Abstract:
:A synchrotron radiation fiber diffraction structural study of the axial filament of siliceous spicules from two species of marine sponges (the Demosponge Geodia cydonium and the Hexactinellid Scolymastra joubini) was carried out. The sharpness of the spots in the diffraction patterns indicated that the protein units in the filament of both samples were highly organized. A possible explanation is that the arrangement of the protein units is similar to that of the pores in highly ordered siliceous mesoporous materials. Nevertheless, the diffraction patterns are quite different for the two types of spicules. The pattern of G. cydonium is consistent with a regular 2D hexagonal lattice of protein units in the direction perpendicular to the spicule axis, with a repeating distance of 5.8 nm; the units are linked to form fibers along the axis. The pattern of S. joubini indicates the presence of two different 2D lattices in which the repeating protein units are inclined by +50 degrees and -50 degrees with respect to the elongation axis; the distance between the units increases to 8.4 nm. This 2D model is consistent with hexagonal packing of spirally oriented cylindrical protein units elongated along the filament axis.
journal_name
Microsc Res Techjournal_title
Microscopy research and techniqueauthors
Croce G,Frache A,Milanesio M,Viterbo D,Bavestrello G,Benatti U,Giovine M,Amenitsch Hdoi
10.1002/jemt.10403keywords:
subject
Has Abstractpub_date
2003-11-01 00:00:00pages
378-81issue
4eissn
1059-910Xissn
1097-0029journal_volume
62pub_type
杂志文章abstract::This review article focuses on the ontogeny and the regulatory mechanisms involved in the modulation of the intracellular events governing the assembly and delivery of lipoproteins in human gut. The human fetal intestine organizes villi covered with well-differentiated enterocytes during the end of the first trimester...
journal_title:Microscopy research and technique
pub_type: 杂志文章,评审
doi:10.1002/(SICI)1097-0029(20000515)49:4<363::AID-JEM
更新日期:2000-05-15 00:00:00
abstract::This study was designed to investigate patterns of fibrils organization in histochemically stained otoconia. Transmission electron microscope and video imaging were used. These data indicate that otoconia of the chick (Gallus domesticus) inner ear may have central cores in vivo. The data also show that the ultrastruct...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.1070250406
更新日期:1993-07-01 00:00:00
abstract::Several models for preparing and isolating human and animal gallbladder epithelial cells, including low-grade gallbladder carcinoma cells, as well as proposed systems for culturing these isolated epithelial cells are reviewed here. Several reports concerning tissue culture of the gallbladder are also reviewed. The cel...
journal_title:Microscopy research and technique
pub_type: 杂志文章,评审
doi:10.1002/(SICI)1097-0029(19971001)39:1<71::AID-JEMT
更新日期:1997-10-01 00:00:00
abstract::The preparation of optically clear, thick sections of fragile embryonic tissues greatly aids the power of confocal scanning laser microscopy in imaging three-dimensional structures. We report here conditions for embedding, sectioning, and staining embryos in polyacrylamide gels for a variety of confocal imaging techni...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.1070300608
更新日期:1995-04-15 00:00:00
abstract::Assessment of HER2/neu oncogene has been used as both a prognostic and predictive marker for breast cancer. However, the choice of the best method to assess the status of HER2/neu oncogene in breast cancer tissue remains controversial. A variety of techniques are available to detect HER2/neu gene amplification and ove...
journal_title:Microscopy research and technique
pub_type: 杂志文章,评审
doi:10.1002/jemt.10181
更新日期:2002-10-15 00:00:00
abstract::The research was performed to investigate pollen morphology of endangered species of Capparidaceae in subtropical regions of Pakistan. The distinguishing characters were investigated by using light microscope and scanning electron microscope. Palynological study is comprised of pollen shape, pollen type, exine sculptu...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.23292
更新日期:2019-09-01 00:00:00
abstract::Among the various corrosion protection strategies for structural steels, coating techniques provide the most cost-effective protection and have been used as the primary mode of corrosion protection. Existing coating techniques however have been used mainly for their barrier capability and therefore all have a limited ...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.22283
更新日期:2013-11-01 00:00:00
abstract::Vanda tessellata (Roxb.) Hook. ex G. Don. (grey orchid, family Orchidaceae) is an epiphytic orchid of horticultural importance and currently under threat due to overharvesting and habitat destruction. Micropropagation protocols were developed for the production of grey orchid but the survival success of in vitro regen...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.23630
更新日期:2020-10-22 00:00:00
abstract::Progressive multifocal leukoencephalopathy is an important viral opportunistic infection of oligodendrocytes leading to direct demyelination. Virus is likely disseminated to the brain via the blood. However, the timing of that dissemination with relationship to clinical disease is unknown. Important clues about viral ...
journal_title:Microscopy research and technique
pub_type: 杂志文章,评审
doi:10.1002/jemt.1070320405
更新日期:1995-11-01 00:00:00
abstract::The fine structure of human oogonia and growing oocytes has been reviewed in fetal and adult ovaries. Preovulatory maturation and the ultrastructure of stimulated oocytes from the germinal vesicle (GV) stage to metaphase II (MII) stage are also documented. Oogonia have large nuclei, scanty cytoplasm with complex mitoc...
journal_title:Microscopy research and technique
pub_type: 杂志文章,评审
doi:10.1002/jemt.20299
更新日期:2006-06-01 00:00:00
abstract::Sensory mechanisms in teeth are not well understood and may involve pulpal-neural interactions. Tooth cells that proliferate in vitro have polyclonal immunoreactivity (IR) for glial fibrillary acidic protein (GFAP), growth-associated protein (GAP-43), and vimentin, plus glial-like ion channels. Here, we analyzed GFAP-...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.20130
更新日期:2004-12-01 00:00:00
abstract::Atomic force microscopy has been used to study self-assembled structures of two alpha-hemolysin mutants. For a mutant (alphaHL-H5) that was locked into the prepore state on fluid phase egg-PC membranes, we visualized, for the first time, heptameric prepores and showed that the 7-fold axis in the prepore lies perpendic...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0029(19990301)44:5<353::AID-JEM
更新日期:1999-03-01 00:00:00
abstract::This article presents an integrated approach for the authentication of five Russian icons through the study of their paint materials (elemental composition and stratigraphic mapping), state of conservation and artistic technique. The results of the applied analytical protocol, involving optical and scanning electron m...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.20727
更新日期:2009-10-01 00:00:00
abstract::Because of the increasing medical-veterinary importance of ticks, the development of alternative control methods, less aggressive to the host and the environment has become the target of several researches. In this sense, the present study analyzed the action of different concentrations (5, 10, and 20%) of andiroba se...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.22126
更新日期:2012-12-01 00:00:00
abstract::In the search for a new methodological approach applicable to the determination of the still poorly known primary role of boron in plant physiology, we have undertaken to appraise the potential of the SIMS method for the analytical imaging of the boron isotopes, (10)B and (11)B, at physiological concentrations in plan...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.10125
更新日期:2002-07-15 00:00:00
abstract::A major challenge when performing scanning electron microscopy and X-ray analysis on many ceramic materials is their electrical insulation properties, which leads to buildup of the surface charge and reduced contrast in the secondary electron image. A new procedure was established to quantitatively determine the neutr...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.23118
更新日期:2018-10-01 00:00:00
abstract::Automated detection and classification of gastric infections (i.e., ulcer, polyp, esophagitis, and bleeding) through wireless capsule endoscopy (WCE) is still a key challenge. Doctors can identify these endoscopic diseases by using the computer-aided diagnostic (CAD) systems. In this article, a new fully automated sys...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.23447
更新日期:2020-05-01 00:00:00
abstract:BACKGROUND:Ultrasonic excitation (US) was applied to glass ionomer cement (GIC) during early set time to increase the advantageous properties of this material. PURPOSE:The aim of this in vitro study was to assess the inner porosity of GIC after US. STUDY DESIGN:A total of 16 specimens, for each material, were prepare...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.20873
更新日期:2011-01-01 00:00:00
abstract::The energy resolution of an energy dispersive spectrometer (EDS) equipped with an ultrathin window (UTW) and mounted at a high take-off angle (72 degrees) on a transmission electron microscope has been studied under a variety of operating conditions. The spectrometer resolution is close to that specified by the manufa...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.1070220208
更新日期:1992-07-01 00:00:00
abstract::The aim of this report was to investigate the ultrastructure and three-dimensional organization of the pleural lymphatic stomata in the adult rabbit costal pleura by electron microscopy. A computer image processing system attached to the scanning electron microscopy was used to get statistical evaluation of the dimens...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.10388
更新日期:2003-10-15 00:00:00
abstract::The antennal flagellum of female Manduca sexta bears eight sensillum types: two trichoid, two basiconic, one auriculate, two coeloconic, and one styliform complex sensilla. The first type of trichoid sensillum averages 34 microm in length and is innervated by two sensory cells. The second type averages 26 microm in le...
journal_title:Microscopy research and technique
pub_type: 杂志文章,评审
doi:10.1002/jemt.1180
更新日期:2001-12-01 00:00:00
abstract::We have used high voltage electron microscopy and computer-generated three-dimensional reconstructions from serial sections to elucidate the structure of taste bud cells and their associated synapses in fungiform taste buds of the mouse. Five fungiform taste buds (two of which were serially sectioned) were examined wi...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.1070260207
更新日期:1993-10-01 00:00:00
abstract::This report describes osteoclastic bone resorption around intraosseous fixation screws in rat and pig mandibles. These screws supported distraction devices and provided for neutral fixation following the distraction period. Progressive clinical instability of bicortical screws and radiographic and histologic evidence ...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.10376
更新日期:2003-08-15 00:00:00
abstract::Research into the POU transcription factor Oct-6 has been the focus of much current attention, in particular its role in Schwann cell development and differentiation. Based on published data and data presented here, we propose a model for Oct-6 function at two distinct stages of Schwann cell maturation. First, Oct-6 f...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0029(19980601)41:5<372::AID-JEM
更新日期:1998-06-01 00:00:00
abstract::Magnetotactic bacteria orient and migrate along geomagnetic field lines. Each cell contains membrane-enclosed, nano-scale, iron-mineral particles called magnetosomes that cause alignment of the cell in the geomagnetic field as the bacteria swim propelled by flagella. In this work we studied the ultrastructure of the f...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.20380
更新日期:2007-01-01 00:00:00
abstract::Voltage-gated sodium channels are largely localized to the nodes of Ranvier in myelinated axons, providing the physiological basis for saltatory conduction. Studies using antisodium channel antibodies have shown that along demyelinated axons sodium channels form new distributions. The nature of this changed distributi...
journal_title:Microscopy research and technique
pub_type: 杂志文章,评审
doi:10.1002/(SICI)1097-0029(19960801)34:5<445::AID-JEM
更新日期:1996-08-01 00:00:00
abstract::A homemade colloidal probe atomic force microscope was used to perform nanoindentation with a spherical probe of 5 microm in diameter, at different approach velocities in order to extract the Young's modulus, E0, of poly(L-lysine)/hyaluronan (PLL/HA) films. This parameter is of prime importance to control cellular adh...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.20275
更新日期:2006-02-01 00:00:00
abstract::In conventional whole-tooth culture systems, limitation exists regarding maintenance of the vitality of the dental pulp, because this tissue is encased in rigid dentin walls that hinder nutrition supply. We here report a whole tooth-in-jaw-bone culture system of rat mandibular first molars, where transcardiac perfusio...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.22072
更新日期:2012-10-01 00:00:00
abstract::Pituitary-derived factors, including ACTH, have been widely implicated in initiating adrenal regeneration. However, recent work has demonstrated that adrenal regeneration is also modulated by adrenal nerves that extensively reinnervate the regenerating adrenal. Moreover, transection of the splanchnic nerve removes sen...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.10334
更新日期:2003-06-15 00:00:00
abstract::Although several treatments for tendon lesions have been proposed, successful tendon repair remains a great challenge for orthopedics, especially considering the high incidence of re-rupture of injured tendons. Our aim was to evaluate the pharmacological potential of Aloe vera on the content and arrangement of glycosa...
journal_title:Microscopy research and technique
pub_type: 杂志文章
doi:10.1002/jemt.22422
更新日期:2014-12-01 00:00:00