Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
Add more filters










Publication year range
1.
Arch Oral Biol ; 54(1): 6-11, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18814858

ABSTRACT

It has been previously reported that several doses of cyclophosphamide (CPA) reduce body weight gain, diaphyseal torsional strength and longitudinal femoral growth in the growing rat. The present study was thus designed to estimate both the initial and the possible long-term effects of CPA treatment, by analyzing mandibular dimensions and biomechanical performance of the bone in adulthood in rats treated with the drug around weaning. Female Sprague-Dawley rats (N=20), 26 d of age, received 100mg/kg of CPA by the intraperitoneal route during days 0, 7 and 21 of the experimental period. Controls (C) received saline. Groups of rats were sacrificed at day 28 to estimate initial changes induced by the drug and on day 126 in order to determine long-term effects. The dimensions of the excised mandibles were measured directly between anatomical points; the geometry and material biomechanical quality of mandibular bone were assessed using a three-point bending mechanical test in an Instron Universal Testing Machine model 4442. CPA reduced body weight, body length and mandibular size (posterior part of the bone) significantly, when the parameters were measured at day 28. They did not recover with time, which means that catch-up growth did not occur and that the overall growth of the body was permanently affected by the drug. CPA treatment was also associated with a marked depression of the natural increase in the mandibular bone mass (cross-sectional area). The bending cross-sectional moment of inertia of the fracture sections (xCSMI) was also negatively affected by treatment. Significant decreases of both ultimate load and stiffness were also observed. The above structural parameters did not recover enough with time to attain control values at the end of the study. The intrinsic stiffness (E) of the mandibular bone was not affected by treatment. These findings suggest that CPA treatment during early postnatal life causes permanent changes in mandibular morphology and affects the adaptation of mandibular bone architecture to body growth, thus not allowing complete compensation at the end of the study because of an inadequate distribution of the resistive material through its cross-section rather than a qualitative impairment of cortical bone.


Subject(s)
Antineoplastic Agents, Alkylating/adverse effects , Bone Density/drug effects , Cyclophosphamide/adverse effects , Mandible/drug effects , Age Factors , Animals , Animals, Newborn , Elasticity/drug effects , Female , Growth Disorders/chemically induced , Mandible/anatomy & histology , Organ Size/drug effects , Rats , Rats, Sprague-Dawley
2.
Buenos Aires; C.T.M; 1987. 192 p. ilus, tab.
Monography in Spanish | BINACIS | ID: biblio-1192982

ABSTRACT

Excitabilidad y neurona. Potencial de membranas y señales. Transmisión sinóptica. Fisiología de los órganos efectores: músculos. Control del músculo esquelético, cardíaco y liso, células secretorias externas: sistema nervioso autónomo. Fisiología de las sensaciones, sentidos químicas, sensación de posición mandibular. Actividad eléctrica de la corteza central. Bases neurofisiológicas del comportamiento instintivo y de las emociones. Sistema límbico


Subject(s)
Humans , Musculoskeletal Physiological Phenomena , Nervous System Physiological Phenomena , Membrane Potentials , Sensation/physiology , Synaptic Transmission , Neuromuscular Junction , Neurophysiology
3.
Buenos Aires; C.T.M; 1987. 192 p. ilus, Tab. (66400).
Monography in Spanish | BINACIS | ID: bin-66400

ABSTRACT

Excitabilidad y neurona. Potencial de membranas y señales. Transmisión sinóptica. Fisiología de los órganos efectores: músculos. Control del músculo esquelético, cardíaco y liso, células secretorias externas: sistema nervioso autónomo. Fisiología de las sensaciones, sentidos químicas, sensación de posición mandibular. Actividad eléctrica de la corteza central. Bases neurofisiológicas del comportamiento instintivo y de las emociones. Sistema límbico


Subject(s)
Humans , Nervous System Physiological Phenomena , Membrane Potentials , Synaptic Transmission , Sensation/physiology , Neurophysiology , Neuromuscular Junction
SELECTION OF CITATIONS
SEARCH DETAIL
...