scholarly journals Hypothetical lung structure of Brachiosaurus (Dinosauria: Sauropoda) based on functional constraints

Fossil Record ◽  
1999 ◽  
Vol 2 (1) ◽  
pp. 75-79 ◽  
Author(s):  
S. F. Perry ◽  
C. Reuter
Keyword(s):  
Gas Exchange ◽  
Body Wall ◽  
Structural Type ◽  
The Body ◽  
Dorsal Margin ◽  
Functional Constraints ◽  
Ventral Part ◽  
Lung Inflation ◽  
Large Size ◽  
Lung Structure

Comparison of avian and crocodylian lung structure suggests a basic archosaurian structural type, consisting of four rows of chambers that radiate independently from an intrapulmonary bronchus. The later structure is cartilage-reinforced cranially. Caudally, the cartilage reinforcement diminishes and the radiating pattern of tubular chambers becomes irregular. The presence of extensive pneumatic spaces in the dorsal vertebrae combined with the extremely large size of <i>Brachiosaurus</i> suggests that the dorsal margin of the lungs was strongly attached to the body wall, thus restricting lung inflation in this region. By analogy with similarly structured testudine lungs, it is highly probable that the ventral part of the very large and cavernous lungs consisted of sac-like chambers, which acted as air reservoirs and also ventilated the gas exchange tissue, which was concentrated dorsally. <br><br> Die Strukturen der Vogel- und der Krokodillunge deuten auf einen basalen Bauplan der Archosaurierlunge hin, der aus vier Reihen von Kammern besteht, die von einem intrapulmonalen Bronchus entspringen. Dieser ist cranial knorpelig verstärkt. Caudal vermindert sich die knorpelige Verstärkung und das Verteilungsmuster der Kammern wird ungleichmäßig. Die Anwesenheit von pneumatischen Räumen in den Wirbelkörpern und die extreme Größe von <i>Brachiosaurus</i> deuten daraufhin, daß der dorsale Bereich der Lunge mit der Körperwand verbunden war. Dies schränkte die Belüftung der Lunge in dieser Region ein. In Analogie zu den ähnlich strukturierten Schildkrötenlungen ist es höchst wahrscheinlich, daß der ventrale Teil der sehr großen Lungen aus sackartigen Kammern bestand, die als Luftreservoir dienten und das dorsal liegende Gasaustauschgewebe ventilierten. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.1999.4860020104" target="_blank">10.1002/mmng.1999.4860020104</a>

The morphology of the British Prostriata with particular reference to Ixodes hexagonus Leach. II

Parasitology ◽  
1953 ◽  
Vol 42 (3-4) ◽  
pp. 161-186 ◽  
Author(s):  
D. R. Arthur
Keyword(s):  
Developmental Stages ◽  
Egg Laying ◽  
The Body ◽  
Dorsal Margin ◽  
Leg Length ◽  
Large Size ◽  
Attachment Sites ◽  
Wide Range ◽  
Primitive Condition ◽  
Basis Capituli

The palps of all stages of Ixodes trianguliceps are provided with a ventral plate below the basal article; formerly this plate was thought to be the first palpal article. This article in the larva and nymph is produced forward into a spur, but in the female tick this spur is incorporated into the basis capituli as the sella. The hypostomes of I. trianguliceps and I. canisuga are redescribed to clear up existing inaccuracies.Ticks in which the rostrum does not extend beyond the apex of the first palpal article are found on birds, and this probably represents a primitive condition. Those with palpal spurs, which may or may not be fused with the basis capituli, are found on birds (not in Britain) or on mammals of the mouse size group, and those where the rostrum is produced beyond the first palpal article occur on a wide range of large and small animals. The longer and more heavily toothed digits of ticks appear to be associated with a wide host range and vice versa. The structure of the digit may also influence the choice of attachment sites by ticks on their hosts because the microstructure of the skin varies in different parts.Variations in size and form of the scuta of some British ticks are described, and the mean growth rate is ascertained from this data. The information shows that the material of I. ricinus and I. hexagonus is homogeneous, and that specific differences occur in size, shape, the position and type of dermal ducts and in the relation between scutal and alloscutal bristles.The morphology of Gené's organ in I. hexagonus is described. It consists of a basal sac-like portion surmounted by four horns and lined with a cuticle beneath an epithelium. The gland is a proliferation of the epithelium and located near the bifurcation of the base into the horns. A watery refractile fluid, secreted by the gland, accumulates between the epidermis and the cuticle in the horn-like extensions. Proximally the thick endocuticle and epidermis lie close together, and two cuticularized rods penetrate the endocuticle for about half-way along the stalk. The rods arise from the postero-dorsal margin of the basis capituli. Muscles, arising from the free ends of the rods, pass back to near the hind-margin of the scutum; they retract the basis capituli after egg laying and indirectly assist in the retraction of Gené's organ. A suggested mechanism for everting Gené's organ in I. hexagonus is outlined.During feeding the opisthosomatic cuticle of all developmental stages of the tick is much stretched. In the larva, where the cuticle is thin, this is effected by the flattening of the epicuticular pleats, but nymphs and females have, in addition, two longitudinal folds alongside the body which stretch to a far greater extent than do the epicuticular pleats. Similar folds are present between the hard ventral plates and the scutum and between the epimeral and median plates in the male. Coupled with the large size of the male digit, this suggests that morphologically, at least, males can imbibe blood.The growth of the leg segments of I. hexagonus is not constant from stage to stage, and as a result the shortest ‘leg-length’ of the female exceeds the longest ‘leg-length’ of the male.

Lymphangiomatosis of the Body Wall: A Report of Two Cases Associated with Chylothorax and Fatal Outcome

1997 ◽  
Vol 17 (4) ◽  
pp. 617-624 ◽  
Author(s):  
Philippe Moerman ◽  
Chris Van Geet ◽  
Hugo Devlieger
Keyword(s):  
Body Wall ◽  
Fatal Outcome ◽  
The Body

scholarly journals A screen for genetic loci required for body-wall muscle development during embryogenesis in Caenorhabditis elegans.

Genetics ◽  
1994 ◽  
Vol 137 (2) ◽  
pp. 483-498
Author(s):  
J Ahnn ◽  
A Fire
Keyword(s):  
Caenorhabditis Elegans ◽  
Myosin Heavy Chain ◽  
Muscle Cell ◽  
Heavy Chain ◽  
Body Wall ◽  
Muscle Development ◽  
Contractile Function ◽  
The Body ◽  
Body Wall Muscle ◽  
Genetic Loci

Abstract We have used available chromosomal deficiencies to screen for genetic loci whose zygotic expression is required for formation of body-wall muscle cells during embryogenesis in Caenorhabditis elegans. To test for muscle cell differentiation we have assayed for both contractile function and the expression of muscle-specific structural proteins. Monoclonal antibodies directed against two myosin heavy chain isoforms, the products of the unc-54 and myo-3 genes, were used to detect body-wall muscle differentiation. We have screened 77 deficiencies, covering approximately 72% of the genome. Deficiency homozygotes in most cases stain with antibodies to the body-wall muscle myosins and in many cases muscle contractile function is observed. We have identified two regions showing distinct defects in myosin heavy chain gene expression. Embryos homozygous for deficiencies removing the left tip of chromosome V fail to accumulate the myo-3 and unc-54 products, but express antigens characteristic of hypodermal, pharyngeal and neural development. Embryos lacking a large region on chromosome III accumulate the unc-54 product but not the myo-3 product. We conclude that there exist only a small number of loci whose zygotic expression is uniquely required for adoption of a muscle cell fate.

scholarly journals Cloning and sequencing of cDNA of Sarcophaga peregrina humoral lectin induced on injury of the body wall.

1985 ◽  
Vol 260 (22) ◽  
pp. 12228-12233 ◽  
Author(s):  
H Takahashi ◽  
H Komano ◽  
N Kawaguchi ◽  
N Kitamura ◽  
S Nakanishi ◽  
...  
Keyword(s):  
Body Wall ◽  
The Body ◽  
Cloning And Sequencing

scholarly journals Mutations Affecting Nerve Attachment of Caenorhabditis elegans

Genetics ◽  
2001 ◽  
Vol 157 (4) ◽  
pp. 1611-1622 ◽  
Author(s):  
Go Shioi ◽  
Michinari Shoji ◽  
Masashi Nakamura ◽  
Takeshi Ishihara ◽  
Isao Katsura ◽  
...  
Keyword(s):  
Caenorhabditis Elegans ◽  
Nerve Cord ◽  
Ventral Nerve Cord ◽  
Body Wall ◽  
The Body ◽  
Genetic Loci ◽  
Muscle Attachment ◽  
C Elegans ◽  
Ventral Cord ◽  
Excretory Canal

Abstract Using a pan-neuronal GFP marker, a morphological screen was performed to detect Caenorhabditis elegans larval lethal mutants with severely disorganized major nerve cords. We recovered and characterized 21 mutants that displayed displacement or detachment of the ventral nerve cord from the body wall (Ven: ventral cord abnormal). Six mutations defined three novel genetic loci: ven-1, ven-2, and ven-3. Fifteen mutations proved to be alleles of previously identified muscle attachment/positioning genes, mup-4, mua-1, mua-5, and mua-6. All the mutants also displayed muscle attachment/positioning defects characteristic of mua/mup mutants. The pan-neuronal GFP marker also revealed that mutants of other mua/mup loci, such as mup-1, mup-2, and mua-2, exhibited the Ven defect. The hypodermis, the excretory canal, and the gonad were morphologically abnormal in some of the mutants. The pleiotropic nature of the defects indicates that ven and mua/mup genes are required generally for the maintenance of attachment of tissues to the body wall in C. elegans.

The cuticle of adultNippostrongylus brasiliensis

Parasitology ◽  
1965 ◽  
Vol 55 (1) ◽  
pp. 173-181 ◽  
Author(s):  
D. L. Lee
Keyword(s):  
Electron Microscope ◽  
Body Wall ◽  
Technical Assistance ◽  
Cortical Layer ◽  
The Body ◽  
Collagen Fibrils ◽  
Intestinal Cells ◽  
Nippostrongylus Brasiliensis ◽  
Normal Appearance

The cuticle of adults ofNippostrongylus brasiliensishas been described using histological, histochemical and ultrastructural techniques.The cuticle has the following layers: an outer triple-layered membrane; a single cortical layer; a fluid-filled layer which is traversed by numerous collagen fibrils; struts which support the fourteen longitudinal ridges of the cuticle and which are suspended by collagen fibrils in the fluid-filled layer; two fibre layers, each layer apparently containing three layers of fibres; and a basement lamella.The fluid-filled layer contains haemoglobin and esterase.The muscles of the body wall are attached to either the basement lamella or to the fibre layers of the cuticle.The mitochondria of the hypodermis are of normal appearance.The longitudinal ridges of the cuticle appear to abrade the microvilli of the intestinal cells of the host.Possible functions of the cuticle are discussed.I wish to thank Dr P. Tate, in whose department this work was done, for helpful suggestions and criticism at all stages of this work, and Mr A. Page for technical assistance. I also wish to thank Professor Boyd for permission to use the electron microscope in the Department of Anatomy.

Lymphangiomatosis of the Body Wall: A Report of Two Cases Associated with Chylothorax and Fatal Outcome

1997 ◽  
Vol 17 (4) ◽  
pp. 617-624 ◽  
Author(s):  
Philippe Moerman ◽  
Chris Van Geet ◽  
Hugo Devlieger
Keyword(s):  
Body Wall ◽  
Fatal Outcome ◽  
The Body
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