Phytochemical composition of Cymbopogon citratus and Eucalyptus citriodora essential oils and their anti-inflammatory and analgesic properties on Wistar rats

Cymbopogon citratus and Eucalyptus citriodora are widely used herbs/plants as a source of ethnomedicines in tropical regions of the world. In this work, we studied the anti-inflammatory and gastroprotective effects of C. citratus and E. citriodora essential oils on formol-induced edema, and acetic acid induced abdominal cramps in Wistar rats. To fully understand the chemically induced anti-inflammatory properties of these plants, we first analyzed the chemical composition of the essential oils. A total of 16 chemical constituents accounting for 93.69 % of the oil, were identified in C. citratus among which, Geranial (27.04 %), neral (19.93 %) and myrcene (27.04 %) were the major constituents. For E. citriodora, 19 compounds representing 97.2 % of the extracted oil were identified. The dominant compound of E. citriodora essential oil was citronellal (83.50 %). In vivo analysis and histological assay showed that the two essential oils displayed significant dose dependent edema inhibition effect over time. They displayed strong analgesic and antipyretic properties similar to that induced by 50 mg/kg of acetylsalicylate of lysine. However, the E. citriodora essential oil was more effective than that of C. citratus. We identified significant numbers of aldehyde molecules in both essential oils mediating antioxidant activity that may contribute to the anti-inflammatory effects observed on the rats. Altogether, this work demonstrates the anti-inflammatory property of C. citratus and E. citriodora suggesting their potential role as adjuvant therapeutic alternatives in dealing with inflammatory-related diseases.     

Planar Cell Polarity Pathway Regulates Nephrin Endocytosis in Developing Podocytes

The noncanonical Wnt/planar cell polarity (PCP) pathway controls a variety of cell behaviors such as polarized protrusive cell activity, directional cell movement, and oriented cell division and is crucial for the normal development of many tissues. Mutations in the PCP genes cause malformation in multiple organs. Recently, the PCP pathway was shown to control endocytosis of PCP and non-PCP proteins necessary for cell shape remodeling and formation of specific junctional protein complexes. During formation of the renal glomerulus, the glomerular capillary becomes enveloped by highly specialized epithelial cells, podocytes, that display unique architecture and are connected via specialized cell-cell junctions (slit diaphragms) that restrict passage of protein into the urine; podocyte differentiation requires active remodeling of cytoskeleton and junctional protein complexes. We report here that in cultured human podocytes, activation of the PCP pathway significantly stimulates endocytosis of the core slit diaphragm protein, nephrin, via a clathrin/β-arrestin-dependent endocytic route. In contrast, depletion of the PCP protein Vangl2 leads to an increase of nephrin at the cell surface; loss of Vangl2 functions in Looptail mice results in disturbed glomerular maturation. We propose that the PCP pathway contributes to podocyte development by regulating nephrin turnover during junctional remodeling as the cells differentiate.     

Arbuscular mycorrhizal symbiosis can counterbalance the negative influence of the exotic tree species Eucalyptus camaldulensis on the structure and functioning of soil microbial communities in a sahelian soil

The hypothesis of the present study was that bacterial communities would differentiate under Eucalyptus camaldulensis and that an enhancement of arbuscular mycorrhizal (AM) density would minimize this exotic plant species effect. Treatments consisted of control plants, preplanting fertilizer application and AM inoculation. After 4 months of culture in autoclaved soil, E. camaldulensis seedlings were either harvested for growth measurement or transferred into containers filled with the same soil but not sterilized. Other containers were kept without E. camaldulensis seedlings. After 12 months, effects of fertilizer amendment and AM inoculation were measured on the growth of Eucalyptus seedlings and on soil microbial communities. The results clearly show that this plant species significantly modified the soil bacterial community. Both community structure (assessed by denaturing gradient gel electrophoresis profiles) and function (assessed by substrate-induced respiration responses including soil catabolic evenness) were significantly affected. Such changes in the bacterial structure and function were accompanied by disturbances in the composition of the herbaceous plant species layer. These results highlight the role of AM symbiosis in the processes involved in soil bio-functioning and plant coexistence and in afforestation programmes with exotic tree species that target preservation of native plant diversity.     

Antagonistic activity of <Emphasis Type="Italic">Bacillus</Emphasis> sp. obtained from an Algerian oilfield and chemical biocide THPS against sulfate-reducing bacteria consortium inducing corrosion in the oil industry

The present study enlightens the role of the antagonistic potential of nonpathogenic strain B21 against sulfate-reducing bacteria (SRB) consortium. The inhibitor effects of strain B21 were compared with those of the chemical biocide tetrakishydroxymethylphosphonium sulfate (THPS), generally used in the petroleum industry. The biological inhibitor exhibited much better and effective performance. Growth of SRB in coculture with bacteria strain B21 antagonist exhibited decline in SRB growth, reduction in production of sulfides, with consumption of sulfate. The observed effect seems more important in comparison with the effect caused by the tested biocide (THPS). Strain B21, a dominant facultative aerobic species, has salt growth requirement always above 5% (w/v) salts with optimal concentration of 10–15%. Phylogenetic analysis based on partial 16S rRNA gene sequences showed that strain B21 is a member of the genus Bacillus, being most closely related to Bacillus qingdaonensis DQ115802 (94.0% sequence similarity), Bacillus aidingensis DQ504377 (94.0%), and Bacillus salarius AY667494 (92.2%). Comparative analysis of partial 16S rRNA gene sequence data plus physiological, biochemical, and phenotypic features of the novel isolate and related species of Bacillus indicated that strain B21 may represent a novel species within the genus Bacillus, named Bacillus sp. (EMBL, FR671419). The results of this study indicate the application potential of Bacillus strain B21 as a biocontrol agent to fight corrosion in the oil industry.     

High accumulation of dehydrodiconiferyl alcohol-4-β-d-glucoside in free and immobilized Linum usitatissimum cell cultures

As flaxseed mainly accumulates lignans (secoisolariciresinol diglucoside and matairesinol), these compounds were barely or not detected in plant cell suspensions initiated from Linum usitatissimum. In contrast, these cell suspensions were shown to accumulate substantial amounts of a neolignan identified as dehydrodiconiferyl alcohol-4-β-d-glucoside (DCG) (up to 47.7 mg g⁻¹ DW). The formation of this pharmacologically active compound was evaluated as a function of cell growth and in relation to phytohormone balance of the culture media. After establishment of efficient culture conditions, production of DCG was investigated in immobilized plant cell suspensions initiated from plantlet roots of L. usitatissimum. The results indicate that immobilization enhances the DCG production up to 60.0 mg g⁻¹ DW but depresses the cell growth resulting in no improvement of the total DCG yield. Nevertheless, with immobilized cell suspensions, a release of DCG into the medium is observed allowing an easier recovery.     

Lésions des organes génitaux externes par arme a feu: a propos de six observations

Patients and Methods

This is a retrospective study of patients admitted with gunshot injuries to the external genital organs to the urology departments of Aristide Le Dantec Hospital, Grand Yoff General Hospital and Dakar Principal Hospital, between January 1998 and January 2003. The following parameters were studied: patients’ age and gender, interval between accident and admission, clinical features, complementary investigations and treatment, and early and late outcomes.

Results

Only males were observed and the mean age of these patients was 37.7 years (range: 22–52 years). Lesions were accidental in five cases. Two cases of testicular wounds, two cases of corpus cavernosum injuries, two cases of urethral injury, and one case of perineal wound were observed. After excision of the lesions, complementary procedures consisted of: orchidectomy in two cases, corpus cavernosum — albuginea suture in two cases and end-to-end urethral suture in one case. Perineoscrotal wounds were sutured three days after debridement. All patients received antibiotics and antitetanus serum. No death was observed during the immediate follow-up. No case of urethral stricture or erectile dysfunction was observed with a follow-up of 18 months. Semen analysis was normal in the two cases of orchidectomy.     

Sangassou virus, the first hantavirus isolate from Africa, displays genetic and functional properties distinct from those of other murinae-associated hantaviruses

We have discovered the first indigenous African hantavirus, Sangassou virus (SANGV). The virus was isolated from an African wood mouse (Hylomyscus simus), trapped in a forest habitat in Guinea, West Africa. Here, we report on the characterization of the genetic and functional properties of the virus. The complete genome of SANGV was determined and showed typical hantavirus organization. The small (S), medium (M), and large (L) genome segments containing genes encoding nucleocapsid protein, two envelope glycoproteins, and viral polymerase were found to be 1,746, 3,650, and 6,531 nucleotides long, respectively. The exact 5' and 3' termini for all three segments of the SANGV genome were determined and were predicted to form the panhandle structures typical of bunyaviruses. Phylogenetic analyses of all three segment sequences confirmed SANGV as a Murinae-associated hantavirus most closely related to the European Dobrava-Belgrade virus. We showed, however, that SANGV uses β(1) integrin rather than β(3) integrin and decay-accelerating factor (DAF)/CD55 as an entry receptor. In addition, we demonstrated a strong induction of type III lambda interferon (IFN-λ) expression in type I IFN-deficient Vero E6 cells by SANGV. These properties are unique within Murinae-associated hantaviruses and make the virus useful in comparative studies focusing on hantavirus pathogenesis.     

Recognition of aminoacyl-tRNA: a common molecular mechanism revealed by cryo-EM

The accuracy of ribosomal translation is achieved by an initial selection and a proofreading step, mediated by EF-Tu, which forms a ternary complex with aminoacyl(aa)-tRNA. To study the binding modes of different aa-tRNAs, we compared cryo-EM maps of the kirromycin-stalled ribosome bound with ternary complexes containing Phe-tRNA^Phe, Trp-tRNA^Trp, or Leu-tRNA^LeuI. The three maps suggest a common binding manner of cognate aa-tRNAs in their specific binding with both the ribosome and EF-Tu. All three aa-tRNAs have the same ‘loaded spring' conformation with a kink and twist between the D-stem and anticodon stem. The three complexes are similarly integrated in an interaction network, extending from the anticodon loop through h44 and protein S12 to the EF-Tu-binding CCA end of aa-tRNA, proposed to signal cognate codon–anticodon interaction to the GTPase centre and tune the accuracy of aa-tRNA selection.