scholarly journals The development and function of the heart and pericardium in echinodermata

1932 ◽  
Vol 109 (764) ◽  
pp. 471-487 ◽  
Keyword(s):  
Connective Tissue ◽  
Blood Vessels ◽  
Circulatory System ◽  
Body Cavity ◽  
Point Of View ◽  
The Body ◽  
Ground Substance ◽  
Methyl Green ◽  
Ultimate Fate ◽  
And Function

The investigations which form the subject of the paper were begun with the object of verifying the statements made by several authors with regard to the origin and development of the so-called "heart" or pericardial vesicle of Echinoderms. A study of the literature soon led to the conclusion that our knowledge of the development of the organ was somewhat defective and that a thorough revision of its development and ultimate fate would be desirable. This work has occupied my attention for the last two years and the results obtained have been fairly satisfactory. Historical Resumé . The Echinodermata offer a number of most interesting problems to the comparative physiologist. They are in many senses the lowest animals, from the point of view of organisation, which possess a true cœlom or secondary body-cavity. It was always assumed by earlier naturalists that these animals must have a circulatory system and strenuous efforts were made to find a heart and blood-vessels. None of these efforts has been very successful because the so-called vessels were found to be mere rents in the loose connective tissue without proper walls of their own, and further, no connection could be traced between vessels in one part and those in another part. The fact that these vessels owe the honour of being denominated blood-vessels at all is because they contain a ground-substance, which unlike the ground-substance of the rest of the connective tissue, stains with aniline dyes such as eosin and methyl green. If there is to be true circulation some part of the system must be rhythmically contractile and so a heart had to be found. A pillar-like organ, lying alongiside the stone-canal in Echinoidea, Ophiuroidea and Asteroidea, was selected for the rôle. Unfortunately, in Holothuroidea, where the so called vessels are best developed, it is absent and this fact may be correlated with the elongated shape of the animal and the contractility of the body wall. Later, as repeated observation had failed to detect any sign of its beating, the non-committal term of "pseudo-heart" was adopted for it. It is now proposed to call it the “pericardial vesicle.”

scholarly journals II. Note on the intracellular development of blood-corpuscles in mammalia

1874 ◽  
Vol 22 (148-155) ◽  
pp. 243-245 ◽  
Keyword(s):  
Connective Tissue ◽  
Blood Vessels ◽  
The Body ◽  
Ground Substance ◽  
Fat Cells ◽  
New Born ◽  
Subcutaneous Connective Tissue ◽  
The Difference ◽  
Vacuolated Cells ◽  
In Cells

If the subcutaneous connective tissue of the new-born rat is examined under the microscope in an indifferent fluid, it is found to consist chiefly of an almost homogeneous hyaline ground-substance, which is traversed by a few wavy fibres, and has a considerable number of exceedingly delicate, more or less flattened cells scattered throughout the tissue. The cells here spoken of are of course the connective-tissue corpuscles. They are not much branched as a rule (at any rate their branches do not extend far from the body of the corpuscle), and they are mainly distinguished by the extraordinary amount of vacuolation which they exhibit—by which is meant the formation within the protoplasm of minute clear spherules, less refractive than that substance, and probably, therefore, spaces in it containing a watery fluid. The nuclei, of which there is generally not more than one in each cell, are frequently obscured by the vacuoles, but, when visible, are seen to be round or oval in shape and beautifully clear and homogeneous; they commonly contain either one or two nucleoli. It is from these cells that the blood-vessels of the tissue are formed, and within them, red, and perhaps also, white blood-corpuscles become developed. Of the vacuolated cells above described some possess a distinct reddish tinge, either pretty evenly diffused over the whole corpuscle, or in one or more patches, not distinctly circumscribed, but fading off into the surrounding protoplasm. Others contain either one, two, or a greater number of reddish globules, consisting apparently of hæmoglobin. These vary in size, from minute specks to spherules as large as, or even larger than, the red corpuscles of the adult: in cells which are apparently least developed it is common to find them of various sizes in the same cell; whereas cells which are further advanced in development are not uncommonly crowded with hæmoglobin-globules, tolerably equal in point of size, and differing from the adult corpuscle only in shape. It is important to remark that there is, at no time, an indication of any structure within the globules resembling a nucleus: the nucleus of the cell also appears, up to this point at least, to undergo no change. In fact the formation of the hæmoglobin-globules reminds one rather of a deposit within the cell-substance such as occurs in developing fat-cells, the difference being that in the latter case the deposited globules eventually run together into one drop, whereas in the former they remain distinct as they increase in size and eventually take on the flattened form.

scholarly journals Morphofunctional and immunohistochemical characteristics of the large omentum in ovarian cancer

2020 ◽  
Vol 9 (3) ◽  
pp. 64-71
Author(s):  
N. N. Shevlyuk ◽  
L. V. Khalikova ◽  
A. A. Khalikov
Keyword(s):  
Ovarian Cancer ◽  
Connective Tissue ◽  
Protein Expression ◽  
Blood Vessels ◽  
Lymphoid Tissue ◽  
P53 Protein ◽  
Individual Variability ◽  
The Body ◽  
Great Omentum ◽  
Low Grade

The aim of the study was to establish morphofunctional and immunohistochemical characteristics of large omentum in women with ovarian cancer.Material and methods. The large omenta of 48 women with ovarian cancer (low-grade differentiated seropapillary adenocarcinoma of high-grade malignancy) of II stage (n=20) and III stage (n=28) were studied. Histological sections were stained with overview histological and immunohistochemical methods (to reveal ki67, P53, CD34, CD7, CD4, CD8, CD61 proteins expression). Results. In patients, the size of the large omentum was characterized by high individual variability; in the presence of metastasis, the size of the omentum was reduced. Intensive development of blood vessels in the organ was noted, but in the presence of metastases stasis of blood corpuscles, leucocytic infiltration, and moderate edema of connective tissue were observed in the organ’s vessels. Areas of lymphoid tissue, both small lymphatic follicles and diffusely located lymphoid tissue, were revealed in the omentum. In most follicles, reactive centers were not marked, and the number of follicles was reduced in the presence of metastases in the omentum. The analysis of CD34+ cells distribution showed that they were identified both in the tumor and in the areas of the omentum adjacent to the tumor, which indicates a pronounced angiogenesis. An irregular distribution of CD7+ and CD8+ and CD4+ cells was revealed in the tumor tissues, as well as in the surroundings. Simultaneously with the expression of P53 protein, ki67 protein expression is revealed in the significant number of tumor cells (including endothelial cells of tumor blood vessels). The proportion of ki67+ cells in the tumor cell population was 60.1±3.3%. The presence of a large number of ki67+cells in the presence of P53 protein expression in them indicates the aggressiveness of the tumor, as well as a disturbance of apoptosis regulatory mechanisms in the cells. Ki67 expression was low in the omentum areas unaffected by metastases, and it was revealed in the certain areas of connective tissue in fibroblastic programmed differentiation cells. Conclusion. The results obtained indicate significant plasticity and reactivity of great omentum in the presence of tumor process in the body and confirm the important role of great omentum in protective reactions.

scholarly journals A HISTOLOGICAL STUDY OF THE SKIN LESIONS OF PELLAGRA

1911 ◽  
Vol 13 (1) ◽  
pp. 98-114
Author(s):  
Fraser B. Gurd
Keyword(s):  
Epithelial Cells ◽  
Connective Tissue ◽  
Blood Vessels ◽  
Pathological Condition ◽  
Histological Study ◽  
The Body ◽  
Lymphoid Cells ◽  
Cutaneous Lesions ◽  
Predisposing Factor ◽  
Pigment Formation

The cutaneous lesions in pellagra consist of an early erythema, or, in occasional cases, of vesicles or bullous formations which are followed by hyperkeratosis and pigmentation, resulting in a dry, dark brown scaliness. These various lesions are similar to those normally produced by the action of sunlight, but are much more marked. The histological phenomena of the erythematous and bullous stage are those of a mild acute inflammatory reaction, together with a degeneration in the superficial layers of the corium. Following this degeneration, which involves not only the general connective tissue but the connective tissue of the blood vessels, there is a reparative change evidenced histologically by an increased cellularity of the corium and the presence of fibroblasts. The capillaries also are increased in number and much dilated. Apparently as a result of this increased vascularity of the corium, there is an increased proliferation of the epithelium resulting in a thickening of the epidermis. This increase in thickness of the epithelial layer is especially marked in the prickle cells and the stratum granulosum. In the later stages, in an effort to secure a firm basement membrane, the epithelium is seen to dip down deeply into the rarefied connective tissue. About the blood vessels during the reactionary process are found collections of lymphoid cells, a few plasma cells, but no mast cells or eosinophiles. That the irritant producing the degeneration in the corium is sunlight in the presence of some predisposing factor, is suggested by the enormous increase in pigment formation in the epithelial cells and by the large number of chromatophores in the superficial layers of the corium. This pigmentation is autochthonous in both types of cell. There is no reason for believing that the pigment is formed in the cells of the corium and thence discharged into the epithelium, or that the reverse process takes place. The predisposing factor inducing the changes in the corium is, apparently, a lessened resistance of the epithelium to the violet and ultra-violet rays, due to some metabolic insufficiency on the part of the epithelial cells. Further observation may justify the conclusion that throughout the body, pellagra is a disease essentially of the epithelium, including the nervous system, this pathological condition manifesting itself by an insufficient or altered function.

Development of the larval tunic in a compound ascidian: morphogenetic events in the embryos of Distaplia occidentalis

1984 ◽  
Vol 62 (12) ◽  
pp. 2392-2400 ◽  
Author(s):  
Michael J. Cavey ◽  
Richard A. Cloney
Keyword(s):  
External Surface ◽  
Body Cavity ◽  
The Body ◽  
Ground Substance ◽  
Perivitelline Space ◽  
Outer Compartment ◽  
Test Cells ◽  
Principal Elements

The larval tunic of Distaplia occidentalis is a complex investment consisting of extracellular filaments and an amorphous ground substance. The principal elements of the tunic are two thin cuticles and two subcuticular compartments. Compacted filaments and small amounts of ground substance characterize the cuticles. Dispersed filaments and large amounts of ground substance distinguish the compartments. The cells of the embryonic epidermis apparently secrete both the filaments and the ground substance. The elements of the larval tunic differentiate sequentially over a period of approximately 2 weeks. The outer cuticle appears 3–4 days after neurulation and it gradually lifts from the surface of the epidermis as the outer compartment forms. Tapered folds of the outer cuticle and extensions of the outer compartment produce the dorsal, ventral, and posterior fins of the larva. Test cells, occupying the perivitelline space around the embryo, release multigranular "ornaments" that adhere to the external surface of the outer cuticle. The inner cuticle and the inner compartment arise during the 4 days prior to hatching. The inner compartment over the truncal epidermis expands significantly to accommodate cells which emigrate from the body cavity (hemocoel).

scholarly journals The intracranial vascular system of sphenodon

1909 ◽  
Vol 81 (548) ◽  
pp. 290-291 ◽  
Keyword(s):  
Blood Vessels ◽  
Vascular System ◽  
Foramen Magnum ◽  
Body Cavity ◽  
The Body ◽  
Cephalic Vein ◽  
Special Method ◽  
Cranial Cavity ◽  
The Right ◽  
The Brain

This memoir contains a detailed description, with illustrations, of the intracranial blood-vessels of the Tuatara, of which no account has hitherto been published. The description is belived to be more complete than any hithero given for any reptile, and a considerable number of vessels are described which have not hithero been noted in Lacertilia. This comparative completeness of detail is largely due to the employment of a special method of investigation. By this method the entire contents of the cranial cavity are fixed and hardened in situ , and are then in excellent condition either for dissection or for histological purposes. The brain does not occupy nearly the whole of the cranial cavity, there being a very large subdural space (especially above the brain), across which many of the blood-vessels run, together with delicate strands of connective tissue which connect the dura mater with pia. The eyeballs are removed and an incision is made on each side in the cartilaginous wall which separates the cranial cavity from the orbit. Acetic bichromate of potash (made up according to the formula given by Bolles Lee) is injected in to the cranial cavity through these incision, and the entire animal, after opening the body cavity, is suspended in a large volume of the same fluid for about five days, and then graded up to 70 per cent. Alcohol. When the cranial cavity is now opened up the cerebral vessels are seen with extraordinary distinctness, although they have not been artifically injected. Futher details were made out by means of serial sections, both transverse and longitudinal, and both of the adult and of advanced embroyes (Stage S). In most respect the arrangement of the intracranical blood-vessels agrees with found in the Lacertilia, so far as these have been investigated, but there is an important difference in the fact that the posterior cephalic vein leaves the cranial cavity through the foramen jugulare and not through the foramen magnum, while a slightly more primitive condition is shown in the less complete union of the right and left halves of the basilar artery. Sphenodon makes some approach to the condition of the Chelonia in this latter respect, but differs conspicuously from this group in the fact that the circle of Willis is not completed anteriorly, as well as in the fact that no branch of the posterior cephalic vein leaves the cranial cavity through the foreman magnum. A very characteristic features of Sphenodon is the development of large transverse sinues resembling those of the crocodile, but these communicate with the extracranial vascular system in quite a different manner from that described by Rathke in the latter animal.

The internal anatomy of Typhlops schneider (Reptilia)

1960 ◽  
Vol 8 (2) ◽  
pp. 181 ◽  
Author(s):  
J Robb
Keyword(s):  
Connective Tissue ◽  
Reproductive Organs ◽  
Body Cavity ◽  
The Body ◽  
The Other ◽  
Internal Anatomy ◽  
Reproductive Systems ◽  
Male And Female ◽  
Connective Tissue Sheath ◽  
First Time

The internal anatomy of Typhlops shows a number of interesting features which support the hypothesis that the typhlopids are wrongly classified among the Ophidia, and that they should either be given subordinal rank, equivalent to the Sauria and the Serpentes, or be made an infra-order of the Sauria. The alimentary, vascular, respiratory, and reproductive systems are described in detail for the first time. The most striking peculiarities occur in the respiratory and reproductive systems. Unlike most snakes, Typhlops has two functional lungs, one occupying most of the anterior third of the body cavity, and the other smaller one lying immediately behind it. All the pulmonary blood vessels are well developed. The male reproductive organs are solid, grooved, protrusible structures, each of which is contained within a connective tissue sheath in the postanal region. These organs are unlike the hemipenes of any snake or lizard of which a description can be found. Both male and female animals possess a large cloaca1 gland in the postanal region. There are also several uncommon features in the alimentary and vascular systems.

scholarly journals Importance of intramuscular connective tissue for meat quality

2016 ◽  
Vol 72 (10) ◽  
pp. 600-603
Author(s):  
Magdalena Górska ◽  
Dorota Wojtysiak
Keyword(s):  
Connective Tissue ◽  
Meat Quality ◽  
Quality Parameters ◽  
The Body ◽  
Collagen Content ◽  
Meat Tenderness ◽  
Physico Chemical ◽  
Extracellular Matrix Components ◽  
Important Quality ◽  
And Function

During ageing, meat undergoes many structural and biochemical changes which make it possible to obtain meat of specific taste and physico-chemical parameters. One of the most important quality parameters is meat tenderness and juiciness. This work presents the results of studies concerning the possible effect of intramuscular connective tissue (IMCT) on the final meat quality. The amount, quality and organization of this tissue depend on the type of muscle, as well as its location in the carcass and function in the body. Muscles with high amounts of IMCT are generally less tender due to a considerable collagen content. The breakdown of IMCT network increases collagen solubility and decreases the number of extracellular matrix components, which may lead to increased meat tenderness and reduced meat juiciness. However, the final meat quality is determined not only by the proportion of connective tissue in the muscle structure, the size and organization of collagen fibres, the intramuscular fat content and the total collagen level, but also by the soluble collagen content. The effect of IMCT on the final meat quality requires further research, mainly at the molecular level.

The Structure and Development of the Segmental Excretory Organs of Asellus aquaticus (Linné)

1942 ◽  
Vol s2-83 (330) ◽  
pp. 205-243
Author(s):  
A. E. NEEDHAM
Keyword(s):  
Connective Tissue ◽  
Compact Group ◽  
Duct Cell ◽  
Large Cell ◽  
Body Cavity ◽  
The Body ◽  
Small Cells ◽  
Morphological Evidence ◽  
Exit Tube ◽  
Excretory Organs

1. The maxillary organ (‘gland’) of Asellus is pyramidal in form and consists of an end sac in the form of an inverted V placed transversely to the body, a duct describing four vertical loops, one anterior and three posterior to the end sac, and a chitin-lined exit-tube leading from the duct to the exterior and enlarging along its course into a bladder. A sphincter consisting of four cells with two sets of intracellular fibrils controls the aperture from end sac into duct. The external aperture is on the medio-posterior face of the limb-base. The organ is anchored to various points on the exoskeleton by connective tissue strands. The spaces among the coils are partly filled by cells which accumulate reserve materials but leave channels for the circulation of blood. Histologically the organ resembles those of other Crustacea in all essentials. 2. The exit-tube is ectodermal, the rest of the organ mesodermal. Duct and end sac originate from independent rudiments, the former from a single large cell (? nephroblast) located where the medial wall of the maxilla joins the body, the end sac from a number of smaller, scattered cells dorso-laterally to the duct rudiment. Duct and end sac are probably derived from the second and third mesodermal teloblasts respectively. The sphincter originates from the end sac. Cells of the genital rudiment are associated with the end sac in early stages. 3. There is considerable evidence that the segmental excretory organs are homologous throughout the Crustacea. 4. They differ from the coelomoducts of other Arthropods and of other phyla in having a composite structure. 5. This suggests that the duct may be homologous with the nephridia of other groups of animals. There is functional and morphological evidence for this but nephridia are typically ectodermal in origin, so that if they are homologous there must have been a movement of the presumptive nephridioderm, during the evolution of the Crustacea, from the ectoderm to the mesoderm. 6. The antennal organ ofAsellus (Némée's gland) consists of a compact group of five large cells containing intracellular vacuoles. It is suspended in the body cavity by connective tissue strands, and has no external opening. A nerve supplies it from the antennal ganglion. In the adult it appears to be an organ of internal secretion: the vacuoles have been seen in the distended and in the exhausted phases. 7. Néméc's gland originates close to the epidermis at the antennal-mandibular intersegment. It appears to be mesodermal and probably represents the duct of the typical segmental organ (not the end sac). 8. Ter-Poghossian's organ, consisting of a large number of small cells in a compact group attached to the ventral epidermis, median and anterior to Nemec's gland, has no other anatomical relations. It appears to be ectodermal in origin. 9. The ‘rosette’ glands resemble structurally the tegumental glands of Decapods. The gland cells appear to be mesodermal, but the origin of the central duct cell was not determined. 10. Gastrulation in Asellus is essentially similar to the process in other Malacostraca, but it seems possible that the distinction between naupliar and post-naupliar regions is not so sharp as has usually been maintained. 11. The value of the embryological evidence concerning the homology of the parts of the second maxilla is considered. It does not entirely agree with interpretations based on adult morphology.

On a New Species of the Genus Saurositus from an Indian lizard

1965 ◽  
Vol 39 (2-3) ◽  
pp. 137-140
Author(s):  
P. G. Deshmukh ◽  
S. Mehdi Ali
Keyword(s):  
New Species ◽  
Connective Tissue ◽  
Body Cavity ◽  
The Body ◽  
Body Diameter ◽  
Calotes Versicolor ◽  
Maximum Body ◽  
A New Species

Three specimens of this species were collected on one occasion from the lizard Calotes versicolor. The material consists of one male and two females which were found entangled in the connective tissue of the body cavity.These are thin worms measuring 11·5 mm. long in the male and 18·3 mm. in the female. The maximum body diameter is 0·23 and 0·35 mm. respectively in the male and the female.

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