Glucose-Induced Enhanced Virulence in Strains of Multidrug-Resistant Pseudomonas aeruginosa Isolated from Diabetic Patients.

Pseudomonas aeruginosa is known for its metabolic versatility and uses a variety of substrates; interestingly, glucose is not the favored carbon source. Although glucose is not readily utilized by them, there is a possibility that the increased susceptibility of diabetics to infections with P. aeruginosa is related to the effect of glucose on the expression of virulence genes. The curiosity in understanding the effect of glucose on virulence gene expression in P. aeruginosa and the lacuna of studies in this field prompted us to undertake the current investigation. It included the quantification of various virulence factors and their gene expression upon supplementation with glucose in clinical MDR P. aeruginosa isolates recovered from diabetics. Interestingly, the study observed a remarkable difference in the virulence attributes in the isolates with and without glucose supplementation. External glucose was found to be modulating the QS gene expression, thus altering the elaboration of other virulence factors. Variations in the gene expressions induced by glucose partly explain the increased susceptibility of diabetic patients to P. aeruginosa infections.

A rare occurrence of multidrug-resistant environmental Acinetobacter baumannii strains from the soil of Mangaluru, India.

Over the last decade, Acinetobacter baumannii has emerged as one of the main causes of infections acquired in the hospital setting. Outbreaks associated with this pathogen are caused mainly due to contamination and transmission in hospital territories. However, the natural habitats of A. baumannii of clinical significance still remain unclear. In this study, we highlight the isolation and identification of multidrug-resistant environmental strains of A. baumannii from the soil of Mangaluru city. All the recovered isolates were biofilm formers, and two isolates were multidrug-resistant and showed resistance to fluoroquinolone, aminoglycosides, sulfonamide, tetracycline, and carbapenems. In addition, they exhibited protease activity, and produced phospholipase C and siderophore. To the best of our knowledge, this is the first study to isolate and identify drug-resistant strains of A. baumannii from the soil.

Modulation of quorum sensing-associated virulence in bacteria: carbohydrate as a key factor.

Quorum sensing (QS) is a method of inter-cellular communication that permits bacteria to dispense information about cell density and to synchronize the gene expression accordingly. Gram-positive and Gram-negative bacteria utilize distinct quorum sensing mechanisms for effective pathogenesis. Virulence factor production by pathogenic bacteria is one of the important traits that is under the control of QS. A growing body of evidence has indicated the role of the nutritional environment notably by carbohydrates in dictating the QS-associated virulence gene regulation. The modulation of QS by carbohydrates mitigates the survival and establishment of the pathogen within its host which in turn leads to an increase in morbidity and mortality. This mini-review throws light on the predilection of pathogenic bacteria to rapidly regulate its QS-linked virulence gene expression based on the changing nutrient levels that assist them in prospering within diverse niches.

Global epidemiology of nonpolio enteroviruses causing severe neurological complications: A systematic review and meta-analysis.

Enteroviruses are RNA viruses found as commensals in the human gut and respiratory system, which may cause a wide spectrum of disease. Enteroviruses may cause severe neurologic complications including acute flaccid paralysis (AFP) and encephalitis and are the most commonly diagnosed agents of viral meningitis. Outbreaks of more severe disease are often associated with particular genotypes, such as enterovirus-A71 causing rhombencephalitis and AFP. There are more than 300 described genotypes of human enterovirus, with overlaps in clinical phenotypes between genotypes, and uncertainty about which genotypes are more prevalent in neurological manifestations. A systematic review of observational studies was conducted to evaluate the most prevalent enterovirus genotypes causing AFP, encephalitis, and meningitis. The genotyping methods and sampling sites were compiled as secondary outcomes. Sources included MEDLINE, Embase (publications until January 2019), and references selected from included studies. Meta-analyses using a random effects model were performed to calculate the pooled proportion of enterovirus genotypes in each disease. Ninety-six publications met the eligibility criteria, comprising 3779 AFP cases, 1140 encephalitis cases, and 32 810 meningitis cases. Enterovirus-A71 was most frequently associated with AFP (pooled proportion 0.12, 95% CI, 0.05-0.20) and encephalitis (0.77, 95% CI, 0.61-0.91). Echovirus 30 (0.35, 95% CI, 0.27-0.42) was the most predominant genotype in meningitis cases. Genotypes were most commonly determined using VP1 RT- reverse transcription-polymerase chain reaction, and most samples assessed were cerebrospinal fluid. With the emergence of enteroviruses as an increasing cause of neurological diseases, surveillance and testing need to increase to identify the aetiology of the most common and most severe disorders.

Comparison of Antibiofilm Activity of Pseudomonas aeruginosa Phages on Isolates from Wounds of Diabetic and Non-Diabetic Patients.

The persistence of organisms as biofilms and the increase in antimicrobial resistance has raised the need for alternative strategies. The study objective was to compare the ability of isolated bacteriophages to remove in vitro biofilms formed by Pseudomonas aeruginosa isolated from the environment with those isolated from diabetic and non-diabetic wounds. P. aeruginosa were isolated from clinical and environmental sites, and antimicrobial susceptibility was tested. Bacteriophages were isolated and characterized based on plaque morphology and host range. A reduction in the viable count assayed the lytic ability of candidate phages. The crystal violet method was used to determine the residual biofilm after 24 h of phage treatment on 72-h-old biofilms. The statistical significance of phage treatment was tested by one-way ANOVA. Of 35 clinical isolates, 17 showed resistance to 1 antibiotic at least, and 7 were multidrug resistant. Nineteen environmental isolates and 11 clinical isolates were drug-sensitive. Nine phages showed 91.2% host coverage, including multidrug-resistant isolates. Phages eradicated 85% of biofilms formed by environmental isolates compared to 58% of biofilms of diabetic isolates and 56% of biofilms of non-diabetic isolates. Clinical isolates are susceptible to phage infection in planktonic form. Biofilms of P. aeruginosa isolated from diabetic wounds and non-diabetic wounds resist removal by phages compared to biofilms formed by environmental isolates. All phages were efficient in dispersing PAO1 biofilms. However, there was a significant difference in their ability to disperse PAO1 biofilms across the different surfaces tested. Partial eradication of biofilm by phages can aid in complementing antibiotics that are unable to penetrate biofilms in a clinical set-up.

Advance care and resuscitation plans in a tertiary hospital: a multimodal approach.

OBJECTIVES: Advance care planning (ACP) is the process of documenting a person's preference for medical treatment in the event of future deterioration. This audit aimed to improve discussion and documentation of ACP in patients who die during a hospital admission. METHODS: We performed a clinical audit in 2021 of inpatients at a tertiary hospital in Sydney, Australia to evaluate the benefit of multimodal interventions to improve ACP compared with previous audits from 2016 and 2011. RESULTS: In 2021, 97% of audited patients had a documented ACP prior to death compared with 80% in the 2016 audit. The completion of NFR documentation on admission in 2016 was 33%, while in 2021 65% of ACPs were completed within 24 hours of admission.In 2021, 94% of patients had a paper resuscitation form filled; however, identification stickers, which are associated with risk of error, were used in 64%; and 25% of forms were only partially completed. Palliative care was consulted for 44% of patients prior to death; 33% on the day of or prior to death. CONCLUSIONS: Improvement in prevalence and timing of ACP prior to death is seen in the postintervention audit. A repeat audit in 5 years will be conducted, with interventions focused on improving documentation of ACP.

Isolation and identification of quorum sensing antagonist from Cinnamomum verum leaves against Pseudomonas aeruginosa.

PURPOSE: The study aimed at isolating and identifying potential anti-quorum sensing (QS) compounds from Cinnamomum verum leaves against Pseudomonas aeruginosa. METHODOLOGY: Isolation of anti-QS compounds from C. verum leaf ethanol extract was carried out by column chromatography. The bioactive fraction was analysed by UV, IR, and GCMS spectroscopy. Various virulence assays were performed to assess the QS quenching ability of the purified compounds. In vivo toxicity of the purified compounds was examined in zebrafish model. The expression of the virulence genes was evaluated by qPCR analysis and in silico assessment was accomplished to check the binding ability of the compounds with the autoinducer molecule. KEY FINDINGS: The QS inhibitors isolated and identified showed a remarkable ability in reducing the production of elastase, pyocyanin, swarming motility and biofilm formation in P. aeruginosa. In the presence of the characterized compounds, the expression of virulence genes of P. aeruginosa was significantly reduced. Toxicity studies in zebrafish model indicated no effects on development and organogenesis at a concentration below 100 mg/l. Further, in silico analysis demonstrated the binding efficiency of the anti-QS compounds to AHL molecules, thus proving the QS quenching ability of the isolated compounds. SIGNIFICANCE: To the best of our knowledge this is the first report of isolation of anti-QS compounds from C. verum leaves against P. aeruginosa. The identified compounds qualify as potential QS antagonists. Further studies on these compounds can pave way for an effective and attractive anti-pathogenic therapy, to overcome the emergence of antibiotic resistance in bacteria.

Australian medical student expectations of work-life balance as a doctor.

This article was migrated. The article was marked as recommended. Objectives: To explore the perceptions of medical students on achieving good work-life balance after graduation, and their opinions on parenting having an impact on their future careers. Methods: Cross-sectional cohort study of an online survey was distributed to students from all medical schools in Australia through the General Practice Students Network. Main outcome measures: Medical student perceptions on the effects of their future careers on the ability to maintain work-life balance and whether future parenting would impact their careers. Both quantitative and qualitative responses were collected. Results:The majority of survey respondents believed their careers would have a moderate or significant impact on the ability to achieve work-life balance. Thematic analysis revealed medical students perceived medical careers as lacking flexibility, being time-consuming, and potentially detrimental to health. Surveyed students indicated both parenting goals and specialty choice needed to be considered when planning their career. Conclusions: Australian medical students expressed significant concerns about their ability to juggle parenting and achieve work-life balance within the realities of a medical career.