The plant cuticle is an extracellular hydrophobic layer that covers the aerial epidermis of all land plants, providing protection against desiccation and external environmental stresses. The past ...decade has seen considerable progress in assembling models for the biosynthesis of its two major components, the polymer cutin and cuticular waxes. Most recently, two breakthroughs in the long-sought molecular bases of alkane formation and polyester synthesis have allowed construction of nearly complete biosynthetic pathways for both waxes and cutin. Concurrently, a complex regulatory network controlling the synthesis of the cuticle is emerging. It has also become clear that the physiological role of the cuticle extends well beyond its primary function as a transpiration barrier, playing important roles in processes ranging from development to interaction with microbes. Here, we review recent progress in the biochemistry and molecular biology of cuticle synthesis and function and highlight some of the major questions that will drive future research in this field.
Background and Aims
There are a limited number of pharmacotherapies licensed for alcohol use disorders (AUDs). Baclofen is a γ‐aminobutyric acid B (GABA‐B) agonist which is used increasingly as an ...off‐label treatment. A meta‐analysis of randomized controlled trials (RCTs) was conducted to determine the efficacy of baclofen in reducing drinking behaviour, craving, depression and anxiety compared with placebo.
Methods
Random‐effects meta‐analyses were computed on outcome data from 12 RCTs comparing baclofen with placebo. Included RCTs provided data on at least one of the primary outcome measures (drinking‐related: heavy drinking days, abstinent days, abstinence rates) or secondary outcome measures (craving, anxiety, depression).
Results
Baclofen had a significant effect on abstinence rates when using intention‐to‐treat analysis total n baclofen = 307, total n control = 283: odds ratio (OR) = 2.67, 95% confidence interval (CI) = 1.03, 6.93; Z = 2.01, P = 0.04, I2 = 76%, number needed to treat = 8. No other significant effects of treatment efficacy e.g. heavy drinking days: standardized mean differences (SMD) = −0.26, 95% CI = –0.68, 0.15; Z = 1.24, P = 0.21, I2 = 95% or mechanism of action (e.g. craving: SMD = −0.13, 95% CI = −0.36, 0.09; Z = 1.18, P = 0.24, I2 = 87%) were observed. There was substantial heterogeneity in effect sizes across each analysis.
Conclusions
As a treatment for alcohol use disorders, baclofen is associated with higher rates of abstinence than placebo. However, there is no superior effect of baclofen on increasing number of abstinent days, or decreasing heavy drinking, craving, anxiety or depression. These results suggest that the current increasing use of baclofen as a treatment for alcohol use disorders is premature.
How Linguistic Metaphor Scaffolds Reasoning Thibodeau, Paul H.; Hendricks, Rose K.; Boroditsky, Lera
Trends in cognitive sciences,
November 2017, 2017-Nov, 2017-11-00, 20171101, Letnik:
21, Številka:
11
Journal Article
Recenzirano
Language helps people communicate and think. Precise and accurate language would seem best suited to achieve these goals. But a close look at the way people actually talk reveals an abundance of ...apparent imprecision in the form of metaphor: ideas are ‘light bulbs’, crime is a ‘virus’, and cancer is an ‘enemy’ in a ‘war’. In this article, we review recent evidence that metaphoric language can facilitate communication and shape thinking even though it is literally false. We first discuss recent experiments showing that linguistic metaphor can guide thought and behavior. Then we explore the conditions under which metaphors are most influential. Throughout, we highlight theoretical and practical implications, as well as key challenges and opportunities for future research.
Metaphors pervade discussions of abstract concepts and complex issues: ideas are ‘light bulbs’, crime is a ‘virus’, and cancer is an ‘enemy’ in a ‘war’.
At a process level, metaphors, like analogies, involve structure mapping, in which relational structure from the source domain is leveraged for thinking about the target domain.
Metaphors influence how people think about the topics they describe by shaping how people attend to, remember, and process information.
The effects of metaphor on reasoning are not simply the result of lexical priming.
Metaphors can covertly influence how people think. That is, people are not always aware that they have been influenced by a metaphor.
Many butterflies, birds, beetles, and chameleons owe their spectacular colors to the microscopic patterns within their wings, feathers, or skin. When these patterns, or photonic crystals, result in ...the omnidirectional reflection of commensurate wavelengths of light, it is due to a complete photonic band gap (PBG). The number of natural crystal structures known to have a PBG is relatively small, and those within the even smaller subset of notoriety, including diamond and inverse opal, have proven difficult to synthesize. Here, we report more than 150,000 photonic band calculations for thousands of natural crystal templates from which we predict 351 photonic crystal templates - including nearly 300 previously-unreported structures - that can potentially be realized for a multitude of applications and length scales, including several in the visible range via colloidal self-assembly. With this large variety of 3D photonic crystals, we also revisit and discuss oft-used primary design heuristics for PBG materials.
•Radical scavenging mechanism of structural analogues of curcumin are explored.•Hydrogen atom transfer (HAT) reactivity with •OH and •OOH radicals is evaluated.•Ortho dihydroxy groups in the ...antioxidant is important for radical stabilization.•Hispolon and polyhydroxycurcumin are more potent radical scavengers than curcumin.•Curcumin analogues show inhibition towards pro-oxidant enzyme (xanthine oxidase).
Curcumin, a ubiquitous dietary molecule, is a versatile antioxidant that fights against free radicals. The antioxidant activity of curcumin and its structural analogues such as hispolon, halfcurcumin and polyhydroxycurcumin is analyzed using density functional theory (DFT). The thermochemical parameter, bond dissociation enthalpy (BDE) is used to analyse the propensity of radical attack. The hydrogen atom transfer (HAT) energetics for the hydroxyl groups of the antioxidant molecules with •OH and •OOH in both gas and solvent media are explored. Based on ourresults, hispolon and polyhydroxycurcumin characterized by multiple hydroxyl groups arranged in ortho dihydroxy fashion are good radical scavengers. Halfcurcumin exhibited comparatively similar activity as that of curcumin. The absorption properties of these molecules are in good agreement with the reported experimental findings. The molecular docking studies revealed that these antioxidants can indirectly control the oxidative stress by favourably interacting with the pro-oxidant enzyme like xanthine oxidase.
Fruit Softening: Revisiting the Role of Pectin Wang, Duoduo; Yeats, Trevor H.; Uluisik, Selman ...
Trends in plant science,
April 2018, 2018-04-00, 20180401, Letnik:
23, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Fruit softening, which is a major determinant of shelf life and commercial value, is the consequence of multiple cellular processes, including extensive remodeling of cell wall structure. Recently, ...it has been shown that pectate lyase (PL), an enzyme that degrades de-esterified pectin in the primary wall, is a major contributing factor to tomato fruit softening. Studies of pectin structure, distribution, and dynamics have indicated that pectins are more tightly integrated with cellulose microfibrils than previously thought and have novel structural features, including branches of the main polymer backbone. Moreover, recent studies of the significance of pectinases, such as PL and polygalacturonase, are consistent with a causal relationship between pectin degradation and a major effect on fruit softening.
Fruit softening is a major determinant of shelf life and commercial value. Here, we highlight recent work that revisits the role of pectin in fruit softening and primary cell wall structure. These studies demonstrate the importance of pectin and the link between its degradation and softening in fleshy fruits.
Recent evidence suggests that many endogenous circular RNAs (circRNAs) may play roles in biological processes. However, the expression patterns and functions of circRNAs in human diseases are not ...well understood. Computationally identifying circRNAs from total RNA-seq data is a primary step in studying their expression pattern and biological roles. In this work, we have developed a computational pipeline named UROBORUS to detect circRNAs in total RNA-seq data. By applying UROBORUS to RNA-seq data from 46 gliomas and normal brain samples, we detected thousands of circRNAs supported by at least two read counts, followed by successful experimental validation on 24 circRNAs from the randomly selected 27 circRNAs. UROBORUS is an efficient tool that can detect circRNAs with low expression levels in total RNA-seq without RNase R treatment. The circRNAs expression profiling revealed more than 476 circular RNAs differentially expressed in control brain tissues and gliomas. Together with parental gene expression, we found that circRNA and its parental gene have diversified expression patterns in gliomas and control brain tissues. This study establishes an efficient and sensitive approach for predicting circRNAs using total RNA-seq data. The UROBORUS pipeline can be accessed freely for non-commercial purposes at http://uroborus.openbioinformatics.org/.
Cutin, a polyester composed mostly of oxygenated fatty acids, serves as the framework of the plant cuticle. The same types of cutin monomers occur across most plant lineages, although some ...evolutionary trends are evident. Additionally, cutins from some species have monomer profiles that are characteristic of the related polymer suberin. Compositional differences likely have profound structural consequences, but little is known about cutin's molecular organization and architectural heterogeneity. Its biological importance is suggested by the wide variety of associated mutants and gene-silencing lines that show a disruption of cuticular integrity, giving rise to numerous physiological and developmental abnormalities. Mapping and characterization of these mutants, along with suppression of gene paralogs through RNA interference, have revealed much of the biosynthetic pathway and several regulatory factors; however, the mechanisms of cutin polymerization and its interactions with other cuticle and cell wall components are only now beginning to be resolved.
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