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Robust opto-electroactive monolayers of three different RuII–terpyridyl complexes with amino and pyridyl termination are fabricated on SiOx-based substrates using siloxane-based attachment chemistry and either pyridyl or amine linkage to the preliminary prepared template. The UV–vis spectra of these monolayers display the characteristic metal-to-ligand charge-transfer bands, with a bathochromic shift compared to the spectra of the respective metalloligands dissolved in acetonitrile solution. This shift is notably larger for the pyridyl-linked monolayers compared to the amino-linked film, correlating qualitatively with the molecular grafting density. Cyclic voltammograms of the monolayers covalently attached onto indium tin oxide electrodes show reversible switching between the two redox states (Ru2+to Ru3+and vice versa), with a typical one-electron redox behavior. The sensing response of the monolayers to a series of different metal ions was tested, with the amino-decorated films showing a particularly high sensitivity to Hg2+and a close-to-linear response to this analyte in the ppm concentration range.

Spinal infections are still showing increased incidence throughout the years as our surgical capabilities increase, coupled with an overall aging population with greater number of chronic comorbidities. The management of spinal infection is of utmost importance, due to high rates of morbidity and mortality, on top of the general difficulty in eradicating spinal infection due to the ease of hematogenous spread in the spine. We aim to summarize the utility of vacuum-assisted closure (VAC) and local drug delivery systems (LDDS) in the management of spinal infections.

Bone tissue engineering using stem cells to build bone directly on a scaffold matrix often fails due to lack of oxygen at the injury site. This may be avoided by following the endochondral ossification route; herein, a cartilage template is promoted first, which can survive hypoxic environments, followed by its hypertrophy and ossification. However, hypertrophy is so far only achieved using biological factors. This work introduces a Bioglass‐Poly(lactic‐co‐glycolic acid@fibrin (Bg‐PLGA@fibrin) construct where a fibrin hydrogel infiltrates and encapsulates a porous Bg‐PLGA. The hypothesis is that mesenchymal stem cells (MSCs) loaded in the fibrin gel and induced into chondrogenesis degrade the gel and become hypertrophic upon reaching the stiffer, bioactive Bg‐PLGA core, without external induction factors. Results show that Bg‐PLGA@fibrin induces hypertrophy, as well as matrix mineralization and osteogenesis; it also promotes a change in morphology of the MSCs at the gel/scaffold interface, possibly a sign of osteoblast‐like differentiation of hypertrophic chondrocytes. Thus, the Bg‐PLGA@fibrin construct can sequentially support the different phases of endochondral ossification purely based on material cues. This may facilitate clinical translation by decreasing in‐vitro cell culture time pre‐implantation and the complexity associated with the use of external induction factors. Scaffolds for endochondral ossification should support chondrogenesis, hypertrophy, and osteogenesis. This article presents a Bioglass‐Poly(lactic‐co‐glycolic)acid@fibrin hydrogel designed to support these stages sequentially. Chondrogenesis‐primed mesenchymal stem cells seeded in the fibrin gel became hypertrophic and started osteogenesis once they reached the Bioglass‐Poly(lactic‐co‐glycolic)acid scaffold core, without external induction factors. This transformation based on material cues only may facilitate clinical translation.

The BCG vaccine, Bacille Calmette Guerin, holds the distinction of being the most widely administered vaccine. Remarkably, a century has passed since its discovery; however, puzzlingly, questions persist regarding the effectiveness of the immune response it triggers. After years of diligent observation, it has been deduced that BCG imparts immunity primarily to a specific age group, namely children. This prompts a significant query: the rationale behind BCG's limited efficacy against TB in particular age groups and populations remains elusive. Beyond vaccinations, drug therapy has emerged as an alternative route for TB prevention. Nonetheless, this approach faces challenges in the contemporary landscape, marked by the emergence of new instances of MDR-TB and XDR-TB, compounded by the financial burden of treatment. It's noteworthy that BCG remains the sole WHO-approved vaccine for TB. This comprehensive review delves into several aspects, encompassing the immune response during infection, the shortcomings of BCG in conferring immunity, and the various factors contributing to its limitations. Within this discourse, we explore potential explanations for the observed deficiencies of the BCG vaccine and consider how these insights could catalyze the development of future vaccines. The current landscape of novel vaccine development for TB is illuminated, including a spotlight on the latest vaccine candidates.

Antigen recognition of peptide-major histocompatibility complexes (pMHCs) by T cells, a key step in initiating adaptive immune responses, is performed by the T cell receptor (TCR) bound to CD3 heterodimers. However, the biophysical basis of the transmission of TCR-CD3 extracellular interaction into a productive intracellular signaling sequence remains incomplete. Here we used nuclear magnetic resonance (NMR) spectroscopy combined with mutational analysis and computational docking to derive a structural model of the extracellular TCR-CD3 assembly. In the inactivated state, CD3γε interacts with the helix 3 and helix 4-F strand regions of the TCR Cβ subunit, whereas CD3δε interacts with the F and C strand regions of the TCR Cα subunit in this model, placing the CD3 subunits on opposing sides of the TCR. This work identifies the molecular contacts between the TCR and CD3 subunits, identifying a physical basis for transmitting an activating signal through the complex.

Haemocyanin is an important non-specific immune protein present in the hemolymph of invertebrates, which have the ability to recognize the microbial pathogens and trigger the innate immune system. In this study, we isolated and purified the haemocyanin using gel filtration chromatography and investigated its microbial recognition mechanism against the invading pathogens. Kuruma shrimp Marsupenaeus japonicushaemocyanin showed the single band with a molecular weight of 76 kDa on SDS-PAGE and its molecular mass was analysed through the MALDI. Pathogen recognition mechanism of M. japonicushaemocyanin was detected through bacterial agglutination, agglutination inhibition and prophenoloxidase activity. M. japonicushaemocyanin agglutinate all human blood RBC types and showed the bacterial agglutination against all tested Gram positive Staphylococcus aureus, Enterococcus faecalisand Bacillus subtilisand Gram negative Pseudomonas aeruginosa, Proteus vulgarisand Vibrio parahaemolyticusat the concentrations ranging from 30 to 50 μg/ml. Agglutination was inhibited by 50–200 mM of N-acetylneuraminic acid, a-D-glucose, D-galactose and D-xylose. Our results suggest that, 76 kDa subunit of M. japonicushaemocyanin recognize the pathogenic surface proteins which are present on the outer membrane of the bacteria and mediates the bacterial agglutination through haemocytes. This bacterial agglutination was visualized through Confocal Laser Scanning Microscopy (CLSM). This present study would be helpful to explore the importance of haemocyanin in innate immune response of M. japonicusand its eliciting pathogen recognition mechanism leads to the development of innate immunity in crustaceans.

Lipopolysaccharide and β-1,3 glucan-binding protein (LGBP) is a family of pattern-recognition transmembrane proteins (PRPs) which plays a vital role in the immune mechanism of crustaceans in adverse conditions. Fenneropenaeus indicusLGBP-deduced amino acid has conserved potential recognition motif for β-1,3 linkages of polysaccharides and putative RGD (Arg-Gly-Asp) cell adhesion sites for the activation of innate defense mechanism. In order to understand the stimulating activity of β-1,3 glucan (β-glucan) and its interaction with LGBP,a 3D model of LGBP is generated. Molecular docking is performed with this model, and the results indicate Arg71 with strong hydrogen bond from RGD domain of LGBP. Moreover, from the docking studies, we also suggest that Arg34, Lys68, Val135, and Ala146 in LGBP are important amino acid residues in binding as they have strong bonding interaction in the active site of LGBP. In our in vitrostudies, yeast agglutination results suggest that shrimp F. indicusLGBP possesses sugar binding and recognition sites in its structure, which is responsible for agglutination reaction. Our results were synchronized with the already reported evidence both in vivoand in vitroexperiments. This investigation may be valuable for further experimental investigation in the synthesis of novel immunomodulator.

To develop an efficient reproducible protocol for a critically endangered fern, Pteris tripartita(P. tripartita) Sw. through spore culture.

Surface-confined heterometallic molecular triads (SURHMTs) were fabricated on SiOx-based solid substrates using optically rich and redox-active Fe-, Os-, and Ru-based terpyridyl complexes as metalloligands and Cu2+ions as linkers. Optical and electrochemical studies reveal efficient electronic intramolecular communication in these assemblies. The UV–vis spectra of the triads exhibit a superposition of the metal-to-ligand charge-transfer bands of individual complexes, providing a significant enlargement of the optical window, useful for application. Similarly, cyclic voltammograms of SURHMT layers show a variety of redox peaks corresponding to individual complexes as well as multi-redox states at a low potential. Interaction of a representative SURHMT assembly with redox-active NOBF4was investigated and used as a basis for configuring molecular logic gates.

In Prophenoloxidase (ProPO) cascade, two targets namely serine protease and α-2-macroglobulin are key regulators involved in the defense system of crustaceans. In biological systems, routine role of cell systems requires the understanding in protein–protein interactions through experimental and theoretical concepts, which might yield useful insights into the cellular responses. Response of cells to regulating the immune system is governed by the interactions-involved biomolecular simulations. Unfortunately, studies on the inhibitors (SP and α-2M) that negatively regulate the proPO system or melanization in penaeid shrimp are not yet available. In order to understand how these interactions change the proPO mechanism in Indian white shrimp Fenneropenaeus indicuswas determined. In F. indicus, innate immune system is in a sensitive balance of intricate interactions; elucidating these interactions by the integration of in silicoand in vitrohas great potential. We have determined the expression of both the SP and α-2M enzymes in regulatory mechanism, which are analyzed through qRT-PCR, protein–protein docking, and simulation studies. From this work, we propose a novel approach for studying an organism at the systems level by integrating genome-wide computational analysis and the gene expression data.

Heterometallic, coordination-based, binary oligomer films were fabricated on SiOx-based solid substrates using successive layer-by-layer assembly of optically rich and redox-active polypyridyl complexes, Ru(pytpy)2·2PF6(Ru-PT) and Os(pytpy)2·2PF6(Os-PT) (where pytpy = 4′-pyridyl-2,2′:6′,2″-terpyridyl). The individual oligomer chains comprised alternating Ru-PT and Os-PT units connected via Cu2+, Pd2+, Ag+, Fe2+, Co2+, or Zn2+metallo-linkers. The growth and properties of the oligomer films were monitored in detail by UV–vis spectroscopy and cyclic voltammetry. The films exhibited a linear growth upon addition of the successive building blocks, with a joint grafting density of 3.9–5.0 × 1014metallo-ligands/cm2for the final oligomer films (10 layers), corresponding to a characteristic area of 2.0–2.5 nm2/oligomer. The only exception was the Pd2+-linked film on glass that showed an exponential growth, which, however, could also be changed to the linear mode by the introduction of a conductive substrate. The combination of two different functional molecular units in the oligomer chains resulted in enhancement of the optical window and in an increase in the number of the available redox states as compared to the analogous single component assemblies.

The applicability of long wavelength (390 nm) ultraviolet (UV) light for controlled modification of protein-repelling oligo(ethylene glycol) terminated alkanethiolate (OEG-AT) monolayers on gold was studied. It was found that these films can be modified in a controlled way even at such a long wavelength, which offers versatile strategies for the design of mixed monomolecular films and chemical lithography. Using the UV treatment, protein affinity of the OEG-AT film could be either directly adjusted for nonspecific adsorption or, in combination with subsequent exchange reactions for molecules bearing a specific receptor, precisely tuned for specific adsorption. The parameters of both procedures were determined, and the results were compared with analogous data for UV light with shorter wavelengths. It occurred that 390 nm UV light is especially well suited for the fabrication of specific protein patterns. In addition, because of the long wavelength, well-developed standard optics and commercial patterning strategies can be potentially utilized.

Oligo(ethylene glycol) terminated alkanethiol (OEG-AT) monolayers can be used as templates for the fabrication of protein patterns after their modification by electron beam lithography. The OEG part of the film constituents becomes damaged by electrons, making the molecules prone to nonspecific protein adsorption or the exchange reaction with another molecule bearing a receptor for specific protein adsorption. However, for short-chain OEG-ATs, also the pristine molecules in the nonirradiated areas can be exchanged, resulting in deterioration of contrast in subsequent protein pattern. Using a modified exchange reaction, we succeeded to overcome this drawback, finding a way to control the extent of the nonpromoted exchange or even to suppress it completely. The key idea was to use not the neat solution of the receptor-bearing substituent but a mixed solution of this compound and short-chain OEG-AT species. Using a representative test system, we demonstrated the reliability of this approach and found the specific conditions for its realization. On the basis of these findings, representative nonspecific, specific, and two-component protein patterns were fabricated.

Controlled modification of protein-repelling self-assembled monolayers (SAMs) of oligo(ethylene glycol) (OEG) terminated alkanethiols (AT) by electron irradiation was investigated, and the usability of these templates for the fabrication of proteins patterns by electron beam lithography was explored. The attachment of proteins was performed either directly after irradiation, based on nonspecific interaction with the modified SAM constituents, or after the successive exchange reaction with molecular substituents bearing special receptor group for protein adsorption, based on the respective specific interaction. Characteristic dose ranges for the above approaches, viz. direct writing (DW) and irradiation-promoted exchange reaction (IPER), were defined. On the basis of these findings, patterns of both specifically and nonspecifically bound proteins of various shapes and on different length scales were fabricated in the OEG-AT templates. In addition, a simple, one-step irradiation process was suggested to prepare multiprotein patterns. As an example, side-by-side patterning of bovine serum albumin and avidin is described.

The effects of target sequence mismatches and target length mismatches on the orientation and ordering of surface-bound, poly(dT)·poly(dA) hybrids on gold were investigated using a combination of high-resolution X-ray photoelectron spectroscopy and near-edge X-ray absorption fine structure spectroscopy. It was found that the overall orientation of the probe and target strands remained upright and relatively unchanged despite the presence of up to four sequence mismatches in the target strands, although the total number of hybrids decreased with higher numbers of mismatches. Upright probes were also observed in hybrids formed with targets of shorter length, with a greater number of hybrids present in these films as compared to those formed with longer targets. These results suggest that in DNA films of relatively high densities, such as those tested here, the presence of sequence or length mismatches in target strands does not result in a large disruption of orientation and ordering in surface-bound hybrids. This finding may be useful for those seeking to maintain consistent DNA strand orientation for precise nanotechnological applications or those using DNA microarrays for biosensing purposes.

Exposure of protein-repelling oligo(ethylene glycol) (OEG) terminated alkanethiolate (AT) monolayers to ultraviolet (UV) light results in the damage of the OEG chains and photooxidation of the thiolate headgroups, which can be used for controlled tuning of protein-repelling properties within the so-called UV direct writing (UVDW) approach or for the preparation of mixed OEG-AT/specific-receptor films by so-called UV-promoted exchange reaction (UVPER). Using several model systems, we studied the effect of the wavelength (254–365 nm) on the course and efficiency of UVDW and UVPER applied to different OEG-AT matrices. The cross sections of the UV-induced damage were found to decrease significantly with increasing wavelength of UV light. In accordance with this behavior, the efficiencies of both UVDW and UVPER were maximal at a wavelength of 254 nm, somewhat lower at 313 nm, and lowest at 365 nm. Both UVDW and UVPER allowed a fine-tuning of protein affinity for nonspecific and specific adsorption, respectively, but UVDW did not occur below a certain, wavelength-dependent threshold dose. Performing UVPER below this dose enables us to suppress possible nonspecific adsorption of proteins even in the case of noncomplete exchange of the UV-damaged molecules of the primary OEG-AT matrix by receptor-bearing moieties. The obtained results are of direct relevance for the preparation of high-quality mixed OEG-AT/specific-receptor films and the fabrication of complex protein patterns by UVDW and UVPER lithography.

Transition metal complexes allow a high degree of molecular design flexibility through symmetry considerations and ligand architecture, which can be explored for the fabrication of ordered multilayer assemblies through bottom-up approach. Here we describe the preparation of such assemblies, viz. multicomponent coordination-based oligomer films on siloxane-based templates by wet-chemical layer-by-layer deposition process. In these films we combined optically rich iron and ruthenium polypyridyl complexes having pendant pyridine groups (so-called metallo-ligands) and a coinage metal (copper or silver) that acted as a linker between the polypyridyl complex moieties. The properties and structural parameters of the primary template and the oligomer films were studied by X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure spectroscopy, UV–vis spectroscopy, spectroscopic ellipsometry, atomic force microscopy, and contact angle goniometry. A linear increase in the film thickness upon addition of every next layer suggests that the long-range order of the system is determined by the octahedral structure of the metallo-ligand and square-pyramidal/tetrahedral geometry of the coinage metal linker. Spectroscopic data indicate the existence of electronic communication throughout the individual metallo-organic chains.

Circumambient tissues infection is a common complication of implanted percutaneous and permucosal devices (PDs). In order to counter the infection, the titanium abutment surface of PDs was modified to achieve antibacterial and antiadhesive activities. Titanium discs were immersed into hydroxyapatite (HA) sol containing different mass fraction silver and thermally treated to get modified discs. The modified discs become more smoother and get crystal HA coatings containing silver. Silver ion release test demonstrate the release rate is very slow and the coating is a reservoir of silver. The antibacterial and antiadhesive effects of modified discs on Staphylococcus aureus and Porphyromonas gingivalis were evaluated. Modified titanium discs with silver significantly inhibited the growth of these two bacteria compared with both the polished titanium discs control and modified titanium discs without silver. And titanium discs modified with more silver have higher antibacterial activity and less bacteria adhesion in this study. These findings indicate that titanium surface modified with the HA sol-gel containing silver could achieve antibacterial and antiadhesive activities, and the abutments of PDs are promising to be modified by this method.

Salt-induced loss of sugars and amino acids and cations (K+, Ca2+ and Mg2+) were measured in the presence or absence of varying concentrations of NaCl and Na2SO4 (7, 14, 21, 28, 35 and 42 dS/m) from germinating sunflower seeds after 120 h. Significant loss of K+ and Mg2+ was found in both the salts with increasing salinity levels. Ca2+ was excluded more in chloride-stressed seeds. Generally, there was no significant release of sugars and amino acids under salt stress. Inhibition of water uptake and the induction of K+, Ca2+ and Mg2+ loss led to changes in turgor pressure and membrane integrity which affected the germination of the seeds.

The one‐pot three‐component protocol for the synthesis of polysubstituted tetrahydroisoquinolines proceeds via a domino Knoevenagel condensation/ Michael addition/ Thorpe—Ziegler cyclization/ air promoted dehydrogenation sequence.

Biheteroaryl products are formed under ambient pressure of air via a dehydrogenative cyclization.

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