The design of metal nanoparticle-modified polymer surfaces in a green and scalable way is both desirable and highly challenging. Herein, a new green low-temperature plasma-based in situ surface ...reduction strategy termed plasma electroless reduction (PER) is reported for achieving in situ metallic nanostructuring on polymer surfaces. Proof of concept for this new method was first demonstrated on hydrophilic cellulose papers. Cellulose papers were dip-coated with different metal ion (Ag+ and Au3+) solutions and then subjected to hydrogen plasma treatment for this PER process. Transmission electron microscopy (TEM) analysis has revealed that this PER process caused anisotropic growth of either gold or silver nanoparticles, resulting in the time-dependent formation of both distinct spherical nanoparticles (∼20 nm) and anisotropic 2D nanosheets. Furthermore, we have demonstrated the adaptability of this process by applying it to hydrophobic fibrous and 3D printed polymeric materials such as surgical face masks and 3D printed polylactic acid scaffolds. The PER process on these hydrophobic polymer surfaces was accomplished via a sequential combination of air plasma and hydrogen plasma treatment. The metallic nanostructuring caused by the PER process on these hydrophobic surfaces was systematically studied using different surface imaging techniques including 3D confocal laser surface scanning microscopy and scanning electron microscopy. We have also systematically optimized the PER process on the surface of 3D scaffolds via varying the concentration of the silver ion precursor and by different postprocessing methods such as sonication and medium soaking. These optimization processes were found to be very important in generating uniform metallic nanoparticle-modified 3D printed scaffolds while simultaneously improving cytocompatibility. Through joint disk diffusion and inhibitory concentration testing, the antibacterial efficacy of silver coatings on face masks and 3D scaffolds was established. Altogether, these results clearly suggest the excellent futuristic potential of this new PER method for designing metallic nanostructured interfaces for different biomedical applications.
Holstein haplotype (HH) 1, 3 and 4 are lethal mutations, responsible for early embryonic losses in Holstein Friesian (HF) cattle, worldwide. Three PCR based assays – tetra Amplification Refractory ...Mutation System PCR, PCR primer induced restriction analysis and PCR-restriction fragment length polymorphism techniques for screening of HH1, 3 and 4, respectively were developed and validated. During screening, six among 60 HF bulls were found as carrier for either of three mutations. These PCR assays are highly accurate and reproducible and can be used for screening of the haplotypes in HF cattle.
•PCR assays were developed for detection of Holstein haplotypes-1, 3, 4 associated with embryonic death in cattle.•These assays are economical, easier to handle and highly reliable.•Screening of these haplotypes resulted in presence of carriers in Indian Holstein cattle with 10 percent of frequencies.•The assays can also be used for cross-validation of the results obtained from DNA Chip based screening.
Heterobifunctional degraders, known as proteolysis targeting chimeras (PROTACs), theoretically possess a catalytic mode-of-action, yet few studies have either confirmed or exploited this potential ...advantage of event-driven pharmacology. Degraders of oncogenic EML4-ALK fusions were developed by conjugating ALK inhibitors to cereblon ligands. Simultaneous optimization of pharmacology and compound properties using ternary complex modeling and physicochemical considerations yielded multiple catalytic degraders that were more resilient to clinically relevant ATP-binding site mutations than kinase inhibitor drugs. Our strategy culminated in the design of the orally bioavailable derivative CPD-1224 that avoided hemolysis (a feature of detergent-like PROTACs), degraded the otherwise recalcitrant mutant L1196M/G1202R in vivo, and commensurately slowed tumor growth, while the third generation ALK inhibitor drug lorlatinib had no effect. These results validate our original therapeutic hypothesis by exemplifying opportunities for catalytic degraders to proactively address binding site resistant mutations in cancer.
Abstract Purpose The aim of this study was to compare efficacy between the single non-compression titanium miniplate and single three-dimensional titanium miniplate in mandibular angle fracture ...treatment. Method and materials A prospective study of 20 patients with mandibular angle fractures. Patients were randomly categorized into two groups with 10 patients in each group. Group-I patients were treated with single 2.0 mm conventional titanium miniplate, Group-II patients were treated with single 2.0 mm three-dimensional titanium miniplate according to Champy's principles. Parameters such as stability of fracture fragments, occlusion, mouth opening, additional fixation required and complications were evaluated at different time intervals. Results In Group-I, about 40% ( n = 4) of patients showed unstable fracture fragments on immediate postoperative day whereas in Group-II only 10% ( n = 1) of patients with fracture instability. In Group-I, 30% ( n = 3) had mild occlusal derangement and 20% ( n = 2) had deranged occlusion on immediate postoperative day, where as in Group-II only 20% ( n = 2) of patients had mild occlusal derangement. Additional fixation required in 30% ( n = 3) of patients in group-I, and 10% ( n = 1) in Group-II. 20% ( n = 2) of patients in Group-I developed infection. All patients in both the groups had inadequate mouth opening on immediate post operative day, later resumed normal mouth opening. 10% ( n = 1) in group-I and 20% ( n = 2) of patients in group-II presented with postinjury/preoperative inferior alveolar nerve sensory disturbance with no incidence of postoperative sensory disturbance. None of the patients in both the groups had malunion, nonunion, plate fracture, and loosening of plates and screws. Conclusion 3-D titanium miniplates showed more favorable results compared to single conventional titanium miniplate with respect to initial interfragmentary stability and complications.
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•Efficient surface modification of biomaterials by magneto-plasma processing (MPP) is demonstrated for the first time.•MPP offers increased modification rates than non-magnetized ...plasma processing.•MPP enable us to tune the shape of plasma plume for selective functionalization using single or quadrupole magnet assembly.•Surface activated biomaterials are ideal scaffolds for tissue engineering and bio-interfaces.
We report a method to increase the efficiency of radio-frequency (RF) generated plasma for surface modification of electrospun biomaterials by introducing magnetization. The x-ray photoelectron spectroscopy (XPS) reveals the oxygen/carbon ratio is consistently higher for various exposure times for magnetized plasma than non-magnetized plasma. The principle demonstrated here supports the use of magnetic fields as an additional controllable parameter in plasma processing of biomaterials and is extendable to other plasma sources. The surface activation and functionalization of biomaterials has impact in the broader arena of tissue engineering applications in that magneto-plasma processing (MPP) enables us to tune the shape of plasma plume for selective enhanced functionalization of surface of scaffolds, which in turn has wide applications for basic cell-patterning science and in applied regenerative medicine.
Chloroplasts and photosynthesis are the physiologically fateful arenas of salinity stress. Morphological and anatomical alterations in the leaf tissue, ultrastructural changes in the chloroplast, ...compromise in the integrity of the three-layered chloroplast membrane system, and defects in the light and dark reactions during the osmotic, ionic, and oxidative phases of salt stress are conversed in detail to bring the salinity-mediated physiological alterations in the chloroplast on to a single platform. Chloroplasts of salt-tolerant plants have evolved highly regulated salt-responsive pathways. Thylakoid membrane remodeling, ion homeostasis, osmoprotection, upregulation of chloroplast membrane and stromal proteins, chloroplast ROS scavenging, efficient retrograde signalling, and differential gene and metabolite abundance are the key attributes of optimal photosynthesis in tolerant species. This review throws light into the comparative mechanism of chloroplast and photosynthetic response to salinity in sensitive and tolerant plant species.
We report a novel and facile organosilane plasma polymerization method designed to improve the surface characteristics of poly(tetrafluoroethylene) (PTFE). We hypothesized that the polymerized silane ...coating would provide an adhesive surface for endothelial cell proliferation due to a large number of surface hydroxyl groups, while the large polymer networks on the surface of PTFE would hinder platelet attachment. The plasma polymerized PTFE surfaces were then systematically characterized via different analytical techniques such as FTIR, XPS, XRD, Contact angle, and SEM. The key finding of the characterization is the time-dependent deposition of an organosilane layer on the surface of PTFE. This layer was found to provide favorable surface properties to PTFE such as a very high surface oxygen content, high hydrophilicity and improved surface mechanics. Additionally, in vitro cellular studies were conducted to determine the bio-interface properties of the plasma-treated and untreated PTFE. The important results of these experiments were rapid endothelial cell growth and decreased platelet attachment on the plasma-treated PTFE compared to untreated PTFE. Thus, this new surface modification technique could potentially address the current challenges associated with PTFE for blood contact applications, specifically poor endothelial cell growth and risk of thrombosis.
The mechanisms by which microvascular damage leads to dermal fibrosis in diffuse cutaneous systemic sclerosis (dcSSc) are unclear. We hypothesized that microvascular pericytes constitute a cellular ...link between microvascular damage and fibrosis by transdifferentiating into myofibroblasts. We used a combination of immunohistochemistry and double immunofluorescence labelling of frozen skin biopsies taken from normal and dcSSc patients to determine whether a phenotypic link between pericytes and myofibroblasts exists in dcSSc. Using alpha-smooth muscle actin, the ED-A splice variant of fibronectin (ED-A FN) and Thy-1 to identify myofibroblasts, we demonstrated the presence of myofibroblasts in fibrotic dcSSc skin. Myofibroblasts were totally absent from control skin, atrophic stage dcSSc skin and non-lesional skin. Using double immunofluorescence labelling, both myofibroblasts and pericytes were shown to express ED-A FN and Thy-1 in dcSSc skin but not in control skin. Proliferating cell nuclear antigen was also expressed by myofibroblasts and pericytes in dcSSc skin while being absent in control skin. These observations suggest that the presence of myofibroblasts may represent a transitional phase during the fibrotic stages of dcSSc and that Thy-1+ve pericytes participate in the fibrogenic development of dcSSc by synthesizing ED-A FN, which may be associated with a proliferation and transition of pericytes and fibroblasts to myofibroblasts, thus linking microvascular damage and fibrosis.
Children with neurofibromatosis type I (NF1) have a higher predisposition for low-grade astrocytomas of the optic pathway, commonly referred to as optic pathway gliomas (OPGs). OPGs can result in ...visual deterioration. Treatment outcomes in OPG-NF1 management are often reported around tumor stabilization. We sought to compare vision outcomes associated with different OPG treatment strategies to inform about this important functional metric. A meta-analysis exploring the different modalities to treat children with OPG-NF1 was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using multiple databases. Of the 113 articles identified in the search, 23 full text articles, representing 564 patients, were included for review. These articles included retrospective, prospective, and randomized controlled studies on observation (n=9), chemotherapy (n=19), radiation therapy (n=6), and surgery (n=7). Of the patients undergoing observation, 87% (60/69) demonstrated stable acuity. In the chemotherapy studies, 27.3% (72/264) demonstrated improved acuity/visual field and/or visual-evoked potential amplitudes, 39.4% (104/264) stable acuity, and 33.3% (88/264) deterioration. Both the radiation and surgical treatments reported worsening acuity at 90.9% (10/11) and 73.3% (11/15), respectively. Causal associations are not known. Indications for and timing of treatment choice warrant larger scale study to provide further understanding.
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