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Vaccines that target Plasmodium falciparum gametocytes have the potential to reduce malaria transmission and are thus attractive targets for malaria control. However, very little is known about human immune responses to gametocytes present in human hosts. We evaluated naturally-acquired antibodies to gametocyte-infected erythrocytes (gametocyte-IEs) of different developmental stages compared to other asexual parasite stages among naturally-exposed Kenyan residents. We found that acquired antibodies strongly recognized the surface of mature asexual-IEs, but there was limited reactivity to the surface of gametocyte-IEs of different stages. We used genetically-modified P. falciparum with suppressed expression of PfEMP1, the major surface antigen of asexual-stage IEs, to demonstrate that PfEMP1 is a dominant target of antibodies to asexual-IEs, in contrast to gametocyte-IEs. Antibody reactivity to gametocyte-IEs was similar to asexual-IEs lacking PfEMP1. Significant antibody reactivity to the surface of gametocytes was observed when outside of the host erythrocyte, including recognition of the major gametocyte antigen, Pfs230. This indicates that there is a deficiency of acquired antibodies to gametocyte-IEs despite the acquisition of antibodies to gametocyte antigens and asexual IEs. Our findings suggest that the acquisition of substantial immunity to the surface of gametocyte-IEs is limited, which may facilitate immune evasion to enable malaria transmission even in the face of substantial host immunity to malaria. Further studies are needed to understand the basis for the limited acquisition of antibodies to gametocytes and whether vaccine strategies can generate substantial immunity.

Although there has been major recent progress in malaria vaccine development, substantial challenges remain for achieving highly efficacious and durable vaccines against Plasmodium falciparum and Plasmodium vivax malaria. Greater knowledge of mechanisms and key targets of immunity are needed to accomplish this goal, together with new strategies for generating potent, long-lasting, functional immunity against multiple antigens. Implementation considerations in endemic areas will ultimately affect vaccine effectiveness, so innovations to simplify and enhance delivery are also needed. Whereas challenges remain, recent exciting progress and emerging knowledge promise hope for the future of malaria vaccines., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Background: Overcoming antigenic diversity is a key challenge in the development of effective Plasmodium falciparum malaria vaccines. Strategies that promote the generation of antibodies targeting conserved epitopes of vaccine antigens may provide protection against diverse parasites strains. Understanding differences between vaccine-induced and naturally acquired immunity is important to achieving this goal., Methods: We analyzed antibodies generated in a phase 1 human vaccine trial, MSP2-C1, which included 2 allelic forms of MSP2, an abundant vaccine antigen on the merozoite surface. Vaccine-induced responses were assessed for functional activity against multiple parasite strains, and cross-reactivity of antibodies was determined using competition ELISA and epitope mapping approaches., Results: Vaccination induced cytophilic antibody responses with strain-transcending opsonic phagocytosis and complement-fixing function. In contrast to antibodies acquired via natural infection, vaccine-induced antibodies were directed towards conserved epitopes at the C-terminus of MSP2, whereas naturally acquired antibodies mainly targeted polymorphic epitopes. Functional activity of C-terminal-targeted antibodies was confirmed using monoclonal antibodies that promoted opsonic phagocytosis against multiple parasite strains., Conclusion: Vaccination generated markedly different responses to polymorphic antigens than naturally acquired immunity and targeted conserved functional epitopes. Induction of antibodies targeting conserved regions of malaria antigens provides a promising vaccine strategy to overcome antigenic diversity for developing effective malaria vaccines.

Although preservation of high activity level has been reported in active young patients after periacetabular osteotomy (PAO) for the treatment of symptomatic hip dysplasia, there is limited evidence whether a dancer may be able to resume dancing after PAO. We asked whether female dancers experience improvement in pain and sports-related activities and return to dance following PAO. Between 1997 and 2014 we performed a total of 44 PAOs in 33 female dancers with symptomatic hip dysplasia. The mean age was 20.3 years (SD 5.6 years) and the median follow-up was 2.7 years (IQR 1.7-5.9 years). The Hip Disability and Osteoarthritis Outcome Score (HOOS), the modified Harris hip score (MHHS) and hip motion were collected preoperatively and at most recent follow-up. Return to dance was recorded from self-reported questionnaires and medical record review. Female dancers reported an improvement in HOOS total scores of nearly 20 points ( P  = 0.007) and MHHS improved over 17 points ( P  = 0.01) from preoperative to most-recent follow-up. Out of the 30 patients for whom information about return to dance was available, 19 (63%; 95% CI = 43.9-79.5%) had returned to dance at an average of 8.8 months (±3.6 months) after PAO. With the numbers available we did not identify any factors associated with returning to dance in this cohort. Improvement in hip pain, sports-related activities and hip function may be expected following PAO in young female dancers. Most female dancers can expect to return to dance during the first year after surgery.

Problem: Workplace violence, incidents against people in their workplaces, is a growing problem in Australia causing untold personal suffering as well as costing Australian businesses in productivity. Midwives have been highlighted as a group particularly at risk, yet in Australia there is little research into workplace violence against midwives and even less into midwifery students., Aim: This study aimed to explore Australian midwifery students' responses to workplace violence as well as to gauge the impact of workplace violence on them., Methods: Cross-sectional survey design was employed. Second and third year students were invited to participate at the end of a scheduled lecture. Fifty-two female midwifery students who had completed their work placement completed a survey indicating their immediate responses to workplace violence as well as the Impact of Event Scale. Data were analysed using descriptive statistics., Findings: Most students notified a co-worker immediately after a workplace violence incident, yet few completed an incident form or received official debriefing., Discussion: There is a need for the reporting of workplace violence against midwifery students to be made easier to access thereby ensuring they can receive the assistance they require. Midwifery students need to understand the processes and supports in place for managing instances of workplace violence., Conclusion: Clinical placements can impact on midwifery students' future careers. Universities need to prepare students for the possibility of workplace violence and arm them with appropriate strategies for safely dealing with it., (Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.)

Patients with developmental dysplasia of the hip (DDH) who undergo periacetabular osteotomy (PAO) often have labral tears. The objective of this retrospective study was to compare PAO alone with PAO combined with arthrotomy or arthroscopy in DDH patients who had a full-thickness labral tear on magnetic resonance imaging. In total, 47 hips in the PAO group (PAO) were compared with 60 hips in the PAO with concomitant arthrotomy or arthroscopy (PAO-A) with respect to Hip Disability and Osteoarthritis Outcome Score (HOOS), modified Harris Hip Score (mHHS), Visual Analog Scale (VAS), clinical and radiographic outcomes at a median of 29 months. Reoperation rate and complications were compared between two groups of treatment. The PAO group was younger than the PAO-A group (25.2 ± 9.7 versus 31.3 ± 8.3). The PAO group was more likely to have worse dysplasia: lateral center edge angle (7.6°±9.63° versus 10.8°±6.85°) and anterior center edge angle (4°±12.92° versus 10.8°±9.92°). The PAO group had a higher preoperative mHHS (65.2 ± 15.3 versus 57.8 ± 14.8) and HOOS (66.3 ± 17.5 versus 55.8 ± 20.1). There were no significant differences in final functional outcome scores across treatment groups: mHHS (PAO; 86.8 ± 12.4 versus PAO-A, 83.3 ± 17.2), HOOS (86.5 ± 13.3 versus 82.5 ± 16.8) and VAS (2.5 ± 2.8 versus 2.5 ± 3.1). There was no difference in reoperation rate between two groups (6.4% versus 11.6%, P  = 0.51). The overall complication rate was lower in the PAO group (26% versus 68%), but major complications were comparable. On the basis of our data, we were not able to conclusively demonstrate a clear benefit for the routine treatment of all labral tears; however, arthrotomy or arthroscopy may play a role in some conditions.

Background: The inability of paramedics to perform accurate calculations may result in a compromise of patient safety which may result from under or over dosing of drugs, incorrect joules for defibrillation, or a major adverse event such as death. The objective of this study was to identify the drug calculation and mathematical ability of qualified operational paramedics., Methods: The study used a cross-sectional design with a paper-based calculation questionnaire. Twenty paramedics enrolled in an intensive care paramedic course were eligible to participate in the study. The questionnaire consisted of demographic, drug calculation (seven questions), and mathematical (five) questions. Students were given no notice of the impending study and use of a calculator was not permitted., Results: All eligible students participated in the study. The average time employed as a paramedic was 7.25 years, SD 2.5 years, range four years to twelve years. Four (20%) students got all 12 questions correct, and five (41.6%) got 50% or less. The average score was 8.6 (71.7%) correct, SD 2.8 correct, range 3 to 12 correct questions. There were eight (40%) conceptual errors, 12 (60%) arithmetical errors, and five (25%) computational errors., Conclusion: The results from this study supports similar international studies where paramedic's ability to undertake mathematical and drug calculations without a calculator varies, with some results highlighting the paramedics mathematical skills as a potential risk to patient safety. These results highlight the need for regular continuing mathematical and drug calculation practice and education to ensure a lower error rate., Competing Interests: Conflicts of interest: The authors state they have no competing interests.

Despite recent successful control efforts, malaria remains a leading global health burden. Alarmingly, resistance to current antimalarials is increasing and the development of new drug families is needed to maintain malaria control. Current antimalarials target the intraerythrocytic developmental stage of the Plasmodium falciparum life cycle. However, the invasive extracellular parasite form, the merozoite, is also an attractive target for drug development. We have previously demonstrated that heparin-like molecules, including those with low molecular weights and low anticoagulant activities, are potent and specific inhibitors of merozoite invasion and blood-stage replication. Here we tested a large panel of heparin-like molecules and sulfated polysaccharides together with various modified chemical forms for their inhibitory activity against P. falciparum merozoite invasion. We identified chemical modifications that improve inhibitory activity and identified several additional sulfated polysaccharides with strong inhibitory activity. These studies have important implications for the further development of heparin-like molecules as antimalarial drugs and for understanding merozoite invasion., (Copyright © 2017 American Society for Microbiology.)

Cytokine-producing CD4 T cells have important roles in immunity against Plasmodium falciparum (Pf) malaria. However, the factors influencing functional differentiation of Pf- specific CD4 T cells in naturally exposed children are not well understood. Moreover, it is not known which CD4 T-cell cytokine-producing subsets are most critical for protection. We measured Pf- specific IFNγ-, IL10-, and TNFα-producing CD4 T-cell responses by multi-parametric flow cytometry in 265 children aged 6 months to 10 years enrolled in a longitudinal observational cohort in a high malaria transmission site in Uganda. We found that both age and parasite burden were independently associated with cytokine production by CD4 T cells. IL10 production by IFNγ + CD4 T cells was higher in younger children and in those with high-parasite burden during recent infection. To investigate the role of CD4 T cells in immunity to malaria, we measured associations of Pf -specific CD4 cytokine-producing cells with the prospective risk of Pf infection and clinical malaria, adjusting for household exposure to Pf -infected mosquitos. Overall, the prospective risk of infection was not associated with the total frequency of Pf- specific CD4 T cells, nor of any cytokine-producing CD4 subset. However, the frequency of CD4 cells producing IL10 but not inflammatory cytokines (IFNγ and TNFα) was associated with a decreased risk of clinical malaria once infected. These data suggest that functional polarization of the CD4 T-cell response may modulate the clinical manifestations of malaria and play a role in naturally acquired immunity.

Vδ2 + γδ T cells are semi-innate T cells that expand markedly following P. falciparum (Pf) infection in naïve adults, but are lost and become dysfunctional among children repeatedly exposed to malaria. The role of these cells in mediating clinical immunity (i.e. protection against symptoms) to malaria remains unclear. We measured Vδ2 + T cell absolute counts at acute and convalescent malaria timepoints (n = 43), and Vδ2 + counts, cellular phenotype, and cytokine production following in vitro stimulation at asymptomatic visits (n = 377), among children aged 6 months to 10 years living in Uganda. Increasing age was associated with diminished in vivo expansion following malaria, and lower Vδ2 absolute counts overall, among children living in a high transmission setting. Microscopic parasitemia and expression of the immunoregulatory markers Tim-3 and CD57 were associated with diminished Vδ2 + T cell pro-inflammatory cytokine production. Higher Vδ2 pro-inflammatory cytokine production was associated with protection from subsequent Pf infection, but also with an increased odds of symptoms once infected. Vδ2 + T cells may play a role in preventing malaria infection in children living in endemic settings; progressive loss and dysfunction of these cells may represent a disease tolerance mechanism that contributes to the development of clinical immunity to malaria.

Background: Complex proximal humeral fractures may require prosthetic replacement of the humeral head. Surgical options include reverse shoulder arthroplasty (RSA) and shoulder hemiarthroplasty; however, the optimal technique remains controversial. The goal of this study was to compare functional outcomes and revision rates of RSA with hemiarthroplasty in patients with acute proximal humeral fractures., Materials and Methods: Between January 1, 1999, and December 31, 2014, there were 218 patients who underwent RSA and 427 who underwent hemiarthroplasty for acute proximal humeral fractures identified through New Zealand Joint Registry records. Study groups were compared with regard to baseline characteristics, operative characteristics, and postoperative outcomes (Oxford Shoulder Score [OSS], revision rate, mortality rate) at 6 months and 5 years after surgery., Results: RSA patients were significantly older (mean age, 78.2 vs. 71.6 years; P < .001), with a higher proportion of female patients (90% vs. 77%; P < .001) than in the hemiarthroplasty group. No statistically significant difference existed in revision rate per 100 component-years (0.58 [RSA] vs. 1.16 [hemiarthroplasty]; P = .137) or 1-year mortality (3.8% vs. 3.4%; P = .805) between both groups. There was no significant difference in 6-month OSS (29.6 vs. 28.4; P = .305). The RSA group demonstrated a superior mean 5-year OSS (37.6 vs. 32.7; P = .078); however, the difference did not achieve statistical significance., Conclusions: Although our results suggest that RSA patients may experience superior 5-year functional scores, we have identified no significant difference in functional outcomes and revision rates between RSA and hemiarthroplasty in the treatment of acute proximal humeral fractures., (Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Natural selection that affected modern humans early in their evolution has likely shaped some of the traits that set present-day humans apart from their closest extinct and living relatives. The ability to detect ancient natural selection in the human genome could provide insights into the molecular basis for these human-specific traits. Here, we introduce a method for detecting ancient selective sweeps by scanning for extended genomic regions where our closest extinct relatives, Neandertals and Denisovans, fall outside of the present-day human variation. Regions that are unusually long indicate the presence of lineages that reached fixation in the human population faster than expected under neutral evolution. Using simulations, we show that the method is able to detect ancient events of positive selection and that it can differentiate those from background selection. Applying our method to the 1000 Genomes data set, we find evidence for ancient selective sweeps favoring regulatory changes and present a list of genomic regions that are predicted to underlie positively selected human specific traits., (© 2017 Peyrégne et al.; Published by Cold Spring Harbor Laboratory Press.)

Clinical responses to infection or vaccination and the development of effective immunity are characterized in humans by a marked interindividual variability. To gain an insight into the factors affecting this variability, we used a controlled human infection system to study early immune events following primary infection of healthy human volunteers with blood-stage Plasmodium falciparum malaria. By day 4 of infection, a dichotomous pattern of high or low expression of a defined set of microRNAs (miRs) emerged in volunteers that correlated with variation in parasite growth rate. Moreover, high-miR responders had higher numbers of activated CD4+ T cells, and developed significantly enhanced antimalarial antibody responses. Notably, a set of 17 miRs was identified in the whole blood of low-miR responders prior to infection that differentiated them from high-miR responders. These data implicate preexisting host factors as major determinants in the ability to effectively respond to primary malaria infection.

Background: In populations pauci-immune to malaria, risk of severe malaria increases with age. This is particularly apparent in Plasmodium knowlesi malaria. However, pathophysiological mechanisms underlying knowlesi malaria, and of the age-related increase in risk of severe malaria in general, are poorly understood., Methods: In Malaysian patients aged ≥12 years with severe (n = 47) and nonsevere (n = 99) knowlesi malaria, severe (n = 21) and nonsevere (n = 109) falciparum malaria, and healthy controls (n = 50), we measured parasite biomass, systemic inflammation (interleukin 6 [IL-6]), endothelial activation (angiopoietin-2), and microvascular function, and evaluated the effects of age., Results: Plasmodium knowlesi parasitemia correlated with age (Spearman's correlation coefficient [rs] = 0.36; P < .0001). In knowlesi malaria, IL-6, angiopoietin-2, and microvascular dysfunction were increased in severe compared to nonsevere disease, and all correlated with age, independent of parasitemia. In falciparum malaria, angiopoietin-2 increased with age, independent of parasite biomass (histidine-rich protein 2 [HRP2]). Independent risk factors for severe malaria included parasitemia and angiopoietin-2 in knowlesi malaria, and HRP2, angiopoietin-2, and microvascular dysfunction in falciparum malaria., Conclusions: Parasite biomass, endothelial activation, and microvascular dysfunction are associated with severe disease in knowlesi malaria and likely contribute to pathogenesis. The association of each of these processes with aging may account for the greater severity of malaria observed in older adults in low-endemic regions., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Femoral neck stress fractures are rare in healthy children, with only 9 cases previously reported. The present article reviews our institutional experience with femoral neck stress fractures in children younger than 10 years of age, to highlight the unique features of this condition., Methods: We undertook a retrospective review of clinical records of patients who had been treated at our institution for an idiopathic femoral neck stress fracture between 2000 and 2014. To focus on children rather than adolescents, the World Health Organization's definition of adolescent as a person between 10 and 19 years of age was used; we thereby limited our analysis to patients younger than 10 years of age., Results: The study included 6 patients (3 males, 3 females) treated for an idiopathic femoral neck stress fracture, with a mean age at diagnosis of 7.7 years (range, 5.2 to 8.9 y). All patients presented with a limp, which worsened with activity and had persisted for a mean of 5 weeks (range, 2 to 9 wk). None of the patients had experienced an increase in activity level or sporting volume before symptom onset. On examination, 3 patients experienced pain with terminal hip flexion and 3 patients demonstrated pain-free hip range of motion. Plain radiography demonstrated inferior femoral neck cortical disruption, suggesting a compression-type stress fracture mechanism. The diagnosis was confirmed by cross-sectional imaging in all cases. All patients were initially treated with 6 to 8 weeks of non-weight-bearing followed by 4 to 6 weeks of partial weight-bearing, leading to complete healing in 4 patients. Two patients demonstrated incomplete healing and were managed with spica casting for an additional 6 weeks., Conclusions: Our case series illustrates the unique features of this rare condition in children, with a history and examination profile distinct from those of adolescents and adults. Compliance with weight-bearing restrictions is difficult in this population and hip spica casting may be required to permit complete healing., Level of Evidence: Level IV-case series.

Recent efforts in malaria control have led to marked reductions in malaria incidence. However, new strategies are needed to sustain malaria elimination and eradication and achieve the World Health Organization goal of a malaria-free world. The development of highly effective vaccines would contribute to this goal and would be facilitated by a comprehensive understanding of humoral immune responses targeting Plasmodium falciparum and Plasmodium vivax malaria. New tools are required to facilitate the identification of vaccine candidates and the development of vaccines that induce functional and protective immunity. Here we discuss recent published findings, and unpublished work presented at the 2016 Molecular Approaches to Malaria conference, that highlight advancements in understanding humoral immune responses in the context of vaccine development. Highlights include the increased application of 'omics' and 'Big data' platforms to identify vaccine candidates, and the identification of novel functions of antibody responses that mediate protection. The application of these strategies and a global approach will increase the likelihood of rapid development of highly efficacious vaccines., (Copyright © 2016 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.)

Background: Plasmodium falciparum malaria remains a leading cause of childhood morbidity and mortality. There are important gaps in our understanding of the factors driving the development of antimalaria immunity as a function of age and exposure., Methods: We used data from a cohort of 93 children participating in a clinical trial in Tororo, Uganda, an area of very high exposure to P. falciparum We jointly quantified individual heterogeneity in the risk of infection and the development of immunity against infection and clinical disease., Results: Results showed significant heterogeneity in the hazard of infection and independent effects of age and cumulative number of infections on the risk of infection and disease. The risk of developing clinical malaria upon infection decreased on average by 6% (95% confidence interval [CI], 0%-12%) for each additional year of age and by 2% (95% CI, 1%-3%) for each additional prior infection. Children randomly assigned to receive dihydroartemisinin-piperaquine for treatment appeared to develop immunity more slowly than those receiving artemether-lumefantrine., Conclusions: Heterogeneity in P. falciparum exposure and immunity can be independently evaluated using detailed longitudinal studies. Improved understanding of the factors driving immunity will provide key information to anticipate the impact of malaria-control interventions and to understand the mechanisms of clinical immunity., (© The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.)

Background: Polydactyly of the foot is a relatively common condition. Approximately 15% of cases are preaxial, with one third of these cases involving duplication of the metatarsal [metatarsal type preaxial polydactyly (MTPP)].Surgical reconstruction of polydactyly is indicated to improve shoe tolerance. Reconstruction of MTPP has traditionally involved resection of the hypoplastic lateral ray in addition to soft tissue reconstruction to correct hallux varus. Poor postoperative results have frequently been reported, primarily due to residual hallux varus. We present a novel surgical technique for the treatment of children with MTPP presenting with a cosmetic lateral hallux, involving an amalgamating osteotomy that permits retention of the stable medial metatarsotarsal joint while avoiding the complication of residual hallux varus., Methods: This was a retrospective case series describing the surgical technique of an amalgamating osteotomy in the treatment of patients with MTPP and a cosmetic lateral hallux. The surgical technique involves corresponding metatarsal osteotomies of the medial and lateral halluces, with amalgamation of the metatarsals and ablation of the residual medial hallux, without the need for extensive soft tissue reconstruction. Clinical and radiologic outcomes were evaluated at a minimum of 2 years postoperatively in 2 patients who underwent this technique., Results: Two children, 1 female and 1 male, underwent an amalgamating osteotomy at the age of 31 and 18 months, respectively. At latest follow-up, 7.3 and 2.8 years after osteotomy, respectively, both patients displayed an excellent functional result according to the Phelps and Grogan clinical outcome scale. Plain radiographs in both cases demonstrated a well-aligned first ray with no growth abnormality and no hallux varus., Conclusions: We have presented a novel surgical technique for the reconstruction of MTPP presenting with a cosmetic lateral hallux, involving an amalgamating osteotomy without extensive soft tissue reconstruction. This simple technique maintains the stable medial metatarsotarsal joint, permits ongoing longitudinal metatarsal growth, and avoids the complication of hallux varus., Level of Evidence: Level IV-case series.

In humans, immunity to Plasmodium sp. generally takes the form of protection from symptomatic malaria (i.e., 'clinical immunity') rather than infection ('sterilizing immunity'). In contrast, mice infected with Plasmodium develop sterilizing immunity, hindering progress in understanding the mechanistic basis of clinical immunity. Here we present a novel model in which mice persistently infected with P. chabaudi exhibit limited clinical symptoms despite sustaining patent parasite burdens for many months. Characterization of immune responses in persistently infected mice revealed development of CD4+ T cell exhaustion, increased production of IL-10, and expansion of B cells with an atypical surface phenotype. Additionally, persistently infected mice displayed a dramatic increase in circulating nonclassical monocytes, a phenomenon that we also observed in humans with both chronic Plasmodium exposure and asymptomatic infection. Following pharmacological clearance of infection, previously persistently infected mice could not control a secondary challenge, indicating that persistent infection disrupts the sterilizing immunity that typically develops in mouse models of acute infection. This study establishes an animal model of asymptomatic, persistent Plasmodium infection that recapitulates several central aspects of the immune response in chronically exposed humans. As such, it provides a novel tool for dissection of immune responses that may prevent development of sterilizing immunity and limit pathology during infection., Competing Interests: LB is an employee of EPIRUS Biopharmaceuticals. This commercial affiliation does not alter our adherence to PLOS ONE policies on sharing data and materials.

Background: Experimental inoculation of viable Plasmodium falciparum sporozoites administered with chemoprevention targeting blood-stage parasites results in protective immunity. It is unclear whether chemoprevention similarly enhances immunity following natural exposure to malaria., Methods: We assessed P. falciparum-specific T-cell responses among Ugandan children who were randomly assigned to receive monthly dihydroartemisinin-piperaquine (DP; n = 87) or no chemoprevention (n = 90) from 6 to 24 months of age, with pharmacologic assessments for adherence, and then clinically followed for an additional year., Results: During the intervention, monthly DP reduced malaria episodes by 55% overall (P < .001) and by 97% among children who were highly adherent to DP (P < .001). In the year after the cessation of chemoprevention, children who were highly adherent to DP had a 55% reduction in malaria incidence as compared to children given no chemoprevention (P = .004). Children randomly assigned to receive DP had higher frequencies of blood-stage specific CD4(+) T cells coproducing interleukin-2 and tumor necrosis factor α (P = .003), which were associated with protection from subsequent clinical malaria and parasitemia, and fewer blood-stage specific CD4(+) T cells coproducing interleukin-10 and interferon γ (P = .001), which were associated with increased risk of malaria., Conclusions: In this setting, effective antimalarial chemoprevention fostered the development of CD4(+) T cells that coproduced interleukin 2 and tumor necrosis factor α and were associated with prospective protection, while limiting CD4(+) T-cell production of the immunoregulatory cytokine IL-10., (© The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.)

Purpose: Contralateral hip involvement in slipped capital femoral epiphysis (SCFE) is common. Femoral head-neck asphericity, as measured by an elevated alpha angle, has not previously been assessed with respect to SCFE risk. Our aim was to assess the utility of the alpha angle in predicting contralateral SCFE., Methods: We retrospectively reviewed 168 patients (94 males) managed surgically for unilateral SCFE between 2001 and 2013 who had a minimum of 18 months follow-up. The alpha angle, the posterior sloping angle (PSA), and the modified Oxford score were recorded for every patient at the time of initial SCFE presentation. Follow-up clinical records and radiographs were assessed to determine the presence of absence of contralateral SCFE., Results: Forty-five patients (27 %) developed a contralateral SCFE. Patients who developed a contralateral SCFE had a significantly higher alpha angle (51° vs 45°, p < 0.001) than patients who did not develop a contralateral SCFE. There was no significant difference in PSA or modified Oxford score (both p > 0.10) between patients who developed a contralateral SCFE and those who did not. Using a proposed alpha angle of 50.5° as a threshold for prophylactic fixation, 26 (58 %) of the 45 cases of contralateral SCFE in our study would have been prevented and 18 (15 %) of 123 patients would have undergone fixation unnecessarily., Conclusions: We found the alpha angle to positively correlate with contralateral SCFE risk. Patients with significantly elevated alpha angles may be at greater risk of contralateral SCFE and benefit from further investigation or prophylactic hip fixation.

Objective: Detail the imaging findings in patients with proximal tibiofibular instability treated with surgical stabilization., Methods: Retrospective analysis of preoperative imaging in patients with clinically confirmed tibiofibular instability., Results: Operative fixation of the 16 patients was as follows: 11 using a fiberwire suture construct and 5 using screw fixation. Proximal tibiofibular ligamentous abnormalities were present in 100% of acute (< 6 months) and 85.7% of chronic (>6 months) instability cases who underwent MRI., Conclusion: MRI is sensitive in the evaluation of tibiofibular ligamentous integrity in proximal tibiofibular instability. Chronic instability should be considered in younger adults with isolated tibiofibular osteoarthritis., (Copyright © 2016 Elsevier Inc. All rights reserved.)

γδ T cells expressing Vδ2 may be instrumental in the control of malaria, because they inhibit the replication of blood-stage parasites in vitro and expand during acute malaria infection. However, Vδ2 T-cell frequencies and function are lower among children with heavy prior malaria exposure. It remains unclear whether malaria itself is driving this loss. Here we measure Vδ2 T-cell frequency, cytokine production, and degranulation longitudinally in Ugandan children enrolled in a malaria chemoprevention trial from 6 to 36 months of age. We observed a progressive attenuation of the Vδ2 response only among children incurring high rates of malaria. Unresponsive Vδ2 T cells were marked by expression of CD16, which was elevated in the setting of high malaria transmission. Moreover, chemoprevention during early childhood prevented the development of dysfunctional Vδ2 T cells. These observations provide insight into the role of Vδ2 T cells in the immune response to chronic malaria., (© The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.)

Malaria accounts for an enormous burden of disease globally, with Plasmodium falciparum accounting for the majority of malaria, and P. vivax being a second important cause, especially in Asia, the Americas and the Pacific. During infection with Plasmodium spp., the merozoite form of the parasite invades red blood cells and replicates inside them. It is during the blood-stage of infection that malaria disease occurs and, therefore, understanding merozoite invasion, host immune responses to merozoite surface antigens, and targeting merozoite surface proteins and invasion ligands by novel vaccines and therapeutics have been important areas of research. Merozoite invasion involves multiple interactions and events, and substantial processing of merozoite surface proteins occurs before, during and after invasion. The merozoite surface is highly complex, presenting a multitude of antigens to the immune system. This complexity has proved challenging to our efforts to understand merozoite invasion and malaria immunity, and to developing merozoite antigens as malaria vaccines. In recent years, there has been major progress in this field, and several merozoite surface proteins show strong potential as malaria vaccines. Our current knowledge on this topic is reviewed, highlighting recent advances and research priorities., (© FEMS 2016.)

Background: Adolescent patients undergoing anterior cruciate ligament (ACL) reconstruction may not adequately recover safe movement patterns before returning to sport participation. The aims of this study were to assess functional movement and dynamic balance 9 months after primary ACL reconstruction in adolescent patients, and to assess for any maturity-specific differences that may guide rehabilitation strategies., Methods: A series of 39 adolescent patients who underwent primary, anatomic, transphyseal ACL reconstruction using hamstrings autograft from October 2009 to January 2013 were identified from a research database: 17 skeletally immature (SI) patients (mean age 13.6±1.6 y) and 22 skeletally mature (SM) patients (mean age 16.6±1.2 y). An adult reference population of 16 primary ACL reconstruction patients (mean age 27.4±4.0 y) was also identified. All patients followed a standardized operative and rehabilitation protocol. The 3 patient groups were compared 9 months postoperatively using the Functional Movement Screen (FMS) to assess movement competency and the Lower Quarter Y-Balance Test (LQYBT) to assess single-limb dynamic balance., Results: Nine months postoperatively, the FMS scores for all 3 groups indicated an increased risk for lower extremity injury (total score ≤14). With respect to specific movement patterns, the SI group displayed inferior active straight leg raise score (P=0.006) despite a lower incidence of pain with this movement. With the LQYBT, there was no significant difference in mean anterior (P=0.987), posterolateral (P=0.349), or posteromedial (P=0.870) reach asymmetry between the 3 groups; however, the adolescent groups demonstrated wider ranges of anterior reach asymmetry than the adult group indicating an increased risk for injury., Conclusions: Adolescent patients undergoing primary ACL reconstruction do not consistently recover adequate functional movement patterns by 9 months postoperatively to permit a safe return to sport. We have identified unique functional movement deficits in SI and SM adolescents, which highlight the need for maturity-specific rehabilitation strategies for adolescent patients undergoing ACL reconstruction., Level of Evidence: Level IV—retrospective cohort

One of the cornerstones in resuscitation training is defibrillation safety, inadvertent "shocking" of the patient when another person has contact with the patient may have a range of safety consequences. The objective of the study was to assess visual and verbal safety checks by paramedic students prior to defibrillation. This was a prospective observational mannequin study of defibrillation safety during a simulated cardiac arrest by paramedic students. The study was conducted in the lounge room of the Department of Community Emergency Health & Paramedic Practice simulation flat, a replica of a complete flat where prehospital simulations are conducted. Each student completed two 10-min cardiac arrest simulations with multiple defibrillation attempts. Each student and an independent Faculty member rated the simulation safety performance using a defibrillation safety self-assessment (DSSA) form. Twenty-four (20 %) students participated in the study with 14 (58 %) being female. For scenario one agreement between student and assessor proved significant for "scanning the incident scene" for all three defibrillation attempts, with agreement ranging from 29 % (p = 0.044) to 47 % (p = 0.007), and stating "stand clear" for defibrillation attempt one and three with the agreement ranging from 47 % (p = 0.007) to 100 % (p < 0.001). For scenario two agreement between student and assessor proved significant for "charging eye contact" for all three defibrillation attempts, with agreement ranging from 40 % (p = 0.043) to 53 % (p = 0.003), and "scanning the scene to ensure all persons are clear of the patient" before defibrillation attempt one and two with agreement ranging from 29 % (p = 0.044) to 46 % (p < 0.007). The results of this study suggest student perception of their performance and what they actually do is vastly different. Further studies using video recording glasses are required so students can gain an accurate and realistic sense of their defibrillation safety performance.

Background: Recent biomechanical research has suggested that adjustable-loop graft suspension constructs in anterior cruciate ligament (ACL) reconstruction may loosen after deployment. Our objective was to compare short-term knee stability and graft failure rate between adjustable-loop and fixed-loop femoral cortical suspension in patients undergoing primary ACL reconstruction., Methods: A consecutive series of 188 patients who underwent primary ACL reconstruction using hamstrings autograft by a single surgeon were divided into two groups; 73 received adjustable-loop (TightRope RT (Arthrex Inc., Naples, FL)) and 115 received fixed-loop (RetroButton (Arthrex Inc., Naples, FL)) femoral cortical suspension. The two groups were compared at six months, one year, and two years postoperatively using KT-1000 arthrometer testing and graft failure rate (revision surgery, grade 2+ Lachman test, any pivot shift, >5mm side-to-side KT-1000 difference)., Results: There was no significant difference between the two groups in maximum side-to-side difference in KT-1000 testing at six months (mean 1.51mm (adjustable-loop group) vs. 1.79mm (fixed-loop group), p=0.23), one year (mean 1.44mm vs. 1.64mm, p=0.48), or two years (mean 1.14mm vs. 1.07mm, p=0.90) postoperatively. There was no significant difference between the two groups in rate of graft failure (10% vs. 11%, p=0.71) or timing of graft failure in affected patients (mean 11.4months vs. 13.8months, p=0.51)., Conclusions: We found no significant difference in postoperative knee stability or graft failure rate between adjustable-loop and fixed-loop femoral cortical suspension in patients undergoing primary ACL reconstruction. Our results suggest that adjustable-loop suspension does not clinically loosen after ACL reconstruction., Level of Evidence: III (retrospective cohort study)., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Mechanisms mediating immunity to malaria remain unclear, but animal data and experimental human vaccination models suggest a critical role for CD4(+) T cells. Advances in multiparametric flow cytometry have revealed that the functional quality of pathogen-specific CD4(+) T cells determines immune protection in many infectious models. Little is known about the functional characteristics of Plasmodium-specific CD4(+) T-cell responses in immune and nonimmune individuals., Methods: We compared T-cell responses to Plasmodium falciparum among household-matched children and adults residing in settings of high or low malaria transmission in Uganda. Peripheral blood mononuclear cells were stimulated with P. falciparum antigen, and interferon γ (IFN-γ), interleukin 2, interleukin 10, and tumor necrosis factor α (TNF-α) production was analyzed via multiparametric flow cytometry., Results: We found that the magnitude of the CD4(+) T-cell responses was greater in areas of high transmission but similar between children and adults in each setting type. In the high-transmission setting, most P. falciparum-specific CD4(+) T-cells in children produced interleukin 10, while responses in adults were dominated by IFN-γ and TNF-α. In contrast, in the low-transmission setting, responses in both children and adults were dominated by IFN-γ and TNF-α., Conclusions: These findings highlight major differences in the CD4(+) T-cell response of immune adults and nonimmune children that may be relevant for immune protection from malaria., (© The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

FoxP3+ regulatory CD4 T cells (Tregs) help to maintain the delicate balance between pathogen-specific immunity and immune-mediated pathology. Prior studies suggest that Tregs are induced by P. falciparum both in vivo and in vitro; however, the factors influencing Treg homeostasis during acute and chronic infections, and their role in malaria immunopathogenesis, remain unclear. We assessed the frequency and phenotype of Tregs in well-characterized cohorts of children residing in a region of high malaria endemicity in Uganda. We found that both the frequency and absolute numbers of FoxP3+ Tregs in peripheral blood declined markedly with increasing prior malaria incidence. Longitudinal measurements confirmed that this decline occurred only among highly malaria-exposed children. The decline of Tregs from peripheral blood was accompanied by reduced in vitro induction of Tregs by parasite antigen and decreased expression of TNFR2 on Tregs among children who had intense prior exposure to malaria. While Treg frequencies were not associated with protection from malaria, there was a trend toward reduced risk of symptomatic malaria once infected with P. falciparum among children with lower Treg frequencies. These data demonstrate that chronic malaria exposure results in altered Treg homeostasis, which may impact the development of antimalarial immunity in naturally exposed populations.

Exposure to Plasmodium falciparum is associated with circulating "atypical" memory B cells (atMBCs), which appear similar to dysfunctional B cells found in HIV-infected individuals. Functional analysis of atMBCs has been limited, with one report suggesting these cells are not dysfunctional but produce protective antibodies. To better understand the function of malaria-associated atMBCs, we performed global transcriptome analysis of these cells, obtained from individuals living in an area of high malaria endemicity in Uganda. Comparison of gene expression data suggested down-modulation of B cell receptor signaling and apoptosis in atMBCs compared to classical MBCs. Additionally, in contrast to previous reports, we found upregulation of Fc receptor-like 5 (FCRL5), but not FCRL4, on atMBCs. Atypical MBCs were poor spontaneous producers of antibody ex vivo, and higher surface expression of FCRL5 defined a distinct subset of atMBCs compromised in its ability to produce antibody upon stimulation. Moreover, higher levels of P. falciparum exposure were associated with increased frequencies of FCRL5+ atMBCs. Together, our findings suggest that FCLR5+ identifies a functionally distinct, and perhaps dysfunctional, subset of MBCs in individuals exposed to P. falciparum.

Invertebrates are dominant species in primary tropical rainforests, where their abundance and diversity contributes to the functioning and resilience of these globally important ecosystems. However, more than one-third of tropical forests have been logged, with dramatic impacts on rainforest biodiversity that may disrupt key ecosystem processes. We find that the contribution of invertebrates to three ecosystem processes operating at three trophic levels (litter decomposition, seed predation and removal, and invertebrate predation) is reduced by up to one-half following logging. These changes are associated with decreased abundance of key functional groups of termites, ants, beetles and earthworms, and an increase in the abundance of small mammals, amphibians and insectivorous birds in logged relative to primary forest. Our results suggest that ecosystem processes themselves have considerable resilience to logging, but the consistent decline of invertebrate functional importance is indicative of a human-induced shift in how these ecological processes operate in tropical rainforests.

Introduction: Joint pain and raised inflammatory markers are features of both acute rheumatic fever (ARF) and septic arthritis, often posing a diagnostic challenge to clinicians. Important differences in the presenting serological inflammatory marker profile may assist patient diagnosis, however, as clinical experience suggests that ARF is associated with a higher erythrocyte sedimentation rate (ESR), whereas other serological markers may be similarly elevated in these 2 conditions., Objective: The goal of this study was to determine the diagnostic value of serological inflammatory markers and white cell count (WCC) in children presenting with acute joint pain secondary to ARF or septic arthritis., Methods: Data were obtained from the Auckland regional rheumatic fever database and hospital computer records between 2005 and 2012. Records of all patients under the age of 16 years who were admitted with a new diagnosis of ARF or septic arthritis were analyzed. The diagnosis of ARF was defined on the basis of the New Zealand modification of the Jones Criteria, and the diagnosis of septic arthritis was defined on the basis of joint fluid cytology and culture. Baseline characteristics, serological inflammatory markers, and serum WCC were compared between the ARF and septic arthritis patient groups., Results: Children with ARF displayed significantly higher ESR, higher serum C-reactive protein, and lower serum WCC than children with septic arthritis on presentation to hospital. In children presenting with monoarthritis, an ESR>64.5, serum WCC<12.1×109/L, and age above 8.5 years were found to be significant independent predictors of ARF. Children with all 3 predictors had a 71% risk for ARF and a 29% risk for septic arthritis. A significant proportion (30%) of children with the final diagnosis of ARF initially presented with monoarthritis; 14% of these children (5/34) had received nonsteroidal anti-inflammatory medication before hospital presentation, and 74% of these children (25/34) had abnormal echocardiograms on admission., Conclusions: ARF and septic arthritis are important diagnoses to consider in children presenting with acute joint pain in New Zealand. A significant proportion of patients with ARF initially present with acute monoarthritis. Serological inflammatory markers and WCC on presentation differ significantly between children with ARF and septic arthritis.

Antibodies play major roles in immunity to malaria; however, a limited understanding of mechanisms mediating protection is a major barrier to vaccine development. We have demonstrated that acquired human anti-malarial antibodies promote complement deposition on the merozoite to mediate inhibition of erythrocyte invasion through C1q fixation and activation of the classical complement pathway. Antibody-mediated complement-dependent (Ab-C') inhibition was the predominant invasion-inhibitory activity of human antibodies; most antibodies were non-inhibitory without complement. Inhibitory activity was mediated predominately via C1q fixation, and merozoite surface proteins 1 and 2 were identified as major targets. Complement fixation by antibodies was very strongly associated with protection from both clinical malaria and high-density parasitemia in a prospective longitudinal study of children. Ab-C' inhibitory activity could be induced by human immunization with a candidate merozoite surface-protein vaccine. Our findings demonstrate that human anti-malarial antibodies have evolved to function by fixing complement for potent invasion-inhibitory activity and protective immunity., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Sipunculans (also known as peanut worms) are an ancient group of exclusively marine worms with a global distribution and a fossil record that dates back to the Early Cambrian. The systematics of sipunculans, now considered a distinct subclade of Annelida, has been studied for decades using morphological and molecular characters, and has reached the limits of Sanger-based approaches. Here, we reevaluate their family-level phylogeny by comparative transcriptomic analysis of eight species representing all known families within Sipuncula. Two data matrices with alternative gene occupancy levels (large matrix with 675 genes and 62% missing data; reduced matrix with 141 genes and 23% missing data) were analysed using concatenation and gene-tree methods, yielding congruent results and resolving each internal node with maximum support. We thus corroborate prior phylogenetic work based on molecular data, resolve outstanding issues with respect to the familial relationships of Aspidosiphonidae, Antillesomatidae and Phascolosomatidae, and highlight the next area of focus for sipunculan systematics., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Our aim was to compare the one-year post-operative outcomes following retention or removal of syndesmotic screws in adult patients with a fracture of the ankle that was treated surgically. A total of 51 patients (35 males, 16 females), with a mean age of 33.5 years (16 to 62), undergoing fibular osteosynthesis and syndesmotic screw fixation, were randomly allocated to retention of the syndesmotic screw or removal at three months post-operatively. The two groups were comparable at baseline. One year post-operatively, there was no significant difference in the mean Olerud-Molander ankle score (82.4 retention vs 86.7 removal, p = 0.367), the mean American Orthopedic Foot and Ankle Society ankle-hindfoot score (88.6 vs 90.1, p = 0.688), the mean American Academy of Orthopedic Surgeons foot and ankle score (96.3 vs 94.0, p = 0.250), the mean visual analogue pain score (1.0 vs 0.7, p = 0.237), the mean active dorsiflexion (10.2° vs 13.0°, p = 0.194) and plantar flexion (33.6° vs 31.3°, p = 0.503) of the ankle, or the mean radiological tibiofibular clear space (5.0 mm vs 5.3 mm, p = 0.276) between the two groups. A total of 19 patients (76%) in the retention group had a loose and/or broken screw one year post-operatively. We conclude that removal of a syndesmotic screw produces no significant functional, clinical or radiological benefit in adult patients who are treated surgically for a fracture of the ankle., (©2014 The British Editorial Society of Bone & Joint Surgery.)

Background: Midterm outcomes after arthroscopic debridement in patients with anterior ankle impingement without osteoarthritis are currently unclear., Purpose: To assess the functional and radiological outcomes after arthroscopic treatment of anterior ankle impingement with a minimum 5-year follow-up in patients without osteoarthritis., Study Design: Case series; Level of evidence, 4., Methods: From September 1999 to March 2006, a consecutive series of eligible patients without ankle osteoarthritis and with anterior ankle impingement, who had persistent ankle pain and activity restrictions despite at least 6 months of nonoperative management, underwent standardized arthroscopic debridement and followed uniform postoperative management. Patients were assessed preoperatively and at 6 weeks, 6 months, and 12 months and then at 1-year intervals after surgery until a minimum of 5 years' follow-up had been achieved, with weightbearing ankle dorsiflexion, Foot Functional Index (FFI), and plain radiography including Scranton and McDermott classification (SMC) grade and tibial osteophyte size., Results: A total of 46 patients (42 male, 4 female) were prospectively assessed, with a mean age at surgery of 29 years (range, 16-44 years) and a mean follow-up duration of 5.1 years (range, 5.0-7.5 years). Preoperative ankle radiographs demonstrated a median SMC grade of 2 and a mean tibial osteophyte size of 5.1 mm. At a minimum of 5 years postoperatively, patients demonstrated limited improvement in ankle dorsiflexion (mean, 24.7° [preoperatively] vs 27.0° [final follow-up]; P = .049); however, they demonstrated substantial improvement in the FFI (mean, 20.5 [preoperatively] vs 2.7 [final follow-up]; P < .001). Postoperatively, 84% of patients showed a recurrence of radiological osteophytes, with plain radiographs at final follow-up demonstrating no significant difference in the SMC grade (P = .107) or tibial osteophyte size (P = .212) compared with preoperative imaging. There was no significant effect of patient age, sex, body mass index, or SMC grade at the time of surgery on any of the postoperative outcome measures., Conclusion: In this prospective outcome study of 46 patients without osteoarthritis managed arthroscopically for anterior ankle impingement, the functional outcome scores had significantly improved at 5 years postoperatively despite a recurrence of radiographic osteophytes., (© 2014 The Author(s).)

Background: Metazoan digestive systems develop from derivatives of ectoderm, endoderm and mesoderm, and vary in the relative contribution of each germ layer across taxa and between gut regions. In a small number of well-studied model systems, gene regulatory networks specify endoderm and mesoderm of the gut within a bipotential germ layer precursor, the endomesoderm. Few studies have examined expression of endomesoderm genes outside of those models, and thus, it is unknown whether molecular specification of gut formation is broadly conserved. In this study, we utilize a sequenced genome and comprehensive fate map to correlate the expression patterns of six transcription factors with embryonic germ layers and gut subregions during early development in Capitella teleta., Results: The genome of C. teleta contains the five core genes of the sea urchin endomesoderm specification network. Here, we extend a previous study and characterize expression patterns of three network orthologs and three additional genes by in situ hybridization during cleavage and gastrulation stages and during formation of distinct gut subregions. In cleavage stage embryos, Ct-otx, Ct-blimp1, Ct-bra and Ct-nkx2.1a are expressed in all four macromeres, the endoderm precursors. Ct-otx, Ct-blimp1, and Ct-nkx2.1a are also expressed in presumptive endoderm of gastrulae and later during midgut development. Additional gut-specific expression patterns include Ct-otx, Ct-bra, Ct-foxAB and Ct-gsc in oral ectoderm; Ct-otx, Ct-blimp1, Ct-bra and Ct-nkx2.1a in the foregut; and both Ct-bra and Ct-nkx2.1a in the hindgut., Conclusions: Identification of core sea urchin endomesoderm genes in C. teleta indicates they are present in all three bilaterian superclades. Expression of Ct-otx, Ct-blimp1 and Ct-bra, combined with previously published Ct-foxA and Ct-gataB1 patterns, provide the most comprehensive comparison of these five orthologs from a single species within Spiralia. Each ortholog is likely involved in endoderm specification and midgut development, and several may be essential for establishment of the oral ectoderm, foregut and hindgut, including specification of ectodermal and mesodermal contributions. When the five core genes are compared across the Metazoa, their conserved expression patterns suggest that 'gut gene' networks evolved to specify distinct digestive system subregions, regardless of species-specific differences in gut architecture or germ layer contributions within each subregion.

Background: An understanding of the mechanisms mediating protective immunity against malaria in humans is currently lacking, but critically important to advance the development of highly efficacious vaccines. Antibodies play a key role in acquired immunity, but the functional basis for their protective effect remains unclear. Furthermore, there is a strong need for immune correlates of protection against malaria to guide vaccine development., Methods: Using a validated assay to measure opsonic phagocytosis of Plasmodium falciparum merozoites, we investigated the potential role of this functional activity in human immunity against clinical episodes of malaria in two independent cohorts (n = 109 and n = 287) experiencing differing levels of malaria transmission and evaluated its potential as a correlate of protection., Results: Antibodies promoting opsonic phagocytosis of merozoites were cytophilic immunoglobulins (IgG1 and IgG3), induced monocyte activation and production of pro-inflammatory cytokines, and were directed against major merozoite surface proteins (MSPs). Consistent with protective immunity in humans, opsonizing antibodies were acquired with increasing age and malaria exposure, were boosted on re-infection, and levels were related to malaria transmission intensity. Opsonic phagocytosis was strongly associated with a reduced risk of clinical malaria in longitudinal studies in children with current or recent infections. In contrast, antibodies to the merozoite surface in standard immunoassays, or growth-inhibitory antibodies, were not significantly associated with protection. In multivariate analyses including several antibody responses, opsonic phagocytosis remained significantly associated with protection against malaria, highlighting its potential as a correlate of immunity. Furthermore, we demonstrate that human antibodies against MSP2 and MSP3 that are strongly associated with protection in this population are effective in opsonic phagocytosis of merozoites, providing a functional link between these antigen-specific responses and protection for the first time., Conclusions: Opsonic phagocytosis of merozoites appears to be an important mechanism contributing to protective immunity in humans. The opsonic phagocytosis assay appears to be a strong correlate of protection against malaria, a valuable biomarker of immunity, and provides a much-needed new tool for assessing responses to blood-stage malaria vaccines and measuring immunity in populations.

Tissue-engineered small-diameter vascular grafts have been developed as a promising alternative to native veins or arteries for replacement therapy. However, there is still a crucial need to improve the current approaches to render the tissue-engineered blood vessels more favorable for clinical applications. A completely biological blood vessel (3-mm inner diameter) was constructed by culturing a 50:50 mixture of bovine smooth muscle cells (SMCs) with neonatal human dermal fibroblasts in fibrin gels. After 30 days of culture under pulsatile stretching, the engineered blood vessels demonstrated an average burst pressure of 913.3±150.1 mmHg (n=6), a suture retention (53.3±15.4 g) that is suitable for implantation, and a compliance (3.1%±2.5% per 100 mmHg) that is comparable to native vessels. These engineered grafts contained circumferentially aligned collagen fibers, microfibrils and elastic fibers, and differentiated SMCs, mimicking a native artery. These promising mechanical and biochemical properties were achieved in a very short culture time of 30 days, suggesting the potential of co-culturing SMCs with fibroblasts in fibrin gels to generate functional small-diameter vascular grafts for vascular reconstruction surgery.

Introduction: Kinorhyncha is a clade of marine invertebrate meiofauna. Their body plan includes a retractable introvert bearing rings of cuticular spines, and a limbless trunk with distinct segmentation of nervous, muscular and epidermal organ systems. As derived members within the basal branch of Ecdysozoa, kinorhynchs may provide an important example of convergence on the evolution of segmentation within one of three bilaterian superclades. We describe the myoanatomy of Echinoderes, the most specious kinorhynch genus, and build upon historical studies of kinorhynch ultrastructure and gross morphology. This is the first multi-species comparison of a complete organ system by confocal microscopy and three-dimensional reconstruction within Kinorhyncha., Results: Myoanatomy of adult Echinoderes is composed of the following: Head with two mouth cone circular muscles, nine pairs of oral style muscles, ten introvert retractors, one introvert circular muscle, and fourteen introvert circular muscle retractors; Neck with one circular muscle; Trunk showing distinct pairs of ventral and dorsal muscles within segments 1-10, dorsoventral muscles within segments 3-10, diagonal muscles within segments 1-8, longitudinal fibers spanning segments 1-9, three pairs of terminal spine muscles, and one pair of male penile spine muscles; Gut showing a pharynx with ten alternating rings of radial and circular muscle fibers enclosed in a complex sheath of protractors and retractors, an orthogonal grid of longitudinal and circular fibers surrounding the intestine, and paired hindgut dilators., Conclusions: Myoanatomy is highly conserved between species of Echinoderes. Interspecific variation is observed in the arrangement and number of introvert fibers and the composition of pharyngeal muscles. Segmented trunk musculature facilitates the movements of articulated cuticular plates along the anterior-posterior axis. Intersegmental muscle fibers assist with dorsoventral and lateral trunk movements. Protractors, retractors and circular muscles coordinate eversion and retraction of the introvert and mouth cone, and relocation of the pharynx during locomotion and feeding behaviors. Pairs of posterior fibers suggest independent movements of terminal spines, and male penile spines. Within Scalidophora, myoanatomy is more similar between Kinorhyncha and Loricifera, than either group is to Priapulida. Kinorhynch myoanatomy may reflect a convergent transition from vermiform to segmented body plans during the early radiation of Ecdysozoa.

Plasmodium falciparum causes malaria disease during the asexual blood stages of infection when merozoites invade erythrocytes and replicate. Merozoite surface proteins (MSPs) are proposed to play a role in the initial binding of merozoites to erythrocytes, but precise roles remain undefined. Based on electron microscopy studies of invading Plasmodium merozoites, it is proposed that the majority of MSPs are cleaved and shed from the surface during invasion, perhaps to release receptor-ligand interactions. In this study, we demonstrate that there is not universal cleavage of MSPs during invasion. Instead, there is sequential and coordinated cleavage and shedding of proteins, indicating a diversity of roles for surface proteins during and after invasion. While MSP1 and peripheral surface proteins such as MSP3, MSP7, serine repeat antigen 4 (SERA4), and SERA5 are cleaved and shed at the tight junction between the invading merozoite and erythrocyte, the glycosylphosphatidylinositol (GPI)-anchored proteins MSP2 and MSP4 are carried into the erythrocyte without detectable processing. Following invasion, MSP2 rapidly degrades within 10 min, whereas MSP4 is maintained for hours. This suggests that while some proteins that are shed upon invasion may have roles in initial contact steps, others function during invasion and are then rapidly degraded, whereas others are internalized for roles during intraerythrocytic development. Interestingly, anti-MSP2 antibodies did not inhibit invasion and instead were carried into erythrocytes and maintained for approximately 20 h without inhibiting parasite development. These findings provide new insights into the mechanisms of invasion and knowledge to advance the development of new drugs and vaccines against malaria.

Sipuncula is an ancient clade of unsegmented marine worms that develop through a conserved pattern of unequal quartet spiral cleavage. They exhibit putative character modifications, including conspicuously large first-quartet micromeres and prototroch cells, postoral metatroch with exclusive locomotory function, paired retractor muscles and terminal organ system, and a U-shaped digestive architecture with left-right asymmetric development. Four developmental life history patterns are recognized, and they have evolved a unique metazoan larval type, the pelagosphera. When compared with other quartet spiral-cleaving models, sipunculan development is understudied, challenging and typically absent from evolutionary interpretations of spiralian larval and adult body plan diversity. If spiral cleavage is appropriately viewed as a flexible character complex, then understudied clades and characters should be investigated. We are pursuing sipunculan models for modern molecular, genetic and cellular research on evolution of spiralian development. Protocols for whole mount gene expression studies are established in four species. Molecular labeling and confocal imaging techniques are operative from embryogenesis through larval development. Next-generation sequencing of developmental transcriptomes has been completed for two species with highly contrasting life history patterns, Phascolion cryptum (direct development) and Nephasoma pellucidum (indirect planktotrophy). Looking forward, we will attempt intracellular lineage tracing and fate-mapping studies in a proposed model sipunculan, Themiste lageniformis. Importantly, with the unsegmented Sipuncula now repositioned within the segmented Annelida, sipunculan worms have become timely and appropriate models for investigating the potential for flexibility in spiralian development, including segmentation. We briefly review previous studies, and discuss new observations on the spiralian character complex within Sipuncula.

Background: While recent studies have shown patients with developmental dysplasia of the hip (DDH) undergoing total hip arthroplasty (THA) to achieve comparable post-operative outcomes to patients with primary osteoarthritis (OA), it is unclear whether DDH patients display better or worse preoperative function than the general THA population. We aimed to compare the preoperative function and functional response to THA of DDH patients with OA patients., Methods: Through a retrospective review of prospectively collected regional joint registry data, we compared the preoperative, 1-year post-operative and post-operative change in disease-specific (Oxford hip score (OHS), Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC)) and general health (short form 12 physical health (SF-12 PH), mental health (SF-12 MH) scores) functional scores of 33 DDH patients and 968 OA patients undergoing primary THA., Results: The DDH group displayed substantially worse preoperative function than the OA group (mean OHS 11.2 versus 16.3 (P = 0.001), WOMAC 72.7 versus 60.6 (P < 0.001), SF-12 PH 27.8 versus 28.9 (P = 0.433), SF-12 MH 35.5 versus 44.7 (P < 0.001)). Functional response to THA at 1 year was significantly better in the DDH group than the OA group (mean score improvements: OHS 31.1 versus 24.6 (P < 0.001), WOMAC 61.4 versus 47.2 (P < 0.001), SF-12 PH 22.3 versus 16.5 (P = 0.003), SF-12 MH 18.4 versus 8.4 (P < 0.001))., Conclusion: Despite experiencing significantly worse preoperative function, DDH patients undergoing THA demonstrated superior early functional response to OA patients, with substantially greater improvements observed in all disease-specific and general health outcome measures., (© 2012 The Authors. ANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons.)

Background: Although cardiac risk prediction is widely used in various clinical settings, its potential role in enhancing prehospital triage is yet to be understood., Objective: To systematically review the diagnostic accuracy of short-term clinical prediction models for potential use in a prehospital population with suspected acute coronary syndrome., Methods: Eleven electronic medical databases were searched from 1990 to the end of August 2010 for all English-language observational and interventional studies. An online search strategy tool was used to identify grey-literature studies. Eligibility criteria were: 1) an unselected population of adult acute coronary syndrome patients; 2) recruited within the Emergency Department or Emergency Medical Services; 3) reported multivariate analysis encompassing patient history or physical examination; 4) reported short-term outcome measures; 5) were not solely computer protocols; and 6) were not reliant on tests unavailable out of the hospital. Data extraction was conducted by a single reviewer and verified by a second reviewer. Study quality was assessed independently by two reviewers using a validated quality assessment tool., Results: A total of seven clinical prediction models were identified. Only two models reported were derived from a prehospital study population. Six clinical prediction models described good discriminate abilities (c-statistic) of 0.72 to 0.87. Among the range of independent predictors identified, electrocardiogram abnormalities, age, heart rate, and systolic blood pressure provided the strongest prognostic information., Conclusion: The models identified provided reasonable diagnostic accuracy for determining short-term outcomes. Methodological weaknesses and variability in the populations investigated limit their use in clinical practice., (Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the reliability (inter- and intra-observer variability) of 4 hip anatomies using 2-dimensional pelvic computed tomography (CT)., Methods: Two-dimensional pelvic CT of 10 men and 10 women aged 33 to 89 (mean, 69) years presenting with non-orthopaedic conditions within one month were evaluated by 3 observers. The centre-edge angle of Wiberg, the Sharp angle, the acetabular depth ratio of Murray, and the acetabular anteversion angle of every hip were measured by each observer. After 6 weeks, these measurements were repeated. Reliability was evaluated using intraclass correlation coefficient (ICC), which represents the variation between patients as a percentage of the variation from all 3 sources (patients, inter-observers, and intra-observers). The ICC was classified as poor (<0.20), fair (0.21-0.40), moderate (0.41-0.60), substantial (0.61-0.80), and excellent (0.81-1.00)., Results: Reliability was substantial for the Sharp angle (ICC=0.74), the acetabular anteversion angle (ICC=0.69), and the acetabular depth ratio of Murray (ICC=0.62), and was fair for the centre-edge angle of Wiberg (ICC=0.40)., Conclusion: The Sharp angle, the acetabular anteversion angle, and the acetabular depth ratio of Murray could be reliably measured using 2-dimensional CT. These measurements are appropriate for population-based studies of hip anatomy.

Aim: The objective of this study was to determine if undergraduate paramedics could accurately perform common drug calculations and basic mathematical computations normally required in the workplace., Method: A descriptive paper-based questionnaire collecting demographical data, student attitudes regarding their drug calculation performance, and answers to a series of basic mathematical and drug calculation questions was administered to undergraduate paramedic students., Results: The mean score was 39.5% with only 3.3% of students (n=3) scoring greater than 90%, and 63% (n=58) scoring 50% or less. Conceptual errors made up 48.5%, arithmetical 31.1% and computational 17.4%., Conclusion: This study suggests undergraduate paramedics have deficiencies in performing accurate calculations with conceptual errors indicating a fundamental lack of mathematical understanding.

Purpose: Scapulothoracic bursitis is a painful condition of the scapulothoracic articulation, which may be caused by various pathological anatomical associations. We have arthroscopically observed a constant bare area of bone on the costal scapula surface in patients with scapulothoracic bursitis, contradictory to traditional anatomical reports of scapular muscle relations. We undertook a cadaveric study to further define this anatomical feature., Methods: Twelve cadaveric shoulders were dissected. The costal surface of the scapula was systematically examined for the presence of a superomedial bare area in each shoulder by three independent clinicians, with dimensions measured using digital calipers., Results: In all shoulders, there was a clearly defined bare area of bone on the superomedial aspect of the costal surface of the scapula between the serratus anterior insertion and subscapularis origin. The bare area was typically crescenteric in shape, with variable length (mean 22.3 ± 6.0 mm) and width (10.8 ± 2.8 mm). The bare area length (p = 0.043) and width (p = 0.033) were significantly greater in female shoulders compared to male shoulders., Conclusions: We have established the presence of the superomedial bare area of the costal scapula surface. With an absence of overlying subscapularis muscle, this bare area carries the potential for scapulothoracic impingement, and should be considered as a possible aetiological factor in all patients presenting with scapulothoracic bursitis.

Cycloneuralian taxa exhibit similar organ system architectures, providing informative characters of metazoan evolution, yet very few modern comparative descriptions of cellular and molecular homologies within and among those taxa are available. We immunolabeled and characterized elements of the serotonergic nervous system in the kinorhynchs Echinoderes spinifurca, Antygomonas paulae, and Zelinkaderes brightae using confocal laser scanning microscopy. Fluorescent markers targeting DNA were combined with observations of auto-fluorescent structures to guide interpretations of the internal and external anatomy in each species. Results show a common pattern of the central nervous system with a circumenteric brain divided into ring-shaped anterior and posterior neuronal somata and a central neuropil connected to a multi-stringed, longitudinal ventral nerve cord. Structural similarities and differences in the nervous systems of these species were observed and described, stressing the incomplete ring nature of the anterior region of the kinorhynch brain, the functional relationship between the brain and the movable introvert, and the number and arrangement of nerve strings and somata of the ventral nerve cord. The ventral cord ends in two ventrolateral cell bodies in E. spinifurca, and forms a terminal loop associated with a midterminal spine in A. paulae and Z. brightae. The possible functional and phylogenetic significance of these features and arrangements are discussed., (Copyright © 2012 Wiley Periodicals, Inc.)

Background: The accurate assessment of a patient's conscious state using the Glasgow Coma Scale (GCS) is an important skill for paramedics as it may determine the patient's initial and ongoing management. The objective of this study was to determine if undergraduate paramedic students from a large Australian University were able to accurately interpret a variety of conscious states., Methods: A prospective double-blinded observational pilot study requiring students to interpret the conscious state of four adult patients using the GCS by viewing a simulation DVD package., Results: There were 137 students who participated in the study, of whom 65% (n=87) were female students. The results demonstrated that undergraduate paramedic students were unable to accurately interpret a number of patient conscious states with only 20% and 37% of students able to accurately identify the GCS of patients 2 (GCS=12) and 3 (GCS=7). The motor component of the GCS appeared to be the component where the least accurate interpretation occurred, with only 47% of students being able to accurately identify the criteria that patient 3 displayed. Participants were however able to accurately interpret the GCS of both patient 1 (GCS=14) (86%) and patient 4 (GCS=15) (92%)., Conclusion: This pilot study demonstrates that undergraduate paramedic students from an Australian university were unable to accurately interpret a patient's conscious state if their GCS score was <14. These findings have provided academic staff with important information for considering alternative teaching and learning strategies and approaches in conscious state assessment in current paramedic curricula.

Merozoite invasion of human red blood cells by Plasmodium falciparum is essential for blood stage asexual replication and the development of malaria disease. Despite this, many of the processes involved in invasion are poorly understood. Recent advances have been made in methods to isolate viable merozoites for studies of invasion. The application of these approaches is providing new insights into the kinetics of invasion and merozoite survival, as well as proteins and interactions involved in invasion, and will facilitate the development and testing of anti-merozoite vaccines and the identification of invasion-inhibitory compounds with potential for drug development. This review discusses these recent advances and considers potential avenues for future research., (Copyright © 2012 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.)