The Peri-Renal Tissue of Protopterus A Contribution to the History of the Adrenal

1956 ◽  
Vol s3-97 (37) ◽  
pp. 123-154
Author(s):  
W. HOLMES ◽  
D. E. MOORHOUSE

The animal studied was the lungfish Protopterus aethiopicus; the investigation was histological and cytochemical, the material being freshly taken from East African lakes. The peri-renal tissue is a substantial organ which, because it surrounds the kidney, extends through the greater part of the body cavity. Those who have investigated its structure in recent years have considered it to be a haematopoietic organ. A wide variety of histological, histochemical, and haematological techniques was used. The organ is shown to contain five characteristic kinds of tissue; these are named: lipid, endothelial, pigmented, round-cell, and steroid tissue respectively. The lipid tissue is characterized by cytoplasmic liposomes--droplets containing phospholipid. In one type of cell, the ‘small lipid cell’, which may be related to the eosinophil granulocytes of the blood, the droplets have a relatively small diameter. In a second type, the ‘large lipid cell’, the droplets grow to a much larger diameter, and show evidence of cycles of activity involving increase and disappearance of the phospholipid. Histochemical interpretations are made difficult by the finding that this phospholipid does not colour with Sudan black. The endothelial tissue is composed of phagocytic (macrophage) cells some of which are elongated and line vascular sinusoids while others are spherical and contain larger inclusions. These inclusions have some lipid characteristics and may be a manifestation of the translocation of lipid within the organ. The pigmented tissue is composed of melanophores and of a second, round, type of cell which shows evidence of relationship with the macrophage system. Both kinds of cell contain ‘melanin’; the second also has inclusions with different histochemical properties. The round-cell tissue, found in nodules, has a general resemblance to lymphoid tissue. It is doubtful whether its cells are lymphocytes, but it has not been found possible to characterize them in any other way. The steroid tissue is composed of cells which react positively to the histochemical tests comprised in the ‘steroid repertoire’, as used in the study of the mammalian adrenal. Attention is drawn to technical difficulties which may have confused the study of the peri-renal tissue as a haematopoietic organ. The connexion between the lipid tissue and circulating granulocytes has features which distinguish it from the processes of granulocyte formation in the spleen. There are strong indications of an evolutionary connexion between peri-renal tissue and the cortex of the adrenal gland of higher animals. The lungfish may offer the best starting-point for the study of the comparative histology of the adrenal of tetrapods. The association between lipid, steroid, haematopoietic, macrophage, and pigment tissue has parallels in function in the complex interrelations of the mammalian adrenal.

2018 ◽  
Vol 285 (1881) ◽  
pp. 20180296 ◽  
Author(s):  
Pei-Yun Cong ◽  
Thomas H. P. Harvey ◽  
Mark Williams ◽  
David J. Siveter ◽  
Derek J. Siveter ◽  
...  

Chancelloriids are an extinct group of spiny Cambrian animals of uncertain phylogenetic position. Despite their sponge-like body plan, their spines are unlike modern sponge spicules, but share several features with the sclerites of certain Cambrian bilaterians, notably halkieriids. However, a proposed homology of these ‘coelosclerites' implies complex transitions in body plan evolution. A new species of chancelloriid, Allonnia nuda , from the lower Cambrian (Stage 3) Chengjiang Lagerstätte is distinguished by its large size and sparse spination, with modified apical sclerites surrounding an opening into the body cavity. The sclerite arrangement in A. nuda and certain other chancelloriids indicates that growth involved sclerite addition in a subapical region, thus maintaining distinct zones of body sclerites and apical sclerites. This pattern is not seen in halkieriids, but occurs in some modern calcarean sponges. With scleritome assembly consistent with a sponge affinity, and in the absence of cnidarian- or bilaterian-grade features, it is possible to interpret chancelloriids as sponges with an unusually robust outer epithelium, strict developmental control of body axis formation, distinctive spicule-like structures and, by implication, minute ostia too small to be resolved in fossils. In this light, chancelloriids may contribute to the emerging picture of high disparity among early sponges.


2019 ◽  
Vol 37 (2) ◽  
pp. 206-219
Author(s):  
Meindert E. Peters

Friedrich Nietzsche's influence on Isadora Duncan's work, in particular his idea of the Dionysian, has been widely discussed, especially in regard to her later work. What has been left underdeveloped in critical examinations of her work, however, is his influence on her earlier choreographic work, which she defended in a famous speech held in 1903 called The Dance of the Future. While commentators often describe this speech as ‘Nietzschean’, Duncan's autobiography suggests that she only studied Nietzsche's work after this speech. I take this incongruity as a starting point to explore the connections between her speech and Nietzsche's work, in particular his Thus Spoke Zarathustra. I argue that in subject and language Duncan's speech resembles Nietzsche's in important ways. This article will draw attention to the ways in which Duncan takes her cues from Nietzsche in bringing together seemingly conflicting ideas of religion and an overturning of morality; Nietzsche's notion of eternal recurrence and the teleology present in his idea of the Übermensch; and a renegotiation of the body's relation to the mind. In doing so, this article contributes not only to scholarship on Duncan's early work but also to discussions of Nietzsche's reception in the early twentieth century. Moreover, the importance Duncan ascribes to the body in dance and expression also asks for a new understanding of Nietzsche's own way of expressing his philosophy.


Parasitology ◽  
1924 ◽  
Vol 16 (1) ◽  
pp. 111-112
Author(s):  
Edward Hindle

In December, 1922, whilst dissecting a large female example of Bufo regularis, one of my students noticed a cylindrical structure extending along the ventral region of the body-cavity. A careful examination showed that this structure consisted of an elongated sac-like diverticulum of the right lung, containing an almost full-grown specimen of a dipterous larva, which could be seen through the membraneous wall of the diverticulum. The base of the latter, in addition to its point of origin from the lung, was also connected to the dorsal surface of the liver by strands of fibrous tissue, suggesting that the growth had been in existence some considerable time in order to cause such adhesions. Posteriorly, the diverticulum hung freely in the body cavity and extended to the extreme hinder end. Its dimensions were 5·5 cm. in length, by 0·5 cm. in diameter, but tapering towards each extremity.


1962 ◽  
Vol 40 (7) ◽  
pp. 1269-1275 ◽  
Author(s):  
Joan F. Bronskill

In third and fourth instar larvae of Aedes aegypti (L.), juveniles of the rhabditoid, DD136, penetrate the blood sinus and cardial epithelium of the proventriculus to enter the body cavity of the host, where they complete their development. By 5 hours, a thick capsule developed about many of the ensheathed immature adults of DD136 within the body cavity of A. aegypti larvae. This rapid defence reaction of the mosquito to DD136, which has both a melanin and a cellular manifestation, occurs both in the exotic mosquito A. aegypti and in the two endemic species tested, Aedes stimulans (Walker) and Aedes trichurus (Dyar). The resistance of A. stimulans to an endemic rhabditoid, possibly of the Diplogasteridae, is also similar. The histological structure of the capsule is not affected during metamorphosis in A. aegypti; however, during histogenesis of adult tissue displacement and (or) distortion of some tissues and organs may be caused by the presence of the capsule within the host's body cavity. The activity of the adult A. aegypti is normal when this distortion or displacement is minor. Though usually encapsulated DD136 are retained within the body cavity of A. aegypti during metamorphosis, sometimes they are partially or completely expelled from the host's body cavity at the time of molting.


1971 ◽  
Vol 55 (1) ◽  
pp. 13-38 ◽  
Author(s):  
C. J. PENNYCUICK

1. Glide-comparison measurements were made on ten species of East African soaring birds using a Schleicher ASK-14 powered sailplane. Horizontal and vertical speed differences between bird and glider were measured by a photographic method, and used to estimate the bird's horizontal and vertical speeds relative to the air. The analysis refers to the white-backed vulture, since by far the largest number of measurements was obtained on this species. 2. A regression analysis using a two-term approximation to the glide polar yielded an implausibly high estimate of induced drag, which was attributed to a lack of observations at lift coefficients above 0.72. An amended glide polar was constructed assuming elliptical lift distribution and a maximum lift coefficient of 1.6 to define the low-speed end, while the high-speed end was made to pass through the mean horizontal and sinking speeds of all the experimental points. This curve gave a minimum sinking speed of 0.76 m/s at a forward speed of 10 m/s, and a best glide ratio of 15.3:1 at 13 m/s. It did not differ significantly (in the statistical sense) from the original regression curve. 3. In comparing the estimated circling performance, based on the amended glide polar, with that of the ASK-14, it was concluded that the rates of sink of both should be comparable, but that the glider would require thermals with radii about 4.3 times as great as those needed to sustain the birds. The conclusions are consistent with experience of soaring in company with birds. 4. In an attempt to assess the adaptive significance of the low-aspect-ratio wings of birds specializing in thermal soaring, the white-backed vulture's circling performance was compared with that of an ‘albatross-shaped vulture’, an imaginary creature having the same mass as a white-backed vulture, combined with the body proportions of a wandering albatross. It appears that the real white-back would be at an advantage when trying to remain airborne in thermals with radii between 14 and 17 m, but that the albatross-shaped vulture would climb faster in all wider thermals; on account of its much better maximum glide ratio, it should also achieve higher cross-country speeds. It is concluded that the wing shape seen in vultures and storks is not an adaptation to thermal soaring as such, but is more probably a compromise dictated by take-off and landing requirements. 5. The doubts recently expressed by Tucker & Parrott (1970) about the results and conclusions of Raspet (1950a, b; 1960) are re-inforced by the present experience.


1956 ◽  
Vol s3-97 (40) ◽  
pp. 519-534
Author(s):  
D. E. MOORHOUSE

The experiments were carried out on Protopterus aethiopicus in East Africa. They were: the injection of commercial adrenocorticotrophic hormone, hypophysectomy, administration of ACTH after hypophysectomy, artificially induced aestivation, and artificially induced ‘stress’. The two elements of the lipid tissue show differing reactions to the experiments carried out. The large lipid cells appear to be under direct pituitary control: active secretion follows ACTH administration, hypophysectomy leads to a blocking of secretion. After ‘stress’ and hypophysectomy the small lipid cells develop sudanophil inclusions which are positive to the histochemical tests for steroids. This does not occur after ACTH administration. The phagocytes of the endothelial system take part in the transfer of material within the peri-renal tissue; this is shown by their cytology after ACTH administration and ‘stress’. Evidence from these experiments indicates that the round pigment cells characteristic of the normal animal are syncytial structures formed by the fusion of phagocytic cells containing pigment and remains of large lipid cells. The steroid tissue shows little change in these experiments other than a decrease in the amount of steroid material after ACTH, and a more intense staining of the mitochondria after hypophysectomy. The number of eosinophil leucocytes increases as the result of ACTH administration. The round cell nodules showed no detectable changes in these experiments.


1949 ◽  
Vol 26 (1) ◽  
pp. 1-15
Author(s):  
J. D. SMYTH

1. Plerocercoid larvae of the pseudophyllidean cestode Ligula intestinalis from the body cavity of roach, were cultured in vitro at 40°C. in a variety of saline and nutrient media. About 65% of such cultures were aseptic. 2. During cultivation, larvae produced acid by-products (unidentified) and the pH fell rapidly. 3. The presence of these acid by-products slowed down development, or, if present in sufficient quantity, caused death. 4. In order to obtain development in nutrient media in a period (3 days) comparable to that required in a bird (the normal host) it was necessary to renew the medium 24-hourly. 5. 6% of the eggs produced from a worm cultured in horse serum were fertile. Fertile eggs were never obtained from larvae cultured in any other media. 6. Certain bacterial infections had no apparent detrimental effect on development, but others were toxic. 7. Some larvae underwent development in non-nutrient medium (¾ strength Locke's solution). The exact conditions under which this occurred was not determined. 8. Fragments (3 cm. long), of larvae or larvae with either scolex or posterior half removed, underwent development to the stage of oviposition in nutrient media. 9. Histochemical examination revealed that the plerocercoid larvae were almost fat-free. During cultivation, very large quantities of cytoplasmic fat were produced the quantity being proportional to the duration of cultivation. Fat was produced even under starvation conditions (i.e. during cultivation in saline) and can be considered a metabolic by-product. 10. The fresh plerocercoid contained great quantities of glycogen in the parenchyma and muscle regions. After cultivation in nutrient or saline media, considerable quantities were still present.


Author(s):  
M. Barson

Clarias gariepinus were collected from Lake Chivero, Zimbabwe, and examined for nematode parasites from November 2000 to May 2002. Of the 202 specimens collected, 42.6 % were infected with third-stage larvae of Contracaecum sp. in the body cavity. The intensity of the infection was 1-7 worms per fish (mean intensity = 2.2). Seasonal variation in the prevalence of the parasite was not obvious and there was no significant difference in the prevalence of infection between males and females (c2 = 2.228; P > 0.05). No significant relationship between host size and prevalence was established. There was also no significant relationship between intensity and the body condition factor (r = 0.11; P > 0.05). The low parasite prevalence may have been caused by the disruption of the infection cycle since piscivorous birds, which are the final hosts of the parasite, do not feed on C. gariepinus in Lake Chivero.


1998 ◽  
Vol 72 (4) ◽  
pp. 3377-3382 ◽  
Author(s):  
John W. Barrett ◽  
Andy J. Brownwright ◽  
Mark J. Primavera ◽  
Subba Reddy Palli

ABSTRACT A recombinant Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) expressing the green fluorescence protein (GFP) under the control of the AcMNPV polyhedrin promoter was constructed to study the spatial and temporal regulation of baculovirus infection in a permissive host. Larvae that ingested AcMNPV-GFP showed localized expression of GFP in the midgut epithelial cells, as well as hemocytes, at 24 h postinfection. The presence of fluorescence in these tissues indicated not only that the virus was replicating but also that the very late viral proteins were being synthesized. Secondary infection occurred within the tracheal cells throughout the body cavity, confirming earlier reports, and these foci of infection allowed entry of the virus into other tissues, such as the epidermis and the fat body.


1970 ◽  
Vol 60 (1) ◽  
pp. 33-42 ◽  
Author(s):  
D. J. Greathead

The relations of the Strepsipterous parasite Halictophagus pontifex Fox to seven species of its Cercopid (Aphrophorinae) hosts were studied at a grassland site in Uganda. Dissections of weekly samples of the Cercopids collected by sweeping showed that the duration of the life-cycle of H. pontifex is 30–40 days. The parasite is found only in adult hosts which can support as many individuals (up to 7) in Poophilus costalis (Wlk.) as can develop in the space available in the body cavity. Both the maximum number of parasites per host and the rate of parasitism are related to the volume of the host. Parasitism arrests development of the ovaries of female hosts; they may reproduce after emergence of male parasites but not after exhaustion of females because of reinfection by triungulins. Graphical and regression analysis of the population data (no. individuals/1 000 sweeps) show that, for P. costalis, parasitism by H. pontifex is density dependent and the chief regulating factor. Rainfall 58–64 days before sampling also was correlated with P. costalis density, but multiple regression analysis showed it to be insignificant.


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