scholarly journals Trophosome in vestimentifera Ridgeia piscesae Jones, 1985 (Annelida, Siboglinidae) develops from cells of the coelomic lining

2019 ◽  
Vol 485 (4) ◽  
pp. 519-522
Author(s):  
V. V. Malakhov ◽  
M. M. Gantsevich
Keyword(s):  
Cell Wall ◽  
The Body ◽  
Early Juvenile ◽  
Ridgeia Piscesae ◽  
Side Walls ◽  
Coelomic Lining ◽  
Chemoautotrophic Bacteria

The structure of early juvenile specimens of vestimentifera Ridgeia piscesae (Annelida, Siboglinidae) was studied. As adults, vestimentiphers are deprived of the intestine and have a trophosome, in which cells chemoautotrophic bacteria are living. In early juvenile individuals of 280-300 microns in size, it was found that trophosome develops from cells of the coelomic lining on the surface of the intestine and on the side walls of the body. This structure of the rudiment of the trofosome suggests that the bacteria are first captured by the cell wall of the body and then transferred to the cell on the surface of the intestine.

Designing a detachable body with sliding side walls and a roof

2021 ◽  
Vol 18 (1) ◽  
pp. 62-71
Author(s):  
O. I. Zaynitdinov ◽  
Keyword(s):  
Practical Importance ◽  
Atmospheric Precipitation ◽  
Middle Part ◽  
The Body ◽  
3D Design ◽  
Car Body ◽  
Simultaneous Loading ◽  
Side Walls ◽  
Loading And Unloading ◽  
Technical Solutions

Objective: Selection of technical solutions for designing a covered detachable body fence with sliding side walls and a roof. Methods: A detachable body with sliding side walls and a roof was designed in accordance with several technical and regulatory documents using the KOMPAS-3D design software. Results: The covered detachable body with sliding side walls and a roof designed for the carriage of goods that require protection from atmospheric precipitation has been proposed. A scheme of a lock for side sliding doors and a linkage scheme of the doors’ middle part have been developed. Drawings of the main load-bearing elements of the car body are presented, including the underframe with three longitudinal and several transverse and auxiliary beams. The diagram of fastening the sliding door roller assemblies on the car body to the lower longitudinal beams and to the upper beam is given. Practical importance: The covered detachable body with sliding side walls and a roof allows reducing the time and human effort of loading and unloading the car, provides simultaneous loading and unloading of goods both from the side and from the top of the body using various hoisting devices.

scholarly journals Gram Positive Bacterial Lipoteichoic Acid Role in a Root Canal Infection – A Literature Review

2021 ◽  
Author(s):  
Vinoo Subramaniam Ramachandran ◽  
Mensudar Rathakrishnan ◽  
Malathy Balaraman Ravindrran ◽  
Alargarsamy Venkatesh ◽  
Vidhya Shankari Shanmugasundaram ◽  
...  
Keyword(s):  
Cell Wall ◽  
Immune Surveillance ◽  
Lipoteichoic Acid ◽  
The Body ◽  
Gram Positive ◽  
Gram Negative ◽  
Cell Wall Components ◽  
Root Canals ◽  
Endodontic Infection ◽  
Wall Components

Bacteria and its by-products are found to be the main cause of pulpal and periapical infection of tooth. Infected root canals of tooth harbours a wide variation of microbial flora that includes both Gram-positive and Gram-negative microorganisms. Bacterial components such as Lipopolysaccharide (LPS) of gram negative bacteria and Lipoteichoic Acid (LTA) of gram positive bacteria have the potential to enter the peri-apical tissue of tooth and initiate the inflammatory process. After microbial death that occurs either due to body’s defence cells or by antibiotic action, bacterial cell wall components such as LTA are released which can persist inside macrophages for prolonged periods causing chronic inflammation. Once these cell-wall components are recognized by the body immune surveillance cells, numerous inflammatory mediators are released leading to inflammation and subsequent pathological consequences. The purpose of this review is intend to summarize the role of gram positive bacterial component LTA in causing endodontic infection and use of potential therapeutic agents against LTA.

scholarly journals Lipid Flippases for Bacterial Peptidoglycan Biosynthesis

2015 ◽  
Vol 8s1 ◽  
pp. LPI.S31783 ◽  
Author(s):  
Natividad Ruiz
Keyword(s):  
Cell Wall ◽  
The Body ◽  
Cellular Compartment ◽  
Peptidoglycan Biosynthesis ◽  
Lipid Ii ◽  
Common Strategy ◽  
Nucleotide Sugars ◽  
Membrane Bound ◽  
The Subject ◽  
Bacterial Peptidoglycan

The biosynthesis of cellular polysaccharides and glycoconjugates often involves lipid-linked intermediates that need to be translocated across membranes. Essential pathways such as N-glycosylation in eukaryotes and biogenesis of the peptidoglycan (PG) cell wall in bacteria share a common strategy where nucleotide-sugars are used to build a membrane-bound oligosaccharide precursor that is linked to a phosphorylated isoprenoid lipid. Once made, these lipid-linked intermediates must be translocated across a membrane so that they can serve as substrates in a different cellular compartment. How translocation occurs is poorly understood, although it clearly requires a transporter or flippase. Identification of these transporters is notoriously difficult, and, in particular, the identity of the flippase of lipid II, an intermediate required for PG biogenesis, has been the subject of much debate. Here, I will review the body of work that has recently fueled this controversy, centered on proposed flippase candidates FtsW, MurJ, and AmJ.

scholarly journals Nucleus-associated microtubules help determine the division plane of plant epidermal cells: avoidance of four-way junctions and the role of cell geometry.

1990 ◽  
Vol 110 (4) ◽  
pp. 1111-1122 ◽  
Author(s):  
D J Flanders ◽  
D J Rawlins ◽  
P J Shaw ◽  
C W Lloyd
Keyword(s):  
Cell Wall ◽  
Three Dimensional ◽  
Spatial Relationship ◽  
Epidermal Cells ◽  
Enzyme Treatment ◽  
Cross Wall ◽  
Nuclear Surface ◽  
Division Plane ◽  
Parallel Side ◽  
Side Walls

To investigate the spatial relationship between the nucleus and the cortical division site, epidermal cells were selected in which the separation between these two areas is large. Avoiding enzyme treatment and air drying, Datura stramonium cells were labeled with antitubulin antibodies and the three-dimensional aspect of the cytoskeletons was reconstructed using computer-aided optical sectioning. In vacuolated cells preparing for division, the nucleus migrates into the center of the cell, suspended by transvacuolar strands. These strands are now shown to contain continuous bundles of microtubules which bridge the nucleus to the cortex. These nucleus-radiating microtubules adopt different configurations in cells of different shape. In elongated cells with more or less parallel side walls, oblique strands radiating from the nucleus to the long side walls are presumably unstable, for they are progressively realigned into a transverse disc (the phragmosome) as broad, cortical, preprophase bands (PPBs) become tighter. The phragmosome and the PPB are both known predictors of the division plane and our observations indicate that they align simultaneously in elongated epidermal cells. These observations suggest another hypothesis: that the PPB may contain microtubules polymerized from the nuclear surface. In elongated cells, the majority of the radiating microtubules, therefore, come to anchor the nucleus in the transverse plane, consistent with the observed tendency of such cells to divide perpendicular to the long axis. In nonrectangular isodiametric epidermal cells, which approximate regular hexagons in section, the radial microtubular strands emanating from the nucleus tend to remain associated with the middle of each subtending cell wall. The strands are not reorganized into a single dominant transverse bar, but remain as a starlike array until mitosis. PPBs in these cells are not as tight; they may only be a sparse accumulation of microtubules, even forming along non-diametrical radii. This arrangement is consistent with the irregular division patterns observed in epidermal mosaics of isodiametric D. stramonium cells. The various conformations of the radial strands can be modeled by springs held in two-dimensional hexagonal frames, and by soap bubbles in three-dimensional hexagonal frames, suggesting that the division plane may, by analogy, be selected by minimal path criteria. Such behavior offers a cytoplasmic explanation of long-standing empirically derived "rules" which state that the new cell wall tends to meet the maternal wall at right angles. The radial premitotic strands and their analogues avoid taking the longer path to the vertex of an angle where a cross wall is already present between neighboring cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Fine structure of the growing point of the coenocytic alga, Caulerpa sertularioides

1969 ◽  
Vol 47 (10) ◽  
pp. 1599-1603 ◽  
Author(s):  
Arun K. Mishra
Keyword(s):  
Cell Wall ◽  
Fine Structure ◽  
Osmium Tetroxide ◽  
Axial Orientation ◽  
Parallel Orientation ◽  
Wall Formation ◽  
Cytoplasmic Vesicles ◽  
Side Walls

The coenocytic alga Caulerpa sertularioides (Gmelin) Howe was used for the study of the ultrastructure of cell wall and cytoplasm. After ultrasonic maceration and metal shadowing of the cell wall the microfibrils were observed to be random at the tip and parallel for each lamella of the subtip region and the mature portions of rhizome. The microfibrils in the two adjacent lamellae crossed each other at about right angles. The microfibrils of wall trabeculae were parallel to each other and to the long axis of the trabeculae. Fine structure studies of the algal cytoplasm were made using material fixed with glutaraldehyde and osmium tetroxide. The rhizome growing point was studied in detail. A gradient in the differentiation of cytoplasm was observed. The appearance varied from compact, homogeneous cytoplasm in the tip to a reticulate, vacuolate organization in the region farther back. Compartmentation in the cytoplasm was noted in the region immediately behind the compact, homogeneous cytoplasm of the tip region. Numerous smooth-walled vesicles were scattered throughout the growing point of the alga and were observed close to the plasmalemma near the cell wall. Microtubules with axial orientation were observed near the side walls of the alga. These also occurred in parallel orientation with respect to the microfibrils in the trabeculae at the growing points of the latter. The results were discussed with respect to the roles of microtubules and the cytoplasmic vesicles in the process of wall formation.

Baroclinic waves in a rotating fluid subject to internal heating

1970 ◽  
Vol 268 (1186) ◽  
pp. 201-232 ◽  
Keyword(s):  
Axisymmetric Flow ◽  
Side Wall ◽  
The Body ◽  
Radial Dependence ◽  
Outer Side ◽  
Rotating Fluid ◽  
Baroclinic Waves ◽  
Heating And Cooling ◽  
Side Walls ◽  
Periodic Fluctuations

Free thermal convection in a vertical rotating fluid annulus subject to axisymmetric heating and cooling applied at the side-walls has been the subject of extensive previous studies, one of the principal findings of which is that four distinct types of flow are possible, each characteristic of definite ranges of impressed experimental conditions. Three of these flow types are characterized by departures from axial symmetry and arise when the basic axisymmetric flow is ‘ baroclinically unstable ’; they comprise ‘ baroclinic waves ’ of varying degrees of complexity (steady waves, waves subject to periodic fluctuations in form, amplitude and/or wavenumber (‘vacillation’) and waves subject to irregular non-periodic fluctuations). The present paper reports an experimental and theoretical study of effects associated with the introduction of heat throughout the body of the fluid (rather than via one of the side-walls) and removal via the inner side-wall, the outer side-wall, or both side-walls simultaneously. The experiments show that the principal characteristics of the flow are fairly insensitive to the radial dependence of heating and cooling (upon which, for example, the horizontal shear of the basic axisymmetric flow depends), thereby strengthening the basis of the application to large-scale geophysical and astrophysical systems of theoretical ideas stemming from the laboratory work. Just as previous experiments have shown that the presence of an inner wall does not preclude the occurrence of irregular baroclinic waves, one of the present experiments shows that the absence of an inner wall does not preclude the occurrence of steady baroclinic waves (thus refuting a certain conjecture which seems to have gained widespread acceptance among meteorologists). Determinations have been made of the general form of the flow pattern, top-surface flow velocities, total heat transfer and the transition between axisymmetric flow and baroclinic waves, and the results interpreted, where possible, in terms of theoretical ideas. The experiments provide striking support for a simple theoretical model that treats the jet stream associated with the baroclinic waves as a quasigeostrophic detached thermal boundary layer.

scholarly journals THE HISTOLOGICAL DISTRIBUTION OF THE BLOOD GROUP SUBSTANCES IN MAN AS DISCLOSED BY IMMUNOFLUORESCENCE

1964 ◽  
Vol 119 (4) ◽  
pp. 503-516 ◽  
Author(s):  
Aron E. Szulman
Keyword(s):  
Cell Wall ◽  
Adult Life ◽  
First Trimester ◽  
Wide Distribution ◽  
The Body ◽  
Water Soluble ◽  
Epithelial Antigens ◽  
First Trimester Of Pregnancy ◽  
Blood Group Substances ◽  
Collecting Tubules

The ABH antigens have been mapped out in the tissues of embryos and fetuses, 18 to 125 mm crown to rump length, 6 to 14½ weeks ovulation age. Both the H and A,B antigens have the same distribution, and their spatial and temporal parallel obtains in intrauterine as well as extrauterine phases of life. The cell wall antigens are present in their maximal distribution in the youngest specimens available. They outline the endothelium of the cardiovascular system, and the cells of most of the epithelia throughout the body. The exceptions are the liver, the adrenal, and the nervous system, presumed to have lost the epithelial antigens at stages antedating the youngest specimens here described. The antigens of the stratified epithelia (and of the simple epithelia of the renal collecting tubules), together with the endothelial antigens, are permanent and persist into and throughout adult life. All other cell wall antigens disappear at a time characteristic for each organ. The antigenic recession coincides with recognizable steps of morphological advancement and often with assumption of function by the organ concerned; it is completed at about the end of the first trimester of pregnancy. The secretion-borne antigens first appear at the 35 to 40 mm stage (8 weeks ovulation age) in the salivary glands and in the stomach, to be followed in a constant sequence by the rest of the gastrointestinal tract, respiratory system, and pancreas. The secretion of these antigens persists throughout life. The early presence and wide distribution of the cell wall A,B antigens render them likely potential targets for maternal anti-A,B antibodies in heterologous pregnancies; the advent of the water-soluble substances at 8 weeks ovulation age may be providing a buffer shielding the fetal cell wall antigens by mopping up the maternal isoagglutinins.

scholarly journals Activation of Human and Chicken Toll-Like Receptors by Campylobacter spp.

2009 ◽  
Vol 78 (3) ◽  
pp. 1229-1238 ◽  
Author(s):  
Marcel R. de Zoete ◽  
A. Marijke Keestra ◽  
Paula Roszczenko ◽  
Jos P. M. van Putten
Keyword(s):  
Cell Wall ◽  
Inflammatory Response ◽  
Immune Responses ◽  
Host Response ◽  
The Body ◽  
Toll Like Receptors ◽  
Differential Host ◽  
Live Bacteria ◽  
Sense And Respond ◽  
Campylobacter Spp

ABSTRACT Campylobacter infection in humans is accompanied by severe inflammation of the intestinal mucosa, in contrast to colonization of chicken. The basis for the differential host response is unknown. Toll-like receptors (TLRs) sense and respond to microbes in the body and participate in the induction of an inflammatory response. Thus far, the interaction of Campylobacter with chicken TLRs has not been studied. Here, we investigated the potential of four Campylobacter strains to activate human TLR1/2/6, TLR4, TLR5, and TLR9 and chicken TLR2t2/16, TLR4, TLR5, and TLR21. Live bacteria showed no or very limited potential to activate TLR2, TLR4, and TLR5 of both the human and chicken species, with minor but significant differences between Campylobacter strains. In contrast, lysed bacteria induced strong NF-κB activation through human TLR1/2/6 and TLR4 and chicken TLR2t2/16 and TLR4 but not via TLR5 of either species. Interestingly, C. jejuni induced TLR4-mediated beta interferon in human but not chicken cells. Furthermore, isolated chromosomal Campylobacter DNA was unable to activate human TLR9 in our system, whereas chicken TLR21 was activated by DNA from all of the campylobacters tested. Our data are the first comparison of TLR-induced immune responses in humans and chickens. The results suggest that differences in bacterial cell wall integrity and in TLR responses to Campylobacter LOS and/or DNA may contribute to the distinct clinical manifestation between the species.

A Horseshoe Vortex in a Duct

1984 ◽  
Vol 106 (3) ◽  
pp. 668-676 ◽  
Author(s):  
J. Moore ◽  
T. J. Forlini
Keyword(s):  
Vortex Flow ◽  
Three Dimensional ◽  
Leading Edge ◽  
Horseshoe Vortex ◽  
The Body ◽  
Test Case ◽  
Three Dimensional Flow ◽  
Flow Measurements ◽  
Dimensional Flow ◽  
Side Walls

A Rankine half-body is used to model the three-dimensional flow caused by a blunt obstruction in a flow passage. The body is located in a duct bounded by two plane endwalls and two side walls shaped like potential-flow streamlines. A thick turbulent boundary layer on the endwall forms a horseshoe vortex flow as it encounters the leading edge of the body. Flow measurements are presented showing the inlet flow and the three-dimensional flow downstream of the leading edge. Sufficient data are presented for this to be a test case for the development of three-dimensional viscous flow codes.

scholarly journals Ram cult of funnel beaker culture tribes

2019 ◽  
Vol 23 ◽  
pp. 86-105
Author(s):  
Andrij Havinsky
Keyword(s):  
Key Words ◽  
Nearest Neighbors ◽  
The Body ◽  
Zigzag Line ◽  
Water Side ◽  
Line Characteristic ◽  
Cultural Layers ◽  
Side Walls ◽  
Funnel Beaker Culture ◽  
The Many

Among the variety of clay products of the Funnel beaker culture, there is almost no zoomorphic plastic. Such items include the handle of the vessels in the form of realistically shaped heads of the ram. And it is the only animal in the Funnel beaker culture, which is somehow expressed. Vessels with handles in a shape of rams and their fragments were found in a small amount. On the large territory, occupied by southeastern group of Funnel beaker culture and where hundreds of settlements are known, most of which were excavated only 60-70 figures were found in twenty sites. On some settlements many of such items were collected. For example, in Gródek (about 30), Zymno (18), Ćmielów (over 10) and on the others – only single finds. Also, on the many capitally examined sites such artifacts are absent. The rams decorated only the handles of jugs and pots. These vessels are usually ornamented. The ornament is constructed according to a clear scheme of world tree: rims are decorated with zigzag line, characteristic for ritual zoomorphic vessels of several agricultural cultures and interpreted as symbol of water. Side walls of the body are ornamented by a vertical ladder, which can be interpreted as grain ear. Paired handles in shape of rams, joined by sacred yoke which embodied sacral content of fertility. Most of the products, usually jars, were found in the storage pits, and some of the pots were found in women's graves. On the settlement of Zymno all figures were found in cultural layers and situated in separate concentrations. Such vessels were sacred – intended for the storage and sowing of grain, as well as for the ritual of praying for rain. Among ancient agricultural tribes, some animals, including ram, embodied the fertility cult and identified with certain forces of nature. The origins of the ram cult in the southeastern group of tribes of Funnel beaker culture are obviously can be found among its nearest neighbors, perhaps Trypillians, where such practices were more advanced. Key words: Funnel Beaker culture, ram cult, ritual, ornament, grain, water.

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