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1.
Am J Biol Anthropol ; 182(3): 428-439, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37560788

RESUMO

OBJECTIVES: The Levantine Middle Bronze Age (MBA, circa 2000-1500 BCE) marks a period of increased trade and regional interaction, spurred on by technological developments. In light of previous research exhibiting limited mobility in Sidon, further investigation was conducted using biodistance analysis to understand local population history and site development. MATERIALS AND METHODS: Dental nonmetric traits, a proxy for genetic information, were explored using ASUDAS on a sub-sample of primary inhumations (n = 35). The biodistance matrix was generated using Gower distance measures, and further tested using PERMDISP, PERMANOVA, Mantel test and hierarchical cluster analysis. The data was also contrasted to 87 Sr/86 Sr and δ18 O as well as δ13 C and δ15 N values. RESULTS: There were no significant diachronic differences in isotopes values, and there was biological continuity (n = 35, Mantel test r = 0.11, p = 0.02, comparing local phases and biodistance). The analysis also suggested of a sub-group of individuals with biological proximity shared a more limited range of mobility and dietary habits. CONCLUSIONS: The isotopes (87 Sr/86 Sr, δ18 O, δ13 C, δ15 N) and biodistance analysis conducted on the Sidon College site skeletal assemblage exhibits stability and continuity of the people, despite the site's increasing role in the maritime network. This continuity may have been a key factor in Sidon's success, allowing it to accumulate wealth and resources for centuries to come.

2.
Mol Inform ; 33(3): 171-82, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27485687

RESUMO

A comprehensive data-set from a multidisciplinary feeding experiment with the probiotic Enterococcus faecium was analyzed to elucidate effects of the probiotic on growing piglets. Sixty-two piglets were randomly assigned to a control (no probiotic treatment) and a treatment group (E. faecium supplementation). Piglets were weaned at 26 d. Age-matched piglets were sacrificed for the collection of tissue samples at 12, 26, 34 and 54 d. In addition to zootechnical data, the composition and activity of intestinal microbiota, immune cell types, and intestinal responses were determined. Our systems analysis revealed clear effects on several measured variables in 26 and 34 days old animals, while response patterns varied between piglets from different age groups. Correlation analyses identified reduced associations between intestinal microbial communities and immune system reactions in the probiotic group. In conclusion, the developed model is useful for comparative analyses to unravel systems effects of dietary components and their time resolution. The model identified that effects of E. faecium supplementation most prominently affected the interplay between intestinal microbiota and the intestinal immune system. These effects, as well as effects in other subsystems, clustered around weaning, which is the age where piglets are most prone to diarrhea.

3.
Bone Marrow Transplant ; 48(1): 85-93, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22732699

RESUMO

We evaluated immune reconstitution in 58 adults who received hematopoietic SCTs from allogeneic siblings (allosib), matched unrelated donors (MUD) or cord blood (CB) at 90-day intervals for 1 year post transplant. CB recipients had a higher incidence of infections in the first 100 days compared with allosib and MUD recipients. The number of circulating T cells was lower in CB recipients compared with MUD recipients at 90 days and compared with allosib recipients at 180 days. Spectratype analysis of the TCR Vß complementarity determining region 3 (CDR3) of patient lymphocytes revealed that the TCR repertoire remained poorly diversified even at 360 days in nearly all patients. In contrast, the number of circulating B cells was significantly elevated in CB recipients compared with allosib recipients throughout the first year post transplant and compared with MUD recipients at 9-12 months. Spectratype analysis of the B-cell receptor V(H) CDR3 showed that the B-cell repertoire was diversified in most patients by 90 days. CD5(pos) B cells from assayed CB recipients expressed intracellular IL-10 early post transplant. Our data suggest that B cells, in addition to T cells, may have a role in impaired immune responses in CB transplant patients.


Assuntos
Linfócitos B/imunologia , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Doença Enxerto-Hospedeiro/imunologia , Hospedeiro Imunocomprometido , Infecções Oportunistas/imunologia , Adulto , Idoso , Linfócitos B/metabolismo , Antígenos CD5/sangue , Antígenos CD5/genética , Antígenos CD5/metabolismo , Regiões Determinantes de Complementaridade/sangue , Regiões Determinantes de Complementaridade/química , Regiões Determinantes de Complementaridade/genética , Regiões Determinantes de Complementaridade/metabolismo , Feminino , Doença Enxerto-Hospedeiro/sangue , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/metabolismo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Illinois/epidemiologia , Incidência , Interleucina-10/metabolismo , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/sangue , Infecções Oportunistas/epidemiologia , Infecções Oportunistas/metabolismo , Receptores de Antígenos de Linfócitos B/sangue , Receptores de Antígenos de Linfócitos B/química , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/metabolismo , Receptores de Antígenos de Linfócitos T/sangue , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Irmãos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transplante Homólogo
4.
Bone Marrow Transplant ; 37(5): 479-84, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16435021

RESUMO

Patients referred for hematopoietic stem cell transplantation (HSCT) often have knowledge deficits about their disease and overestimate their prognosis making it difficult initially to discuss potentially life-threatening transplant options. To determine patients' understanding of their disease and the adequacy of a 3-h consultation at our center, we developed a survey that measured perceived knowledge deficits of disease, prognosis, and emotional status before and after their initial consultation. Ninety nine consecutive eligible patients completed the survey. Although 76.7% claimed adequate information about their disease pre-HCST visit, 51.5 and 41.4% respectively lacked knowledge about their 1-year prognosis with and without any therapy. After the visit, 66.7% of the patients had obtained enough information to make an informed decision regarding HSCT versus 23.2% pre-visit, and a significant reduction in the need for further information was reported by 53.5% of patients (P<0.001). Patients were not overwhelmed or confused by the visit and there was a small but significant decrease in negative affect. Measures to increase patients understanding of their disease and its prognosis pre-HSCT consultation visit are warranted; however, a 3-h consultation visit provides the majority of patients with sufficient information to make an informed decision about the risk/benefit ratio of HSCT.


Assuntos
Doenças Hematológicas , Transplante de Células-Tronco Hematopoéticas , Educação de Pacientes como Assunto/normas , Encaminhamento e Consulta/normas , Coleta de Dados , Tomada de Decisões , Nível de Saúde , Humanos , Consentimento Livre e Esclarecido/normas , Prognóstico , Medição de Risco
5.
Polim Med ; 18(1-2): 51-65, 1988.
Artigo em Polonês | MEDLINE | ID: mdl-2975375

RESUMO

The physico mechanical properties of films, vascular prostheses and nets made of polyethylene terephthalate and polyethylene film treated with the low temperature plasma were investigated. The plasma was generated by glow discharge in air under the following conditions: gas pressure - , current - 0.4-0.6 A, time of treatment - 40-240 s. stated that the angles of wetting with water and collagen solution of films treated with plasma decreases considerably. Sharp decreasing of wetting angles is followed by quick rise of the between water and polymeric film, and also by the increasing of free surface energy. The increasing of the wettability does not change during the storing time. The breaking stress and extension of the films treated with plasma are the same or a little bit higher than those of the untreated ones. The collagen modified by radiation shows high adhesion to the polymeric materials treated with plasma. The value of this adhesion 6 x 10(5) mN/m for polyester film, is about 6 times higher than the value of adhesion obtained by other authors, if the polyester film was treated with air plasma generated by spark discharge method.


Assuntos
Colágeno/farmacologia , Polietilenotereftalatos/síntese química , Polietilenos/síntese química , Próteses e Implantes , Adesividade , Ar , Temperatura Baixa , Tecnologia , Resistência à Tração , Viscosidade
6.
Cancer Chemother Pharmacol ; 21(2): 122-8, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2832091

RESUMO

A phase I and pharmacokinetic study of a novel lipid-soluble antifolate, 2,4 diamino-5-adamantyl-6-methyl pyrimidine ethane sulfonate (DAMP-ES) has been carried out on two schedules: I--daily x5; II--24-h continuous infusion. In schedule I, doses of 10-90 mg/m2 per day were evaluated. Dose-limiting toxicity was hematologic, but nausea and vomiting, skin rash, diarrhea, anorexia, alopecia, mucositis, and neurotoxicity were also noted. In schedule II, doses of 192 and 240 mg/m2 were evaluated. Dose-limiting toxicity was neurotoxicity, but hematologic toxicity was also marked. Recommended starting doses for phase II studies are 75 mg/m2 per day for 5 days or 192 mg/m2 by continuous infusion for 24 h. Pharmacokinetic studies indicated a beta-phase plasma half-life of 12.4-24 h and a large and variable volume of distribution.


Assuntos
Antagonistas do Ácido Fólico/farmacocinética , Neoplasias/metabolismo , Adamantano/análogos & derivados , Adamantano/farmacocinética , Idoso , Alcanossulfonatos/farmacocinética , Fenômenos Químicos , Química , Avaliação de Medicamentos , Feminino , Antagonistas do Ácido Fólico/administração & dosagem , Antagonistas do Ácido Fólico/efeitos adversos , Antagonistas do Ácido Fólico/uso terapêutico , Humanos , Infusões Intravenosas , Masculino , Matemática , Microcomputadores , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Software
7.
NCI Monogr ; (5): 165-70, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2448653

RESUMO

In vitro and in vivo studies have been carried out in mouse and human tumors to investigate the biochemical and pharmacologic basis for the selectivity of 5-fluorouracil (FUra) action. Combination chemotherapy with FUra and thymidine was performed to determine the therapeutic relevance of 5-fluorouridine triphosphate (FUTP) incorporation into RNA. The results of these studies indicate that modulation of FUra cytotoxicity by deoxythymidine (dThd) did occur but failed to produce any significant therapeutic advantages in patients with advanced colorectal cancer. Modulation of FUra bioactivation via the deoxyribonucleotide pathway by coadministration of high-dose folinic acid resulted in enhanced therapeutic response rate of gastrointestinal tumor patients. This manuscript summarizes the preclinical and clinical findings on the metabolic modulation of FUra activity by dThd and folinic acid.


Assuntos
Fluoruracila/administração & dosagem , Leucovorina/administração & dosagem , Animais , Biotransformação , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , DNA/metabolismo , Sinergismo Farmacológico , Fluoruracila/farmacologia , Ácido Fólico/metabolismo , Humanos , Leucovorina/farmacologia , Leucemia L1210/metabolismo , Camundongos , RNA/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Timidina/metabolismo , Timidilato Sintase/metabolismo
8.
J Clin Oncol ; 4(10): 1510-7, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3489819

RESUMO

Many patients with gastrointestinal (GI) tumors develop extensive peritoneal and serosal metastasis and/or malignant ascites which respond poorly to available treatments. Twelve patients with tumors confined primarily to the intraabdominal cavity were treated with intraperitoneal (IP) 5-fluorouracil (5-FU) in escalating concentrations (2 to 4 mmol/L) in combination with leucovorin (dl-5-formyltetrahydrofolic acid or folinic acid; dl-CF) in a 2-L volume, either by eight consecutive four-hour dwells or once daily for five days. CF dose was 20.8 or 104 mumol/L. Nine of the patients had pancreatic carcinoma, one had stomach carcinoma, and two had hepatobiliary neoplasms. Median age was 62.5 years and median Eastern Cooperative Oncology Group (ECOG) performance status was 3. Toxicity included mucositis, diarrhea, nausea and vomiting, leucopenia, skin rash, and abdominal pain, and was similar to that previously reported for IP 5-FU used as a single agent. Four episodes of peritonitis occurred, but all patients responded to antibiotics. At the 20.8 mumol/L dose, dl-CF concentration in the peritoneal fluid declined from 10.4 +/- 3.0 3.0 mumol/L at one hour to 4.9 +/- 2.2 mumol/L at four hours, corresponding to a mean absorption half-life of 127 +/- 49 minutes and a mean peritoneal clearance of 13.0 +/- 4.5 mL/min. Decline was biphasic in all but five of the 19 exchanges evaluated. The levels of l-CF (biologically active isomer of dl-CF) were 2.8 +/- 2.5 mumol/L after 60 minutes and 1.2 +/- 0.7 mumol/L after four hours. The peritoneal area under the concentration v time curve (AUC) for 5-FU increased proportionally with dose. For example, the AUC at 2.0 and 3.5 mmol/L was 129 +/- 25 and 201 +/- 23 mmol/L X minute, respectively. However, the maximal peritoneal to plasma AUC ratio was 461 at the 2 mmol/L dose, but decreased with increasing doses as systemic clearance decreased. This regimen was well tolerated in patients with advanced cancer, but must be evaluated further to determine its clinical efficacy.


Assuntos
Neoplasias Abdominais/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/metabolismo , Cateterismo/efeitos adversos , Avaliação de Medicamentos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/metabolismo , Humanos , Injeções Intraperitoneais , Cinética , Leucovorina/administração & dosagem , Leucovorina/metabolismo , Masculino , Pessoa de Meia-Idade , Peritônio/metabolismo , Peritonite/etiologia
9.
Cancer Biochem Biophys ; 7(1): 27-38, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6667452

RESUMO

Geometry-optimized CNDO/2 molecular orbital calculations were carried out on 2, 4-diamino-5-(1-adamantyl 1)-6-methyl pyrimidine (DAMP), a potent inhibitor of mammalian dihydrofolate reductase which is now in clinical trials, and on its inactive 5-(1-naphthyl) analogue (DNMP-1). Crystallographic data show that DAMP (as the ethylsulfonate salt) has a severely distorted, N1 protonated, pyrimidine ring and has steric crowding of the 6-methyl and adamantyl hydrogens whereas DNMP-2 (as a methanol complex) has a planar, nonprotonated pyrimidine ring that is nearly perpendicular to the naphthalene ring. The CNDO/2 results largely reproduce the crystal structure geometry and show that the ring distortions in DAMP are initiated by steric conflicts between the adamantyl group and the 4- and 6-substituents on the ring. In DNMP-1, the non-interfering naphthyl ring induces little strain within the pyrimidine ring and the effect of protonation is negligible. Rotation about the bond joining the two ring groups is restricted in DAMP by a broad barrier of ca. 8.0 kcal mol-1, and no conformation was successful in relieving steric conflicts and hence reducing the ring distortions. In DNMP-1, rotation is less hindered overall with a broad region of accessible conformational space and a maximum barrier of ca. 7.2 kcal mol-1 for the coplanar conformation. The electronic charge distributions of DAMP and DNMP-1 are almost identical and protonation is preferred at N1 rather than at N3 by ca. 3.7 kcal mol-1 for both DAMP and DNMP-1. The calculations establish that the present methodology can be useful as a predictive tool with regard to the structure and conformational characteristics of these and related species.


Assuntos
Adamantano/análogos & derivados , Antagonistas do Ácido Fólico , Modelos Moleculares , Cristalografia , Raios X
11.
Hum Genet ; 64(1): 55-7, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6409800

RESUMO

Hybrids were performed between cell lines derived from four patients with Fanconi's anemia in which different biochemical lesions have been postulated. Complementation studies in these hybrids based on the rate of mitomycin C-induced chromosomal damage supported the concept of allelic mutations. It was therefore concluded that intergenic heterogeneity plays a much lower role in Fanconi's anemia than in Xeroderma pigmentosum or Ataxia teleangiectasia, two other disorders with defective DNA repair.


Assuntos
Anemia Aplástica/genética , Reparo do DNA , Anemia de Fanconi/genética , Teste de Complementação Genética , Linhagem Celular , Células Cultivadas , Aberrações Cromossômicas , Humanos , Células Híbridas/efeitos dos fármacos , Células Híbridas/ultraestrutura , Técnicas In Vitro , Mitomicina , Mitomicinas/farmacologia
12.
Cancer Res ; 42(11): 4824-6, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6982097

RESUMO

A total of 15 patients with advanced neoplastic disease, 13 with different solid tumors, one with lymphoma, and one with acute lymphocytic leukemia, underwent treatment consisting of continuous infusion of methotrexate (2 g/sq m/day) with concomitant thymidine (8 g/sq m/day) and leucovorin (1 mg/sq m/day). The dose of methotrexate was increased progressively by lengthening the methotrexate infusion from 2 to 7 days. After cessation of methotrexate infusion, thymidine and leucovorin were continued until the plasma level of methotrexate decreased to 2 X 10(-8) M. Toxicity was mucositis (23 of 27 evaluable courses), leukopenia (15 of 26 evaluable courses), thrombocytopenia (10 of 26 evaluable courses), renal and hepatic toxicity and diarrhea. Plateau levels of plasma methotrexate or methotrexate plasma half-life did not correlate with toxicity.


Assuntos
Leucovorina/uso terapêutico , Metotrexato/uso terapêutico , Neoplasias/tratamento farmacológico , Timidina/uso terapêutico , Adulto , Idoso , Avaliação de Medicamentos , Feminino , Humanos , Cinética , Masculino , Metotrexato/sangue , Metotrexato/toxicidade , Pessoa de Meia-Idade
13.
Cancer Res ; 42(6): 2177-83, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7074598

RESUMO

The toxicology of a potentially useful antitumor agent, 2,4-diamino-5-adamantyl-6-methylpyrimidine (DAMP), and its ethanesulfonate salt has been studied in beagle dogs after 1 to 20 doses. Two types of toxicity could be discerned: the acute central nervous system toxicity manifested by vomiting, convulsions, and minor hypothermia; and the antiproliferative toxicity, similar to that of other folate antagonists, manifested by diarrhea, anorexia, loss of body weight, and hematological changes as well as changes in blood chemistry. There is evidence of a cumulative effect of the drug with respect to antiproliferative toxicity. Characteristically, the animals could be protected against the antiproliferative toxicity by simultaneous administration of folinic acid. The pharmacokinetics of the ethanesulfonate salt of DAMP was studied after i.v. administration of sublethal doses (5 mg/kg) of tritium-labeled drug. Sixty-three % of the administered dose was excreted in the urine and 10% was excreted in the feces within 48 hr after drug administration. Thus, about 27% of the drug was not recovered, and it is possible that it persists in the tissues for a period of several days. Analysis of the plasma and urine revealed that DAMP was metabolized rapidly. At least 2 metabolites were found in plasma and urine, one lipophilic and one hydrophilic, the latter being the predominant form. Pharmacokinetic data were successfully fitted to a model consisting of central and peripheral DAMP compartments and a DAMP metabolite compartment. DAMP was very rapidly sequestered in the peripheral compartment with a rapid phase half-life of 23 sec. The slower phase of DAMP plasma disappearance had a half-life of 3 hr. The short plasma half-life and rapid metabolism distinguished this drug from other lipophilic antifolates.


Assuntos
Adamantano/análogos & derivados , Antineoplásicos/toxicidade , Adamantano/metabolismo , Adamantano/toxicidade , Animais , Biotransformação , Cães , Eritrócitos/metabolismo , Fezes/análise , Feminino , Cinética , Masculino
14.
J Med Chem ; 25(4): 427-30, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7069721

RESUMO

2,4-Diamino-5-(1-adamantyl)-6-methylpyrimidine (DAMP) and its ethanesulfonate salt (DAMP-ES) are potent inhibitors of mammalian dihydrofolate reductase and also inhibit the growth of cultured cells as effectively as the drug methotrexate (MTX). DAMP is currently in phase I clinical studies. An analogue of DAMP having 5-(1-naphthyl) in place of the adamantyl group (DNMP) possesses little cytotoxic as well as enzyme inhibitory activity. The crystal and molecular structures of DAMPM-ES and DNMP were determined in order to elucidate the conformational aspects of drug specificity. The molecular conformation of DAMP-ES shows that the C8--C7 bond of the adamantyl ring is nearly coplanar with the pyrimidine ring (C8--C7--C5--C6 = 7.5 degrees) instead of staggered as expected from steric considerations. As a result, the pyrimidine ring and its 4,6-substituents are severely distorted from coplanarity. In DNMP, the 1-naphthalene ring is perpendicular to the pyrimidine ring (C8--C7--C5--C6 = -87.0 degrees) which is itself planar. N1 is protonated in DAMP-ES but not in DNMP. When the two structures are compared, the 5-substituents occupy different regions of space, with the outer ring of the naphthalene group outside of the volume occupied by the adamantyl ring. Therefore, the reduced effectiveness of DNMP may be caused by the inability of the naphthalene to fit the binding site in dihydrofolate reductase. This is the situation when DNMP is placed in the methotrexate binding site of Lactobacillus casei crystal structure.


Assuntos
Antineoplásicos , Antagonistas do Ácido Fólico , Pirimidinas/farmacologia , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Relação Estrutura-Atividade
16.
Hum Genet ; 56(1): 85-8, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7193643

RESUMO

The rate of spontaneous chromosomal aberrations in fibroblasts of a patient with Fanconi's anemia was slightly reduced after cocultivation with Chinese hamster ovary (CHO) cells. However, after mitomycin C treatment, a significant reduction of induced chromosomal damage was found in the FA cells while a significant increase was observed in the CHO cells. This antagonistic effect could be attributed to some diffusible agent(s). The results are discussed with respect to the underlying mechanism of the disease.


Assuntos
Anemia Aplástica/genética , Aberrações Cromossômicas , Cromossomos/efeitos dos fármacos , Anemia de Fanconi/genética , Células Híbridas/ultraestrutura , Mitomicinas/farmacologia , Adulto , Animais , Linhagem Celular , Células Cultivadas , Criança , Cricetinae , Cricetulus , Feminino , Humanos , Masculino , Ovário , Pele/ultraestrutura
18.
Hum Genet ; 56(1): 81-4, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7203484

RESUMO

Cells of patients with Fanconi's anemia (FA) are characterized by their high mitomycin C sensitivity. This specific response was used to study the question of heterogeneity in cell hybrids. After fusion of somatic cells of different FA patients and a normal control, the resulting hybrids were cytogenetically analyzed with respect to their mitomycin C susceptibility. Complementation--indicating heterogeneity--should lead to normal amounts of mitomycin C-induced chromosomal damage. No complementation was found in hybrids between cells of a classical FA patient and one without skeletal malformations. However, clear evidence for heterogeneity was observed in hybrids between cells of the latter patient with early onset and another with late onset of the disease. This confirms the assumption of Schroeder and coworkers based on the high intrafamilial correlation for age at onset.


Assuntos
Anemia Aplástica/genética , Aberrações Cromossômicas , Resistência a Medicamentos , Anemia de Fanconi/genética , Células Híbridas/efeitos dos fármacos , Mitomicinas/farmacologia , Adulto , Fatores Etários , Criança , Pré-Escolar , Cromossomos/efeitos dos fármacos , Teste de Complementação Genética , Humanos , Cariotipagem , Masculino
19.
Mol Gen Genet ; 175(2): 181-5, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-292826

RESUMO

Cell lines from Chinese hamster ovary [CHO-K1-D3] and human fibroblast cells [46, XX, 18p-] were mutagenized with N-nitrosomethylurea followed by a selection for cycloheximide resistance. Two mutants resistant against the drug were selected from either wildtype. 80S ribosomes and their ribosomal subunits were isolated from all mutant and wildtype cells. 80S ribosomes reassociated from the isolated subunits were as active as isolated 80S couples in the poly (U) dependent poly (Phe) synthesis. Hybrid 80S ribosomes constructed from subunits of the various cell lines of the same species were fully active, whereas the interspecies 80S hybrids were not active at all in poly (Phe) synthesis. Hybrid 80S ribosomes from subunits of mutant and the corresponding wildtype cells were tested in the poly (U) assay in the presence and absence of cycloheximide. The results strikingly indicate that in all four mutant cell lines the resistance against cycloheximide is conferred by the large subunit of cytoplasmic ribosomes.


Assuntos
Cicloeximida/farmacologia , Resistência a Medicamentos , Mutação , Ribossomos/metabolismo , Animais , Linhagem Celular , Cricetinae , Cricetulus , Feminino , Humanos , Ovário
20.
Hum Genet ; 50(3): 297-305, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-489015

RESUMO

Cycloheximide(CHM)-resistant mutant Chinese hamster ovary (CHO) and human cells were induced with N-nitrosomethylurea (NMU) and ethyl methanesulfonate (EMS); the mutants were viable and showed unlimited growth in the presence of CHM (7 X 10(-7) M), whereas this concentration inhibits protein synthesis in vivo as well as in vitro. No numerical or structural chromosomal aberrations were found in the mutant cells. In vitro analysis shows that the ribosomes confer resistance against cycloheximide.


Assuntos
Divisão Celular/efeitos dos fármacos , Cicloeximida/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , Animais , Linhagem Celular , Células Cultivadas , Aberrações Cromossômicas , Cricetinae , Resistência a Medicamentos , Metanossulfonato de Etila/farmacologia , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Humanos , Cariotipagem , Metilnitrosoureia/farmacologia , Mutação , Ovário
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