75 research outputs found
Study of trophic relationships between diaspididae family species -host plants -predators and parasitoids in Algeria
The use of parasitoids and predators in biocontrol contribute to the development of sustainable agriculture, respects environment and human health. In this context, we undertook the identification of natural Diaspididae enemies located on the Algerian territory. Results highlight three predatory families: Coccinellidae, Nitidulidae and Coniopterygidae families, the first represented by the most voracious species as Rhyzobius lophantae living on 19 Diaspines observed on 121 plants, from the northern, and two parasitoid families lived on 39 Diaspididae species affecting 125 plants and were represented by four genera and 23 species such as Aphytis and Encarcia (Aphelinidae) lived on 31 diaspididae species found on 125 host plants. The most voracious and polyphagous species identified are interesting for IPM.Keywords: Diaspididae, Predators, Parasitoids, Host-plant, Algeri
Study of genitalia morphometric variability of the two Species Helix aperta and Helix aspersa (gasteropoda, pulmonata)
Our research aims for, firstly, the study of genitalia morphometric variability of the two species Helix aperta and Helix aspersa, and the relation of this variability with individual’s weight and shell size. Secondly, differences in dimensions of the genital organs between the two studied species were investigated. This study showed, first, the existence of an important dimensional variability of genital organs in both studied species, then, a positive correlation between organs’ measurements and those of weight and shell. Finally, two genital organs, that are flagellum and proximal duct of bursa copulatrix, proved to be interesting to discriminate between the two species Helix aperta and Helix aspersa, because both organs are greater in Helix aspersa.Key-words: Genitalia, Helix aperta, Helix aspersa, morphometric variability, positive correlation, weight, shell size, discriminating characters
Flowering plants preferred by native wild bees (hymenoptera, apoidea, apiformes) in the Algerian Littoral Region
This study considered the plant floral resources visited by native wild and honey bees in Algiers (northern Algeria). Three botanical families accounted for almost 2/3 of all visits: Asteraceae (44.1%), Boraginaceae (15.3%) and Brassicaceae (13%). Plants in other families were visitedless frequently (e.g.Ranunculaceae (0.1%)). At the species level, the most frequently visited plant was Anchusa azurea (Boraginaceae), reaching 15.2% of the total bee visitation. Our work showed that Apis mellifera Linnaeus, 1758 is, typically, a polylectic species and that the majority of solitary bees exhibited the more specialised trait of oligolectics. The narrowest trophic niche varied between 0.01 and 0.06 bits for Halictus rufipes (Fabricius, 1793), Halictus scabiosae (Rossi, 1790) (Halictidae), Osmia pinguis Pérez, 1895 and Osmia tricornis Linnaeus, 1811 (Megachilidae).Key-words: Wild bees, floral choices, natural habitat, northern of Algeria
Time to revise classification of phyllodes tumors of breast? Results of a French multicentric study
OBJECTIVE: To assess prognostic factors of recurrence of phyllodes tumors (PT) of the breast.
METHODS: We performed a retrospective, multicentric cohort study, including all patients who underwent breast surgery for grade 1 (benign), 2 (borderline) or 3 (malignant) PT between 2000 and 2016 in five tertiary University hospitals, diagnosed according to World Health Organisation classification.
RESULTS: 230 patients were included: 144 (63%), 60 (26%) and 26 (11%) with grade 1, 2 and 3 PT, respectively. Recurrence occurred in 10 (7%), 7 (12%) and 5 (19%) patients with grade 1, 2 and 3 PT, respectively. In univariate analysis, moderate to severe nuclear stromal pleomorphism (HR 8.00 [95% CI: 1.65-38.73], p < 0.009) was correlated with recurrence in all groups including grade 1 (HR 14.3 [95% CI: 1.29-160], p = 0.031). In multivariate analysis, surgical margin >5 mm, (HR 0.20 [95% CI: 0.06-0.63], p = 0.013) were significantly correlated with less recurrence in all PT grades. For grade 1 PT, there was also significantly less recurrence with surgical margin >5 mm, (HR 0.09 [95% CI: 0.01-0.85], p = 0.047) in multivariate analysis.
CONCLUSION: The surgical margin should be at least 5 mm whatever the grade of PT. Moderate to severe nuclear stromal pleomorphism identified a subgroup of grade 1 PT with a higher rate of recurrence. This suggests that the WHO classification could be revised with the introduction of nuclear stromal pleomorphism to tailor PT management
Intracellular delivery of an anionic antisense oligonucleotide via receptor-mediated endocytosis
We describe the synthesis and characterization of a 5′ conjugate between a 2′-O-Me phosphorothioate antisense oligonucleotide and a bivalent RGD (arginine–glycine–aspartic acid) peptide that is a high-affinity ligand for the αvβ3 integrin. We used αvβ3-positive melanoma cells transfected with a reporter comprised of the firefly luciferase gene interrupted by an abnormally spliced intron. Intranuclear delivery of a specific antisense oligonucleotide (termed 623) corrects splicing and allows luciferase expression in these cells. The RGD–623 conjugate or a cationic lipid-623 complex produced significant increases in luciferase expression, while ‘free’ 623 did not. However, the kinetics of luciferase expression was distinct; the RGD–623 conjugate produced a gradual increase followed by a gradual decline, while the cationic lipid-623 complex caused a rapid increase followed by a monotonic decline. The subcellular distribution of the oligonucleotide delivered using cationic lipids included both cytoplasmic vesicles and the nucleus, while the RGD–623 conjugate was primarily found in cytoplasmic vesicles that partially co-localized with a marker for caveolae. Both the cellular uptake and the biological effect of the RGD–623 conjugate were blocked by excess RGD peptide. These observations suggest that the bivalent RGD peptide–oligonucleotide conjugate enters cells via a process of receptor-mediated endocytosis mediated by the αvβ3 integrin
Inhibition of Multidrug Resistance by SV40 Pseudovirion Delivery of an Antigene Peptide Nucleic Acid (PNA) in Cultured Cells
Peptide nucleic acid (PNA) is known to bind with extraordinarily high affinity and sequence-specificity to complementary nucleic acid sequences and can be used to suppress gene expression. However, effective delivery into cells is a major obstacle to the development of PNA for gene therapy applications. Here, we present a novel method for the in vitro delivery of antigene PNA to cells. By using a nucleocapsid protein derived from Simian virus 40, we have been able to package PNA into pseudovirions, facilitating the delivery of the packaged PNA into cells. We demonstrate that this system can be used effectively to suppress gene expression associated with multidrug resistance in cancer cells, as shown by RT-PCR, flow cytometry, Western blotting, and cell viability under chemotherapy. The combination of PNA with the SV40-based delivery system is a method for suppressing a gene of interest that could be broadly applied to numerous targets
Pollinator-flower interactions in gardens during the COVID-19 pandemic lockdown of 2020
During the main COVID-19 global pandemic lockdown period of 2020 an impromptu set of pollination ecologists came together via social media and personal contacts to carry out standardised surveys of the flower visits and plants in gardens. The surveys involved 67 rural, suburban and urban gardens, of various sizes, ranging from 61.18° North in Norway to 37.96° South in Australia, resulting in a data set of 25,174 rows, with each row being a unique interaction record for that date/site/plant species, and comprising almost 47,000 visits to flowers, as well as records of flowers that were not visited by pollinators, for over 1,000 species and varieties belonging to more than 460genera and 96plant families. The more than 650 species of flower visitors belong to 12 orders of invertebrates and four of vertebrates. In this first publication from the project, we present a brief description of the data and make it freely available for any researchers to use in the future, the only restriction being that they cite this paper in the first instance. The data generated from these global surveys will provide scientific evidence to help us understand the role that private gardens (in urban, rural and suburban areas) can play in conserving insect pollinators and identify management actions to enhance their potential
Impact of fungicides on the performance of ten varieties of 4 potato newly introduced in Algeria
The potato is an increasingly important food in Algeria. Domestic production has increased in recent years due to high consumption. Faced with this increase in consumption, it is necessary to produce quality potatoes from the point of production yield. The present work aims to study the variability of potato production in relation to the production areas. On the other hand, newly introduced variety trials are conducted treated with fungicides. The yield results show that the Challenger and Synergy white-skinned varieties are the most profitable, the production has reached more than 350Qx / ha with a yield index greater than 100%, they have shown resistance to fungal diseases in contrast to varieties Lusa and Senna, which reacted negatively even with the foliar treatment, their yield is very low. Keywords: Algeria, fungicide, potato, yield, varieties
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