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1.
Carbohydr Res ; 331(1): 19-25, 2001 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-11284502

RESUMO

Two digalactosyl D-chiro-inositols and two trigalactosyl D-chiro-inositols, members of the fagopyritol A series and fagopyritol B series, were isolated from buckwheat (Fagopyrum esculentum Moench) seeds. Structures of the first three were determined by 1H and 13C NMR. Fagopyritol B2 is alpha-D-galactopyranosyl-(1-->6)-alpha-D-galactopyranosyl-(1-->2) -1D-chiro-inositol, and fagopyritol A2 is alpha-D-galactopyranosyl-(1-->6)-alpha-D-galactopyranosyl-(1-->3)- 1D-chiro-inositol. Fagopyritol A3, a trigalactosyl D-chiro-inositol, is alpha-D-galactopyranosyl-(1-->6)-alpha-D-galactopyranosyl-(1 -->6) -alpha-D-galactopyranosyl-(1-->3)- 1 D-chiro-inositol. From analysis of hydrolysis products, the second trigalactosyl D-chiro-inositol, fagopyritol B3, isalpha-D-galactopyranosyl-(1-->6)-alpha-D-galactopyranosyl-(1-->6) -alpha-D-galactopyranosyl-(1-->2)-1D-chiro-inositol.


Assuntos
Dissacarídeos/química , Fagopyrum/química , Inositol/análogos & derivados , Inositol/química , Oligossacarídeos/química , Sementes/química , Configuração de Carboidratos , Sequência de Carboidratos , Dissacarídeos/isolamento & purificação , Indicadores e Reagentes , Inositol/isolamento & purificação , Modelos Moleculares , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular
2.
Carbohydr Res ; 328(4): 623-7, 2000 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-11093720

RESUMO

The molecular structure of fagopyritol A1, a novel galactopyranosyl cyclitol from buckwheat seeds, was determined to be O-alpha-D-galactopyranosyl-(1 --> 3)-D-chiro-inositol by 1H and 13C NMR. Fagopyritol A1 is a positional isomer of fagopyritol B1 (O-alpha-D-galactopyranosyl-(1 --> 2)-D-chiro-inositol), representing a different series of fagopyritol oligomers. Trimethylsilyl derivatives of both compounds have similar mass spectra, but each may be identified by different abundance ratios of fragments with m/z 305/318 and 318/319.


Assuntos
Dissacarídeos/química , Ressonância Magnética Nuclear Biomolecular , Sequência de Carboidratos , Fagopyrum/química , Espectrometria de Massas , Sementes/química , Análise de Sequência
3.
Biochem J ; 294 ( Pt 2): 491-5, 1993 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8396915

RESUMO

Heat shock and diethyldithiocarbamate stimulate polyamine catabolism in animal cells by a mechanism involving the induction of spermidine/spermine N1-acetyltransferase (N1-SSAT) activity. Steady-state levels of RNA encoding this enzyme remain essentially unchanged during periods after these stresses when N1-SSAT activity is increased by 3.5-10-fold or more in three different cell lines of hamster and human origin. Depletion of intracellular spermidine pools by alpha-difluoromethylornithine (DFMO) inhibits stress induction of N1-SSAT activity. Exogenous spermidine can restore stress inducibility of N1-SSAT to DFMO-treated cells, and induce this enzyme activity in non-heat-shocked but polyamine-depleted cells. Acetylation at N1 suppresses the ability of spermidine to induce N1-SSAT activity, relative to this same modification at N8. Fluorinated spermidine analogues, which decrease the pKa values of the amine groups at positions 4 and 8, neither induce nor inhibit N1-SSAT activity in DFMO-treated cells. These data demonstrate that certain stresses induce N1-SSAT by a spermidine-dependent post-transcriptional mechanism. The mode of induction is affected by both the propyl and butyl moieties of spermidine.


Assuntos
Acetiltransferases/biossíntese , Temperatura Alta , Acetilação , Acetiltransferases/genética , Animais , Células CHO/metabolismo , Cricetinae , Ditiocarb/farmacologia , Eflornitina/farmacologia , Indução Enzimática/efeitos dos fármacos , Humanos , Neoplasias Pulmonares , Melanoma , RNA Mensageiro/metabolismo , Espermidina/metabolismo , Espermidina/farmacologia , Transcrição Gênica , Células Tumorais Cultivadas
4.
Life Sci ; 52(13): 1101-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8450705

RESUMO

Mice given 1% alpha-difluoromethylornithine (DFMO) in the drinking water for 5 weeks developed a hyperactive behavior characterized by uncontrolled running upon stimulation with noise. The running was followed by seizures and sometimes death. These behaviors are characteristic of audiogenic seizures. Strain differences in susceptibility to DFMO-induced audiogenic seizures were observed. The order of sensitivity to this DFMO effect was: C3HeB/FEJ = C3H/HeN > CBA/J = BALB/c. Chronic DFMO treatment was found to deplete whole brain putrescine and spermidine, but not spermine nor gamma-aminobutyric acid (GABA), in the 2 strains of mice analyzed, C3H/HeN and BALB/c. The audiogenic seizures were eliminated by pretreatment with the benzodiazepine, chlordiazepoxide (Librium) (40 mg/kg, ip) 105 minutes prior to testing for seizures.


Assuntos
Clordiazepóxido/uso terapêutico , Eflornitina/antagonistas & inibidores , Convulsões/prevenção & controle , Estimulação Acústica , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos CBA , Poliaminas/metabolismo , Convulsões/induzido quimicamente , Convulsões/etiologia , Ácido gama-Aminobutírico/metabolismo
5.
J Bone Joint Surg Br ; 74(4): 528-33, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1624510

RESUMO

We treated 63 club feet in 44 patients by a defined programme of strapping from birth followed by one of two operations performed at six weeks, either a simple calcaneal tendon lengthening or a subtalar realignment, and reviewed them prospectively. The decision as to which operation to perform was taken at four weeks after radiographic measurement of the talocalcaneal angle. All but eight patients (ten feet) were followed for a mean of 8.7 years. The overall results after calcaneal tendon lengthening were satisfactory. The re-operation rate after subtalar realignment was high (39%) due to over or undercorrection of the deformity.


Assuntos
Pé Torto Equinovaro/terapia , Criança , Pré-Escolar , Pé Torto Equinovaro/diagnóstico por imagem , Pé Torto Equinovaro/cirurgia , Feminino , Deformidades Adquiridas do Pé/etiologia , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Radiografia , Recidiva , Tendões/cirurgia
6.
Biochem J ; 280 ( Pt 2): 289-94, 1991 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-1747102

RESUMO

N1-Acetylspermidine (N1AcSpd) accumulates in late exponential phase, or after certain stresses such as heat shock, in both human tumour (A549) and rodent (HTC, CHO) cells, grown in medium containing an inhibitor of the FAD-dependent polyamine oxidase (PAO). Inhibition of PAO has little effect on cell growth or on the cellular content of the major polyamines, putrescine, spermidine or spermine, found in proliferating cells in culture, but decreases cellular putrescine content in heat shocked cells. Putrescine and spermidine are generated when N1AcSpd or N1-acetylspermine (N1AcSpm) respectively is added to either human or rodent cells depleted of the former amines by alpha-difluoromethylornithine. N1AcSpm is formed in polyamine-depleted human A549 cells when N1AcSpd is added to cultures treated with the PAO inhibitor. This reaction does not occur in either rodent line, suggesting that N1AcSpd can be converted directly into N1AcSpm in human, but not rodent, cells under specific conditions. The data presented demonstrate that a variety of human and rodent cells express PAO activity and catabolize polyamines by a mechanism which includes PAO. PAO activity is of little consequence to proliferating A549, HTC or CHO cells in culture, but does produce new putrescine in both late-exponential-phase and heat-shocked cells. These findings suggest that polyamine catabolism is part of a general response of both rodent and human cells to a variety of environmental and physiological stresses.


Assuntos
Poliaminas/metabolismo , Espermidina/análogos & derivados , Espermina/análogos & derivados , Animais , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Eflornitina/farmacologia , Temperatura Alta , Humanos , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Putrescina/análogos & derivados , Putrescina/farmacologia , Ratos , Espermidina/metabolismo , Espermina/metabolismo , Células Tumorais Cultivadas , Poliamina Oxidase
7.
Int J Radiat Oncol Biol Phys ; 19(1): 89-96, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2116388

RESUMO

A Phase I clinical trial has been initiated at the University of Arizona Cancer Center which combines escalating oral doses of the polyamine biosynthesis inhibitor alpha-difluoromethylornithine (DFMO), with systemic hyperthermia (approximately 41.5 degrees C) in the treatment of metastatic melanoma. The rationale for the combination of hyperthermia and polyamine biosynthesis inhibitors in the treatment of human cancers includes studies which show that depletion of endogenous polyamines, as a result of treatment with DFMO, sensitizes both rodent and human tumor cells to the cytotoxic effects of hyperthermia. Heat shock induces the first enzyme in polyamine catabolism, spermidine/spermine N1-acetyltransferase (N1-SAT). The consequently acetylated forms of spermidine and spermine are then constitutively oxidized by the enzyme polyamine oxidase (PAO). Both CHO and human A549 lung cancer cells exhibit heat-inducible polyamine acetylation, display potent heat sensitization after polyamine depletion, and ultimately reveal prolonged expression of thermotolerance. Conversely, HeLa cells do not demonstrate heat-inducible polyamine catabolism, are not sensitized to heat with DFMO, and display more rapid kinetics of thermotolerance decay. These laboratory studies suggest that enhancement of the cytotoxic action of hyperthermia by DFMO occurs as a consequence of the inhibition of polyamine catabolism, a heat-inducible process that affords some form of protection to cells undergoing heat stress. Human melanoma cultures demonstrate heat-inducible polyamine catabolism and are sensitized to hyperthermic cytotoxicity by DFMO. To date, 24 systemic hyperthermia treatments have been delivered to nine patients with metastatic melanoma in conjunction with oral DFMO under this Phase I clinical trial.


Assuntos
Eflornitina/farmacologia , Hipertermia Induzida , Melanoma/terapia , Poliaminas/metabolismo , Acetilação , Animais , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada , Cricetinae , Cricetulus , Eflornitina/uso terapêutico , Glutationa/metabolismo , Células HeLa/efeitos dos fármacos , Temperatura Alta , Humanos , Cinética , Melanoma/tratamento farmacológico , Melanoma/secundário , Oxirredução , Choque , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
8.
Biochem J ; 267(3): 601-5, 1990 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-2111132

RESUMO

The enzyme spermidine/spermine N1-acetyltransferase (N1-SAT) is rapidly induced by heat shock in CHO and A549 cells, with activity declining by 24 h. Depletion of intracellular polyamines by alpha-difluoromethylornithine, an inhibitor of ornithine decarboxylase, blocks this induction. Re-addition of putrescine to these cultures restores the response to heat shock, with a concomitant increase in intracellular N1-acetylspermidine. Diaminopropane is more than twice as effective as the naturally occurring diamine putrescine, suggesting that the propylamine moiety of spermidine is involved in the regulation of N1-SAT induction. Inhibitor studies indicate transcriptional activation and that the enzyme has an apparent half-life of 30-60 min. A second heat shock rapidly inhibits induced N1-SAT activity, which decays with a half-life of 2-3 min. Despite its induction by heat, N1-SAT is not a stable enzyme, suggesting that the activity observed is not due to a modification of an existing peptide, but is due to a transcriptional event, which may justify the inclusion of this enzyme in the family of heat-shock proteins.


Assuntos
Acetiltransferases/biossíntese , Aminas Biogênicas/fisiologia , Temperatura Alta , Acetiltransferases/análise , Animais , Células Cultivadas , Cricetinae , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Diaminas/farmacologia , Eflornitina/farmacologia , Indução Enzimática , Humanos , Putrescina/farmacologia , Transcrição Gênica
9.
Biochem J ; 260(2): 487-90, 1989 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2548479

RESUMO

In exponential-phase Chinese-hamster cells, 0.1 mM-diethyldithiocarbamate (DDC) afforded greater than 1 log survival protection to cultures treated before and during exposure to 1 mM-H2O2. Both DDC and H2O2 treatment stimulated the activity of ornithine decarboxylase (ODC), the first enzyme in polyamine synthesis, within 4 h of exposure. DDC, and to a lesser degree H2O2, also stimulated the activity of spermidine N1-acetyltransferase (SAT), the rate-limiting enzyme in polyamine catabolism. The increase in SAT activity, after exposure to DDC or another stress (heat shock), was inhibited in cells depleted of putrescine and spermidine by alpha-difluoromethylornithine (DFMO), the enzyme-activated suicide inhibitor of ODC. Pretreatment with DFMO or heat shock also induced resistance to H2O2 cytotoxicity. Since SAT activity is low in resting cells, yet stimulation of enzyme activity depends on endogenous spermidine pools, these results suggest that the expression of SAT activity occurs by a mechanism involving a stress-dependent displacement of spermidine into a new intracellular compartment. The stimulation of ODC and SAT activities does not appear to be a necessary component of the mechanism by which DDC protects cells from H2O2 cytotoxicity, although spermidine displacement may be a common facet of the cellular response to stress.


Assuntos
Ditiocarb/farmacologia , Peróxido de Hidrogênio/farmacologia , Poliaminas/metabolismo , Acetiltransferases/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cricetinae , Cricetulus , Eflornitina , Feminino , Temperatura Alta , Ornitina Descarboxilase/metabolismo , Ovário/efeitos dos fármacos , Ovário/metabolismo
10.
Int J Radiat Oncol Biol Phys ; 16(2): 451-7, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2921147

RESUMO

Heat shock stimulates both exogenous and endogenous polyamine oxidation in mammalian cells, but by distinct biochemical mechanisms. Exogenously added polyamines are oxidized in serum via the temperature-dependent activation of a single class of enzymes, the copper-dependent amine oxidases. Endogenous polyamines undergo a two-step reaction sequence involving acetylation by a heat-inducible acetyltransferase and subsequent oxidation by a constitutively expressed, flavin-dependent polyamine oxidase. In both instances, polyamine oxidation generates hydrogen peroxide and reactive aldehydes which influence cell viability as demonstrated by inhibitor studies. Aminoguanidine, an inhibitor of the copper-dependent amine oxidases, confers protection to cells during either a severe 43 degrees C heat shock or a relatively nontoxic heat stress followed by incubation at 37 degrees C, all in the presence of exogenous spermidine. Specific inhibition of the endogenous polyamine oxidase will also confer partial survival protection after heat shock, but only in cultures that have been previously depleted of cellular glutathione. These data confirm that hyperthermic stress can generate an oxidative stress in mammalian cells via induction of polyamine oxidation. Further, through distinct extracellular and intracellular mechanisms, these temperature-dependent polyamine oxidation reactions can modulate cell viability.


Assuntos
Amina Oxidase (contendo Cobre) , Temperatura Alta , Poliaminas/metabolismo , Acetiltransferases/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Poliaminas/administração & dosagem , Estresse Fisiológico/enzimologia , Poliamina Oxidase
11.
Transplantation ; 46(1): 61-5, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2839915

RESUMO

Interstitial pneumonitis (IP) occurred in 20 of 143 (14%) patients who received cytoreductive therapy followed by autologous bone marrow transplantation (BMT) as treatment for malignancy. IP occurred at a median onset time of 41 days (5 to 624 days). All but three of the episodes were fatal. Of the thirteen cases in which tissue was examined, half were idiopathic; the remainder were due to various infectious agents. The actuarial incidences of idiopathic (7%) and CMV IP (2%) in these marrow autograft recipients were lower than the incidences of idiopathic (19%) and CMV IP (17%) in comparably treated recipients of allogeneic BMT (P less than or equal to 0.001 for both comparisons).


Assuntos
Transplante de Medula Óssea , Leucemia/terapia , Linfoma/terapia , Fibrose Pulmonar/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Infecções por Citomegalovirus/complicações , Feminino , Humanos , Masculino , Fatores de Risco , Viroses/complicações
12.
Blood ; 71(5): 1432-7, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-2833959

RESUMO

Cytomegalovirus (CMV) infection was detected in 65 of 143 (45%) autologous bone marrow transplant (BMT) patients. CMV pneumonitis occurred in only 2% of the patients and CMV retinitis occurred in none. Infection occurred in half of the 40 initially seronegative patients and 47% of the 94 initially seropositive patients. Among initially seropositive patients, platelet recovery was slower in infected patients than in those not infected (97 v 35 days median, P = .003), and neutrophil recovery was slightly delayed in infected patients (31 days v 24 days, P = .02). Although the incidence of CMV infection was comparable in autologous and allogeneic BMT patients, CMV pneumonitis was less frequent in autologous BMT patients (2% v 12%, P less than .001). The risk for CMV pneumonitis in autologous BMT patients was comparable with that in allogeneic BMT patients without graft-v-host disease (GVHD) (2% v 6%), but significantly lower than the risk in allogeneic BMT patients with GVHD (2% v 23%, P less than .001).


Assuntos
Transplante de Medula Óssea , Infecções por Citomegalovirus/etiologia , Complicações Pós-Operatórias/epidemiologia , Infecções por Citomegalovirus/epidemiologia , Doença Enxerto-Hospedeiro , Humanos , Contagem de Leucócitos , Maryland , Contagem de Plaquetas , Pneumonia Viral/epidemiologia , Pneumonia Viral/etiologia , Retinite/epidemiologia , Retinite/etiologia , Transplante Autólogo , Transplante Homólogo , Ativação Viral
13.
Bone Marrow Transplant ; 2(1): 7-14, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3332159

RESUMO

Twenty patients with poor prognosis non-Hodgkin's lymphoma received regimens which employed cyclophosphamide and total body irradiation followed by autologous bone marrow rescue. There were two toxic deaths. All 10 patients with residual disease prior to treatment achieved a complete remission. Ten patients survive disease free from 1.4 to 9.5 years and median survival exceeds 2.9 years. The actuarial 3-year disease-free survival is 50%. Treatment with cyclophosphamide and total body irradiation followed by autologous bone marrow infusion is an effective salvage regimen for poor prognosis lymphoma. Durable long-term remissions can be achieved.


Assuntos
Transplante de Medula Óssea , Ciclofosfamida/uso terapêutico , Linfoma não Hodgkin/terapia , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Prognóstico , Irradiação Corporal Total
14.
Int J Hyperthermia ; 3(3): 187-98, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3116124

RESUMO

Thirteen dogs were entered into a pilot study to assess the toxicities associated with polyamine biosynthetic enzyme inhibitors as heat sensitizing drugs and whole body hyperthermia either alone or in combination. Disease-free and tumour-bearing animals were entered in an effort to assess the response of canine lymphoproliferative disorders as well. Conclusions reached were as follows. (1) A large tumour burden precludes treatment. (2) Liver involvement and decreased platelet numbers would appear to offer a grave prognosis for survival and should be assessed closely in determining eligibility. (3) Polyamine biosynthetic enzyme inhibitors and whole body hyperthermia appear to be tumoricidal alone or in combination, although less effective and with greater toxicities than accepted chemotherapeutic regimens. (4) Heat sensitization in vivo has not yet been demonstrated.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hipertermia Induzida , Transtornos Linfoproliferativos/terapia , Radiossensibilizantes/uso terapêutico , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Terapia Combinada , Cães , Eflornitina/sangue , Eflornitina/uso terapêutico , Temperatura Alta , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/enzimologia , Mitoguazona/uso terapêutico , Projetos Piloto , Contagem de Plaquetas
15.
Cancer Res ; 47(3): 816-20, 1987 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-3100026

RESUMO

When exposed to alpha-difluoromethylornithine (DFMO), an inhibitor of polyamine biosynthesis, Chinese hamster ovary cells become increasingly sensitive to the cytotoxic effects of elevated temperatures (D.J.M. Fuller and E.W. Gerner, Cancer Res., 42:5046-5049, 1982). This sensitization becomes marked at times greater than 24 h after drug removal, and by 48 h, polyamine-depleted cells that have been exposed to 43 degrees C for 90 min have clonogenic survival values more than two orders of magnitude lower than control populations. Dose response studies demonstrate that, when measured 36 h after removal of the drug, hyperthermic cytotoxicity is maximally potentiated by exposure to DFMO for times as short as 2 to 4 h. A drug concentration of 1 mM for 8 h also elicits maximal response. An additional 8-h drug treatment 24 h after the first fails to further reduce survival in response to heat shock, suggesting the effects of the first exposure are persistent. Intracellular putrescine pools are depleted by the drug within 8 h, and spermidine levels continue to decline for up to 50 h. Consistent with these observations, ornithine decarboxylase (EC 4.1.1.17) activity is found to be reduced for up to 48 h after drug removal. The concomitant depression of spermidine is reflected in the elevation of S-adenosylmethionine decarboxylase (EC 4.1.1.50), which is substrate limited. Putrescine and spermidine show no sign of reaccumulation until approximately 4 days after DFMO exposure. Exposure to exogenous putrescine reversed the sensitization to heat shock induced by DFMO. This effect is quite specific for putrescine (1.4-diaminobutane) and is not replicated by other diamine homologues ranging from 1.3-diaminopropane to 1.8-diaminooctane. Polyamine-depleted cells express thermotolerance with kinetics similar to control cells although overall survival levels are lower. These results suggest that the mechanism of induction and expression of thermotolerance is independent of the role of acid-soluble polyamine pools in cellular responses to heat shock.


Assuntos
Sobrevivência Celular , Eflornitina/toxicidade , Temperatura Alta , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Cricetinae , Cricetulus , Feminino , Cinética , Ovário , Putrescina/metabolismo , Espermidina/metabolismo , Espermina/metabolismo
16.
J Prosthet Dent ; 57(2): 236-43, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3470515

RESUMO

This study investigated the relationship between the tooth contact sound and its wave pattern, and the interrelationships of the components of the wave pattern. The hypothesis that the tooth contact sound and features of its wave pattern are analogues of the quality of occlusion was also investigated. The sample consisted of 133 subjects. By means of a standardized technique, tooth contact sounds produced during habitual closure were recorded and used to produce wave patterns. Statistical tests were used to determine whether significant relationships existed between selected gnathosonic parameters and aspects of the quality of occlusion that had been assessed by clinical examination. The findings of this study lead to the following conclusions: The measures of wave pattern duration (ALPHDUR and TOTDUR) are significantly related to the amplitude of the wave pattern (or the loudness of the tooth contact sound). Thus, allowance should be made for variations in amplitude when considering the relationship between measures of wave pattern duration and other factors. The measurement of ALPHDUR is independent of the recording equipment used to produce the wave pattern. ALPHDUR may therefore be of use in the comparison of gnathosonic data that have been produced by different recording techniques. ALPHDUR is the wave pattern component that bears the strongest relationship to the categorized tooth contact sound. In some respects, three gnathosonic parameters (tooth contact sound category, ALPHDUR [ADJ], AND AMPL) might be considered to be analogous of the quality of occlusion. Of these, the subjectively assessed tooth contact sound would appear to have some practical application in routine dental practice.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Oclusão Dentária , Som , Dente/fisiologia , Adulto , Oclusão Dentária Central , Feminino , Humanos , Masculino
17.
J Cell Physiol ; 127(1): 114-20, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3958058

RESUMO

Chinese hamster cells (line CHO) maintained in McCoy's 5A medium (modified) supplemented with insulin (10 micrograms/ml), transferrin (5 micrograms/ml), and ferrous sulfate (1.1 microgram/ml) proliferate at rates similar to cultures growing in the McCoy's medium supplemented with 10% fetal bovine serum. Colony-forming ability is similar in cultures supplemented with either serum or the combination of growth factors. By 6 hours after replacement of serum with growth factors, ornithine decarboxylase (ODCase) activity increases, reaching a maximum value by 24 hours after serum replacement. This maximum is cell density dependent and can exceed a 30-fold increase over enzyme activity in cultures supplemented with serum. The increased enzyme activity is due to a decrease in the turnover rate of the enzyme, based on protein synthesis inhibition studies, and an accumulation of active enzyme molecules rather than an activation of existing molecules, since the catalytic activity of ODCase, determined using the radiolabeled form of alpha-difluoromethylornithine (an enzyme-activated, irreversible inhibitor of ODCase) in concert with supplements. Intracellular putrescine and spermidine levels are substantially decreased when cultures are maintained in medium supplemented with insulin, transferrin, and ferrous sulfate, rather than serum, which is the sole source of exogenous ornithine. Titration of cultures growing in the defined medium with ornithine leads to a decrease in ODCase activity and an increase in intracellular putrescine and spermidine levels. Putrescine- and spermidine-dependent S-adenosyl-L-methionine decarboxylase activities are similar in cultures maintained in either medium. These data demonstrate that some, but not all, aspects of polyamine biosynthesis are affected by the availability of ornithine, the first substrate in the pathway.


Assuntos
Ornitina Descarboxilase/metabolismo , Poliaminas/metabolismo , Adenosilmetionina Descarboxilase/metabolismo , Animais , Sangue , Contagem de Células , Divisão Celular , Linhagem Celular , Cricetinae , Meios de Cultura , Feminino , Ornitina/metabolismo , Ornitina/farmacologia , Ovário , Putrescina/metabolismo , Espermidina/metabolismo , Espermina/metabolismo
18.
J Cell Physiol ; 125(3): 567-72, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3840806

RESUMO

When monolayer Chinese hamster cells are treated with trypsin for short periods of time, ornithine decarboxylase (ODCase) activity increases two- to fourfold. This increase can be blocked by aprotinin, a protease inhibitor, and is not observed when cultures are dislodged from substrate mechanically prior to contact with exogenous trypsin. The trypsin-induced increase in ornithine decarboxylase activity is not due to degradation of enzyme or inhibitor molecules or to new enzyme synthesis. Immunoprecipitable protein, radiolabeled with [3H]alpha-difluoromethylornithine in vitro, is the same molecular weight in cells harvested with or without trypsin. Protein-bound levels of this specific enzyme-activated irreversible inhibitor of ornithine decarboxylase are unchanged by trypsin treatments that increase enzyme activity. Trypsin treatment of rat embryonic fibroblasts, transformed by a temperature-sensitive mutant of Rous sarcoma virus, increases ODCase activity in cells growing at the nonpermissive, but not at the permissive, temperature for the transformed phenotype. These results suggest that ornithine decarboxylase can be activated by exogenous trypsin treatment in a manner that is dependent on cell adhesion properties, which are modified in transformed cells.


Assuntos
Ativação Enzimática/efeitos dos fármacos , Ornitina Descarboxilase/metabolismo , Tripsina/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Cricetinae , Cricetulus , Feminino , Fibroblastos/enzimologia , Inibidores da Ornitina Descarboxilase , Ovário , Biossíntese de Proteínas , Ratos , Temperatura
19.
Blood ; 65(6): 1504-10, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3888315

RESUMO

This phase I study was conducted to determine the maximal safe concentration of 4-hydroperoxycyclophosphamide (4HC) that could be used for in vitro treatment of bone marrow from patients with acute leukemia undergoing autologous bone marrow transplantation. Concentrations of 40 to 120 micrograms/mL of 4HC were used in 30 patients with relapsed or high-risk acute leukemia and in six patients with nonleukemic malignancies. All patients received marrow-lethal cytoreductive therapy followed by infusion of the 4HC-treated marrow. Complete inhibition of granulocyte and macrophage colony-forming cells was obtained at 80 micrograms/mL. Nevertheless, only one transplant-related death and otherwise full hematologic recovery was observed at concentrations of 4HC up to 100 micrograms/mL. At 120 micrograms/mL, there were three transplant-related deaths, including two of the three patients who required the infusion of reserve marrow. Among the acute leukemia patients, three remain in complete remission at 1,337, 1,017, and 967 days after transplant. Among the nonleukemic patients, two remain in complete remission at 1,081 and 1,017 days after transplant. At the maximum safe concentration of 4HC (100 micrograms/mL), satisfactory hematologic recovery can be obtained, despite elimination of detectable hematopoietic progenitors.


Assuntos
Transplante de Medula Óssea , Medula Óssea/efeitos dos fármacos , Ciclofosfamida/análogos & derivados , Leucemia/terapia , Doença Aguda , Adolescente , Adulto , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Ciclofosfamida/efeitos adversos , Ciclofosfamida/farmacologia , Feminino , Humanos , Técnicas In Vitro , Leucopenia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Transplante Autólogo
20.
Radiat Res ; 95(1): 124-9, 1983 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6308707

RESUMO

The polyamines putrescine, spermidine, and spermine have been shown to sensitize Chinese hamster ovary (CHO) cells to the cytotoxic effects of elevated temperatures. This sensitization occurs in the order spermine greater than spermidine greater than putrescine. A series of homologs of the diamine putrescine demonstrated little variance in the degree of potentiation until a chain length equivalent to that of spermidine was employed (1,8-diaminooctane). Two compounds bearing structural similarities to spermidine gave rather different results when combined with heat. Methylglyoxal bis(guanylhydrazone) (MGBG), an antiproliferative drug, sensitized cells to heat, while S-2-(3-aminopropylamino)-ethyl phosphoric acid (WR-2721), a radioprotector, had no measureable effect on 43 degrees C-induced cytotoxicity. Together, these results point out the primary importance of two terminal amino groups separated by either carbon, or carbon and nitrogen, atoms in an aliphatic chain in the observed sensitization of heat-induced cytotoxicity by polyamines. These data suggest specific dimensional characteristics of the presumed negatively charged structure(s) with which the polyamines are interacting to elicit this effect.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Temperatura Alta , Poliaminas/farmacologia , Amifostina/farmacologia , Animais , Cadaverina/farmacologia , Linhagem Celular , Cricetinae , Cricetulus , Diaminas/farmacologia , Relação Dose-Resposta a Droga , Mitoguazona/farmacologia , Putrescina/farmacologia , Espermidina/farmacologia
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