Publications by authors named "Philip Stewart"

Aim: Immune dysregulation and delayed onset of sleep wake cycling (SWC) are associated with worse outcome in neonatal encephalopathy (NE), however the association between sleep and immune dysfunction in NE remains unclear. Aimed to evaluate association of sleep and systemic inflammation with outcomes in NE.

Methods: Amplitude-integrated electroencephalography (aEEG) recordings were collected on infants undergoing therapeutic hypothermia (TH).

View Article and Find Full Text PDF

The present minireview aims to provide a context for imagination of the timespan for bone infection evolution from the origin of cellular bone tissue to modern orthopedic surgery. From a phylogenetic osteomyelitis-bracketing perspective, and due to the time of osteocyte origin, bacteria might have been able to infect the skeleton for approximately 400 million years. Thereby, bone infections happened simultaneously with central expansions of the immune system and development of terrestrial bone structure.

View Article and Find Full Text PDF

() is the leading cause of surgical site infections (SSIs) and is capable of biofilm growth on implanted foreign devices. The use of surgical irrigation solutions has become a common strategy to combat bacterial contamination events that occur during surgery. Despite their antimicrobial activity, SSI rates remain consistent, suggesting that low-level contamination persists.

View Article and Find Full Text PDF

The presence of microbial biofilms in many human chronic wounds led to the hypothesis that biofilms delay healing of these wounds. We tested this hypothesis in a population of 117 older individuals with venous leg ulcers who were receiving standardised therapy, including frequent debridement. Debridement specimens were analysed for the amount of bacterial biomass by two independent methods: a microscopic approach that scored the relative size and number of bacterial aggregates, interpreted as a biofilm metric, and conventional enumeration by agar plating for viable bacteria.

View Article and Find Full Text PDF
Article Synopsis
  • - Neonatal encephalopathy (NE) leads to multiorgan injury in newborns, with therapeutic hypothermia being the common treatment; this study aims to identify effective scoring systems for assessing organ dysfunction in NE.
  • - A systematic review of 628 articles was conducted, identifying 12 relevant studies, which showed a correlation between the severity of NE and multiorgan dysfunction, but highlighted significant differences across scoring systems used.
  • - For a comprehensive scoring system, the study suggests including assessments of various organ systems (renal, hepatic, respiratory, neurological, hematological, and cardiovascular), while noting that further validation and standardization are necessary for effective use, especially considering the impact of therapeutic hypothermia.
View Article and Find Full Text PDF

Aim: Retinopathy of prematurity is a significant global cause of childhood blindness. This study aims to identify serum biomarkers that are associated with the development of ROP.

Methods: A systematic review and meta-analysis was conducted using PRISMA guidelines.

View Article and Find Full Text PDF
Article Synopsis
  • This study aimed to analyze wound-related factors (like biofilm and bacteria), symptoms (such as pain and swelling), and systemic inflammation (specifically serum CRP levels) in older patients with chronic venous leg ulcers over an 8-week treatment period.
  • A total of 117 participants received standardized care, and data were collected bi-weekly to evaluate the relationships among these factors using a Bayesian statistical approach.
  • Results indicated a strong link between biofilm presence and total bacteria, as well as moderate connections between biofilm and inflammation (CRP levels) and symptoms (like pain and exudate), emphasizing the need to assess and manage both wound-related factors and systemic inflammation for effective treatment.
View Article and Find Full Text PDF
Article Synopsis
  • Tick-borne flaviviruses (TBFV) get transmitted when an infected tick bites and eats infected blood.
  • Researchers studied the midgut of ticks, which is important for understanding how TBFV spreads, using live tick cells in the lab.
  • They found that when ticks were infected with the Langat virus, the virus multiplied a lot, particularly in special cells in the midgut called generative cells.
View Article and Find Full Text PDF

Objectives: Long-term follow-up of patients treated with trastuzumab largely focuses on those with reduced left ventricular ejection fraction (LVEF) on treatment completion. This study sought to evaluate the prevalence of cardiovascular risk factors, overt cardiovascular disease and cardiac imaging abnormalities using cardiac magnetic resonance (CMR), in participants with normal LVEF on completion of trastuzumab±anthracycline therapy at least 5 years previously.

Methods: Participants with human epidermal growth factor receptor 2-positive breast cancer treated with trastuzumab±anthracycline ≥5 years previously were identified from a clinical database.

View Article and Find Full Text PDF

Bacterial biofilms account for up to 80% of all infections and complicate successful therapies due to their intrinsic tolerance to antibiotics. Biofilms also cause serious problems in the industrial sectors, for instance due to the deterioration of metals or microbial contamination of products. Efforts are put in finding novel strategies in both avoiding and fighting biofilms.

View Article and Find Full Text PDF

Hydrogen peroxide (HP) is a common disinfectant and antiseptic. When applied to a biofilm, it may be expected that the top layer of the biofilm would be killed by HP, the HP would penetrate further, and eventually eradicate the entire biofilm. However, using the Biofilm.

View Article and Find Full Text PDF

Powassan infection is caused by two closely related, tick-transmitted viruses of the genus (family ): Powassan virus lineage I (POWV) and lineage II (known as deer tick virus [DTV]). Infection is typically asymptomatic or mild but can progress to neuroinvasive disease. Approximately 10% of neuroinvasive cases are fatal, and half of the survivors experience long-term neurological sequelae.

View Article and Find Full Text PDF

Synthetic biology has shown remarkable potential to program living microorganisms for applications. However, a notable discrepancy exists between the current engineering practice-which focuses predominantly on planktonic cells-and the ubiquitous observation of microbes in nature that constantly alternate their lifestyles on environmental variations. Here we present the de novo construction of a synthetic genetic program that regulates bacterial life cycle and enables phase-specific gene expression.

View Article and Find Full Text PDF

The relapsing fever agent Borrelia hermsii is transmitted by the tick Ornithodoros hermsi. To study the B. hermsii-tick interactions required for pathogen acquisition and transmission we developed an artificial membrane feeding system for O.

View Article and Find Full Text PDF

Bacterial biofilms are often defined as communities of surface-attached bacteria and are typically depicted with a classic mushroom-shaped structure characteristic of Pseudomonas aeruginosa. However, it has become evident that this is not how all biofilms develop, especially in vivo, in clinical and industrial settings, and in the environment, where biofilms often are observed as non-surface-attached aggregates. In this Review, we describe the origin of the current five-step biofilm development model and why it fails to capture many aspects of bacterial biofilm physiology.

View Article and Find Full Text PDF
Article Synopsis
  • A study examined antibiotic tolerance in biofilms formed by three bacterial species (Pseudomonas aeruginosa, Staphylococcus aureus, and Acinetobacter baumannii) using transcriptomic and metabolomic approaches, finding no universal genetic defense mechanism.
  • Although all species showed reduced antibiotic susceptibility when in biofilm form compared to free-floating (planktonic) cells, no common gene or metabolic pathway related to this tolerance was identified across the different bacteria.
  • The research highlighted species-specific metabolic changes, like increased glucose consumption and decreased utilization of certain amino acids in biofilms, indicating that tolerance mechanisms are complex and varied among different types of bacteria rather than being universally programmed.
View Article and Find Full Text PDF

The goal of this study was to quantify the variability of confocal laser scanning microscopy (CLSM) time-lapse images of early colonizing biofilms to aid in the design of future imaging experiments. To accomplish this a large imaging dataset consisting of 16 independent CLSM microscopy experiments was leveraged. These experiments were designed to study interactions between human neutrophils and single cells or aggregates of () during the initial stages of biofilm formation.

View Article and Find Full Text PDF

Blood-feeding arthropods support a diverse array of symbiotic microbes, some of which facilitate host growth and development whereas others are detrimental to vector-borne pathogens. We found a common core constituency among the microbiota of 16 different arthropod blood-sucking disease vectors, including , , , , , , and . By comparing 21 genomes of common bacterial symbionts in blood-feeding vectors versus non-blooding insects, we found that certain enteric bacteria benefit their hosts by upregulating numerous genes coding for essential nutrients.

View Article and Find Full Text PDF

Borrelia burgdorferi, the causative agent of Lyme disease, has a complex and segmented genome consisting of a small linear chromosome and up to 21 linear and circular plasmids. Some of these plasmids are essential as they carry genes that are critical during the life cycle of the Lyme disease spirochete. Among these is a highly conserved linear plasmid, lp54, which is crucial for the mouse-tick infectious cycle of B.

View Article and Find Full Text PDF

Standard doses of antibiotics do not efficiently treat chronic infections of the soft tissue and bone. In this Personal View, we advocate for improving treatment of these infections by taking the infectious microenvironment into account. The infectious microenvironment can cause sensitive bacteria to lose their susceptibility to antibiotics that are effective in standard laboratory susceptibility testing.

View Article and Find Full Text PDF

The synthesis and biological activity of several novel nitrothiazole, nitrobenzothiazole, and nitrofuran containing antimicrobial agents for the eradication of biofilm-forming Gram-negative and Gram-positive pathogens is described. Nitazoxanide (NTZ), nitrofurantoin, and furazolidone are commercial antimicrobials which were used as models to show how structural modification improved activity toward planktonic bacteria via minimum inhibitory concentration (MIC) assays and biofilms via minimum biofilm eradication concentration (MBEC) assays. Structure-activity relationship (SAR) studies illustrate the ways in which improvements have been made to the aforementioned antimicrobial agents.

View Article and Find Full Text PDF

Biofilms that form on implanted medical devices cause recalcitrant infections. The early events enabling contaminating bacteria to evade immune clearance, before a mature biofilm is established, are poorly understood. Live imaging in vitro demonstrated that Staphylococcus aureus sparsely inoculated on an abiotic surface can go undiscovered by human neutrophils, grow, and form aggregates.

View Article and Find Full Text PDF

Background: Cerebral palsy (CP) is a heterogeneous group of non-progressive disorders of posture or movement, caused by a lesion of the developing brain. Osteoporosis is common in children with cerebral palsy, particularly in children with reduced gross motor function, and leads to an increased risk of fractures. Gross motor function in children with CP can be categorised using a tool called the Gross Motor Function Classification System (GMFCS).

View Article and Find Full Text PDF

Research on biofilms is predominantly made in in vitro contexts. However, in vivo observation of biofilms in human chronic infections shows distinct differences compared to in vitro biofilm growth. This could imply the use of an inadequate mental model both in research and healthcare practices.

View Article and Find Full Text PDF