Search

Ebolavirus and Marburgvirus, two filoviruses belonging to the Filoviridae family, are among the most virulent pathogens for humans and non-human primates, causing outbreaks of fulminant hemorrhagic fever (HF) in Central African countries with case fatality rates of up to 90%. Fruit bats are the likely reservoir, and human infection occurs through contact with bats or infected large-animal carcasses or by person-to-person contact (through body fluids, medical care, and burial practices). Schematically, clinical manifestations occur in three successive phases and include general, gastrointestinal, and mucocutaneous disorders. Death usually results from hemorrhagic complications. Cutaneous manifestations rarely make a major contribution to disease severity but can assist with the diagnosis. Rash, the main cutaneous disorder, is nonspecific and cannot guide the differential diagnosis. Immunohistochemical examination of skin biopsy or necropsy specimens can confirm the diagnosis., (© 2012 The International Society of Dermatology.)

Introduction: In literature, many controversies exist about courses and terminology of the distal medial striate artery (DMSA) or recurrent artery first described by Heubner near 1872. The purpose of this study was to define the accurate anatomy of this artery, to help the practitioners during surgery of the anterior cerebral-anterior communicating arteries (ACA-ACoA) complex., Materials and Methods: 20 cranial bases were examined using magnification of the surgical microscope. One half for which the internal carotid arteries and internal jugular veins were dissected, cannulated and perfused with colored silicon on fresh cadavers; the other half only with arterial injection of formalin-fixed normal adult human brains., Results: The artery arose principally from A2 segment (58%), always less than 5 mm up to downstream from ACA to ACoA junction. In 59.5% it had a recurrent course anterior to A1 segment. It terminated in one to three stems which entered the medial part of the anterior perforated substance. The DMSA was present as a single vessel in 95% of cases. Its main outer diameter was 0.7 mm and the length had an average of 24 mm., Conclusion: Iatrogenic damage or occlusion leads to a mediobasal striatum infarction with important neurological deficits such as brachiofacial hemiparesis and aphasia. This artery should be routinely identified during clipping of ACoA aneurysm. Special attention in this study was given to atypical posterior course or anatomic variations such as double DMSA on a same side.

Background: The polymerase chain reaction (PCR) has been proposed for diagnosis, staging and post-treatment follow-up of sleeping sickness but no large-scale clinical evaluations of its diagnostic accuracy have taken place yet., Methodology/principal Findings: An 18S ribosomal RNA gene targeting PCR was performed on blood and cerebrospinal fluid (CSF) of 360 T. brucei gambiense sleeping sickness patients and on blood of 129 endemic controls from the Democratic Republic of Congo. Sensitivity and specificity (with 95% confidence intervals) of PCR for diagnosis, disease staging and treatment failure over 2 years follow-up post-treatment were determined. Reference standard tests were trypanosome detection for diagnosis and trypanosome detection and/or increased white blood cell concentration in CSF for staging and detection of treatment failure. PCR on blood showed a sensitivity of 88.4% (84.4-92.5%) and a specificity of 99.2% (97.7-100%) for diagnosis, while for disease staging the sensitivity and specificity of PCR on cerebrospinal fluid were 88.4% (84.8-91.9%) and 82.9% (71.2-94.6%), respectively. During follow-up after treatment, PCR on blood had low sensitivity to detect treatment failure. In cerebrospinal fluid, PCR positivity vanished slowly and was observed until the end of the 2 year follow-up in around 20% of successfully treated patients., Conclusions/significance: For T.b. gambiense sleeping sickness diagnosis and staging, PCR performed better than, or similar to, the current parasite detection techniques but it cannot be used for post-treatment follow-up. Continued PCR positivity in one out of five cured patients points to persistence of living or dead parasites or their DNA after successful treatment and may necessitate the revision of some paradigms about the pathophysiology of sleeping sickness.

Spreading of urban wastewater on agricultural land may lead to concomitant input of organic and inorganic pollutants. Such multiple pollution sites offer unique opportunities to study the fate of both heavy metals and pharmaceuticals. We examined the occurrence and fate of selected antibiotics in sandy-textured soils, sampled four years after cessation of 100 years irrigation with urban wastewater from the Paris agglomeration. Previous studies on heavy metal contamination of these soils guided our sampling strategy. Six antibiotics were studied, including quinolones, with a strong affinity for organic and mineral soil components, and sulfonamides, a group of more mobile molecules. Bulk samples were collected from surface horizons in different irrigation fields, but also in subsurface horizons in two selected profiles. In surface horizons, three quinolones (oxolinic acid, nalidixic acid, and flumequine) were present in eight samples out of nine. Their contents varied spatially, but were well-correlated one to another. Their distributions showed great similarities regarding spatial distribution of total organic carbon and heavy metal contents, consistent with a common origin by wastewater irrigation. Highest concentrations were observed for sampling sites close to irrigation water outlets, reaching 22 μg kg(-1) for nalidixic acid. Within soil profiles, the two antibiotic groups demonstrated an opposite behavior: quinolones, found only in surface horizons; sulfamethoxazole, detected in clay-rich subsurface horizons, concomitant with Zn accumulation. Such distribution patterns are consistent with chemical adsorption properties of the two antibiotic groups: immobilization of quinolones in the surface horizons ascribed to strong affinity for organic matter (OM), migration of sulfamethoxazole due to a lower affinity for OM and its interception and retention in electronegative charged clay-rich horizons. Our work suggests that antibiotics may represent a durable contamination of soils, and risks for groundwater contamination, depending on the physicochemical characteristics both of the organic molecules and of soil constituents., (Copyright © 2010 Elsevier B.V. All rights reserved.)

BACKGROUND. Clinical management of human African trypanosomiasis requires patient follow-up of 2 years' duration. At each follow-up visit, cerebrospinal fluid (CSF) is examined for trypanosomes and white blood cells (WBCs). Shortening follow-up would improve patient comfort and facilitate control of human African trypanosomiasis. METHODS. A prospective study of 360 patients was performed in the Democratic Republic of the Congo. The primary outcomes of the study were cure, relapse, and death. The WBC count, immunoglobulin M level, and specific antibody levels in CSF samples were evaluated to detect treatment failure. The sensitivity and specificity of shortened follow-up algorithms were calculated. RESULTS. The treatment failure rate was 37%. Trypanosomes, a WBC count of > or = 100 cells/microL, and a LATEX/immunoglobulin M titer of 1:16 in CSF before treatment were risk factors for treatment failure, whereas human immunodeficiency virus infection status was not a risk factor. The following algorithm, which had 97.8% specificity and 94.4% sensitivity, is proposed for shortening the duration of follow-up: at 6 months, patients with trypanosomes or a WBC count of > or = 50 cells/microL in CSF are considered to have treatment failure, whereas patients with a CSF WBC count of > or = 5 cells/microL are considered to be cured and can discontinue follow-up. At 12 months, the remaining patients (those with a WBC count of > or = 6-49 cells/microL) need a test of cure, based on trypanosome presence and WBC count, applying a cutoff value of > or = 20 cells/microL. CONCLUSION. Combining criteria for failure and cure allows follow-up of patients with second-stage human African trypanosomiasis to be shortened to a maximum duration of 12 months.

This study concerns the treatment by precipitation of three acidic and metal-rich leachates by using various reagents. Two treatment modes (simple and combined precipitation) have been performed to evaluate the metals removal efficiency and the dewatering ability of the generated sludge. It appears that for the three leachates used, the Ca(OH)(2) addition gave better metals removal at pH 10.0 than the use of NaOH at the same pH. Moreover, the combination of NaOH and Na(2)S allows better removal for Pb(2+), Zn(2+), Cu(2+) and Mn(2+) ions than with NaOH/Na(2)CO(3) or NaOH/Na(2)HPO(4). The dewaterability (vacuum filtration) of precipitates produced during the treatment of soil leachate was established as follows on the basis of the specific resistance to filtration (SRF) values: sulphides (4.3 x 10(12)mkg(-1))

Background: Human African trypanosomiasis (HAT; sleeping sickness) caused by Trypanosoma brucei gambiense is a fatal disease. Current treatment options for patients with second-stage disease are toxic, ineffective, or impractical. We assessed the efficacy and safety of nifurtimox-eflornithine combination therapy (NECT) for second-stage disease compared with the standard eflornithine regimen., Methods: A multicentre, randomised, open-label, active control, phase III, non-inferiority trial was done at four HAT treatment centres in the Republic of the Congo and the Democratic Republic of the Congo. Patients aged 15 years or older with confirmed second-stage T b gambiense infection were randomly assigned by computer-generated randomisation sequence to receive intravenous eflornithine (400 mg/kg per day, every 6 h; n=144) for 14 days or intravenous eflornithine (400 mg/kg per day, every 12 h) for 7 days with oral nifurtimox (15 mg/kg per day, every 8 h) for 10 days (NECT; n=143). The primary endpoint was cure (defined as absence of trypanosomes in body fluids and a leucocyte count

Chemical leaching of the toxic metals (cadmium, chromium, copper, nickel, lead, and zinc) and behavior of other elements (aluminum, calcium, iron, potassium, magnesium, manganese, sodium, phosphorus, and sulfur) in the wastewater sludge of the Montreal Urban Community wastewater treatment plant (Montreal, Quebec, Canada) were studied in 2-L beakers using sulfuric acid and three oxidants [H2O2, FeCl3, and Fe2(SO4)3] and their association. Metal removal efficiencies of these oxidants were evaluated under different conditions of pH (2.0 and 2.5) and oxidation-reduction potential (ORP) (350 to 500 mV). The solubilization of the different elements was linked to pH and/or ORP, and a period of 2 to 4 hours was required to obtain satisfactory metals removal yields. Sludge-fertilizing properties generally were little affected by the decontamination process, especially for processes using a ferric salt. Finally, optimal conditions, for best metals solubilization, were established at pH 2.5 and ORP = 450 mV in a 4-hour period.

ATP-dependent proteases are processive, meaning that they degrade full-length proteins into small peptide products without releasing large intermediates along the reaction pathway. In the case of the bacterial ATP-dependent protease ClpAP, ATP hydrolysis by the ClpA component has been proposed to be required for processive proteolysis of full-length protein substrates. We present here data showing that in the absence of the ATPase subunit ClpA, the protease subunit ClpP can degrade full-length protein substrates processively, albeit at a greatly reduced rate. Moreover, the size distribution of peptide products from a ClpP-catalyzed digest is remarkably similar to the size distribution of products from a ClpAP-catalyzed digest. The ClpAP- and ClpP-generated peptide product size distributions are fitted well by a sum of multiple underlying Gaussian peaks with means at integral multiples of approximately 900 Da (7-8 amino acids). Our results are consistent with a mechanism in which ClpP controls product sizes by alternating between translocation in steps of 7-8 (+/-2-3) amino acid residues and proteolysis. On the structural and molecular level, the step size may be controlled by the spacing between the ClpP active sites, and processivity may be achieved by coupling peptide bond hydrolysis to the binding and release of substrate and products in the protease chamber.

Assessment of the purity of chromatographic peaks is an important step in developing and validating purification procedures for complex mixtures. While curve-fitting techniques can be useful for determining the retention times and relative concentrations of the components of a chromatographic peak, their utility is limited by the lack of unambiguous criteria for determining the number of such components. In this work, we present a computational technique for analyzing chromatograms to estimate the number of components, their retention times, and their relative concentrations. In contrast to Fourier-transform-based techniques, the technique we present does not require manual peak identification. It is based on curve-fitting and uses the Akaike information criterion to estimate the number of components. Application of the technique to chromatograms obtained from size-exclusion and reverse-phase chromatography of test mixtures indicates that it is useful for the characterization of complex mixtures.

Disc method is used as a preliminary qualitative test, in order to check the mycobacterial susceptibility to sulfadiazine and cotrimoxazole, while the percentage method gives a quantitative antibiogram in testing with precision the microbial susceptibility to sulfadiazine, sulfamethoxazole, sulfamethoxydiazine, sulfadimethoxine and cotrimoxazole. Both methods are performed in tube, on Löwenstein-Jensen medium. The mycobacteria tested include 114 strains representing 10 species. The results show that sulfonamides and cotrimoxazole exert an inhibitory power which can vary according to the species : it is excellent for M. fortuitum, M. kansasii, M. marinum, M. scrofulaceum, M. szulgai and M. xenopi, weaker for M. ulcerans, mediocre for M. avium and M. tuberculosis, non existent for M. bovis. The percentage method shows that the MIC is less with cotrimoxazole and sulfamethoxazole than with other sulfonamides. Within the same species as M. avium, there are marked differences of bacterial susceptibility to these antibacillaries, according to the strains.

Disc method checks the bacterial susceptibility to erythromycin, tetracycline and cotrimoxazole, while the percentage method determines the MIC and the proportion of resistant bacilli at a critical concentration. The mycobacteria include 113 strains representing 12 species. Both methods show that cotrimoxazole is more active on germs than the other substances. Nevertheless, the sensitivity varies with the species, according to the technique. As the proportion method is a more reliable test to establish the susceptibility of mycobacteria, we have only used this technique to determine the activity spectrum of the various drugs. Specifically, M. marinum, M. scrofulaceum and M. szulgai are inhibited by the three substances, while M. kansasii, M. ulcerans and M. xenopi are especially sensitive to cotrimoxazole and erythromycin. M. fortuitum and M. haemophilum are particularly sensitive to cotrimoxazole, while they are resistant to erythromycin and tetracycline. It is the contrary with M. chelonei. M. avium and M. tuberculosis are sensitive to erythromycin and cotrimoxazole, but to a lower degree, while M. bovis does not respond to any drugs.