Co-occurrence of genes encoding carbapenemase, ESBL, pAmpC and non-ß-Lactam resistance among Klebsiella pneumonia and E. coli clinical isolates in Tunisia.

This study aimed to investigate the molecular mechanisms of carbapenem and colistin resistance in K. pneumoniae and E. coli isolates obtained from hospitalized patients in Carthagene International Hospital of Tunis. A total of 25 K. pneumoniae and 2 E. coli clinical isolates with reduced susceptibility to carbapenems were recovered. Susceptibility testing and phenotypic screening tests were carried out. ESBL, AmpC, carbapenemase and other antibiotic resistance genes were sought by PCR-sequencing. The presence of plasmid-mediated colistin resistance genes (mcr-1-8) was examined by PCR and the nucleotide sequence of the mgrB gene was determined. The analysis of plasmid content was performed by PCR-Based Replicon Typing (PBRT). The clonality of isolates was assessed by PFGE and multilocus sequence typing (MLST). All of the isolates produced carbapenemase activity. They showed a great variation in the distribution of ESBL, AmpC, carbapenemase and other plasmid-mediated resistance determinants. K. pneumoniae isolates carried blaNDM-1 (n = 11), blaOXA-48 (n = 11), blaNDM-1 + blaOXA-48 (n = 1), blaNDM-1 + blaVIM-1 (n = 1), blaOXA-204 (n = 1), along with blaCTX-M , blaOXA , blaTEM , blaCMY , blaDHA and blaSHV genes variants on conjugative plasmid of IncL/M, IncR, IncFIIK , IncFIB, and IncHI1 types. Three sequence types ST101, ST307 and ST15 were identified. The mgrB alteration g109a (G37S) was detected in a single colistin-resistant, NDM-1 and OXA-48-coproducing K. pneumoniae isolate. The two E. coli isolates belonged to ST95, co-produced NDM-1 and CTX-M-15, and harboured plasmid of IncFII and IncFIB types. To our knowledge, this is the first report in Tunisia of NDM-1, OXA-48, and CTX-M-15 coexistence in colistin-resistant K. pneumoniae ST15.

Analysis of wall shear stress around a competitive swimmer using 3D Navier-Stokes equations in CFD.

This paper deals with the flow dynamics around a competitive swimmer during underwater glide phases occurring at the start and at every turn. The influence of the head position, namely lifted up, aligned and lowered, on the wall shear stress and the static pressure distributions is analyzed. The problem is considered as 3D and in steady hydrodynamic state. Three velocities (1.4 m/s, 2.2 m/s and 3.1 m/s) that correspond to inter-regional, national and international swimming levels are studied. The flow around the swimmer is assumed turbulent. The Reynolds-averaged Navier-Stokes (RANS) equations are solved with the standard k-ω turbulent model by using the CFD (computational fluid dynamics) numerical method based on a volume control approach. Numerical simulations are carried out with the ANSYS FLUENT® CFD code. The results show that the wall shear stress increases with the velocity and consequently the drag force opposing the movement of the swimmer increases as well. Also, high wall shear stresses are observed in the areas where the body shape, globally rigid in form, presents complex surface geometries such as the head, shoulders, buttocks, heel and chest.

Epidemiological profile of snakebites in Morocco

The present work aims to find the epidemiological profile of snakebites in Morocco through a retrospective study of 1,423 snakebite cases that occurred between 1992 and 2007. Data were obtained from medical charts of envenomation at the Poison Control and Pharmacovigilance Center of Morocco. Results revealed that 86 percent of the snakebites had occurred in rural areas and that males were significantly more affected than females at a sex ratio of 23:20. Furthermore, 35 percent of the bites happened during the summer, with a peak of 215 cases in June (15.1 percent). We also discovered that 67.3 percent of the patients were bitten during the day. The age group that comprised the most agriculturally active persons, from 20 to 44 years old, was the most affected by snakebites (551 cases). In terms of evolution, patients who were at least 60 years of age (8.89 percent) as well as those who were less than 10 years old (7.50 percent) presented higher mortality. According to clinical severity grades, the data revealed a 70 percent predominance of grade 2 cases (430). Deaths had occurred only in patients with grades 3 and 4. Furthermore, grade 4 patients presented 100 percent mortality whereas grade 3 registered 10.7 percent. The distribution of snakebites according to administrative regions in Morocco showed a predominance of the Souss-Massa-Daraa region both in terms of frequency (32 percent) and mortality (72.1 percent). Our study clearly displayed the severity and extent of the snakebite problem in the country, thus revealing that public health authorities should give more attention to this serious situation.(AU)

Preventive effects of flaxseed and sesame oil on bone loss in ovariectomized rats.

A study was designed to examine the effects of dietary flaxseed oil (FO) and sesame oil (SO) which are rich successively in n-3 and (n-9 and n-6) on biochemical parameters and histological status of bone. Sixty-four 90-day-old female wistar rats were randomly assigned to 6 groups: sham-operated rat (sham)+ control diets, ovariectomized rat (OVX) + control diets, OVX + 7% FO, OVX + 7% SO, OVX + 10% FO, OVX + 10% SO. After 4 weeks of treatments, rats were euthanized; blood and tissues were collected for analyses. Markers of bone formation which is alkaline phosphatase activity and markers of bone resorption which is tartrate resistant acid phosphatase activity were measured. Present results showed that OVX increased significantly ALP and TRAP activity and the examination of bone tissue showed disruptive and lytic bone trabeculae. Animals fed 10% FO and 10% SO of fat reduced these parameters and improved bone microarchitecture. Whereas, there was no improvement in biochemical and histological states in OVX rats that received 7% of PUFAs successively provided from FO and SO diets. In conclusion, our results are encouraging because they suggest that PUFAs intake may help to prevent osteoporosis associated with estrogens deficiency. However, further studies are needed to determine the mechanism by which a diet rich in n-3 or lignans modulate bone tissue.

Risk factors caused by scorpion stings and envenomations in the province of Kelâa Des Sraghna (Morocco)

The present study aims to elucidate the risk factors involved in deaths caused by scorpion envenomation. A retrospective study was carried out in the province of Kelâa des Sraghna from 2003 to 2004. The hospital charts of scorpion envenomation cases treated in the Essalama Hospital in Kelâa des Sraghna were exhaustively analyzed. Our study contains 31 cases of death among 470 hospitalization cases. Most stings had occurred during the hot period peaking in July and August (54.6%). Moreover, the scorpion stings occurred at night in 60.1% of the cases, between 6:00 pm and 6:00 am. In addition, all age groups were affected by envenomation, with a higher frequency in children aged less than 15 years (68.3%). The envenomation rate (class II + class III) was 70.9%. The statistical analysis of the data shows that being less than 15 years old, having been stung during the night and belonging to class III are risk factors that aggravate vital prognosis of hospitalized patients. Furthermore, clinical severity factors, elicited by relative risk analysis, are cardiovascular, respiratory and neurological vital distresses, with relative risks of 14.84, 11.92 and 48.33, respectively. The results of our study clearly displayed the severity and extent of the scorpion envenomation problem. Thus, great attention must be paid to this region of Morocco by the national health authorities.(AU)

Treatment of chickpea with Rhizobium isolates enhances the expression of phenylpropanoid defense-related genes in response to infection by Fusarium oxysporum f. sp. ciceris.

Differential expression of phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS) and isoflavone reductase (IFR) genes involved in phenylpropanoids metabolism was investigated using Northern blot analyses in chickpea seedlings bacterized with Rhizobium isolates (PchDMS and Pch43) and further challenged with Fusarium oxysporum f. sp. ciceris (Foc) race 0. Gene activation patterns in the moderately resistant accession INRAT87/1 were compared with those exhibited by the susceptible accession ILC482 at various time intervals after inoculation with Foc, to determine whether differences in levels or timing of transcript accumulation could be correlated with differences in the susceptibility of chickpea accessions to Foc. Gene activation was higher in the moderately resistant accession INRAT87/1 than in the susceptible ILC482. Pre-treatment of chickpea seedlings with Rhizobium isolates before inoculation with the pathogen enhanced the accumulation of the three genes' mRNA transcripts. In parallel, changes in the soluble phenolic pool produced through pathways involving these enzymes were analyzed in chickpea roots. A strong accumulation of these compounds was revealed at 72 hpi in both accessions. After that time, these high levels of phenolic compounds were maintained until the end of the experiment in the moderately resistant accession, while they have significantly declined in the susceptible accession. HPLC analyses revealed a very high accumulation of the constitutive isoflavones, formononetin and biochanin A and their glycoside conjugates in chickpea roots inoculated with Rhizobium isolates and/or challenged with Foc, as compared to the controls. Our results suggest that the increased accumulation of phenolic compounds, observed in chickpea seedlings inoculated with Foc, can be attributed to increased expression of genes in the phenylpropanoid pathway and that such gene expression is enhanced by pre-treatment with Rhizobium isolates.

[Production of avian infectious bursitis virus by in vivo DNA genomic transcription]. / Production du virus de la bursite infectieuse aviaire (IBDV) par transcription in vivo de l'ADNc génomique.

Generation of infectious particles of infectious bursal disease virus (IBDV) has been essentially performed by transfecting susceptible cells with in vitro synthesized cRNAs of genomic segments A and B. In the present study, we have explored the possibility to proceed directly in vivo without taking into account the extra-genomic vector-derived sequences. For this purpose, cDNAs of segments A and B were subcloned into an eucaryotic expression vector under the control of the immediate early CMV promoter. Upon transfection of primary culture of chicken embryonic fibroblasts with both constructs, a cytopathic effect (CPE) typical of that produced by IBDV could be observed, indicating that the 5'- and 3'- vector-derived extra-nucleotides did not interfere with the replication and packaging process. Finally, in order to develop a GFP-based packaging assay, we first tried to express this fluorescent protein in the context of the IBDV polyprotein encoded by the genomic segment A. Our initial results indicate that the presence of IBDV specific sequences upstream of the GFP polypeptide dramatically decreased the fluorescence of the latter protein.