Tongue Morphology in Horned Lizards (Phrynosomatidae: Phrynosoma) and its Relationship to Specialized Feeding and Diet

2021 ◽  
Vol 28 (5) ◽  
pp. 309-317
Author(s):  
Kurt Schwenk

In lizards, the tongue is joined to the mandible by the median genioglossus medialis muscle and the larger, paired genioglossus lateralis muscles. These muscles run through a frenulum and along the sides of the tongue, forming its walls. In horned lizards, however, the genioglossus lateralis muscles fail to join the tongue for most of its length, forming separate ridges evident in the floor of the mouth lateral to the body of the tongue. This unique tongue morphology co-occurs with horned lizards’ ability to consume large numbers of potentially lethal harvester ants, a diet enabled by a feeding mechanism in which ants are rapidly immobilized with strings of mucus before immediate swallowing. Circumstantial evidence implicates the unusual morphology of the genioglossus lateralis muscles in the mucus-binding system.

Author(s):  
Roy Skidmore

The long-necked secretory cells in Onchidoris muricata are distributed in the anterior sole of the foot. These cells are interspersed among ciliated columnar and conical cells as well as short-necked secretory gland cells. The long-necked cells contribute a significant amount of mucoid materials to the slime on which the nudibranch travels. The body of these cells is found in the subepidermal tissues. A long process extends across the basal lamina and in between cells of the epidermis to the surface of the foot. The secretory granules travel along the process and their contents are expelled by exocytosis at the foot surface.The contents of the cell body include the nucleus, some endoplasmic reticulum, and an extensive Golgi body with large numbers of secretory vesicles (Fig. 1). The secretory vesicles are membrane bound and contain a fibrillar matrix. At high magnification the similarity of the contents in the Golgi saccules and the secretory vesicles becomes apparent (Fig. 2).


1924 ◽  
Vol 23 (1) ◽  
pp. 106-116 ◽  
Author(s):  
Leonard P. Lockhart

1. The appearance and disappearance of typhoid bacilli in the faeces in these four cases bore no relation to changes in the diet nor to the physical state of the stools, but the later they appeared the shorter was the duration of their appearance.On the disappearance of typhoid bacilli from the stools the intestinal flora tended to become more simple.2. B. coli was the only organism invariably present at every examination.3. Streptococci were very much more abundant in the earlier stages of the disease, when milk formed the greater part of the diet, than in the later stages.4. In two cases where boils occurred on the body the causative organism had previously been isolated in large numbers from the faeces.5. With stools slightly alkaline to litmus the flora in these cases was relatively simple and fermentative in type. There is no apparent advantage, therefore, in giving a high carbohydrate diet except in cases of marked alkalinity and putrefaction.


2015 ◽  
Vol 57 (5) ◽  
pp. 421-426 ◽  
Author(s):  
Adriana Sierra Assencio Almeida BARBOSA ◽  
Suzana Madeira DIÓRIO ◽  
Silvia Cristina Barboza PEDRINI ◽  
Adauto José Ferreira NUNES ◽  
Andréa de Faria Fernandes BELONE ◽  
...  

SUMMARY The aim of this study was to evaluate the effects of the protein-calorie malnutrition in BALB/c isogenic mice infected with Lacazia loboi, employing nutritional and histopathological parameters. Four groups were composed: G1: inoculated with restricted diet, G2: not inoculated with restricted diet, G3: inoculated with regular diet, G4: not inoculated with regular diet. Once malnutrition had been imposed, the animals were inoculated intradermally in the footpad and after four months, were sacrificed for the excision of the footpad, liver and spleen. The infection did not exert great influence on the body weight of the mice. The weight of the liver and spleen showed reduction in the undernourished groups when compared to the nourished groups. The macroscopic lesions, viability index and total number of fungi found in the footpads of the infected mice were increased in G3 when compared to G1. Regarding the histopathological analysis of the footpad, a global cellularity increase in the composition of the granuloma was observed in G3 when compared to G1, with large numbers of macrophages and multinucleated giant cells, discrete numbers of lymphocytes were present in G3 and an increase was observed in G1. The results suggest that there is considerable interaction between Jorge Lobo's disease and nutrition.


limited data for the greater Townsville area (Kay et al.1996). Based on the prevalence of key vector species and their abundance and that of the viruses recovered, it was concluded that Big Bay, originally recommended as a prime site for recreational development by the Department of Local Government in 1985, actually presented lower risk than any other locality. Antill Creek also proved relatively safe in terms of mosquito-borne infections, whereas Toonpan during the wet season was a place to be avoided. Both Ross River and the environs of Townsville offered intermediate risk, the latter due to large numbers of saltmarsh mosquitoes breeding in intertidal wetlands. 9.5 Snails and swimmer’s itch Schistosome dermatitis, known as swimmer’s itch, is a common global problem for users of recreational swimming areas in water resource developments. The rash is caused by free living larvae called cercariae (Figure 9.4) of parasitic flukes which burrow into exposed parts of the body. Normally the life-cycle involves water birds such as ducks and pulmonate snails, so infection of humans is accidental. A large number of cercariae may penetrate the skin where they die but cause a localized allergic reaction in sensitized persons. In northern Australia, swimmer’s itch (Trichobilharzia) has been traditionally associated with Austropeplea (= Lymnaea) lessoni (= vinosa) although two planorbid snails, Amerianna carinata and Gyraulus stabilis, have also been identified as intermediate hosts in Lake Moondarra near Mt Isa, Queensland. Our recent data implicates Gyraulus gilberti at the Ross River dam. Snails are also commonly infected with other trematode cercariae, mainly echinostomes, strigeids/diplostomids and clinostomids.

1998 ◽  
pp. 148-148

1930 ◽  
Vol 52 (3) ◽  
pp. 385-404 ◽  
Author(s):  
Claude E. Forkner

1. The theories for the origin of monocytes from myeloblasts, lymphocytes, endothelium, macrophages, and primitive cells are reviewed and considered. 2. Monocytes in all stages of development have been demonstrated to be present constantly in large numbers in all the lymph nodes of the body, except in the large mesenteric group. 3. The relations of these cells to undifferentiated cells, lymphocytes, macrophages, plasma cells, and endothelium are described. 4. The origin of adult monocytes from primitive undifferentiated cells through the stages of monoblasts and pre-monocytes is described and illustrated. 5. The demonstration in certain lymph nodes of innumerable monocytes in all stages of development permits of a shifting of the term "monoblast" from a more or less theoretical name to its proper place as a term designating that particular cell which is derived from a primitive undifferentiated cell and which is the immediate precursor of the pre-monocyte. 6. The term "pre-monocyte" is proposed to designate the intermediate stage between the monoblast and the mature monocyte. 7. Evidence is advanced to show that monocytes are an independent strain of cells, but that under physiological conditions they may be transformed into macrophages, this representing at least one way in which the latter cells normally are produced. 8. In no organs or tissues other than in certain specific lymph nodes, chiefly the peripheral group, can one constantly find monocytes in all stages of development. 9. Developing monocytes occasionally may be found in small numbers in the spleen, mesenteric lymph nodes, Peyer's patches, subcutaneous connective tissues, lungs, and omenta of normal rabbits, but their presence is by no means constant and their numbers are insignificant in comparison with those found in the peripheral lymph nodes. 10. Monocytes and pre-monocytes do not stain by the common methods used for the demonstration of the reticulo-endothelial system and therefore must be considered for the present as independent of this system, except in so far as monocytes may be transformed into macrophages. 11. Plasma cells, stained with the supravital technique, as seen in lymph nodes, are described. No basis has been found for the theory that plasma cells and monocytes are closely related structural elements.


1997 ◽  
Vol 111 (12) ◽  
pp. 1179-1182 ◽  
Author(s):  
L. P. Miles ◽  
L. C. D. Naidoo ◽  
J. Reddy

AbstractTrue dermoid cysts of the oral cavity are rare, usually presenting as midline swellings in the floor of the mouth and occasionally elsewhere in the oral cavity. This report describes the diagnosis and management of a congenital dermoid cyst of the lateral aspect of the body of the tongue in a 10-year-old girl. The theories of the pathogenesis of this cyst during embryogenesis of the tongue are also reviewed.


1953 ◽  
Vol 97 (2) ◽  
pp. 297-314 ◽  
Author(s):  
Lucien A. Gregg ◽  
O. H. Robertson

With the purpose of ascertaining the influence exerted by the pneumococcidal activity of the blood on the course of bacteremia occurring in experimental canine pneumococcal pneumonia, a study was made of the rates at which intravenously injected pneumococci disappeared from the circulation and the shed blood of diseased dogs. Preliminary studies on normal animals showed that blood containing hundreds of thousands of pneumococci per cc. immediately after injection usually became sterile or nearly so within an hour's time. Simultaneous observations carried out on the blood in vitro showed an analogous rapid disappearance of the microorganisms, although the effect was not quite as marked. Similar tests on non-bacteremic dogs with pneumonia revealed essentially the same ability of the body to dispose of large numbers of circulating pneumococci. The shed blood likewise exhibited marked bactericidal power. The occurrence of bacteremia during pneumonia did not retard greatly the rate at which injected pneumococci disappeared from the circulation, as compared with the non-bacteremic state. After several hours the numbers of circulating microorganisms were approximately the same as prior to the intravenous injection. Blood in vitro often cleared as fully as it did in vivo over the same length of time. Studies on the role played by humoral immune substances in the bactericidal action of the blood showed that while their presence was necessary for maximum killing power, and that bacteremic blood lacking humoral immune properties was rarely capable of self-sterilization in vitro, nevertheless such blood often retained considerable bactericidal potency as shown by its ability to reduce materially the numbers of pneumococci added to it. This phenomenon is discussed. The marked pneumococcidal capacity of the blood exhibited by dogs with experimental pneumococcal pneumonia and its persistence during bacteremia suggest that this constitutes the principal mechanism for limiting the degree of blood invasion. The similarity of the findings in canine and human pneumococcal lobar pneumonia is pointed out.


1994 ◽  
Vol 22 (2) ◽  
pp. 141-147 ◽  
Author(s):  
Scott Burris

One understanding of health conceives of it as a state of freedom from pathology, achieved by an individual, through the mediation of a doctor. On this view, improvements in health flow from the application of science to specific ills of the body, and access to medical care is the chief determinant of health. This “medicalized” view of health underlies the current debate over medical care payment reform. This is the dominant way of talking about health.An alternative is the view of health commonly associated with the practice of public health. On this view, health is an attribute of communities in social and physical environments. Health takes its shape in large numbers—in morbidity and mortality statistics—and, ideally, includes not just a high level of well-being for some, but also its even distribution throughout a society. Improvements in health are seen to arise from healthful changes in the environment.


1954 ◽  
Vol 45 (4) ◽  
pp. 711-722 ◽  
Author(s):  
C. T. Lewis

The anatomy of the tarsi and pretarsi of Phormia (Protophormia) terraenovae (R.-D.); Glossina palpalis (R.-D.) and Musca domestica L. is described with particular reference to structures possibly concerned in the action of deposits of contact insecticides. The numerous setae which cover the tarsal segments are distributed in a pattern which is common to all three species. Long spines situated at the distal extremity of each segment are the points of contact with which a fly engages a surface, and which take the thrust as the fly walks. Proximal to the primary spines are two ventral rows of chemoreceptors, protected from mechanical damage by smaller spines. In addition there are lateral and dorsal rows of bristles.Contact chemoreceptors, which have been identified by experiment, are present in large numbers on the tarsi of P. terraenovae and M. domestica. Each chemoreceptor is a differentiated hollow seta possessing an extremely thin frontal membrane of cuticle, in which a lipoid layer appears to be incorporated and through which a lipoid-soluble insecticide might readily penetrate to the sensory neurocytes.Receptors of this type are also present on the tarsi of G. palpalis, though tsetse flies have not been reported to possess a tarsal gustatory sense.The pulvilli of all three species are entirely filled with viscous endocuticle and possess neither nerves, sense organs nor gland cells. The pulvilli are probably less important sites of penetration of insecticide from deposits than are the tarsel chemoreceptors, articulating membranes of setae, and intersegmental joint membranes.Measurements of nerve diameters at different parts of the tarsi are used to interpret the results of Fisher (1952) concerning the action of DDT applied to limited areas of M. domestica. It is concluded that the relative toxicity of DDT at different parts of the body may be correlated with the number of sensory nerve fibres passing close to the site of penetration, but not with the number of sensory end organs directly affected.


2016 ◽  
Vol 37 (1) ◽  
pp. 4 ◽  
Author(s):  
Matthew R Watts ◽  
Gemma Robertson ◽  
Richard Bradbury

It is estimated that over 30million people worldwide are infected by the nematode, Strongyloides stercoralis1. It is endemic in sub-tropical and tropical parts of Australia, with high rates of infection documented in some indigenous communities2. Due to the potential for chronic autoinfection, that may persist for decades, migration leads to the presence of the infection in non-endemic areas1. Transmission to humans is generally through the penetration of larvae through the skin, following contact with faecally contaminated soil1. Disease severity ranges from asymptomatic chronic carriage to an overwhelming illness, where large numbers spread throughout the body, usually triggered by immunosuppression1.


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