Publications by authors named "Roshan Nepal"

Introduction: In chronic rhinosinusitis (CRS), the congestion and blockage of the nose can cause anaerobic conditions within the sinus cavities which may promote the expression of virulence and antibiotic resistance genes in invading pathogens. is a facultative anaerobic bacteria and causes severe recalcitrant CRS. In this study, we aimed to evaluate the antimicrobial resistance of isolates of CRS patients in planktonic and biofilm form grown in aerobic and anaerobic conditions.

View Article and Find Full Text PDF

Chronic rhinosinusitis (CRS) is an inflammatory condition of the sinonasal mucosa. Despite being a common health issue, the exact cause of CRS is yet to be understood. However, research suggests that , particularly in its biofilm form, is associated with the disease.

View Article and Find Full Text PDF

Phage therapy has recently been revitalized in the West with many successful applications against multi-drug-resistant bacterial infections. However, the lack of geographically diverse bacteriophage (phage) genomes has constrained our understanding of phage diversity and its genetics underpinning host specificity, lytic capability, and phage-bacteria co-evolution. This study aims to locally isolate virulent phages against uropathogenic Escherichia coli (E.

View Article and Find Full Text PDF

Chronic rhinosinusitis (CRS) is a common chronic sinonasal mucosal inflammation associated with biofilm and relapsing infections. This study aimed to determine rates of persistence and pathoadaptation in CRS patients by investigating the genomic relatedness and antibiotic resistance/tolerance in longitudinally collected clinical isolates. A total of 68 .

View Article and Find Full Text PDF

Chronic rhinosinusitis (CRS) is a persistent inflammation of the sinus mucosa. Recalcitrant CRS patients are unresponsive to medical and surgical interventions and often present with nasal polyps, tissue eosinophilia, and Staphylococcus aureus dominant mucosal biofilms. However, S.

View Article and Find Full Text PDF

Non-Tuberculous Mycobacterial Pulmonary Disease (NTM-PD) caused by Mycobacterium abscessus is a frequent complication in patients with cystic fibrosis (CF) that worsens lung function over time. Currently, there is no cure for NTM-PD, hence new therapies are urgently required. Disrupting bacterial iron uptake pathways using gallium-protoporphyrin (IX) (GaPP), a heme analog, has been proposed as a novel antibacterial approach to tackle multi-drug resistant M.

View Article and Find Full Text PDF

Chronic rhinosinusitis (CRS) represents chronic inflammation of the sinus mucosa characterised by dysfunction of the sinuses' natural defence mechanisms and induction of different inflammatory pathways ranging from a Th1 to a Th2 predominant polarisation. Recalcitrant CRS is associated with Staphylococcus aureus dominant mucosal biofilms; however, S. aureus colonisation of the sinonasal mucosa has also been observed in healthy individuals challenging the significance of S.

View Article and Find Full Text PDF

The transmission of healthcare-associated infections (HCAIs) in healthcare settings is a serious challenge in the medical fraternity. Medical devices, such as stethoscopes used by healthcare workers (HCWs), are likely to harbor a considerable number of pathogenic microbes, which may result in the transmission of HCAIs. This study sought to investigate bacterial contamination of stethoscopes used by HCWs at Bharatpur Hospital, Nepal.

View Article and Find Full Text PDF

Spinel compounds ABX consist of both tetrahedral (AX) and octahedral (BX) environments with the former forming a diamond lattice and the latter a geometrically frustrated pyrochlore lattice. Exploring the fascinating physical properties and their correlations with structural features is critical in understanding these materials. FeMnO has been reported to exhibit one structural transition and two successive magnetic transitions.

View Article and Find Full Text PDF

Skin and soft tissue infection (SSTI) caused by atypical mycobacteria such as Mycobacterium abscessus and Mycobacterium avium intracellulare complex (MAIC) have increased in recent years. Current therapeutic options are limited, and hence new and better therapies are urgently required. Colloidal Silver (CS) has been identified for its widespread antibacterial properties and silver-impregnated dressings have been used for SSTIs caused by various pathogens.

View Article and Find Full Text PDF

Summary: In recent years, there has been an increasing interest in bacteriophages, which has led to growing numbers of bacteriophage genomic sequences becoming available. Consequently, there is a need for a rapid and consistent genomic annotation tool dedicated for bacteriophages. Existing tools either are not designed specifically for bacteriophages or are web- and email-based and require significant manual curation, which makes their integration into bioinformatic pipelines challenging.

View Article and Find Full Text PDF

Background: Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen frequently causing healthcare-associated infections. The apocalyptic rise of antimicrobial resistance has rekindled interest in age-old phage therapy that uses phages (viruses that infect bacteria) to kill the targeted pathogenic bacteria. Because of its specificity, phages are often considered as potential personalized therapeutic candidate for treating bacterial infections.

View Article and Find Full Text PDF

Application of bacteriophages (phages) to treat complex multidrug-resistant bacterial infection is gaining traction because of its efficacy and universal availability. However, as phages are specific to their host, a diverse collection of locally isolated phage from various geographical locations is required to formulate a wide host range phage cocktail. Here, we report morphological and genomic features of three newly isolated phages from river water of the urban region in Kathmandu, Nepal, targeting three different bacteria (Escherichia coli, Klebsiella pneumoniae and Salmonella enterica.

View Article and Find Full Text PDF

Prophages affect bacterial fitness on multiple levels. These include bacterial infectivity, toxin secretion, virulence regulation, surface modification, immune stimulation and evasion and microbiome competition. Lysogenic conversion arms bacteria with novel accessory functions thereby increasing bacterial fitness, host adaptation and persistence, and antibiotic resistance.

View Article and Find Full Text PDF

Infectious diseases caused by antibiotic-resistant bacteria in planktonic and biofilm form are difficult to treat with conventional antibiotics. Silver nanoparticles (Ag NPs) can be used as alternatives to antibiotics and can alter the susceptibility of bacteria to antibiotics. Here, the antibacterial properties of 16 different antibiotics and Ag NPs, alone and in combination, were tested against clinical isolates of Pseudomonas aeruginosa (n=3), Staphylococcus aureus (n=3) and methicillin-resistant Staphylococcus aureus (MRSA) (n=2) isolated from chronic rhinosinusitis (CRS) patients.

View Article and Find Full Text PDF

Phage therapy is one of the most promising alternatives to antibiotics as we face global antibiotic resistance crisis. However, the pharmacokinetics (PK) and pharmacodynamics (PD) of phage therapy are largely unknown. In the present study, we aimed to evaluate the PK/PD of a locally isolated virulent novel øKp_Pokalde_002 (, C1 morphotype) that infects carbapenem-resistant (Kp56) using oral and intraperitoneal (IP) route in a mouse model.

View Article and Find Full Text PDF

The presence of surface/deep defects in 4d- and 5d-perovskite oxide (ABO, B = Nb, Ta, Mo, etc.) nanoparticles (NPs), originating from multivalent B-site cations, contributes to suppressing their metallic properties. These defect states can be removed using a H/Ar thermal treatment, enabling the recovery of their electronic properties (i.

View Article and Find Full Text PDF

Background: Global emergence of carbapenem-resistant Klebsiella pneumoniae is a major public health concern. Phage therapy - application of lytic phage to kill pathogenic bacteria - is considered as one of the promising alternatives to tackle this antibiotic crisis in recent days. This study aimed to isolate, characterize and evaluate therapeutic efficacy of a novel K.

View Article and Find Full Text PDF

Magnetic insulators are important materials for a range of next-generation memory and spintronic applications. Structural constraints in this class of devices generally require a clean heterointerface that allows effective magnetic coupling between the insulating layer and the conducting layer. However, there are relatively few examples of magnetic insulators that can be synthesized with surface qualities that would allow these smooth interfaces and precisely tuned interfacial magnetic exchange coupling, which might be applicable at room temperature.

View Article and Find Full Text PDF

Transition metal stannides are usually semiconductors with a narrow band gap. We report experimental investigation on metallic IrSnMn(= 0 and 0.56).

View Article and Find Full Text PDF

Spin glass (SG) is a magnetic state with spin structure incommensurate with lattice and charge. Fundamental understanding of its behavior has a profound impact on many technological problems. Here, we present a novel case of interface-induced spin glass behavior via self-assembly of single-crystalline NiO microcolumns in a single-crystalline NiFeO matrix.

View Article and Find Full Text PDF