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Stored grains could lose substantially their nutritional quality, and consequently its value, between storage and consummation because of insect’s infestation. One of the most frequent pests of wheat is the grain weevil (Sitophilus granarius L.). Cleverly hidden, the immature stages of this destructive pest are very difficult to identify. Protecting stored grains has become an agricultural challenge. In the present study, the essential oil (EO) distillated from Citrus limonum (L.) (Burm. F., 1768) and analyzed by gas chromatography-mass spectrometry (GC-MS) revealed the presence of 47 compounds with (Z)-citral (30.74%), dl-limonene (19.81%) and geranyl propionate (16.28%) as major components. In a second series of experiment, its fumigant (using filter paper), repellent (by semi circles joined discs) and residual (persistent insecticidal activity) activities were examined against Sitophilus granarius (L.) adults. The total nutrition (carbohydrates and lipids) depletion index (NDI) was also calculated. Residual toxicity and repellency of EO were demonstrated after fumigation against S. granarius with a dose-response relationship. The effectiveness of EO was exposure time dependent and its residual activity persisted up to 30 h following mortality. Moreover, data showed that treatment of S. granarius adults had adverse effects on the depletion of their energy reserves. C. limonum EO declined the lipid and carbohydrate contents in adults. Obtained data prove that botanical essential oils could be considered as potent biorational alternatives to synthetic insecticides for pest control of stored products in a sustainable manner.

Background Reduced mortality at 28 days in patients treated with corticosteroids was demonstrated, but this result was not confirmed by certain large epidemiological studies. Our aim was to determine whether corticosteroids improve the outcomes of our patients hospitalized with COVID-19 pneumonia. Methods Our retrospective, single centre cohort study included consecutive patients hospitalized for moderate to severe COVID-19 pneumonia between March 15 and April 15 2020. An early short course of corticosteroids was given during the second phase of the study. The primary composite endpoint was the need for mechanical ventilation or mortality within 28 days of admission. A multivariate logistic regression model was used to estimate the propensity score, i.e. the probability of each patient receiving corticosteroid therapy based on the initial variables. Results About 120 consecutive patients were included, 39 in the “corticosteroids group”, 81 in the “no corticosteroids group”; their mean ages (±SD) were 66.4 ± 14.1 and 66.1 ± 15.2 years, respectively. Mechanical ventilation-free survival at 28 days was higher in the “corticosteroids group” than in the “no corticosteroids group” (71% and 29% of cases, respectively, p

The present study was undertaken in order to determine the chemical composition of the leaf Essential Oils (EOs) of five plants (Ocimum basilicum, Lavandula dentata, Mentha piperita, Mentha pulegium, and Laurus nobilis) cultivated in Tebessa (Algeria) and to assess their potential larvicidal activity against the most abundant and investigated mosquito species, Culex pipiens L., 1758 (Diptera, Culicidae). The Essential Oils (EOs) were tested at different concentrations on newly molted 4th instar larvae. The effects of the activities of Acetylcholinesterase (AChE) and Glutathione-S-Transferases (GSTs) on mortality were examined. Their chemical compositions were investigated by GC/MS. The major components of M. pulegium, L. dentata, M. piperita, O. basilicum, and L. nobilis were Pulegone (72.50%), α-Terpinolene (51.13%), Carvone (30.27%), Linalyl acetate (53.89%), and Eucalyptol (47.35%), respectively. The larval mortality was observed after 24 h of exposure. Dose-response relationship was determined for all tested plants EOs. L. nobilis EO was the most effective against C. pipiens, comparatively to the other tested oils. The enzymatic measurements performed in LC50 treated larvae revealed a neurotoxic activity and a stimulation of the detoxification system with evidenced by the inhibition of AChE and an increase in GST activity, respectively. The EOs from tested plants could be an alternative measure for the control of C. pipiens as they contain an efficient source of bioactive compounds, which are generally free from health hazards and environmental pollution.

In this study, the chemical composition of Lavandula angustifolia essential oil (EO) has been determined by gas chromatography-mass spectrometry (GC/MS). Then, we have evaluated the fumigant toxicity, the repellent and antifeedant properties of this EO on the adult of Rhyzopertha dominica. GC-MS analysis showed that this oil contains 56 compounds of linalool (20.42%) and linalyl acetate (13.24%) as the major components. This essential oil was found to exhibit insecticidal activity depending on the concentration and exposure period. In addition, the obtained results revealed an increase in the percent repellency. EO was investigated in the digestive enzymes activity. Results showed a decrease in α-amylase and protease activities in treated series (LC50) compared to control. Lastly, EO was investigated on food intake. Results showed a potential antifeedant in treated series compared to control. This study has highlighted a bioinsecticide activity of L. angustifolia against insect pests of stored product (R. dominica). The Lavandula essential oil offers an interesting potential insecticide that could be studied more deeply to isolate and identify the active substances.

Although stored grains can be destroyed by insects, fungi, and vertebrate pests, insect pests are often the most important devastators because of the favourable environmental conditions that promote their development.

The cockroach, Blatta orientalis, is among one of the important domestic pests found in the semi-arid areas of Algeria. In this study, the insecticidal activity of spinosad, bioinsecticide, was tested against B. orientalis using different concentrations. Bioassays were done by topical application on newly emerged adult females under laboratory conditions. The results showed that the product exhibits a high level of toxicity with a dose-response relationship. The enzymatic analyses of the treated adults of B. orientalis with the determined LC50 dose revealed a neurotoxic activity of spinosad, with an inhibition of acetylcholinesterase and a stimulation of the detoxification system that is interpreted by the increase of glutathione-S-transferase activity. In other experiments the compound was applied at LC50 on a newly emerged females and its effect was investigated on reproduction during the first gonadotrophic cycle (0, 2, 4 and 6 days) and the ovarian protein contents. The results showed that spinosad re...

Fiche Situations de soins : Madame M., âgee de 80 ans, est hospitalisee en medecine geriatrique pour une perte d’autonomie en lien avec l’evolution d’une masse tumorale de la cuisse gauche. L’aspect clinique de cette tumeur rare des tissus mous est exemplaire. (R.E.)

As a result of the increased life expectancy, elderly with acute coronary syndromes (ACS) referred to coronary catheterization facilities for emergency percutaneous coronary interventions (PCI) increase in numbers. Whereas PCI has proven effective in this setting, management of elderly with ACS remains a challenging issue. Concerns about benefit-risk ratio include physiological age and associated co-morbidities such as renal and/or cognitive impairment.

Earthworms are important soil macroinvertebrates and are often used in assessing soil pollution. The present study was conducted in order to investigate the effect of two compounds, triple superphosphate (TSP; fertilizer), sekator (herbicide), and their mixture at two agricultural doses on a Lumbricus terrestris population. Neurotoxicity (acetylcholinesterase (AChE)), metabolization (glutathione-S-transferase (GST)), glutathione (GSH), and protein content were evaluated as biomarkers. Treated earthworms with sekator showed a non-significant increase of protein content (p > 0.05). In contrast, protein content increased significantly (p

A study was performed to estimate the prevalence of the external bacterial flora of two domestic cockroaches (Blattella germanica and Blatta orientalis) collected from households in Tebessa (northeast Algeria). Three major bacterial groups were cultured (total aerobic, enterobacteria, and staphylococci) from 14 specimens of cockroaches, and antibiotic susceptibility was tested for both Staphylococcus and Pseudomonas isolates. Culturing showed that the total bacterial load of cockroaches from different households were comparable (P0.001) and enterobacteria were the predominant colonizers of the insect surface, with a bacterial load of (2.1 × 10⁵ CFU/insect), whereas the staphylococci group was the minority. Twenty-eight bacterial species were isolated, and susceptibility patterns showed that most of the staphylococci isolates were highly susceptible to chloramphenicol, gentamycin, pristinamycin, ofloxacin, clindamycin, and vancomycin; however, Pseudomonas strains exhibited resistance to amoxicillin/clavulanic acid, imipenem, and the second-generation antibiotic cephalosporin cefuroxime.

In this work, the toxicity of azadirachtin applied topically at various doses (300, 600, 1200, 2400, 4800 and 9000 ng/ insect) was evaluated against newly emerged adults of the oriental cockroach, Blatta orientalis L. (Dictyoptera, Blattellidae) under laboratory conditions. Results show that treated insects exhibited toxic symptoms with a dose-dependent mortality. In a second series of experiments, the compound applied topically at its LD50 and LD90 on newly emerged female adults was investigated on ovarian growth during the first gonadotrophic cycle (0, 2, 4 and 6 days). Azadirachtin was found to reduce the number of oocytes per paired ovaries and the size of basal oocytes. Furthermore, the compound was examined on ovarian biochemical components. Biochemical data revealed a significant reduction of ovarian contents of proteins, lipids and carbohydrates with the two tested doses. The overall results suggest an interference of the compounds with the vitellogenesis.Key words: Azadirachtin, Blatta orientalis, toxicity, reproduction, ovary, biochemical components.

Background and Purpose— Risk of tumorigenesis is a major obstacle to human embryonic and induced pluripotent stem cell therapy. Likely linked to the stage of differentiation of the cells at the time of implantation, formation of teratoma/tumors can also be influenced by factors released by the host tissue. We have analyzed the relative effects of the stage of differentiation and the postischemic environment on the formation of adverse structures by transplanted human embryonic stem cell-derived neural progenitors. Methods— Four differentiation stages were identified on the basis of quantitative polymerase chain reaction expression of pluripotency, proliferation, and differentiation markers. Neural progenitors were transplanted at these 4 stages into rats with no, small, or large middle cerebral artery occlusion lesions. The fate of each transplant was compared with their pretransplantation status 1 to 4 months posttransplantation. Results— The influence of the postischemic environment was limited to graft survival and occurrence of nonneuroectodermal structures after transplantation of very immature neural progenitors. Both effects were lost with differentiation. We identified a particular stage of differentiation characterized in vitro by a rebound of proliferative activity that produced highly proliferative grafts susceptible to threaten surrounding host tissues. Conclusion— The effects of the ischemic environment on the formation of teratoma by transplanted human embryonic stem cell-derived neural progenitors are limited to early differentiation stages that will likely not be used for stem cell therapy. In contrast, hyperproliferation observed at later stages of differentiation corresponds to an intrinsic activity that should be monitored to avoid tumorigenesis.