Coagulase negative staphylococci in Anti-Cancer Center, Batna, Algeria: antibiotic resistance pattern, biofilm formation, and detection of mecA and icaAD genes

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Sequence crystallization during isotherm evaporation of southern Algeria chott Baghdad natural brine

Southern Algerian's natural brine sampled from chott Baghdad may be a source of mineral salts with a high economic value. These salts are recoverable by simple solar evaporation. Indeed, during isothermal solar evaporation, it is possible to recover mineral salts and to determine the precipitation sequences of different salts as a function of the chemical composition and the density of the brine. In this study, the variation of ionic composition of concentrated brine during isothermal evaporation was measured; then the experimental pathway of the point representing its composition on the oceanic fivefold diagram Na+, K+, Mg2+, Cl-, SO4 2-//H2O was plotted. In order to follow the precipitation sequences of mineral salts, during solar evaporation at 35°C, X-Ray diffraction was performed on the precipitated and removed salts from the brine during evaporation.Keywords: seawater quinary diagram, Jänecke projection, isothermal evaporation, mineral salts, chott Baghdad brin

Klebsiella pneumoniae producing extended spectrum β-lactamase in Regional Military University Hospital of Oran, Algeria: antibiotic resistance, biofilm formation, and detection of blaCTX-M and blaTEM genes

Background: Klebsiella pneumoniae is a bacterial pathogen commonly associated with severe nosocomial and community acquired infections  especially through the acquisition of extended spectrum β-lactamases (ESβL) and biofilm formation capacity. The objectives of this study are to determine the prevalence of K. pneumoniae ESβL (KP-ESβL)-producing isolates in the Regional Military University Hospital of Oran (HMRUO) Algeria,characterize their antibiotic resistance profile, genetically detect blaTEM and blaCTX-M genes, and evaluate their biofilm formation capacity.Methodology: Different clinical specimens including blood, cerebrospinal fluids, urine and catheter, pus, perirectal abscess, and surgical wounds were collected from patients with suspected clinical infections in different units and departments of the hospital. The specimens were cultured on Blood, MacConkey and CLED agar (for urine only) plates and incubated aerobically for 24 hours at 37°C for preliminary identification of bacteria using conventional colony morphology, Gram stain reaction, and disk diffusion test for antibiotic susceptibility testing (AST). Confirmation of isolates, antibiogram, minimum inhibitory concentration (MIC) and detection of resistance phenotypes, were carried out by the automated Vitek 2 (BioMérieux) identification and susceptibility method. ESβL production was confirmed by the synergy and combination disk tests. ESβL genes were detected by conventional simplex PCR and biofilm formation was detected by the tissue culture plate (TCP) method.Results: A total of 630 patients’ clinical samples (one sample per patient) were processed. Klebsiella pneumoniae was isolated in 40 (6.3%) samples, and 15 of these (37.5%) produced ESβL. In the disk diffusion AST assay, all 40 K. pneumoniae isolates were resistant to ampicillin and ticarcillin while all 40 isolates were sensitive to cefoxitin, imipenem and ertapenem. KP-ESβL producing isolates were more frequently recovered from intensive care unit (33.3%) and from urine (46.7%) samples. Group 1 blaCTX-M genes were detected in 13 of the 15 (86.7%) KP-ESβL isolates, and 46.7% of these isolates were moderate biofilm producers.Conclusion: There is need for health departments to put in place preventative measures through regular surveillance of these resistant pathogens and initiating appropriate infection prevention and control strategies to limit their spread in Algerian hospitals and worldwide. Keywords: Klebsiella pneumoniae, ESβL, biofilm, PCR, antibacterial resistance   French title: Klebsiella pneumoniae productrice de-lactamase spectre tendu dans l'hôpital universitaire militaire régional d'Oran, Algérie: résistance aux antibiotiques, formation de biofilm et détection desgènes blaCTX-M et blaTEM Contexte: Klebsiella pneumoniae est un pathogène bactérien communément associé aux infectionsnosocomiales et communautaires sévères, en particulier par l'acquisition de β-lactamases à spectre étendu(ESβL) et la capacité de formation de biofilm. Les objectifs de cette étude sont de déterminer la prévalence desisolats de K. pneumoniae producteurs de βLSE (KP-βLSE) au CHU d'Oran (HMRUO) Algérie, caractériser leurprofil de résistance aux antibiotiques, détecter génétiquement les gènes blaTEM et blaCTX-M, et évaluer leurcapacité de formation de biofilm.Méthodologie: Différents échantillons cliniques, y compris du sang, des liquides céphalo-rachidiens, de l'urinemictionnelle et du cathéter, du pus, des abcès périrectal et des plaies chirurgicales ont été prélevés despatients suspectés d'infections cliniques dans différentes unités et départements de l'hôpital. Les échantillonsont été cultivés sur des milieu de culture: deglose au sang, MacConkey et CLED (pour l'urine uniquement) etincubés en aérobie pendant 24heures à 37°C pour l'identification préliminaire des bactéries en utilisant lamorphologie conventionnelle des colonies, la coloration de Gram et le test de diffusion sur disque pour les testsde sensibilité aux antibiotiques (AST). La confirmation des isolats, l'antibiogramme, la concentration minimaleinhibitrice (CMI) et la détection des phénotypes de résistance ont été réalisés par la méthode automatiséed'identification et de sensibilité sur Vitek 2 (BioMérieux). La production de βLSE a été confirmée par les tests desynergie et de double disques. Les gènes de βLSE ont été détectés par PCR simplex conventionnelle et laformation de biofilm a été détectée par la méthode de la plaque de culture tissulaire (TCP).Résultats: Un total de 630 échantillons cliniques de patients (un échantillon par patient) ont été traités.Klebsiella pneumoniae a été isolé dans 40 échantillons (6,3%) et 15 d'entre eux (37,5%) ont produit des βLSE.Dans le test AST à diffusion sur disque, tous les 40 isolats de K. pneumoniae étaient résistants à l'ampicilline età la ticarcilline, tandis que les 40 isolats étaient sensibles à la céfoxitine, à l'imipénème et à l'ertapénème. Lesisolats producteurs de KP-βLSE ont été plus fréquemment récupérés dans les unités de soins intensifs (33,3%)et dans les échantillons d'urine (46,7%). Les gènes blaCTX-M du groupe 1 ont été détectés dans 13 des 15 isolatsde KP-βLSE (86,7%), et 46,7% de ces isolats étaient des producteurs de biofilm modérés.Conclusion: Il est nécessaire que les services de santé mettent en place des mesures préventives grâce à unesurveillance régulière de ces pathogènes résistants et à la mise en place de stratégies appropriées deprévention et de contrôle des infections pour limiter leur propagation dans les hôpitaux algériens et dans lemonde. Mots clés: Klebsiella pneumoniae, βLSE, biofilm, PCR, résistance antibactérienne &nbsp

Inuloxin E, a New Seco-Eudesmanolide Isolated from Dittrichia viscosa, Stimulating Orobanche cumana Seed Germination

A new sesquiterpenoid belonging to the subgroup seco-eudesmanolides and named inuloxin E was isolated from Dittrichia viscosa, together with the already known sesquiterpenoids inuloxins A–D and -costic acid. Inuloxin E was characterized by spectroscopic data (essentially NMR and ESIMS) as 3-methylene-6-(1-methyl-4-oxo-pentyl)-3a,4,7,7a-tetrahydro-3H-benzofuran-2-one. Its relative configuration was determined by comparison with the closely related inuloxin D and chemical conversion of inuloxin E into inuloxin D and by the observed significant correlation in the NOESY spectrum. Both inuloxins D and E induced germination of the parasitic weed Orobanche cumana, but were inactive on the seeds of Orobanche minor and Phelipanche ramosa. The germination activity of some hemisynthetic esters of inuloxin D was also investigated

Chemical composition analysis of essential oils of four plants from Aurès region of Algeria and their antibacterial and antibiofilm activities against coagulase-negative staphylococci

Background: The altitudinal and geographical variability of the Aurès mountains of Algeria favored the existence of some endemic and rare varieties of medicinal plants. The aim of the present work is to determine the chemical composition, antimicrobial and antibiofilm properties of the  essential oils (EOs) from aerial parts of four medicinal plants from Aurès region of Algeria; Juniperus thurifera L., Juniperus oxycedrus L., Salvia   officinalis L. and Thymus ciliatus ssp. munbyanus (Boiss. & Reut.) Batt. on coagulase negative staphylococci (CoNS) isolates. Methodology: Extraction of EOs from the four plant materials was carried out by hydro-distillation, and the EO yield expressed in gram of the distillate per 100 grams of dry matter. The chemical composition of the EOs was analyzed by gas chromatography-mass spectrometry (GC-MS) method. In vitro antibacterial and antibiofilm activities of the EOs were evaluated against CoNS previously isolated at the Anti-Cancer Center of Batna, Algeria using the agar disc diffusion assay and biofilm inhibition study, respectively. Minimum inhibitory concentration (MIC) and minimum  bacterial concentration (MBC) of the EOs of S. officinalis L. and T. ciliatus ssp. munbyanus were determined by the dilution method. Results: Twenty-seven and 41 compounds rich in monoterpene hydrocarbons were identified from J. oxycedrus and J. thurifera plants respectively, while 45 and 32 compounds, constituted mainly by oxygenated monoterpenes, were identified from S. officinalis L. and T. ciliatus ssp. munbyanus, respectively. The EOs of T. ciliatus ssp. munbyanus showed the most inhibitory activity of all the four plants on CoNS isolates (n=66) with mean  inhibition zone diameter of 24.99±6.29mm, and mean MIC and MBC values of 2.65±3.77mg/ml and 5.31±7.41mg/ml respectively, followed by S.  officinalis L., with mean inhibition zone diameter of 13.38± 6.52mm, and mean MIC and MBC values of 27.53±28.2 mg/ml and 31.97±33.19 mg/ml  respectively (p<0.0001 by one-way ANOVA). Also, percentage biofilm inhibition of CoNS isolates (n=59) was high for EOs of T. ciliatus ssp. munbyanus  (65.63±10.71%) and S. officinalis L. (53.13±5.83%), although was significantly higher for T. ciliatus ssp. munbyanus compared to S. officinalis L. (p<0.0001, t=7.874). Conclusion: Essential oils from T. ciliatus ssp. munbyanus and S. officinalis L. could represent an alternative to classical antibiotics against planktonic cells and biofilms of CoNS

A New Method of Timing Estimation for OFDM Systems

A new algorithm for the timing offset estimation for Orthogonal Frequency Division Multiplexing (OFDM) system is presented. The proposed algorithm solves the uncertainty due to the plateau in Schmidl and Cox method. Also the new algorithm can be applied to any system that uses a preamble with two identical half with or without cyclic prefix. It has a better precision than previous proposed algorithms expressed in terms of mean and variance of the estimation error even in highly dispersive channels

Saharan lithium: Brine chemistry of chotts from eastern Algeria

Salt pan brines in desert areas are globally known to be rich sources of lithium. This study reports the results of a regional survey of brine chemistry in chotts (salt pans) conducted along a 550 km long valley in the northeast Algerian Sahara, one of the major desert areas on Earth. A dataset composed of 50 samples, including brine, river, and aquifer, is integrated and discussed in order to study the characteristics of Sahara brines. Brines contain up to 66 mg L−1 of lithium, salinities up to ~400 g L−1, and magnesium concentrations ~690 times greater than that of lithium. The primary source of major ions would occurr by dissolution of ancient evaporites of the substrate by aquifer waters. Near surface lithium concentration of brines in chotts across the study area and in the aquifer Complexe Terminal defines a pattern of increasing values to the north, where maximum values coincide with chotts (Melghir and Merouane) having the largest sizes (up to 1,840 km2) and placed at the lowest altitudes (36 m below sea level). This pattern coincides with the northwards plunging structured substrate. Lithium grades increase consistently with salinity during the concentration through evaporation. However, lithium continues to concentrate beyond evolved brines whether due to the precipitation of lithium-free salts leading to lithium increases in residual brine, and/or by unknown processes supplying additional lithium. Discussed aspects are expected to drive an increasing interest on chotts, which would reveal in the future, as a stimulating opportunity for Algeria and the Saharan region.Fil: Zatout, Merzouk. University Kasdi Merbah - Ouargla. ; ArgeliaFil: López Steinmetz, Romina Lucrecia. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Hacini, Messaoud. University Kasdi Merbah - Ouargla.; ArgeliaFil: Fong, Shao Bing. University of Melbourne; AustraliaFil: M'nif, Adel. University Of Carthage; TúnezFil: Hamzaoui, A. H.. University Of Carthage; TúnezFil: López Steinmetz, Lorena Cecilia. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; Argentin