Biodegradable chitosan particles induce chemokine release and negligible arginase-1 activity compared to IL-4 in murine bone marrow-derived macrophages

Alternatively activated macrophages have been implicated in the therapeutic activity of biodegradable chitosan on wound healing, however, the mechanisms of phenotypic differentiation are still unclear.In vitro, macrophages stimulated with high doses of chitosan (?500 μg/mL) were reported to produce low-level markers associated with alternative activation (arginase-1) as well as classical activation (nitric oxide), and to undergo apoptosis. In this study, we tested the hypothesis that 40 kDa biodegradable chitosan (5–500 μg/mL) is sufficient to polarize mouse bone marrow-derived macrophages (BMDM) in vitro to an alternatively activated phenotype. Control cultures were stimulated with IL-4 (alternative activation), IFN-γ/LPS (classical activation), 1 μm diameter latex beads (phagocytosis), or left untreated. After 48 h of in vitro exposure, BMDM phagocytosed fluorescent chitosan particles or latex beads, and remained viable and metabolically active, although some cells detached with increasing chitosan and latex bead dosage. Arginase-1 was over 100-fold more strongly induced by IL-4 than by chitosan, which induced only sporadic and weak arginase-1 activity over untreated BMDM, and no nitric oxide. IFN-γ/LPS stimulated nitric oxide production and arginase-1 activity and high concentrations of inflammatory cytokines (IL-6, IL-1β, TNF-α, MIP-1α/MIP-1β), while latex beads stimulated nitric oxide and not arginase-1 activity. Chitosan or latex bead exposure, but not IL-4, tended to promote the release of several chemokines (MIP-1α/β, GM-CSF, RANTES, IL-1β), while all treatments promoted MCP-1 release. These data show that chitosan phagocytosis is not sufficient to polarize BMDM to the alternative or the classical pathway, suggesting that biodegradable chitosan elicits alternatively activated macrophages in vivo through indirect mechanisms.     

Callus induction and plant regeneration from immature embryos of Brachypodium distachyon with different chromosome numbers

The paper reports the in vitro cultivation of two commercial lines and 23 wild populations (with 10, 20 and 30 chromosomes) of Brachypodium distachyon. Callus induction was assayed on Murashige and Skoog medium containing 1 mg dm⁻³ 2,4-dichlorophenoxyacetic acid (2,4-D) with 30 g dm⁻³ of sucrose (MSs) or maltose (MSm). No significant differences were seen between the two media with respect to callus induction. Calli were transferred to MSm medium without 2,4-D but containing 0.1 mg dm⁻³ of 6-benzylaminopurine for plant regeneration. The plant regeneration response was very variable depending on the original induction medium, although no overall preference for one or the other medium was seen. The three main culture stages (callus induction, plant regeneration, and green plantlets formation) are probably differently controlled in the plants with different chromosome numbers. This supports the idea that the three cytotypes of Brachypodium cultured actually belong to different species.     

Diffuse large cell lymphoma presenting as a sacral mass and lupus anticoagulant

A 67-year-old gentleman presented to Yale-New Haven Hospital (YNHH) for assessment of a supratherapeutic INR and sacral lesion. Hematologic workup revealed elevated ESR, PT, INR, PTT, and CRP, mixing studies that failed to correct, and a positive Russell Viper Venom Test (RVVT), which confirmed the presence of lupus anticoagulant (LA), a subtype of antiphospholipid syndrome (APA). Pathology of the patient's sacral lesion revealed diffuse large B-cell lymphoma. This case provides insight into the association between APA and lymphoid neoplasm. The patient's unique presentation is in marked contrast to other reports of APA and lymphoid malignancy, which are typically associated with elevated PTT, normal PT, minimal extranodal disease, and potential thrombotic complications. Further, treatment with Rituximab-CHOP chemotherapy led to excellent clinical response with tumor remission and normalization of PT and PTT.     

Detection of SJNNV and RGNNV genotypes using a relative quantification RT‐PCR assay

Viral Encephalopathy and Retinopathy (VER), is caused by a nodavirus included within the Betanodavirus genus of the Nodaviridae family. This disease affects more than 30 marine fish species worldwide and has been a major obstacle in the aquaculture industry; control of the disease is based on virus detection, essentially in carrier specimens. This study describes a real time PCR procedure for viral nervous necrosis virus detection from several organs of sea bass, Senegalese sole, and gilt‐head sea bream, from fish displaying either clinical symptoms or asymptomatic cases. The sensitivity of this technique was about 10⁶‐fold higher than that of the conventional RT‐PCR. The newly designed primers detected nodavirus isolates belonging to the RGNNV and SJNNV genotypes.     

Bacteriocinogenic properties and in vitro probiotic potential of enterococci from Tunisian dairy products

The aim of this study was to isolate new bacteriocinogenic strains with putative probiotic potential from various Tunisian fermented milks. A total of 44 Gram-positive catalase-negative isolates were colony-purified and screened for antimicrobial activity. Of inhibitory isolates, four were identified as Enterococcus durans and one as Enterococcus faecalis using 16S rRNA gene sequence. The five strains were sensitive to penicillin G, all aminoglycosides tested, to the vancomycin, tetracycline, and chloramphenicol, and E. durans 42G and E. faecalis 61B were resistant to erythromycin. The antimicrobial substances were sensitive to proteolytic enzymes and had good biochemical stability. E. durans 61A showed a good resistance to gastric and small intestinal secretions, but were more sensitive to the duodenal conditions. Considering the safety and the stability under simulated gastrointestinal tract, it appears that the bacteriocinogenic strain E. durans 61A is a good candidate for its application as novel probiotic strain in the food industry.     

A Phosphoinositide 3-Kinase (PI3K)-serum- and glucocorticoid-inducible Kinase 1 (SGK1) Pathway Promotes Kv7.1 Channel Surface Expression by Inhibiting Nedd4-2 Protein

Epithelial cell polarization involves several kinase signaling cascades that eventually divide the surface membrane into an apical and a basolateral part. One kinase, which is activated during the polarization process, is phosphoinositide 3-kinase (PI3K). In MDCK cells, the basolateral potassium channel Kv7.1 requires PI3K activity for surface-expression during the polarization process. Here, we demonstrate that Kv7.1 surface expression requires tonic PI3K activity as PI3K inhibition triggers endocytosis of these channels in polarized MDCK. Pharmacological inhibition of SGK1 gave similar results as PI3K inhibition, whereas overexpression of constitutively active SGK1 overruled it, suggesting that SGK1 is the primary downstream target of PI3K in this process. Furthermore, knockdown of the ubiquitin ligase Nedd4-2 overruled PI3K inhibition, whereas a Nedd4-2 interaction-deficient Kv7.1 mutant was resistant to both PI3K and SGK1 inhibition. Altogether, these data suggest that a PI3K-SGK1 pathway stabilizes Kv7.1 surface expression by inhibiting Nedd4-2-dependent endocytosis and thereby demonstrates that Nedd4-2 is a key regulator of Kv7.1 localization and turnover in epithelial cells.     

From depth to regional spatial genetic differentiation of Eunicella cavolini in the NW Mediterranean

Connectivity studies in the marine realm are of great importance to understand the evolutionary potential of populations in a context of growing pressures on the marine environment. Here, we investigated the effect of the local, regional, and depth spatial scale on the population genetic structure of the yellow gorgonian Eunicella cavolini, one of the most common octocoral species of the Mediterranean hard-bottom communities. This species, along with other sessile metazoans typical of coralligenous ecosystems, plays an important role in supporting biodiversity, but is also impacted by direct and indirect consequences of human activities, such as physical destruction or mortality events due to thermal anomalies. Samples were taken from 15 sites located in the Ligurian Sea (NW Mediterranean) in two adjacent regions 100 kilometres apart, i.e. from the areas of Marseille (France) and Portofino (Genoa, Italy), and were analysed using six microsatellite loci. A pattern of isolation by distance was observed at the regional as well as the local scales. Although E. cavolini showed less genetic structure than other Mediterranean octocorallian species, we observed a significant genetic differentiation between populations a few kilometres apart. A low genetic differentiation was also observed between shallow and deep populations. The occurrence of genetically differentiated populations of E. cavolini at the scale of kilometres has important consequences for the management of this species and of the associated communities.     

Weeds ability to phytoremediate cadmium-contaminated soil

An alternative method to other technologies to clean up the soil, air and water pollution by heavy metals is phytoremediation. Therefore, a pot culture experiment was conducted at the College of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran, in 2014 to determine the potential absorption of cadmium by Portulaca oleracea (Common purslane), Solanum nigrum (Black nightshade), Abutilon theophrasti (Velvetleaf) and Taraxacum officinale (Dandelion). The type of experiment was completely randomized design with factorial arrangement and four replications. The soil in pot was treated with different rates of CdCl₂.H₂O (0 (control), 10, 20, 40, 60, and 80 mg Cd/kg soil) and the plants were sown. With increasing concentration levels, fresh weight and dry weight of shoots and roots of all plant species were reduced. The reduction severity was ranked according the following order, P. oleracea > A. theophrasti > S. nigrum > T. officinale. Bioconcentration factor (BCF), Translocation factor (TF) and Translocation efficiency (TE%) was ranked according the following order, T. officinale > S. nigrum > A. theophrasti > P. oleracea. The results of this study revealed that T. officinale and S. nigrum are effective species to phytoremediate Cd-contaminated soil.