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Reconstruction of segmental defects are popularly approached with surface engineered additively manufactured scaffolds owing to its enhanced post-surgery tissue integration properties. The present work is aimed at fabrication of Ti lattice structures using 3D printing, with a novel approach of silane chemistry-based surface modification of those Ti-surfaces with osteogenic peptides (OGP). The lattice structures with 0.6 mm strut-diameter having 0.5 mm inter-strut distance were chosen for fabrication using an extrusion-based 3D printing. Based on the evidence, it could be concluded that extrusion-based 3D printing is an optimal alternative as compared to those high cost incurring additive manufacturing processes. Therefore, OGP were grafted on the pristine Ti-surfaces using a silane chemistry based novel vapour deposition process. In vitro assessments of the surface modified scaffolds using human amniotic derived mesenchymal stem cells showed evidence of enhanced cell adhesion and viability. In vivo subcutaneous study in rat models of the surface modified Ti-scaffolds also showed enhanced tissue integration in terms of Collagen I deposition around the boundary of the tissue-integrated struts as compared to those of pristine scaffolds. The study has established that the novel surface modification technique is capable to engineer the Ti-surfaces towards enhanced tissue integration in vivo.

Mycobacterium abscessus subsp. abscessus is a rapidly growing facultative intracellular pathogen that usually infects human lung and skin epithelium. Recently, we and another group have shown that it also has the potential to colonize human gastric epithelium, but its significance with respect to gastric diseases remains unclear. Although Helicobacter pylori still remains the only definite gastric pathogen, recent studies have shown that M. abscessus subsp. abscessus also has the potential to colonize human gastric epithelium. M. abscessus subsp. abscessus is known to exhibit multidrug resistance and clarithromycin has been used as the drug of choice. We aimed to determine the clarithromycin resistance profile of 117 (74 rough and 43 smooth) gastric M. abscessus subsp. abscessus strains and to detect the point mutations in rrl and erm (41) genes conferring the resistance. Our data showed 79.48% (19 smooth and 74 rough) of M. abscessus subsp. abscessus strains were resistant to clarithromycin (MIC90 ≤ 512 μg/mL), while 20.51% (24 smooth) were susceptible (MIC90 ≤ 8 μg/mL). Nucleotide sequence analysis of the rrl gene with reference strains of M. abscessus subsp. abscessus did not show any mutation that is relevant to the clarithromycin resistance. However, analysis of erm (41) gene showed that M. abscessus subsp. abscessus strains, which were susceptible to clarithromycin had C, C, G, and C at their nucleotide positions 28, 159, 238, and 330, respectively, while the resistant strains showed T, T, A, and A at the same positions. Based on antibiogram and sequence analysis data we recommend further studies involving genomic analysis to identify the other genes involved in high clarithromycin resistance in gastric M. abscessus subsp. abscessus along with the mechanisms involved.

The gastrointestinal (GI) microbiota is essential in maintaining human health. Alteration of the GI microbiota or gut microbiota (GM) from homeostasis (i.e., dysbiosis) is associated with several communicable and non-communicable diseases. Thus, it is crucial to constantly monitor the GM composition and host–microbe interactions in the GI tract since they could provide vital health information and indicate possible predispositions to various diseases. Pathogens in the GI tract must be detected early to prevent dysbiosis and related diseases. Similarly, the consumed beneficial microbial strains (i.e., probiotics) also require real-time monitoring to quantify the actual number of their colony-forming units within the GI tract. Unfortunately, due to the inherent limitations associated with the conventional methods, routine monitoring of one’s GM health is not attainable till date. In this context, miniaturized diagnostic devices such as biosensors could provide alternative and rapid detection methods by offering robust, affordable, portable, convenient, and reliable technology. Though biosensors for GM are still at a relatively preliminary stage, they can potentially transform clinical diagnosis in the near future. In this mini-review, we have discussed the significance and recent advancements of biosensors in monitoring GM. Finally, the progresses on future biosensing techniques such as lab-on-chip, smart materials, ingestible capsules, wearable devices, and fusion of machine learning/artificial intelligence (ML/AI) have also been highlighted.

Industrial waste management and pollution control are the prime concerns today. Ceramic materials are widely used in various industries and applications; therefore, waste generation is enormous. Thus, in this work, we intend to develop silica-ceramic waste-based nano to micro-hybrid filler sustainable composites based on the percolation optimization of mechanical, thermal, and electrical properties. The developed composites exhibited improved mechanical properties and enhanced thermal conductivity (0.8 W/mK) without any surface modification. The reported value of thermal conductivity is almost double with respect to conventional carbon black filled samples (0.43 W/mK). The addition of such hybrid fillers helped in the in-situ modification of the filler network by infringement of the silica network. The composites retained their basic technical properties (tensile strength and elongation at break) even with higher loading of ceramic waste fillers. The system displayed enhanced dispersion due to the incorporation of such exclusive dual hybrid fillers. Such high loading of ceramic fillers without surface treatment or coupling agent is the first of its kind to be reported. The development of the thermal conductivity of the composites was also cross-validated using mathematical models. These composites also possess electrical conductivity in the insulative to semi-conductive domain range. These fillers can find their potential application in new-generation green and environment-friendly fillers to replace carbon black without hampering basic technical properties by reducing the carbon footprints. Due to such a combination of mechanical, electrical, and thermal attributes, these composites can find budding applications in printed circuit boards, mounts, isolators, and other e-automotive applications.

Production of green tyres by replacing carbon black (CB) with silica in natural rubber (NR) has gathered attention in automotive industries in the recent past. Incorporating high dosages of silica in NR by solid-state mixing is a huge challenge. In green tyre technology, abrasion resistance index (ARI) is crucial alongside rolling resistance, wet grip, and heat build-up. In this study, two new non-silane coupling agents have been introduced to replace bis(3-Triethoxysilylpropyl)disulfide (TESPD). Amidst them, chemical-A (sorbitol) as an alternate coupling agent of TESPD effectively achieved most properties except ARI. Hence, the naturally obtainable sustainable and cost effective chemicals A and B (B-sorbic acid) are incorporated during mastication, acting as blocking agents. Consequently, chemical-A as a blocking agent executed remarkable improvement in crucial properties, including ARI. Furthermore, the optimization study of sorbitol is accomplished based on curing time, FTIR, and XPS analysis. Subsequently, using similar quantity (0.5 phr) sorbitol in silica-CB filled NR compound evidenced better performances as tyre tread compound.

Abstract Physical unclonable functions (PUFs) are emerging as security primitives by exploiting the intrinsic device features in various hardware security solutions. This article proposes a mechanism to embed delay‐based PUFs, namely arbiter PUF and ring‐oscillator PUF, in the network‐on‐chip (NoC) architecture. These embedded PUFs are constructed by reusing already available hardware resources in NoCs, such as the crossbar switches. Pass transistors, which work as control components, have been added into the delay paths. A 5‐port NoC router has been considered and the corresponding 5 × 5 crossbar switches have been analysed after obtaining a suitable layout to embed the delay‐based PUFs. The embedded PUFs have been qualitatively analysed for their robustness against variations in supply‐voltage. Furthermore, a qualitative study on generating secret keys from the embedded PUFs has been presented. A PUF‐specific layout has been considered for implementing the NoC crossbar switches, and for extracting the RC interconnection delays. Monte Carlo simulations have been performed to evaluate the quality metrics of the proposed embedded PUFs for a 64‐bit response. Area overheads incurred for realizing the proposed embedded PUFs have been found to be 6.38% and 2.68%, for arbiter PUF and ring‐oscillator PUF, respectively. Furthermore, by incorporating the pass transistors in the control components, the reliability metrics have been found to be reasonably improved over traditional constructions of the arbiter and the ring‐oscillator PUFs.

It is increasingly being recognized that severe gastroduodenal diseases such as peptic ulcer and gastric cancer are not just the outcomes of Helicobacter pylori infection in the stomach. Rather, both diseases develop and progress due to the perfect storms created by a combination of multiple factors such as the expression of different H. pylori virulence proteins, consequent human immune responses, and dysbiosis in gastrointestinal microbiomes. In this mini review, we have discussed how the genomes of H. pylori and other gastrointestinal microbes as well as the genomes of different human populations encode complex and variable virulome–immunome interplay, which influences gastroduodenal health. The heterogeneities that are encrypted in the genomes of different human populations and in the genomes of their respective resident microbes partly explain the inconsistencies in clinical outcomes among the H. pylori-infected people.

Pathogenic potentials of the gastric pathogen, Helicobacter pylori, have been proposed, evaluated, and confirmed by many laboratories for nearly 4 decades since its serendipitous discovery in 1983 by Barry James Marshall and John Robin Warren. Helicobacter pylori is the first bacterium to be categorized as a definite carcinogen by the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO). Half of the world’s population carries H. pylori, which may be responsible for severe gastric diseases like peptic ulcer and gastric cancer. These two gastric diseases take more than a million lives every year. However, the role of H. pylori as sole pathogen in gastric diseases is heavily debated and remained controversial. It is still not convincingly understood, why most (80–90%) H. pylori infected individuals remain asymptomatic, while some (10–20%) develop such severe gastric diseases. Moreover, several reports indicated that colonization of H. pylori has positive and negative associations with several other gastrointestinal (GI) and non-GI diseases. In this review, we have discussed the state of the art knowledge on “H. pylori factors” and several “other factors,” which have been claimed to have links with severe gastric and duodenal diseases. We conclude that H. pylori infection alone does not satisfy the “necessary and sufficient” condition for developing aggressive clinical outcomes. Rather, the cumulative effect of a number of factors like the virulence proteins of H. pylori, local geography and climate, genetic background and immunity of the host, gastric and intestinal microbiota, and dietary habit and history of medicine usage together determine whether the H. pylori infected person will remain asymptomatic or will develop one of the severe gastric diseases.

Helicobacter pylori infection in stomach leads to gastric cancer, gastric ulcer, and duodenal ulcer. More than 1 million people die each year due to these diseases, but why most H. pylori-infected individuals remain asymptomatic while a certain proportion develops such severe gastric diseases remained an enigma. Several studies indicated that gastric and intestinal microbiota may play a critical role in the development of the H. pylori-associated diseases. However, no specific microbe in the gastric or intestinal microbiota has been clearly linked to H. pylori infection and related gastric diseases. Here, we studied H. pylori infection, its virulence genes, the intestinal microbiota, and the clinical status of Trivandrum residents (N = 375) in southwestern India by standard H. pylori culture, PCR genotype, Sanger sequencing, and microbiome analyses using Illumina Miseq and Nanopore GridION. Our analyses revealed that gastric colonization by virulent H. pylori strains (vacAs1i1m1cagA+) is necessary but not sufficient for developing these diseases. Conversely, distinct microbial pools exist in the lower gut of the H. pylori-infected vs. H. pylori-non-infected individuals. Bifidobacterium (belonging to the phylum Actinobacteria) and Bacteroides (belonging to the phylum Bacteroidetes) were present in lower relative abundance for the H. pylori+ group than the H. pylori- group (p < 0.05). On the contrary, for the H. pylori+ group, genus Dialister (bacteria belonging to the phylum Firmicutes) and genus Prevotella (bacteria belonging to the phylum Bacteroidetes) were present in higher abundance compared to the H. pylori- group (p < 0.05). Notably, those who carried H. pylori in the stomach and had developed aggressive gastric diseases also had extremely low relative abundance (p < 0.05) of several Bifidobacterium species (e.g., B. adolescentis, B. longum) in the lower gut suggesting a protective role of Bifidobacterium. Our results show the link between lower gastrointestinal microbes and upper gastrointestinal diseases. Moreover, the results are important for developing effective probiotic and early prognosis of severe gastric diseases.

We report the synthesis and characterization of a multifunctional composite obtained by integrating micron-sized Ni52Mn26Ga22 Heusler alloy particles into a polysulfone matrix. The Heusler alloy powders were synthesized by the ball milling of as-spun Ni52Mn26Ga22 ribbons and subsequently incorporated into a polysulfone matrix using the solution casting process. The microstructural, magnetic and thermomechanical properties of the alloy-polymer composites were investigated. X-ray diffraction and transmission electron microscopy analyses revealed the presence of a 14M modulated crystal structure along with a hierarchical twinning system down to the atomic scale. Magneto-metric and thermomechanical testing revealed that the prepared composite demonstrates a magnetocaloric effect with a usable refrigeration capacity of 3.1 J/kg under a moderate magnetic field change of 1.38 T as well as a wideband energy absorption capability at a low 5 wt% loading. The disadvantages of bulk Ni-Mn-Ga single crystals such as inherent brittleness and difficulty of production may be overcome by the incorporation of micro-size particles into a flexible polymer matrix without compromising with its functional properties. Our work demonstrates a tailored processing route to obtain multifunctional composites for possible applications in spot cooling and broadband energy absorption. Keywords: Transmission electron microscopy (TEM), Nanotwinning, Multifunctional composites, Magnetocaloric effect, Thermomechanical properties

Development of gastric diseases such as gastritis, peptic ulcer and gastric cancer is often associated with several biotic and abiotic factors. Helicobacter pylori infection is such a well-known biotic factor. However, not all H. pylori-infected individuals develop gastric diseases and not all individuals with gastric diseases are infected with H. pylori. Therefore, it is possible that other gastric bacteria may contribute to the formation and progression of gastric disease. The aim of this study was to isolate prevalent gastric bacteria under microaerobic condition and identify them by 16S rRNA gene sequence analysis. Analysis of gastric biopsies showed infection of Mycobacterium abscessus (phylum Actinobacteria) to be highly prevalent in the stomachs of subjects included. Our data show that of 129 (67 male and 62 female) patients with gastric symptoms, 96 (51 male and 45 female) showed the presence of M. abscessus in stomach tissues. Infection of M. abscessus in gastric epithelium was further confirmed by imaging with acid fast staining, immunohistochemistry and immunofluorescence. Our imaging data strongly suggested that M. abscessus is an intracellular colonizer residing inside the gastric epithelial cells rather than in macrophages. Additionally, phylogenetic analysis of the mycobacterial hsp65 gene showed that the nearest match to the M. abscessus strains isolated from our study subjects is the M. abscessus strain ATCC 19977. Surprisingly, the subjects studied, the prevalence of M. abscessus infection in stomach is even higher than the prevalence of H. pylori infection. This, to the best of our knowledge, is the first study showing the colonization of M. abscessus in human gastric mucosa among patients with various gastric symptoms. This study could provide usher in a new opportunity to understand the role of less studied gastric bacteria in the development of gastric diseases.

High-frequency ultrasound treatment is found to be a one-pot green technique to produce peptide-based nanostructures by ultrasound assisted self-assembly of oligopeptides. [Arg-Phe]4 octapeptides, consisting of alternating arginine (Arg/R) and phenylalanine (Phe/F) sequences, were subjected to 430 kHz ultrasound in aqueous solution in the absence of any external agents, to form [RF]4 nanoparticles ([RF]4-NPs), ~220 nm in diameter. A comprehensive analysis of the obtained nanoparticles demonstrated that the aromatic moieties of the oligopeptides can undergo oxidative coupling to form multiple oligomeric species, which then self-assemble into well-defined fluorescent nanoparticles. [RF]4-NPs were functionalized with polyethylene glycol (PEGylated) to improve their colloidal stability. Unlike the parent peptide, the PEGylated [RF]4-NPs showed limited cytotoxicity towards MDA-MB-231 cells. Furthermore, the intracellular trafficking of PEGylated [RF]4-NPs was investigated after incubation with MDA-MB-231 cells to demonstrate their efficient endo-lysosomal escape. This work highlights that the combined use of ultrasonic technologies and peptides enables easy fabrication of nanoparticles, with potential application in drug delivery.

More than a million people die every year due to gastric cancer and peptic ulcer. Helicobacter pylori infection in stomach is the most important reason for these diseases. Interestingly, only 10-20% of the H. pylori infected individuals suffer from these gastric diseases and rest of the infected individuals remain asymptomatic. The genotypes of H. pylori, host genetic background, lifestyle including smoking and diet may determine clinical outcomes. People from different geographical regions have different food habits, which also include several unique fermented products of plant and animal origins. When consumed raw, the fermented foods bring in fresh inocula of microbes to gastrointestinal tract and several strains of these microbes, like Lactobacillus and Saccharomyces are known probiotics. In vitro and in vivo experiments as well as clinical trials suggest that several probiotics have anti-H. pylori effects. Here we discuss the possibility of using natural probiotics present in traditional fermented food and beverages to obtain protection against H. pylori induced gastric diseases.

The vast domain of regenerative medicine comprises complex interactions between specific cells’ extracellular matrix (ECM) towards intracellular matrix formation, its secretion, and modulation of tissue as a whole. In this domain, engineering scaffold utilizing biomaterials along with cells towards formation of living tissues is of immense importance especially for bridging the existing gap of late; nanostructures are offering promising capability of mechano-biological response needed for tissue regeneration. Materials are selected for scaffold fabrication by considering both the mechanical integrity and bioactivity cues they offer. Herein, polycaprolactone (PCL) (biodegradable polyester) and ‘nature’s wonder’ biopolymer silk fibroin (SF) are explored in judicious combinations of emulsion electrospinning rather than conventional electrospinning of polymer blends. The water in oil (W/O) emulsions’ stability is found to be dependent upon the concentration of SF (aqueous phase) dispersed in the PCL solution (organic continuous phase). The spinnability of the emulsions is more dependent upon the viscosity of the solution, dominated by the molecular weight of PCL and its concentration than the conductivity. The nanofibers exhibited distinct core-shell structure with better cytocompatibility and cellular growth with the incorporation of the silk fibroin biopolymer.

Helicobacter pylori is one of the most diverse bacterial species that chronically infects more than 70% of Indian population. Interestingly, data showing microdiversity of the H. pylori strains within a particular gastric niche remained scarce. To understand the extent of genetic diversity among H. pylori strains within a given host, 30 patients with gastro-duodenal problems were subjected to endoscopy and from each patient 10 single colonies were isolated. Characterization of each of these 10 single colonies by DNA fingerprinting as well as genotyping of several important genetic markers viz. cagA, vacA, iceA, vapD, cag PAI empty site, IS605, RFLP and two other genetic segments within cag PAI revealed that all of the 30 patients were infected with more than one strain and sometimes strains with 5 to 6 types of genetic variants. Analyses of certain genetic loci showed the microdiversity among the colonies from single patient, which may be due to the recombination events during long-term carriage of the pathogen. These results suggest that most of the patients have acquired H. pylori due to repeated exposure to this pathogen with different genetic make-up, which may increase the possibility of super infections. Genetic exchanges between these unrelated H. pylori strains may support certain H. pylori variant to grow better in a given host than the parental strain and thereby increasing the possibility for the severity of the infection.