The effects of 1,25-dihydroxycholecalciferol on embryonic bone in vitro: A biochemical and histological study

1978 ◽  
Vol 25 (1) ◽  
pp. 111-118 ◽  
Author(s):  
M. P. M. Herrmann-Erlee ◽  
P. J. Gaillard
Keyword(s):  
Histological Study ◽  
Embryonic Bone

scholarly journals Experiments on skeletal growth and development in vitro in relation to the problem of avian phokomelia

1935 ◽  
Vol 118 (807) ◽  
pp. 133-154 ◽  
Keyword(s):  
Bone Formation ◽  
Bone Growth ◽  
Histological Study ◽  
Detailed Comparison ◽  
Specific Gene ◽  
Body Parts ◽  
Continue Development ◽  
Hatching Time ◽  
Stage Of Development

The experiments to be reported in the following pages were suggested by observations made by one of us on the so-called Creeper fowl. Creeper chickens are characterized by a disproportionate shortness of the long bones of the extremities. Histological study has shown that Creeper chickens belong in the same category as the disproportionate dwarfism of mammals known as chondrodystrophy or achondroplasia (Landauer, 1931) . The Creeper characters are inherited as a Mendelian dominant and are lethal in homozygous condition (Landauer and Dunn, 1930). Homozygous Creeper embryos generally die after about 72 hours of incubation, but in rare cases they survive beyond this stage and continue development up to nearly hatching time. These late stages of homozygous Creeper embryos exhibit striking malformations of the extremities which are known as phokomelia (Landauer, 1933). A study of the early embryonic development of homozygous Creeper embryos (Landauer, 1932) led to the conclusion that the effects of the Creeper mutation are not brought about by specific gene action on those body parts which later show deformities, but by a general retardation of body growth at a definite stage of development. This conclusion was strengthened by a detailed comparison of embryonic and post-natal bone growth in heterozygous Creeper and normal chickens (Landauer, 1934). All evidence which so far has been obtained in this work points to the conclusion that the characteristic traits of heterozygous as well as homozygous Creeper chicks are produced by an unspecific retardation of development at a time when formation of the buds of the extremities (and of the head which in homozygous embryos also shows deformities later on) are proceeding at a particularly rapid rate, thereby causing specific disturbances in the differentiation of these parts. It seemed to us that it should be possible to put these conclusions to an experimental test. The most promising way of approach appeared to be an attempt to produce in vitro the extreme abnormalities of bone formation shown by the extremities of phokomelic homozygous Creeper embryos. These abnormalities chiefly consist in (1) a general retardation of cartilage differentiation; (2) lack of bone formation; and (3) frequent partial fusion of ulna and radius on the one hand, tibia and fibula on the other, or presence of only one bone in these segments instead of two.

Investigation of the Thermal and Injury Behavior During Microwave Thermal Therapy of Porcine Kidney

2002 ◽  
Author(s):  
Xiaoming He ◽  
Shawn Mcgee ◽  
James E. Coad ◽  
Paul A. Iaizzo ◽  
David J. Swanlund ◽  
...  
Keyword(s):  
Thermal Model ◽  
Histological Study ◽  
Kidney Cortex ◽  
Cellular Injury ◽  
Bioheat Equation ◽  
Tissue Slices ◽  
Thermal Histories ◽  
Microwave Probe

In this paper, we report on the characterization of microwave therapy of normal porcine kidneys both in vitro and in vivo. This technology is being developed for eventual use in the treatment of small renal cell carcinoma (RCC) by minimally invasive procedures. During experiments, microwave energy was applied through an interstitial microwave probe (Urologix, Plymouth, MN) to the kidney cortex with occasional involvement of the kidney medulla. The thermal histories at several locations were recorded. After treatment, the kidneys were bisected and small tissue slices were cut out at approximately the same depth as the thermal probes. The tissue slices were further processed for histological study. Both cellular injury and the area of microvascular stasis were quantitatively evaluated by histology. Absolute rate kinetic models of cellular injury and vascular stasis were developed and fit to this data. A 3-D finite element thermal model based on the Pennes Bioheat equation was developed and solved using a commercial software package (ANSYS, V5.7). The Specific Absorption Rate (SAR) of the microwave probe was measured experimentally in tissue equivalent gel-like solution. The thermal model was first validated by the measured in vitro thermal histories. It was then used to determine the blood perfusion term in vivo.

Comparative Physiology of the Vertebrate Autonomic Nervous System

1963 ◽  
Vol 40 (3) ◽  
pp. 421-436
Author(s):  
G. BURNSTOCK ◽  
G. CAMPBELL
Keyword(s):  
Nerve Stimulation ◽  
Histological Study ◽  
Circular Muscle ◽  
Vascular Supply ◽  
Evolutionary Significance ◽  
Blocking Agents ◽  
Pelvic Nerves ◽  
Drug Actions ◽  
Stimulation Of

1. A histological study of the structure of the urinary bladder of the ringtail possum has been made. The innervation of the bladder has been studied in vitro, using the technique of analytical pharmacology. 2. The bladder has well-defined inner longitudinal and outer circular muscle layers. Nerves supplying the bladder are found both in the pelvic nerves and in the vesical nerves which run with the vascular supply of the bladder fundus. Ganglia have been demonstrated along the trunks of the vesical nerves and also aggregated at the bladder neck. 3. The response of the bladder to stimulation of either nerve supply in situ or in vitro is always a simultaneous contraction of both longitudinal and circular muscles. Inhibitory responses to nerve stimulation have never been observed. The optimal frequency for stimulation of these nerves at 30° C. is 50 pulses/sec. 4. The bladder is contracted by ACh and 5-hydroxytryptamine, but is relaxed by adrenaline, noradrenaline and histamine. 5. The response to nerve stimulation is reduced by atropine and potentiated by eserine. Adrenergic blocking agents do not affect the nerve-mediated response unless they also affect the response to applied ACh in a similar manner. 6. Ganglionic blocking agents, in concentrations which do not reduce the response to ACh, cause up to a 40% reduction of the response to stimulation of either the vesical or the pelvic nerves. 7. It is concluded that the nerve fibres supplying the possum bladder are cholinergic, perhaps 40 % of them being stimulated pre-ganglionically. 8. The evolutionary significance of these observations is discussed. 9. Some points of pharmacological interest have been discussed in relation to drug actions on placental mammal preparations.

scholarly journals Histological study of capuchin monkey (Cebus apella) ovarian follicles

2004 ◽  
Vol 34 (3) ◽  
pp. 495-501 ◽  
Author(s):  
Sheyla Farhayldes Souza Domingues ◽  
Luiz Viana Diniz ◽  
Sonia Helena Costa Furtado ◽  
Otavio Mitio Ohashi ◽  
David Rondina ◽  
...  
Keyword(s):  
Qualitative Data ◽  
Histological Study ◽  
Follicular Development ◽  
Cebus Apella ◽  
Neotropical Primates ◽  
Preantral Follicles ◽  
Antral Follicles ◽  
The Right

The present study aimed to obtain quanti-qualitative data about the follicular ovarian population in Cebus apella females. Seven ovaries were obtained from 4 C. apella adult females. The ovaries were subjected to light microscopy. The number of preantral and antral follicles for each ovary was estimated using the Fractionator method. The preantral follicles were classified into primordial, transitional, primary and secondary follicles. Antral follicles were those that presented an antral cavity. All counted follicles were classified as normal or degenerated. The diameter of the follicles, oocytes and their nuclei were determined to accompany the follicular development. All results were represented as mean ± SE. The number of preantral follicles was 56,938 ± 21,888 and 49,133 ± 26,896 for the right and left ovaries, respectively. The percentage of normal follicles was 80 ± 4.95%. The follicular diameter ranged from 22 ± 0.5 µm to 61.2 ± 4.0 µm. Regarding the antral follicles, the number of normal and degenerate follicles per ovary were 60.0 ± 19.0 and 3 ± 1.8 follicles, respectively. The antral follicular diameter was 514.4 + 56.6 µm. In conclusion, the information obtained in this study can be used as a parameter for subsequent in vivo or in vitro studies about folliculogenesis in non-human neotropical primates of the C. apella species.

An in vitro mechanical and histological study of acute stretching on rabbit tibial nerve

1990 ◽  
Vol 8 (5) ◽  
pp. 694-701 ◽  
Author(s):  
Bj�rn L. Rydevik ◽  
Michael K. Kwan ◽  
Robert R. Myers ◽  
Richard A. Brown ◽  
Kevin J. Triggs ◽  
...  
Keyword(s):  
Tibial Nerve ◽  
Histological Study

Histological study of organogenesis in vitro from callus cultures of two Nicotiana species

1981 ◽  
Vol 59 (11) ◽  
pp. 1969-1977 ◽  
Author(s):  
V. Nuti Ronchi
Keyword(s):  
Vascular Tissue ◽  
Histological Study ◽  
Parenchyma Cell ◽  
Shoot Formation ◽  
Callus Cultures ◽  
Nicotiana Glauca ◽  
Meristematic Tissue ◽  
Nicotiana Langsdorffii ◽  
Physical And Chemical

The histological events leading to shoot formation in Nicotiana glauca and in the nontumorous Nicotiana glauca × Nicotiana langsdorffii hybrid have been studied. Organized development begins from a single vacuolated parenchyma cell which divides and precociously differentiates tracheidal cells, forming a growth center with nodular structures with xylem in the center and phloem outside. The vascular tissue is precociously separated from the surrounding callus by a layer of cells which are shown to be endodermal by position and by histochemical reactions. Further growth leads to the formation of a mound of meristematic tissue which later forms shoot apical meristems. The sequences of events are discussed in relation to other known systems of regeneration in calluses.The system described could be suitable for evaluating the effects of various physical and chemical agents on the different steps of differentiation.

A COMPARATIVE HISTOLOGICAL STUDY BETWEEN ´EMBRYOGENIC STRUCTURES´ AND ZYGOTIC EMBRYOS OF CLEMATIS HYBRIDS CULTIVATED IN VITRO

2006 ◽  
pp. 227-230 ◽  
Author(s):  
L. Arène ◽  
M. Chevalier ◽  
N. Cognée ◽  
M. Tellier ◽  
A. Cadic
Keyword(s):  
Histological Study ◽  
Zygotic Embryos

Histological studies of cellular differentiation during somatic embryogenesis of coconut plumule-derived calli

2015 ◽  
Vol 43 (3) ◽  
Author(s):  
K. Lakshmi Jayaraj ◽  
U. Bhavyashree ◽  
T.P. Fayas ◽  
K.K. Sajini ◽  
M.K. Rajesh ◽  
...  
Keyword(s):  
Somatic Embryogenesis ◽  
Somatic Embryos ◽  
Callus Formation ◽  
Histological Study ◽  
Shoot Meristem ◽  
Vascular Bundles ◽  
Histological Studies ◽  
Meristematic Cells ◽  
Meristem Development

<div><table cellspacing="0" cellpadding="0" align="center"><tbody><tr><td align="left" valign="top"><p>Since coconut is   one of the most recalcitrant species to generate <em>in vitro</em>, it is   necessary to study in detail about the cellular changes that occur during   somatic embryogenesis to enhance our knowledge about this phenomenon. In the   present study, coconut plumular tissues, the shoot meristem including leaf   primordia, were used as explants for <em>in vitro </em>regeneration studies.   Histological studies were carried out in different stages of plumule culture.   No noticeable growth was observed in 15 days old cultures. After 30 days,   meristematic cells could be identified. Abundance of meristematic cells,   foremost to the development of callus structures, was observed after 45 days.   After 75 days, globular friable calli were formed and histological studies   revealed the presence of meristematic centers which eventually formed somatic   embryos. The histological study of matured somatic embryos formed after 120   days of callus initiation showed a clear meristematic zone of parenchyma   cells, surrounded by vascular bundles. Histological studies, carried out for   certain abnormalities like compact calli, abnormal somatic embryoids with   rudimentary shoots and multiplied roots, revealed the presence of intact   cotyledonary leaves which seemed to inhibit the apical meristem development   of somatic embryoids. The presence of vascular bundles in the early stages of   callus formation might lead to the direct formation of meristemoids. These   results could aid future studies leading to enhanced control of the somatic   embryogenic process and greater efficiency of somatic embryo and plantlet   formation in coconut.</p></td></tr></tbody></table></div>

Effect of clinostat rotation on differentiation of embryonic bone in vitro

1996 ◽  
Vol 17 (6-7) ◽  
pp. 189-192 ◽  
Author(s):  
N Al-Ajmi ◽  
I.P Braidman ◽  
D Moore
Keyword(s):  
Embryonic Bone
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