RESUMEN
SETTING: A referral hospital in South Africa.OBJECTIVE: To describe the clinical presentation, serial brain imaging findings during treatment and outcome of patients with intracranial tuberculoma in a high human immunodeficiency virus (HIV) prevalence setting.DESIGN: This was a retrospective observational study conducted over a 12.5-year period. Records of adults (age ≥18 years) who presented with neurological TB were screened. We included patients with tuberculoma in whom sequential brain imaging was performed.RESULTS: Of 66 patients enrolled, HIV status was known in 61; 47 (71%) were HIV-infected and 14 (21%) were non-HIV-infected. Clinical and imaging findings and outcomes were similar between these groups. Persistent tuberculoma was present at 18 months follow-up in 20/41 (49%) patients who underwent repeat imaging at that timepoint; those with persistent tuberculoma were more likely to have persisting neurological abnormalities (85% vs. 52%; P = 0.043). Larger tuberculoma size at presentation (≥3 cm) was the only factor significantly associated with tuberculoma persistence (multivariable logistic regression, OR 19.9, 95%CI 1.27-309.68; P = 0.033).CONCLUSION: Tuberculoma is a severely disabling TB manifestation regardless of HIV coinfection, with half of patients showing radiologically persistent lesions at 18 months follow-up. Large size of tuberculoma at presentation heralds lower chance of its resolution within 18 months.
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Coinfección , Infecciones por VIH , Tuberculoma Intracraneal , Tuberculoma , Adolescente , Adulto , Coinfección/epidemiología , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Prevalencia , Estudios Retrospectivos , Sudáfrica/epidemiología , Tuberculoma Intracraneal/diagnóstico por imagen , Tuberculoma Intracraneal/tratamiento farmacológicoRESUMEN
These consensus guidelines provide recommendations for the safe handling of monoclonal antibodies. Definitive recommendations are given for the minimum safe handling requirements to protect healthcare personnel. The seven recommendations cover: (i) appropriate determinants for evaluating occupational exposure risk; (ii) occupational risk level compared with other hazardous and non-hazardous drugs; (iii) stratification of risk based on healthcare personnel factors; (iv) waste products; (v) interventions and safeguards; (vi) operational and clinical factors and (vii) handling recommendations. The seventh recommendation includes a risk assessment model and flow chart for institutions to consider and evaluate clinical and operational factors unique to individual healthcare services. These guidelines specifically evaluated monoclonal antibodies used in the Australian cancer clinical practice setting; however, the principles may be applicable to monoclonal antibodies used in non-cancer settings. The guidelines are only applicable to parenterally administered agents.
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Anticuerpos Monoclonales/efectos adversos , Adhesión a Directriz , Personal de Salud , Exposición Profesional/prevención & control , Salud Laboral/normas , Preparaciones Farmacéuticas , Administración de la Seguridad/normas , Australia/epidemiología , Consenso , Femenino , Humanos , Masculino , Medición de RiesgoRESUMEN
BACKGROUND: IRF5 is a transcription factor involved both in the type I interferon and the toll-like receptor signalling pathways. Previously, IRF5 has been found to be associated with systemic lupus erythematosus, rheumatoid arthritis and inflammatory bowel diseases. Here we investigated whether polymorphisms in the IRF5 gene would be associated with yet another disease with features of autoimmunity, multiple sclerosis (MS). METHODS: We genotyped nine single nucleotide polymorphisms and one insertion-deletion polymorphism in the IRF5 gene in a collection of 2337 patients with MS and 2813 controls from three populations: two case-control cohorts from Spain and Sweden, and a set of MS trio families from Finland. RESULTS: Two single nucleotide polymorphism (SNPs) (rs4728142, rs3807306), and a 5 bp insertion-deletion polymorphism located in the promoter and first intron of the IRF5 gene, showed association signals with values of p<0.001 when the data from all cohorts were combined. The predisposing alleles were present on the same common haplotype in all populations. Using electrophoretic mobility shift assays we observed allele specific differences in protein binding for the SNP rs4728142 and the 5 bp indel, and by a proximity ligation assay we demonstrated increased binding of the transcription factor SP1 to the risk allele of the 5 bp indel. CONCLUSION: These findings add IRF5 to the short list of genes shown to be associated with MS in more than one population. Our study adds to the evidence that there might be genes or pathways that are common in multiple autoimmune diseases, and that the type I interferon system is likely to be involved in the development of these diseases.
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Predisposición Genética a la Enfermedad/genética , Factores Reguladores del Interferón/genética , Esclerosis Múltiple/genética , Mutación/genética , Población Blanca/genética , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Finlandia , Haplotipos , Humanos , Desequilibrio de Ligamiento/genética , Masculino , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genética , Factor de Transcripción Sp1/metabolismo , España , SueciaAsunto(s)
Víctimas de Crimen/estadística & datos numéricos , Violación/estadística & datos numéricos , Adolescente , Adulto , Anciano , Consejo , Femenino , Medicina Legal , Hospitales de Distrito , Humanos , Incidencia , Persona de Mediana Edad , Examen Físico , Sudáfrica/epidemiología , Encuestas y CuestionariosRESUMEN
The platinum(II) organoamides [Pt(NRCH2)2L2] (L = pyridine (py), R = p-HC6F4, C6F5,p-IC6F4,p-CIC6F4,p-C6F5C6F4; L = 4-methylpyridine, R = p-HC6F4) and [Pt(NRCH2CH2NR')(py)2] (R = p-HC6F4, R' = C6F5, p-BrC6F4, or p-MeC6F4) inhibit the growth of murine L1210 leukemia cells in culture with ID50 values for continuous exposure in the range 0.6-2.7 microM. Representative complexes are also active against L1210 cells in 2-h pulse exposures, as well as against the cisplatin-resistant variant L1210/DDP and human colonic carcinoma cell lines HT 29 and BE. Three complexes [Pt(NRCH2)2L2] (R = p-HC6F4, C6F5, or p-IC6F4) have good activity (T/C greater than or equal to 180%) against P388 leukemia in mice, and all other compounds tested are active except when R = p-C6F5C6F4, L = py. Although the molecular basis of the biological activity of these complexes is not known, the observation of good activity for amineplatinum(II) compounds with no hydrogen substituents on the nitrogen donor atoms introduces a new factor in the anticancer behavior of platinum(II) complexes.
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Antineoplásicos/farmacología , Compuestos Organoplatinos/farmacología , Animales , División Celular/efectos de los fármacos , Humanos , Ratones , Ratones Endogámicos DBA , Relación Estructura-Actividad , Células Tumorales Cultivadas/efectos de los fármacosRESUMEN
Our studies on the mechanism of resistance of the murine leukemia L1210-PDD line to cis-dichlorodiammineplatinum(II) (cis-DDP) have not shown why it is 10-fold more resistant to the drug than the L1210 line. For this reason we investigated metallothionein-like proteins ('MTs') in these cells. Soluble protein extracts from cultures treated for 24 h with cis-DDP, zinc sulphate or saline were anaerobically eluted from columns of chemically reduced Sephadex G-75, and the profiles of zinc, copper and platinum were determined along with those for incorporated radioactive cyst(e)ine and tyrosine. Both saline-treated cell lines contained similar levels of 'MTs', which were induced by exposure to a minimally toxic level of zinc (100 microM). Zinc induction of 'MTs' was nearly 4-fold greater in L1210 than in L1210-PDD cells. The levels of mRNA for metallothionein I (MTI) and II (MTII) in uninduced cells were measured by dot-blotting with a cDNA probe. The L1210-PDD cells contained 80% of the MTI and 41% of the MTII compared with L1210 cells, confirming the similar levels in uninduced cells. L1210-PDD cells were 2-fold more sensitive than L1210 cells to cadmium and equally sensitive to zinc. Thus, the resistance of L1210-PDD cells to cis-DDP was not associated with cross-resistance to group IIb metals, whereas their sensitivity to cadmium did reflect the relative inability of the cells to synthesize 'MTs'. The L1210 cells produced 'MTs' when treated with 0.5 and 5.0 microM cis-DDP, but the L1210-PDD cells did not when treated with 5.0-40 microM cis-DDP. Small amounts of platinum (less than 21% of the total eluted) were bound to 'MTs' in both cell lines, but platinum provided a minor portion of the 'MT'-bound metals, with zinc and copper contributing the bulk. The basis for the resistance of L1210-PDD cell to cis-DDP is neither an increased level of 'MTs' in the resistant cells nor an enhanced ability to increase the synthesis of 'MTs' after drug exposure.
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Cisplatino/farmacología , Leucemia L1210/metabolismo , Metalotioneína/metabolismo , Animales , Cadmio/farmacología , Cobre/metabolismo , Resistencia a Medicamentos , Leucemia L1210/genética , Leucemia L1210/patología , Metalotioneína/biosíntesis , Metalotioneína/genética , Ratones , Platino (Metal)/metabolismo , ARN Mensajero/análisis , ARN Neoplásico/análisis , Sulfatos/farmacología , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/patología , Zinc/metabolismo , Zinc/farmacología , Sulfato de ZincRESUMEN
cis-Dichlorodiammineplatinum(II) (cis-DDP) doubled the amount of metallothioneins (MTs) in the livers and kidneys of BALB/c mice when injected i.p. in a single high dose of 30 mumol/kg (9 mg/kg). Two such doses given 17 h apart increased hepatic MTs 5-fold and also increased the relative rate of incorporation of radiolabelled cyst(e)ine into hepatic MTs. Hydrolysed cis-DDP was more effective than cis-DDP, increasing MT-bound zinc 27-fold and [3H]cysteine incorporation 6-fold in liver while doubling each of these in kidney. The MTs from the livers of mice treated with cis-DDP bound zinc, copper and platinum in ratios of 5:1:0.3, respectively, similar to those in whole liver and its soluble fraction, indicating that MTs do not selectively sequester platinum under these circumstances. The effects of cis-DDP on zinc and copper levels in serum, liver and kidney suggest that induction of MTs by cis-DDP is not mediated by displacement of endogenous zinc. Indirect induction by corticosteroids secreted in a stress response to cis-DDP is also an unlikely cause. cis-DDP, probably in a hydrolysed form, can therefore induce and bind to MTs in normal tissues, particularly when given at repeated high dosage.
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Cisplatino/análogos & derivados , Cisplatino/farmacología , Hígado/metabolismo , Metalotioneína/biosíntesis , Animales , Cromatografía en Gel , Hígado/efectos de los fármacos , Masculino , Metalotioneína/aislamiento & purificación , Ratones , Ratones Endogámicos BALB C , Valores de Referencia , Sulfatos/farmacología , Zinc/farmacología , Sulfato de ZincRESUMEN
A small animal model for emesis would allow preclinical testing of antiemetics and new drugs. Mice treated with cisplatinum develop stomachs distended with food. This effect is reduced by metoclopramide and parallels the gastric nausea experienced by patients receiving cisplatinum. To assess gastric distension as a more general model for paralleling the human emetic response, groups of five BALB/c mice were given intravenous nitrogen mustard, adriamycin, cyclophosphamide, 5-fluoruracil (5FU), vincristine and intraperitoneal DTIC at doses equivalent to those used clinically (mg/kg mouse = 12 X mg/kg per man). The mice were allowed free access to food pellets and water. At 48 h they were sacrificed and gastric distension quantitated as a ratio of average stomach to body weight. Significant gastric distension occurred with nitrogen mustard, DTIC, adriamycin and cyclophosphamide but not 5FU or vincristine. This parallels the emetic potential of these drugs in humans. Similarly cisplatinum was compared to its analogues, carboplatin and JM40 and produced gastric distension at lower doses than carboplatin. The model was then used to test the antiemetic efficacy of escalating doses of prochlorperazine against cisplatinum induced gastric distension in groups of 10 BALB/c mice. Doses ranged from 2.5 mg/kg. Only a high dose (19.2 mg/kg) significantly reduced the gastric distension. This parallels a clinical dose response relationship recently reported for prochlorperazine and suggests the further potential use of this model.
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Antieméticos/farmacología , Antineoplásicos/farmacología , Eméticos , Estómago/fisiología , Animales , Cisplatino/farmacología , Ratones , Ratones Endogámicos , Proclorperazina/farmacología , Valores de Referencia , Estómago/efectos de los fármacosRESUMEN
The binding of platinum (II)-terpyridine complexes to DNA was studied by using equilibrium dialysis. Optical absorption methods were used to measure the ability of the ligands to aggregate in aqueous buffer. Scatchard plots for the binding of the monomeric [Pt(terpy)SC4H9]+ cation to DNA at I0.01 are curvilinear, concave upwards, suggesting two modes of binding. The association constant decreases at higher ionic strengths, consistent with polyelectrolyte theory, and 1.1 cations are released per bound ligand molecule. The association constants of the binuclear ligands [Pt(terpy)S[CH2]4S(terpy)Pt]2+ and [Pt(terpy)S[CH2]6S(terpy)Pt]2+ are 8 and 23 times larger respectively than the affinity of the monomer. For the latter binuclear derivative the increase may be ascribed to bifunctional reaction. Differential dialysis experiments with DNAs of differing base composition show that [Pt(terpy)SC4H9]+ has a requirement for a single G X C base-pair at the highest-affinity site. However, in the binuclear ligands chromophore specificity is severely compromised. Similar experiments indicate that 9-aminoacridine and selected methylene-linked diacridines show no significant sequence selectivity.
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ADN/metabolismo , Compuestos Organoplatinos/metabolismo , Piridinas/metabolismo , Animales , Sitios de Unión , Bovinos , ADN Bacteriano/metabolismo , Ligandos , Sustancias MacromolecularesRESUMEN
This study investigates the effects of adrenergic agonists and mitochondrial energy state on the activities of the Ca2+ transport systems of female rat liver mitochondria. Tissue perfusion with the alpha-adrenergic agonist phenylephrine and with adrenaline, but not with the beta-adrenergic agonist isoprenaline, induced significant activation of the uniporter and the respiratory chain. Uniporter activation was evident under two sets of experimental conditions that excluded influences of delta psi, i.e., at high delta psi, where uniporter activity was delta psi independent, and at low delta psi, where uniporter conductance was measured. Preincubation of mitochondria with extracts from phenylephrine-perfused tissue quantitatively reproduced uniporter activation when comparison was made with mitochondria treated similarly with extracts from tissue perfused without agonist. Similar, but more extensive, data were obtained with heart mitochondria pretreated with extracts from hearts perfused with the alpha-adrenergic agonist methoxamine. Phenylephrine did not affect Ca2+ efflux mediated by the Na+-Ca2+ carrier or the Na+-independent system. In contrast, the liver mitochondrial Na+-Ca2+ carrier was activated by tissue perfusion with isoprenaline; the Na+-independent system was unaffected. Na+-Ca2+ carrier activation was not associated with any change in a number of basic bioenergetic parameters. It is concluded that the Ca2+ transport systems of liver mitochondria may be controlled in an opposing manner by alpha-adrenergic agonists (promotion of Ca2+ influx) and beta-adrenergic agonists (promotion of Ca2+ efflux). At delta psi values greater than 110 mV, the Na+-independent system was activated by increase in delta psi; the uniporter and Na+-Ca2+ carrier activities were insensitive to delta psi changes in this range.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
ATPasas Transportadoras de Calcio/metabolismo , Calcio/metabolismo , Epinefrina/farmacología , Isoproterenol/farmacología , Mitocondrias Cardíacas/metabolismo , Mitocondrias Hepáticas/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Fenilefrina/farmacología , Animales , Carbonil Cianuro m-Clorofenil Hidrazona/farmacología , Conductividad Eléctrica , Femenino , Corazón/fisiología , Concentración de Iones de Hidrógeno , Cinética , Hígado/fisiología , Mitocondrias Cardíacas/efectos de los fármacos , Mitocondrias Hepáticas/efectos de los fármacos , Ratas , Ratas Endogámicas , Extractos de Tejidos/farmacologíaRESUMEN
Arginine-vasopressin (AVP) in the presence of Mg2+ but not in the absence of bivalent cations led to accumulation of [32P]-phosphatidic acid [( 32P]-PA) in human blood platelets. Mg2+ also enhanced the specific binding of [3H]-AVP to intact platelets. The concentrations of the cation which enabled AVP to cause half maximal rise of [32P]-PA and those inducing half maximal [3H]-AVP-binding were of the same order. It is concluded that the stimulation of phosphatidyl inositide breakdown by AVP in presence of Mg2+ is at least partially due to a Mg2+-induced enhancement of specific AVP-binding to the platelet membranes.
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Plaquetas/efectos de los fármacos , Magnesio/fisiología , Vasopresinas/farmacología , Arginina Vasopresina/metabolismo , Arginina Vasopresina/farmacología , Plaquetas/metabolismo , Membrana Celular/efectos de los fármacos , Humanos , Ácidos Fosfatidicos/metabolismo , Radioisótopos de Fósforo , Unión Proteica , Vasopresinas/metabolismoRESUMEN
A series of binuclear DNA-binding ligands was prepared by linking two (2,2':6',2"-terpyridine)platinum(II) moieties via alpha omega-dithiols of the type HS-[CH2]n-SH where n = 4-10. A monomeric analogue was also synthesized. Compounds were characterized by elemental analysis and electronic and n.m.r. spectroscopy. Viscometric measurements with sonicated rod-like DNA fragments and covalently closed circular DNA were performed to investigate the mode of binding of these agents. The ligands with n = 5 and 6 function as bis intercalators and form a single 'base-pair sandwich' in violation of neighbour-exclusion binding. Bifunctional reaction occurs for the ligand with n = 7, whereas the ligands with n = 8 and 10 show a preference for mixed monofunctional/bifunctional binding. The data do not permit definitive assignment of the binding mode of the ligands with n = 4 and 9. All compounds are growth-inhibitory against mouse leukaemia L1210 cells in culture with IC50 values in the range 2-14 microM.
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Sustancias Intercalantes , Compuestos Organoplatinos/farmacología , Piridinas/farmacología , Animales , Bovinos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , ADN Circular/efectos de los fármacos , Sustancias Intercalantes/farmacología , Ligandos , Sustancias Macromoleculares , Espectroscopía de Resonancia Magnética , Espectrofotometría , ViscosidadRESUMEN
For a series of 9-aminoacridinecarboxamides, anti-tumour activity in vivo and cytotoxicity in vitro are correlated directly with the ability of the compounds to cause DNA single-strand breaks and with their DNA-dissociation mechanisms and residence times. It is suggested that one important consequence of long DNA residence times may be an enhanced ability to cause DNA strand breaks by a non-oxidative mechanism.
Asunto(s)
Aminoacridinas/farmacología , Antineoplásicos/farmacología , Daño del ADN , ADN/metabolismo , Relación Dosis-Respuesta a Droga , Enlace de Hidrógeno , Cinética , Relación Estructura-Actividad , Células Tumorales Cultivadas/efectos de los fármacosRESUMEN
Four series of intercalating, square-planar Pt(II) complexes derived from the ligands 2,2'-bipyridine, 2,2':6',2"-terpyridine, 1,10-phenanthroline, and 3,4,7,8-tetramethyl-1,10-phenanthroline were synthesized and aspects of their activity against murine leukemia L1210 cells investigated. The 2,2':6',2"-terpyridine-thiolato complexes are growth inhibitory in culture, with IC50 values in the range 6-32 microM, and cause cell lysis at high concentrations. Of the remaining three series, the 2,2'-bipyridine complexes are the least potent in their effects. There is a general enhancement in activity on moving from the 1,10-phenanthroline complexes to the 3,4,7,8-tetramethyl-1,10-phenanthroline analogues. Flow cytometric analysis on representative complexes shows that they are not cell cycle specific. Alkaline elution experiments indicate no damage to DNA of cells exposed to (thiophenolato)(2,2':6',2"-terpyridine)platinum(II) chloride monohydrate and (ethylenediamine)(1,10-phenanthroline)platinum(II) dichloride dihydrate although (ethylenediamine)(3,4,7,8-tetramethyl-1,10-phenanthroline)platinum(II) dichloride dihydrate causes both single-strand breaks and DNA cross-links. Compounds 2a, 5a, and 6a showed no antitumor activity against L1210 in mice.
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Antineoplásicos/síntesis química , Sustancias Intercalantes/síntesis química , Leucemia L1210/tratamiento farmacológico , Compuestos Organoplatinos/farmacología , Animales , División Celular/efectos de los fármacos , Células Cultivadas , ADN de Neoplasias/metabolismo , Leucemia L1210/metabolismo , Masculino , Ratones , Compuestos Organoplatinos/síntesis química , Relación Estructura-ActividadRESUMEN
A method of interfacing an inexpensive microcomputer to a stopped-flow kinetics spectrophotometer is described. It allows software-selectable sampling frequencies between 0.1 ms and 8 s and large numbers of data points to be collected. Machine language routines to use the interface are described and these allow the sampling frequency to be altered during data collection to ensure adequate numbers of points in critical regions of the kinetic profile. BASIC programs for collection and analysis of multicomponent kinetic data using this system are also described. Due to the large number of data points that can be collected and the ability to selectively sample transmittance values in regions where the signal is rapidly changing with time, relatively unsophisticated methods of data analysis can be used. These methods are suitable for use by microcomputers and mean that data analysis and acquisition can be performed on the same microcomputer in real time. To illustrate this, multicomponent analysis of kinetic transients is performed on simulated data and on the dissociation kinetics of the ethidium-DNA complex.
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Espectrofotometría Ultravioleta/instrumentación , Automatización , Computadores , ADN , Etidio , CinéticaRESUMEN
The intracellular DNA damage produced by a series of diacridines after a 2 h pulse treatment of L1210 cells in culture was investigated by using the alkaline-elution technique. Like other intercalating agents, diacridines produce single-strand breaks and protein-DNA links. There is a large increase in both types of damage as the alkane chain linking the two 9-aminoacridine residues is increased beyond five methylene groups, which is consistent with the previously observed change from monofunctional to bifunctional intercalation [Wakelin, Romanos, Chen, Glaubiger, Canellakis & Waring (1978) Biochemistry 17, 5057-5063]. For linker chains of less than six methylene groups these agents produce less DNA damage than does the parent 9-aminoacridine at the same drug concentration. Unlike the monofunctional intercalators previously investigated [Ross, Glaubiger & Kohn (1979) Biochim. Biophys. Acta 562, 41-50; Zwelling, Michaels, Erickson, Ungerleider, Nichols & Kohn (1981) Biochemistry 20, 6553-6563; Zwelling, Kerrigan & Michaels (1982) Cancer Res. 42, 2687-2691; Zwelling, Michaels, Kerrigan, Pommier & Kohn (1982) Biochem. Pharmacol. 31, 3261-3267], there is no correlation between the number of single-strand breaks and protein-DNA links produced by these diacridines.
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Acridinas/farmacología , ADN/metabolismo , Sustancias Intercalantes/farmacología , Álcalis , Animales , División Celular/efectos de los fármacos , Células Cultivadas , Fenómenos Químicos , Química , Leucemia L1210/metabolismo , Sustancias Macromoleculares , Ratones , Proteínas/metabolismoRESUMEN
The interaction between a novel aromatic thiolato derivative from the family of DNA-intercalating platinum complexes, phenylthiolato-(2,2',2"-terpyridine)platinum(II)-[PhS(ter py)Pt+], and nucleic acids was studied by using viscosity, equilibrium-dialysis and kinetic measurements. Viscosity measurements with sonicated DNA provide direct evidence for intercalation, and show that at binding ratios below 0.2 molecules per base-pair PhS(terpy)Pt+ causes an increase in contour length of 0.2 nm per bound molecule. However, helix extension diminishes at greater extents of binding, indicating the existence of additional, non-intercalated, externally bound forms of the ligand. The ability of PhS(terpy)Pt+ to aggregate in neutral aqueous buffers at a range of ionic strengths and temperatures was assessed by using optical-absorption methods. Scatchard plots for binding to calf thymus DNA at ionic strength 0.01 (corrected for dimerization) are curvilinear, concave upward, providing further evidence for two modes of binding. The association constant decreases at higher ionic strengths, in accord with the expectations of polyelectrolyte theory, although the number of cations released per bound unipositive ligand molecule is substantially greater than 1. Stopped-flow kinetic measurements confirm the complexity of the binding reaction by revealing multiple bound forms of the ligand whose kinetic processes are both fast and closely coupled. Thermal denaturation of DNA radically alters the shapes of binding isotherms and either has little effect on, or enhances, the affinity of potential binding sites, depending on experimental conditions. Scatchard plots for binding to natural DNA species with differing nucleotide composition show that the ligand has a requirement for a single G X C base-pair at the highest-affinity intercalation sites.
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ADN , Compuestos Organoplatinos , Animales , Composición de Base , Bovinos , ADN Bacteriano , Diálisis , Calor , Cinética , Sustancias Macromoleculares , Desnaturalización de Ácido Nucleico , Termodinámica , Timo/análisis , ViscosidadRESUMEN
In this study the relation between three kinds of diagnostic data and the eventual referral advice to a psychogeriatric nursing-home is investigated. It concerns the results of behaviour observation according to the BOP (a Dutch geriatric rating scale), psychological test scores and social-biographical data. The emphasis is on the evaluation of the tests. The research sample consists of 63 aged observation or day-care patients. The results of a multiple regression-analysis indicate that the BOP-scores have the highest predictive value for the referral advice. The psychological tests hardly add anything to this. However, as a group on their own, the tests explain a reasonable part of the variance in the advice. This result, added to the high correlations between test- and BOP-scores, indicates the value of psychological testing, especially when observation data are lacking. Finally, suggestions are made for further studies in this area.
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Trastornos Mentales/diagnóstico , Pruebas Psicológicas/normas , Actividades Cotidianas , Anciano , Femenino , Humanos , Masculino , Psicometría , Derivación y Consulta , Análisis de RegresiónRESUMEN
Two lines of human colonic carcinoma cells have different sensitivities to 5-fluorouracil and 1-(2-chlorethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (methyl-CCNU). The growth of the BE line is 50% inhibited by 330 microM 5-fluorouracil and 15 microM methyl-CCNU, and the HT-29 line is 50% inhibited by 85 and 140 microM, respectively. On cloning, 50% of BE cells are killed by 500 microM 5-fluorouracil and 6 microM methyl-CCNU, and the HT-29 cells are killed by 250 and 120 microM respectively. When the drugs were combined, there were additive effects which occurred in cell growth of both lines and killing of BE cells. Synergism occurred in killing HT-29 cells when a low concentration of 5-fluorouracil was combined with methyl-CCNU. The synergism did not increase with increasing concentrations of 5-fluorouracil. Both drugs caused growth delay of spheroids (HT-29 cells), an effect that was additive when the drugs were combined. Growth inhibition of both lines in monolayer culture by 5-fluorouracil was more sensitive than was cell killing or inhibition of spheroid growth but, with methyl-CCNU, killing of BE cells was more sensitive than was growth inhibition. HT-29 cells showed similar sensitivity to methyl-CCNU in all three systems. The type and sensitivity of drug effect seen in vitro depends on the particular drug used, the cell line tested, and the parameter measured.