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Clostridium dakarense strain FF1(T), is the type strain of Clostridium dakarense sp. nov., a new species within the genus Clostridium. This strain, whose genome is described here, was isolated from the fecal flora of a 4-month-old Senegalese child suffering from gastroenteritis. C. dakarense sp. nov. strain FF1(T) is an obligate anaerobic Gram-positive bacillus. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 3,735,762 bp long genome (1 chromosome but no plasmid) exhibits a G+C content of 27.98% and contains 3,843 protein-coding and 73 RNA genes, including 8 rRNA genes.

Fibered confocal fluorescence in vivo imaging with a fiber optic bundle uses the same principle as fluorescent confocal microscopy. It can excite fluorescent in situ elements through the optical fibers, and then record some of the emitted photons, via the same optical fibers. The light source is a laser that sends the exciting light through an element within the fiber bundle and as it scans over the sample, recreates an image pixel by pixel. As this scan is very fast, by combining it with dedicated image processing software, images in real time with a frequency of 12 frames/sec can be obtained. We developed a technique to quantitatively characterize capillary morphology and function, using a confocal fluorescence videomicroscopy device. The first step in our experiment was to record 5 sec movies in the four quadrants of the tumor to visualize the capillary network. All movies were processed using software (ImageCell, Mauna Kea Technology, Paris France) that performs an automated segmentation of vessels around a chosen diameter (10 μm in our case). Thus, we could quantify the 'functional capillary density', which is the ratio between the total vessel area and the total area of the image. This parameter was a surrogate marker for microvascular density, usually measured using pathology tools. The second step was to record movies of the tumor over 20 min to quantify leakage of the macromolecular contrast agent through the capillary wall into the interstitium. By measuring the ratio of signal intensity in the interstitium over that in the vessels, an 'index leakage' was obtained, acting as a surrogate marker for capillary permeability.

Background: The Northern part of Senegal is characterized by a low and seasonal transmission of malaria. However, some Plasmodium falciparum infections and malaria clinical cases are reported during the dry season. This study aims to assess the relationship between IgG antibody (Ab) responses to gSG6-P1 mosquito salivary peptide and the prevalence of P. falciparum infection in children during the dry season in the Senegal River Valley. The positive association of the Ab response to gSG6-P1, as biomarker of human exposure to Anopheles vector bite, and P. falciparum infectious status (uninfected, infected-asymptomatic or infected-symptomatic) will allow considering this biomarker as a potential indicator of P. falciparum infection risk during the dry season., Methods: Microscopic examination of thick blood smears was performed in 371 and 310 children at the start (January) and at the end (June) of the dry season, respectively, in order to assess the prevalence of P. falciparum infection. Collected sera were used to evaluate IgG response to gSG6-P1 by ELISA. Association between parasitological and clinical data (infected-asymptomatic or infected-symptomatic) and the anti-gSG6-P1 IgG levels were evaluated during this period., Results: The prevalence of P. falciparum infection was very low to moderate according to the studied period and was higher in January (23.5%) compared to June (3.5%). Specific IgG response was also different between uninfected children and asymptomatic carriers of the parasite. Children with P. falciparum infection in the dry season showed higher IgG Ab levels to gSG6-P1 than uninfected children., Conclusions: The results strengthen the hypothesis that malaria transmission is maintained during the dry season in an area of low and seasonal transmission. The measurement of IgG responses to gSG6-P1 salivary peptide could be a pertinent indicator of human malaria reservoir or infection risk in this particular epidemiological context. This promising immunological marker could be useful for the evaluation of the risk of P. falciparum exposure observed during dry season and, by consequences, could be used for the survey of potential pre-elimination situation.

Background: Over the past decade, a sharp decline of malaria burden has been observed in several countries. Consequently, the conventional entomological methods have become insufficiently sensitive and probably under-estimate micro-geographical heterogeneity of exposure and subsequent risk of malaria transmission. In this study, we investigated whether the human antibody (Ab) response to Anopheles salivary gSG6-P1 peptide, known as a biomarker of Anopheles exposure, could be a sensitive and reliable tool for discriminating human exposure to Anopheles bites in area of low and seasonal malaria transmission., Methods: A multi-disciplinary survey was performed in Northern Senegal where An. gambiae s.l. is the main malaria vector. Human IgG Ab response to gSG6-P1 salivary peptide was compared according to the season and villages in children from five villages in the middle Senegal River valley, known as a low malaria transmission area., Results: IgG levels to gSG6-P1 varied considerably according to the villages, discriminating the heterogeneity of Anopheles exposure between villages. Significant increase of IgG levels to gSG6-P1 was observed during the peak of exposure to Anopheles bites, and decreased immediately after the end of the exposure season. In addition, differences in the season-dependent specific IgG levels between villages were observed after the implementation of Long-Lasting Insecticidal Nets by The National Malaria Control Program in this area., Conclusion: The gSG6-P1 salivary peptide seems to be a reliable tool to discriminate the micro-geographical heterogeneity of human exposure to Anopheles bites in areas of very low and seasonal malaria transmission. A biomarker such as this could also be used to monitor and evaluate the possible heterogeneous effectiveness of operational vector control programs in low-exposure areas.

Diffuse systemic sclerosis carries a high morbidity and mortality. The Prospective Registry of Early Systemic Sclerosis (PRESS), a multicentre incident cohort study of patients with early diffuse cutaneous systemic sclerosis, has the goal of advancing the understanding of disease pathogenesis and identifying novel biomarkers. In this review, PRESS investigators discuss the evidence pertaining to the more commonly used treatments for early diffuse SSc skin disease including methotrexate, mycophenolate, cyclophosphamide, azathioprine, and intravenous immunoglobulin. This review highlights the unmet need for effective treatment in early diffuse SSc as well as its more rigorous study. Nonetheless, the PRESS investigators aim to decrease intra- and inter-institutional variability in prescribing in order to improve the understanding of the clinical course of early diffuse SSc skin disease.

We describe a new species of myxozoan, Henneguya mauritaniensis n. sp., extracted from the arterial bulb of the bluespotted seabream, Pagrus caeruleostictus (Valenciennes, 1830), collected in Mauritanian waters. Out of the 209 individuals examined, 30.1 % were infected with this new taxon. Spore total length ranged from 15.0 to 20.5 μm with a mean of 17.9 μm. The two polar capsules were equal in size, and pyriform and caudal appendages joined until mid-length. Morphometric analysis revealed significant differences between H. mauritaniensis n. sp. and morphologically similar species from this region as well as congeners known from other sparid hosts. Phylogenetic analysis of 18 S rDNA indicated that this new species is closely related to Henneguya pagri, reported recently from Pagrus major off Japan. Bayesian inference and maximum likelihood analyses of the 18 S rDNA dataset also revealed that species of marine Henneguya reported forming pseudocysts in the hearts of their fish hosts were closely related. Histological analysis of the H. mauritaniensis n. sp. pseudocysts embedded in the arterial bulb of P. caeruleostictus suggests that these parasites may cause considerable pathology, which may impact negatively on the health of the fish host. Finally, we discussed the importance of a combination of morphological and molecular analysis for species description because of high variability in size within the same taxa.

Previous studies have shown that the transforming growth factor (TGF)β/Alk1/Smad1 signaling pathway is constitutively activated in a subset of systemic sclerosis (SSc) fibroblasts and this pathway is a critical regulator of CCN2 gene expression. Caveolin-1 (cav-1), an integral membrane protein and the main component of caveolae, has also been implicated in SSc pathogenesis. This study was undertaken to evaluate the role of caveolin-1 in Smad1 signaling and CCN2 expression in healthy and SSc dermal fibroblasts. We show that a significant subset of SSc dermal fibroblasts has up-regulated cav-1 expression in vitro, and that cav-1 up-regulation correlates with constitutive Smad1 phosphorylation. In addition, basal levels of phospho-Smad1 were down-regulated after inhibition of cav-1 in SSc dermal fibroblasts. Caveolin-1 formed a protein complex with Alk1 in dermal fibroblasts, and this association was enhanced by TGFβ. By using siRNA against cav-1 and adenoviral cav-1 overexpression we demonstrate that activation of Smad1 in response to TGFβ requires cav-1 and that cav-1 is sufficient for Smad-1 phosphorylation. We also show that cav-1 is a positive regulator of CCN2 gene expression, and that it is required for the basal and TGFβ-induced CCN2 levels. In conclusion, this study has revealed an important role of cav-1 in mediating TGFβ/Smad1 signaling and CCN2 gene expression in healthy and SSc dermal fibroblasts., (© 2012 The Authors Journal of Cellular and Molecular Medicine © 2012 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.)

Unlabelled: In patients with renal failure, iodinated contrast agents may cause acute deterioration of the renal function and gadolinium-based contrast agents (GBCAs) may cause nephrogenic systemic fibrosis (NSF). The administration of a contrast agent must thus be reviewed for each patient and evaluation of renal function is paramount even though its estimation using formulas derived from the creatinine level may fluctuate. For iodinated contrast agents, contrast induced nephropathy is reduced by hydratation, preferably intravenous, when the GFR is less than 60 ml/min. The risk for intravenous injections is less than the risk for arterial injections, and the GFR threshold may be reduced to 45 ml/min. For gadolinium-based contrast agents, patients at risk for NSF are those with end-stage renal disease and patients undergoing dialysis. In such cases, the injection of a gadolinium-based contrast agent is only considered after a risk-benefit analysis has been completed, an alternate linear or macrocyclic agent issued and the dose limited to 0,1 mmol Gd/kg. Recently, recommendations from US and European agencies have converged., Learning Objectives: to be familiar with the risk factors of CIN with iodinated contrast agents; to be familiar with hydration procedures for patients at risk of CIN; to be familiar with the diagnostic criteria of NSF; to be familiar with the classification of GBCA with regards to the risk of NSF; to be familiar with the contraindications of the different groups of GBCA., (Copyright © 2011. Published by Elsevier Masson SAS.)

This article reviews the clinical background and significance of selected biomarkers that have been studied in relation to systemic sclerosis, or scleroderma, a devastating connective tissue disease whose morbidity and mortality are often related to pulmonary complications. Interstitial lung disease is the most common pulmonary manifestation in systemic sclerosis, and the search for a noninvasive biomarker to assess and monitor patients and their lung disease is a nascent and expending field of study. In this article, we examine the background and significance of a variety of selected biomarkers and assess their role in relation to systemic sclerosis–related interstitial lung disease.

Objectives: This retrospective study was carried out to describe the epidemiological, clinical and aetiological profile of parasitic and fungal neuroinfections at the Infectious Diseases Clinic in Fann Teaching Hospital in Dakar., Patients and Methods: Data were collected for analysis from patients files recorded from January 1, 2001 to December 31, 2003., Results: We found 126 cases of parasitic and fungal neuroinfections, representing 62% of the total of neuroinfections cases (126/203) and 27% of cerebro-meningeal diseases encountered at the clinic during the study period (126/470). Sex ratio M/F was 1.7 and the mean age of patients was 32 years +/- 14.4. Thirty seven patients (30%) were HIV seropositive. Aetiologies were represented by cerebral malaria (85 cases), neuromeningeal cryptococcosis (37 cases) and toxoplasmosis (4 cases). The overall case fatality rate was 38% (48 deaths/126). The fatality rate varied according to aetiologies: 27% in cerebral malaria, and 59.5% in neuromeningeal cryptococcosis that was found mainly among HIV positive patients (34 cases/37)., Conclusion: These results give evidence of the frequency and the gravity of the adult's cerebral malaria in Dakar, but also the growing place of the neuromeningeal cryptococcosis in the neuromeningeal opportunist pathology of HIV positive patients.

Purpose: To assess placental perfusion and permeability in mice with magnetic resonance (MR) imaging., Materials and Methods: This study was conducted according to French law and National Institutes of Health recommendations for animal care. Twenty-two pregnant BALB/c mice were examined at 1.5 T with a single-section dual-echo fast spoiled gradient-echo sequence. Two injection protocols were used: monophasic injection (double the clinical dose of contrast agent) and biphasic injection (quadruple the clinical dose). Signal intensities (SIs) were measured in the maternal left ventricle, placenta, and fetus (n = 16). At these high gadolinium doses, a T2* effect correction was used. SIs were converted to gadolinium concentrations and were analyzed by using a three-compartment model. Quantitative microcirculation parameters were calculated. Results with the monophasic and biphasic protocols were compared, and final arterial concentrations determined with MR imaging were compared with those determined with atomic emission spectrophotometry by using the unpaired Student t test., Results: Perfusion and permeability parameters for monophasic and biphasic injections were similar: Mean placental blood flow was 180 mL/min/100 g, mean permeability surface coefficient from maternal placental to fetal placental compartment was 10.3 x 10(-4) sec(-1) +/- 6.81 (standard deviation), mean permeability surface coefficient from fetal placental to maternal placental compartment was 4.65 x 10(-4) sec(-1) +/- 4.37, and mean fractional volume of the maternal vascular placental compartment was 36.5% +/- 0.9. Placental (146 vs 105 micromol/L, P < .004) and fetal (33.3 vs 19.1 micromol/L, P < .001) gadolinium concentrations were higher with the biphasic than with the monophasic protocol. Arterial gadolinium concentrations at MR imaging did not differ significantly from those at spectrophotometry for the monophasic (P = .254) or biphasic (P = .776) injection protocol., Conclusion: Placental perfusion and permeability can be measured in vivo by using high gadolinium doses and a dual-echo MR imaging sequence., ((c) RSNA, 2006.)

Lithiasis is the most common disease of salivary glands after mumps. The purpose of this review is to analyze the respective role of the different available imaging techniques for the diagnosis of lithiasis and related complications since the treatment of salivary lithiasis has evolved with the emergence of minimally invasive and non surgical techniques. In spite of its limitations, US represents an excellent first line imaging technique because it is non-invasive and widely available. Non contrast helical CT with multiplanar reconstructions seems to be the gold standard for the diagnosis of lithiasis, especially when small and poorly calcified since these may not be visible on standard radiographs. CT allows accurate characterization of the number and position of lithiasis. MR Sialography is increasingly replacing the more invasive conventional sialography for the non invasive visualization of the ductal system of major salivary glands even though conventional sialography has a higher spatial resolution.

This retrospective study was carried out to describe the epidemiological, clinical and aetiological aspects of clear-fluid meningitis among HIV-positive patients admitted at the Infectious Diseases Clinic in Fann Teaching Hospital in Dakar Data were collected for analysis from patients files recorded from January 1, 2001 to December 31, 2003. Forty-six cases of clear-fluid meningitis were found among HIV-infected patients, representing 51.7% of cerebro-meningeal diseases and 92% of meningitis encountered in those patients. Sex ratio MIF was 1.5 and the mean age of patients was 40.7 years [range 23-61 years]. Clinical presentations comprised headache (80%), fever (67%), meningeal syndrome (74%), coma (28%), convulsions (9%), focal neurological deficits (11%), cranial nerves dysfunction (9%). Aetiologies were represented by neuromeningeal cryptococcosis (29 cases) and tuberculous meningitis (5 cases). In 26% of cases no aetiology was found. The case fatality rate was 63% overall (29 deaths) and 83.3% among cases with unknown aetiology. It did not vary significantly according to epidemiological and clinical variables studied. Neurological sequelae were found in 4 patients who recovered. A better management of clear-fluid meningitis among HIV-positive patients should benefit from the reinforcement of our diagnostic capacities, the availability of effective systemic antifungal drugs and the prevention of opportunistic infections in the course of HIV/AIDS infection.

Objective: Burned-out tumors of the testis are extremely rare. From 5 new cases, the clinical and radiologic findings are discussed in light of a review of the literature., Methods: Over a 13-year period, 5 patients 17 to 50 years old were admitted with metastatic germ cell neoplasms. All were explored by thoracic and abdominal computed tomography and scrotal sonographic examination., Results: The disease was revealed by the presence of lymphadenopathies in 4 of these patients: retroperitoneal in 3 and supraclavicular in the other. Scrotal sonography revealed abnormalities in all cases., Conclusions: Burned-out tumors may cause some confusion in the diagnosis, because secondary tumors can often be mistaken for primary tumors. Careful evaluation of the testis is crucial for identifying the primary lesion site; all abnormalities shown on clinical or sonographic scrotal examination call for orchidectomy.

Unicapsula marquesi n. sp. (Myxosporea) is described from gill filaments of Polydactylus quadrifilis (Pisces, Polynemidae) obtained from coats of Senegal. The cysts were elongated and their length was 1 to 3 mm. The spores were pyramidal and composed of three valves. Only one of theses valves contained a developed polar capsule measuring 3.01 +/- 0.09 microns in diameter. Length of spore was 6.13 +/- 0.21 microns and the width was 7.18 +/- 0.17. No filament like appendage at the extremity of shell valves. Data on ultrastructure of spores are presented.

We present our treatment strategy for distal radius fractures, based on intrafocal pinning (Kapandji) and further combination with a palmar plate resulting in bowl osteosynthesis (Nonnenmacher). Even with a changing surgical team, we got more than 80% good results and rapid revalidation. We thus favor dynamic minimal osteosynthesis close to the fracture physiopathology. Indication for external fixation becomes limited to open or comminutive fractures.

Microfilum lutjani n. g., n. sp. (Microsporida) was found on the gill filaments of Lutjanus fulgens (Teleost) inhabiting the coasts of Senegal. This microsporidium forms xenomas distinguished by the microvilli covering the plasma membrane. At all stages of development individuals have isolated nuclei and are in direct contact with the host cytoplasm. Merogony is binary and sporogony is tetrasporoblastic. The spore (4.75 x 2.60 microns) is characterized by a manubrium inserted on a laterally offset anchoring disc and extending into a very short, noncoiled polar filament (no longer than 500 nm) in the form of a hook. This type of polar filament has not been described previously in the Microsporida.