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ABSTRACTThe capacity to endure harsh wear in demanding conditions in stainless steel drops under extreme nature and applications. Protecting the surface by providing a coating layer supports the usage in harsh conditions. In this work, SS316L is coated with AlCoCrFeNi high-entropy alloy (HEA) by atmospheric plasma spray process and annealed at 600°C for 2 hours. The AlCoCrFeNi HEA exhibited spherical particles with bcc phase and 20 µm particle size. The coating morphology revealed a uniform coating with a homogeneous distribution of HEA particles over a thickness of 150 µm. The coating post-annealing offered improved microhardness by 12% than the coated sample before annealing. The wear test was executed by varying load, sliding distance, and sliding velocity at normal temperature, 400°C and 600°C and the corresponding worn surface was analysed. The coated samples after annealing showed 57.6%, 87.5%, and 65.4% improved wear resistance at normal temperature than the coated sample before annealing at minimum levels of load, sliding velocity and distance. The wear rate of coated and annealed samples revealed 5.2%, 4.5%, and 4.4% better wear resistance at 400°C than the coated samples before annealing. The worn surface morphology showcased wear mechanisms to be delamination, abrasive wear, and oxide layer formation under all conditions.

NiCoCrAlY high entropy alloy (HEA) coating (47.1 wt.% Ni, 23 wt.% Co, 17 wt.% Cr, 12.5 wt.% Al, and 0.4 wt.% Y) was deposited on a stainless steel subtract by atmospheric plasma spraying (APS). The as-deposited coating was about 300 μm thickness with 3Al, β–NiAl) that were present in the coating microstructure hinder the lattice movement during compression, according to Orowan mechanism. In addition to that, the direction of the loading to that of the orientation of the phase/splat boundaries dictate the crack propagation architecture, which results in difference in the micro-mechanical properties.

In the present study, a dry sliding wear test has been conducted to analyse the wear rate of Ti-6Al-4V alloy specimens which were fabricated using selective laser melting and conventional methods. Microstructure, micro- and nanohardness, and wear behaviour of selective laser melting specimens were investigated and compared with commercially available conventionally fabricated Ti-6Al-4V specimens. The mechanism correlating microstructure and wear behaviour of conventional and selective laser melting based Ti-6Al-4V specimens have been explained. The microhardness of the selective laser melting specimen was improved by around 22.4% over the specimen from the conventional method. The selective laser melting specimen showed broadened peaks and an increase in intensity height greater than that of the conventional specimen due to the presence of the martensite phase. The selective laser melting specimen possessed 41.4% higher nanohardness than that of the conventional specimen. The selective laser melting specimen had a 62.1% lower wear rate when compared to that of the conventional specimen. The selective laser melting specimen exhibited 62.7% less coefficient of friction than that of the conventional specimen at a 50 N load with 1.2 m/s sliding velocities. The finer needle-like microstructures of the specimen produced using the selective laser melting process had higher wear resistance, as it had higher hardness than the conventional specimen.

Abstract. Bacteriophages, or viruses of microbes, when used as a medical strategy, might be able to solve the current crisis mankind faces with the increasing number of pathogens being antibiotic-resistant, where chemical drugs seized to show any therapeutic effect. The so-called phage therapy may be one of the most promising alternatives to treat infections caused by antibiotic-resistant bacteria, which are killed after infection by a phage. While phages that destroy the host by lysis are chosen for therapy, many pharmacological and immunological aspects of phages as medicines have not been established so far. The immune system plays an important role in a process called phage acceptance where both, innate and adaptive immune responses of the host are involved. However, not only medical aspects but also social ones such as lacking public awareness or acceptance, and lack of structured regulatory guidelines are challenges that have to be addressed in the near future to establish phage therapy as a reliable and safe alternative for the treatment of infections. This review focuses on the unique pharmacological and immunological aspects of phages used in therapy.

Centrifugal casting process was applied for fabricating the functionally graded Aluminium/10% AlB2 composite under the centrifuging speed of 1200 rpm and hollow cylindrical (150 × 150 × 15 mm) component has been obtained. The outer, middle and inner surfaces of the FGM those were at the distance of 1 mm, 8 mm and 15 mm from the outer periphery were taken for three body abrasive wear test and the applied load was varied (33 N to 80 N) on these surfaces in the presence of silica sand and alumina as abrasive mediums. The wear test results showed that increase in load and increase in distance from the outer periphery of the FGM increases the wear rate. The surfaces of the FGM abraded with silica sand displays higher wear rate than the surfaces abraded through alumina. SEM analysis has been performed on the surfaces abraded by both medium and it was observed that severity of wear was less in the presence of alumina as abrasive medium during the abrasion test.

Phage therapy is the use of lytic bacteriophages to cure infections caused by bacteria. The aim of this study is to isolate and to characterize the bacteriophages against Escherichia coli isolated from clinical samples. For isolation of bacteriophages, water samples were collected from the Ganges River, and phage enrichment method was followed for phage isolation. Microbiological, genomic and lyophilization experiments were carried out to characterize the bacteriophage. Galleria mellonella was used to study the potential of phages against E. coli infection. Escherichia phage myPSH1131 belonging to Podoviridae family and found to have broad host range infectivity (n = 31) to infect Enterohemorrhagic E. coli (n = 9), Enteropathogenic E. coli (n = 6), Enterotoxigenic E. coli (n = 3), Enteroaggregative E. coli (n = 3), Uropathogenic E. coli (n = 9) and one unknown E. coli. The genome size is 76,163 base pairs (97 coding regions) and their genes show high similarity to SU10 phage. Lyophilization studies showed that the use of 1M sucrose, 2% gelatin and the combination of both 0.5M sucrose plus 1% gelatin could restore phage viability up to 20 months at 4°C. For in vivo studies, it was observed that a single phage dose can reduce the E. coli infection but to achieve 100% survival rate the infected larvae should be treated with three phage doses (20 μL, 10(3) PFU/mL) at 6 hours interval. The characterized Escherichia phage myPSH1131 was found to have broad host range activity against E. coli pathogens and in vivo studies showed that multiple doses are required for effective treatment.

The emergence of multi-drug resistance in Salmonella , causing food-borne infections, is a significant issue. With over 2,600 serovars in in Salmonella sp., it is crucial to identify specific solutions for each serovar. Phage therapy serves as an alternate treatment option. In this study, vB_SalP_792 phage was obtained from sewage, forming plaques in eight out of 13 tested clinical S. enterica isolates. Transmission electron microscopy (TEM) examination revealed a T7-like morphotype. The phage was characterized by its stability, life cycle, antibiofilm, and lytic ability in food sources. The phage remains stable throughout a range of temperatures (-20 to 70°C), pH levels (3-11), and in chloroform and ether. It also exhibited lytic activity within a range of MOIs from 0.0001 to 100. The life cycle revealed that 95% of the phages attached to their host within 3 min, followed by a 5-min latent period, resulting in a 50 PFU/cell burst size. The vB_SalP_792 phage genome has a dsDNA with a length of 37,281 bp and a GC content of 51%. There are 42 coding sequences (CDS), with 24 having putative functions and no resistance or virulence-related genes. The vB_SalP_792 phage significantly reduced the bacterial load in the established biofilms and also in egg whites. Thus, vB_SalP_792 phage can serve as an effective biocontrol agent for preventing Salmonella infections in food, and its potent lytic activity against the clinical isolates of S. enterica , sets out vB_SalP_792 phage as a successful candidate for future in vivo studies and therapeutical application against drug-resistant Salmonella infections., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Juliet, Loganathan, Neeravi, Bakthavatchalam, Veeraraghavan, Manohar and Nachimuthu.)

Phage-antibiotic combinations to treat bacterial infections are gaining increased attention due to the synergistic effects often observed when applying both components together. Most studies however focus on a single pathogen, although in many clinical cases multiple species are present at the site of infection. The aim of this study was to investigate the anti-biofilm activity of phage-antibiotic/antifungal combinations on single- and dual-species biofilms formed by P. aeruginosa and the fungal pathogen Candida albicans. The Pseudomonas phage Motto in combination with ciprofloxacin had significant anti-biofilm activity. We then compared biofilms formed by P. aeruginosa alone with the dual-species biofilms formed by bacteria and C. albicans. Here, we found that the phage together with the antifungal fluconazole was active against 6-h-old dual-species biofilms but showed only negligible activity against 24-h-old biofilms. This study lays the first foundation for potential therapeutic approaches to treat co-infections caused by bacteria and fungi using phage-antibiotic combinations., (© 2024. The Author(s).)

Introduction: The emergence of antibiotic resistance is a significant challenge in the treatment of bacterial infections, particularly in patients in the intensive care unit (ICU). Phage-antibiotic combination therapy is now being utilized as a preferred therapeutic option for infections that are multi-drug resistant in nature. Methods: In this study, we examined the combined impact of the staph phage vB_Sau_S90 and four antibiotics on methicillin-resistant Staphylococcus aureus (MRSA). We conducted experiments on three different treatment sequences: a) administering phages before antibiotics, b) administering phages and antibiotics simultaneously, and c) administering antibiotics before phages. Results: When the media was supplemented with sub-inhibitory concentrations of 0.25 μg/mL and 1 μg/mL, the size of the plaque increased from 0.5 ± 0.1 mm (in the control group with only the phage) to 4 ± 0.2 mm, 1.6 ± 0.1 mm, and 1.6 ± 0.4 mm when fosfomycin, ciprofloxacin, and oxacillin were added, respectively. The checkerboard analysis revealed a synergistic effect between the phages and antibiotics investigated, as indicated by a FIC value of less than 0.5. The combination treatment of phages and antibiotics demonstrated universal efficacy across all treatments. Nevertheless, the optimal effectiveness was demonstrated when the antibiotics were delivered subsequent to the phages. Utilizing the Galleria mellonella model, in vivo experiments showed that the combination of phage-oxacillin effectively eliminated biofilm-infected larvae, resulting in a survival rate of up to 80% in the treated groups. Discussion: Our findings highlight the advantages of using a combination of phage and antibiotic over using phages alone in the treatment of MRSA infections., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Loganathan, Bozdogan, Manohar and Nachimuthu.)

Infections caused by Pseudomonas aeruginosa are becoming increasingly difficult to treat due to the emergence of strains that have acquired multidrug resistance. Therefore, phage therapy has gained attention as an alternative to the treatment of pseudomonal infections. Phages are not only bactericidal but occasionally show activity against biofilm as well. In this study, we describe the Pseudomonas phage Motto, a T1-like phage that can clear P. aeruginosa infections in an animal model and also exhibits biofilm-degrading properties. The phage has a substantial anti-biofilm activity against strong biofilm-producing isolates ( n  = 10), with at least a twofold reduction within 24 h. To demonstrate the safety of using phage Motto, cytotoxicity studies were conducted with human cell lines (HEK 293 and RAW 264.7 macrophages). Using a previously established in vivo model, we demonstrated the efficacy of Motto in Caenorhabditis elegans, with a 90% survival rate when treated with the phage at a multiplicity of infection of 10., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Manohar, Loh, Turner, Tamizhselvi, Mathankumar, Elangovan, Nachimuthu and Leptihn.)

A lightweight AlSiBeTiV high entropy alloy (HEA) powder is synthesized by the ball milling process and is reinforced on SS410 through friction stir processing (FSP). Subsequently, the annealing process is conducted on the processed samples at 450, 600, and 750°C for 120 mins. The grains are refined at 600°C by 23.3% than the processed HEA sample. A higher microhardness of 672 HV is attained on the processed HEA sample annealed at 600°C due to the synergistic effect of FSP and annealing through refined grains. The electrochemical corrosion under a 3.5 wt.% NaCl environment, and the hot corrosion under the salt mixture environments of 75% Na 2 SO 4 +25% NaCl, and 60% Na 2 SO 4 +20% NaCl + 20% V 2 O 5 at 800°C for 50 h are investigated on the processed samples. The microstructure, induced corrosion products, and elemental distribution of the corroded surface of the annealed processed HEA sample are evaluated by morphological analysis. The induced oxidation effect enhances the Cr 2 O 3 and TiO 2 films on the corroded surfaces leading to higher corrosion resistance. A high corrosion resistance appears on the annealed processed HEA sample through the formation of a stable passive layer, hindering the pitting corrosion mechanism, grain refinement, and homogeneous distribution., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2024 The Author(s). Published by National Institute for Materials Science in partnership with Taylor & Francis Group.)

We describe the complete genome sequence of bacteriophage Motto, which infects clinical strains of Pseudomonas aeruginosa. Motto is a T1-like siphovirus related to members of the family Drexlerviridae and has a capsid width of ~57 nm and a tail length of ~255 nm. The 49.9-kb genome contains 84 protein-coding genes.

Background: Staphylococcus aureus is a pathogen endemic in India and sometimes deadly for patients in intensive care units., Objectives: To determine the antibiotic-resistance pattern, biofilm forming ability, and clonal type of S. aureus from isolates collected in Tamil Nadu (south) and the Mizoram (northeast) regions of India., Methods: We collected S. aureus isolates from diagnostic laboratories in Tamil Nadu and Mizoram. An antibiotic susceptibility test was performed according to Clinical Laboratory and Standards Institute methods. Antibiotic-resistant determinants such as mecA , mecC , blaZ , vanA , vanB , and vanC were confirmed by polymerase chain reaction (PCR). All isolates were further studied for biofilm forming ability. Enterobacterial repetitive intergenic consensus (ERIC)-PCR was used for clonal analysis., Results: A study of 206 clinical isolates showed 52.9% prevalence of methicillin-resistant S. aureus in Tamil Nadu and 49.4% in Mizoram. Minimum inhibitory concentration tests showed a high prevalence of 67% oxacillin resistance in isolates from Tamil Nadu and 49% in isolates from Mizoram. PCR showed 53% mecA in Tamil Nadu and 49% mecA in Mizoram. Vancomycin-intermediate resistance S. aureus (VISA) prevalence was lower in isolates from Tamil Nadu (4%) and Mizoram (5%). All methicillin-resistant S. aureus (MRSA) isolates formed biofilms. Clonal analysis revealed a genetic relatedness between the isolates., Conclusions: The prevalence of MRSA is high in the regions studied, with most of the clinical isolates being multidrug resistant. Adopting appropriate community-based preventive measures and establishing antimicrobial stewardship is highly recommended to minimize the dissemination in antibiotic resistance., (© 2022 Archana Loganathan et al., published by Sciendo.)

Background: Pseudomonas aeruginosa is an opportunistic pathogen that can cause a variety of infections in humans, such as burn wound infections and infections of the lungs, the bloodstream and surgical site infections. Nosocomial spread is often concurrent with high degrees of antibiotic resistance. Such resistant strains are difficult to treat, and in some cases, even reserved antibiotics are ineffective. A particularly promising therapy to combat infections of resistant bacteria is the deployment of bacteriophages, known as phage therapy. In this work, we evaluated the in vivo efficacy of two Pseudomonas phages in bacteremia mice models. For this study, non-neutropenic mice (BalB/C) were infected with P. aeruginosa AB030 strain and treated using two bacteriophages, AP025 and AP006., Results: The results showed that a single dose of phages at higher concentrations, bacteria: phage at 1:10 and 1:100 were effective in eliminating the bloodstream infection and achieving 100% mice survival., Conclusion: This study highlights the efficacy of using a single dose of phages to restore mice from bacteremia., (© 2022. The Author(s).)

The significance of advanced smart materials in recent technological research and advancement is apparent from its extensive use in present day devices and instruments. Of the various smart materials in use today, the fascinating category of shape memory alloys (SMAs) is equipped with the ability to return to a previously memorized shape under certain thermomechanical or magnetic stimuli. The unique property of shape memory effect and superelasticity displayed by these materials along with good biocompatibility and corrosion resistance make them ideal for biomedical applications. The various applications of SMAs in surgical instruments, surgical implants, and assistive and rehabilitative devices have significant effect on the day to day life of people in the present age. Majority of these biomedical devices belong to the orthodontic, orthopedic, or surgical fields. Other remarkable applications of SMAs such as in the production of prostheses and orthoses designed through the biomimetic approach are also highly influential in improving the quality of life. The present paper provides an overview of the various properties of shape memory alloys and their applications in the biomedical field over the years, that have had a significant impact on the realm of medical science.

Just over a million people died globally in 2019 due to antibiotic resistance caused by ESKAPE pathogens ( Enterococcus faecium , Staphylococcus aureus , Klebsiella pneumoniae , Acinetobacter baumannii , Pseudomonas aeruginosa , and Enterobacter species). The World Health Organization (WHO) also lists antibiotic-resistant Campylobacter and Helicobacter as bacteria that pose the greatest threat to human health. As it is becoming increasingly difficult to discover new antibiotics, new alternatives are needed to solve the crisis of antimicrobial resistance (AMR). Bacteria commonly found in complex communities enclosed within self-produced matrices called biofilms are difficult to eradicate and develop increased stress and antimicrobial tolerance. This review summarises the role of antimicrobial peptides (AMPs) in combating the silent pandemic of AMR and their application in clinical medicine, focusing on both the advantages and disadvantages of AMPs as antibiofilm agents. It is known that many AMPs display broad-spectrum antimicrobial activities, but in a variety of organisms AMPs are not stable (short half-life) or have some toxic side effects. Hence, it is also important to develop new AMP analogues for their potential use as drug candidates. The use of one health approach along with developing novel therapies using phages and breakthroughs in novel antimicrobial peptide synthesis can help us in tackling the problem of AMR.

In order to establish phage therapy as a standard clinical treatment for bacterial infections, testing of every phage to ensure the suitability and safety of the biological compound is required. While some issues have been addressed over recent years, standard and easy-to-use animal models to test phages are still rare. Testing of phages in highly suitable mammalian models such as mice is subjected to strict ethical regulations, while insect larvae such as the Galleria mellonella model suffer from batch-to-batch variations and require manual operator skills to inject bacteria, resulting in unreliable experimental outcomes. A much simpler model is the nematode Caenorhabditis elegans, which feeds on bacteria, a fast growing and easy to handle organism that can be used in high-throughput screening. In this study, two clinical bacterial strains of Escherichia coli, one Klebsiella pneumoniae, and one Enterobacter cloacae strain were tested on the model system together with lytic bacteriophages that we isolated previously. We developed a liquid-based assay, in which the efficiency of phage treatment was evaluated using a scoring system based on microscopy and counting of the nematodes, allowing increasing statistical significance compared to other assays such as larvae or mice. Our work demonstrates the potential to use Caenorhabditis elegans to test the virulence of strains of Klebsiella pneumoniae, Enterobacter cloacae, and EHEC/EPEC as well as the efficacy of bacteriophages to treat or prevent infections, allowing a more reliable evaluation for the clinical therapeutic potential of lytic phages. IMPORTANCE Validating the efficacy and safety of phages prior to clinical application is crucial to see phage therapy in practice. Current animal models include mice and insect larvae, which pose ethical or technical challenges. This study examined the use of the nematode model organism C. elegans as a quick, reliable, and simple alternative for testing phages. The data show that all the four tested bacteriophages can eliminate bacterial pathogens and protect the nematode from infections. Survival rates of the nematodes increased from <20% in the infection group to >90% in the phage treatment group. Even the nematodes with poly-microbial infections recovered during phage cocktail treatment. The use of C. elegans as a simple whole-animal infection model is a rapid and robust way to study the efficacy of phages before testing them on more complex model animals such as mice.

Non-antibiotic alternative treatments to combat the increasing number of infections caused by multidrug resistant bacteria are urgently needed. In recent years, bacteriophages have reemerged to potentially replace or complement the role of antibiotics, as bacterial viruses have the ability to inactivate pathogens. This study aimed to evaluate the synergy of phage-antibiotic combinations. A Citrobacter amalonaticus isolate was used in this study together with the phage MRM57. Eight different antibiotics with different mechanisms of action were used in combination with the phage to study the impact of the combination treatment on the minimal inhibitory concentrations. We found that antibiotic concentration dependent synergism exists, albeit at different extents, with very low numbers of phages. This demonstrates the use of phages as an adjuvant with a sublethal concentration of antibiotics as an effective therapeutic strategy.

Pseudomonas aeruginosa is a major public health concern, as drug-resistant strains increase mortality in hospital-acquired infections. We report the isolation and complete genome sequences of four lytic bacteriophages that target clinical multidrug-resistant P. aeruginosa strains.

Geezett was isolated from hospital sewage in Hangzhou, China, and exhibits lytic activity against clinical isolates of the nosocomial pathogen Klebsiella pneumoniae. The bacteriophage is a myovirus and has a double-stranded DNA (dsDNA) genome 50,707 bp long, containing 79 open reading frames (ORFs).

Background: Carbapenem resistance in Gram-negative bacteria is an ongoing public health problem of global dimensions leaving very few treatment options for infected patients., Objectives: To study the dissemination of plasmid-borne carbapenemase genes in Gram-negative bacteria from a diagnostic centre in Tamil Nadu, India., Methods: A total of 151 non-repetitive isolates belonging to 10 genera were collected between January 2015 and December 2016 from a diagnostic centre in Tamil Nadu. The isolates included Escherichia coli ( n =  57), Klebsiella pneumoniae ( n =  45), Pseudomonas aeruginosa ( n =  10), Salmonella Typhi ( n =  8), Enterobacter cloacae ( n =  8), Acinetobacter baumannii ( n =  7), Serratia marcescens ( n =  5), Achromobacter xylosoxidans ( n =  5), Proteus mirabilis ( n =  5), Klebsiella oxytoca ( n =  5) and Elizabethkingia meningoseptica ( n =  1)., Results: Of the 151 isolates, 71% ( n =  107) and 68% ( n =  103) were found to be resistant to meropenem and imipenem, respectively. The most prevalent β-lactamase gene was bla NDM-1 ( n =  22), followed by bla OXA-181 ( n =  21), bla GES-1 ( n =  11), bla OXA-51 ( n =  9), bla GES-9 ( n =  8), bla OXA-23 ( n =  7) and bla IMP-1 ( n =  3). We also observed bla OXA-23 in E. coli ( n =  4), and three K. pneumoniae were positive for both, bla OXA-23 and bla OXA-51 . Plasmid incompatibility (inc/rep) typing results showed that the resistance genes ( n =  11) were present in the isolates carrying plasmid-types IncX, IncA/C, IncFIA-FIB and IncFIIA. The plasmid-borne resistance genes in E. coli and K. pneumoniae were transferred to susceptible E. coli AB1157., Conclusions: This study highlights the prevalence of carbapenem resistance and the acquisition of plasmid-borne carbapenemase genes in Gram-negative bacteria isolated at this centre., (© The Author(s) 2021. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.)

Background: Antibiotic resistance among pathogenic bacteria has created a global emergency, prompting the hunt for an alternative cure. Bacteriophages were discovered over a century ago and have proven to be a successful replacement during antibiotic treatment failure. This review discusses on the scientific investigation of phage therapy for Gram-positive pathogens and general outlook of phage therapy clinical trials and commercialization., Main Body of the Abstract: This review aimed to highlight the phage therapy in Gram-positive bacteria and the need for phage therapy in the future. Phage therapy to treat Gram-positive bacterial infections is in use for a very long time. However, limited review on the phage efficacy in Gram-positive bacteria exists. The natural efficiency and potency of bacteriophages against bacterial strains have been advantageous amidst the other non-antibiotic agents. The use of phages to treat oral biofilm, skin infection, and recurrent infections caused by Gram-positive bacteria has emerged as a predominant research area in recent years. In addition, the upsurge in research in the area of phage therapy for spore-forming Gram-positive bacteria has added a wealth of information to phage therapy., Short Conclusion: We conclude that the need of phage as an alternative treatment is obvious in future. However, phage therapy can be used as reserve treatment. This review focuses on the potential use of phage therapy in treating Gram-positive bacterial infections, as well as their therapeutic aspects. Furthermore, we discussed the difficulties in commercializing phage drugs and their problems as a breakthrough medicine., Competing Interests: Competing interestsThe authors have no conflict of interest to declare., (© The Author(s) 2021.)

Citrobacter infections are becoming an increasingly significant health problem in aquaculture in South-Eastern countries. The objective of this study was to isolate and evaluate the potential of lytic bacteriophages against Citrobacter infections. TEM analysis revealed that the isolated phages Citrophage MRM19 and Citrophage MRM57 were identified to be Siphovirus and Podovirus family of the order Caudovirales. The phage life-cycle studies showed that Citrophage MRM19 had an adsorption time of 18 ± 1 min and a latency period of 25 ± 3 min with burst size of 110 ± 20 phages/infected cell and Citrophage MRM57 had an adsorption time of 15 ± 1 min and a latency period of 25 ± 2 min with burst size of 50 ± 5 phages/infected cell. In vitro studies indicated that the bacterial load was reduced by 5 and 7 log units within 12 h by Citrophage MRM19 and Citrophage MRM57. The in vivo efficacy of the phages was studied using zebrafish (Danio rerio) as a model organism in low-scale tanks. The study unveiled that the use of phages increased the survival up to 17%, 23%, and 26% in the case of Citrophage MRM19, Citrophage MRM57, and phage cocktail treatment, respectively. Our study indicated that bacteriophages are suitable biocontrol agents against Citrobacter spp. especially in aquaculture industry., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Pulmonary diseases of viral origin are often followed by the manifestation of secondary infections, leading to further clinical complications and negative disease outcomes. Thus, research on secondary infections is essential. Here, we review clinical data of secondary bacterial infections developed after the onset of pulmonary viral infections. We review the most recent clinical data and current knowledge of secondary bacterial infections and their treatment in SARS-CoV-2 positive patients; case reports from SARS-CoV, MERS-CoV, SARS-CoV2 and the best-studied respiratory virus, influenza, are described. We outline treatments used or prophylactic measures employed for secondary bacterial infections. This evaluation includes recent clinical reports of pulmonary viral infections, including those by COVID-19, that reference secondary infections. Where data was provided for COVID-19 patients, a mortality rate of 15.2% due to secondary bacterial infections was observed for patients with pneumonia (41 of 268). Most clinicians treated patients with SARS-CoV-2 infections with prophylactic antibiotics (63.7%, n = 1,901), compared to 73.5% ( n = 3,072) in all clinical reports of viral pneumonia included in this review. For all cases of viral pneumonia, a mortality rate of 10.9% due to secondary infections was observed (53 of 482). Most commonly, quinolones, cephalosporins and macrolides were administered, but also the glycopeptide vancomycin. Several bacterial pathogens appear to be prevalent as causative agents of secondary infections, including antibiotic-resistant strains of Staphylococcus aureus and Klebsiella pneumoniae ., (Copyright © 2020 Manohar, Loh, Nachimuthu, Hua, Welburn and Leptihn.)

Secondary bacterial infections manifest during or after a viral infection(s) and can lead to negative outcomes and sometimes fatal clinical complications. Research and development of clinical interventions is largely focused on the primary pathogen, with research on any secondary infection(s) being neglected. Here we highlight the impact of secondary bacterial infections and in particular those caused by antibiotic-resistant strains, on disease outcomes. We describe possible non-antibiotic treatment options, when small molecule drugs have no effect on the bacterial pathogen and explore the potential of phage therapy and phage-derived therapeutic proteins and strategies in treating secondary bacterial infections, including their application in combination with chemical antibiotics., (Copyright © 2020 Manohar, Loh, Athira, Nachimuthu, Hua, Welburn and Leptihn.)

Clinical pathogens, especially Gram-negative bacteria developing resistance to third-generation cephalosporins, are making clinical outcomes more complicated and serious. This study was undertaken to evaluate the distribution of CTX-M-type extended-spectrum β-lactamases (ESBLs) in Tamil Nadu, India. For this study, clinical samples were collected from five different hospitals located in Tamil Nadu and the ESBL-producing Gram-negative isolates were characterized. MIC was performed using cefotaxime and ceftazidime. The bla ESBL -producing genes were screened using multiplex PCR for the genes, CTX-M group-1, -2, -8, -9, -26. The conjugation studies were performed using Escherichia coli AB1157 as a recipient for the isolates harbouring plasmid-borne resistance following broth-mating experiment. In total, 1500 samples were collected and 599 Gram-negative bacteria were isolated that included E. coli ( n =233), Klebsiella pneumoniae ( n =182), Pseudomonas aeruginosa ( n =79), Citrobacter spp. ( n =30), Proteus mirabilis ( n =28), Salmonella spp. ( n =21), Acinetobacter baumannii ( n =12), Serratia spp . ( n =6), Shigella spp. ( n =4), Morganella morganii ( n =3) and Providencia spp. ( n =1). MIC results showed that 358 isolates were resistant to cefotaxime and ceftazidime. Further, ESBL gene-amplification results showed that 19 isolates had CTX-M group-1 gene including E. coli ( n =16) , K. pneumoniae ( n =2) and P. aeruginosa ( n =1) whereas one M. morganii isolate had CTX-M group-9, which was plasmid-borne. Through conjugation studies, 12/20 isolates were found to be involved in the transformation of its plasmid-borne resistance gene. Our study highlighted the importance of horizontal gene transfer in the dissemination of plasmid-borne bla CTX-M-type resistance genes among the clinical isolates., Competing Interests: The authors declare that there are no conflicts of interest., (© 2021 The Authors.)

Antibiotic resistance has reached alarming proportions globally, prompting the World Health Organization to advise nations to take up antibiotic awareness campaigns. Several campaigns have been taken up worldwide, mostly by governments. The government of India asked manufacturers to append a 'redline' to packages of antibiotics as identification marks and conducted a campaign to inform the general public about it and appropriate antibiotic use. We investigated whether an antibiotic resistance awareness campaign could be organized voluntarily in India and determined the characteristics of the voluntarily organized campaign by administering a questionnaire to the coordinators, who participated in organizing the voluntary campaign India. The campaign characteristics were: multiple electro-physical pedagogical and participatory techniques were used, 49 physical events were organized in various parts of India that included lectures, posters, booklet/pamphlet distribution, audio and video messages, competitions, and mass contact rallies along with broadcast of messages in 11 local languages using community radio stations (CRS) spread all over India. The median values for campaign events were: expenditure-3000 Indian Rupees/day (US$~47), time for planning-1 day, program spread-4 days, program time-4 h, direct and indirect reach of the message-respectively 250 and 500 persons/event. A 2 min play entitled 'Take antibiotics as prescribed by the doctor' was broadcast 10 times/day for 5 days on CRS with listener reach of ~5 million persons. More than 85%ofcoordinators thought that the campaign created adequate awareness about appropriate antibiotic use and antibiotic resistance. The voluntary campaign has implications for resource limited settings/low and middle income countries.

Background: The neutrophil-lymphocyte-ratio, platelet-lymphocyte-ratio, and monocyte-lymphocyte-ratio have been explored as a simple, inexpensive, and effective method for cancer prognosis. However, there are no studies that have investigated the comparative utility of these markers, in multiple cancers., Methods: The preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) guidelines were used to design this meta-analysis protocol. The final study will also be conducted under the PRISMA guidelines for systematic reviews and meta-analyses. The core bibliographic database search will be carried out by 2 reviewers working individually, with each conducting an initial screening based on titles and abstracts. The shortlisted articles will be selected for review and quantitative analysis, based on predefined inclusion and exclusion criteria. Study characteristics, relevant clinicopathological characteristics, and statistical data required for meta-analysis (hazard ratios [HRs] and 95% confidence intervals [CIs]) will be extracted and compiled into a MS Excel datasheet. Meta-analysis will be performed, using a random-effects model, and the results (pooled HR and 95% CI) will be presented in the form of a forest plot. Publication bias will also be assessed by use of Egger bias indicator test and funnel plot symmetry. If statistical data from included studies is insufficient, a qualitative literature review will be pursued.PROSPERO registration: PROSPERO CRD42019121008.

Background: Head and neck cancer (HNC) is a heterogeneous tumor at various anatomic sites and one of the most common cancers in India. Published and existing reports and studies highlight an alarming increase in the incidence, prevalence, and mortality of HNC. Despite its high incidence, there is a dearth of more precise estimates of reliable epidemiological data pertaining to HNC in India., Aim: This protocol aims to conduct a full-scale systematic review and meta-analysis on the HNC epidemiology (incidence, prevalence, and mortality) in 29 states and 7 union territories of India., Methods and Analysis: We will search for eligible published studies through PubMed, Scopus, Science Direct, MEDLINE, Web of Science, and Cochrane Review. Cancer registries such as (but not limited to) World Health Organization, International Agency for Research on Cancer, and the National Centre for Disease Informatics and Research-National Cancer Registry Program, which is maintained by the Indian Council of Medical Research, will be used for extracting relevant data using a standardized data collection form. The random-effects model of meta-analysis will be employed to aggregate the pooled estimates of relative ratios with 95% confidence intervals. Publication bias will be assessed using a funnel plot, and Egger's regression will be applied to test the symmetry of the funnel plot., Discussion: This review will provide updated evidence of the current burden of HNC in India. This will guide future studies and cancer registry reports to provide holistically representative epidemiological data., Systematic Review Registration: In accordance with the guidelines, our systematic review protocol was registered with the International Prospective Register of Systematic Reviews and was assigned the registration number, CRD42017077482., Competing Interests: None

Infections due to antibiotic resistant bacteria are increasing globally and this needs immediate attention. Bacteriophages are considered an effective alternative for the treatment of bacterial infections. The aim of this study was to isolate and characterize the bacteriophages that infect Escherichia coli , Klebsiella pneumoniae , and Enterobacter species. For this, clinical bacterial isolates of the mentioned species were obtained from diagnostic centers located in Chennai, Tamil Nadu, India. The bacteriophages were isolated from sewage water samples collected from Tamil Nadu, India. Phage isolation was performed using enrichment method and agar overlay method was used to confirm the presence of bacteriophages. All the phages were characterized for their life cycle parameters, genome analysis, and in vitro phage cocktail activity. The three bacteriophages exhibited broad host range activity: Escherichia virus myPSH2311 infecting E. coli belonging to six different pathotypes, Klebsiella virus myPSH1235 infecting K. pneumoniae belonging to four different serotypes and Enterobacter virus myPSH1140 infecting four different species of Enterobacter . Morphological observations suggested that the bacteriophages belonged to, Phieco32virus ( Escherichia virus myPSH2311), Podoviridae ( Klebsiella virus myPSH1235), and Myoviridae ( Enterobacter virus myPSH1140). The life cycles (adsorption, latent period, and cell burst) of Escherichia virus myPSH2311, Klebsiella virus myPSH1235 and Enterobacter virus myPSH1140 were found to be 26, 40, and 11 min, respectively. Genomic analysis revealed that Escherichia virus myPSH2311 is closely related to Escherichia phage vB&#95;EcoP&#95;SU10, Klebsiella virus myPSH1235 is closely related to Klebsiella phage vB&#95;KpnP&#95;KpV48 and Enterobacter virus myPSH1140 is closely related to Enterobacter phage PG7 and Enterobacter phage CC31. When phage cocktail was used against multiple bacterial mixtures, there was a reduction in bacterial load from 10 6 to 10 3 CFU/mL within 2 h. All the three characterized phages were found to have a broad host range activity and the prepared phage cocktails were effective against mixed bacterial population that are resistant to meropenem and colistin, two last resort antibiotics. Infections caused by drug resistant bacteria will be a serious threat in the future and the use of virulent bacteriophages in therapy may offer an effective solution.

Background: Phage therapy is the therapeutic use of bacteriophages to treat highly drug resistant bacterial infections. The current surge in bacteriophage therapy is motivated mainly because of the emergence of antibiotic-resistant bacteria in clinics. This study evaluated the therapeutic potential of three bacteriophages isolated against Escherichia coli ec311, Klebsiella pneumoniae kp235 and Enterobacter cloacae el140 strains using Galleria mellonella. The in vitro activity of three different phages belonging to Podoviridae and Myoviridae families was studied by the double agar overlay method against multi-drug resistant strains. Larval survivability studies were performed to evaluate the potential of phages against infection using G. mellonella., Results: All the three phages were found to have potential to infect the host bacterial strains. For in vivo studies it was observed that E. coli and E. cloacae infected larvae, should be treated with three phage doses (20 μL, 10 4 PFU/mL) at 6 h interval to achieve 100% survival rate. But in the case of K. pneumoniae, a single phage dose treatment showed promising outcome. When mixed bacterial infections (all three bacterial cultures at 10 8  CFU/mL) were tested, minimum of four doses of phage cocktail (three phages) at 6 h interval was necessary to recover the larvae. All the results were confirmed by enumerating bacteria from the larvae., Conclusion: Our data shows that although in vitro studies showed high infectivity of phages, for in vivo models multiple phage doses were required for effective treatment.

Introduction: Demographic, behavioural and environmental factors have been associated with increased risk of head and neck cancer (HNC). We will review published reports and explore connections between risk factors and HNC incidence. This protocol aims to provide strategies for a systematic review and meta-analysis of HNC risk factor analysis in India. It also provides guidelines in order to visualise obtained HNC risk factor data in the form of a heat-map highlighting variations across gender, age and geographical location., Methods and Analysis: We will identify well-established HNC risk factors and perform a comprehensive systematic review and meta-analysis to quantify each risk factor's impact on HNC incidence. A systematic search will be performed to identify the studies and published reports of HNC risk factors in India. Meta-analysis will be conducted to estimate the proportional contribution of the most prevalent risk factor in HNC on a city-wide basis in Indian states and territories., Ethics and Dissemination: The review protocol draws on publicly available anonymised data without directly involving human participants and therefore requires neither formal human ethical review nor approval by a human research ethics committee. We published an outline of the protocol in the International Prospective Register of Systematic Reviews (PROSPERO) in 2017. The results will provide an updated analysis of HNC risk factor prevalence in India, and we will discuss the applicability of rehabilitation care. We plan to disseminate the findings of this systematic review through publication in a peer-reviewed journal and presentation at relevant conference proceedings., Prospero Registration Number: CRD42017077758., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Use of the 16S rRNA gene in microbiota studies is limited by the lack of taxonomic and functional resolution. High resolution analyses are particularly important for understanding transmission and persistence of bacteria. The aim of our work was therefore to compare a novel reduced metagenome sequencing (RMS) approach with 16S rRNA gene sequencing to determine both the metagenome genetic diversity and the mother-to-child sharing of the microbiota in a cohort of 17 mother-child pairs. We found that although both approaches gave comparable results with respect to sample separation and taxonomy, RMS gave higher resolution and the potential for genomic-/functional assignment. Using RMS we estimated that the metagenome size increased from about 60 Mbp for 4-day-old children to about 225 Mbp for mothers. The 4-day-old children shared 7% of the metagenome sequences with the mothers, while the metagenome sequence sharing was >30% among the mothers. We found 15 genomes shared across >50% of the mothers, of which 10 belonged to Clostridia. Only Bacteroides showed a direct mother-child association, with B. vulgatus being abundant in both 4-day-old children and mothers. For the functional assignments, we identified a significant association between antibiotic usage during labor, and quantity of Fosfomycin resistance genes. In conclusion, our results show a higher functional and taxonomic resolution for RMS compared to 16S rRNA gene sequencing, where RMS enabled a detailed description of mother to child gut microbiota transmission - supporting a late recruitment of most gut bacteria and an effect of antibiotic treatment during labor on infant antibiotic resistance gene patterns., (Copyright © 2018. Published by Elsevier B.V.)

This study presents different fuels (Glycine and Urea) that can be used to synthesize nanocrystalline forsterite by the sol-gel combustion method. The weight change of precursor during thermal treatment was studied by thermo-gravimetric analysis (TGA). Pure forsterite was characterized by heating microscopy, Fourier transform infrared spectroscopy, X-ray Diffraction, Brunauer-Emmett-Teller, Scanning Electron Microscopy, and Energy dispersive X-ray spectroscopy. The HAP (hydroxyapatite) deposition ability, degradation and dissolution behaviour of forsterite was examined in simulated body fluid (SBF). The combusted forsterite precursor showed distinct thermal behaviour for each fuel when analyzed by heating microscopy. BET analysis showed that the particle size of forsterite synthesized using glycine was 28nm, specific surface area 65.11m 2 /g and average pore diameter 16.4nm while using urea 1.951μm, 0.939m 2 /g, and 30.5nm are the respective parameters. The dissolution of forsterite pointed to the consumption of Ca and P ions from SBF, the negligible release of Si ion into the SBF and these ionic interactions with SBF can be altered as per the material properties. The forsterite showed good antibacterial activity against S. aureus but lower activity against E. coli. The bactericidal activity of forsterite indicated that it can be used to inhibit biofilm formation in dental, bone implants and bacterial infection during surgical operations., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Purpose: The occurrence of carbapenem- and colistin-resistance among Gram-negative bacteria is increasing worldwide. The aim of this study was to understand the distribution of carbapenem- and colistin-resistance in two areas in Tamil Nadu, India., Methodology: The clinical isolates (n=89) used in this study were collected from two diagnostic centres in Tamil Nadu, India. The bacterial isolates were screened for meropenem- and colistin-resistance. Further, resistance genes blaNDM-1, blaOXA-48-like, blaIMP, blaVIM, blaKPC, mcr-1 and mcr-2 and integrons were studied. The synergistic effect of meropenem in combination with colistin was assessed., Results: A total of 89 bacterial isolates were studied which included Escherichia coli (n=43), Klebsiella pneumoniae (n=18), Pseudomonas aeruginosa (n=10), Enterobacter cloacae (n=6), Acinetobacter baumannii (n=5), Klebsiella oxytoca (n=4), Proteus mirabilis (n=2) and Salmonella paratyphi (n=1). MIC testing showed that 58/89 (65 %) and 29/89 (32 %) isolates were resistant to meropenem and colistin, respectively, whereas 27/89 (30 %) isolates were resistant to both antibiotics. Escherichia coli, K. pneumoniae, K. oxytoca, Pseudomonas aeruginosa, and Enterobacter cloacae isolates were blaNDM-1-positive (n=20). Some strains of Escherichia coli, K. pneumoniae and K. oxytoca were blaOXA-181-positive (n=4). Class 1, 2 and 3 integrons were found in 24, 20 and 3 isolates, respectively. Nine NDM-1-positive Escherichia coli strains could transfer carbapenem resistance via plasmids to susceptible Escherichia coli AB1157. Meropenem and colistin showed synergy in 10/20 (50 %) isolates by 24 h time-kill studies., Conclusion: Our results highlight the distribution of carbapenem- and colistin-resistance in Gram-negative bacteria isolated from the Tamil Nadu region in South India.

Carbapenem resistance is disseminating worldwide among Gram-negative bacteria. The aim of this study was to identify carbapenem-resistance level and to determine the mechanism of carbapenem resistance among clinical isolates from two centres in Tamil Nadu. In the present study, a total of 93 Gram-negative isolates, which is found to be resistant to carbapenem by disk diffusion test in two centres, were included. All isolates are identified at species level by 16S rRNA sequencing. Minimal inhibitory concentrations (MICs) of isolates for Meropenem were tested by agar dilution method. Presence of blaOXA, blaNDM, blaVIM, blaIMP and blaKPC genes was tested by PCR in all isolates. Amplicons were sequenced for confirmation of the genes. Among 93 isolates, 48 (%52) were Escherichia coli, 10 (%11) Klebsiella pneumoniae, nine (%10) Pseudomonas aeruginosa. Minimal inhibitory concentration results showed that of 93 suspected carbapenem-resistant isolates, 27 had meropenem MICs ≥ 2 μg/ml. The MIC range, MIC50 and MIC90 were < 0.06 to >128 μg/ml, 0.12 and 16 μg/ml, respectively. Fig. 1 . Among meropenem-resistant isolates, E. coli were the most common (9/48, 22%), followed by K. pneumoniae (7/9, 77%), P. aeruginosa (6/10, 60%), Acinetobacter baumannii (2/2, 100%), Enterobacter hormaechei (2/3, 67%) and one Providencia rettgeri (1/1, 100%). PCR results showed that 16 of 93 carried blaNDM, three oxa181, and one imp4. Among blaNDM carriers, nine were E. coli, four Klebsiella pneumoniae, two E. hormaechei and one P. rettgeri. Three K. pneumoniae were OXA-181 carriers. The only imp4 carrier was P. aeruginosa. A total of seven carbapenem-resistant isolates were negatives by PCR for the genes studied. All carbapenem-resistance gene-positive isolates had meropenem MICs >2 μg/ml. Our results confirm the dissemination of NDM and emergence of OXA-181 beta-lactamase among Gram-negative bacteria in South India. This study showed the emergence of NDM producer in clinical isolates of E. hormaechei and P. rettgeri in India.

Any novel protein introduced into the GM crops need to be evaluated for cross affinity on living organisms. Many researchers are currently focusing on the impact of Bacillus thuringiensis cotton on soil and microbial diversity by field experiments. In spite of this, in silico approach might be helpful to elucidate the impact of cry genes. The crystal a protein which was produced by Bt at the time of sporulation has been used as a biological pesticide to target the insectivorous pests like Cry1Ac for Helicoverpa armigera and Cry2Ab for Spodoptera sp. and Heliothis sp. Here, we present the comprehensive in silico analysis of Cry1Ac and Cry2Ab proteins with available in silico tools, databases and docking servers. Molecular docking of Cry1Ac with procarboxypeptidase from Helicoverpa armigera and Cry1Ac with Leucine aminopeptidase from Bos taurus has showed the 125(th) amino acid position to be the preference site of Cry1Ac protein. The structures were compared with each other and it showed 5% of similarity. The cross affinity of this toxin that have confirmed the earlier reports of ill effects of Bt cotton consumed by cattle.