Search results for "Histology"

Beyond the functional matrix hypothesis: a network null model of human skull growth for the formation of bone articulations.

2014

Craniofacial sutures and synchondroses form the boundaries among bones in the human skull, providing functional, developmental and evolutionary information. Bone articulations in the skull arise due to interactions between genetic regulatory mechanisms and epigenetic factors such as functional matrices (soft tissues and cranial cavities), which mediate bone growth. These matrices are largely acknowledged for their influence on shaping the bones of the skull; however, it is not fully understood to what extent functional matrices mediate the formation of bone articulations. Aiming to identify whether or not functional matrices are key developmental factors guiding the formation of bone articu…

Bioactive and biodegradable silica biomaterial for bone regeneration.

2014

Biosilica, a biocompatible, natural inorganic polymer that is formed by an enzymatic, silicatein-mediated reaction in siliceous sponges to build up their inorganic skeleton, has been shown to be morphogenetically active and to induce mineralization of human osteoblast-like cells (SaOS-2) in vitro. In the present study, we prepared beads (microspheres) by encapsulation of β-tricalcium phosphate [β-TCP], either alone (control) or supplemented with silica or silicatein, into the biodegradable copolymer poly(d,l-lactide-co-glycolide) [PLGA]. Under the conditions used, ≈5% β-TCP, ≈9% silica, and 0.32μg/mg of silicatein were entrapped into the PLGA microspheres (diameter≈800μm). Determination of …

Prolonged breastfeeding is associated with greater bone size and bone strength

2011

Orientational analysis of planar fibre systems observed as a Poisson shot-noise process

2007

Summary We consider two-dimensional fibrous materials observed as a digital greyscale image. The problem addressed is to estimate the orientation distribution of unobservable thin fibres from a greyscale image modelled by a planar Poisson shot-noise process. The classical stereological approach is not straightforward, because the point intensities of thin fibres along sampling lines may not be observable. For such cases, Karkkainen et al. (2001) suggested the use of scaled variograms determined from grey values along sampling lines in several directions. Their method is based on the assumption that the proportion between the scaled variograms and point intensities in all directions of sampl…

Comparative electronmicroscopic studies on the central cardiac organs of cephalopods (Sepia officinalis)

1969

Die Untersuchungen zur Feinstruktur des Herzens von Sepia officinalis zeigen fur die quer- bzw. schraggestreifte Muskulatur dieses Organs einen hohen Differenzierungsgrad auf. 1. Die Sarkomeren werden mit dem Auftreten zweier Filamenttypen wie die quergestreifte Vertebratenmuskulatur in Z-, A- und I-Bande gegliedert, wobei jedoch die Z-Bande aus einzelnen Teilelementen besteht. 2. Die Herzmuskulatur der Cephalopoden verfugt uber Strukturen, die in Analogie zum Vertebratenherzen als Disci intercalares bezeichnet werden. 3. eben einem langs und quer verlaufenden sarkotubularen System wird die Existenz eines mit dem Ausenraum kommunizierenden T-Systems nachgewiesen. Beide Systeme stehen uber M…

Specific Identification and Quantification of the Spoilage Microorganism Brettanomyces in Wine by Flow Cytometry: A Useful Tool for Winemakers

2010

International audience; no abstract

Distribution patterns of neoglycoprotein-binding sites (endogenous lectins) and lectin-reactive glycoconjugates during cartilage and bone formation i…

1995

The distribution of endogenous lectins, visualized by labelled neoglycoproteins, and of defined oligosaccharide structures, reactive with plant lectins, during fetal development of the fingers was analyzed in sections of human 3- to 8-month-old fetal specimens. Chondrogenesis as well as ossification were correlated with characteristic modulations in the expression of both glycoligand-binding molecules and characteristic carbohydrate structures. Occurrence of xylose-specific receptors was judged to be an early sign of cartilage development. Similarly, α-mannosyl residues that had been attached to labelled carrier proteins were strongly bound by the extracellular matrix already during early s…

Autophagy, cathepsin L transport, and acidification in cultured rat fibroblasts.

1992

The mechanisms of enzyme delivery to and acidification of early autophagic vacuoles in cultured fibroblasts were elucidated by cryoimmunoelectron microscopic methods. The cation-independent mannose-6-phosphate receptor (MPR) was used as a marker of the pre-lysosomal compartment, and cathepsin L and an acidotropic amine (3-(2,4-dinitroanilino)-3'-amino-N-methyl-dipropylamine (DAMP), a cytochemical probe for low-pH organelles) as markers of both pre-lysosomal and lysosomal compartments. In addition, cationized ferritin was used as an endocytic marker. In ultrastructural double labeling experiments, the bulk of all the antigens was found in vesicles containing tightly packed membrane material…

Die Prothorakaldr�sen der Larve vonTenebrio molitor L. (Tenebrionidae, Coleoptera) und ihre Ver�nderungen w�hrend eines H�utungszyklus

1971

1. Die Ecdysialdrusen der Larve vonTenebrio liegen in 2 Bandern entlang der dorsalen Tracheenaste und deren Verzweigungen im Prothorax. 2. Mit histochemischen Methoden konnten in den Drusenzellen Glykogen, Cholesterin und Lipidtropfchen nachgewiesen werden. Versuche mit tritiummarkiertem Cholesterin zeigten, das dieses mit den Lipidtropfchen in die Zellen der Prothorakaldrusen gelangt. 3. Mit Hilfe der Methylenblaufarbung wurde eine Innervation der Prothorakaldrusen nachgewiesen, die vom Unterschlund- und vom Prothoraxganglion ausgeht. Elektronenmikroskopisch konnten Neurosekretgranula in Axonen, die in die Basalmembran und z. T. durch die Drusenzellen selbst ziehen, nachgewiesen werden. 4.…

�ber das Ligamentum pectinatum der Primaten

1962

Die Kammerwinkelregion des Auges 25 verschiedener Primatenarten wurde licht- und teilweise elektronenmikroskopisch untersucht. Bei Tupaia, Lemuriformes und Lorisiformes ist ein kraftiges Lig. pectinatum und eine tiefe Kammerbucht mit einem relativ undifferenzierten Filterwerk entwickelt, wahrend bei den Simiae allgemein ein hochdifferenziertes Trabekelwerk, sowie umgekehrt ein rudimentares Lig. pectinatum zu beobachten ist. Das Trabekelwerk der Simiae stellt allgemein ein lamellenartig geordnetes, mucopolysaccharidreiches, quasi „hypertrophiertes“ Basalmembransystem mit kollagenen und elastischen Fasern, sowie eigenartigen „kollagenoiden“ Strukturen mit einer Querperiode von etwa 1000 A (so…