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1.
Int J Hyperthermia ; 3(3): 217-33, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3116125

RESUMO

EMT6 multicellular spheroids invariably swell by 10 to 50 per cent after incubation at 43 to 45 degrees C for 1 h. Both scanning electron and optical microscopy reveal morphological alterations particularly in the outer region of the spheroids. While the control cells are contiguous to one another and tightly held to the spheroid body, the heated spheroids exhibit partially disrupted contacts among cells. Measurements of intercellular volume and water volume of spheroids with labelled water and inulin show that changes in the spheroid volume are not due to an increase in cell volume, but that they can be explained by a 60-100 per cent increase in the intercellular space within a spheroid. Continuous observation of individual spheroids heated to 43-45 degrees C shows loss of adhesion of cells in the outer region and even detachment of a few surface cells. This 'melting' of the spheroid surface appears to result from a disorder in the extracellular material. Treatment with cell swelling agents such as hypotonic solution, ouabain, excess extracellular potassium ions, or ionophore nigericin, K+/H+ exchanger, each separately causes the spheroids to swell at the control temperature. On the other hand, A23187, Ca2+ ionophore, causes shrinkage of the spheroids. Thus, under hyperthermia, the volume of spheroids increases due to the disruption in the cell organization in their outer region.


Assuntos
Hipertermia Induzida , Células Tumorais Cultivadas/citologia , Calcimicina/farmacologia , Linhagem Celular , Ionóforos/farmacologia , Microscopia Eletrônica de Varredura , Nigericina/farmacologia , Ouabaína/farmacologia , Células Tumorais Cultivadas/ultraestrutura
2.
J Biochem Biophys Methods ; 12(3): 123-33, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3086420

RESUMO

In numerous cellular studies, cells labeled with radioisotopes have been separated from the labeling medium by an aqueous solution in order to determine the quantity of internalized labels; however, the aqueous wash tends to remove significant labeling from the cells. Therefore, in order to preserve all of the internalized labels, non-aqueous medium such as silicone fluids may be used. The termination of the labeling is achieved in the silicone method when, upon centrifugation, the cells separate from the medium and enter the silicone fluid to sediment to the tube bottom. This sedimentation of cells placed above a layer of silicone fluid exhibits a critical dependence on the centrifugal force, and gives rise to an uncertainty of only 2 s in determining the time of separation of cells from the medium using General Electric F-50 silicone fluid and a modified Beckman J2-21 centrifuge. It is therefore possible to determine the kinetics of incorporation of labeled amino acids into intracellular pools and proteins. In particular, since this silicone wash method determines the size of the total pool and the aqueous wash method determines the size of the acid-extractable pool, the simultaneous measurements of the size of both pools leads to the determination of the kinetics of labeling of the free amino acid pool. Among many possible applications and extensions of these methods, the studies of formation of intracellular pools and relations among different pools of transported molecules, such as water and amino acids, appear promising.


Assuntos
Aminoácidos/metabolismo , Líquidos Corporais/metabolismo , Líquido Intracelular/metabolismo , Silicones , Animais , Transporte Biológico Ativo , Fracionamento Celular/métodos , Células Cultivadas , Centrifugação , Espaço Extracelular/metabolismo , Cinética , Sarcoma de Mastócitos/metabolismo , Camundongos , Biossíntese de Proteínas
4.
Cell Biol Int Rep ; 7(10): 797-806, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6416687

RESUMO

When p815 mastocytoma cells are heated to 43 degrees C from 37 degrees C, pools of individual amino acids and the total amino acid pool increase significantly, the latter reaching a new plateau within 20 minutes. The increase in the total amino acid pool may reach as much as 75 mOsm per liter of cell water or 26% of the cellular osmolarity. The source of this excess amino acid is not due to an accelerated degradation of proteins, but either to the amino acids left behind by slowed protein synthesis or to the accelerated transport of extracellular amino acids into the cell. The excess amino acid should increase the osmolarity and the cell volume. Evidence suggests that the cell volume increase triggers the osmoregulatory process to reduce the contents of major ions.


Assuntos
Aminoácidos/metabolismo , Temperatura Alta , Sarcoma de Mastócitos/metabolismo , Proteínas de Neoplasias/metabolismo , Animais , Permeabilidade da Membrana Celular , Células Cultivadas , Sarcoma de Mastócitos/patologia , Camundongos , Equilíbrio Hidroeletrolítico
9.
J Oral Surg ; 38(8): 617-8, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6930465

RESUMO

The clinical radiologic, and histopathologic findings of an extremely large traumatic bone cyst have been described. The review of literature, theories of origin, and management of the traumatic cyst have been briefly discussed.


Assuntos
Cistos Ósseos/diagnóstico , Doenças Mandibulares/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade
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