Structure of the labial palp of a larval elaterid (Coleoptera) and of sinus cells associated with its sensilla

1976 ◽  
Vol 54 (12) ◽  
pp. 2118-2128 ◽  
Author(s):  
F. W. Bellamy ◽  
R. Y. Zacharuk

Within each labial palp of the larval elaterid Ctenicera destructor (Brown) there is a terminal distal lymph sinus that is separated from the hemocoel in the prementum by a cellular mass in the distal two-thirds of the palp. The sensory neurons of the terminal sensilla form two ganglia that extend from the cellular mass into the prementum. Two types of cells intersperse and surround the cells associated with the sensilla. Elongate gobletlike cells, termed hemolymph sinus cells, extend from the hemocoel to the distal lymph sinus within the ganglia and through the cellular mass. Each contains a sinusoid that opens into the distal sinus. Cuboidal cells, termed basal hemolymph cells, are apposed to and interspersed between the bases of the sinus cells. Both types are associated with the basement membrane bounding the hemocoel and seem to transport materials from hemocoel to distal sinus and perhaps also secrete into the latter. Both types of cells may be differentiated hemocytes.

1977 ◽  
Vol 55 (3) ◽  
pp. 569-578 ◽  
Author(s):  
R. Y. Zacharuk ◽  
P. J. Albert ◽  
F. W. Bellamy

There are typically six elongate pegs positioned in longitudinal grooves in the outer walls of the distal segment of the labial palps of larvae of Ctenicera destructor (Brown). They are termed digitiform sensilla on the basis of their form and function. Each has a subapical pore typical of a contact chemoreceptor in surface scan, and a terminally branched dendrite but not the cuticular pores typical of a chemoreceptive porous hair. The dendritic terminations are encased by the dendritic sheath, the subapical pore is plugged in the wall of the peg, and there is only one innervating neuron, all of which are typical of a tactile mechanoreceptor. These pegs respond electrophysiologically to contact and vibratory stimuli, but not to the amino acids, sugars, salts, and water tested, nor to a changed pressure in the cephalic hemocoel.


Author(s):  
Bai-Wei Ma ◽  
Xin-Cheng Zhao ◽  
Bente G. Berg ◽  
Gui-Ying Xie ◽  
Qing-Bo Tang ◽  
...  

Author(s):  
D. E. Philpott ◽  
A. Takahashi

Two month, eight month and two year old rats were treated with 10 or 20 mg/kg of E. Coli endotoxin I. P. The eight month old rats proved most resistant to the endotoxin. During fixation the aorta, carotid artery, basil arartery of the brain, coronary vessels of the heart, inner surfaces of the heart chambers, heart and skeletal muscle, lung, liver, kidney, spleen, brain, retina, trachae, intestine, salivary gland, adrenal gland and gingiva were treated with ruthenium red or alcian blue to preserve the mucopolysaccharide (MPS) coating. Five, 8 and 24 hrs of endotoxin treatment produced increasingly marked capillary damage, disappearance of the MPS coating, edema, destruction of endothelial cells and damage to the basement membrane in the liver, kidney and lung.


Author(s):  
Jared Grantham ◽  
Larry Welling

In the course of urine formation in mammalian kidneys over 90% of the glomerular filtrate moves from the tubular lumen into the peritubular capillaries by both active and passive transport mechanisms. In all of the morphologically distinct segments of the renal tubule, e.g. proximal tubule, loop of Henle and distal nephron, the tubular absorbate passes through a basement membrane which rests against the basilar surface of the epithelial cells. The basement membrane is in a strategic location to affect the geometry of the tubules and to influence the movement of tubular absorbate into the renal interstitium. In the present studies we have determined directly some of the mechanical and permeability characteristics of tubular basement membranes.


Author(s):  
Douglas R. Keene ◽  
Gregory P. Lunstrum ◽  
Patricia Rousselle ◽  
Robert E. Burgeson

A mouse monoclonal antibody produced from collagenase digests of human amnion was used by LM and TEM to study the distribution and ultrastructural features of an antigen present in epithelial tissues and in cultured human keratinocytes, and by immunoaffinity chromatography to partially purify the antigen from keratinocyte cell culture media.By immunofluorescence microscopy, the antigen displays a tissue distribution similar to type VII collagen; positive staining of the epithelial basement membrane is seen in skin, oral mucosa, trachea, esophagus, cornea, amnion and lung. Images from rotary shadowed preparations isolated by affinity chromatography demonstrate a population of rod-like molecules 107 nm in length, having pronounced globular domains at each end. Polyacrylamide gel electrophoresis suggests that the size of this molecule is approximately 440kDa, and that it is composed of three nonidentical chains disulfide bonded together.


Author(s):  
John H. L. Watson ◽  
C. N. Sun

That the etiology of Whipple's disease could be bacterial was first suggested from electron micrographs in 1960. Evidence for binary fission of the bacteria, their phagocytosis by histiocytes in the lamina propria, their occurrence between and within the cells of the epithelium and on the brush border of the lumen were reported later. Scanning electron microscopy has been applied by us in an attempt to confirm the earlier observations by the new technique and to describe the bacterium further. Both transmission and scanning electron microscopy have been used concurrently to study the same biopsy specimens, and transmission observations have been used to confirm those made by scanning.The locations of the brush borders, the columnar epithelial cells, the basement membrane and the lamina propria beneath it were each easily identified by scanning electron microscopy. The lamina propria was completely filled with the wiener-shaped bacteria, Fig. 1.


Author(s):  
R.P. Nayyar ◽  
C.F. Lange ◽  
J. L. Borke

Streptococcal cell membrane (SCM) antiserum injected mice show a significant thickening of glomerular basement membrane (GBM) and an increase in mesangial matrix within 4 to 24 hours of antiserum administration (1,2,3). This study was undertaken to evaluate the incorporation of 3H proline into glomerular cells and GBM under normal and anti-SCM induced conditions. Mice were administered, intraperitoneally, 0.1 ml of normal or anti-SCM serum followed by a 10 µC/g body weight injection of 3H proline. Details of the preparation of anti-SCM (Group A type 12 streptococcal pyogenes) and other sera and injection protocol have been described elsewhere (2). After 15 minutes of isotope injection a chase of cold proline was given and animal sacrificed at 20 minutes, 1,2,4,8,24 and 48 hours. One of the removed kidneys was processed for immunofluorescence, light and electron microscopic radioautographic studies; second kidney was used for GBM isolation and aminoacid analysis.


Author(s):  
T. M. Murad ◽  
E. von Haam

Pericytes are vascular satellites present around capillary blood vessels and small venules. They have been observed in almost every tissue of the body and are thought to be related to vascular smooth muscle cells. Morphologically pericytes have great similarity to vascular endothelial cells and also slightly resemble myoepithelial cells.The present study describes the ultrastructural morphology of pericytes in normal breast tissue and in benign tumor of the breast. The study showed that pericytes are ovoid or elongated cells separated from the endothelial cell of the capillary blood vessel by the basement membrane of endothelial cell. The nuclei of pericytes are often very distinctive. Although some are round, oval, or elongated, others show marked irregularity and infolding of the nuclear membrane. The cytoplasm shows mono-or bipolar extension in which the cytoplasmic organelles are located (Fig. 1). These cytoplasmic extensions embrace the capillary blood vessel incompletely. The plasma membrane exhibits multiple areas of focal condensation called hemidesmosomes (Fig. 2, arrow). A variable number of pinocytotic vesicles are frequently seen lining the outer plasma membrane. Normally pericytes are surrounded by a basement membrane which is found more consistently on the outer plasma membrane separating the pericytes from the stromal connective tissue.


Author(s):  
Shirley Siew ◽  
Philip Troen ◽  
Howard R. Nankin

Testicular biopsies were obtained from six young male subjects (age range 24-33) who complained of infertility and who had clinical evidence of oligospermia. This was confirmed on histological examination which showed a broad spectrum from profound hypospermatogenesis to relatively normal appearing germinal epithelium. Thickening of the tubular walls was noted in half of the cases and slight peritubular fibrosis in one. The Leydig cells were reported as normal or unremarkable.Transmission electron microscopy showed that the thickening of the supporting tissue of the germinal epithelium was caused more by an increase in the thickness of the layers of the lamina propria than of the tubular wall itself. The changes in the basement membrane of the tubular wall consisted mostly of a greater degree of infolding into the tubule and some reduplication which gave rise to a multilayered appearance.


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