Phyto-Functionalized Silver Nanoparticles Derived from Conifer Bark Extracts and Evaluation of Their Antimicrobial and Cytogenotoxic Effects

Silver nanoparticles synthesized using plant extracts as reducing and capping agents showed various biological activities. In the present study, colloidal silver nanoparticle solutions were produced from the aqueous extracts of Picea abies and Pinus nigra bark. The phenolic profile of bark extracts was analyzed by liquid chromatography coupled to mass spectrometry. The synthesis of silver nanoparticles was monitored using UV-Vis spectroscopy by measuring the Surface Plasmon Resonance band. Silver nanoparticles were characterized by attenuated total reflection Fourier transform infrared spectroscopy, Raman spectroscopy, dynamic light scattering, scanning electron microscopy, energy dispersive X-ray and transmission electron microscopy analyses. The antimicrobial and cytogenotoxic effects of silver nanoparticles were evaluated by disk diffusion and Allium cepa assays, respectively. Picea abies and Pinus nigra bark extract derived silver nanoparticles were spherical (mean hydrodynamic diameters of 78.48 and 77.66 nm, respectively) and well dispersed, having a narrow particle size distribution (polydispersity index values of 0.334 and 0.224, respectively) and good stability (zeta potential values of −10.8 and −14.6 mV, respectively). Silver nanoparticles showed stronger antibacterial, antifungal, and antimitotic effects than the bark extracts used for their synthesis. Silver nanoparticles obtained in the present study are promising candidates for the development of novel formulations with various therapeutic applications

Activation of ERAD Pathway by Human Hepatitis B Virus Modulates Viral and Subviral Particle Production

Hepatitis B virus (HBV) belongs to the Hepadnaviridae family of enveloped DNA viruses. It was previously shown that HBV can induce endoplasmic reticulum (ER) stress and activate the IRE1-XBP1 pathway of the unfolded protein response (UPR), through the expression of the viral regulatory protein X (HBx). However, it remained obscure whether or not this activation had any functional consequences on the target genes of the UPR pathway. Of these targets, the ER degradation-enhancing, mannosidase-like proteins (EDEMs) are thought to play an important role in relieving the ER stress during UPR, by recognizing terminally misfolded glycoproteins and delivering them to the ER-associated degradation (ERAD). In this study, we investigated the role of EDEMs in the HBV life-cycle. We found that synthesis of EDEMs (EDEM1 and its homologues, EDEM2 and EDEM3) is significantly up-regulated in cells with persistent or transient HBV replication. Co-expression of the wild-type HBV envelope proteins with EDEM1 resulted in their massive degradation, a process reversed by EDEM1 silencing. Surprisingly, the autophagy/lysosomes, rather than the proteasome were involved in disposal of the HBV envelope proteins. Importantly, inhibition of the endogenous EDEM1 expression in HBV replicating cells significantly increased secretion of both, enveloped virus and subviral particles. This is the first report showing that HBV activates the ERAD pathway, which, in turn, reduces the amount of envelope proteins, possibly as a mechanism to control the level of virus particles in infected cells and facilitate the establishment of chronic infections

Managing Knowledge for Innovations in Wind Power Industry : A Case Study

On one side Innovation, innovation systems and knowledge management are two topics have been discussed so much by scholars before. The advantages gained through knowledge management by fostering innovation which entails competitive advantage. On the other side, an emerging interest has represented the relationship between the renewable industry and environmental innovations. The oil crises and some forum discussion of environmental impact have fuelled the interest for Renewable Energy especially on wind energy. Most likely there hasn’t been any research knowledge management in wind power companies which is an emerging and terribly needs knowledge to innovate and bring more products. As a result there is a need to look more into the role of knowledge management in wind mill companies and explore how innovation can be triggered by successful knowledge management and how this process provide competitive advantage in wind power industry

Intraocular Pressure Measurement after Penetrating Keratoplasty

Assessing the intraocular pressure is a difficult but crucial task in the follow-up of patients that have undergone penetrating keratoplasty. Early recognition of elevated intraocular pressure and/or glaucoma and establishment of the appropriate treatment is essential to ensure the best possible visual outcome for patients dealing with this feared complication. Although Goldmann applanation tonometry is still the gold standard for measuring the intraocular pressure, its limitations in postkeratoplasty eyes, due to postoperative modified corneal morphology, have led to the search for more suitable alternatives. This review is the result of a comprehensive literature search in the MEDLINE database that aims to present glaucoma in the context of perforating keratoplasty, the corneal properties with impact on ocular pressure measurement, and the results achieved with the most important tonometers that have been studied in this pathology. Goldmann applanation tonometry remains the reference for intraocular pressure assessment even in corneas after penetrating keratoplasty. However, some promising alternatives have emerged, the most important of which are the Pascal dynamic contour tonometry, the Tono-Pen XL, the ocular response analyzer, and the iCare. All have advantages and disadvantages but have proved to be appropriate alternatives, especially in cases in which Goldmann applanation tonometry cannot be used

More than simple hepatic cysts

Caroli diseaseis a rare congenital disorder that classically causes saccular dilatation of the bile ducts. The complications of Caroli include choledochal cysts with recurrent cholangitis, abscess formation, septicaemia, intrahepatic lithiasis and amyloidosis.We report a rare case of a young female with Caroli disease pointing out the intrahepatic lithiasis as a rare complication of the disease. Learning points Caroli disease is an uncommon condition that should be considered in the differential diagnosis of hepatic essential cysts. Clinically, it is characterized of recurrent episodes of fever and pain. The correct and early diagnostic is important because of the different complications and treatment unlike the essential hepatic cysts

Azo-polysiloxanes as new supports for cell cultures

International audienceThe paper introduces a new class of materials with azo-polysiloxanic structure bearing the property to generate nano-structured surfaces by laser irradiation. The ability to modulate the optical response of the film, through a modification of the polymer chemical structure, has been investigated. The azo-materials were tested for their ability to support cell adhesion and growth, with very promising results. A future use of these materials as growth support in cell cultures is of great interest, due to an easy, one step-method to generate the surface relief grating and to the possibility to introduce a large range of chemical modifications due to the presence of the chlorobenzyl groups in the polymeric side-chain

EDEM1 silencing results in inhibition of the HBV envelope protein degradation.

<p>HEK293T were transfected with pCiS in the presence or absence of either EDEM1 siRNA (siEDEM1) or scrambled siRNA (siCtrl). Transfected cells were split in equal amounts and analysed for the efficiency of EDEM1 silencing by RT-real-time PCR (A) or the biosynthesis of the S, M and L proteins, by Western blotting using the anti-S Abs. When silencing of the over-expressed EDEM1 was investigated, the pCMVEDEM1 was added in the transfection mixture containing either pCiS or pCiS and EDEM1siRNA, as indicated (D, C). The expression level of EDEM1 (C) and S (D) was determined by Western blotting using the corresponding Abs. Calnexin (Cnx) level was used as total protein-gel loading control.</p