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1.
J Chemother ; 36(2): 119-126, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37942621

ABSTRACT

We evaluated the effectiveness and safety of continuous antimicrobial infusion using a disposable elastomeric device in an outpatient parenteral antimicrobial therapy (OPAT) setting. We conducted a retrospective analysis of all patients who received either flucloxacillin (n = 131 episodes) or piperacillin/tazobactam (n = 301 episodes) as continuous infusion via elastomeric devices over 5 years (January 2018-December 2022) at a tertiary referral hospital in Derbyshire, UK. Overall, 81 adverse events were recorded in 77 (18%; 77/432) patient-episodes. Most adverse events were vascular access-related (59%; 4.6 events per 1000 OPAT-days), including one line-related infection (0.2%; 0.1 events per 1000 OPAT-days). 165 (38%) patient-episodes experienced at least one incident of incomplete infusion. Successful outcome (cure or improvement) occurred in 364 (84%) episodes. Our findings suggest that elastomeric infusion pumps are safe and effective for administering selected antimicrobial agents in OPAT. However, close monitoring of patients and the device are essential to ensure optimal delivery of prescribed therapy.


Subject(s)
Anti-Bacterial Agents , Anti-Infective Agents , Humans , Anti-Bacterial Agents/therapeutic use , Outpatients , Retrospective Studies , Infusion Pumps , United Kingdom , Ambulatory Care , Infusions, Parenteral
2.
NPJ Digit Med ; 6(1): 239, 2023 Dec 22.
Article in English | MEDLINE | ID: mdl-38135699

ABSTRACT

Previous studies have associated COVID-19 symptoms severity with levels of physical activity. We therefore investigated longitudinal trajectories of COVID-19 symptoms in a cohort of healthcare workers (HCWs) with non-hospitalised COVID-19 and their real-world physical activity. 121 HCWs with a history of COVID-19 infection who had symptoms monitored through at least two research clinic visits, and via smartphone were examined. HCWs with a compatible smartphone were provided with an Apple Watch Series 4 and were asked to install the MyHeart Counts Study App to collect COVID-19 symptom data and multiple physical activity parameters. Unsupervised classification analysis of symptoms identified two trajectory patterns of long and short symptom duration. The prevalence for longitudinal persistence of any COVID-19 symptom was 36% with fatigue and loss of smell being the two most prevalent individual symptom trajectories (24.8% and 21.5%, respectively). 8 physical activity features obtained via the MyHeart Counts App identified two groups of trajectories for high and low activity. Of these 8 parameters only 'distance moved walking or running' was associated with COVID-19 symptom trajectories. We report a high prevalence of long-term symptoms of COVID-19 in a non-hospitalised cohort of HCWs, a method to identify physical activity trends, and investigate their association. These data highlight the importance of tracking symptoms from onset to recovery even in non-hospitalised COVID-19 individuals. The increasing ease in collecting real-world physical activity data non-invasively from wearable devices provides opportunity to investigate the association of physical activity to symptoms of COVID-19 and other cardio-respiratory diseases.

3.
Int J Antimicrob Agents ; 62(3): 106911, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37422098

ABSTRACT

The risk of venous thromboembolism (VTE) in outpatient parenteral antimicrobial therapy (OPAT) is not fully understood and the optimal strategy for thromboprophylaxis remains unclear. This systematic review investigated the incidence of VTE in OPAT settings (PROSPERO CRD42022381523). MEDLINE, CINAHL, Emcare, Embase, Cochrane Library and grey literature were searched from earliest records to 18 January 2023. Primary studies reporting non-catheter-related VTE or catheter-related thromboembolism (CRT) events in adults who received parenteral antibiotics in home or outpatient settings were eligible. In total, 43 studies involving 23 432 patient episodes were reviewed, of which 4 studies reported non-catheter-related VTE and 39 included CRT. Based on generalised linear mixed-effects models, pooled risk estimates of non-catheter-related VTE and CRT were 0.2% [95% confidence interval (CI) 0.0-0.7%] and 1.1% [95% CI 0.8-1.5%; prediction interval (PI) 0.2-5.4%]. Heterogeneity was largely attributed to risk of bias by meta-regression (R2 = 21%). Excluding high-risk-of-bias studies, CRT risk was 0.8% (95% CI 0.5-1.2%; PI 0.1-4.5%). From 25 studies, the pooled CRT rate per 1000 catheter-days was 0.37 (95% CI 0.25-0.55; PI 0.08-1.64). These findings do not support universal thromboprophylaxis or routine use of an inpatient VTE risk assessment model in the OPAT setting. However, a high index of suspicion should be maintained, especially for patients with known risk factors for VTE. An optimised protocol of OPAT-specific VTE risk assessment should be sought.


Subject(s)
Anti-Infective Agents , Venous Thromboembolism , Adult , Humans , Venous Thromboembolism/drug therapy , Venous Thromboembolism/prevention & control , Venous Thromboembolism/epidemiology , Anticoagulants/therapeutic use , Outpatients , Risk Factors , Anti-Infective Agents/adverse effects
4.
Am J Respir Crit Care Med ; 207(8): 998-1011, 2023 04 15.
Article in English | MEDLINE | ID: mdl-36724365

ABSTRACT

Rationale: Chronic obstructive pulmonary disease (COPD) is a disease characterized by persistent airway inflammation and disordered macrophage function. The extent to which alterations in macrophage bioenergetics contribute to impaired antioxidant responses and disease pathogenesis has yet to be fully delineated. Objectives: Through the study of COPD alveolar macrophages (AMs) and peripheral monocyte-derived macrophages (MDMs), we sought to establish if intrinsic defects in core metabolic processes drive macrophage dysfunction and redox imbalance. Methods: AMs and MDMs from donors with COPD and healthy donors underwent functional, metabolic, and transcriptional profiling. Measurements and Main Results: We observed that AMs and MDMs from donors with COPD display a critical depletion in glycolytic- and mitochondrial respiration-derived energy reserves and an overreliance on glycolysis as a source for ATP, resulting in reduced energy status. Defects in oxidative metabolism extend to an impaired redox balance associated with defective expression of the NADPH-generating enzyme, ME1 (malic enzyme 1), a known target of the antioxidant transcription factor NRF2 (nuclear factor erythroid 2-related factor 2). Consequently, selective activation of NRF2 resets the COPD transcriptome, resulting in increased generation of TCA cycle intermediaries, improved energetic status, favorable redox balance, and recovery of macrophage function. Conclusions: In COPD, an inherent loss of metabolic plasticity leads to metabolic exhaustion and reduced redox capacity, which can be rescued by activation of the NRF2 pathway. Targeting these defects, via NRF2 augmentation, may therefore present an attractive therapeutic strategy for the treatment of the aberrant airway inflammation described in COPD.


Subject(s)
NF-E2-Related Factor 2 , Pulmonary Disease, Chronic Obstructive , Humans , Macrophages/metabolism , NF-E2-Related Factor 2/metabolism , Oxidative Stress , Pulmonary Disease, Chronic Obstructive/metabolism , Pulmonary Disease, Chronic Obstructive/physiopathology , Malate Dehydrogenase/metabolism
5.
Lancet Infect Dis ; 23(3): e115-e120, 2023 03.
Article in English | MEDLINE | ID: mdl-36470282

ABSTRACT

The 2022 monkeypox outbreak has affected 110 countries worldwide, outside of classic endemic areas (ie, west Africa and central Africa). On July 23, 2022, the outbreak was classified by WHO as a public health emergency of international concern. Clinical presentation varies from mild to life-changing symptoms; neurological complications are relatively uncommon and there are few therapeutic interventions for monkeypox disease. In this Grand Round, we present a case of monkeypox with encephalitis complicated by transverse myelitis in a previously healthy woman aged 35 years who made an almost complete recovery from her neurological symptoms after treatment with tecovirimat, cidofovir, steroids, and plasma exchange. We describe neurological complications associated with orthopoxvirus infections and laboratory diagnosis, the radiological features in this case, and discuss treatment options.


Subject(s)
Encephalitis , Mpox (monkeypox) , Myelitis, Transverse , Female , Humans , Africa, Western , Benzamides
6.
Lancet Infect Dis ; 23(5): 589-597, 2023 05.
Article in English | MEDLINE | ID: mdl-36566771

ABSTRACT

BACKGROUND: The scale of the 2022 global mpox (formerly known as monkeypox) outbreak has been unprecedented. In less than 6 months, non-endemic countries have reported more than 67 000 cases of a disease that had previously been rare outside of Africa. Mortality has been reported as rare but hospital admission has been relatively common. We aimed to describe the clinical and laboratory characteristics and outcomes of individuals admitted to hospital with mpox and associated complications, including tecovirimat recipients. METHODS: In this cohort study, we undertook retrospective review of electronic clinical records and pathology data for all individuals admitted between May 6, and Aug 3, 2022, to 16 hospitals from the Specialist and High Consequence Infectious Diseases Network for Monkeypox. The hospitals were located in ten cities in England and Northern Ireland. Inclusion criteria were clinical signs consistent with mpox and MPXV DNA detected from at least one clinical sample by PCR testing. Patients admitted solely for isolation purposes were excluded from the study. Key outcomes included admission indication, complications (including pain, secondary infection, and mortality) and use of antibiotic and anti-viral treatments. Routine biochemistry, haematology, microbiology, and virology data were also collected. Outcomes were assessed in all patients with available data. FINDINGS: 156 individuals were admitted to hospital with complicated mpox during the study period. 153 (98%) were male and three (2%) were female, with a median age of 35 years (IQR 30-44). Gender data were collected from electronic patient records, which encompassed full formal review of clincian notes. The prespecified options for data collection for gender were male, female, trans, non-binary, or unknown. 105 (71%) of 148 participants with available ethnicity data were of White ethnicity and 47 (30%) of 155 were living with HIV with a median CD4 count of 510 cells per mm3 (IQR 349-828). Rectal or perianal pain (including proctitis) was the most common indication for hospital admission (44 [28%] of 156). Severe pain was reported in 89 (57%) of 156, and secondary bacterial infection in 82 (58%) of 142 individuals with available data. Median admission duration was 5 days (IQR 2-9). Ten individuals required surgery and two cases of encephalitis were reported. 38 (24%) of the 156 individuals received tecovirimat with early cessation in four cases (two owing to hepatic transaminitis, one to rapid treatment response, and one to patient choice). No deaths occurred during the study period. INTERPRETATION: Although life-threatening mpox appears rare in hospitalised populations during the current outbreak, severe mpox and associated complications can occur in immunocompetent individuals. Analgesia and management of superimposed bacterial infection are priorities for patients admitted to hospital. FUNDING: None.


Subject(s)
Mpox (monkeypox) , Humans , Female , Male , Adult , Retrospective Studies , Cohort Studies , Hospitals , Pain , Benzamides , United Kingdom/epidemiology
7.
Open Forum Infect Dis ; 9(10): ofac527, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36320201

ABSTRACT

Background: COVID-19 medicines delivery units (CMDU) were established in late December 2021 to deliver early antiviral therapy to patients classified as at risk with the aim of preventing hospitalization. Methods: We performed a service evaluation at 4 CMDUs in England. We assessed demographics and triage outcomes of CMDU referral, uptake of antiviral therapy, and the rate of subsequent hospitalizations within 2 weeks of CMDU referral. Results: Over a 3-week period, 4788 patients were referred and 3989 were ultimately assessed by a CMDU. Overall, 832 of the patients referred (17%) were judged eligible for treatment and 628 (13%) were ultimately prescribed an antiviral agent. The overall rate of admission within 14 days was 1%. Patients who were admitted were significantly older than those who did not require hospitalization. Of patients prescribed molnupiravir and sotrovimab, 1.8% and 3.2%, respectively, were admitted. Conclusions: There was a high volume of referrals to CMDU service during the initial surge of the Omicron wave in the United Kingdom. A minority of patients were judged to be eligible for therapy. In a highly vaccinated population, the overall hospitalization rate was low.

8.
Sci Rep ; 12(1): 18220, 2022 10 29.
Article in English | MEDLINE | ID: mdl-36309547

ABSTRACT

There have been numerous risk tools developed to enable triaging of SARS-CoV-2 positive patients with diverse levels of complexity. Here we presented a simplified risk-tool based on minimal parameters and chest X-ray (CXR) image data that predicts the survival of adult SARS-CoV-2 positive patients at hospital admission. We analysed the NCCID database of patient blood variables and CXR images from 19 hospitals across the UK using multivariable logistic regression. The initial dataset was non-randomly split between development and internal validation dataset with 1434 and 310 SARS-CoV-2 positive patients, respectively. External validation of the final model was conducted on 741 Accident and Emergency (A&E) admissions with suspected SARS-CoV-2 infection from a separate NHS Trust. The LUCAS mortality score included five strongest predictors (Lymphocyte count, Urea, C-reactive protein, Age, Sex), which are available at any point of care with rapid turnaround of results. Our simple multivariable logistic model showed high discrimination for fatal outcome with the area under the receiving operating characteristics curve (AUC-ROC) in development cohort 0.765 (95% confidence interval (CI): 0.738-0.790), in internal validation cohort 0.744 (CI: 0.673-0.808), and in external validation cohort 0.752 (CI: 0.713-0.787). The discriminatory power of LUCAS increased slightly when including the CXR image data. LUCAS can be used to obtain valid predictions of mortality in patients within 60 days of SARS-CoV-2 RT-PCR results into low, moderate, high, or very high risk of fatality.


Subject(s)
COVID-19 , Adult , Humans , SARS-CoV-2 , C-Reactive Protein/analysis , Urea , X-Rays , Lymphocyte Count , Retrospective Studies
9.
Bioinformatics ; 38(21): 4927-4933, 2022 10 31.
Article in English | MEDLINE | ID: mdl-36094347

ABSTRACT

MOTIVATION: A common experimental output in biomedical science is a list of genes implicated in a given biological process or disease. The gene lists resulting from a group of studies answering the same, or similar, questions can be combined by ranking aggregation methods to find a consensus or a more reliable answer. Evaluating a ranking aggregation method on a specific type of data before using it is required to support the reliability since the property of a dataset can influence the performance of an algorithm. Such evaluation on gene lists is usually based on a simulated database because of the lack of a known truth for real data. However, simulated datasets tend to be too small compared to experimental data and neglect key features, including heterogeneity of quality, relevance and the inclusion of unranked lists. RESULTS: In this study, a group of existing methods and their variations that are suitable for meta-analysis of gene lists are compared using simulated and real data. Simulated data were used to explore the performance of the aggregation methods as a function of emulating the common scenarios of real genomic data, with various heterogeneity of quality, noise level and a mix of unranked and ranked data using 20 000 possible entities. In addition to the evaluation with simulated data, a comparison using real genomic data on the SARS-CoV-2 virus, cancer (non-small cell lung cancer) and bacteria (macrophage apoptosis) was performed. We summarize the results of our evaluation in a simple flowchart to select a ranking aggregation method, and in an automated implementation using the meta-analysis by information content algorithm to infer heterogeneity of data quality across input datasets. AVAILABILITY AND IMPLEMENTATION: The code for simulated data generation and running edited version of algorithms: https://github.com/baillielab/comparison_of_RA_methods. Code to perform an optimal selection of methods based on the results of this review, using the MAIC algorithm to infer the characteristics of an input dataset, can be downloaded here: https://github.com/baillielab/maic. An online service for running MAIC: https://baillielab.net/maic. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
COVID-19 , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Algorithms , Carcinoma, Non-Small-Cell Lung/genetics , COVID-19/genetics , Lung Neoplasms/genetics , Reproducibility of Results , SARS-CoV-2 , Meta-Analysis as Topic
10.
Int J Mol Sci ; 23(13)2022 Jun 30.
Article in English | MEDLINE | ID: mdl-35806273

ABSTRACT

Acute kidney injury (AKI) is a prevalent complication in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive inpatients, which is linked to an increased mortality rate compared to patients without AKI. Here we analysed the difference in kidney blood biomarkers in SARS-CoV-2 positive patients with non-fatal or fatal outcome, in order to develop a mortality prediction model for hospitalised SARS-CoV-2 positive patients. A retrospective cohort study including data from suspected SARS-CoV-2 positive patients admitted to a large National Health Service (NHS) Foundation Trust hospital in the Yorkshire and Humber regions, United Kingdom, between 1 March 2020 and 30 August 2020. Hospitalised adult patients (aged ≥ 18 years) with at least one confirmed positive RT-PCR test for SARS-CoV-2 and blood tests of kidney biomarkers within 36 h of the RT-PCR test were included. The main outcome measure was 90-day in-hospital mortality in SARS-CoV-2 infected patients. The logistic regression and random forest (RF) models incorporated six predictors including three routine kidney function tests (sodium, urea; creatinine only in RF), along with age, sex, and ethnicity. The mortality prediction performance of the logistic regression model achieved an area under receiver operating characteristic (AUROC) curve of 0.772 in the test dataset (95% CI: 0.694-0.823), while the RF model attained the AUROC of 0.820 in the same test cohort (95% CI: 0.740-0.870). The resulting validated prediction model is the first to focus on kidney biomarkers specifically on in-hospital mortality over a 90-day period.


Subject(s)
Acute Kidney Injury , COVID-19 , Acute Kidney Injury/diagnosis , Acute Kidney Injury/etiology , Adult , Biomarkers , COVID-19/diagnosis , Hospital Mortality , Humans , Kidney , Retrospective Studies , SARS-CoV-2 , State Medicine
11.
ERJ Open Res ; 8(2)2022 Apr.
Article in English | MEDLINE | ID: mdl-35382002

ABSTRACT

Background: Neutrophil extracellular traps (NETs) are web-like DNA and protein lattices which are expelled by neutrophils to trap and kill pathogens, but which cause significant damage to the host tissue. NETs have emerged as critical mediators of lung damage, inflammation and thrombosis in coronavirus disease 2019 (COVID-19) and other diseases, but there are no therapeutics to prevent or reduce NETs that are available to patients. Methods: Neutrophils were isolated from healthy volunteers (n=9) and hospitalised patients with COVID-19 at the acute stage (n=39) and again at 3-4 months post-acute sampling (n=7). NETosis was measured by SYTOX green assays. Results: Here, we show that neutrophils isolated from hospitalised patients with COVID-19 produce significantly more NETs in response to lipopolysaccharide (LPS) compared to cells from healthy control subjects. A subset of patients was captured at follow-up clinics (3-4 months post-acute sampling), and while LPS-induced NET formation is significantly lower at this time point, it remains elevated compared to healthy controls. LPS- and phorbol myristate acetate (PMA)-induced NETs were significantly inhibited by the protein kinase C (PKC) inhibitor ruboxistaurin. Ruboxistaurin-mediated inhibition of NETs in healthy neutrophils reduces NET-induced epithelial cell death. Conclusion: Our findings suggest ruboxistaurin could reduce proinflammatory and tissue-damaging consequences of neutrophils during disease, and since it has completed phase III trials for other indications without safety concerns, it is a promising and novel therapeutic strategy for COVID-19.

12.
Adv Microb Physiol ; 80: 35-83, 2022.
Article in English | MEDLINE | ID: mdl-35489793

ABSTRACT

Neisseria gonorrhoeae is an obligate human pathogen that is the cause of the sexually transmitted disease gonorrhoea. Recently, there has been a surge in gonorrhoea cases that has been exacerbated by the rapid rise in gonococcal multidrug resistance to all useful antimicrobials resulting in this organism becoming a significant public health burden. Therefore, there is a clear and present need to understand the organism's biology through its physiology and pathogenesis to help develop new intervention strategies. The gonococcus initially colonises and adheres to host mucosal surfaces utilising a type IV pilus that helps with microcolony formation. Other adhesion strategies include the porin, PorB, and the phase variable outer membrane protein Opa. The gonococcus is able to subvert complement mediated killing and opsonisation by sialylation of its lipooligosaccharide and deploys a series of anti-phagocytic mechanisms. N. gonorrhoeae is a fastidious organism that is able to grow on a limited number of primary carbon sources such as glucose and lactate. The utilization of lactate by the gonococcus has been implicated in a number of pathogenicity mechanisms. The bacterium lives mainly in microaerobic environments and can grow both aerobically and anaerobically with the aid of nitrite. The gonococcus does not produce siderophores for scavenging iron but can utilize some produced by other bacteria, and it is able to successful chelate iron from host haem, transferrin and lactoferrin. The gonococcus is an incredibly versatile human pathogen; in the following chapter, we detail the intricate mechanisms used by the bacterium to invade and survive within the host.


Subject(s)
Gonorrhea , Neisseria gonorrhoeae , Gonorrhea/microbiology , Humans , Iron/metabolism , Lactates/metabolism , Neisseria gonorrhoeae/metabolism , Virulence
14.
Front Immunol ; 12: 573266, 2021.
Article in English | MEDLINE | ID: mdl-34046027

ABSTRACT

Epigenetic modifications regulate gene expression in the host response to a diverse range of pathogens. The extent and consequences of epigenetic modification during macrophage responses to Streptococcus pneumoniae, and the role of pneumolysin, a key Streptococcus pneumoniae virulence factor, in influencing these responses, are currently unknown. To investigate this, we infected human monocyte derived macrophages (MDMs) with Streptococcus pneumoniae and addressed whether pneumolysin altered the epigenetic landscape and the associated acute macrophage transcriptional response using a combined transcriptomic and proteomic approach. Transcriptomic analysis identified 503 genes that were differentially expressed in a pneumolysin-dependent manner in these samples. Pathway analysis highlighted the involvement of transcriptional responses to core innate responses to pneumococci including modules associated with metabolic pathways activated in response to infection, oxidative stress responses and NFκB, NOD-like receptor and TNF signalling pathways. Quantitative proteomic analysis confirmed pneumolysin-regulated protein expression, early after bacterial challenge, in representative transcriptional modules associated with innate immune responses. In parallel, quantitative mass spectrometry identified global changes in the relative abundance of histone post translational modifications (PTMs) upon pneumococcal challenge. We identified an increase in the relative abundance of H3K4me1, H4K16ac and a decrease in H3K9me2 and H3K79me2 in a PLY-dependent fashion. We confirmed that pneumolysin blunted early transcriptional responses involving TNF-α and IL-6 expression. Vorinostat, a histone deacetylase inhibitor, similarly downregulated TNF-α production, reprising the pattern observed with pneumolysin. In conclusion, widespread changes in the macrophage transcriptional response are regulated by pneumolysin and are associated with global changes in histone PTMs. Modulating histone PTMs can reverse pneumolysin-associated transcriptional changes influencing innate immune responses, suggesting that epigenetic modification by pneumolysin plays a role in dampening the innate responses to pneumococci.


Subject(s)
Bacterial Proteins/metabolism , Epigenesis, Genetic , Gene Expression Profiling , Macrophages/metabolism , Streptococcus pneumoniae/metabolism , Streptolysins/metabolism , Bacterial Proteins/genetics , Cells, Cultured , Cytokines/genetics , Cytokines/metabolism , Histones/metabolism , Host-Pathogen Interactions , Humans , Macrophages/microbiology , Methylation , Protein Processing, Post-Translational , Proteome/metabolism , Proteomics/methods , Streptococcus pneumoniae/genetics , Streptococcus pneumoniae/physiology , Streptolysins/genetics
15.
Diagn Microbiol Infect Dis ; 100(1): 115305, 2021 May.
Article in English | MEDLINE | ID: mdl-33454560

ABSTRACT

This study aims to identify factors associated with duration of intravenous (IV) and follow-on oral antibiotic therapy for cellulitis in patients treated through outpatient parenteral antimicrobial therapy (OPAT). A retrospective review of episodes of cellulitis treated over a year (January 2018-January 2019) at a large teaching hospital in Sheffield, UK. Overall, 292 OPAT episodes of cellulitis were reviewed. The mean durations of IV therapy and follow-on oral antibiotics were 5.3 days (range 1-32 days) and 6.1 days (range 2-17 days), respectively. Age, peak C-reactive protein and frequency of medical assessments during OPAT were independently associated with longer duration of IV therapy. Senior clinicians were likely to prescribe shorter courses of follow-on oral antibiotics. IV to oral conversion was more likely to occur on the first day of the work week. Our findings suggest that clinical and OPAT-related factors can influence early conversion to oral antibiotic therapy.


Subject(s)
Anti-Infective Agents , Cellulitis/drug therapy , Cellulitis/epidemiology , Administration, Intravenous , Administration, Oral , Adult , Aged , Ambulatory Care , Anti-Infective Agents/administration & dosage , Anti-Infective Agents/therapeutic use , Duration of Therapy , Female , Humans , Male , Middle Aged , Retrospective Studies
16.
Front Immunol ; 11: 620339, 2020.
Article in English | MEDLINE | ID: mdl-33542723

ABSTRACT

Staphylococcus aureus is a member of the human commensal microflora that exists, apparently benignly, at multiple sites on the host. However, as an opportunist pathogen it can also cause a range of serious diseases. This requires an ability to circumvent the innate immune system to establish an infection. Professional phagocytes, primarily macrophages and neutrophils, are key innate immune cells which interact with S. aureus, acting as gatekeepers to contain and resolve infection. Recent studies have highlighted the important roles of macrophages during S. aureus infections, using a wide array of killing mechanisms. In defense, S. aureus has evolved multiple strategies to survive within, manipulate and escape from macrophages, allowing them to not only subvert but also exploit this key element of our immune system. Macrophage-S. aureus interactions are multifaceted and have direct roles in infection outcome. In depth understanding of these host-pathogen interactions may be useful for future therapeutic developments. This review examines macrophage interactions with S. aureus throughout all stages of infection, with special emphasis on mechanisms that determine infection outcome.


Subject(s)
Host-Pathogen Interactions/immunology , Macrophages/immunology , Staphylococcal Infections/immunology , Staphylococcus aureus/immunology , Animals , Anti-Bacterial Agents/pharmacology , Antimicrobial Cationic Peptides/physiology , Bacterial Vaccines , Cations/metabolism , Cell Death , Chemotaxis , Cytokines/metabolism , Extracellular Vesicles/metabolism , Humans , Hydrogen-Ion Concentration , Immune Evasion/immunology , Macrophages/classification , Macrophages/enzymology , Macrophages/microbiology , Mice , Nutrients/metabolism , Phagocytosis , Phagosomes/chemistry , Reactive Nitrogen Species/metabolism , Reactive Oxygen Species/metabolism , Receptors, Complement/physiology , Receptors, Fc/immunology , Receptors, Scavenger/physiology , Staphylococcus aureus/drug effects
17.
Rapid Commun Mass Spectrom ; 33(10): 897-906, 2019 May 30.
Article in English | MEDLINE | ID: mdl-30701600

ABSTRACT

RATIONALE: Histone post-translational modifications (PTMs) play key roles in regulating eukaryotic gene expression. Mass spectrometry (MS) has emerged as a powerful method to characterize and quantify histone PTMs as it allows unbiased identification and quantification of multiple histone PTMs including combinations of the modifications present. METHODS: In this study we compared a range of data-acquisition methods for the identification and quantification of the histone PTMs using a Q Exactive HF Orbitrap. We compared three different data-dependent analysis (DDA) methods with MS2 resolutions of 120K, 60K, 30K. We also compared a range of data-independent analysis (DIA) methods using MS2 isolation windows of 20 m/z and DIAvw to identify and quantify histone PTMs in Chinese hamster ovary (CHO) cells. RESULTS: The increased number of MS2 scans afforded by the lower resolution methods resulted in a higher number of queries, peptide sequence matches (PSMs) and a higher number of peptide proteoforms identified with a Mascot Ion score greater than 46. No difference in the proportion of peptide proteoforms with Delta scores >17 was observed. Lower coefficients of variation (CVs) were obtained in the DIA MS1 60 K MS2 30 K 20 m/z isolation windows compared with the other data-acquisition methods. CONCLUSIONS: We observed that DIA which offers advantages in flexibility and identification of isobaric peptide proteoforms performs as well as DDA in the analysis of histone PTMs. We were able to identify 71 modified histone peptides for histone H3 and H4 and quantified 64 across each of the different acquisition methods.


Subject(s)
Histones/chemistry , Mass Spectrometry/methods , Animals , CHO Cells , Cricetinae , Cricetulus , Humans , Mass Spectrometry/instrumentation , Molecular Weight , Peptides/chemistry , Protein Processing, Post-Translational
18.
Am J Respir Crit Care Med ; 198(6): 739-750, 2018 09 15.
Article in English | MEDLINE | ID: mdl-29547002

ABSTRACT

RATIONALE: Previous studies have identified defects in bacterial phagocytosis by alveolar macrophages (AMs) in patients with chronic obstructive pulmonary disease (COPD), but the mechanisms and clinical consequences remain incompletely defined. OBJECTIVES: To examine the effect of COPD on AM phagocytic responses and identify the mechanisms, clinical consequences, and potential for therapeutic manipulation of these defects. METHODS: We isolated AMs and monocyte-derived macrophages (MDMs) from a cohort of patients with COPD and control subjects within the Medical Research Council COPDMAP consortium and measured phagocytosis of bacteria in relation to opsonic conditions and clinical features. MEASUREMENTS AND MAIN RESULTS: COPD AMs and MDMs have impaired phagocytosis of Streptococcus pneumoniae. COPD AMs have a selective defect in uptake of opsonized bacteria, despite the presence of antipneumococcal antibodies in BAL, not observed in MDMs or healthy donor AMs. AM defects in phagocytosis in COPD are significantly associated with exacerbation frequency, isolation of pathogenic bacteria, and health-related quality-of-life scores. Bacterial binding and initial intracellular killing of opsonized bacteria in COPD AMs was not reduced. COPD AMs have reduced transcriptional responses to opsonized bacteria, such as cellular stress responses that include transcriptional modules involving antioxidant defenses and Nrf2 (nuclear factor erythroid 2-related factor 2)-regulated genes. Agonists of the cytoprotective transcription factor Nrf2 (sulforaphane and compound 7) reverse defects in phagocytosis of S. pneumoniae and nontypeable Haemophilus influenzae by COPD AMs. CONCLUSIONS: Patients with COPD have clinically relevant defects in opsonic phagocytosis by AMs, associated with impaired transcriptional responses to cellular stress, which are reversed by therapeutic targeting with Nrf2 agonists.


Subject(s)
NF-E2-Related Factor 2/antagonists & inhibitors , Phagocytosis/drug effects , Pulmonary Disease, Chronic Obstructive/physiopathology , Adult , Aged , Case-Control Studies , Female , Humans , Isothiocyanates/pharmacology , Macrophages/drug effects , Macrophages/physiology , Macrophages, Alveolar/drug effects , Macrophages, Alveolar/physiology , Male , Middle Aged , Phagocytosis/physiology , Streptococcus pneumoniae , Sulfoxides
19.
Pharmacol Ther ; 167: 85-99, 2016 11.
Article in English | MEDLINE | ID: mdl-27519803

ABSTRACT

Epigenetic modifications are increasingly recognized as playing an important role in the pathogenesis of infectious diseases. They represent a critical mechanism regulating transcriptional profiles in the immune system that contributes to the cell-type and stimulus specificity of the transcriptional response. Recent data highlight how epigenetic changes impact macrophage functional responses and polarization, influencing the innate immune system through macrophage tolerance and training. In this review we will explore how post-translational modifications of histone tails influence immune function to specific infectious diseases. We will describe how these may influence outcome, highlighting examples derived from responses to acute bacterial pathogens, models of sepsis, maintenance of viral latency and HIV infection. We will discuss how emerging classes of pharmacological agents, developed for use in oncology and other settings, have been applied to models of infectious diseases and their potential to modulate key aspects of the immune response to bacterial infection and HIV therapy.


Subject(s)
Bacterial Infections/drug therapy , Epigenesis, Genetic , HIV Infections/drug therapy , Animals , Anti-Bacterial Agents/pharmacology , Anti-HIV Agents/pharmacology , Bacterial Infections/genetics , Bacterial Infections/immunology , Drug Design , HIV Infections/genetics , HIV Infections/immunology , Histones/metabolism , Humans , Immunity, Innate , Macrophages/metabolism , Sepsis/drug therapy , Sepsis/genetics , Sepsis/immunology
20.
J Chromatogr A ; 1453: 43-53, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-27260198

ABSTRACT

A two dimensional-liquid chromatography (2D-LC) based approach was developed for the identification and quantification of histone post translational modifications in conjunction with mass spectrometry analysis. Using a bottom-up strategy, offline 2D-LC was developed using reverse phase chromatography. A porous graphitic carbon stationary phase in the first dimension and a C18 stationary phase in the second dimension interfaced with mass spectrometry was used to analyse global levels of histone post translational modifications in human primary monocyte-derived macrophages. The results demonstrated that 84 different histone peptide proteoforms, with modifications at 18 different sites including combinatorial marks were identified, representing an increase in the identification of histone peptides by 65% and 51% compared to two different 1D-LC approaches on the same mass spectrometer. The use of the porous graphitic stationary phase in the first dimension resulted in efficient separation of histone peptides across the gradient, with good resolution and is orthogonal to the online C18 reverse phase chromatography. Overall, more histone peptides were identified using the 2D-LC approach compared to conventional 1D-LC approaches. In addition, a bioinformatic pipeline was developed in-house to enable the high throughput efficient and accurate quantification of fractionated histone peptides. The automation of a section of the downstream analysis pipeline increased the throughput of the 2D-LC-MS/MS approach for the quantification of histone post translational modifications.


Subject(s)
Chromatography, Liquid/methods , Histones/chemistry , Histones/metabolism , Protein Processing, Post-Translational , Tandem Mass Spectrometry/methods , Cells, Cultured , Chromatography, Reverse-Phase/methods , Computational Biology , Graphite/chemistry , Histones/isolation & purification , Humans , Macrophages/metabolism , Peptides/analysis , Peptides/isolation & purification , Porosity
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