Multidrug-resistant among Non-Fermenting Gram-negative Bacteria Isolated in the Department of Microbiology of a Tertiary Care Centre.

Introduction: Infection caused by Non-fermenting Gram-negative bacteria (NFGNB) like Pseudomonas aeruginosa and Acinetobacter baumannii leads to life-threatening conditions. These bacteria are often multidrug-resistant which leads to limited therapeutic options leading to treatment failure. Little information is available regarding the prevalence and resistance pattern of such bacteria in our country.

Selective Transfer Hydrogenation of C=O and Conjugated C=C Bonds Using An NHC-Based Pincer (CNC)Mn Complex in Methanol.

Base metal catalyzed transfer hydrogenation reactions using methanol is highly challenging. Employing a single N-heterocyclic carbene (NHC)-based pincer (CNC)Mn complex, chemoselective single and double transfer hydrogenation of α, β-unsaturated ketones to saturated ketones or alcohols by utilizing methanol as the hydrogen source is disclosed. The protocol was tolerant towards the selective transfer hydrogenation of C=C or C=O bonds in the presence of several other reducible functional groups and led to the synthesis of several biologically relevant molecules and natural products.

Multidrug Resistant Escherichia coli among Urinary Samples of Patients with Urinary Tract Infection in the Microbiology Department of a Tertiary Care Center: A Descriptive Cross-Sectional Study.

Introduction: Urinary Tract Infection one of the most common and manageable infections still holds its position as a major public health issue worldwide due to an increase in the number of multidrug resistant bacteria. This study aims to find out the prevalence of multidrug resistant Escherichia coli among urinary samples of patients with urinary tract infections in the microbiology Department of a tertiary care center.

Methods: A descriptive cross-sectional study was carried out at a tertiary care centre from 8 August 2018 to 9 January 2019.

Comparative genomic analyses of multi-drug resistant Mycobacterium tuberculosis from Nepal and other geographical locations.

Nepal exhibits a tuberculosis (TB) incidence rate that is comparable to neighbouring high TB incidence countries. In addition, it records >500 cases of multi-drug resistant (MDR) TB each year. The objective of this study was to perform whole-genome bioinformatic analysis on MDR-TB isolates from Nepal (n = 19) to identify the specific mutations underlying their phenotypic resistance.

Diagnostic performance of GeneXpert MTB/RIF assay compared to conventional culture for diagnosis of pulmonary and extrapulmonary tuberculosis, Nepal.

Tuberculosis is an infectious disease caused by the . It is a global health problem and major cause of death in resource-limited countries like Nepal. Timely diagnosis with sensitive testing methods could assist in early management of the disease.

Potent HCV NS3 Protease Inhibition by a Water-Soluble Phyllanthin Congener.

NS3/4A protease of hepatitis C virus (HCV) plays an important role in viral RNA replication. A 1,4-diphenylbutanedicarboxylic acid derivative, namely, phyllanthin, extracted from the leaf of a herbal plant, inhibits HCV NS3/4A protease and replication activities. However, the reduced aqueous solubility, high toxicity, and poor oral bioavailability are major impediments with phyllanthin.

Tetrazolylpyrene unnatural nucleoside as a human telomeric multimeric G-quadruplex selective switch-on fluorescent sensor.

We report herein the specific sensing of dimeric H45 G-quadruplex DNA via a fluorescence light-up response using fluorescent tetrazolylpyrene nucleoside (B) as a probe. The strong binding of the probe via an intercalative stacking interaction inside the connecting loop of two G-quadruplex units of H45 and the discrimination to other monomeric and long DNA duplexes are accompanied by a drastic enhancement of the emission intensity without compromising the conformation and stability.

Isolation, speciation and antifungal susceptibility testing of Candida isolates from various clinical specimens at a tertiary care hospital, Nepal.

Background: Candida species are responsible for various clinical infections ranging from mucocutaneous infection to life threatening invasive diseases along with increased resistance to antifungal drugs has made a serious concern. Resistance to antifungal agents has increased during the last decade. Thus, identification of Candida up to species level and its antifungal susceptibility testing has a paramount significance in the management of Candidal infections.

Trifunctional fluorescent unnatural nucleoside: Label free detection of T-T/C-C base mismatches, abasic site and bulge DNA.

The detection and targeting of both the mismatched and abasic DNA is highly important which would ultimately help in designing new diagnostics and chemotherapeutics. Furthermore, sensing and targeting the bulge sequence with a fluorescent probe would be useful to study the role of bulges in nucleic acid function or could have significant therapeutic potential. Thus, detection of specific bulges by small fluorescent molecules is an attractive research area since the past several years.

Hybridization accompanying FRET event in labeled natural nucleoside-unnatural nucleoside containing chimeric DNA duplexes.

Förster resonance energy transfer (FRET) is a highly efficient strategy in illuminating the structures, structural changes and dynamics of DNA, proteins and other biomolecules and thus is being widely utilized in studying such phenomena, in designing molecular/biomolecular probes for monitoring the hybridization event of two single stranded DNA to form duplex, in gene detection and in many other sensory applications in chemistry, biology and material sciences. Moreover, FRET can give information about the positional status of chromophores within the associated biomolecules with much more accuracy than other methods can yield. Toward this end, we want to report here the ability of fluorescent unnatural nucleoside, triazolylphenanthrene ((TPhen)BDo) to show FRET interaction upon hybridization with fluorescently labeled natural nucleosides, (Per)U or (OxoPy)U or (Per)U, forming two stable chimeric DNA duplexes.

Synthesis, photophysical properties of triazolyl-donor/acceptor chromophores decorated unnatural amino acids: Incorporation of a pair into Leu-enkephalin peptide and application of triazolylperylene amino acid in sensing BSA.

The research in the field of design and synthesis of unnatural amino acids is growing at a fast space for the increasing demand of proteins of potential therapeutics and many other diversified novel functional applications. Thus, we report herein the design and synthesis of microenvironment sensitive fluorescent triazolyl unnatural amino acids (UNAA) decorated with donor and/or acceptor aromatic chromophores via click chemistry. The synthesized fluorescent amino acids show interesting solvatochromic characteristic and/or intramolecular charge transfer (ICT) feature as is revealed from the UV-visible, fluorescence photophysical properties and DFT/TDDFT calculation.

Donor/acceptor chromophores-decorated triazolyl unnatural nucleosides: synthesis, photophysical properties and study of interaction with BSA.

Much effort has been put forth to develop unnatural, stable, hydrophobic base pairs with orthogonal recognition properties and study their effect on DNA duplex stabilisation. Our continuous efforts on the design of fluorescent unnatural biomolecular building blocks lead us to the synthesis of some triazolyl donor/acceptor unnatural nucleosides via an azide-alkyne 1,3-dipolar cycloaddition reaction as a key step, which we want to report herein. We have studied their photophysical properties and found interesting solvatochromic fluorescence for two of the nucleosides.

Wavelength shifting oligonucleotide probe for the detection of adenosine of a target DNA with enhanced fluorescence signal.

The modulated photophysical property of strong electronically coupled naphthyl uridine linked via a single C-C bond was explored in DNA detection via wavelength shifting and enhanced fluorescence emission by a simple 'Just-Mix & Read' strategy of homogeneous DNA detection.

Highly solvatochromic fluorescent naphthalimides: design, synthesis, photophysical properties and fluorescence switch-on sensing of ct-DNA.

We report the design, synthesis and photophysical properties of highly solvatochromic donor/acceptor substituted naphthalimide based fluorophores. The synthesized naphthalimides containing propargyl ends showed highly solvatochromic intramolecular charge transfer (ICT) feature as was revealed from the UV-visible, fluorescence photophysical properties of these fluorophores and DFT/TDDFT calculation. Fluorescence life times for the imide fluorophores were also measured in different solvents.

Photosynthetic response of clusterbean chloroplasts to UV-B radiation: energy imbalance and loss in redox homeostasis between Q(A) and Q(B) of photosystem II.

The effects of ultraviolet-B (UV-B: 280-320 nm) radiation on the photosynthetic pigments, primary photochemical reactions of thylakoids and the rate of carbon assimilation (P(n)) in the cotyledons of clusterbean (Cyamopsis tetragonoloba) seedlings have been examined. The radiation induces an imbalance between the energy absorbed through the photophysical process of photosystem (PS) II and the energy consumed for carbon assimilation. Decline in the primary photochemistry of PS II induced by UV-B in the background of relatively stable P(n), has been implicated in the creation of the energy imbalance(.