A survey of the presence and morphology of orbicules in European allergenic angiosperms. Background information for allergen research

2001 ◽  
Vol 79 (7) ◽  
pp. 757-766 ◽  
Author(s):  
Stefan Vinckier ◽  
Erik Smets
Keyword(s):  
Atmospheric Aerosol ◽  
Size Range ◽  
Background Information ◽  
Allergic Reactions ◽  
Small Particles ◽  
Allergenic Plants ◽  
Tangential Wall ◽  
Allergenic Activity ◽  
Almost All ◽  
Scanning Electron

Allergenic activity in the atmospheric aerosol of small particles in the size range of a few micrometres or less may play an important role in causing allergic reactions in the lower regions of the lungs, often seen in pollinosis. Orbicules (= Ubisch bodies) are small, mostly spherical granules of sporopollenin, which can occur on the radial and innermost tangential wall of secretory tapetum cells. In instances where orbicules of allergenic species are dispersed into the atmosphere, they may act as effective vectors of allergens. We investigated the presence and morphology of orbicules in 15 allergenic species using scanning electron microscopy. Orbicules were present in all species investigated of the families Betulaceae, Chenopodiaceae, Fagaceae, Poaceae, Polygonaceae, and Urticaceae. In the species of the Asteraceae and Oleaceae studied, orbicules were lacking. Almost all orbicules observed were spiny. Their mean diameters range from 0.342 to 1.130 μm. Orbicules can be part of the fraction of small particles in the size range of a few micrometres or less, emitted from the anthers. Our results clearly indicate that a thorough investigation of the sites of allergens across the whole anther is required to reveal whether or not these orbicules possess allergens.Key words: allergenic plants, allergen research, morphology, orbicules.

Dynamic Scanning Electron Microscopy of Small Particles

1975 ◽  
Vol 33 ◽  
pp. 280-281
Author(s):  
W. Krakow ◽  
W. C. Nixon
Keyword(s):  
Electron Microscopy ◽  
Low Noise ◽  
Time Sequence ◽  
Field Of View ◽  
Video Tape ◽  
Small Particles ◽  
Polystyrene Spheres ◽  
Field Distributions ◽  
Dynamic Scanning ◽  
Scanning Electron

The scanning electron microscope (SEM) can be run at television scanning rates and used with a video tape recorder to observe dynamic specimen changes. With a conventional tungsten source, a low noise TV image is obtained with a field of view sufficient to cover the area of the specimen to be recorded. Contrast and resolution considerations have been elucidated and many changing specimens have been studied at TV rates.To extend the work on measuring the magnitude of charge and field distributions of small particles in the SEM, we have investigated their motion and electrostatic interaction at TV rates. Fig. 1 shows a time sequence of polystyrene spheres on a conducting grating surface inclined to the microscope axis. In (la) there are four particles present in the field of view, while in (lb) a fifth particle has moved into view.

Scanning electron microscopy of composite hydroxylapatite/plaster implants for bone reconstruction

1986 ◽  
Vol 44 ◽  
pp. 326-327
Author(s):  
J. S. Hanker ◽  
B. L. Giammara
Keyword(s):  
Tooth Extraction ◽  
Alveolar Ridge ◽  
Small Particles ◽  
Alveolar Ridge Augmentation ◽  
Sintered Ceramic ◽  
Ridge Augmentation ◽  
Fibrovascular Tissue ◽  
Infrabony Defects ◽  
Edentulous Patients ◽  
Scanning Electron

Nonresorbable sintered ceramic hydroxylapatite (HA) is widely employed for filling defects in jaw bone. The small particles used for alveolar ridge augmentation in edentulous patients or for infrabony defects due to periodontal disease tend to scatter when implanted using water or saline as the vehicle. Larger blocks of this material used for filling sockets after tooth extraction don't fit well. Studies in our laboratory where we compared bovine serum albumin, collagen and plaster of Paris as binders to prevent particle scatter during implantation suggested that plaster was most useful for this purpose. In addition to preventing scatter of the particles, plaster enables the formation of implants of any size and.shape either prior to or during surgery. Studies with the PATS reaction have indicated that plaster acts as a scaffold for the incorporation of HA particles into bone in areas where the implant contacts either host bone or periosteum. The shape and integrity of the implant is maintained by the plaster component until it is replaced over a period of days by fibrovascular tissue.

High-resolution scanning electron microscopy in biology

1990 ◽  
Vol 48 (3) ◽  
pp. 14-15
Author(s):  
Keiichi Tanaka
Keyword(s):  
High Resolution ◽  
Immunoglobulin M ◽  
Metal Coating ◽  
Biological Macromolecules ◽  
Ultrahigh Resolution ◽  
Preparation Methods ◽  
Low Contrast ◽  
Almost All ◽  
Charging Effect ◽  
Scanning Electron

With the development of scanning electron microscope (SEM) with ultrahigh resolution, SEM became to play an important role in not only cytology but also molecular biology. However, the preparation methods observing tiny specimens with such high resolution SEM are not yet established.Although SEM specimens are usually coated with metals for getting electrical conductivity, it is desirable to avoid the metal coating for high resolution SEM, because the coating seriously affects resolution at this level, unless special coating techniques are used. For avoiding charging effect without metal coating, we previously reported a method in which polished carbon plates were used as substrate. In the case almost all incident electrons penetrate through the specimens and do not accumulate in them, when the specimens are smaller than 10nm. By this technique some biological macromolecules including ribosomes, ferritin, immunoglobulin G were clearly observed.Unfortunately some other molecules such as apoferritin, thyroglobulin and immunoglobulin M were difficult to be observed only by the method, because they had very low contrast and were easily damaged by electron beam.

scholarly journals Synthesis and Evaluation of AlgNa-g-poly(QCL-co-HEMA) Hydrogels as Platform for Chondrocyte Proliferation and Controlled Release of Betamethasone

2021 ◽  
Vol 22 (11) ◽  
pp. 5730
Author(s):  
Jomarien García-Couce ◽  
Marioly Vernhes ◽  
Nancy Bada ◽  
Lissette Agüero ◽  
Oscar Valdés ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Controlled Release ◽  
Biomedical Applications ◽  
Release Kinetics ◽  
Cell Types ◽  
Tissue Engineering Scaffolds ◽  
Almost All ◽  
Scanning Electron

Hydrogels obtained from combining different polymers are an interesting strategy for developing controlled release system platforms and tissue engineering scaffolds. In this study, the applicability of sodium alginate-g-(QCL-co-HEMA) hydrogels for these biomedical applications was evaluated. Hydrogels were synthesized by free-radical polymerization using a different concentration of the components. The hydrogels were characterized by Fourier transform-infrared spectroscopy, scanning electron microscopy, and a swelling degree. Betamethasone release as well as the in vitro cytocompatibility with chondrocytes and fibroblast cells were also evaluated. Scanning electron microscopy confirmed the porous surface morphology of the hydrogels in all cases. The swelling percent was determined at a different pH and was observed to be pH-sensitive. The controlled release behavior of betamethasone from the matrices was investigated in PBS media (pH = 7.4) and the drug was released in a controlled manner for up to 8 h. Human chondrocytes and fibroblasts were cultured on the hydrogels. The MTS assay showed that almost all hydrogels are cytocompatibles and an increase of proliferation in both cell types after one week of incubation was observed by the Live/Dead® assay. These results demonstrate that these hydrogels are attractive materials for pharmaceutical and biomedical applications due to their characteristics, their release kinetics, and biocompatibility.

ALLERGENIC ACTIVITY AND DANGER OF INDUSTRIAL DUSTS OF DRY PRODUCTS OF COW'S MILK PROCESSING

2021 ◽  
pp. 51-55
Author(s):  
Baranov S.A. ◽  
◽  
Shevlyakov V.V. ◽  
Sychyk S.I. ◽  
Filonyuk V.A. ◽  
...  
Keyword(s):  
Milk Proteins ◽  
The Body ◽  
Cow’S Milk ◽  
Antigenic Determinants ◽  
Allergic Reactions ◽  
Cow's Milk ◽  
Milk Processing ◽  
Allergenic Activity

The purpose of the work was to establish in a model experiment the allergenic activity and danger of the extracts obtained from the dust of dry products of cow's milk processing (DPMP), containing complexes of soluble whey (WMP) or casein milk proteins (CMP), as a stage of hygienic regulation of the content of dust DPMP in the air of the working area. Experiments on albino guinea pigs sensitized by the intradermal injection of standard doses of WMP and СМР solutions into the ear revealed the development of severe allergic reactions in the animals of the experimental groups with the prevalence of mixed mechanisms of immediate anaphylactic and delayed cell-mediated types. According to the criteria for the classification of industrial allergens, the WMP and СМР complexes have a strong allergenic activity and are differentiated to the 1-st class of allergenic hazard, which determines the classification of the DPMP dust containing them as extremely dangerous industrial allergens. This is confirmed by the established high levels of indicators of allergic-diagnostic reactions in vivo and in vitro when testing sensitized WMP and СМР animals with a solution of skim milk powder dust, indicating the presence of antigenic determinants of whey and casein milk proteins in it and a real ability to form cross-allergic reactions in the body of workers to dust from all dry milk processing products containing these proteins.

The Mechanism of active capture of animal food by the Sergestid Shrimp Acetes Sibogae Australis

1998 ◽  
Vol 78 (2) ◽  
pp. 497-508 ◽  
Author(s):  
Lachlan Mcleay ◽  
C.G. Alexander
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Prey Capture ◽  
Size Range ◽  
The Third ◽  
Feeding Modes ◽  
In Captivity ◽  
Combined Actions ◽  
Wide Size Range ◽  
Scanning Electron

Combining the use of scanning electron microscopy and microcinematography with functional and behavioural observations has clarified many aspects underlying the feeding processes of the small planktonic sergestid shrimp Acetes sibogae australis. In captivity Acetes sibogae australis is an opportunistic feeder that uses four principal feeding modes to capture a wide size range of prey: Artemia nauplii (<0.33 mm), copepods (<1mm) and moribund Acetes (up to 25 mm). Prey capture is effected by combined actions of the first three pairs of pereiopods and the third maxillipeds before transfer to the more dorsal second maxillipeds. The second maxillipeds are the principal appendages used in securing, manipulating, sorting and rejecting prey before insertion into the vicinity of the inner mouthparts.

Comparison of Wallace, Nixon, and Humphrey Supporters along Certain Demographic, Attitudinal, and Value-System Dimensions

1973 ◽  
Vol 32 (1) ◽  
pp. 35-39 ◽  
Author(s):  
James Rawls ◽  
C. Wade Harrison ◽  
Donna J. Rawls ◽  
Robert L. Hayes ◽  
August W. Johnson
Keyword(s):  
Church Attendance ◽  
Family Income ◽  
Social Recognition ◽  
Background Information ◽  
Stepwise Discriminant Analysis ◽  
Law And Order ◽  
Value System ◽  
Southern States ◽  
Registered Voters ◽  
Almost All

A 28-item questionnaire and the Rokeach Value Survey were administered to 298 registered voters in 12 Southern states. The questionnaire included (1) background information such as age, marital status, education, family income, church attendance, etc., and (2) attitudinal data such as Hawk-Dove, law and order, integration-segregation issues, etc. In addition, the 18 terminal values of the Rokeach scale were rank-ordered by all Ss. The data were first analyzed so as to describe Wallace, Nixon, and Humphrey supporters along demographic, attitudinal, and value-system dimensions. A stepwise discriminant analysis indicated that seven values accounted for almost all of the variance. In order of discriminatory power, these values are as follows: equality, national security, world of beauty, inner harmony, pleasure, social recognition, and family security.

Scanning electron microscopy of lattice organs in cyprids of the Rhizocephala Akentrogonida (Crustacea: Cirripedia)

1994 ◽  
Vol 72 (6) ◽  
pp. 1018-1026 ◽  
Author(s):  
Peter Gram Jensen ◽  
Jens T. Høeg ◽  
Susan Bower ◽  
Alexey V. Rybakov
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sister Group ◽  
Poor Quality ◽  
Sister Group Relationship ◽  
Sensory Structures ◽  
Lattice Organs ◽  
Almost All ◽  
Scanning Electron

The morphology and disposition of lattice organs, putative sensory structures in the carapace of cyprids, are described with scanning electron microscopy from six rhizocephalan species representing four of the five families in the suborder Akentrogonida: Clistosaccus paguri and Sylon hippolytes (Clistosaccidae), Arcturosaccus kussakini (Duplorbidae), Mycetomorpha vancouverensis (Mycetomorphidae), and Diplothylacus sinensis and Thylacoplethus reinhardi (Thompsoniidae). The disposition of pores and setae on the cyprid carapace is also surveyed. In T. reinhardi, poor quality of the specimens allowed only confirmation that lattice organs are present. Cyprids of all other species except M. vancouverensis have two anterior and three posterior pairs of lattice organs on the carapace, just as in almost all other Cirripedia. Cyprids of C. paguri and S. hippolytes are nearly identical in both general shape, carapace setation, and morphology of the lattice organs. In both species the lattice organs are oval–circular pore fields, except the second pair which is very elongate and match-shaped, a morphology unique to the Clistosaccidae. The similarities in cyprid morphology are interpreted as apomorphies supporting the monophyly of the recently rediagnosed Clistosaccidae. Both thompsoniid species have oval–circular lattice organs, indicating a possible sister-group relationship between the Clistosaccidae and the Thompsoniidae. None of the lattice organs of A. kussakini are oval or match-shaped. In M. vancouverensis there is only a single anterior pair of lattice organs, a probable autapomorphy. But the morphology of the M. vancouverensis cyprid is otherwise very reminiscent of those in the Rhizocephala suborder Kentrogonida, such as in being ornamented with numerous (> 100) carapace setae in no fixed pattern compared with the few (< 80) setae in a fixed disposition seen in the other akentrogonids. In cyprids of all Akentrogonida examined, the lattice organs lack a large terminal pore. By out-group comparison with all other cirripedes and with the Ascothoracida, this is regarded as an apomorphy that supports the monophyly of the Akentrogonida.

Behavioral roles of the sexually dimorphic structures in the male harvestman, Phalangium opilio (Opiliones, Phalangiidae)

2006 ◽  
Vol 84 (12) ◽  
pp. 1763-1774 ◽  
Author(s):  
Rodrigo H. Willemart ◽  
Jean-Pierre Farine ◽  
Alfredo V. Peretti ◽  
Pedro Gnaspini
Keyword(s):  
Electron Micrographs ◽  
Animal Species ◽  
Morphometric Study ◽  
Sexually Dimorphic ◽  
Scanning Electron Micrographs ◽  
Face To Face ◽  
Frequency Of Contact ◽  
Almost All ◽  
Male Contests ◽  
Scanning Electron

In various animal species, male sexual dimorphic characters may be used during intrasexual contests as ornaments to attract females, or to hold them before, during, or after copulation. In the well-known harvestman, Phalangium opilio L., 1758, the behavioral functions of these male sexually dimorphic structures have never been studied in detail. Therefore, in addition to a morphometric study, 21 male contests and 43 sexual interactions were analyzed. Our observations revealed that during contests, the male cheliceral horns form a surface by which the contestants use to push each other face-to-face while rapidly tapping their long pedipalps against the pedipalps of the opponent, occasionally twisting the opponent’s pedipalp. Scanning electron micrographs revealed contact mechanoreceptors on the pedipalp that would detect the intensity–frequency of contact with the contender’s pedipalp. Larger males won almost all contests, whereas the loser rapidly fled. During sexual interactions, the longer pedipalps of the male held legs IV of the female, whereas males with shorter pedipalps held the female by legs III. No contact with the male pedipalps and chelicerae by the females was visible before, during, or after copulation. Soon after copulating, males typically bent over the female, positioning their cheliceral horns against the females’s dorsum. Consequently, our data show that the cheliceral horns and the longer pedipalps of the male seem to play an important role, during both intersexual and intrasexual encountering.

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