The profession of firefighter working on the rescue and emergency care involves many skills and requirements. The Health Sub-Directorate's supervisory division oversees the activities of these agents in partnership with the Operations, Forecasting and Prevention Division. A firefighter nurse is present on the site and watches over the 250 to 350 daily interventions.
View Article and Find Full Text PDFBecause aphids are global agricultural pests and models for bacterial endosymbiosis, there is a need for reliable methods to study and control their gene function. However, current methods available for aphid gene knockout and knockdown of gene expression are often unreliable and time consuming. Techniques like CRISPR-Cas genome editing can take several months to achieve a single gene knockout because they rely on aphids going through a cycle of sexual reproduction, and aphids often lack strong, consistent levels of knockdown when fed or injected with molecules that induce an RNA interference (RNAi) response.
View Article and Find Full Text PDFPea aphids (Acyrthosiphon pisum) are insects containing genes of bacterial origin with putative functions in peptidoglycan (PGN) metabolism. Of these, rlpA1-5, amiD, and ldcA are highly expressed in bacteriocytes, specialized aphid cells that harbor the obligate bacterial symbiont Buchnera aphidicola, required for amino acid supplementation of the host's nutrient-poor diet. Despite genome reduction associated with endosymbiosis, pea aphid Buchnera retains genes for the synthesis of PGN while Buchnera of many other aphid species partially or completely lack these genes.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 2021
Numerous animal lineages have maternally inherited symbionts that are required for host reproduction and growth. Endosymbionts also pose a risk to their hosts because of the mutational decay of their genomes through genetic drift or to selfish mutations that favor symbiont fitness over host fitness. One model for heritable endosymbiosis is the association of aphids with their obligate bacterial symbiont, We experimentally established heteroplasmic pea aphid matrilines containing pairs of closely related haplotypes and used deep sequencing of diagnostic markers to measure haplotype frequencies in successive host generations.
View Article and Find Full Text PDFMany insects possess beneficial bacterial symbionts that occupy specialized host cells and are maternally transmitted. As a consequence of their host-restricted lifestyle, these symbionts often possess reduced genomes and cannot be cultured outside hosts, limiting their study. The bacterial species was originally characterized as noncultured strains that live as mutualistic symbionts of aphids and are vertically transmitted through transovarial endocytosis within the mother's body.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2019
Bees acquire carbohydrates from nectar and lipids; and amino acids from pollen, which also contains polysaccharides including cellulose, hemicellulose, and pectin. These potential energy sources could be degraded and fermented through microbial enzymatic activity, resulting in short chain fatty acids available to hosts. However, the contributions of individual microbiota members to polysaccharide digestion have remained unclear.
View Article and Find Full Text PDFProbiotics are bacterial species or assemblages that are applied to animals and plants with the intention of altering the microbiome in a beneficial way. Probiotics have been linked to positive health effects such as faster disease recovery times in humans and increased weight gain in poultry. Pigeon fanciers often feed their show pigeons probiotics with the intention of increasing flight performance.
View Article and Find Full Text PDFThe ecological specialization of parasites-whether they can obtain high fitness on very few or very many different host species-is a determining feature of their ecology. In order to properly assess specialization, it is imperative to measure parasite fitness across host species; to understand its origins, fitness must be decomposed into the underlying traits. Despite the omnipresence of parasites with multiple hosts, very few studies assess and decompose their specialization in this way.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
July 2018
The pollution of ground and surface waters with pesticides is a serious ecological issue that requires adequate treatment. Most of the existing water pollution models are mechanistic mathematical models. While they have made a significant contribution to understanding the transfer processes, they face the problem of validation because of their complexity, the user subjectivity in their parameterization, and the lack of empirical data for validation.
View Article and Find Full Text PDFLeukemia inhibitory factor (LIF) is a cytokine that exhibits proliferative, survival and differentiation activities on a wide range of cell types. A role for LIF in embryonic development is suggested by: i) its ability to stimulate the proliferation of embryonic stem (ES) cells in vitro, while maintaining their totipotency and ii) by both its maternal and embryonic expression at the time of blastocyst implantation. Functional studies of LIF and its receptor during mouse embryogenesis have been performed using the techniques of targeted gene replacement and transgene expression in ES cells to produce transgenic mice bearing either loss- or gain-of-function mutations for LIF activity.
View Article and Find Full Text PDFLeukemia inhibitory factor (LIF; also known as cholinergic differentiation factor) is a multifunctional cytokine that affects neurons, as well as many other cell types. To examine its neuronal functions in vivo, we have used LIF-deficient mice. In culture, LIF alters the transmitter phenotype of sympathetic neurons, inducing cholinergic function, reducing noradrenergic function, and altering neuropeptide expression.
View Article and Find Full Text PDFLeukaemia inhibitory factor (LIF) has a variety of effects on different cell types in vitro, inhibiting the differentiation of embryonic stem cells and promoting the survival and/or proliferation of primitive haematopoietic precursors and primordial germ cells. Here we show that LIF-deficient mice derived by gene targeting techniques have dramatically decreased numbers of stem cells in spleen and bone marrow. Injection of spleen and marrow cells from these mice promotes long-term survival of lethally irradiated wild-type animals, however, showing that the LIF- stem cells remain pluripotent.
View Article and Find Full Text PDFWe have previously reported the identification and isolation by mRNA selection/translation of a recombinant clone containing 80% of the human vimentin gene sequence [Lilienbaum et al., EMBO J. 5 (1986) 2809-2814].
View Article and Find Full Text PDFArch Anat Cytol Pathol
July 1985
Proc Natl Acad Sci U S A
January 1982
Monoclonal IgMs from two patients with Waldenström macroglobulinemia were found to react with intermediate filaments. This was shown by (a) immunostaining of various tissues and cultured cells and (b) immunological characterization of the reactive antigen after blotting of polypeptides separated from total cell extracts by gel electrophoresis or purified intermediate filaments on nitrocellulose sheets. One monoclonal IgM had an activity directed only against vimentin, whereas the other reacted with four different classes of intermediate filaments--vimentin, desmin, glial fibrillary protein, and keratins.
View Article and Find Full Text PDFHexamethylene bisacetamide (HMBA) induces in vitro the cytodifferentiation of PCC3/A/1 mouse embryonal carcinoma (EC) cells. In EC cells, actin is associated with surface structures but microfilament bundles are not seen. After 2 days of HMBA treatment, rounded EC cells are converted to flat adhesive ones with a developed cytoskeleton containing actin and tropomyosin.
View Article and Find Full Text PDFAnn Microbiol (Paris)
January 1979
A thermosensitive mutant (ts-3) of polyoma virus produces T antigen, viral DNA and V antigen in BalbC/3T3 cells only at the permissive temperature (31 degrees C). At the non-permissive temperature (39 degrees C) these cells are unable to complement the viral defect. The pulse technique reveals only transitory cellular DNA induction between 15 and 25 h after infection at 39 degrees C.
View Article and Find Full Text PDFA broad-spectrum antiserum has been obtained against nuclear proteins from normal mouse fibroblasts. Solid phase immunoadsorbants prepared from the serum specifically bind the corresponding antigens. The removal in this way of a significant fraction of host proteins leads to partial purification of viral and virus-induced polypeptides from polyoma virus-infected cell extracts.
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