A combination of new screening assays for prioritization of transmission-blocking antimalarials reveals distinct dynamics of marketed and experimental drugs.

OBJECTIVES: The development of drugs to reduce malaria transmission is an important part of malaria eradication plans. We set out to develop and validate a combination of new screening assays for prioritization of transmission-blocking molecules. METHODS: We developed high-throughput assays for screening compounds against gametocytes, the parasite stages responsible for onward transmission to mosquitoes. An existing gametocyte parasitic lactate dehydrogenase (pLDH) assay was adapted for use in 384-well plates, and a novel homogeneous immunoassay to monitor the functional transition of female gametocytes into gametes was developed. A collection of 48 marketed and experimental antimalarials was screened and subsequently tested for impact on sporogony in Anopheles mosquitoes, to directly quantify the transmission-blocking properties of antimalarials in relation to their effects on gametocyte pLDH activity or gametogenesis. RESULTS AND CONCLUSIONS: The novel screening assays revealed distinct stage-specific kinetics and dynamics of drug effects. Peroxides showed the most potent transmission-blocking effects, with an intermediate speed of action and IC50 values that were 20-40-fold higher than the IC50s against the asexual stages causing clinical malaria. Finally, the novel synthetic peroxide OZ439 appeared to be a promising drug candidate as it exerted gametocytocidal and transmission-blocking effects at clinically relevant concentrations.

Lead clinical and preclinical antimalarial drugs can significantly reduce sporozoite transmission to vertebrate populations.

To achieve malarial elimination, we must employ interventions that reduce the exposure of human populations to infectious mosquitoes. To this end, numerous antimalarial drugs are under assessment in a variety of transmission-blocking assays which fail to measure the single crucial criteria of a successful intervention, namely impact on case incidence within a vertebrate population (reduction in reproductive number/effect size). Consequently, any reduction in new infections due to drug treatment (and how this may be influenced by differing transmission settings) is not currently examined, limiting the translation of any findings. We describe the use of a laboratory population model to assess how individual antimalarial drugs can impact the number of secondary Plasmodium berghei infections over a cycle of transmission. We examine the impact of multiple clinical and preclinical drugs on both insect and vertebrate populations at multiple transmission settings. Both primaquine (>6 mg/kg of body weight) and NITD609 (8.1 mg/kg) have significant impacts across multiple transmission settings, but artemether and lumefantrine (57 and 11.8 mg/kg), OZ439 (6.5 mg/kg), and primaquine (<1.25 mg/kg) demonstrated potent efficacy only at lower-transmission settings. While directly demonstrating the impact of antimalarial drug treatment on vertebrate populations, we additionally calculate effect size for each treatment, allowing for head-to-head comparison of the potential impact of individual drugs within epidemiologically relevant settings, supporting their usage within elimination campaigns.

A male and female gametocyte functional viability assay to identify biologically relevant malaria transmission-blocking drugs.

Malaria elimination will require interventions that prevent parasite transmission from the human host to the mosquito. Experimentally, this is usually determined by the expensive and laborious Plasmodium falciparum standard membrane feeding assay (PfSMFA), which has limited utility for high-throughput drug screening. In response, we developed the P. falciparum dual gamete formation assay (PfDGFA), which faithfully simulates the initial stages of the PfSMFA in vitro. It utilizes a dual readout that individually and simultaneously reports on the functional viability of male and female mature stage V gametocytes. To validate, we screen the Medicines for Malaria Venture (MMV) Malaria Box library with the PfDGFA. Unique to this assay, we find compounds that target male gametocytes only and also compounds with reversible and irreversible activity. Most importantly, we show that compound activity in the PfDGFA accurately predicts activity in PfSMFAs, which validates and supports its adoption into the transmission-stage screening pipeline.

[18F]-FBEM, a tracer targeting cell-surface protein thiols for cell trafficking imaging.

We used [(18)F]-4-fluorobenzamido-N-ethylamino-maleimide ([(18)F]-FBEM) to radiolabel cells ex vivo for in vivo positron emission tomography (PET) in order to assess cell trafficking in mice. In contrast to commonly used imaging agents, [(18)F]-FBEM forms a covalent bond with thiol groups present on the cells surface. The stability of the probe in aqueous medium was tested at different pH values and cross-experiment showed that thiol-labeling efficiency was retained (at least) up to pH 9. The labeling procedure did not affect significantly the cell viability. To illustrate the procedure, PET images of living mice injected intravenously with labeled T lymphocytes were obtained. They showed the expected cell homing in the spleen that was absent in mice injected with free label.

Coordination profiles of the expert field hockey drive according to field roles.

The aim of this study was to determine coordination profiles for the field hockey drive. Nine elite female players performed five drives each. They were asked to primarily maximize ball placement accuracy, and secondly to drive with high velocity. An optical motion capture system recorded the displacement of six markers on the joints of the players' arms as they performed the drives, and a radar gun measured the ball velocity after impact. Spatial, temporal, and velocity variables were then established. Discrete relative phases were also established at ball impact to examine medio-lateral and proximo-distal upper-arms coordination. The high standard deviation values in joint kinematics were indicative of inter-individual variability, i.e. several drive solutions. Cluster analysis was thus used and two profiles among the players were identified. For the two profiles, the global coordination pattern of movement (upper-arm coordination) was in-phase for the right arm, and out-of-phase for the left lead arm, suggesting a segmental sequencing. However, differences were noted on local kinematic parameters which led to the following categorization: the 'strong group' for defenders and the 'temporal-effectiveness group' for midfielders and forwards. The results support the value of individual analysis to better interpret and contrast the distinct roles of expert players.

[Congenital erythropoeietic porphyria treated by haematopoietic stem cell allograft]. / Porphyrie érythropoïétique congénitale traitée par allogreffe de cellules souches hématopoïétiques.

BACKGROUND: Congenital erythropoietic porphyria (CEP) is a genodermatosis associated uroporphyrinogen III synthase deficit that results in porphyrin accumulation in various organs, particularly the skin. It is the most severe form of porphyria associated with haemolytic anaemia and cutaneous phototoxicity. We report a severe case of CEP treated by allogeneic bone marrow transplantation. CASE REPORT: A one-year-old child presented erythrodontia and scarring on exposed areas. The diagnosis of CEP was confirmed by the decline of uroporphyrinogen III synthase activity. Demonstration of p.Cys73Arg mutation confirmed the severity of the disease. Allogeneic bone marrow transplantation resulted in persistent resolution of clinical signs 25 months after grafting. DISCUSSION: Symptomatic treatment is ineffective in this serious disease associated with early mortality. 11 of the 13 patients treated by allogeneic hematopoietic stem cell graft, including our patient, continued to be asymptomatic an average of seven years after transplantation. CONCLUSION: This new case confirms the role of allogeneic hematopoietic stem cell grafting in the treatment of congenital erythropoietic porphyria.

[Intracranial extension of cutaneous facial squamous cell carcinoma: involvement of the neurotropic pathway]. / Extension intracrânienne d'un carcinome spinocellulaire de la face : implication de la voie neurotrope.

BACKGROUND: Squamous cell carcinoma is the most common form of skin cancer after basal cell carcinoma. It comprises locoregional malignant tumours with more rapid and severe spread, and which may metastasise through blood or lymph, and through a less well-known neurotropic pathway. We report a case of late and slowly progressive recurrence of squamous cell carcinoma revealed and characterized by neurological symptoms alone. OBSERVATION: A 69-year-old woman with a history of cutaneous squamous cell carcinoma on the left nostril edge removed 10 years earlier presented right trigeminal neuralgia in 2003. These symptoms gradually expanded and in 2007 a subcutaneous induration of the two cheeks appeared. Magnetic resonance imaging (MRI) showed subcutaneous infiltration of the 2 nasolabial sulci, as did contrast enhancement of the two trigeminal nerves up to the cavernous sinuses. Deep biopsy allowed a diagnosis of invasive squamous cell carcinoma to be made. DISCUSSION: Neurotropism is an important feature of squamous cell carcinoma, and reveals the aggressive nature of this condition. This feature makes it hard to diagnose relapse since the neurological symptoms may be isolated for a long period, hence the need for systematic screening for perineural tumour sites on histological analysis of the initial lesion. Treatment for these forms is limited and for the moment consists of radiation, cetuximab and a combination of these two treatments.

Factors associated with emergence of pristinamycin-resistant Staphylococcus aureus in a dermatology department: a case-control study.

BACKGROUND: Pristinamycin is used for the treatment of Staphylococcus aureus skin infection. Staphylococcus aureus pristinamycin resistance is usually low. The frequency of pristinamycin-resistant S. aureus (PRSA) increased in the Caen University Hospital dermatology department from 1% in 1998 to >11% in 1999-2002. OBJECTIVES: This study aimed to identify the factors associated with PRSA acquisition. METHODS: Incidences of PRSA and pristinamycin consumption were calculated for the dermatology department and for the rest of the hospital from 1997 to 2007. Individual factors of PRSA acquisition in the dermatology department from 2000 to 2001 were analysed in a retrospective case-control study including 23 cases of PRSA skin colonization or infection and 46 controls with pristinamycin-susceptible S. aureus. Clonal relatedness of isolates was analysed by pulsed-field gel electrophoresis and pristinamycin resistance genes were detected by polymerase chain reaction. Conditional logistic regression was performed to analyse the relationship between pristinamycin resistance and epidemiological and microbiological data. RESULTS: PRSA frequency and pristinamycin consumption were significantly higher in the dermatology department than in other hospital departments. Two epidemic clones of two and six isolates were found for periods of 1 and 2 months, respectively. Thirteen of the 23 PRSA isolates (57%), including all isolates of the two epidemic clones, were found 48 h after the hospitalization or later. PRSA was associated with pristinamycin use during the previous year [odds ratio (OR) 5.60, 95% confidence interval (CI) 1.41-22.22], cumulative use of antibiotics exceeding 1 week during the previous year (OR 4.63, 95% CI 1.47-14.54) and methicillin resistance (OR 6.35, 95% CI 1.38-29.15). CONCLUSIONS: Results suggest that antimicrobial selective pressure and microbial cross-transmission are involved in PRSA acquisition.

Epstein-Barr virus involvement in the pathogenesis of hydroa vacciniforme: an assessment of seven adult patients with long-term follow-up.

BACKGROUND: Hydroa vacciniforme (HV) is a chronic papulovesicular photodermatosis of childhood, with some cases persisting through adulthood. In children, the Epstein-Barr virus (EBV) has been detected in typical HV and in HV evolving into natural killer/T-cell lymphoma. No exploration of EBV infection has been performed in adult patients with HV with long-term follow-up. OBJECTIVES: To assess EBV infection systematically in blood and in experimentally photoinduced lesions in adult patients with HV. METHODS: Repeated tests for EBV DNA blood load using real-time polymerase chain reaction (PCR) and serological EBV tests were performed in seven adult patients with long-term follow-up. Skin samples from phototest-induced lesions and surrounding normal skin were studied using PCR, in situ hybridization and electron microscopy. ZEBRA protein was detected using immunostaining. Thirty-five patients with other photosensitive disorders were included as controls. RESULTS: The EBV DNA blood load was strongly positive in the seven patients with HV and negative in 34 of 35 of the patients with other photosensitive disorders (P < 0.001). The levels were higher in photosensitive patients with HV than in patients with HV in clinical remission. Ultrastructurally, viral particles were detected in lymphocytes and also in keratinocytes in three experimentally phototest-induced lesions; they were not found in the surrounding normal skin. ZEBRA protein was also detected in phototest-induced lesions, but not in the surrounding normal skin. CONCLUSION: EBV is involved in HV pathogenesis and persists in adult patients with HV. A positive EBV DNA load, specific to HV in the spectrum of photosensitive disorders, might be a useful biomarker in HV.

Multifocal aggressive squamous cell carcinomas induced by prolonged voriconazole therapy: a case report.

Voriconazole is a treatment for severe fungal infections. Prolonged voriconazole therapy may induce skin reactions, with 1% of severe photosensitivity accidents. Recently the imputability of voriconazole in skin carcinogenesis has been suggested. This report concerns a 55-year-old man suffering from pulmonary aspergillosis who presented a phototoxic reaction a few months after introduction of voriconazole, followed by multiple squamous cell carcinomas of sun-exposed skin areas. After voriconazole discontinuation, no new carcinoma was observed. The detection of EBV and HPV in skin lesions was negative. Exploration of gene mutations involved in skin carcinogenesis showed two variants of the MICR gene. The occurrence of multiple, recurrent, aggressive squamous cell carcinomas is rare with voriconazole, but its imputability is strongly suggested. A plausible hypothesis is that several factors including voriconazole uptake, immunosuppression, and genetic background could explain the phenotype of fast-developing skin carcinomas. Voriconazole therapy should be accompanied by stringent photoprotection and skin monitoring.

Development of ecotoxicoproteomics on the freshwater amphipod Gammarus pulex: identification of PCB biomarkers in glycolysis and glutamate pathways.

PCBs are persistent organic pollutants largely distributed in the biosphere. Although their effects on vertebrates are well described, little is known about their action on freshwater invertebrate's metabolism. Gammarus pulex (Linné) was selected as an indicator model to develop a proteomic approach in order to characterize the effects of PCBs on the protein profile of this freshwater crustacean. Sublethal coplanar PCBs exposition and related 2D gel were performed. More than 560 spots were detected and a total of 21 proteins exhibiting significant expression differences in PCB exposed to G. pulex were identified by mass spectrometry. Database searches were conducted to relate the results to well-known metabolic pathways (pentose phosphate, cytoskeleton, energy, etc.). In particular, glyceraldehyde 3-phosphate dehydrogenase and arginine kinase were found to be sensitive to the PCB exposition of G. pulex. The aim of the present study was to assess the biochemical responses and the metabolic changes in G. pulex following intoxication to coplanar PCB congeners CB77 and CB169 by a proteomic approach. This approach allowed us, by the identification of key proteins, to highlight important biochemical mechanisms disturbed by the presence of these contaminants in G. pulex.

Prevalence and risk factors of the whole spectrum of sexually transmitted diseases in male incoming prisoners in France.

Sexually transmitted diseases (STD) are a public health issue in prison. As inmates are eventually released, it is also a community concern. There are very few data on the entire spectrum of STDs, particularly condyloma among prisoners. To determine the prevalence of all STDs: infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), herpes simplex virus (HSV), Chlamydia trachomatis, Neisseria gonorrhoea, syphilis, and condyloma among entering inmates. A cross-sectional study was conducted in France from November 2000 to June 2003. Male adults entering a prison remand center in Caen had a medical consultation and physical examination including external genital organs and perianal area for condyloma and herpes infection, a urethral swab for Chlamydia trachomatis and Neisseria gonorrhoea detection, and a blood sample for HBV, HCV, HIV, and syphilis serology. Five hundred and ninety-seven inmates agreed to participate in the study. Sixteen percent had at least one STD: 4.0% had condyloma, 4.0% chlamydia infection, and 4.9% were positive for HCV antibodies. Two had early syphilis and 1 had acute HBV, but no HIV infection, neither genital herpes nor gonorrhea. The analysis of the STD risk behaviors did not show any difference between the infected and uninfected participants, except that HCV-positive participants were more likely to be intravenous drug users. Results suggest that a systematic screening of all STDs should be at least proposed to every entering inmate since no demographic or sexual characteristics are consistently associated with STDs.

[Mucosal involvement in lymphomatoid papulosis: four cases]. / Atteinte muqueuse dans la papulose lymphomatoïde: quatre cas.

BACKGROUND: Lymphomatoid papulosis is a form of CD30+ cutaneous lymphoproliferation characterized by a benign chronic papulonodular eruption that regresses spontaneously. The clinical features contrast with the malignant histological aspect of lesions. Mucosal lesions are rare, with less than 10 published cases. We report four new cases and we highlight characteristic features of lesions at this particular site. PATIENTS AND METHODS: We report four cases of mucous lymphomatoid papulosis in three women aged 37, 38, and 71 years and one 66-year-old man. These cases were collated from three different hospitals: Orléans, Rouen and Caen. Mucosal lesions occurred after cutaneous eruption in two cases but remained isolated or preceded cutaneous lesions in the other two cases. The main site was the mouth in all four cases but one case also involved genital lesions. Two cases involved type A pathological features and two had type C features. Association with lymphoma was excluded on clinical, laboratory and radiological examination. One patient was treated with methotrexate (>7.5mg/week) and did not relapse. Of the three other untreated patients only one did not relapse (short 14-month follow-up). DISCUSSION: Recurrent oral ulcerations may be mucosal manifestations of lymphomatoid papulosis. This site does not appear to have any bearing on prognosis.

Postural organisation during cascade juggling: influence of expertise.

The present study investigated how posture is organised during three-ball cascade juggling according to expertise. We hypothesized that the juggling task would place constraints on the postural organisation mode and that the posture-juggling coupling would be increased with expertise. Two groups, intermediates and experts, were asked to perform a postural-cascade juggling task. A three-dimensional motion recording system recorded the position of five light-reflecting markers for 30s to analyse the ball movements, the lateral oscillations of the sacrum and the flexion/extension of the right elbow. The spatial pattern of the cascade juggling showed no significant difference between groups. Moreover, both groups presented lateral oscillations of the sacrum during the task. The latencies between the maximal flexion/extension of the right elbow and the maximal lateral oscillations of the sacrum and their standard deviations were significantly lower for the experts than for the intermediates. We conclude that postural adaptations occur to facilitate the postural-suprapostural task and that experience modifies the posture-juggling coupling.

[Purely cutaneous Rosai-Dorfman disease present for 19 years]. / Maladie de Rosai-Dorfman cutanée pure évoluant depuis 19 ans.

BACKGROUND: Rosai-Dorfman disease is a non-Langerhans histiocytosis chiefly affecting lymph nodes sites. In rare cases, it presents in the form of isolated skin lesions, without adenopathy, in which case it is a benign disease that regresses spontaneously within our number of months and years. PATIENTS AND METHODS: An 83 year-old man presented with multiple red-brown nodular lesions on the upper part of the body that had been progressing over a period of 19 years. Histological examination showed infiltrate characteristic of Rosai-Dorfman disease, with numerous dermal foci of histiocytes expressing protein S100 but not expressing CD1a on immunohistochemical analysis, as well as emperipolesis. The lymph nodes sites were unaffected, and the remainder of the clinical and laboratory examinations were normal, indicating a purely cutaneous form of the disease. Treatment with isotretinoin was ineffective and the lesions continued to spread gradually, being treated from time to time with CO2 laser or cryotherapy. DISCUSSION: Our case is atypical in terms of clinical presentation since it involved diffuse nodular lesions. The disease course was also unusual in that no spontaneous regression was observed even after 19 years.

Morphological evidence for direct interaction between gonadotrophin-releasing hormone neurones and astroglial cells in the human hypothalamus.

In rodents, there is compelling evidence indicating that dynamic cell-to-cell communications involving cross talk between astroglial cells (such as astrocytes and specialised ependymoglial cells known as tanycytes) and neurones are important in regulating the secretion of gonadotrophin-releasing hormone (GnRH), the neurohormone that controls both sexual maturation and adult reproductive function. However, whether such astroglial cell-GnRH neurone interactions occur in the human brain is not known. In the present study, we used immunofluorescence to examine the anatomical relationship between GnRH neurones and glial cells within the hypothalamus of five women. Double-staining experiments demonstrated the ensheathment of GnRH neurone perikarya by glial fibrillary acidic protein (GFAP)-immunoreactive astrocyte processes in the periventricular zone of the tuberal region of the hypothalamus. GFAP immunoreactivity did not overlap that of GnRH at the GnRH neurone's projection site (i.e. the median eminence of the hypothalamus). Rather, human GnRH neuroendocrine fibres were found to be closely associated with vimentin or nestin-immunopositive radial glial processes likely belonging to tanycytes. In line with these light microscopy data, ultrastructural examination of GnRH-immunoreactive neurones showed numerous glial cells in direct apposition to pre-embedding-labelled GnRH cell bodies and/or dendrites in the infundibular nucleus, whereas postembedding immunogold-labelled GnRH nerve terminals were often seen to be enwrapped by glial cell processes in the median eminence. GnRH nerve button were sometimes visualised in close proximity to fenestrated pituitary portal blood capillaries and/or evaginations of the basal lamina that delineate the pericapillary space. In summary, these data demonstrate that GnRH neurones morphologically interact with astrocytes and tanycytes in the human brain and provide evidence that glial cells may contribute physiologically to the process by which the neuroendocrine brain controls the function of GnRH neurones in humans.

The effect of combined self- and expert-modelling on the performance of the double leg circle on the pommel horse.

In this study, we investigated whether video modelling can enhance gymnasts' performance of the circle on a pommel horse. The procedure associated expert-modelling with self-modelling and quantitative performance analysis. Sixteen gymnasts were randomly assigned to one of two groups: (1) a modelling group, which received expert- and self-modelling, and performance feedback, or (2) a control group, which received no feedback. After five sessions of training, an analysis of variance with repeated measures indicated that the gains in the back, entry, front, and exit phases of the circle were greater for the modelling group than for the control group. During the training sessions, the gymnasts in the modelling group improved their body segmental alignment during the back phase more quickly than during the other phases. As predicted, although both groups performed the same number of circles (300 in 5 days, with 10 sequences of 6 circles), the modelling group improved their body segmental alignment more than the control group. It thus appears that immediate video modelling can help to correct complex sports movements such as the circle performed on the pommel horse. However, its effectiveness seemed to be dependent on the complexity of the phase.

Sexual dimorphism in the organization of the rat hypothalamic infundibular area.

The hypothalamic infundibular area is located outside the blood-brain barrier and includes, the ventromedial arcuate nucleus (vmARC) sensing circulating substances, and the median eminence (ME) where neurohormones are released into the hypothalamo-hypophysial vasculature. This integrated functional unit, pivotal in endocrine control, adjusts neuroendocrine output to feedback information. Despite a differing physiology in males and females, this functional unit has not appeared differently organized between sexes. Using immunocytochemistry, we describe here for the first time in adult rats, a conspicuous sex-difference in its axonal wiring by intrinsic glutamatergic neurons containing the neuropeptides neurokinin B (NKB) and dynorphin. In the male, NKB neurons send axons to capillary vessels of the vmARC and of the ME (only where gonadotropin-releasing hormone (GnRH) axons terminate). Electron microscopy revealed that NKB axons target the barrier of tanycytes around fenestrated capillary vessels (in addition to GnRH axons), suggesting a control of regional bidirectional permeability. In the female, NKB neurons send axons to the neuropile of the vmARC, suggesting a direct control of its sensor neurons. The other projections of NKB neurons, studied by surgical isolation of the ARC-ME complex and confocal microscopy, are not sexually dimorphic and target both integrative and neuroendocrine centers controlling reproduction and metabolism, suggesting a broad influence over endocrine function. These observations demonstrate that the mechanisms subserving hypothalamic permeability and sensitivity to feedback information are sexually dimorphic, making the infundibular area a privileged site of generation of the male-to-female differences in the adult pattern of pulsatile hormonal secretions.

[Incidence of drug-induced photosensitization during phototherapy]. / Incidence des accidents par photosensibilisation médicamenteuse au cours des photothérapies.

BACKGROUND: Exogenous photosensitization represents one of the adverse effects of phototherapy. However, the impact of potentially photosensitizing drugs on the incidence of photo-induced eruptions during phototherapy is unknown. AIM OF THE STUDY: To determine the incidence of drug photosensitization during phototherapy. PATIENTS AND METHODS: This was a retrospective study of all patients undergoing phototherapy between November 1999 and April 2004 in the Dermatology Department of Caen University Teaching Hospital. Details of all topical or systemic medications taken before or during phototherapy were recorded. Since methoxsalen induces photosensitization, sessions of phototherapy were stratified according to whether methoxsalen was given. Screening was performed for the following clinical signs of drug photosensitization: acute photo-induced, erythematous and/or vesicular eruption, associated with pruritus or burning. RESULTS: In the non-methoxsalen group, use of a potentially photosensitizing drug was found for 29/155 TL01 phototherapy sessions. Drug-induced photosensitization was suspected in 3/29 sessions (10.3%). In the methoxsalen group, a potentially photosensitizing drug was found in 21/118 sessions of PUVA-therapy. Drug-induced photosensitization was suspected in 4/21 sessions (19%). Risk of photo-induced eruption was not associated with photosensitizing drug therapy, TL01 phototherapy or PUVA-therapy. DISCUSSION: Drug photosensitization appears to be rare during phototherapy, regardless of photosensitizing drug intake. It is twice as frequent during PUVA-therapy as during TL01 phototherapy but this difference is not significant.