Co-chaperone involvement in knob biogenesis implicates host-derived chaperones in malaria virulence

The pathology associated with malaria infection is largely due to the ability of infected human RBCs to adhere to a number of receptors on endothelial cells within tissues and organs. This phenomenon is driven by the export of parasite-encoded proteins to the host cell, the exact function of many of which is still unknown. Here we inactivate the function of one of these exported proteins, PFA66, a member of the J-domain protein family. Although parasites lacking this protein were still able to grow in cell culture, we observed severe defects in normal host cell modification, including aberrant morphology of surface knobs, disrupted presentation of the cytoadherence molecule PfEMP1, and a total lack of cytoadherence, despite the presence of the knob associated protein KAHRP. Complementation assays demonstrate that an intact J-domain is required for recovery to a wild-type phenotype and suggest that PFA66 functions in concert with a HSP70 to carry out host cell modification. Strikingly, this HSP70 is likely to be of host origin. ATPase assays on recombinant protein verify a functional interaction between PFA66 and residual host cell HSP70. Taken together, our data reveal a role for PFA66 in host cell modification, strongly implicate human HSP70s as being essential in this process and uncover a new KAHRP-independent molecular factor required for correct knob biogenesis.

Facile Synthesis of Coral Reef-Like ZnO/CoS2 Nanostructure on Nickel Foam as an Advanced Electrode Material for High-Performance Supercapacitors

Nanocomposite electrodes receive much attention because of their excellent energy storage nature. Electrodes for supercapacitors have come a major source of interest. In this pursuit, the current work elucidates binder-free coral reefs resembling ZnO/CoS2 nanoarchitectures synthesized on the surface of Ni foams employing the cost-effective hydrothermal route. The Zno/CoS2 nanocomposite demonstrated excellent battery-type behavior, which can be employed for supercapcitor application. Various analyses were carried out in the current study, such as X-ray diffraction and high-resolution scanning electron microscopy, which allowed defining the crystalline nature and morphology of surface with ZnO/CoS2 nanoarchitectures. Electrochemical measures such as cyclic voltammetry, galvanostatic charge discharge, and potentiostatic impedance spectroscopy confirmed the battery-type behavior of the material. The synthesized precursors of binder-free ZnO/CoS2 nanostructures depicted an excellent specific capacity of 400.25 C·g−1 at 1 A·g−1, with a predominant cycling capacity of 88. 2% and retention holding of 68% at 10 A·g−1 and 2 A·g−1, even after 4000 cycles, representing an improvement compared to the pristine ZnO and CoS2 electroactive materials. Therefore, the electrochemical and morphological analyses suggest the excellent behavior of the ZnO/CoS2 nanoarchitectures, making them promising for supercapacitors.

Co-chaperone involvement in knob biogenesis implicates host-derived chaperones in malaria virulence

The pathology associated with malaria infection is largely due to the ability of infected human erythrocytes to adhere to a number of receptors on endothelial cells within tissues and organs. This phenomenon is driven by the export of parasite-encoded proteins to the host cell, the exact function of many of which is still unknown. Here we inactivate the function of one of these exported proteins, PFA66, a member of the J-domain protein family. Although parasites lacking this protein were still able to grow in cell culture, we observed severe defects in normal host cell modification, including aberrant morphology of surface knobs, disrupted presentation of the cytoadherence molecule PfEMP1, and a total lack of cytoadherence, despite the presence of the knob associated protein KAHRP. Complementation assays demonstrate that an intact J-domain is required for recovery to a wild-type phenotype and suggest that PFA66 functions in concert with a HSP70 to carry out host cell modification. Strikingly, this HSP70 is likely to be of host origin.Taken together, our data reveal a role for PFA66 in host cell modification, implicate human HSP70 as also being essential in this process, and uncover a KAHRP-independent mechanism for correct knob biogenesis. Our observations open up exciting new avenues for the development of new anti-malarials.

Coating based on basalt protection metal structures

The paper present the results of the synthesis of a new refractory coating based on basalt for the protection of metal construction under conditions of cavitation. Initial basalt samples obtained from the locality Vrelo - Kopaonik. The basalt based refractory filler was obtained by crushing and grinding selected samples of basalt rock. XRD, SEM and optical microscopy methods were used to characterize the obtained filler samples. The research defined the composition of basalt -based coating with epoxy resinbased binder, organic additives and organic solvent. The resistance properties of protective coatings applied to metal surface were investigated using the ultrasonic vibration method with a stationary sample according to the ASTM G 32 standard. To evaluate the resistance of the sample surface to the action of cavitation, the sample surface was examined before and during testing. The surface of the samples was monitored by scanning electron microscopy in order to analyze the morphology of surface damage. Computer image analysis according to the Image Pro Plus program was applied to assess the damage to the sample surface. The obtained test results showed high resistance of the coating layers to the effect of cavitation, with small mass losses, small damage to the coating surface and a cavitation rate of 0,1 mg/min.

Preparation of Waterborne Polyurethane-Based Macroporous Sponges as Wound Dressings

Recently, eco-friendly and biologically harmless products of waterborne polyurethane (WPU) instead of solvent-borne polyurethane have been strongly progressed in both industries and research areas. Accordingly, we developed a WPU-based macroporous sponge as a skin tissue engineering matrix. Also, the WPU dispersion in water was modified by using a foaming agent in order to create creamy emulsion resulting in enlarging surface area wherein cells could adhere, grow, and proliferate. We investigated the effect of a foaming agent on the morphology of surface and internal structure, wettability. In vitro studies also confirmed enhanced adherence and proliferation of cells with increased metabolic rate. These results proved that the use of foaming agent could alter the internal structure, surface property, and biocompatibility.

Studying some Optical Properties of Polyethylene Glycol Doped with Al- Nanoparticles

This research aims to improve some optical properties of polyethylene glycol (PEG) by adding different weight percentages of aluminium nanoparticles )0, 2, 4, 6 and 8) % and for achieving a new composite material with improved characteristics. nanocomposite thin films were prepared by solution casting method with different weight percentages of Al nanoparticles. The samples were characterized by X-ray diffraction (XRD), FTIR and UV-visible spectrophotometer. FTIR-spectra of (PEG-Al) nanocomposite show various special bands of bending for groups (C=O, C–O, C–H, C-N, C-I). Optical microscopy images illustrate the morphology of surface for (PEG) composite. The optical properties measurement by using (UV–VIS) spectrophotometer at wavelength range )220 – 1100(nm were determined. Results show that the absorbance spectrum increased with increase the weight percentages of Al-nanoparticles and the values of absorption coefficient have increased as well as refractive index values increased with the addition of aluminium nanoparticle