mparing Urolift and tandard ransurethral resection of prostate head of adiotherapy in men with urinary symptoms secondary to prostate enlargement in Southwest London and North Cumbria (CO-STAR): a study protocol for a randomised feasibility study

INTRODUCTION

Patients undergoing prostate radiotherapy with an enlarged prostate can have short-term and long-term urinary complications. Currently, transurethral resection of the prostate (TURP) is the mainstay surgical intervention for men with urinary symptoms due to an enlarged prostate prior to radiotherapy. UroLift (NeoTract, Pleasanton, CA, USA) is a recent minimally invasive alternative, widely used in benign disease but is untested in men with prostate cancer.

METHODS AND ANALYSIS

A multicentre, two-arm study designed in collaboration with a Patient Reference Group to assess the feasibility of randomising men with prostate cancer and coexisting urinary symptoms due to prostate enlargement to TURP or UroLift ahead of radiotherapy. 45 patients will be enrolled and randomised (1:1) using a computer-generated programme to TURP or UroLift. Recruitment and retention will be assessed over a 12 month period. Information on clinical outcomes, adverse events and costs will be collected. Clinical outcomes and patient reported outcome measures will be measured at baseline, 6 weeks postintervention and 3 months following radiotherapy. A further 12 in-depth interviews will be conducted with a subset of patients to assess acceptability using the Theoretical Framework of Acceptability. Descriptive analysis on all outcomes will be performed using Stata (StataCorp V.2021).

ETHICS AND DISSEMINATION

The trial has been approved by the Research Ethics Committee (REC) NHS Health Research Authority (HRA) and Health and Care Research Wales (HCRW). The results will be published in peer-reviewed journals, presented at national meetings and disseminated to patients via social media, charity and hospital websites.

TRIAL REGISTRATION NUMBER

NCT05840549.

Mobile Health Solutions for Prostate Cancer Diagnostics-A Systematic Review

Prostate cancer, the most common cause of cancer in men in the UK and one of the most common around the world to date, has no consensus on screening. Multiple large-scale trials from around the world have produced conflicting outcomes in cancer-specific and overall mortality. A main part of the issue is the PSA test, which has a high degree of variability, making it challenging to set PSA thresholds, as well as limited specificity. Prostate cancer has a predisposition in men from black backgrounds, and outcomes are worse in men of lower socioeconomic groups. Mobile targeted case finding, focusing on high-risk groups, may be a solution to help those that most need it. The aim of this systematic review was to review the evidence for mobile testing for prostate cancer. A review of all mobile screening studies for prostate cancer was performed in accordance with the Cochrane guidelines and the PRISMA statement. Of the 629 unique studies screened, 6 were found to be eligible for the review. The studies dated from 1973 to 2017 and came from four different continents, with around 30,275 men being screened for prostate cancer. Detection rates varied from 0.6% in the earliest study to 8.2% in the latest study. The challenge of early diagnosis of potentially lethal prostate cancer remains an issue for developed and low- and middle-income countries alike. Although further studies are needed, mobile screening of a targeted population with streamlined investigation and referral pathways combined with raising awareness in those communities may help make the case for screening for prostate cancer.

The profile study: Prostate cancer screening in men of Black African and African Caribbean ancestry—Early results

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Background: Heritable risk factors account for a significant proportion of prostate cancer (PrCa) risk, of which only a minority are high risk Mendelian traits. Men of Black African and African Caribbean ancestry are at higher risk of developing PrCa in their lifetime (1 in 4) compared with the general population in the United Kingdom (1 in 8). PROFILE is a multi-cohort study of targeted screening for groups of men at higher risk of developing PrCa: 1) men of European ancestry with family history of PrCa, 2) men of black African and African Caribbean ancestry regardless of family history and 3) men with known rarer higher risk gene mutations for PrCa. This abstract concentrates on group 2. The aim is to investigate the role of targeted PrCa screening in men at higher genetic risk and its association with specific genetic profiles and biomarkers. Methods: Healthy men aged 40-69 are invited to participate. Inclusion Criteria: Both parents and all four grandparents must be of either black African or African Caribbean ancestry. Arm 1: PSA only – once PSA is below an age-related threshold (aged 40-49 and PSA ≥0ng/ml, aged 50-69 PSA >/= 2ng/ml) they continue on the study with annual PSA, only triggering a prostate MRI and Biopsy if the PSA is above the threshold. Arm 2: Regardless of PSA men opt for prostate mpMRI and biopsy. Polygenic risk score (PRS) calculated based on 230 SNPs including latest AA specific variants. Results: Arm 1: 121 enrolled PSA only (this has triggered 8 biopsies with 3 cancers). Arm 2: 58 enrolled MRI and biopsy, 58 MRIs and 36 biopsies carried out, PrCa detected in 15 men (42%). 22% are Gleason score ≥7. Association between PRS and MRI/Biopsy results will be presented. Conclusions: We will continue to perform MRI and biopsies on men, we will also carry out polygenic risk scores on these men to verify whether a genetic PRS can help guide enhanced screening for certain men in the population. Although data are early, a significant proportion of biopsies are positive for PrCa that needs radical treatment. Clinical trial information: NCT02543905 .

Best Current Practice and Research Priorities in Active Surveillance for Prostate Cancer-A Report of a Movember International Consensus Meeting

BACKGROUND

Active surveillance (AS) is recommended for low-risk and some intermediate-risk prostate cancer. Uptake and practice of AS vary significantly across different settings, as does the experience of surveillance-from which tests are offered, and to the levels of psychological support.

OBJECTIVE

To explore the current best practice and determine the most important research priorities in AS for prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

A formal consensus process was followed, with an international expert panel of purposively sampled participants across a range of health care professionals and researchers, and those with lived experience of prostate cancer. Statements regarding the practice of AS and potential research priorities spanning the patient journey from surveillance to initiating treatment were developed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Panel members scored each statement on a Likert scale. The group median score and measure of consensus were presented to participants prior to discussion and rescoring at panel meetings. Current best practice and future research priorities were identified, agreed upon, and finally ranked by panel members.

RESULTS AND LIMITATIONS

There was consensus agreement that best practice includes the use of high-quality magnetic resonance imaging (MRI), which allows digital rectal examination (DRE) to be omitted, that repeat standard biopsy can be omitted when MRI and prostate-specific antigen (PSA) kinetics are stable, and that changes in PSA or DRE should prompt MRI ± biopsy rather than immediate active treatment. The highest ranked research priority was a dynamic, risk-adjusted AS approach, reducing testing for those at the least risk of progression. Improving the tests used in surveillance, ensuring equity of access and experience across different patients and settings, and improving information and communication between and within clinicians and patients were also high priorities. Limitations include the use of a limited number of panel members for practical reasons.

CONCLUSIONS

The current best practice in AS includes the use of high-quality MRI to avoid DRE and as the first assessment for changes in PSA, with omission of repeat standard biopsy when PSA and MRI are stable. Development of a robust, dynamic, risk-adapted approach to surveillance is the highest research priority in AS for prostate cancer.

PATIENT SUMMARY

A diverse group of experts in active surveillance, including a broad range of health care professionals and researchers and those with lived experience of prostate cancer, agreed that best practice includes the use of high-quality magnetic resonance imaging, which can allow digital rectal examination and some biopsies to be omitted. The highest research priority in active surveillance research was identified as the development of a dynamic, risk-adjusted approach.

A Systematic Review of Heterogeneity in Outcome Definition and Reporting in Localised Renal Cancer

Context

Outcomes in renal cell carcinoma (RCC) are reported inconsistently, with variability in definitions and measurement. Hence, it is difficult to compare intervention effectiveness and synthesise outcomes for systematic reviews and to create clinical practice guidelines. This uncertainty in the evidence makes it difficult to guide patient-clinician decision-making. One solution is a core outcome set (COS): an agreed minimum set of outcomes.

Objective

To describe outcome reporting, definitions, and measurement heterogeneity as the first stage in co-creating a COS for localised renal cancer.

Evidence acquisition

We systematically reviewed outcome reporting heterogeneity in effectiveness trials and observational studies in localised RCC. In total, 2822 studies (randomised controlled trials, cohort studies, case-control studies, systematic reviews) up to June 2020 meeting our inclusion criteria were identified. Abstracts and full texts were screened independently by two reviewers; in cases of disagreement, a third reviewer arbitrated. Data extractions were double-checked.

Evidence synthesis

We included 149 studies and found that there was inconsistency in which outcomes were reported across studies and variability in the definitions used for outcomes that were conceptually the same. We structured our analysis using the outcome classification taxonomy proposed by Dodd et al. Outcomes linked to adverse events (eg, bleeding, outcomes linked to surgery) and renal injury outcomes (reduced renal function) were reported most commonly. Outcomes related to deaths from any cause and from cancer were reported in 44% and 25% of studies, respectively, although the time point for measurement and the analysis methods were inconsistent. Outcomes linked to life impact (eg, global quality of life) were reported least often. Clinician-reported outcomes are more frequently reported than patient-reported outcomes in the renal cancer literature.

Conclusions

This systematic review underscores the heterogeneity of outcome reporting, definitions, and measurement in research on localised renal cancer. It catalogues the variety of outcomes and serves as a first step towards the development of a COS for localised renal cancer.

Patient summary

We reviewed studies on localised kidney cancer and found that multiple terms and definitions have been used to describe outcomes. These are not defined consistently, and often not defined at all. Our review is the first phase in developing a core outcome set to allow better comparisons of studies to improve medical care.

Developing a consensus statement for psychosocial support in active surveillance for prostate cancer

Purpose

Our objective was to prioritise the psychosocial support needs of men on active surveillance for prostate cancer and to develop a consensus statement to provide guidance on best practice psychosocial support for men choosing active surveillance and their families.

Subjects and methods

We undertook a patient and public involvement Delphi process over two rounds, informed by qualitative data and a comprehensive literature review, to prioritise the information and support needs of men on active surveillance for prostate cancer. Two panels were surveyed, a patient/carer panel (n = 55) and a health care provider panel (n = 114). Based on the findings of the Delphi surveys, an expert active surveillance discussion group developed a consensus statement to guide best practice.

Results

Patients and health care professionals differed slightly in their ideas concerning priorities for active surveillance psychosocial support. Broadly, agreed priority areas included -patients being involved in decision-making, continuity of care, more streamlined access to health care teams, improved understanding of the risk of prostate cancer progression and information and support provided through both health care professionals and peers. Based on the identified priorities, the expert discussion group agreed on 22 consensus statements for best practice in psychosocial care for active surveillance in respect of (1) principles of an active surveillance programme; (2) structure of consultations; (3) content of information and support; and (4) delivery of information.

Conclusion

This consensus statement provides a framework for patient-focused psychosocial support, which, if adopted, should increase uptake and adherence to active surveillance among men with prostate cancer.

Understanding reasons for non-adherence to active surveillance for low-intermediate risk prostate cancer

Background

Active surveillance (AS) is recommended by most national medical organizations as the preferred treatment option for men with low-risk prostate cancer (PCa). However, studies report that up to one third of men on AS dropout within 5 years, without evidence of disease progression. Despite high dropout rates, few studies have purposively explored the opinions and experiences of men who discontinued AS. The aim of this study was to gain insight into the reasons why some men on AS for PCa discontinue active treatment without evidence of disease progression.

Methods

Semi-structured interviews were undertaken with 14 men from diverse socio-cultural backgrounds who had been on AS for PCa but dropped out of surveillance to undergo active treatment without signs of disease progression. Purposive sampling to reach data saturation was used to select participants based on their experience of AS and willingness to share their experiences. Interviews were transcribed and analysis undertaken in an inductive thematic manner.

Results

The following themes arose from interviews as factors that potentially influence adherence to AS: men’s experience at diagnosis and follow-up consultations, involvement in shared decision-making, the extent of supportive care and information, administrative procedures and support from partner and peers. A poor experience during diagnosis could adversely influence long-term adherence to AS, given the same diagnostic tests are frequently repeated. The provision of consistent information and support while on AS, similar to that offered to men undergoing radical treatment, was also highlighted as being important to increase confidence in the process.

Conclusions

Effective communications skills among health professionals, aimed at building trust in patient-clinician relationships, providing opportunities for shared decision-making and developing self-efficacy, along with structured information and support, are key to enhancing long-term adherence to AS.

Is there any association between prostate-specific antigen screening frequency and uptake of active surveillance in men with low or very low risk prostate cancer?

BACKGROUND

Patient-related factors such as concern about cancer are believed to influence both men's decisions to undergo prostate specific antigen (PSA) testing and to have definitive treatment if diagnosed with low risk prostate cancer (PCa). The potential link between screening frequency and choice of active surveillance (AS) for low risk disease has not been studied previously. Our aim was to investigate whether there is any association between PCa screening frequency or previous negative prostate biopsy and uptake of AS among men with low risk PCa.

METHODS

This register-based study included all men ≤75 years from Stockholm who were diagnosed with low risk PCa from 2008 to 2014 (n = 4336). Pre-diagnostic PSA testing and biopsy histories were obtained from the Stockholm PSA and Biopsy Register, a population-based register for the Stockholm country. The association between previous screening/biopsy history and AS uptake (based on primary treatment recorded in the National Prostate Cancer Register) was examined using multivariable logistic regression.

RESULTS

Forty seven percent of men with low risk PCa underwent AS. Uptake was associated with older age, very low risk disease, more recent diagnosis and absence of family history. None of the screening/biopsy measures (testing frequency, mean interval, PSA velocity, highest pre-diagnostic PSA or prior negative biopsy) were associated with uptake of AS among men with low risk PCa. Generalisability to settings with different policies and practices may be limited.

CONCLUSION

We found no evidence that screening frequency and negative biopsy influence uptake of AS among Swedish men with low risk PCa. Further research is required to determine factors that still present barriers for men taking up AS.

A Single Educational Seminar Increases Confidence and Decreases Dropout from Active Surveillance by 5 Years After Diagnosis of Prostate Cancer

BACKGROUND

Researchers remain divided on the major causes of dropout from active surveillance (AS), with rates of up to 38% among men with no evidence of prostate cancer (PC) progression.

OBJECTIVE

To develop and evaluate an educational intervention in terms of adherence to AS among men with low- to intermediate-risk PC.

DESIGN, SETTING, AND PARTICIPANTS

We first carried out focus group discussions with men who had remained on and dropped out of AS to inform an intervention to increase adherence to AS. A total of 255 consecutive men who had selected AS were then recruited to either standard care (written information and access to a nurse specialist) or standard care and the intervention.

INTERVENTION

An educational seminar was designed by patients and clinicians including information on imaging, biopsy techniques, understanding pathology, large AS cohorts - mortality and morbidity risk and diet and lifestyle advice.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The proportion of men dropping out of AS for reasons other than disease progression was assessed at 1 and 5yr after AS selection using multivariate logistic regression.

RESULTS AND LIMITATIONS

Common themes influencing decision-making by men on AS were identified: (1) clinical consistency; (2) information; and (3) lifestyle advice. Addition of an educational seminar led to significantly fewer men dropping out of AS: at 1 and 5yr the dropout rate was 25% and 42%, respectively, in the standard care group, compared to 11% and 22% (p=0.001) in the intervention group. In the intervention group, 18 men failed to attend the seminar.

CONCLUSIONS

The AS dropout rate was halved following a single educational seminar delivered to groups of men with intermediate- or low-risk PC, even at 5yr.

PATIENT SUMMARY

Men on active surveillance (AS) for prostate cancer feel more supported when provided with an educational seminar within 3 mo of their treatment choice. The seminar halved the number of men dropping-out of AS, even at 5yr.

Factors Influencing Men's Choice of and Adherence to Active Surveillance for Low-risk Prostate Cancer: A Mixed-method Systematic Review

CONTEXT

Despite support for active surveillance (AS) as a first treatment choice for men with low-risk prostate cancer (PC), this strategy is largely underutilised.

OBJECTIVE

To systematically review barriers and facilitators to selecting and adhering to AS for low-risk PC.

EVIDENCE ACQUISITION

We searched PsychINFO, PubMed, Medline 2000-now, Embase, CINAHL, and Cochrane Central databases between 2002 and 2017 using the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. The Purpose, Respondents, Explanation, Findings and Significance (PREFS) and Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) quality criteria were applied. Forty-seven studies were identified.

EVIDENCE SYNTHESIS

Key themes emerged as factors influencing both choice and adherence to AS: (1) patient and tumour factors (age, comorbidities, knowledge, education, socioeconomic status, family history, grade, tumour volume, and fear of progression/side effects); (2) family and social support; (3) provider (speciality, communication, and attitudes); (4) healthcare organisation (geography and type of practice); and (5) health policy (guidelines, year, and awareness).

CONCLUSIONS

Many factors influence men's choice and adherence to AS on multiple levels. It is important to learn from the experience of other chronic health conditions as well as from institutions/countries that are making significant headway in appropriately recruiting men to AS protocols, through standardised patient information, clinician education, and nationally agreed guidelines, to ultimately decrease heterogeneity in AS practice.

PATIENT SUMMARY

We reviewed the scientific literature for factors affecting men's choice and adherence to active surveillance (AS) for low-risk prostate cancer. Our findings suggest that the use of AS could be increased by addressing a variety of factors such as information, psychosocial support, clinician education, and standardised guidelines.

Active surveillance for prostate cancer: a systematic review of contemporary worldwide practices

In the last decade, active surveillance (AS) has emerged as an acceptable choice for low-risk prostate cancer (PC), however there is discordance amongst large AS cohort studies with respect to entry and monitoring protocols. We systematically reviewed worldwide AS practices in studies reporting ≥5 years follow-up. We searched PubMed and Medline 2000-now and identified 13 AS cohorts. Three key areas were identified: (I) patient selection; (II) monitoring protocols; (III) triggers for intervention—(I) all studies defined clinically localised PC diagnosis as T2b disease or less and most agreed on prostate-specific antigen (PSA) threshold (<10 µg/L) and Gleason score threshold (3+3). Inconsistency was most notable regarding pathologic factors (e.g., number of positive cores); (II) all agreed on PSA surveillance as crucial for monitoring, and most agreed that confirmatory biopsy was required within 12 months of initiation. No consensus was reached on optimal timing of digital rectal examination (DRE), general health assessment or re-biopsy strategies thereafter; (III) there was no universal agreement for intervention triggers, although Gleason score, number or percentage of positive cancer cores, maximum cancer length (MCL) and PSA doubling time were used by several studies. Some also used imaging or re-biopsy. Despite consistent high progression-free/cancer-free survival and conversion-to-treatment rates, heterogeneity exists amongst these large AS cohorts. Combining existing evidence and gathering more long-term evidence [e.g., the Movember’s Global AS database or additional information on use of magnetic resonance imaging (MRI)] is needed to derive a broadly supported guideline to reduce variation in clinical practice.

Aiming for a holistic integrated service for men diagnosed with prostate cancer - Definitions of standards and skill sets for nurses and allied healthcare professionals

PURPOSE

To establish a comprehensive set of recommendations for the service structure and skill set of nurses and allied healthcare professionals in prostate cancer care.

METHODS

Using components of formal consensus methodology, a 30-member multidisciplinary panel produced 53 items for discussion relating to the provision of care for prostate cancer patients by specialist nurses and allied healthcare professionals. Items were developed by two rounds of email correspondence in which, first, items were generated and, second, items refined to form the basis of a consensus meeting which constituted the third round of review. The fourth and final round was an email review of the consensus output.

RESULTS

The panel agreed on 33 items that were appropriate for recommendations to be made. These items were grouped under categories of "Environment" and "Patient Pathway" and included comments on training, leadership, communication and quality assessment as well as specific items related to prostate diagnosis clinics, radical treatment clinics and follow-up survivor groups.

CONCLUSIONS

Specialist nurses and allied healthcare professionals play a vital role alongside urologists and oncologists to provide care to men with prostate cancer and their families. We present a set of standards and consensus recommendations for the roles and skill-set required for these practitioners to provide gold-standard prostate cancer care. These recommendations could form the basis for development of comprehensive integrated prostate cancer pathways in prostate cancer centres as well as providing guidance for any units treating men with prostate cancer.

A study to identify subjective gaps in survivorship knowledge of health care professionals in London

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Background: The London Cancer Alliance (LCA), created in 2011, is an integrated cancer system consisting of 14 NHS organisations serving a population of 5.7 million. The multi-professional Survivorship Pathway Group aims to improve the outcomes of adults living with and beyond cancer. Methods: A 14-15 point questionnaire was developed to identify gaps in survivorship knowledge of oncology health care professionals (HCP) working in London. We were interested in HCP’s knowledge of the existence of the Recovery Package (Holistic Needs Assessment and care plan, Treatment Summary, access to a Health and Wellbeing Event and Cancer Care Review). The survey was uploaded onto Smart Survey and sent to 434 HCPs. Results: 167 surveys were anonymously completed. The distribution of respondents included Clinical Nurse Specialists(CNS), physiotherapists, dieticians, oncologists. The majority of respondents worked in specialist centers (44%), with 35% working in acute secondary care, 27% in acute tertiary care and 6% in the community. HCPs from all tumour groups were represented, though breast cancer and head and neck cancer were best represented. The majority of respondents were familiar with some or all of the components of the Recovery Package (80%). HCPs were most confident when asking about anxiety/depression (83%) but least confident or confident to some extent asking about changes in cognitive function (49%) and bone health (49%). When addressing needs, HCPs were confident addressing fatigue (47%) but less confident addressing cardiac complications (65%) and sexual concerns (64%). CNSs in particular were confident asking and addressing most concerns but many were not confident or were only somewhat confident addressing menopausal symptoms (34%) or lymphedema (37%). Further training was identified in psychological support, sexual consequences and management of long-term side effects. The predominant research priority identified was long-term side effects. Conclusions: Data from this survey will inform local educational fora, service mapping studies and the LCA Survivorship Research Group’s future strategy.

Proteomic detection of PhoPQ- and acid-mediated repression of Salmonella motility

Salmonella adaptation to low pH is a critical survival response and essential for virulence. Here, we show that another key virulence-associated process, flagella-mediated cell motility, is co-regulated by low pH via the PhoPQ signal transduction system. Using a proteomic approach, we found that phase 1 and phase 2 flagellin were specifically down-regulated when acid-adapted (pH 5.0) Salmonella SL1344 cells were exposed to pH 3.0. Decreased flagellin expression and cell motility was dependent on activation of the PhoPQ pathway, which directly or indirectly negatively regulated transcription of the flagellin gene fliC. In contrast, the general stress sigma factor RpoS (sigma s) positively regulated flagellar gene expression. Low external pH had no effect on the level of H-NS protein, a further regulator of flagellar gene expression. We suggest that flagellar repression at low pH conserves ATP for survival processes and helps to limit the influx of protons into the cytosol. These results highlight the power of proteomics to reveal unanticipated links between relatively well-characterised regulatory systems in bacteria.

Prospective study of the usefulness of sural nerve biopsy

OBJECTIVE

This study aimed to determine the usefulness of sural nerve biopsy in neurological practice.

METHODS

The first prospective study of sural nerve biopsy in 50 consecutive patients was undertaken. The investigating neurologist declared the prebiopsy diagnosis and management plan and after 3 months an independent neurologist evaluated the contribution of the biopsy to diagnosis and management. An independent audit officer sought information from the patient about the adverse effects and value of the biopsy after 6 weeks and 6 months.

RESULTS

In seven cases the nerve biopsy changed the diagnosis, in 35 cases the biopsy confirmed the suspected diagnosis, and in eight cases the biopsy was non-contributory. The biopsy either changed or was helpful in guiding patient management in 60%, especially those with demyelinating neuropathy and multiple mononeuropathy. Seven patients reported having had infection and 10 reported increased pain at the biopsy site 6 months later.

CONCLUSION

In a consecutive series of 50 cases, sural nerve biopsy altered the diagnosis in 14%, affected management in 60%, and caused persistent increased pain at the biopsy site in 33%.

The analysis of microbial proteomes: strategies and data exploitation

Microbes present special opportunities for proteomic analysis that are not yet available for other types of organisms, due mainly to the relative abundance of information on their genomes, their low levels of functional redundancy and their experimental tractability. They are also being used to develop and validate powerful new experimental approaches that surmount some important current limitations in this field. The review surveys the different proteomic procedures that are available and considers the advantages and disadvantages of different experimental strategies. The ways in which microbiologists - and others - can exploit proteomic data are also discussed.

Formate protects stationary-phase Escherichia coli and Salmonella cells from killing by a cationic antimicrobial peptide

For a sustained infection, enteric bacterial pathogens must evade, resist or tolerate a variety of antimicrobial host defence peptides and proteins. We report here that specific organic acids protect stationary-phase Escherichia coli and Salmonella cells from killing by a potent antimicrobial peptide derived from the human bactericidal/permeability-increasing protein (BPI). BPI-derived peptide P2 rapidly halted oxygen consumption by stationary-phase cells preincubated with glucose, pyruvate or malate and caused a 109-fold drop in cell viability within 90 min of addition. In marked contrast, O2 consumption and viability were not significantly affected in stationary-phase cells preincubated with formate or succinate. Experiments with fdhH, fdoG, fdnG, selC and sdhO mutants indicate that protection by formate and succinate requires their oxidation by the Fdh-N formate dehydrogenase and succinate dehydrogenase respectively. Protection was also dependent on the BipA GTPase but did not require the RpoS sigma factor. We conclude that the primary lesion caused by this cationic peptide is not gross permeabilization of the bacterial cytoplasmic membrane but may involve specific disruption of the respiratory chain. Because P2 shares sequence similarity with a range of other antimicrobial peptides, its cytotoxic mechanism has broader significance. Additionally, protective quantities of formate are secreted by E. coli and Salmonella during growth suggesting that such compounds are important determinants of bacterial survival in the host.

Defining protease specificity with proteomics: a protease with a dibasic amino acid recognition motif is regulated by a two-component signal transduction system in Salmonella

Microbial proteases play diverse and important roles in bacterial virulence but their detection and characterisation is often hampered by their limited abundance or lack of expression in the absence of suitable environmental signals. We describe here a sensitive proteomic approach to detect proteases that are under the control of a virulence regulator and to characterise their recognition motifs. Using MG++-depleted growth media or a mutant strain of Salmonella in which the PhoP-PhoQ virulence regulatory system is constitutively active, truncated forms of DnaK, elongation factor G, elongation factor Tu and ribosomal protein S1 proteins were detected. Two other global regulatory mutants and cells exposed to acid or to oxidative stress failed to produce the truncated proteins, indicating specific control of the protease activity by the PhoP-PhoQ system. Our results suggest that at least two proteases are induced. To define the proteolytic cleavage sites of one of the proteases, peptides from each of the truncated proteins were identified by tryptic mass fingerprinting/nanoelectrospray mass spectrometry and mapped onto the sequence of the intact protein. Alignment of the regions around the cut site indicates that the protease recognises a dibasic amino acid motif characteristic of the omptin protease family. The induction of such proteases in bacteria depleted of Mg++ ions may contribute to the PhoPQ-mediated resistance of Salmonella to cationic antimicrobial peptides. Additionally, our results suggest it would be prudent to keep the concentration of this ion above micromolar levels during bacterial sample preparation for proteomic analyses.

The flgE gene of Campylobacter coli is under the control of the alternative sigma factor sigma54

The flgE gene encoding the flagellar hook protein of Campylobacter coli VC167-T1 was cloned by immunoscreening of a genomic library constructed in lambdaZAP Express. The flgE DNA sequence was 2,553 bp in length and encoded a protein with a deduced molecular mass of 90,639 Da. The sequence had significant homology to the 5' and 3' sequences of the flgE genes of Helicobacter pylori, Treponema phagedenis, and Salmonella typhimurium. Primer extension analysis indicated that the VC167 flgE gene is controlled by a sigma54 promoter. PCR analysis showed that the flgE gene size and the 5' and 3' DNA sequences were conserved among C. coli and C. jejuni strains. Southern hybridization analyses confirmed that there is considerable sequence identity among the hook genes of C. coli and C. jejuni but that there are also regions within the genes which differ. Mutants of C. coli defective in hook production were generated by allele replacement. These mutants were nonmotile and lacked flagellar filaments. Analyses of flgE mutants indicated that the carboxy terminus of FlgE is necessary for assembly of the hook structure but not for secretion of FlgE and that, unlike salmonellae, the lack of flgE expression does not result in repression of flagellin expression.

Characterization of a post-translational modification of Campylobacter flagellin: identification of a sero-specific glycosyl moiety

The flagellins of Campylobacter spp. differ antigenically. In variants of C. coli strain VC167, two antigenic flagellin types determined by sero-specific antibodies have been described (termed T1 and T2). Post-translational modification has been suggested to be responsible for T1 and T2 epitopes, and, using mild periodate treatment and biotin hydrazide labelling, flagellin from both VC167-T1 and T2 were shown to be glycosylated. Glycosylation was also shown to be present on other Campylobacter flagellins. The ability to label all Campylobacter flagellins examined with the lectin LFA demonstrated the presence of a terminal sialic acid moiety. Furthermore, mild periodate treatment of the flagellins of VC167 eliminated reactivity with T1 and T2 specific antibodies LAH1 and LAH2, respectively, and LFA could also compete with LAH1 and LAH2 antibodies for binding to their respective flagellins. These data implicate terminal sialic acid as part of the LAH strain-specific epitopes. However, using mutants in genes affecting LAH serorecognition of flagellin it was demonstrated that sialic acid alone is not the LAH epitope. Rather, the epitope(s) is complex, probably involving multiple glycosyl and/or amino acid residues.

Identification and characterization of genes required for post-translational modification of Campylobacter coli VC167 flagellin

Two genes have been identified in Campylobacter coli VC167 which are required for the biosynthesis of post-translational modifications on flagellin proteins. The ptmA gene encodes a protein of predicted M(r) 28,486 which shows significant homology to a family of alcohol dehydrogenases from a variety of bacteria. The ptmB gene encodes a protein of predicted M(r) 26,598 with significant homology to CMP-N-acetylneuraminic acid synthetase enzymes involved in sialic acid capsular biosynthesis in Neisseria meninigitidis and Escherichia coli K1. Site-specific mutation of either ptmA or ptmB caused loss of reactivity with antisera specific to the post-translational modifications and a change in the isoelectric focusing fingerprints relative to the parent strains. Mutation of ptmB, but not of ptmA, caused a change in apparent M(r) of the flagellin subunit in SDS-PAGE gels. The ptmA and ptmB genes are present in other strains of Campylobacter. In a rabbit model the ptmA mutant showed a reduced ability to elicit protection against subsequent challenge with heterologous strains of the same Lior serotype compared to the parental wild-type strain. This suggests that the surface-exposed post-translational modifications may play a significant role in the protective immune response.

Sensory integration and play behavior

This paper presents a case study describing a developmentally delayed child and examines the changes in environmental interactions that occurred during a study period in occupational therapy in which sensory integration (SI) techniques were applied. Its purpose is to discuss the use of play observation as a means of measuring change in individuals involved in SI treatment and to demonstrate the relevance of qualitative research methodologies to the collection of data on play behavior. The study is a first step in a process of developing methods to evaluate the effectiveness of SI treatment in occupational therapy through collecting qualitative data on play and other behavioral measures of environmental interactions.