scholarly journals Phenotypical expression of reduced mobility during limb ontogeny in frogs: the knee-joint case

2015 ◽  
Author(s):  
Maria Laura Ponssa ◽  
Virginia Abdala
Keyword(s):  
Knee Joint ◽  
Normal Development ◽  
Development Studies ◽  
Epigenetic Factors ◽  
Skeletal System ◽  
Joint Tissue ◽  
Joint Development ◽  
Stage Of Development ◽  
Developmental Effects ◽  
Reduced Mobility

Movement is one of the most important epigenetic factors for normal development of the muscle-skeletal system, particularly during genesis and joint development. Studies regarding alterations to embryonic mobility, performed on anurans, chickens and mammals, report important phenotypical similarities as a result of the reduction or absence of this stimulus. The precise stage of development at which the stimulus modification generates phenotypic modifications however, is yet to be determined. In this work we explore whether the developmental effects of abnormal mobility can appear at any time during development or whether they begin to express themselves in particular phases of tadpole ontogeny. We conducted five experiments that showed that morphological abnormalities are not visible until Stages 40–42. Morphology in earlier stages remains normal, probably due to the fact that the bones/muscles/tendons have not yet developed and therefore are not affected by immobilization. These results suggest the existence of a specific period of phenotypical expression in which normal limb movement is necessary for the correct development of the joint tissue framework.

scholarly journals Phenotypical expression of reduced mobility during limb ontogeny in frogs: the knee-joint case

2015 ◽  
Author(s):  
Maria Laura Ponssa ◽  
Virginia Abdala
Keyword(s):  
Knee Joint ◽  
Normal Development ◽  
Development Studies ◽  
Epigenetic Factors ◽  
Skeletal System ◽  
Joint Tissue ◽  
Joint Development ◽  
Stage Of Development ◽  
Developmental Effects ◽  
Reduced Mobility

Movement is one of the most important epigenetic factors for normal development of the muscle-skeletal system, particularly during genesis and joint development. Studies regarding alterations to embryonic mobility, performed on anurans, chickens and mammals, report important phenotypical similarities as a result of the reduction or absence of this stimulus. The precise stage of development at which the stimulus modification generates phenotypic modifications however, is yet to be determined. In this work we explore whether the developmental effects of abnormal mobility can appear at any time during development or whether they begin to express themselves in particular phases of tadpole ontogeny. We conducted five experiments that showed that morphological abnormalities are not visible until Stages 40–42. Morphology in earlier stages remains normal, probably due to the fact that the bones/muscles/tendons have not yet developed and therefore are not affected by immobilization. These results suggest the existence of a specific period of phenotypical expression in which normal limb movement is necessary for the correct development of the joint tissue framework.

scholarly journals Phenotypical expression of reduced mobility during limb ontogeny in frogs: the knee-joint case

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1730 ◽  
Author(s):  
Maria Laura Ponssa ◽  
Virginia Abdala
Keyword(s):  
Knee Joint ◽  
Musculoskeletal System ◽  
Normal Development ◽  
Development Studies ◽  
Epigenetic Factors ◽  
Joint Tissue ◽  
Joint Development ◽  
Stage Of Development ◽  
Developmental Effects ◽  
Reduced Mobility

Movement is one of the most important epigenetic factors for normal development of the musculoskeletal system, particularly during genesis and joint development. Studies regarding alterations to embryonic mobility, performed on anurans, chickens and mammals, report important phenotypical similarities as a result of the reduction or absence of this stimulus. The precise stage of development at which the stimulus modification generates phenotypic modifications however, is yet to be determined. In this work we explore whether the developmental effects of abnormal mobility can appear at any time during development or whether they begin to express themselves in particular phases of tadpole ontogeny. We conducted five experiments that showed that morphological abnormalities are not visible until Stages 40–42. Morphology in earlier stages remains normal, probably due to the fact that the bones/muscles/tendons have not yet developed and therefore are not affected by immobilization. These results suggest the existence of a specific period of phenotypical expression in which normal limb movement is necessary for the correct development of the joint tissue framework.

Inflammatory effects on knee joint tissue by indoxyl sulfate

2013 ◽  
Author(s):  
Ya-Yun Chen ◽  
Herng-Sheng Lee ◽  
Yu-Juei Hsu
Keyword(s):  
Knee Joint ◽  
Indoxyl Sulfate ◽  
Joint Tissue

In Vitro Fertilization of Bovine Oocytes Matured In Vitro

1997 ◽  
Vol 1987 ◽  
pp. 28-28
Author(s):  
K.H. Lu ◽  
I. Gordon ◽  
M.P. Boland ◽  
T.F. Crosby
Keyword(s):  
Embryo Transfer ◽  
Normal Development ◽  
Present Report ◽  
Blastocyst Stage ◽  
Laboratory Procedure ◽  
Commercial Exploitation ◽  
Vitro Fertilization ◽  
Stage Of Development ◽  
Bovine Oocytes

The development of an efficient laboratory procedure which would enable cattle ovarian oocytes to be matured in vitro, fertilized and cultured in vitro to the blastocyst stage of development could have important practical and scientific implications. The commercial exploitation of certain embryo transfer techniques applicable in cattle (eg., twinning by embryo transfer) might be facilitated by the development of such a procedure and there would be many advantages to having a cheap source of embryos available for research purposes. The present report deals with some of the studies recently carried out in this laboratory aimed at utilising follicular oocytes recovered from the ovaries of cattle slaughtered for beef at the abattoir. Such studies have been undertaken over a period of almost twenty years, starting with the work of Sreenan (1968)* but it now realised that the oocytes of farm mammals are incapable of normal development until after the completion of complex changes during maturation.

Analysis of Single Actuator for Rehabilitation Device of Leg Weakness

2013 ◽  
Vol 465-466 ◽  
pp. 1021-1025 ◽  
Author(s):  
Khairul Fadzli Samat ◽  
Mohamed Hussein ◽  
M.R. Safizadeh
Keyword(s):  
Knee Joint ◽  
Direct Current ◽  
Kinematic Analysis ◽  
Dc Motor ◽  
Knee Joints ◽  
Cam Mechanism ◽  
Stage Of Development ◽  
Initial Stage ◽  
Walking Motion ◽  
Leg Weakness

In this paper, the development of rehabilitation device for patients who encounter walking weakness due to post-stroke effect is presented. The kinematic analysis was carried out in the initial stage of development in order to have an efficient mechanism. As guide to design the device, the walking motion of healthy physical subject for speed of 1 km/h was used and subsequently a mechanism was designed to create similar walking motion. The device functions to inculcate the movement of thigh and calf through appropriate rotation of hip and knee. A single actuator of direct current (DC) motor is used to actuate the rotation of the hip and the knee joints mechanism. The kinematic analysis of constructed device has been performed and the results conformed the functionality of the suggested mechanism. The fabricated prototype proves the combination of DC motor and cam mechanism can actuated the movement of hip and knee joint simultaneously and subsequently reduced the power consumption.

scholarly journals The morphological state of the knee joint tissue of rats in a modelled endoprosthetics of the tibia

2009 ◽  
Vol 0 (3) ◽  
pp. 70
Author(s):  
Svitlana Malyshkina ◽  
Olga Nikolchenko ◽  
Stanislav Shevchenko ◽  
Vitaliy Baev
Keyword(s):  
Knee Joint ◽  
Joint Tissue ◽  
Morphological State

Effect of stage of development and pre-natal nutrition on hoof characteristics of fetal sheep

2000 ◽  
Vol 2000 ◽  
pp. 128-128
Author(s):  
K. Howard ◽  
M. Birnie ◽  
H. Galbraith
Keyword(s):  
Time Course ◽  
Soft Tissues ◽  
Maternal Nutrition ◽  
Normal Development ◽  
Production Systems ◽  
Farm Animals ◽  
Fetal Sheep ◽  
Stage Of Development ◽  
Welfare Problem ◽  
And Function

Lameness is a major welfare problem in farm animals and poor hoof (claw) health frequently causes painful lesions. Such lesions frequently arise from damage to the underlying dermal and epidermal soft tissues causing impaired production of the horn on the external surface of the claw (Budras et al., 1998) Precisely timed interactions between embryonic dermis and epidermis, are essential for normal development and function in other integumental tissues such as the hair follicle (Galbraith, 1998), but have not been confirmed for claw tissue. The time course of development of cellular and extra-cellular structures has not been described, nor has the question of whether fetal prenatal claw development may be affected by undernutrition of the ewe such as frequently occurs in extensive production systems. The aims of the study were to investigate external physical dimensions and internal cellular development of fetal claws and how these may be influenced by stage of gestation and maternal nutrition.

Combinatorial control of cell differentiation by cAMP and DIF-1 during development of Dictyostelium discoideum

Development ◽  
1990 ◽  
Vol 110 (3) ◽  
pp. 977-984 ◽  
Author(s):  
M. Berks ◽  
R.R. Kay
Keyword(s):  
Cell Differentiation ◽  
Normal Development ◽  
Specific Effect ◽  
Cell Types ◽  
Signal Molecules ◽  
Stage Of Development ◽  
Combinatorial Control ◽  
Cell Type Specific ◽  
Significant Pathway ◽  
Mrna Markers

At least three distinct types of cell arise from a population of similar amoebae during Dictyostelium development: prespore, prestalk A and prestalk B cells. We report evidence suggesting that this cellular diversification can be brought about by the combinatorial action of two diffusible signals, cAMP and DIF-1. Cells at different stages of normal development were transferred to shaken suspension, challenged with various combinations of signal molecules and the expression of cell-type-specific mRNA markers measured 1–2 h later. pDd63, pDd56 and D19 mRNAs were used for prestalk A, prestalk B and prespore cells respectively. We find the following results. (1) Cells first become responsive to DIF-1 for prestalk A differentiation and to cAMP for prespore differentiation at the end of aggregation, about 2 h before these cell types normally appear. (2) At the first finger stage of development, when the rate of accumulation of the markers is maximal, the expression of each is favoured by a unique combination of effectors: prespore differentiation is stimulated by cAMP and inhibited by DIF-1; prestalk A differentiation is stimulated by both cAMP and DIF-1 and prestalk B differentiation is stimulated by DIF-1 and inhibited by cAMP. (3) Half-maximal effects are produced by 10–70 nM DIF-1, which is in the physiological range. (4) Ammonia and adenosine, which can affect cell differentiation in other circumstances, have no significant pathway-specific effect in our conditions. These results suggest that cell differentiation could be brought about in normal development by the localized action of cAMP and DIF-1.

Timekeeping by frog embryos, in normal development and after heat shock

Development ◽  
1987 ◽  
Vol 99 (1) ◽  
pp. 41-49
Author(s):  
T. Elsdale ◽  
D. Davidson
Keyword(s):  
Heat Shock ◽  
Normal Development ◽  
Rate Of Development ◽  
Stage Of Development ◽  
Heat Shocks ◽  
The Moment ◽  
The Postponement ◽  
Fixed Period

(1) Timekeeping refers to the uniformity of development in time. The precision of timekeeping is measured by the extent to which embryos, within an initially synchronous population, come to diverge in the course of their development. (2) Divergence is measured as the variation in the stage of development reached between embryos allowed to develop for a fixed period of time. The lower the variation the better the timekeeping. (3) Divergence among frog embryos that started development at the same time is hardly measurable after approx. 100 h of development. This striking uniformity indicates good timekeeping. (4) Timekeeping is not impaired among the survivors following heat shocks that retard development and disturb and curtail morphogenesis. (5) The immediate effect of heat shock is a stoppage of development, the duration of which is the same for all embryos in the same treatment batch. The embryos react to heat shock by rescheduling their development with the interpolation of a rest, the duration of which is controlled to the same precision as normal development. The postponement of development, without impairment of timekeeping, implies dis-engagement of the processes of morphogenesis from, and their subsequent re-engagement with, an enduring rate-determining activity unaffected by heat shock. (6) We have searched for embryos whose rate of development was disturbed by heat shock to run slower or faster than the norm. We have found none. It seems that the (temperature-compensated) rate of development is invariant up to the moment of failure, or a change is immediately lethal.

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