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1.
Public Health ; 233: 90-99, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38865828

ABSTRACT

Patient and public involvement and engagement (PPIE) is essential for improved research outcomes and reduced research waste. To be effective, PPIE should provide opportunities for diverse groups to contribute to all research stages. However, UK ethnic minority communities remain underrepresented in research. This article describes strategies adopted in a public health research project that were effective in building trust and increasing inclusion of ethnic minority communities. The study team of researchers and PPIE partners reflects lessons learnt during the project and describe six main strategies that built meaningful levels of trust and inclusion: 1) early start to recruitment of PPIE partners; 2) relationship-focused engagement; 3) co-production and consultation activities; 4) open communication and iterative feedback; 5) co-production of project closure activities, and; 6) diverse research team. Meaningful outcomes for the community included the involvement of people from ethnic minorities as research participants and PPIE partners, community wellbeing, co-production of public health recommendations co-presented at the UK Houses of Parliament, and consortium-wide impact evidenced by the enrolment of 51 active PPIE partners. PPIE partners reflect on their research involvement, offering advice to researchers and encouraging people from ethnic minority communities to take part in research. An important message from PPIE partners is that involvement should not be restricted to projects specific to ethnic minorities but become a routine part of general population research, recognising ethnic minorities as an integral part of UK society. In conclusion, this article demonstrates that with appropriate strategies, inclusion and diversity can be achieved in public health research. We recommend researchers, practitioners and policy makers adopt these strategies when planning their public health projects.

2.
BMC Nephrol ; 24(1): 256, 2023 08 28.
Article in English | MEDLINE | ID: mdl-37641036

ABSTRACT

BACKGROUND: The majority of cases of Dent's disease are caused by pathogenic variants in the CLCN5 gene, which encodes a voltage-gated chloride ion channel (ClC-5), resulting in proximal tubular dysfunction. We present three members of the same family and one unrelated paediatric patient with the same insertion-deletion CLCN5 variant. The identification of these patients and positive familial segregation led to the re-classification of this variant from one of unknown significance to one of likely pathogenicity. CASE PRESENTATION: A 41 year old male presented with end stage kidney failure, proteinuria and haematuria. Whole genome sequencing identified an insertion-deletion variant in CLCN5, resulting in a missense change (c.1744_1745delinsAA p.(Ala582Lys)). His brother and nephew, who both exhibited renal impairment, haematuria, proteinuria, glycosuria and nephrocalcinosis, were found to have the same variant. In addition, genetic testing of an unrelated paediatric patient who presented with proteinuria and hypercalciuria, demonstrated the same variant. CONCLUSIONS: The identification of this novel variant in four individuals with features of Dent's disease, has led to the re-classification of the variant to one of likely pathogenicity. As a result, our patients and any future patients with the same variant can be offered a likely diagnosis, without the need for kidney biopsy, and their family members can be offered genetic screening.


Subject(s)
Dent Disease , Male , Humans , Child , Adult , Dent Disease/diagnosis , Dent Disease/genetics , Hematuria , Chlorides , Family , Proteinuria
3.
Graefes Arch Clin Exp Ophthalmol ; 260(3): 817-825, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34625846

ABSTRACT

PURPOSE: To compare visual outcomes, incidence of cystoid macular edema (CME), and rate of repeat epiretinal membrane (ERM) surgery following phacovitrectomy for primary and secondary ERM. METHODS: Retrospective review of 178,856 cataract surgeries from 2003 to 2015. Eyes that underwent cataract surgery combined with ERM peel were included (n = 708). Eyes were divided into primary (n = 538) and secondary (n = 170) ERM groups. Patient demographics, visual acuity (VA), and postoperative CME were recorded. RESULTS: Patients with secondary ERM had worse preoperative VA, 0.9 ± 0.6 logMAR (20/160 Snellen equivalent) as compared to patients with primary ERM, 0.6 ± 0.3 (20/80), respectively (p < 0.0001). There was no difference between the secondary and primary ERM groups in postoperative vision (0.5 ± 0.4 logMAR vs. 0.5 ± 0.3; p = 0.9962) or proportion with VA ≥ 20/40 (46.4% vs. 43.1%; p = 0.6744) at 12-24 weeks. Postoperative CME was twice as likely in the secondary ERM group (16.5%) compared to the primary ERM group (7.8%) (p = 0.0018). There was no difference in the rate of repeat ERM surgery between the secondary ERM group (1.8%) and the primary ERM group (1.5%) (p = 0.7308). CONCLUSION: Eyes with secondary ERM had significant postoperative improvement in VA. They had worse preoperative VA and had a twofold increase in postoperative CME than primary ERM.


Subject(s)
Cataract Extraction , Cataract , Epiretinal Membrane , Cataract/complications , Epiretinal Membrane/complications , Epiretinal Membrane/diagnosis , Epiretinal Membrane/surgery , Humans , Retrospective Studies , Visual Acuity , Vitrectomy
4.
Psychol Med ; 51(8): 1271-1278, 2021 06.
Article in English | MEDLINE | ID: mdl-31996279

ABSTRACT

BACKGROUND: Evidence suggests that somatic rather than cognitive depressive symptoms are risk factors for recurrent cardiac events in at-risk patients. However, this has never been explored using a time-dependent approach in a narrow time-frame, allowing a cardiac event-free time-window. METHODS: The analysis was performed on 595 participants [70.6% male, median age 72 (27-98)] drawn from the UPBEAT-UK heart disease patient cohort with 6-monthly follow-ups over 3 years. Depressive symptomatology was measured using the Patient Health Questionnaire-9 (PHQ-9) (four somatic, five cognitive items). New cardiac events (NCEs) including cardiac-related mortality were identified by expert examination of patient records. Analyses were performed using Cox proportional hazard models with delayed entry, with time-dependent depressive dimensions and covariates measured 12-18 months (median: 14.1, IQR: 3.5) prior to the event, with a 12-month cardiac event-free gap. RESULTS: There were 95 NCEs during the follow-up [median time-to-event from baseline: 22.3 months (IQR: 13.4)]. Both the somatic (HR 1.12, 95% CI 1.05-1.20, p = 0.001) and cognitive dimensions (HR 1.11, 95% CI 1.03-1.18, p = 0.004) were time-dependent risk factors for an NCE in the multi-adjusted models. Specific symptoms (poor appetite/overeating for the somatic dimension, hopelessness and feeling like a failure for the cognitive dimension) were also significantly associated. CONCLUSION: This is the first study of the association between depressive symptom dimensions and NCEs in at-risk patients using a time-to-event standardised approach. Both dimensions considered apart were independent predictors of an NCE, along with specific items, suggesting regular assessments and tailored interventions targeting specific depressive symptoms may help to prevent NCEs in at-risk populations.


Subject(s)
Depression , Medically Unexplained Symptoms , Humans , Male , Aged , Female , Depression/psychology , Cohort Studies , Cognition , United Kingdom/epidemiology
5.
J Interprof Care ; : 1-10, 2019 Dec 18.
Article in English | MEDLINE | ID: mdl-31852375

ABSTRACT

The Deans' Interprofessional Honors Colloquium (DIHC) is an honors-level interprofessional elective course that provides a seminar-based forum for students from eleven academic programs to explore the characteristics and implications of collaborative interprofessional practice around a contemporary health topic. This project-based course combines didactic presentations, interactive group learning, and an interprofessional shadowing experience with a corresponding written reflection paper. Ten semesters of Interprofessional Shadowing Reflections (n = 401) were studied via thematic and content analyses to examine the extent to which a brief interprofessional shadowing experience influenced interprofessional identity development. Interprofessional socialization framework was employed as a lens to refine themes and to track students' trajectory in developing a dual professional identity. This exploratory case study indicated that nearly all participants' reflections included content indicative of the second stage (interprofessional role learning) of the interprofessional socialization framework, and many progressed toward the third stage (dual identity development). Major themes included emergent role learning, increased differentiation among roles and care models, and increased appreciation for other professionals. The experience provided an opportunity for correction of misconceptions and improved understanding of the role and practice of other professions. Nearly all of the participating students (1) reflected on the benefits of interprofessional collaboration and (2) indicated a desire to work interprofessionally in the future, an early indication of dual identity formation. Findings indicated that the interprofessional shadowing experience and written reflection were highly valuable elements of the DIHC and provided a critical opportunity for interprofessional identity development.

6.
Clin Exp Allergy ; 48(5): 544-554, 2018 05.
Article in English | MEDLINE | ID: mdl-29431874

ABSTRACT

BACKGROUND: Chronic rhinosinusitis (CRS) is a heterogeneous chronic inflammatory disease generally divided based on the presence or absence of nasal polyps (NPs). One of the features of NPs is excessive fibrin deposition, which is associated with down-regulation of tissue plasminogen activator (t-PA) in NPs. As t-PA is expressed in epithelial cells, and epithelium is readily accessible to topical therapies, identifying compounds that can mediate the induction of t-PA would be a potential new strategy for the treatment of NPs. OBJECTIVE: The objective of this study was to determine whether short-chain fatty acids (SCFAs) can induce t-PA in airway epithelial cells via their known receptors GPR41 and GPR43. METHODS: We performed immunohistochemistry (IHC) to determine whether receptors for SCFAs, known as G protein-coupled receptor 41/free fatty acid receptor 3 (GPR41/FFAR3) and GPR43/FFAR2, are expressed in nasal tissue. Primary normal human bronchial epithelial (NHBE) cells were stimulated with different concentrations of SCFAs to test induction of t-PA, which was analysed by expression of mRNA and protein. Mediation of responses by SCFA receptors was evaluated by specific receptor gene silencing with siRNA. RESULTS: Immunohistochemistry study revealed that airway epithelial cells expressed GPR41 and GPR43. Acetic acid, propionic acid, butyric acid and valeric acid significantly induced t-PA expression from two- to tenfolds. The strongest inducer of t-PA from NHBE cells was propionic acid; cells stimulated with propionic acid released t-PA into the supernatant in its active form. Gene silencing of GPR41 and GPR43 revealed that induction of t-PA by SCFAs was dependent upon both GPR41 and GPR43. CONCLUSIONS AND CLINICAL RELEVANCE: Short-chain fatty acids were shown to induce airway epithelial cell expression of t-PA via GPR41 and GPR43. Topical delivery of potent compounds that activate these receptors may have value by reducing fibrin deposition and shrinking nasal polyp growth.


Subject(s)
Fatty Acids, Volatile/pharmacology , Receptors, Cell Surface/metabolism , Receptors, G-Protein-Coupled/metabolism , Respiratory Mucosa/drug effects , Tissue Plasminogen Activator/biosynthesis , Adult , Cells, Cultured , Female , Humans , Male , Middle Aged , Nasal Polyps/metabolism , Respiratory Mucosa/metabolism , Tissue Plasminogen Activator/drug effects
7.
Encephale ; 44(1): 22-31, 2018 Feb.
Article in French | MEDLINE | ID: mdl-27751560

ABSTRACT

OBJECTIVES: The general practitioner (GP) is the most frequently consulted health professional by patients with common mental disorders (CMD). Yet approximately half of cases are not detected by the GP. Many factors linked to the patient, the doctor and the health care system influence detection. For example, detection rates are higher when patients are better known to their GP. On the other hand, patients visiting a different GP for reasons of dissatisfaction with previous care are more likely to be detected on the survey-day. In France, a form of gatekeeping was introduced in 2005 to encourage patients to register with a doctor (most often a GP) of their choice (known as the Preferred Doctor), responsible for care coordination and referral if necessary to secondary care. Visiting a different GP, other than for non-avoidable reasons (for e.g. GP unreachable, patient on holiday), is still possible but financially sanctioned with lower reimbursement rates. We aimed to compare GP detection rates before and after the introduction of this gatekeeping scheme. Patient service use behaviour such as doctor-shopping and GP referral to secondary care were also compared. METHODS: Two cross-sectional surveys using the same study methods were carried out 10 years apart. In 2003, 46 GPs and 1151 patients participated (approximately 25 patients per GP), with a 32.7% GP participation rate. In 2013, 38 GPs participated (of which 29 had participated in the previous study, with a 85.3% "recapture" rate) and 1133 patients (approximately 30 patients per GP). Patient participation rates were 89.8% and 67%, respectively. Patients completed self-report questionnaires in the waiting room of which the DSM-IV diagnostic criteria Patient Health Questionnaire (PHQ) and an adapted version of the Client Service Receipt Inventory (CSRI) on contacts with health care services in the previous six months. For each patient, the GP completed a questionnaire giving his rating of psychiatric illness on a five-point scale with his/her diagnosis for cases, and action undertaken. RESULTS: Of the patients, 27% and 25.4% had a CMD according to the PHQ (defined as a diagnosis of minor or major depression, panic attack, anxiety or somatoform disorder) in 2003 and 2013 respectively. Corresponding detection rates were 51% and 52.6%. Rates were highest for threshold disorders: panic disorder (69.4% and 79.9% in 2003 and 2013, respectively), major depression (75% and 63.3% in 2003 and 2013, respectively) and other anxiety disorders (69.1% and 78.8% in 2003 and 2013, respectively). In 2003, the GPs declared seeing 15.5% for the first time on the survey-day, compared to 9.6% in 2013 (P=0.006). Doctor-shopping declined between the two studies, from 18.4% to 12.1% for practical and mostly unavoidable reasons, and from 9.8% to 4.2% for dissatisfaction reasons (P<0.0001). Referral to specialist doctors increased from 9.7% in 2003 to 14.7% in 2013 (P=0.014). In 2013, on the survey-day, 94.8% of patients had registered with a Preferred Doctor and 81.2% were seeing this Preferred Doctor. In 2003, 93.5% of patients declared having a usual GP and 79.9% were visiting this GP on the survey-day. CONCLUSIONS: This is one of the first studies to report data from two repeated surveys carried out before and after a change in the health service organisation, with data collected from both the patient and the GP. We report relatively high GP detection rates for the two periods, with about 50% of CMDs, including subsyndromic conditions, detected by the GP. Rates are considerably higher for the threshold disorders. The overall detection rate did not increase as expected between the two studies. Detection is a complex topic, involving issues such as the suitability of applying categorical DSM-IV criteria diagnoses to primary care, the relevance of detecting subthreshold conditions and the ability of cross-sectional studies to correctly assess the ability of GPs to recognise cases. The introduction of gatekeeping with the choice of a Preferred Doctor has led to a decline in the frequency of doctor-shopping, whatever its reason, with patients no doubt being better known to the GP. Yet it appears most patients had already chosen a GP they were loyal to before the scheme, with a similar proportion of patients consulting their chosen GP or Preferred Doctor on both survey-days in 2003 and 2013, suggesting the scheme may to some extent only have officialised what already existed with respect to having a usual GP. The French reform still allows for doctor-shopping which can be considered as a positive aspect of the scheme: patients either dissatisfied with previous care or needing to change GP are thus able to "test" and choose the doctor that best suits their needs.


Subject(s)
Gatekeeping , General Practitioners , Mental Disorders/diagnosis , Patient Health Questionnaire , Adult , Aged , Cross-Sectional Studies , Diagnostic and Statistical Manual of Mental Disorders , Female , France/epidemiology , Health Care Surveys , Health Status , Humans , Male , Mental Disorders/epidemiology , Mental Disorders/psychology , Mental Health , Middle Aged , Patient Satisfaction , Self Report , Socioeconomic Factors
8.
Clin Exp Allergy ; 47(4): 457-466, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28000955

ABSTRACT

BACKGROUND: B cells play many roles in health and disease. However, little is known about the mechanisms that drive B cell responses in the airways, especially in humans. Chronic rhinosinusitis (CRS) is an inflammatory disease of the upper airways that affects 10% of Europeans and Americans. A subset of CRS patients develop nasal polyps (NPs), which are characterized by type 2 inflammation, eosinophils and group 2 innate lymphoid cells (ILC2s). We have reported that NP contain elevated levels of B cells and antibodies, making NP an ideal system for studying B cells in the airways. OBJECTIVE: We sought to determine the mechanisms that drive B cell activation and antibody production during chronic airway inflammation. METHODS: We analysed B cells from NP or tonsil, or after ILC2 coculture, by flow cytometry. Antibody production from tissue was measured using Luminex assays and the frequency of antibody-secreting cells by ELISpot. Formation of B cell clusters was assessed using immunohistochemistry. Expression of genes associated with B cell activation and class switch recombination was measured by qRT-PCR. RESULTS: NP contained significantly elevated frequencies of plasmablasts, especially those that expressed the extrafollicular marker Epstein-Barr virus-induced protein 2 (EBI2), but significantly fewer germinal centre (GC) B cells compared with tonsil. Antibody production and the frequency of antibody-secreting cells were significantly elevated in NP, and there was evidence for local class switch recombination in NP. Finally, ILC2s directly induced EBI2 expression on B cells in vitro. CONCLUSIONS AND CLINICAL RELEVANCE: Our data suggest there is a unique B cell activation environment within NP that is distinct from classic GC-mediated mechanisms. We show for the first time that ILC2s directly induce EBI2 expression on B cells, indicating that ILC2s may play an important role in B cell responses. B cell-targeted therapies may provide new treatment options for CRSwNP.


Subject(s)
Antibody Formation/immunology , B-Lymphocytes/immunology , Inflammation/immunology , Lymphocyte Activation/immunology , Respiratory Tract Diseases/immunology , B-Lymphocyte Subsets/immunology , B-Lymphocyte Subsets/metabolism , B-Lymphocytes/metabolism , Biomarkers , Gene Expression , Humans , Immunophenotyping , Inflammation/metabolism , Inflammation/pathology , Lymphocyte Count , Nasal Polyps/immunology , Nasal Polyps/metabolism , Nasal Polyps/pathology , Plasma Cells/immunology , Plasma Cells/metabolism , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism , Respiratory Tract Diseases/metabolism , Respiratory Tract Diseases/pathology
9.
Vet Res ; 48(1): 3, 2017 01 25.
Article in English | MEDLINE | ID: mdl-28122589

ABSTRACT

The pathogenicity of Escherichia coli O78 strain K46, originally isolated from an outbreak of septicemia in neonatal lambs, was investigated in zebrafish embryo and murine models of infection. Its biofilm potential, cellulose production, and the expression of type 1 pili and curli fimbriae were measured by in vitro assays. The strain was highly pathogenic in the zebrafish embryo model of infection, where it killed all embryos within 24 h post inoculation (hpi) at doses as low as 1000 colony forming units. Zebrafish embryos inoculated with similar doses of commensal E. coli strains showed no signs of disease, and cleared the bacteria within 24 h. E. coli K46 colonized the murine gut at the same level as the uropathogenic E. coli (UPEC) reference strain CFT073 in CBA/J mice after oral inoculation, but infected the murine bladder significantly less than CFT073 after transurethral inoculation. Type 1 pili were clearly expressed by E. coli K46, while curli fimbriae and cellulose production were weakly expressed. The ability to produce biofilm varied in different growth media, but overall E. coli K46 was a poorer biofilm producer compared to the reference strain E. coli UTI89. In conclusion, the zebrafish lethality model provides further evidence that E. coli K46 is highly pathogenic and might be useful in future studies to identify bacterial virulence factors.


Subject(s)
Escherichia coli Infections/veterinary , Escherichia coli/pathogenicity , Sepsis/veterinary , Sheep Diseases/microbiology , Zebrafish/microbiology , Animals , Animals, Newborn/microbiology , Biofilms/growth & development , Disease Models, Animal , Escherichia coli/isolation & purification , Escherichia coli Infections/microbiology , Female , Gastrointestinal Tract/microbiology , Mice , Mice, Inbred CBA/microbiology , Sepsis/microbiology , Sheep/microbiology , Urinary Bladder/microbiology
10.
Osteoporos Int ; 27(11): 3187-3195, 2016 11.
Article in English | MEDLINE | ID: mdl-27311722

ABSTRACT

In this population-based elderly cohort, participants using selective serotonin reuptake inhibitor (SSRI) antidepressants have an increased risk of falls and fractures notably when the treatment was continued over 4 years. Among the various SSRI types, citalopram only was at significant risk for falls and fluoxetine for fractures. INTRODUCTION: Increased risk of falls and fractures has been reported in elderly users of SSRIs. However, biases were insufficiently addressed notably temporality between exposure and outcome and confounding by residual depression. Our objective was to examine the associations between SSRIs and fall or fracture incidence focusing on their chronic use and different types of SSRIs. METHODS: The population-based cohort included participants aged 65 years and above, who had not fallen before inclusion (n = 6599) or were free of recent fracture (n = 6823) and were followed up twice over 4 years. New fall and fracture events were self-reported and defined as at least two falls and one fracture, respectively, during the previous 2 years. SSRI users were compared with those taking no antidepressants. Hazard ratios (HRs) were estimated using Cox models with delayed entry and adjusted for many confounders including residual depressive symptoms. RESULTS: Incidence of falls was 19.3 % over 4 years and that of fractures 9.5 %. After multi-adjustment, SSRI intake was significantly associated with a higher risk of falls (HR, 95 % CI = 1.58, 1.23-2.03) and fractures (HR, 95 % CI = 1.61, 1.16-2.24). The risks were significantly increased by 80 % in those continuing the treatment over 4 years. Citalopram intake only was at significant risk for falls and fluoxetine for fractures. CONCLUSIONS: In this large community-dwelling elderly sample, SSRI users were at higher risk of falls and fractures. This association was not due to reverse causality or residual depressive symptoms. Different SSRI drugs may have specific adverse effects on falls and fractures.


Subject(s)
Accidental Falls , Antidepressive Agents/administration & dosage , Fractures, Bone/epidemiology , Selective Serotonin Reuptake Inhibitors/administration & dosage , Aged , Cohort Studies , Female , Humans , Longitudinal Studies , Male , Proportional Hazards Models , Risk Factors
11.
Eur J Neurol ; 23(9): 1463-70, 2016 09.
Article in English | MEDLINE | ID: mdl-27399611

ABSTRACT

BACKGROUND AND PURPOSE: There is evidence that migraine is a risk factor for stroke but little is known about this association in elderly people. Furthermore, non-migrainous headache (NMH) has received little attention despite being the most frequently reported type of headache. Late-life migraine and NMH were examined as candidate risk factors for stroke in a community-dwelling elderly sample over a 12-year follow-up. METHODS: One thousand nine hundred and nineteen non-institutionalized subjects aged 65+, without dementia (Diagnostic and Statistical Manual of Mental Disorders, 4th edition, DSM-IV criteria) and with no stroke history at baseline, were drawn from the Three-City Montpellier cohort (recruitment 1999-2001) for longitudinal analysis. Ischaemic and haemorrhagic stroke was reported at baseline and at each of the five follow-ups, with cases validated by a panel of experts, according to ICD-10 criteria (International Classification of Diseases, 10th revision). Migraine and NMH were determined at baseline during a neurological interview and examination using 1988 International Headache Society criteria. RESULTS: A total of 110 (5.4%) cases of migraine and 179 (8.9%) cases of NMH were identified at baseline. During the median 8.8-year follow-up, incident stroke was observed in 1.9% of baseline migrainers, 6.2% of NMH and 3.6% of those with no lifetime history of headache. Cox proportional hazard models indicated that migraine was not a risk factor for stroke; however, NMH sufferers were twice as likely to have a stroke (hazard ratio 2.00, 95% confidence interval 1.00-3.93, P = 0.049). CONCLUSIONS: This study is one of the first to suggest that late-life NMH rather than migraine could be an independent risk factor for stroke and a warning sign. The incidence of stroke in elderly migrainers, seldom reported, is particularly low.


Subject(s)
Headache Disorders/complications , Headache Disorders/epidemiology , Migraine Disorders/complications , Migraine Disorders/epidemiology , Stroke/etiology , Adult , Aged , Aged, 80 and over , Cohort Studies , Diagnostic and Statistical Manual of Mental Disorders , Female , Follow-Up Studies , France/epidemiology , Humans , Incidence , Male , Middle Aged , Risk Factors , Socioeconomic Factors
12.
PLoS Genet ; 9(8): e1003716, 2013.
Article in English | MEDLINE | ID: mdl-23990803

ABSTRACT

Strains of Extraintestinal Pathogenic Escherichia c oli (ExPEC) exhibit an array of virulence strategies and are a major cause of urinary tract infections, sepsis and meningitis. Efforts to understand ExPEC pathogenesis are challenged by the high degree of genetic and phenotypic variation that exists among isolates. Determining which virulence traits are widespread and which are strain-specific will greatly benefit the design of more effective therapies. Towards this goal, we utilized a quantitative genetic footprinting technique known as transposon insertion sequencing (Tn-seq) in conjunction with comparative pathogenomics to functionally dissect the genetic repertoire of a reference ExPEC isolate. Using Tn-seq and high-throughput zebrafish infection models, we tracked changes in the abundance of ExPEC variants within saturated transposon mutant libraries following selection within distinct host niches. Nine hundred and seventy bacterial genes (18% of the genome) were found to promote pathogen fitness in either a niche-dependent or independent manner. To identify genes with the highest therapeutic and diagnostic potential, a novel Trait Enrichment Analysis (TEA) algorithm was developed to ascertain the phylogenetic distribution of candidate genes. TEA revealed that a significant portion of the 970 genes identified by Tn-seq have homologues more often contained within the genomes of ExPEC and other known pathogens, which, as suggested by the first axiom of molecular Koch's postulates, is considered to be a key feature of true virulence determinants. Three of these Tn-seq-derived pathogen-associated genes--a transcriptional repressor, a putative metalloendopeptidase toxin and a hypothetical DNA binding protein--were deleted and shown to independently affect ExPEC fitness in zebrafish and mouse models of infection. Together, the approaches and observations reported herein provide a resource for future pathogenomics-based research and highlight the diversity of factors required by a single ExPEC isolate to survive within varying host environments.


Subject(s)
Escherichia coli/pathogenicity , Meningitis/genetics , Sepsis/genetics , Urinary Tract Infections/genetics , Animals , DNA Transposable Elements/genetics , Disease Models, Animal , Escherichia coli/genetics , Genetic Fitness , Genome, Bacterial , Meningitis/microbiology , Mice , Phylogeny , Sepsis/microbiology , Urinary Tract Infections/microbiology , Zebrafish/genetics
13.
Dev Biol ; 393(1): 171-82, 2014 Sep 01.
Article in English | MEDLINE | ID: mdl-24929237

ABSTRACT

Motility of sperm is crucial for their directed migration to the egg. The acquisition and modulation of motility are regulated to ensure that sperm move when and where needed, thereby promoting reproductive success. One specific example of this phenomenon occurs during differentiation of the ameboid sperm of Caenorhabditis elegans as they activate from a round spermatid to a mature, crawling spermatozoon. Sperm activation is regulated by redundant pathways to occur at a specific time and place for each sex. Here, we report the identification of the solute carrier 6 (SLC6) transporter protein SNF-10 as a key regulator of C. elegans sperm activation in response to male protease activation signals. We find that SNF-10 is present in sperm and is required for activation by the male but not by the hermaphrodite. Loss of both snf-10 and a hermaphrodite activation factor render sperm completely insensitive to activation. Using in vitro assays, we find that snf-10 mutant sperm show a specific deficit in response to protease treatment but not to other activators. Prior to activation, SNF-10 is present in the plasma membrane, where it represents a strong candidate to receive signals that lead to subcellular morphogenesis. After activation, it shows polarized localization to the cell body region that is dependent on membrane fusions mediated by the dysferlin FER-1. Our discovery of snf-10 offers insight into the mechanisms differentially employed by the two sexes to accomplish the common goal of producing functional sperm, as well as how the physiology of nematode sperm may be regulated to control motility as it is in mammals.


Subject(s)
Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans/physiology , GABA Plasma Membrane Transport Proteins/physiology , Sperm Motility/physiology , Spermatozoa/cytology , Animals , Animals, Genetically Modified , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/biosynthesis , Caenorhabditis elegans Proteins/metabolism , GABA Plasma Membrane Transport Proteins/biosynthesis , GABA Plasma Membrane Transport Proteins/genetics , Hermaphroditic Organisms , Male , Membrane Proteins/metabolism , Morphogenesis , Mutation , Sperm Motility/genetics , Spermatogenesis
14.
PLoS Pathog ; 9(2): e1003175, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23459509

ABSTRACT

In bacteria, laterally acquired genes are often concentrated within chromosomal regions known as genomic islands. Using a recently developed zebrafish infection model, we set out to identify unique factors encoded within genomic islands that contribute to the fitness and virulence of a reference urosepsis isolate-extraintestinal pathogenic Escherichia coli strain CFT073. By screening a series of deletion mutants, we discovered a previously uncharacterized gene, neaT, that is conditionally required by the pathogen during systemic infections. In vitro assays indicate that neaT can limit bacterial interactions with host phagocytes and alter the aggregative properties of CFT073. The neaT gene is localized within an integrated P2-like bacteriophage in CFT073, but was rarely found within other proteobacterial genomes. Sequence-based analyses revealed that neaT homologues are present, but discordantly conserved, within a phyletically diverse set of bacterial species. In CFT073, neaT appears to be unameliorated, having an exceptionally A+T-rich composition along with a notably altered codon bias. These data suggest that neaT was recently brought into the proteobacterial pan-genome from an extra-phyletic source. Interestingly, even in G+C-poor genomes, as found within the Firmicutes lineage, neaT-like genes are often unameliorated. Sequence-level features of neaT homologues challenge the common supposition that the A+T-rich nature of many recently acquired genes reflects the nucleotide composition of their genomes of origin. In total, these findings highlight the complexity of the evolutionary forces that can affect the acquisition, utilization, and assimilation of rare genes that promote the niche-dependent fitness and virulence of a bacterial pathogen.


Subject(s)
Escherichia coli Infections/microbiology , Escherichia coli Proteins/physiology , Genetic Fitness , Urinary Tract Infections/microbiology , Uropathogenic Escherichia coli/pathogenicity , Virulence/genetics , Zebrafish/microbiology , Animals , Biological Evolution , Disease Models, Animal , Embryo, Nonmammalian/metabolism , Embryo, Nonmammalian/microbiology , Escherichia coli Infections/genetics , Female , Gene Expression Regulation, Bacterial , Genome, Bacterial , Genomic Islands , Host-Pathogen Interactions , Mice , Mice, Inbred CBA/microbiology , Phylogeny , Urinary Tract Infections/genetics , Zebrafish/genetics
15.
Clin Exp Allergy ; 45(2): 384-93, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25469646

ABSTRACT

BACKGROUND: Although chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by Th2 inflammation, the mechanism underlying the onset and amplification of this inflammation has not been fully elucidated. Dendritic cells (DCs) are major antigen-presenting cells, central inducers of adaptive immunity and critical regulators of many inflammatory diseases. However, the presence of DCs in CRS, especially in nasal polyps (NPs), has not been extensively studied. OBJECTIVE: The objective of this study was to characterize DC subsets in CRS. METHODS: We used real-time PCR to assess the expression of mRNA for markers of myeloid DCs (mDCs; CD1c), plasmacytoid DCs (pDCs; CD303) and Langerhans cells (LCs; CD1a, CD207) in uncinate tissue (UT) from controls and patients with CRS as well as in NP. We assayed the presence of DCs by immunohistochemistry and flow cytometry. RESULTS: Compared to UT from control subjects (n = 15) and patients with CRS without NP (CRSsNP) (n = 16) and CRSwNP (n = 17), mRNAs for CD1a and CD1c were significantly elevated in NPs (n = 29). In contrast, CD207 mRNA was not elevated in NPs. Immunohistochemistry showed that CD1c(+) cells but not CD303(+) cells were significantly elevated in NPs compared to control subjects or patients with CRSsNP. Flow cytometric analysis showed that CD1a(+) cells in NPs might be a subset of mDC1s and that CD45(+) CD19(-) CD1c(+) CD11c(+) CD141(-) CD303(-) HLA-DR(+) mDC1s and CD45(+) CD19(-) CD11c(+) CD1c(-) CD141(high) HLA-DR(+) mDC2s were significantly elevated in NPs compared to UT from controls and CRSsNP, but CD45(+) CD11c(-) CD303(+) HLA-DR(+) pDCs were only elevated in NPs compared to control UT. CONCLUSION AND CLINICAL RELEVANCE: Myeloid DCs are elevated in CRSwNP, especially in NPs. Myeloid DCs thus may indirectly contribute to the inflammation observed in CRSwNP.


Subject(s)
Dendritic Cells/immunology , Myeloid Cells/immunology , Nasal Polyps/immunology , Rhinitis/immunology , Sinusitis/immunology , Adult , Aged , Antigens, Surface/genetics , Antigens, Surface/metabolism , Biomarkers , Chronic Disease , Dendritic Cells/metabolism , Female , Humans , Immunohistochemistry , Immunophenotyping , Male , Middle Aged , Myeloid Cells/metabolism , Nasal Polyps/complications , Nasal Polyps/metabolism , Real-Time Polymerase Chain Reaction , Rhinitis/complications , Rhinitis/metabolism , Sinusitis/complications , Sinusitis/metabolism , Th2 Cells/immunology , Th2 Cells/metabolism , Young Adult
16.
MMWR Morb Mortal Wkly Rep ; 64(12): 318-20, 2015 Apr 03.
Article in English | MEDLINE | ID: mdl-25837241

ABSTRACT

In December 2014, PulseNet, the national molecular subtyping network for foodborne disease, detected a multistate cluster of Shigella sonnei infections with an uncommon pulsed-field gel electrophoresis (PFGE) pattern. CDC's National Antimicrobial Resistance Monitoring System (NARMS) laboratory determined that isolates from this cluster were resistant to ciprofloxacin, the antimicrobial medication recommended to treat adults with shigellosis. To understand the scope of the outbreak and to try to identify its source, CDC and state and local health departments conducted epidemiologic and laboratory investigations. During May 2014-February 2015, PulseNet identified 157 cases in 32 states and Puerto Rico; approximately half were associated with international travel. Nine of the cases identified by PulseNet, and another 86 cases without PFGE data, were part of a related outbreak of ciprofloxacin-resistant shigellosis in San Francisco, California. Of 126 total isolates with antimicrobial susceptibility information, 109 (87%) were nonsusceptible to ciprofloxacin (108 were resistant, and one had intermediate susceptibility). Travelers need to be aware of the risks of acquiring multidrug-resistant pathogens, carefully wash their hands, and adhere to food and water precautions during international travel. Clinicians should request stool cultures and antimicrobial susceptibilities when they suspect shigellosis, and counsel shigellosis patients to follow meticulous hygiene regimens while ill.


Subject(s)
Anti-Bacterial Agents/pharmacology , Ciprofloxacin/pharmacology , Disease Outbreaks , Drug Resistance, Bacterial , Dysentery, Bacillary/epidemiology , Shigella sonnei/drug effects , Travel/statistics & numerical data , Adult , Cluster Analysis , Dysentery, Bacillary/prevention & control , Dysentery, Bacillary/transmission , Electrophoresis, Gel, Pulsed-Field , Female , Humans , Internationality , Male , Middle Aged , Shigella sonnei/isolation & purification , United States/epidemiology , Young Adult
17.
MMWR Morb Mortal Wkly Rep ; 64(21): 597-8, 2015 Jun 05.
Article in English | MEDLINE | ID: mdl-26042652

ABSTRACT

Increasing rates of shigellosis among adult males, particularly men who have sex with men (MSM), have been documented in the United States, Canada, and Europe, and MSM appear to be at greater risk for infection with shigellae that are not susceptible to ciprofloxacin or azithromycin. Azithromycin is the first-line empiric antimicrobial treatment for shigellosis among children and is a second-line treatment among adults. Isolates collected in 2014 in two U.S. cities from outbreaks of shigellosis displayed highly similar pulsed-field gel electrophoresis (PFGE) patterns and decreased susceptibility to azithromycin (DSA). This report summarizes and compares the findings from investigations of the two outbreaks, which occurred among MSM in metropolitan Minneapolis-St. Paul, Minnesota, and Chicago, Illinois.


Subject(s)
Anti-Bacterial Agents/pharmacology , Azithromycin/pharmacology , Disease Outbreaks , Drug Resistance, Bacterial , Dysentery, Bacillary/epidemiology , Homosexuality, Male , Shigella sonnei/drug effects , Adult , Anti-Bacterial Agents/therapeutic use , Azithromycin/therapeutic use , Chicago/epidemiology , Dysentery, Bacillary/diagnosis , Dysentery, Bacillary/drug therapy , Electrophoresis, Gel, Pulsed-Field , Homosexuality, Male/statistics & numerical data , Humans , Male , Middle Aged , Minnesota/epidemiology , Shigella sonnei/isolation & purification , Young Adult
18.
J Public Health Manag Pract ; 21 Suppl 3: S110-5, 2015.
Article in English | MEDLINE | ID: mdl-25828213

ABSTRACT

BACKGROUND: Children in Buffalo, New York, have limited opportunities for safe, enjoyable physical activity. The Healthy Kids, Healthy Communities-Buffalo partnership established in 2009 created environmental and policy supports to facilitate physical activity among youth. METHODS: This article uses a mixed-methods approach to document environment and policy changes in support of active commuting to school. Built environment data were collected using a pre-post research design with the Street Design Environmental Audit Tool. Supplementary sources of information include Geographic Information Systems, US Census data, and property parcel data. RESULTS: This exploratory study found modest improvements in the built environment during the period of assessment. Specifically, sidewalk conditions were improved. In addition, assessment of citywide policy indicates that systemic supports for active living have been put into place through the new (proposed) land use plan and the proposed zoning ordinance. CONCLUSIONS: Exploratory evaluation results suggest that Healthy Kids, Healthy Communities-Buffalo partnership was able to make some environmental and policy changes to promote active transportation. A long-term assessment is required to develop a fuller understanding of how environmental and policy changes impact active transportation.


Subject(s)
Health Behavior , Health Policy , Health Promotion/methods , Transportation/standards , Environment Design/standards , Exercise/psychology , Geographic Information Systems , Humans , New York , Pediatric Obesity/prevention & control , Pediatric Obesity/psychology , Program Evaluation/methods
19.
PLoS Pathog ; 8(10): e1002954, 2012.
Article in English | MEDLINE | ID: mdl-23055930

ABSTRACT

Toxin-antitoxin (TA) systems are prevalent in many bacterial genomes and have been implicated in biofilm and persister cell formation, but the contribution of individual chromosomally encoded TA systems during bacterial pathogenesis is not well understood. Of the known TA systems encoded by Escherichia coli, only a subset is associated with strains of extraintestinal pathogenic E. coli (ExPEC). These pathogens colonize diverse niches and are a major cause of sepsis, meningitis, and urinary tract infections. Using a murine infection model, we show that two TA systems (YefM-YoeB and YbaJ-Hha) independently promote colonization of the bladder by the reference uropathogenic ExPEC isolate CFT073, while a third TA system comprised of the toxin PasT and the antitoxin PasI is critical to ExPEC survival within the kidneys. The PasTI TA system also enhances ExPEC persister cell formation in the presence of antibiotics and markedly increases pathogen resistance to nutrient limitation as well as oxidative and nitrosative stresses. On its own, low-level expression of PasT protects ExPEC from these stresses, whereas overexpression of PasT is toxic and causes bacterial stasis. PasT-induced stasis can be rescued by overexpression of PasI, indicating that PasTI is a bona fide TA system. By mutagenesis, we find that the stress resistance and toxic effects of PasT can be uncoupled and mapped to distinct domains. Toxicity was specifically linked to sequences within the N-terminus of PasT, a region that also promotes the development of persister cells. These results indicate discrete, multipurpose functions for a TA-associated toxin and demonstrate that individual TA systems can provide bacteria with pronounced fitness advantages dependent on toxin expression levels and the specific environmental niche occupied.


Subject(s)
Bacterial Toxins/genetics , Bacterial Toxins/metabolism , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Urinary Tract Infections/microbiology , Uropathogenic Escherichia coli/metabolism , Animals , Antitoxins/genetics , Antitoxins/metabolism , DNA-Binding Proteins/metabolism , Gene Expression Regulation, Bacterial , Mice , Mice, Inbred C3H , Urinary Bladder/microbiology
20.
Infect Immun ; 81(1): 249-58, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23115037

ABSTRACT

In many bacteria, the second messenger cyclic AMP (cAMP) interacts with the transcription factor cAMP receptor protein (CRP), forming active cAMP-CRP complexes that can control a multitude of cellular activities, including expanded carbon source utilization, stress response pathways, and virulence. Here, we assessed the role of cAMP-CRP as a regulator of stress resistance and virulence in uropathogenic Escherichia coli (UPEC), the principal cause of urinary tract infections worldwide. Deletion of genes encoding either CRP or CyaA, the enzyme responsible for cAMP synthesis, attenuates the ability of UPEC to colonize the bladder in a mouse infection model, dependent on intact innate host defenses. UPEC mutants lacking cAMP-CRP grow normally in the presence of glucose but are unable to utilize alternate carbon sources like amino acids, the primary nutrients available to UPEC within the urinary tract. Relative to the wild-type UPEC isolate, the cyaA and crp deletion mutants are sensitive to nitrosative stress and the superoxide generator methyl viologen but remarkably resistant to hydrogen peroxide (H(2)O(2)) and acid stress. In the mutant strains, H(2)O(2) resistance correlates with elevated catalase activity attributable in part to enhanced translation of the alternate sigma factor RpoS. Acid resistance was promoted by both RpoS-independent and RpoS-dependent mechanisms, including expression of the RpoS-regulated DNA-binding ferritin-like protein Dps. We conclude that balanced input from many cAMP-CRP-responsive elements, including RpoS, is critical to the ability of UPEC to handle the nutrient limitations and severe environmental stresses present within the mammalian urinary tract.


Subject(s)
Adenylyl Cyclases/metabolism , Cyclic AMP Receptor Protein/metabolism , Cyclic AMP/metabolism , Escherichia coli Infections/metabolism , Uropathogenic Escherichia coli/metabolism , Adenylyl Cyclases/genetics , Amino Acids/metabolism , Animals , Bacterial Outer Membrane Proteins/genetics , Bacterial Outer Membrane Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Cyclic AMP/genetics , Cyclic AMP Receptor Protein/genetics , Escherichia coli Infections/genetics , Escherichia coli Infections/microbiology , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Female , Glucose/metabolism , Hydrogen Peroxide/metabolism , Lactose/metabolism , Mice , Mice, Inbred C3H , Mice, Inbred CBA , Paraquat/metabolism , Sigma Factor/genetics , Sigma Factor/metabolism , Superoxides/metabolism , Urinary Bladder/metabolism , Urinary Bladder/microbiology , Urinary Tract Infections/genetics , Urinary Tract Infections/metabolism , Urinary Tract Infections/microbiology , Uropathogenic Escherichia coli/enzymology , Uropathogenic Escherichia coli/genetics , Virulence
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