress response, such as HSP70 and cyclophilins. Since sugars are also known to act as osmoprotectants in plant cells, proteins involved in sugar metabolism (such as RuBisCO and sucrose synthase) were also analyzed. The results show crucial differences in biochemical behavior among the selected cultivars and highlight that the most tolerant tomato cultivars adopt quite specific biochemical strategies such as different accumulations of aquaporins and osmotins. The data set also suggests that RuBisCO isoforms and aquaporins can be used as markers of tolerance/susceptibility to drought stress and be used to select tomato cultivars within breeding programs.     

Osteosynthesis revision in war fractures

A comparison of primary suturing and a new laser weld technique is described for the microsurgical repair of the inferior alveolar nerve in Wistar rats. A reliable method of exposure of the inferior alveolar nerve has been developed in order to allow intraosseous repairs of the nerve involving suturing with 10:0 nylon and a laser weld technique using an albumin-based solder, containing indocynine cardiogreen, plus an infrared (810 nm wavelength) diode laser. Seven cases of microsuture and laser weld repairs were performed with a 29.4% reduction in total operating time in the laser weld group. Histochemical analysis showed comparable mean neuron counts and mean tracer uptake by neurons for the microsuture and laser weld groups. Giant cell reactions were identified in two of the primary suture cases and axon deflection in three cases demonstrating possible advantages of the laser weld technique which showed no adverse reactions by axons or epineurium to the coagulative repair with the solder. The technique of laser weld repair, on initial analysis, therefore appears comparable with traditional suture repairs and indeed may possess several advantages. Further studies are recommended.     

Perceptual organization of moving stimuli modulates the flash-lag effect.

When a visual stimulus is flashed at a given location the moment a second moving stimulus arrives at the same location, observers report the flashed stimulus as spatially lagging behind the moving stimulus (the flash-lag effect). The authors investigated whether the global configuration (perceptual organization) of the moving stimulus influences the magnitude of the flash-lag effect. The results indicate that a flash presented near the leading portion of a moving stimulus lags significantly more than a flash presented near the trailing portion. This result also holds for objects consisting of several elements that group to form a unitary percept of an object in motion. The present study demonstrates a novel interaction between the global configuration of moving objects and the representation of their spatial position and may provide a new and useful tool for the study of perceptual organization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Changes in vitamin E concentration after surgery and anesthesia

The aim of this randomized study was to examine changes in vitamin E concentration in female subjects (age 30-60, ASA I) after cholecystectomy and halothane (N = 16) or isoflurane (N = 16) anaesthesia. Vitamin E concentration was measured two days before, and then one, five and twenty-four hours and four days after surgery. High-pressure liquid chromatography was used for its determination. Simultaneously activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyltransferase (GGT) were determined. Statistical analysis: ANOVA, Tukay HSD test. The research has been accepted by the Drugs Committee of the Karlovac County Hospital. Preoperative vitamin E concentrations in the halothane group were 8.69 +/- 2.35 micrograms/L, median 8.67 micrograms/L and in the isoflurane group 9.43 +/- 2.4 micrograms/L, median 9.08 micrograms/L. Statistically lower vitamin E concentrations compared with preoperative values were noted one hour (P < 0.05), 5 hours (P < 0.01), 24 hours (P < 0.01), as well as 4 days (P < 0.01) after the operation. The lowest vitamin E concentrations were noted 24 hours after the operation with statistically insignificantly higher values in the isoflurane group (halothane group 5.98 +/- 2.08 micrograms/L, isoflurane group 6.58 +/- 1.51 micrograms/L). Analyzing enzyme (ALT, AST and GGT) pre- and postoperative values, no statistically significant differences between the investigated groups and during the time were observed. Statistically significant differences were found between individual measurement times, with no statistical significance of the differences between the halothane and isoflurane groups. It seems that neither the difference in halothane and isoflurane biotransformation nor their distinct effect on perfusion of some organs are the determining factors in post-operative changes in vitamin E concentration.     

Cued in: advances and opportunities in freshwater chemical ecology

We focus this mini-review on how naturally occurring chemical cues mediate ecological interactions, especially interspecific competition and predation in freshwater communities. Although freshwater chemical ecology lags behind terrestrial and marine chemical ecology, we identify recent progress toward: (1) identifying the chemical composition of cues important in food web interactions, e.g., specific glucosinolates, benzyl succinoates, and lignoids as deterrents to herbivory on freshwater macrophytes; (2) employing a nonreductionist approach that tests for emergent responses to suites of multiple chemical cues, e.g., trade-offs in snail refuge-seeking behavior in the presence of chemical cues from both fish and crayfish; (3) investigating how abiotic forces, such as hydrodynamics, impact chemical communication across a broad spatial and temporal scale, e.g., drift responses of mayfly nymphs to whole-stream additions of trout cue; and (4) quantifying the importance of genetic variability, e.g., how chemical cues change selective pressures of local environments. The questions of interest in freshwater chemical ecology cross taxonomic boundaries; traverse broad spatial and temporal scales; demonstrate nonlinear, unpredictable results; and necessitate a multidisciplinary approach for adequate understanding.     

Distinct Functional Alterations and Therapeutic Options of Two Pathological De Novo Variants of the T292 Residue of GABRA1 Identified in Children with Epileptic Encephalopathy and Neurodevelopmental Disorders

Mutations of GABA_AR have reportedly led to epileptic encephalopathy and neurodevelopmental disorders. We have identified a novel de novo T292S missense variant of GABRA1 from a pediatric patient with grievous global developmental delay but without obvious epileptic activity. This mutation coincidentally occurs at the same residue as that of a previously reported GABRA1 variant T292I identified from a pediatric patient with severe epilepsy. The distinct phenotypes of these two patients prompted us to compare the impacts of the two mutants on the receptor function and to search for suitable therapeutics. In this study, we used biochemical techniques and patch-clamp recordings in HEK293 cells overexpressing either wild-type or mutated rat recombinant GABA_ARs. We found that the α1T292S variant significantly increased GABA-evoked whole-cell currents, shifting the dose–response curve to the left without altering the maximal response. In contrast, the α1T292I variant significantly reduced GABA-evoked currents, shifting the dose–response curve to the right with a severely diminished maximum response. Single-channel recordings further revealed that the α1T292S variant increased, while the α1T292I variant decreased the GABA_AR single-channel open time and open probability. Importantly, we found that the T292S mutation-induced increase in GABA_AR function could be fully normalized by the negative GABA_AR modulator thiocolchicoside, whereas the T292I mutation-induced impairment of GABA_AR function was largely rescued with a combination of the GABA_AR positive modulators diazepam and verapamil. Our study demonstrated that α1T292 is a critical residue for controlling GABA_AR channel gating, and mutations at this residue may produce opposite impacts on the function of the receptors. Thus, the present work highlights the importance of functionally characterizing each individual GABA_AR mutation for ensuring precision medicine.