Oligopeptide Signaling through TbGPR89 Drives Trypanosome Quorum Sensing.

Trypanosome parasites control their virulence and spread by using quorum sensing (QS) to generate transmissible "stumpy forms" in their host bloodstream. However, the QS signal "stumpy induction factor" (SIF) and its reception mechanism are unknown. Although trypanosomes lack G protein-coupled receptor signaling, we have identified a surface GPR89-family protein that regulates stumpy formation. TbGPR89 is expressed on bloodstream "slender form" trypanosomes, which receive the SIF signal, and when ectopically expressed, TbGPR89 drives stumpy formation in a SIF-pathway-dependent process. Structural modeling of TbGPR89 predicts unexpected similarity to oligopeptide transporters (POT), and when expressed in bacteria, TbGPR89 transports oligopeptides. Conversely, expression of an E. coli POT in trypanosomes drives parasite differentiation, and oligopeptides promote stumpy formation in vitro. Furthermore, the expression of secreted trypanosome oligopeptidases generates a paracrine signal that accelerates stumpy formation in vivo. Peptidase-generated oligopeptide QS signals being received through TbGPR89 provides a mechanism for both trypanosome SIF production and reception.

Digitally monitored inhaled therapy: a 'smart' way to manage severe asthma?

INTRODUCTION: One of the fundamental challenges of managing patients with severe asthma is treatment adherence, particularly with inhaled corticosteroids. Adherence is difficult to measure objectively and poor adherence is associated with worse outcomes. In this study, assess the ability of a 'smart' inhaler to record adherence in severe asthma patients and measure the impact of this on asthma control. METHODS: Consecutive consenting patients meeting criteria for biologics had their existing high-dose ICS/LABA//LAMA combination inhaler/s switched to mometasone/indacaterol/glycopyrronium (114/46/136). Routine clinical data, including blood eosinophils, FeNO, and ACQ-6 scores were collected at baseline and at 4 wk. Adherence was then checked on the Propeller Health app, and good adherence was defined as >80% of prescribed usage. Participants were then followed-up at 12 months to record the proportion of patients who were initiated on biologics. RESULTS: 77 patients (mean [SD] age = 50.4 [15.7] years, 67.5% female [n = 52]) participated. 71 participants were able to use the device and 65% (n = 46) of these attained good asthma control and were not initiated on biologics at 12-month follow-up. Both groups demonstrated a significant reduction in ACQ6 score at follow-up (2.81 vs. 1.92, p < 0.001 and 3.05 vs. 2.60, p < 0.001, respectively), but there was no statistically significant difference in improvement between groups. Patients with optimal adherence also demonstrated a significant reduction in median FeNO at follow-up (47 ppb vs. 40 ppb, p = 0.003). CONCLUSIONS: In severe asthma patients, 'smart' inhalers may represent an effective management tool to improve adherence and asthma control, therefore avoiding the need for patients to commence biological therapies.

Induction of an IL7-R(+)c-Kit(hi) myelolymphoid progenitor critically dependent on IFN-gamma signaling during acute malaria.

Although the relationship between hematopoietic stem cells and progenitor populations has been investigated extensively under steady-state conditions, the dynamic response of the hematopoietic compartment during acute infection is largely unknown. Here we show that after infection of mice with Plasmodium chabaudi, a c-Kit(hi) progenitor subset positive for interleukin 7 receptor-alpha (IL-7Ralpha) emerged that had both lymphoid and myeloid potential in vitro. After being transferred into uninfected alymphoid or malaria-infected hosts, IL-7Ralpha(+)c-Kit(hi) progenitors generated mainly myeloid cells that contributed to the clearance of infected erythrocytes in infected hosts. The generation of these infection-induced progenitors was critically dependent on interferon-gamma (IFN-gamma) signaling in hematopoietic progenitors. Thus, IFN-gamma is a key modulator of hematopoiesis and innate and adaptive immunity during acute malaria infection.

Objective Assessment of Cough: An Early Marker of Response to Biological Therapies in Asthma?

Cough is an important symptom of asthma. The objective assessment of chronic cough has been enhanced by the development of ambulatory cough monitoring systems. Mepolizumab has been demonstrated to reduce exacerbations in eosinophilic asthmatics long-term. We evaluate the utility of objective cough count as an outcome measure in severe eosinophilic asthma treated with mepolizumab. Consecutive, consenting patients initiated on treatment with mepolizumab had a 24-h cough count recorded at baseline; this was repeated at 1, 3 and 6 months. Asthma control questionnaire (ACQ) scores and exacerbation frequency were also recorded. The mean 24-h cough count in 11 subjects (8 females, mean age 53.6 years) was 172.4 at baseline; at 1, 3 and 6 months following initiation of treatment this decreased to 101.4, 92 and 70.8, respectively (p < 0.02). Significant improvements were also observed in mean ACQ score (3-1.6, p < 0.01) and exacerbation frequency (5.5 per year - 1.3, p < 0.01). Objective cough measurement could be used as an early, precise and clinically relevant endpoint in assessing response to asthma therapy.

Identification of candidate transmission-blocking antigen genes in Theileria annulata and related vector-borne apicomplexan parasites.

BACKGROUND: Vector-borne apicomplexan parasites are a major cause of mortality and morbidity to humans and livestock globally. The most important disease syndromes caused by these parasites are malaria, babesiosis and theileriosis. Strategies for control often target parasite stages in the mammalian host that cause disease, but this can result in reservoir infections that promote pathogen transmission and generate economic loss. Optimal control strategies should protect against clinical disease, block transmission and be applicable across related genera of parasites. We have used bioinformatics and transcriptomics to screen for transmission-blocking candidate antigens in the tick-borne apicomplexan parasite, Theileria annulata. RESULTS: A number of candidate antigen genes were identified which encoded amino acid domains that are conserved across vector-borne Apicomplexa (Babesia, Plasmodium and Theileria), including the Pfs48/45 6-cys domain and a novel cysteine-rich domain. Expression profiling confirmed that selected candidate genes are expressed by life cycle stages within infected ticks. Additionally, putative B cell epitopes were identified in the T. annulata gene sequences encoding the 6-cys and cysteine rich domains, in a gene encoding a putative papain-family cysteine peptidase, with similarity to the Plasmodium SERA family, and the gene encoding the T. annulata major merozoite/piroplasm surface antigen, Tams1. CONCLUSIONS: Candidate genes were identified that encode proteins with similarity to known transmission blocking candidates in related parasites, while one is a novel candidate conserved across vector-borne apicomplexans and has a potential role in the sexual phase of the life cycle. The results indicate that a 'One Health' approach could be utilised to develop a transmission-blocking strategy effective against vector-borne apicomplexan parasites of animals and humans.

The impact of surgery for vulval cancer upon health-related quality of life and pelvic floor outcomes during the first year of treatment: a longitudinal, mixed methods study.

OBJECTIVE: To measure the long-term impact of surgical treatment for vulval cancer upon health-related quality of life and pelvic floor outcomes during the first year of therapy. METHODS: Prospective, longitudinal, mixed-methods study. Twenty-three women aged >18 years with a new diagnosis of vulval cancer were recruited. The EORTC QLQ C30, SF-36 and an electronic pelvic floor assessment questionnaire (ePAQ-PF) were administered at baseline (pre-treatment) and 3, 6, 9 and 12 months post-treatment. Mixed effects repeated measures models (all adjusted for age and BMI) were used to investigate changes over time and differences between cancer stage. Qualitative interviews were carried out with 11 of the women and analysed using a thematic approach. RESULTS: Mean age was 59.9 years (SD = 15.3; range = 23.8-86.6 yrs). Mean BMI was 30.0 (SD = 4.5; range = 24.4-38.2). Sixteen women had early (Stage 1 to 2B), and seven women had advanced stage disease (Stage 3 to 4B). Questionnaire scores revealed that physical and social functioning, fatigue, pain and general sex life were significantly worse at 12 months than pre-treatment (p = < 0.05). Qualitative analysis revealed multiple treatment side effects which were perceived as severe and enduring. Women with advanced vulval cancer had significantly worse SF-36 mental health scores at 12 months compared to women with early stage disease (p = 0.037). CONCLUSIONS: Surgery for vulval cancer has long-term implications which can be persistent 12 months post-treatment. High rates of morbidity relating to lymphoedema and sexual function re-enforce the need for specialist clinics to support women who suffer these complications. © 2015 The Authors. Psycho-Oncology published by John Wiley & Sons Ltd.

Sequestration and histopathology in Plasmodium chabaudi malaria are influenced by the immune response in an organ-specific manner.

Infection with the malaria parasite, Plasmodium, is associated with a strong inflammatory response and parasite cytoadhesion (sequestration) in several organs. Here, we have carried out a systematic study of sequestration and histopathology during infection of C57Bl/6 mice with Plasmodium chabaudi AS and determined the influence of the immune response. This parasite sequesters predominantly in liver and lung, but not in the brain, kidney or gut. Histopathological changes occur in multiple organs during the acute infection, but are not restricted to the organs where sequestration takes place. Adaptive immunity, and signalling through the IFNγ receptor increased sequestration and histopathology in the liver, but not in the lung, suggesting that there are differences in the adhesion molecules and/or parasite ligands utilized and mechanisms of pathogenesis in these two organs. Exacerbation of pro-inflammatory responses during infection by deletion of the il10 gene resultsin the aggravation of damage to lung and kidney irrespective of the degree of sequestration. The immune response therefore affected both sequestration and histopathology in an organ-specific manner. P. chabaudi AS provides a good model to investigate the influence of the host response on the sequestration and specific organ pathology, which is applicable to human malaria.

Nurse practitioners changing health behaviours: one patient at a time.

In 2005, legislation was enacted allowing nurse practitioners (NPs) to practise in British Columbia, Canada. Although substantial human and financial resources had been dedicated to the implementation of the role, no evaluation has been conducted to date. As part of a larger multiphase, mixed-methods study design, which evaluated the integration of NPs into the British Columbia healthcare system, this article describes findings related to changes that result for patients and the implications for the healthcare system when NPs become part of the care process. Using survey and interview data, themes that emerged were patient satisfaction, access to care, and behavioural changes. Findings suggest that patients are satisfied with the care they receive from NPs and that NPs make positive changes to health behaviour.

Shared decision-making in advanced physiotherapy and first contact physiotherapy management of adults with musculoskeletal disorders in the United Kingdom: An online cross-sectional survey.

RATIONALE: Advanced practice physiotherapy roles (Advanced Physiotherapy Practitioners [APPs] and First Contact Physiotherapists [FCPs]) are pivotal in supporting patients to manage their musculoskeletal (MSK) conditions. Having a greater understanding of how decisions are made by these practitioners will inform competency frameworks and improve the provision of patient-centred care. AIM: To evaluate the current knowledge, views and use of shared decision-making in MSK advanced physiotherapy practice in the United Kingdom. METHODS: A cross-sectional survey using an online questionnaire was used to collect demographic information, knowledge, views and self-reported use of shared decision-making (SDM) of APPs and FCPs who work with adults with MSK disorders in the United Kingdom. RESULTS: Responses from 49 participants (25 APPs and 24 FCPs) were included in the study. In total, 80% of participants had received SDM training and overall high levels of knowledge were shown. Only 12% of participants used a communication model to facilitate SDM. In total, 80% of participants reported making decisions together with the patient either always or most of the time. FCPs favoured a more patient-led approach to decision-making compared to APPs who favoured collaborative decision-making. The most commonly reported barriers to SDM included lack of time, lack of patient education resources, lack of access to patient decision aids and treatment pathway restrictions. CONCLUSIONS: The responses in this study showed that overall APPs and FCPs have good knowledge of SDM and report routine use of collaborative and patient-led decision-making approaches.

Lower urinary tract symptoms in men: the TRIUMPH cluster RCT.

Background: Conservative therapies are recommended as initial treatment for male lower urinary tract symptoms. However, there is a lack of evidence on effectiveness and uncertainty regarding approaches to delivery. Objective: The objective was to determine whether or not a standardised and manualised care intervention delivered in primary care achieves superior symptomatic outcome for lower urinary tract symptoms to usual care. Design: This was a two-arm cluster randomised controlled trial. Setting: The trial was set in 30 NHS general practice sites in England. Participants: Participants were adult men (aged ≥ 18 years) with bothersome lower urinary tract symptoms. Interventions: Sites were randomised 1 : 1 to deliver the TReatIng Urinary symptoms in Men in Primary Health care using non-pharmacological and non-surgical interventions trial intervention or usual care to all participants. The TReatIng Urinary symptoms in Men in Primary Health care using non-pharmacological and non-surgical interventions intervention comprised a standardised advice booklet developed for the trial from the British Association of Urological Surgeons' patient information sheets, with patient and expert input. Patients were directed to relevant sections by general practice or research nurses/healthcare assistants following urinary symptom assessment, providing the manualised element. The healthcare professional provided follow-up contacts over 12 weeks to support adherence to the intervention. Main outcome measures: The primary outcome was the validated patient-reported International Prostate Symptom Score 12 months post consent. Rather than the minimal clinically important difference of 3.0 points for overall International Prostate Symptom Score, the sample size aimed to detect a difference of 2.0 points, owing to the recognised clinical impact of individual symptoms. Results: A total of 1077 men consented to the study: 524 in sites randomised to the intervention arm (n = 17) and 553 in sites randomised to the control arm (n = 13). A difference in mean International Prostate Symptom Score at 12 months was found (adjusted mean difference of -1.81 points, 95% confidence interval -2.66 to -0.95 points), with a lower score in the intervention arm, indicating less severe symptoms. Secondary outcomes of patient-reported urinary symptoms, quality of life specific to lower urinary tract symptoms and perception of lower urinary tract symptoms all showed evidence of a difference between the arms favouring the intervention. No difference was seen between the arms in the proportion of urology referrals or adverse events. In qualitative interviews, participants welcomed the intervention, describing positive effects on their symptoms, as well as on their understanding of conservative care and their attitude towards the experience of lower urinary tract symptoms. The interviews highlighted that structured, in-depth self-management is insufficiently embedded within general practitioner consultations. From an NHS perspective, mean costs and quality-adjusted life-years were similar between trial arms. The intervention arm had slightly lower mean costs (adjusted mean difference of -£29.99, 95% confidence interval -£109.84 to £22.63) than the usual-care arm, and a small gain in quality-adjusted life-years (adjusted mean difference of 0.001, 95% confidence interval -0.011 to 0.014). Conclusions: The intervention showed a small, sustained benefit for men's lower urinary tract symptoms and quality of life across a range of outcome measures in a UK primary care setting. Qualitative data showed that men highly valued the intervention. Intervention costs were marginally lower than usual-care costs. Limitations of the study included that trial participants were unmasked, with limited diversity in ethnicity and deprivation level. Additional research is needed to assess the applicability of the intervention for a more ethnically diverse population.. Trial registration: This trial is registered as ISRCTN11669964. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 16/90/03) and is published in full in Health Technology Assessment; Vol. 28, No. 13. See the NIHR Funding and Awards website for further award information.

Urinary problems among men become more common with age. Nearly one-third of all men aged > 65 years experience some urinary symptoms, which can have a substantial effect on their daily lives. Symptoms include needing to pass urine more often, urgently or during the night, and difficulties in passing urine. Men are usually diagnosed and treated by their general practitioner, and should be offered advice on controlling their symptoms themselves (e.g. lifestyle changes and exercises) before trying tablets or surgery. However, it is not known how helpful such advice is, and how general practices can effectively provide it. Thirty general practices in the West of England and Wessex took part in the study. Practices were split into two groups, with each practice providing either the TReatIng Urinary symptoms in Men in Primary Health care using non-pharmacological and non-surgical interventions care package or the practice's usual care to all of its patients in the trial. The TReatIng Urinary symptoms in Men in Primary Healthcare using nonpharmacological and non-surgical interventions care package included a booklet of advice to help control urinary symptoms, with a nurse or healthcare assistant directing men to relevant sections according to their symptoms, and providing follow-up contacts. We mainly assessed the benefits of the TReatIng Urinary symptoms in Men in Primary Healthcare using nonpharmacological and non-surgical interventions care package, compared with usual care, by using a questionnaire on urinary symptoms completed by participants. A total of 1077 men with urinary symptoms that bothered them joined the study. The main result was that men reported greater improvement in urinary symptoms with the TRIUMPH care package than with usual care, 12 months after joining the study. We also found that men receiving the TRIUMPH care package had a slight improvement in quality of life and outlook on their urinary symptoms. There was no difference between the two groups in the number of patients referred to hospital for treatment, the type, number and severity of side effects or cost to the NHS. Overall, the TRIUMPH care package was more effective in treating men with urinary symptoms than usual care by their general practice.

Levels of distress in breast cancer survivors approaching discharge from routine hospital follow-up.

BACKGROUND: Hospital-based breast cancer follow-up provides reassurance to patients despite limited evidence for clinical efficacy. Although alternative models of hospital/community-based follow-up have yielded encouraging results, traditional hospital follow-up continues to be offered to all patients. Survival rates continue to rise; consequently, more patients are likely to require support, as many have a limited understanding of the long-term physical and emotional consequences of cancer and its treatment. We examine levels of psychological distress in breast cancer patients in follow-up 2 years or more from diagnosis. METHODS: This prospective study measured psychological distress levels using standardized measures [Hospital Anxiety and Depression Scale (HADS), Clinical Outcomes for Routine Evaluation (CORE) and Measure Yourself Medical Outcomes Profile (MYMOP)]. Between January and September 2008, 323 consecutive patients were approached in outpatient clinics. Ninety-six patients declined to participate. RESULTS: Two hundred twenty-seven patients took home patient information sheets; 172 (75%) returned completed questionnaires to assess levels of distress (HADS, CORE). MYMOP provided self-reported data on patient symptoms. Patients reported low levels of distress in hospital-based follow-up, which were comparable or better than general population norms, although there was a significant minority of patients reporting high scores (n = 27, 15.7%) on HADS or CORE. There was good agreement between these two measures. All sub-scales of CORE (except risk) correlated well with HADS for anxiety/depression. No significant changes were detected in the standardized measures. MYMOP results showed that 23.8% of respondents reported both physical and emotional symptoms. CONCLUSIONS: Breast cancer survivors reported good psychological outcomes 2 years on from diagnosis. Screening for psychological/emotional distress is a vital part of follow-up care, which should be incorporated into UK policy.

Profiling disordered eating patterns and body mass index (BMI) in the English general population.

PURPOSE: Little national evidence exists on disordered eating patterns in the UK. This study examined the prevalence and nature of disordered eating patterns in the National Adult Psychiatric Morbidity Survey 2007. METHOD: Responses to the screening tool for eating disorders (SCOFF) and body mass index (BMI) were analysed using latent class analysis (n = 7,001). Multinomial logistic regression explored the associations between latent classes and mental health comorbidities. RESULTS: The prevalence of possible eating disorders in England using the SCOFF was 6.3 %; this decreased to 1.6 % when accounting for the negative impact feelings about food had on the respondent's life. Five latent classes were identified: classes 1 and 2 resembled known eating disorders ('marginal anorexia' relating to anorexia nervosa and 'binge eaters' relating to bulimia nervosa/binge eating disorder); class 3 consisted of people who were obese, but did not experience eating problems; class 4 was morbidly obese, with an elevated risk of anxiety disorders; class 5 was labelled as 'normal eaters', with a low probability of eating problems and a normal BMI. CONCLUSIONS: Adults assigned to eating disorder type classes are at increased risk for mental health comorbidities and poorer social functioning. Information presented herein on clustering of disordered eating patterns may help clinicians identify those men and women risk for an eating disorder.

Does a screening checklist for complex health and social care needs have potential clinical usefulness for predicting unplanned hospital readmissions in intensive care survivors: development and prospective cohort study.

OBJECTIVES: Intensive care (ICU) survivors are at high risk of long-term physical and psychosocial problems. Unplanned hospital readmission rates are high, but the best way to triage patients for interventions is uncertain. We aimed to develop and evaluate a screening checklist to help predict subsequent readmissions or deaths. DESIGN: A checklist for complex health and social care needs (CHSCNs) was developed based on previous research, comprising six items: multimorbidity; polypharmacy; frequent previous hospitalisations; mental health issues; fragile social circumstances and impaired activities of daily living. Patients were considered to have CHSCNs if two or more were present. We prospectively screened all ICU discharges for CHSCNs for 12 months. SETTING: ICU, Royal Infirmary, Edinburgh, UK. PARTICIPANTS: ICU survivors over a 12-month period (1 June 2018 and 31 May 2019). INTERVENTIONS: None. OUTCOME MEASURE: Readmission or death in the community within 3 months postindex hospital discharge. RESULTS: Of 1174 ICU survivors, 937 were discharged alive from the hospital. Of these 253 (27%) were classified as having CHSCNs. In total 28% (266/937) patients were readmitted (N=238) or died (N=28) within 3 months. Among CHSCNs patients 45% (n=115) patients were readmitted (N=105) or died (N=10). Patients without CHSCNs had a 22% readmission (N=133) or death (N=18) rate. The checklist had: sensitivity 43% (95% CI 37% to 49%), specificity 79% (95% CI 76% to 82%), positive predictive value 45% (95% CI 41% to 51%), and negative predictive value 78% (95% CI 76% to 80%). Relative risk of readmission/death for patients with CHSCNs was 2.06 (95% CI 1.69 to 2.50), indicating a pretest to post-test probability change of 28%-45%. The checklist demonstrated high inter-rater reliability (percentage agreement ≥87% for all domains; overall kappa, 0.84). CONCLUSIONS: Early evaluation of a screening checklist for CHSCNs at ICU discharge suggests potential clinical usefulness, but this requires further evaluation as part of a care pathway.

Intestinal inflammation and increased intestinal permeability in Plasmodium chabaudi AS infected mice.

Background: Gastrointestinal symptoms are commonly associated with acute Plasmodium spp infection. Malaria-associated enteritis may provide an opportunity for enteric pathogens to breach the intestinal mucosa, resulting in life-threatening systemic infections. Methods: To investigate whether intestinal pathology also occurs during infection with a murine model of mild and resolving malaria, C57BL/6J mice were inoculated with recently mosquito-transmitted Plasmodium chabaudi AS. At schizogony, intestinal tissues were collected for quantification and localisation of immune mediators and malaria parasites, by PCR and immunohistochemistry. Inflammatory proteins were measured in plasma and faeces and intestinal permeability was assessed by FITC-dextran translocation after oral administration. Results: Parasitaemia peaked at approx. 1.5% at day 9 and resolved by day 14, with mice experiencing significant and transient anaemia but no weight loss. Plasma IFN-γ, TNF-α and IL10 were significantly elevated during peak infection and quantitative RT-PCR of the intestine revealed a significant increase in transcripts for ifng and cxcl10. Histological analysis revealed parasites within blood vessels of both the submucosa and intestinal villi and evidence of mild crypt hyperplasia. In faeces, concentrations of the inflammatory marker lactoferrin were significantly raised on days 9 and 11 and FITC-dextran was detected in plasma on days 7 to 14. At day 11, plasma FITC-dextran concentration was significantly positively correlated with peripheral parasitemia and faecal lactoferrin concentration. Conclusions: In summary, using a relevant, attenuated model of malaria, we have found that acute infection is associated with intestinal inflammation and increased intestinal permeability. This model can now be used to explore the mechanisms of parasite-induced intestinal inflammation and to assess the impact of increased intestinal permeability on translocation of enteropathogens.

Migrating monocytes recruited to the spleen play an important role in control of blood stage malaria.

Host responses controlling blood-stage malaria include both innate and acquired immune effector mechanisms. During Plasmodium chabaudi infection in mice, a population of CD11b(high)Ly6C(+) monocytes are generated in bone marrow, most of which depend on the chemokine receptor CCR2 for migration from bone marrow to the spleen. In the absence of this receptor mice harbor higher parasitemias. Most importantly, splenic CD11b(high)Ly6C(+) cells from P chabaudi-infected wild-type mice significantly reduce acute-stage parasitemia in CCR2(-/-) mice. The CD11b(high)Ly6C(+) cells in this malaria infection display effector functions such as production of inducible nitric oxide synthase and reactive oxygen intermediates, and phagocytose P chabaudi parasites in vitro, and in a proportion of the cells, in vivo in the spleen, suggesting possible mechanisms of parasite killing. In contrast to monocyte-derived dendritic cells, CD11b(high)Ly6C(+) cells isolated from malaria-infected mice express low levels of major histocompatibility complex II and have limited ability to present the P chabaudi antigen, merozoite surface protein-1, to specific T-cell receptor transgenic CD4 T cells and fail to activate these T cells. We propose that these monocytes, which are rapidly produced in the bone marrow as part of the early defense mechanism against invading pathogens, are important for controlling blood-stage malaria parasites.

Plasmodium Cysteine Repeat Modular Proteins 3 and 4 are essential for malaria parasite transmission from the mosquito to the host.

BACKGROUND: The Plasmodium Cysteine Repeat Modular Proteins (PCRMP) are a family of four conserved proteins of malaria parasites, that contain a number of motifs implicated in host-parasite interactions. Analysis of mutants of the rodent parasite Plasmodium berghei lacking expression of PCRMP1 or 2 showed that these proteins are essential for targeting of P. berghei sporozoites to the mosquito salivary gland and, hence, for transmission from the mosquito to the mouse. METHODS: In this work, the role of the remaining PCRMP family members, PCRMP3 and 4, has been investigated throughout the Plasmodium life cycle by generation and analysis of P. berghei gene deletion mutants, Δpcrmp3 and Δpcrmp4. The role of PCRMP members during the transmission and hepatic stages of the Plasmodium lifecycle has been evaluated by light- and electron microscopy and by analysis of liver stage development in HEPG2 cells in vitro and by infecting mice with mutant sporozoites. In addition, mice were immunized with live Δpcrmp3 and Δpcrmp4 sporozoites to evaluate their immunization potential as a genetically-attenuated parasite-based vaccine. RESULTS: Disruption of pcrmp3 and pcrmp4 in P. berghei revealed that they are also essential for transmission of the parasite through the mosquito vector, although acting in a distinct way to pbcrmp1 and 2. Mutants lacking expression of PCRMP3 or PCRMP4 show normal blood stage development and oocyst formation in the mosquito and develop into morphologically normal sporozoites, but these have a defect in egress from oocysts and do not enter the salivary glands. Sporozoites extracted from oocysts perform gliding motility and invade and infect hepatocytes but do not undergo further development and proliferation. Furthermore, the study shows that immunization with Δcrmp3 and Δcrmp4 sporozoites does not confer protective immunity upon subsequent challenge. CONCLUSIONS: PCRMP3 and 4 play multiple roles during the Plasmodium life cycle; they are essential for the establishment of sporozoite infection in the mosquito salivary gland, and subsequently for development in hepatocytes. However, although Δpcrmp3 and Δpcrmp4 parasites are completely growth-impaired in the liver, immunization with live sporozoites does not induce the protective immune responses that have been shown for other genetically-attenuated parasites.

Caring for critically injured soldiers.

This article highlights the specific challenges faced by clinical staff caring for military casualties and identifies why routine clinical practice needs to be adapted to provide effective care. The types of injury are discussed as well as pain management regimens, which have to be tailored to accommodate particular patterns of injuries. Flashbacks and hallucinations are common problems following traumatic injury and affect each soldier differently. The need for psychological support is explored because this is one of the most challenging aspects of caring for military casualties and their families.

Real-time PCR assays for detection and quantification of early P. falciparum gametocyte stages.

The use of quantitative qRT-PCR assays for detection and quantification of late gametocyte stages has revealed the high transmission capacity of the human malaria parasite, Plasmodium falciparum. To understand how the parasite adjusts its transmission in response to in-host environmental conditions including antimalarials requires simultaneous quantification of early and late gametocytes. Here, we describe qRT-PCR assays that specifically detect and quantify early-stage P. falciparum gametocytes. The assays are based on expression of known early and late gametocyte genes and were developed using purified stage II and stage V gametocytes and tested in natural and controlled human infections. Genes pfpeg4 and pfg27 are specifically expressed at significant levels in early gametocytes with a limit of quantification of 190 and 390 gametocytes/mL, respectively. In infected volunteers, transcripts of pfpeg4 and pfg27 were detected shortly after the onset of blood stage infection. In natural infections, both early (pfpeg4/pfg27) and late gametocyte transcripts (pfs25) were detected in 71.2% of individuals, only early gametocyte transcripts in 12.6%, and only late gametocyte transcripts in 15.2%. The pfpeg4/pfg27 qRT-PCR assays are sensitive and specific for quantification of circulating sexually committed ring stages/early gametocytes and can be used to increase our understanding of epidemiological processes that modulate P. falciparum transmission.

Developing Medical Students' Broad Clinical Diagnostic Reasoning Through GP-Facilitated Teaching in Hospital Placements.

PURPOSE: Graduating medical students need broad clinical diagnostic reasoning skills that integrate learning across clinical specialties to deal with undifferentiated patient problems. The opportunity to acquire these skills may be limited during clinical placements on increasingly specialized hospital wards. We developed an intervention of regular general practitioner (GP) facilitated teaching in hospital placements to enable students to develop broad clinical diagnostic reasoning. The intervention was piloted, refined and delivered to a whole cohort of medical students at the start of their third year. This paper examines whether students perceived opportunities to improve their broad diagnostic clinical reasoning through our intervention. METHODS: GP-facilitated teaching sessions were delivered weekly in hospital placements to small groups of 6-8 students for 90 mins over 6 weeks. Students practiced clinical reasoning with real patient cases that they encountered on their placements. Evaluation of learning outcomes was conducted through a student questionnaire using Likert scales with free-text boxes for additional explanation. Focus groups were conducted to gain a more in-depth understanding of student perspectives. RESULTS: As high as 87% of students agreed that their broad clinical diagnostic reasoning ability had improved. Thematic analysis of the qualitative data revealed four factors supporting this improvement: practicing the hypothetico-deductive method, using real patient cases, composing student groups from different speciality placements and the breadth of the facilitators' knowledge. Students additionally reported enhanced person-centredness in terms of understanding the patient's perspective and journey. Students perceived that the added value of general practitioner facilitators lay in their broad knowledge base and knowledge of patient needs in the community. CONCLUSION: Our results suggest that medical students can develop broad clinical diagnostic reasoning skills in hospital settings through regular GP-facilitated teaching. Our approach has the advantage of working within the established curricular format of hospital placements and being deliverable at scale to whole student cohorts.

A Conserved TCRß Signature Dominates a Highly Polyclonal T-Cell Expansion During the Acute Phase of a Murine Malaria Infection.

CD4+ αß T-cells are key mediators of the immune response to a first Plasmodium infection, undergoing extensive activation and splenic expansion during the acute phase of an infection. However, the clonality and clonal composition of this expansion has not previously been described. Using a comparative infection model, we sequenced the splenic CD4+ T-cell receptor repertoires generated over the time-course of a Plasmodium chabaudi infection. We show through repeat replicate experiments, single-cell RNA-seq, and analyses of independent RNA-seq data, that following a first infection - within a highly polyclonal expansion - T-effector repertoires are consistently dominated by TRBV3 gene usage. Clustering by sequence similarity, we find the same dominant clonal signature is expanded across replicates in the acute phase of an infection, revealing a conserved pathogen-specific T-cell response that is consistently a hallmark of a first infection, but not expanded upon re-challenge. Determining the host or parasite factors driving this conserved response may uncover novel immune targets for malaria therapeutic purposes.