Search results for "Microscopy"
showing 10 items of 3390 documents
Vector Transmission of a Plant-Pathogenic Bacterium in the Arsenophonus Clade Sharing Ecological Traits with Facultative Insect Endosymbionts
2009
Bressan, A., Semetey, O., Arneodo, J., Lherminier, J., and BoudonPadieu, E. 2009. Vector transmission of a plant-pathogenic bacterium in the Arsenophonus clade sharing ecological traits with facultative insect endosymbionts. Phytopathology 99:1289-1296. The planthopper Pentastiridius leporinus (Hemiptera: Cixiidae) is the major vector of a nonculturable plant-pathogenic γ-3 proteobacterium associated with a disease of sugar beet called syndrome “basses richesses” (SBR). The bacterium, here called SBR bacterium, belongs to the Arsenophonous clade, which includes mostly insect-associated facultative symbionts. Assays using field-collected planthopper nymphs and adults were carried out to inve…
Parvalbumin-containing interneurons do not innervate granule cells in the olfactory bulb
2001
Combining pre-embedding parvalbumin immunostaining and post-embedding immunogold detection of GABA in the olfactory bulb, we investigated whether the parvalbumin-containing GABAergic interneurons of the external plexiform layer exclusively innervate principal cells, or whether they also establish inhibitory synapses upon GABAergic local neurons such as granule cells. Our results demonstrate that the parvalbumin-containing cells do not contact GABAergic interneurons in the neuropil of the external plexiform layer. On the contrary, their postsynaptic elements were always non-GABAergic principal cells. Although classically it has been accepted that the interneurons of the external plexiform la…
Ultraviolet vision in lacertid lizards: evidence from retinal structure, eye transmittance, SWS1 visual pigment genes, and behaviour
2014
Abstract Ultraviolet (UV) vision and UV colour patches have been reported in a wide range of taxa and are increasingly appreciated as an integral part of vertebrate visual perception and communication systems. Previous studies with Lacertidae, a lizard family with diverse and complex coloration, have revealed the existence of UV-reflecting patches that may function as social signals. However, confirmation of the signalling role of UV coloration requires demonstrating that the lizards are capable of vision in the UV waveband. Here we use a multidisciplinary approach to characterize the visual sensitivity of a diverse sample of lacertid species. Spectral transmission measurements of the ocula…
Studies on vinblastine-induced autophagocytosis in mouse liver
1980
The origin of the membranes of autophagic vacuoles (AV) and acquisition of acid phosphatase into AV's were studied in vinblastine-induced autophagocytosis (VBL, 50 mg/kg, i.p.) in mouse hepatocytes. Using unbuffered OsO4, very intense staining was observed in the outer cisternae of the Golgi apparatus and also frequently in the cavity between the double membranes obviously destined to form AV's as well as in the cavity between the double membranes of newly formed AV's. There may occur a transformation process in the membranes limiting an AV analogous to that observed at the Golgi cisternae. The transformation of the outer AV membrane occurs independently of fusion with lysosomes. Inosine di…
Rapid palatal expansion: the role of microcirculation
2015
Transverse palate modifications fall under expansive orthopedic therapy of the upper maxilla. The only practical approach to the problem on the transverse plane is that of performing the expansion of the maxillary arch through an opening of the median palatal suture. It is important to understand the changes of the vascular network in midpalatal suture following the starting of rapid maxillary expansion. It is critical to maintain the blood supply and circulation for the osteogenesis and bone remodeling after the expansion. The aim of this research was to evaluate the effects of rapid orthopedic expansion (REP) at the microcirculatory level through capillaroscopic examination. METHODS: Fift…
Convergence of Cortical and Sensory Driver Inputs on Single Thalamocortical Cells
2013
Ascending and descending information is relayed through the thalamus via strong, "driver" pathways. According to our current knowledge, different driver pathways are organized in parallel streams and do not interact at the thalamic level. Using an electron microscopic approach combined with optogenetics and in vivo physiology, we examined whether driver inputs arising from different sources can interact at single thalamocortical cells in the rodent somatosensory thalamus (nucleus posterior, POm). Both the anatomical and the physiological data demonstrated that ascending driver inputs from the brainstem and descending driver inputs from cortical layer 5 pyramidal neurons converge and interac…
Optical release of caged glutamate for stimulation of neurons in the in vitro slice preparation
2005
Optical stimulation techniques prove useful to map func- tional inputs in the in vitro brain slice preparation: Glutamate released by a focused beam of UV light induces action potentials, which can be detected in postsynaptic neurons. The direct activation effect is influenced by factors such as compound concentration, focus depth, light absorption in the tissue, and sensitivity of different neuronal do- mains. We analyze information derived from direct stimulation ex- periments in slices from rat barrel cortex and construct a computa- tional model of a layer V pyramidal neuron that reproduces the experimental findings. The model predictions concerning the influ- ence of focus depth on inpu…
Difference in the expression of IL-9 and IL-17 correlates with different histological pattern of vascular wall injury in giant cell arteritis
2015
OBJECTIVE: GCA is a large- and medium-vessel arteritis characterized by a range of histological patterns of vascular wall injury. The aim of this study was to immunologically characterize the various histological patterns of GCA. METHODS: Thirty-five consecutive patients with biopsy-proven GCA and 15 normal controls were studied. IL-8, IL-9, IL-9R, IL-17, IL-4, TGF-β and thymic stromal lymphopoietin expression was evaluated by RT-PCR and immunohistochemistry on artery biopsy specimens. Confocal microscopy was used to characterize the phenotypes of IL-9-producing and IL-9R-expressing cells. Five additional patients who had received prednisone when the temporal artery biopsy was performed wer…
Unusual B cell morphology in inflammatory bowel disease.
2012
B lymphocytes express various different types of surface immunoglobulins that are largely unrelated to other hematological lines, although some reports have described a relationship between malignant B cells and other cells such as macrophages. Multiple genes of hematopoietic lineage, including transcription factors, are co-expressed in hematopoietic stem cells and progenitors, a phenomenon referred to as "lineage priming". Changes in the expression levels and timing of transcription factors can induce the lineage conversion of committed cells, which indicates that the regulation of transcription factors might be particularly critical for maintaining hierarchical hematopoietic development. …
Expanding the clinical spectrum of hereditary fibrosing poikiloderma with tendon contractures, myopathy and pulmonary fibrosis due to FAM111B mutatio…
2015
Background Hereditary Fibrosing Poikiloderma (HFP) with tendon contractures, myopathy and pulmonary fibrosis (POIKTMP [MIM 615704]) is a very recently described entity of syndromic inherited poikiloderma. Previously by using whole exome sequencing in five families, we identified the causative gene, FAM111B (NM_198947.3), the function of which is still unknown. Our objective in this study was to better define the specific features of POIKTMP through a larger series of patients. Methods Clinical and molecular data of two families and eight independent sporadic cases, including six new cases, were collected. Results Key features consist of: (i) early-onset poikiloderma, hypotrichosis and hypoh…