Number Of Multidrug-resistant Bacteria Research Articles

The Retaining Pse5Ac7Ac Pseudaminyltransferase KpsS1 Defines a Previously Unreported glycosyltransferase family (GT118).

Cell surface sugar 5,7-diacetyl pseudaminic acid (Pse5Ac7Ac) is a bacterial analogue of the ubiquitous sialic acid, Neu5Ac, and contributes to the virulence of a number of multidrug resistant bacteria, including ESKAPE pathogens Pseudomonas aeruginosa, and Acinetobacter baumannii. Despite its discovery in the surface glycans of bacteria over thirty years ago, to date no glycosyltransferase enzymes (GTs) dedicated to the synthesis of a pseudaminic acid glycosidic linkage have been unequivocally characterised in vitro. Herein we demonstrate that A. baumannii KpsS1 is a dedicated pseudaminyltransferase enzyme (PseT) which constructs a Pse5Ac7Ac-α(2,6)-Glcp linkage, and proceeds with retention of anomeric configuration. We utilise this PseT activity in tandem with the biosynthetic enzymes required for CMP-Pse5Ac7Ac assembly, in a two-pot, seven enzyme synthesis of an α-linked Pse5Ac7Ac glycoside. Due to its unique activity and protein sequence, we also assign KpsS1 as the prototypical member of a previously unreported GT family (GT118).

The Retaining Pse5Ac7Ac Pseudaminyltransferase KpsS1 Defines a Previously Unreported glycosyltransferase family (GT118)

AbstractCell surface sugar 5,7‐diacetyl pseudaminic acid (Pse5Ac7Ac) is a bacterial analogue of the ubiquitous sialic acid, Neu5Ac, and contributes to the virulence of a number of multidrug resistant bacteria, including ESKAPE pathogens Pseudomonas aeruginosa, and Acinetobacter baumannii. Despite its discovery in the surface glycans of bacteria over thirty years ago, to date no glycosyltransferase enzymes (GTs) dedicated to the synthesis of a pseudaminic acid glycosidic linkage have been unequivocally characterised in vitro. Herein we demonstrate that A. baumannii KpsS1 is a dedicated pseudaminyltransferase enzyme (PseT) which constructs a Pse5Ac7Ac‐α(2,6)‐Glcp linkage, and proceeds with retention of anomeric configuration. We utilise this PseT activity in tandem with the biosynthetic enzymes required for CMP‐Pse5Ac7Ac assembly, in a two‐pot, seven enzyme synthesis of an α‐linked Pse5Ac7Ac glycoside. Due to its unique activity and protein sequence, we also assign KpsS1 as the prototypical member of a previously unreported GT family (GT118).

Antimicrobial Resistance: Two-Component Regulatory Systems and Multidrug Efflux Pumps.

The number of multidrug-resistant bacteria is rapidly spreading worldwide. Among the various mechanisms determining resistance to antimicrobial agents, multidrug efflux pumps play a noteworthy role because they export extraneous and noxious substrates from the inside to the outside environment of the bacterial cell contributing to multidrug resistance (MDR) and, consequently, to the failure of anti-infective therapies. The expression of multidrug efflux pumps can be under the control of transcriptional regulators and two-component systems (TCS). TCS are a major mechanism by which microorganisms sense and reply to external and/or intramembrane stimuli by coordinating the expression of genes involved not only in pathogenic pathways but also in antibiotic resistance. In this review, we describe the influence of TCS on multidrug efflux pump expression and activity in some Gram-negative and Gram-positive bacteria. Taking into account the strict correlation between TCS and multidrug efflux pumps, the development of drugs targeting TCS, alone or together with already discovered efflux pump inhibitors, may represent a beneficial strategy to contribute to the fight against growing antibiotic resistance.

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.

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. A descriptive cross-sectional study was carried out at a tertiary care centre from 8 August 2018 to 9 January 2019. Ethical approval was received from the Institutional Review Committee (Reference number: 123/2018). Clinically suspected cases of urinary tract infection were included in this study. A convenience sampling method was used. Point estimate and 95% Confidence Interval were calculated. Among 594 patients with urinary tract infections, the prevalence of multidrug resistant Escherichia coli was 102 (17.17%) (14.14-20.20, 95% Confidence Interval). Out of which, the production of extended-spectrum beta-lactamase and AmpC beta-lactamase were observed in 74 (72.54%), and 28 (27.45%) isolates respectively. The co-production of extended-spectrum beta-lactamases/AmpC was observed in 17 (16.67%). The prevalence of multidrug resistant Escherichia coli among patients urinary samples of patient with urinary tract infection was lower as compared to the other studies done in similar settings. antibiotics; Escherichia coli; urinary tract infection.

ACTIVITY OF CEC_KAZ_2018 BACTERIOPHAGE AGAINST E. COLI STRAINS CAUSING COLIBACILLOSIS IN CHICKENS

According to the European Food Safety Agency (EFSA) campylobacteriosis, salmonellosis and escherichiosis are major foodborne pathogens and, as a consequence, a serious public health problem. Due to the uncontrolled use of antibiotics as food additives, the poultry industry was one of the first faced the problem of spreading antibiotic resistance among bacterial pathogens. The emergence of multidrug-resistant infections and the ineffectiveness of antibiotics is one of the main problems of modern veterinary medicine. The gradual increase in the number of multidrug-resistant bacteria has led to an increase in research on the use of bacteriophages to combat bacterial infections. Phage therapy is a very promising direction, due to the high specificity of bacteriophages, their harmlessness and the ability to reproduce directly on the pathogen. Phage therapy is a very promising alternative approach, due to the high specificity of bacteriophages, their harmlessness and the ability to reproduce directly on the pathogen. In addition, bacteriophages are the most abundant organisms and their approximate number on Earth can reach 1031, which is more than 10 times the number of described species of bacteria and is an almost inexhaustible source for isolating new, more effective strains. In this study, the distribution of E. coli strains on poultry farms in the Almaty region were analyzed, as well as studied the morphology of the CEC_KAZ_2018 bacteriophage and its lytic properties in relation to newly isolated E. coli strains. From samples of internal organs of chickens with signs of colibacillosis, 15 cultures of Escherichia coli were isolated and identified. Analysis of the phylogenetic groups of isolates showed that the majority (73.4%) belonged to phylogroup D. It was revealed that up to 50% of the isolates showed resistance to antibiotics of the third generation: ceftazidime, aztreonam, and ceftazidime / clavulanate. Findings of the current study on the spectrum of lytic activity showed that the bacteriophage CEC_KAZ_2018 is able to lyse 10 out of 15 isolated cultures. Thus, this bacteriophage is a very promising candidate for the creation of antibacterial agents to combat colibacillosis in chickens.

Computational studies of membrane pore formation induced by Pin2

Understanding, at the molecular level, the effect of AMPs on biological membranes is of crucial importance given the increasing number of multidrug-resistant bacteria. Being part of an ancient type of innate immunity system, AMPs have emerged as a potential solution for which bacteria have not developed resistance. Traditional antibiotics specifically act on biosynthetic pathways, while AMPs may directly destabilize the lipid membrane, but it is unclear how AMPs affect the membrane’s stability. We performed multiscale molecular dynamics simulations to investigate the structural features leading to membrane pores formation on zwitterionic and anionic membranes by the antimicrobial peptide (AMP) Pandinin 2 (Pin2). Some experimental reports propose that Pin2 could form barrel-stave pores, while others suggest that it could form toroidal pores. Since there is no conclusive evidence of which type of pore is formed by Pin2 on bilayers, performing molecular dynamics simulations on these systems could shed some light on whether or not or what type of pore Pin2 forms on model membranes. Our results are focused on a detailed description of the pore formation by Pin2 in POPC and POPE:POPG membranes., which strongly suggest that Pin2 forms a toroidal pore and not a barrel-shaped pore; this type of pore also affects the membrane properties. In the process, a phospholipid remodeling in the POPE:POPG membrane takes place. Moreover, the pores formed by Pin2 indicate that they are selective for the chlorine ion. There are no previous ion selectivity reports for other AMPs with similar physicochemical properties, such as melittin and magainin. Communicated by Ramaswamy H. Sarma

Hospital Wastewater-Important Source of Multidrug Resistant Coliform Bacteria with ESBL-Production.

This work compares the prevalence of antibiotic resistant coliform bacteria in hospital wastewater effluents in Slovak (SR) and Czech Republic (ČR). It also describes selected antibiotic resistant isolates in view of resistance mechanism and virulence factor. The highest number of multidrug resistant bacteria was detected in samples from the hospital in Valašské Meziříčí (ČR). More than half of resistant isolates showed multidrug resistance phenotype as well as strong ability to form biofilm. In 42% of isolates efflux pump overproduction was detected together with tetA and tetE genes. The production of extended-spectrum β-lactamases in coliform isolates was encoded mainly by blaTEM, blaCTX-M-2 and blaCTX-M-8/25 genes. About 62% of resistants contained a combination of two or more extended spectrum beta-lactamases (ESBL) genes. Our results strengthen the fact that hospital effluents are a source of multidrug resistant bacteria which can spread their resistance genes to other bacteria in wastewater treatment plants (WWTPs). Accordingly, hospital wastewater should be better treated before it enters urban sewerage.

Comparative antibacterial potential of silver nanoparticles prepared via chemical and biological synthesis

New and improved approaches are urgently needed to fight the increasing number of multi-drug resistant bacteria. The antibacterial effect of silver nanoparticles (AgNPs) prepared by standardized chemical and biological syntheses is compered here. Biological systems included extracts of Opuntia ficus-indica mucilage and extracellular growth broth of Aspergillus niger and Bacillus megaterium. The nanoparticles were characterized by infrared spectroscopy, IR, and transmission electron microscopy. All of the AgNPs shared characteristic IR peaks and had an average size of 20–60 nm. The AgNPs were mainly spherical regardless of synthetic path. The synthesis based on the extracellular broth of the fungus, due to the highest biomass and active compounds concentration, resulted in a high yield of nanoparticle formation. These AgNPs also exhibited the highest inhibition zone against Salmonella typhimurium and Staphylococcus aureus. The syntheses reported here have no significant influence on AgNPs physical characteristics, as compared to literature, but represent processes with shorter reaction time. Additionally, the fungal based nanoparticles have superior antibacterial characteristics.

Aerobic Bacteriological Profile and Antimicrobial Sensitivity Pattern of Bacteria Isolated from Sterile Body Fluids: A Study from a Tertiary Care Hospital in North India

Aims: This study aims to isolate and identify the aerobic bacterial pathogens of sterile body fluids and to determine their susceptibility to various antibacterial agents.
 Study Design: This study was a retrospective observational study conducted in a tertiary care hospital.
 Place and Duration of Study: This study was conducted in the Department of Microbiology, SMHS hospital, Srinagar. A total of 814 samples were analysed for bacteriological culture and antibiotic sensitivity over a period of one year, from April 2018 to March 2019.
 Methodology: Clinical specimens (pleural fluid, ascitic fluid, cerebrospinal fluid, Synovial fluid, pericardial fluid and bile) were processed for bacterial culture according to standard procedures and antimicrobial susceptibility test for isolated organisms was done using Kirby Bauer disc diffusion method and interpreted as per Clinical and Laboratory Standards Institute (CLSI) recommendations.
 Results: In 814 samples of various body fluids, 88 samples showed growth of organism with an isolation rate of 10.81%. growth was most commonly seen in CSF (34.09%) followed by Ascitic fluid (23.86%, Bile (20.45), Pleural fluid (15.90%) and Synovial fluid (5.68%). No growth was obtained from pericardial fluid. The most predominant isolates were E. coli (23.86%), Pseudomonas sp (15.90%), Acinetobacter (14.77%), Klebsiella sp (7.95%), Staphylococcus aureus (11.36%), CONS (12.5%) and Enterococcus sp (4.54%). E. coli and Klebsiella were sensitive to imipenem, meropenem. colistin, amikacin and gentamicin. Staph. aureus and CONS were mostly sensitive to vancomycin, linezolid, and teicoplanin. Pseudomonas was sensitive to imipenem, meropenem, colistin and piperacillin/tazobactam. Acinetobacter, E. coli and Klebsiella sp were the most resistant organisms.
 Conclusion: In our study significant numbers of multidrug resistant bacteria were isolated from body fluids which calls for regular monitoring of prevalent pathogenic organisms and their sensitivities to avoid indiscriminate use of unnecessary antibiotics and the development of antibiotic resistance.

Time-Resolved Single-Cell Lysis Kinetics of Metal Nanoparticle-Infused Biopolymer Matrices

Bacterial infections continue to be a growing concern in healthcare facilities due to the increasing number of multi-drug resistant bacteria. The extensive use of antibiotics has weakened the potency and effectiveness of these drugs, consequently promoting bacterial infections and extending healing time. Therefore, there is an immediate demand to find an alternate method to combat the spread of bacterial infections. Metal nanoparticles (MNP) have proven to be an effective antibacterial agent against antibiotic-resistant bacteria, and when incorporated into polymeric substrates, have exhibited high toxicity towards bacterial cells. Current research proposes that MNP interact with the bacterial cell wall, undergo redox processes to form ions, and the ions diffuse into the cell resulting in disruption of membrane-bound proteins. This results in the inhibition of cell replication or cell lysis. However, existing methods of antimicrobial susceptibility testing, such as broth dilution assays and disk diffusion, fail to provide a greater understanding of the time scale required for the single cell lysis process to occur. More specifically, the conventional methods have substrate and agent limitations, as well as assume homogeneity in the bacterial population, therefore making the techniques an ineffective method for probing the cell lysis mechanism of MNP-infused biopolymer matrices. To further investigate the mechanistic action of metal nanocomposites, this research utilizes epi-fluorescence optical tweezers for antibacterial characterization. More specifically, a single E. coli cell was optically trapped, non-covalently docked to MNP-infused alginate matrix, and the cell viability kinetics were monitored in situ. Initial results showed that antibacterial activity of Cu and Ag functionalized nanocomposites was related to the metal concentration and size of colloidal NP. Ag incorporated polymers exhibited greater antibacterial effectiveness when compared to Cu potentially due to the role of Cu in cellular respiration processes. Results further indicate that the size of the MNP does impact the rate of single cell lysis, which may be related to the redox kinetics at the cell/MNP interface.

Mechanisms of Polymyxin Resistance.

Polymyxin antibiotics are increasingly being used as last-line therapeutic options against a number of multidrug resistant bacteria. These antibiotics show strong bactericidal activity against a range of Gram-negative bacteria, but with the increased use of these antibiotics resistant strains are emerging at an alarming rate. Furthermore, some Gram-negative species, such as Neisseria meningitidis, Proteus mirabilis and Burkholderia spp., are intrinsically resistant to the action of polymyxins. Most identified polymyxin resistance mechanisms in Gram-negative bacteria involve changes to the lipopolysaccharide (LPS) structure, as polymyxins initially interact with the negatively charged lipid A component of LPS. The controlled addition of positively charged residues such as 4-amino-L-arabinose, phosphoethanolamine and/or galactosamine to LPS results in a reduced negative charge on the bacterial surface and therefore reduced interaction between the polymyxin and the LPS. Polymyxin resistant species produce LPS that intrinsically contains one or more of these additions. While the genes necessary for most of these additions are chromosomally encoded, plasmid-borne phosphoethanolamine transferases (mcr-1 to mcr-8) have recently been identified and these plasmids threaten to increase the rate of dissemination of clinically relevant colistin resistance. Uniquely, Acinetobacter baumannii can also become highly resistant to polymyxins via spontaneous mutations in the lipid A biosynthesis genes lpxA, lpxC or lpxD such that they produce no LPS or lipid A. A range of other non-LPS-dependent polymyxin resistance mechanisms has also been identified in bacteria, but these generally result in only low levels of resistance. These include increased anionic capsular polysaccharide production in Klebsiella pneumoniae, expression of efflux systems such as MtrCDE in N. meningitidis, and altered expression of outer membrane proteins in a small number of species.

Exploring multiple effects of Zn0.15Mg0.85O nanoparticles on Bacillus subtilis and macrophages

The increasing number of multidrug resistant bacteria raises a serious public-health concern, which is exacerbated by the lack of new antibiotics. Metal oxide nanoparticles are already applied as an antibacterial additive in various products used in everyday life but their modes of action have remained unclear. Moreover, their potential negative effects to human health are still under evaluation. We explored effects of mixed metal oxide Zn0.15Mg0.85O on Bacillus subtilis, as a model bacterial organism, and on murine macrophages. Zn0.15Mg0.85O killed planktonic bacterial cells and prevented biofilm formation by causing membrane damages, oxidative stress and metal ions release. When exposed to a sub-inhibitory amount of Zn0.15Mg0.85O, B. subtilis up-regulates proteins involved in metal ions export, oxidative stress response and maintain of redox homeostasis. Moreover, expression profiles of proteins associated with information processing, metabolism, cell envelope and cell division were prominently changed. Multimode of action of Zn0.15Mg0.85O suggests that no single strategy may provide bacterial resistance. Macrophages tolerated Zn0.15Mg0.85O to some extend by both the primary phagocytosis of nanoparticles and the secondary phagocytosis of damaged cells. Bacterial co-treatment with ciprofloxacin and non-toxic amount of Zn0.15Mg0.85O increased antibiotic activity towards B. subtilis and E. coli.

Antimicrobial Resistance Phenotypic Profile of Isolates from Clinical Infections in Dogs

Background: Antimicrobial resistance is described as a condition in which a micro-organism is able to survive when exposed to an antimicrobial agent. The resistance rates to antimicrobials in companion animals have risen considerably. Studies of local antimicrobial susceptibility profiles are needed as well as education and warning about the use of tests for the identification and susceptibility of pathogenic bacterial strains. The aim of this study was to identify the main antimicrobial resistance in clinical samples of dogs, and to detect multidrug-resistant strains of importance to public health.Materials, Methods & Results: Bacterial pathogens of 77 dog infections were isolated and their sensitivity profile to antimicrobials was determined. One hundred bacterial isolates were identified. Of these, 61 were Gram-positive (55 Staphylococcus spp., 4 Enterococcus spp. and 2 Streptococcus spp.) and 39 Gram-negative (36 fermenters and 3 non-fermenters). Seventy-nine isolates were considered multiresistant following individual assessment of drugs, and 85 following the evaluation of classes. Only 3 were sensitive to all drugs. Four isolates were resistant to all classes and only sensitive to some antibiotics. Of the 55 samples of Staphylococcus spp., 36 (65.45%) were identified as phenotypically MRS. Two isolates of Enterococcus spp. were resistant to vancomycin (VRE). Also 66.67% (26/39) of the samples were positive for the presumptive test for ESBL. For the MRS-positive isolates detected in this study, chloramphenicol was the antimicrobial that showed superior sensitivity in 74.29% of the cases (27/36); therefore it is considered the most appropriate for treatment of this type of micro-organism. In case of aminoglycosides, when their resistance was checked in MRS isolates, all resistance percentages increased, implying a limited use of this class for such a type of multi-resistant micro-organism. Contrarily, in case of ESBL, a superior sensitivity was observed towards MRS isolates, thus making them a prime treatment choice for the infection caused by these micro-organisms.Discussion: Literature have reported a gradual increase in multidrug resistance towards antimicrobial agents in veterinary medicine over the past decades. In this study, 64% of multiresistant strains were considered of significant importance, notably MRS (36), VRE (2) and ESBL (26). The early identification of pathogens in animals has become an important step in order to minimize the transmission of antibacterial resistance. The increase in the number of multidrug-resistant bacteria in animals and humans demonstrates the need to develop and implement measures in order to monitor and control the spread of this resistance. It is possible that the increased drug resistance is linked to the constant exposure to these drugs and the subsequent selective pressure, causing the transfer of resistant genes between strains. Carbapenems and glycopeptides should be used with caution in veterinary medicine in order to prevent such processes of selection that develop resistance in micro-organisms to these two classes, which can result in cross-resistance between animals and humans and create obstacles in the treatment of patients, especially for the two drugs mentioned, since they are important for the treatment of nosocomial infections in humans. The resistance percentage towards fluoroquinolones was identified to be higher in Gram-positive isolates, particularly in MRS, which showed 75% resistance against this class (according to the CLSI, resistance to one fluoroquinolone antimicrobial agent provides resistance to other antimicrobials of this class). For ESBL isolates, the resistance was shown to be 50%. The resistance towards the fluoroquinolones and aminoglycosides class can be associated with the expression of the genes that produce ESBL.

Characterization of Anti-Biofilm Peptide Activity: A Biophysical Approach

The increasing number of multidrug resistant bacteria to available antibiotics is a growing problem worldwide. One major strategy for resistance and an important reason for failure of therapy in the clinic is biofilm formation. To cope with unfavorable surroundings many bacteria live as biofilms, sessile micro-colonies adherent to surfaces that secrete an extracellular polymeric substance. An attractive alternative to conventional antibiotics are antimicrobial peptides (AMPs), innate immune system molecules that target the bacterial cytoplasmic membrane, causing membrane disruption and cell death. AMPs biophysical properties are extensively studied regarding planktonic bacteria but much less so regarding biofilm formation. By designing and synthesizing a series of model peptides that share the same amino acids composition but differ in their biophysical properties, we investigated how different steps of biofilm formation are affected by the AMP's features. We modified the peptides characteristics using different approaches of charge segregation and amino acids D enantiomers. We used Pseudomonas aeruginosa, an opportunistic Gram-negative bacteria, which is a leading cause of severe pulmonary infections in cystic fibrosis patients and medical device contamination. Our work demonstrates that the peptides combat biofilm at different stages of its formation and maintenance: (1) killing bacteria at their planktonic stage (2) preventing bacterial adhesion to biomaterials and (3) degrading pre-formed biofilm. We show that substitution of L-to-D amino acids alters the peptides biophysical properties and improves their activity against each stage in the biofilm life cycle. By investigating which biophysical properties are essential for anti-biofilm activity we also discovered new mechanisms of peptides activity.

Identification of virulence factors and antibiotic resistance markers using bacterial genomics.

In recent years, the number of multidrug-resistant bacteria has increased rapidly and several epidemics were signaled in different regions of the world. Faced with this situation that presents a major global public health concern, the development and the use of new and rapid technologies is more than urgent. The use of the next-generation sequencing platforms by microbiologists and infectious disease specialists has allowed great progress in the medical field. Here, we review the usefulness of whole-genome sequencing for the detection of virulence and antibiotic resistance associated genes.

A New Evaluation Method for Antibiotic-Resistant Bacterial Groups in Environment

In the present manuscript it was presented whether spreading of antibiotic resistant bacterial groups in environment could be monitored by our newly developed method by enumerating antibiotic resistant bacterial groups in various biological wastes and composts. Although the numbers were not so high, diverse kinds of colistin resistant bacteria (25 mg·L-1) were included in row cattle feces (1.78 × 104 MPN g-1) and cattle feces manure (>3.84 × 104 MPN g-1). Compost originated from leftover food (>44.8 × 104 MPN g-1) and shochu lee (>320 × 104 MPN g-1) included higher numbers of chlortetracycline resistant Pseudomonas sp., (25 mg·L-1), and row cattle feces included higher numbers of chlortetracycline resistant Enterobacteriacea (15.7 × 104 MPN g-1), which mostly consisted from Pantoea sp. or Xenorhobdus doucetiae. Numbers of multi drug resistant bacteria, resistant to 25 mg·L-1 of ciprofloxacin, streptomycin, chloramphenicol, and ampicillin, were the highest in row cattle feces (>143.6 × 104 MPN g-1), followed by cattle feces manure (4.19 × 104 MPN g-1), and shochu lee (0.36 × 104 MPN g-1), which included diverse kinds of bacterial group. The present results indicated that higher numbers of multi drug resistant bacteria were typically found in row cattle feces, and the method was found suitable to enumerate and identify them. These results suggested that the method might become their environmental risk evaluation method.

Antibiotic Resistance of Bacterial Isolates from HIV Positive Patients with Urinary Tract Infection (UTI) in Portharcourt, Nigeria

This study was carried out to evaluate the prevalence of HIV associated Urinary tract infections (UTI) in Portharcourt Metropolis. 286 urine samples were collected from 246 HIV seropositive and 40 HIV seronegative individuals. Mid stream urine samples collected from these individuals were processed by standard protocols to examine for bacterial opportunistic pathogens. Antibiotic susceptibility testing was performed using Kirby-Bauer’s disc diffusion method. Out of 246 HIV individuals examined, 141 (57.3%) urine samples yielded growth of bacterial isolates, with age group 24-30 years recording the highest number of isolates 45 (32.9%), while those above 44 years old had the least with 11 (7.8%). About 24 (60%) samples out of 40 seronegative individuals yielded growth of bacteria and age group 17-23 years recorded the highest number of isolates 7 (29.1%), while those above 44 years had the least 1 (4.1%). Female individuals recorded the highest number of bacterial isolates than males. A total of 165 bacteria were identified and grouped into four genera out of which Staphylococcus aureus had the highest percentage of occurrence 49 (29.7%), followed by Escherichia coli 47 (28.5%), Pseudomonas aeruginosa 46 (27.9%) and Klebsiella pneumoniae 23 (13.9%). Out of 111 bacterial isolates that exhibited multidrug resistance, HIV Seropositive individuals had 103 (92.8%) and HIV seronegative individuals 8 (7.2%). Over all, Staphylococcus aureus recorded the highest number of multidrug resistant bacteria 36 (32.4%), followed by Pseudomonas aeruginosa 34 (30.6%). The high levels of multidrug resistance in HIV seropositive individuals are a serious public Health concern. Therefore appropriate health education to reduce selfmedication and drug abuse is very imperative and desirous.

Prevalence of multidrug resistant bacteria in causing community acquired urinary tract infection among the patients attending outpatient department of Seti Zonal Hospital, Dhangadi, Nepal

Involvement of multidrug resistant bacteria in causing community acquired infection is very serious public health issue. The main objective of our study was to determine the prevalence of multidrug resistant bacteria in causing community acquired urinary tract infection. In this study we cultured the 384 mid stream urine samples collected aseptically from the patients attending outpatient department of Seti zonal hospital and having no past history of hospitalization. The organisms isolated were identified by using conventional biochemical tests and antimicrobial susceptibility testing was performed by Kirby Bauer disc diffusion technique. Out of total 384 samples 98 (25.52%) samples showed significant bacterial growth. The most prevalent bacterium isolated was Escherichia coli. 42.86% of the bacteria isolated were found to be multidrug resistant (MDR). The involvement of such large numbers of multidrug resistant bacteria in causing community acquired urinary tract infection is very serious issue and cannot be neglected. And some abrupt initiatives should be taken by the responsible authorities to improve or at least avoid the further worsening of the situation.Nepal Journal of Biotechnology. Dec. 2015 Vol. 3, No. 1: 55-59

Want a better way to control antibiotic resistance? Fight the corruption

Want a better way to control antibiotic resistance? Fight the corruption

Silver nanoparticles do not alter human osteoclastogenesis but induce cellular uptake

Based on the increasing number of multi-drug resistant bacteria in periprosthetic infections, improvement of the antibacterial activity of commonly used biomaterials must be achieved. The broad-spectrum, high antimicrobial efficacy has made silver nanoparticles a promising new antibacterial agent. However, there is still a serious lack of knowledge concerning the impact of nanosilver on bone cells.For this reason a study was conducted to evaluate the influence of silver nanoparticles on osteoclastogenesis of human peripheral blood mononuclear cells. Upon incubation with subtoxic concentrations of nanosilver the cells did not exhibit changes in osteoclast differentiation and podosomal structures. However, the osteoclasts were able to uptake the nanoparticles, accumulating them in endo-lysosomal compartments. Furthermore, nanosilver exposure led to an increase in oxidative stress and a decrease in clathrin-dependent endocytosis on the mRNA level.In conclusion, our results indicate nanosilver-induced cell stress at higher concentrations. For this reason antibacterial benefits and possible health risks should be weighed in more detail in further studies.