Functional Effects of Adiponectin on Endothelial Progenitor Cells

Adiponectin is an adipokine whose plasma levels are inversely correlated to metabolic syndrome components. Adiponectin protects against atherosclerosis and decreases risks in myocardial infarction. Endothelial progenitor cells (EPCs) are a heterogeneous population of circulating cells involved in vascular repair and neovascularization. EPCs number is reduced in patients with cardiovascular disease. We hypothesize that the positive effects of adiponectin against atherosclerosis are explained in part by its interactions with EPCs. Cells were obtained from healthy volunteers' blood by mononuclear cell isolation and plating on collagen‐coated dishes. Three sub‐populations of EPCs were identified and characterized using flow cytometry. EPCs' expression of adiponectin receptors, AdipoR1, and AdipoR2 was evaluated by quantitative PCR. The effects of recombinant adiponectin on EPCs' susceptibility to apoptosis were assessed. Finally, expression of neutrophil elastase by EPCs and activity of this enzyme on adiponectin processing were assessed. Quantitative PCR analysis of EPCs mRNAs showed that AdipoR1 mRNA is expressed at higher levels than AdipoR2. Expression of AdipoR1 protein was confirmed by western blot. Adiponectin significantly increased survival of two sub‐populations of EPCs in conditions of serum deprivation. Such effect could not be demonstrated in the third EPCs sub‐population. We also demonstrated that EPCs, particularly one sub‐population, express neutrophil elastase. Neutrophil elastase activity was confirmed in EPCs' conditioned media. Adiponectin protects some EPCs sub‐populations against apoptosis and therefore could modulate EPCs ability to induce repair of vascular damage. Neutrophil elastase activity of EPCs could locally modulate adiponectin activity by its involvement in the generation of the globular form of adiponectin.     

The Influence of Texting Language on Grammar and Executive Functions in Primary School Children

When sending text messages on their mobile phone to friends, children often use a special type of register, which is called textese. This register allows the omission of words and the use of textisms: instances of non-standard written language such as 4ever (forever). Previous studies have shown that textese has a positive effect on children’s literacy abilities. In addition, it is possible that children’s grammar system is affected by textese as well, as grammar rules are often transgressed in this register. Therefore, the main aim of this study was to investigate whether the use of textese influences children’s grammar performance, and whether this effect is specific to grammar or language in general. Additionally, studies have not yet investigated the influence of textese on children’s cognitive abilities. Consequently, the secondary aim of this study was to find out whether textese affects children’s executive functions. To investigate this, 55 children between 10 and 13 years old were tested on a receptive vocabulary and grammar performance (sentence repetition) task and various tasks measuring executive functioning. In addition, text messages were elicited and the number of omissions and textisms in children’s messages were calculated. Regression analyses showed that omissions were a significant predictor of children’s grammar performance after various other variables were controlled for: the more words children omitted in their text messages, the better their performance on the grammar task. Although textisms correlated (marginally) significantly with vocabulary, grammar and selective attention scores and omissions marginally significantly with vocabulary scores, no other significant effects were obtained for measures of textese in the regression analyses: neither for the language outcomes, nor for the executive function tasks. Hence, our results show that textese is positively related to children’s grammar performance. On the other hand, use of textese does not affect—positively nor negatively—children’s executive functions.     

An immunohistochemical study of serotonin-containing nerves in the colon of rats

The localization of the serotonin-like immunoreactive nerves of the rat colon was investigated by means of immunohistochemistry, utilizing an antibody against serotonin. In non-treated colons, serotonin-positive neuropils were consistently detected around the myenteric plexus. In pargyline-treated colons, serotonin-like fibres were demonstrated in association with either the small intramural blood vessels of the submucosa or the extramural nerve bundles. Treatment with 5-hydroxytryptophan (5-HTP) permitted the visualization of additional serotonin-immunoreactive fibres around the large extramural blood vessels. Immunoreactive nerve cell bodies were demonstrated in the myenteric plexus of colons treated with 5-HTP or colchicine. From these observations, it is suggested that the serotoninergic nerves of the rat colon comprise both intrinsic and extrinsic elements.     

Lysosomal Signaling Licenses Embryonic Stem Cell Differentiation via Inactivation of Tfe3

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Cyclic heptapeptides from the soil-derived fungus Clonostachys rosea

Three new cyclic heptapeptides (1–3) together with three known compounds (4–6) were isolated from a solid rice culture of the soil-derived fungus Clonostachys rosea. Fermentation of the fungus on white beans instead of rice afforded a new γ-lactam (7) and a known γ-lactone (8) that were not detected in the former extracts. The structures of the new compounds were elucidated on the basis of 1D and 2D NMR spectra as well as by HRESIMS data. Compounds 1 and 4 exhibited significant cytotoxicity against the L5178Y mouse lymphoma cell line with IC₅₀ values of 4.1 and 0.1 µM, respectively. Compound 4 also displayed cytotoxicity against the A2780 human ovarian cancer cell line with an IC₅₀ value of 3.5 µM. The preliminary structure-activity relationships are discussed.     

First efficient CRISPR‐Cas9‐mediated genome editing in Leishmania parasites

Protozoan pathogens that cause leishmaniasis in humans are relatively refractory to genetic manipulation. In this work, we implemented the CRISPR‐Cas9 system in Leishmania parasites and demonstrated its efficient use for genome editing. The Cas9 endonuclease was expressed under the control of the Dihydrofolate Reductase‐Thymidylate Synthase (DHFR‐TS) promoter and the single guide RNA was produced under the control of the U6snRNA promoter and terminator. As a proof of concept, we chose to knockout a tandemly repeated gene family, the paraflagellar rod‐2 locus. We were able to obtain null mutants in a single round of transfection. In addition, we confirmed the absence of off‐target editions by whole genome sequencing of two independent clones. Our work demonstrates that CRISPR‐Cas9‐mediated gene knockout represents a major improvement in comparison with existing methods. Beyond gene knockout, this genome editing tool opens avenues for a multitude of functional studies to speed up research on leishmaniasis.     

Malnutrition and cachexia in patients with head and neck cancer treated with (chemo)radiotherapy

AimTo highlight the problems associated with nutrition that occur in patients with squamous cell carcinoma of the head and neck (SCCHN).BackgroundSCCHN is associated with weight loss before, during and after radiotherapy or concurrent chemoradiotherapy. Because of serious consequences of malnutrition and cachexia on treatment outcome, mortality, morbidity, and quality of life, it is important to identify SCCHN patients with increased risk for the development of malnutrition and cachexia.Materials and methodsCritical review of the literature.ResultsThis review describes pathogenesis, diagnosis and treatment of malnutrition and cancer cachexia. Treatment of malnutrition and cancer cachexia includes nutritional interventions and pharmacological therapy. Advantages and disadvantages of different nutritional interventions and their effect on the nutritional status, quality of life and specific oncological treatment are presented.ConclusionsNutritional management is an essential part of care of these patients, including early screening, assessment of nutritional status and appropriate intervention.     

Growth stimulation and inhibition by salt in relation to Na<Superscript>+</Superscript> manipulating genes in xero-halophyte <Emphasis Type="Italic">Atriplex halimus</Emphasis> L.

In the present study, Na⁺ manipulating genes could contribute not only to ion homeostasis but also to growth stimulation with exposing the halophyte Atriplex halimus L. to moderate NaCl concentration. The stimulation of growth was attributed to Na⁺ accumulation inside the vacuole leading to increase leaf cell size as well as accelerate leaf cell division. Increasing the assimilatory surface could result in enhancing the photosynthetic rate. The reduction of A. halimus growth compared to optimum growth at 50 and 200 mM NaCl could be attributed to osmotic effect rather than the ionic one of salt stress. The inhibition of photosynthesis seemed to be resulted from limitation of CO₂ due to the osmotic effect on stomatal conductance rather than the activity loss of photosynthetic machinery. The depletion of starch content along with the increase in sucrose content could imply that photosynthesis may be a limiting for A. halimus growth. The fast coordinate induction of Na⁺ manipulating genes could reveal that the tolerance of A. halimus to high concentrations evolved from its ability to regulate and control Na⁺ influx and efflux. V-H ⁺-PPase may play a vital role in A. halimus tolerance to osmotic and/or ionic stress due to its kinetics of induction. It seemed that H⁺-ATPase plays a pivotal role in A. halimus tolerance to stress due to the increase in its protein level was detected with all NaCl concentrations as well as with PEG treatments. Both of these genes might be useful in improving stress tolerance in transgenic crops.