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1.
Ann Oncol ; 27(4): 673-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26747859

RESUMEN

BACKGROUND: The phase III RAINBOW trial demonstrated that the addition of ramucirumab to paclitaxel improved overall survival, progression-free survival, and tumor response rate in fluoropyrimidine-platinum previously treated patients with advanced gastric/gastroesophageal junction (GEJ) adenocarcinoma. Here, we present results from quality-of-life (QoL) and performance status (PS) analyses. PATIENTS AND METHODS: Patients with Eastern Cooperative Oncology Group PS of 0/1 were randomized to receive ramucirumab (8 mg/kg i.v.) or placebo on days 1 and 15 of a 4-week cycle, with both arms receiving paclitaxel (80 mg/m(2)) on days 1, 8, and 15. Patient-reported outcomes were assessed with the QoL/health status questionnaires EORTC QLQ-C30 and EQ-5D at baseline and 6-week intervals. PS was assessed at baseline and day 1 of every cycle. Time to deterioration (TtD) in each QLQ-C30 scale was defined as randomization to first worsening of ≥10 points (on 100-point scale) and TtD in PS was defined as first worsening to ≥2. Hazard ratios (HRs) for treatment effect were estimated using stratified Cox proportional hazards models. RESULTS: Of the 665 patients randomized, 650 (98%) provided baseline QLQ-C30 and EQ-5D data, and 560 (84%) also provided data from ≥1 postbaseline time point. Baseline scores for both instruments were similar between arms. Of the 15 QLQ-C30 scales, 14 had HR < 1, indicating similar or longer TtD in QoL for ramucirumab + paclitaxel. Treatment with ramucirumab + paclitaxel was also associated with a delay in TtD in PS to ≥2 (HR = 0.798, P = 0.0941). Alternate definitions of PS deterioration yielded similar results: PS ≥ 3 (HR = 0.656, P = 0.0508), deterioration by ≥1 PS level (HR = 0.802, P = 0.0444), and deterioration by ≥2 PS levels (HR = 0.608, P = 0.0063). EQ-5D scores were comparable between treatment arms, stable during treatment, and worsened at discontinuation. CONCLUSION: In patients with previously treated advanced gastric/GEJ adenocarcinoma, addition of ramucirumab to paclitaxel prolonged overall survival while maintaining patient QoL with delayed symptom worsening and functional status deterioration. CLINICALTRIALSGOV: NCT01170663.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Anticuerpos Monoclonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias Esofágicas/tratamiento farmacológico , Paclitaxel/administración & dosificación , Adenocarcinoma/patología , Adulto , Anciano , Anticuerpos Monoclonales Humanizados , Supervivencia sin Enfermedad , Neoplasias Esofágicas/patología , Unión Esofagogástrica/efectos de los fármacos , Unión Esofagogástrica/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Resultado del Tratamiento , Ramucirumab
3.
Onkologie ; 27(5): 462-6, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15585976

RESUMEN

AIM: Objective of this study was to evaluate the hemoglobin level (Hb) as potential prognostic factor in uniformly staged patients (pts) undergoing primary chemoradiotherapy (ChRT) for locally advanced squamous cell carcinoma (SCC) of the esophagus. PATIENTS AND METHODS: Pts with histologically proven SCC of the esophagus (uT3/4 Nx or uTx N+) were included in the analysis. Staging procedures comprised endoscopic ultrasound, barium swallow and computed tomography. All pts received radiotherapy (> or =40 Gy) and > or =2 courses of fluorouracil/folinic acid, and cisplatin (5 days/month). In selected pts surgical resection after neoadjuvant ChRT was carried out. Clinical parameters, especially Hb were retrospectively evaluated for their impact on survival. RESULTS: 46 pts were treated between 1996 and 2001. Median survival was 16 months. Survival for pts treated with definitive ChRT (n = 28) was 14 months, whereas pts treated surgically after neoadjuvant ChRT (n = 18) survived 19 months (p = 0.79). Pts with low Hb levels at baseline did not show a worse outcome in comparison with pts with normal Hb levels (16 months), whereas a significant decrease in Hb level within the time period of ChRT was associated with a significantly inferior outcome (11 vs. 31 months; p = 0.046). Pts requiring blood transfusion tended to have inferior survival (11 vs. 24 months; p = 0.07). CONCLUSION: In this retrospective analysis a significant decrease of Hb level during ChRT was identified as prognostic factor for pts undergoing ChRT of SCC of the esophagus.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Biomarcadores de Tumor/sangre , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/terapia , Hemoglobinas/análisis , Anciano , Anemia/sangre , Anemia/diagnóstico , Anemia/epidemiología , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Causalidad , Cisplatino/administración & dosificación , Terapia Combinada , Comorbilidad , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/patología , Femenino , Fluorouracilo/administración & dosificación , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Radioterapia/métodos , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
4.
Undersea Hyperb Med ; 30(2): 87-91, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12964852

RESUMEN

In 1936 Lemierre described an aggressive neck infection with a high mortality rate. In the original characterization, he describes a pharyngotonsillitis and/or peritonsillar infection followed by unilateral swelling and tenderness along the sternocleidomastoid muscle owing to septic thrombophlebitis of the internal jugular vein. Subsequent to invasion and thrombophlebitis of the internal jugular vein, Fusobacterium necrophorum septicemia occurs, with rigors, high fever, and septic thromboembolism to peripheral sites, especially the lungs and bones. This entity became known as Lemierre Syndrome. Hyperbaric Oxygen (HBO2) has been described as adjunctive treatment in two cases of postanginal septicemia. This case describes the combined approach to a case of Lemierre Syndrome in which HBO2 was added as an adjunct to the treatment, with a favorable and rapid improvement in the patient's condition.


Asunto(s)
Infecciones por Fusobacterium/terapia , Fusobacterium necrophorum , Oxigenoterapia Hiperbárica/métodos , Enfermedades Pulmonares/terapia , Faringitis/terapia , Tonsilitis/terapia , Adolescente , Infecciones por Fusobacterium/diagnóstico por imagen , Infecciones por Fusobacterium/microbiología , Humanos , Venas Yugulares/diagnóstico por imagen , Enfermedades Pulmonares/diagnóstico por imagen , Enfermedades Pulmonares/microbiología , Masculino , Cuello , Faringitis/diagnóstico por imagen , Faringitis/microbiología , Radiografía , Síndrome , Tromboembolia/diagnóstico por imagen , Tromboembolia/terapia , Tonsilitis/diagnóstico por imagen , Tonsilitis/microbiología
5.
Leukemia ; 14(6): 998-1005, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10865964

RESUMEN

The degree of tumor load reduction after therapy is an important prognostic factor for patients with CML. Conventional metaphase analysis has been considered to be the 'gold standard' for evaluating patient response to treatment but this technique normally requires bone marrow aspiration and is therefore invasive. The frequency of cytogenetic analyses can be considerably reduced if patients are also monitored by molecular methods, which can be performed on peripheral blood specimens. Of the various techniques available, most attention has been paid to RT-PCR for BCR-ABL mRNA since this is by far the most sensitive. Simple, non-quantitative RT-PCR analysis gives only limited information on patients after treatment. Quantitative RT-PCR assays have been developed to monitor the kinetics of residual BCR-ABL transcripts over time. Variables in the quantitative PCR assay may be controlled for by quantification of transcripts of a normal gene (eg ABL or glucose-6-phosphate dehydrogenase, G6PD) as an internal standard. After allogeneic stem cell transplantation, most patients become RT-PCR negative, often after a period of low level positivity that may persist for several months. Those patients destined to relapse are characterized by the reappearance and/or rising levels of BCR-ABL transcripts. In contrast, for patients treated with interferon-alpha (IFN) residual disease is rarely, if ever, eliminated. The actual level of minimal residual disease in complete cytogenetic responders to IFN correlates with the probability of relapse. New quantitative real time procedures promise to simplify the protocols that are currently in use, but standardization and the introduction of rigorous, internationally accepted controls are required to enable RT-PCR to become a robust and routine basis for therapeutic decisions.


Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Neoplasia Residual/diagnóstico , Proteínas de Fusión bcr-abl/genética , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Neoplasia Residual/genética , Neoplasia Residual/patología , ARN Mensajero/genética , Recurrencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
6.
Blood ; 95(1): 62-6, 2000 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-10607685

RESUMEN

A substantial minority of patients with chronic myelogenous leukemia (CML) achieve a complete response (CR) to treatment with interferon-alpha (IFN), defined as the disappearance of Philadelphia chromosome-positive metaphases. Currently it is unclear how long IFN treatment should be continued for such patients. We used a competitive reverse transcriptase-polymerase chain reaction (RT-PCR) to quantify levels of BCR-ABL transcripts in 297 peripheral blood specimens collected from 54 patients who had achieved CR with IFN. The median duration of observation was 1.9 years (range, 0.3-11.0 years). Total ABL transcripts were quantified as internal control and results were expressed as the ratio BCR-ABL/ABL. All 54 patients had molecular evidence of residual disease, although 3 patients were intermittently PCR negative. The median BCR-ABL/ABL ratio at the time of maximal response for each patient was 0.045% (range, 0%-3. 6%). During the period of observation 14 patients relapsed, 11 cytogenetically to chronic phase disease and 3 directly to blastic phase. The median ratio of BCR-ABL/ABL at maximal response was significantly higher in patients who relapsed than in those who remained in CR (0.49% versus 0.021%, P < 0.0001). Our findings show that the level of residual disease falls with time in complete responders to IFN, but molecular evidence of disease is rarely if ever eliminated. The actual level of minimal residual disease correlates with the probability of relapse. We suggest that for patients who reach CR, IFN should be continued at least until relatively low levels of residual leukemia are achieved. (Blood. 2000;95:62-66)


Asunto(s)
Proteínas de Fusión bcr-abl/genética , Interferón-alfa/uso terapéutico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Proteínas de Fusión bcr-abl/sangre , Humanos , Interferón alfa-2 , Leucemia Mielógena Crónica BCR-ABL Positiva/sangre , Masculino , Persona de Mediana Edad , Neoplasia Residual , Proteínas Proto-Oncogénicas c-abl/genética , Proteínas Recombinantes , Recurrencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo , Transcripción Genética
7.
Leukemia ; 13(11): 1825-32, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10557058

RESUMEN

We sought to establish a rapid and reliable RT-PCR approach for detection and quantification of BCR-ABL fusion transcripts using the LightCycler technology. This device combines rapid thermocycling with online detection of PCR product formation and is based on the fluorescence resonance energy transfer (FRET) between two adjacent hybridization probes carrying donor and acceptor fluorophores. A pair of probes was designed that was complementary to ABL exon 3, thus enabling detection of all known BCR-ABL variants and also normal ABL as an internal control. Conditions were established to amplify less than 10 target molecules/reaction and to detect one CML cell in 105 cells from healthy donors. To determine the utility of the assay, we quantified BCR-ABL and ABL transcripts in 254 samples (222 peripheral blood, 32 bone marrow) from 120 patients with CML after therapy with IFN-alpha (n = 219), allogeneic BMT (n = 17), chemotherapy (n = 11), or at diagnosis (n = 7). The level of residual disease in the 245 BCR-ABL positive specimens was expressed as the ratio of BCR-ABL/ABL. This ratio was compared to results obtained by three established methods from contemporaneous specimens. A highly significant correlation was seen between the BCR-ABL/ABL ratios determined by the LightCycler and (1) the BCR-ABL/ABL ratios obtained by nested competitive RT-PCR (n = 201, r = 0.90, P < 0. 0001); (2) the proportion of Philadelphia chromosome positive metaphases determined by cytogenetics (n = 81, P < 0.0001); and (3) the BCR ratio determined by Southern blot analysis (n = 122, P < 0. 0001). We conclude that real-time PCR with hybridization probes is a reliable and sensitive method to monitor CML patients after therapy. The major advantages of the methodology are (1) amplification and product analysis are performed in the same reaction vessel, avoiding the risk of contamination; (2) the results are standardized by the quantification of housekeeping genes; and (3) the complete PCR analysis takes less than 60 min.


Asunto(s)
Proteínas de Fusión bcr-abl/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Southern Blotting , Análisis Citogenético , Sondas de ADN , Exones/genética , Femenino , Fluorescencia , Colorantes Fluorescentes , Genes abl/genética , Glucosafosfato Deshidrogenasa/genética , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Masculino , Mutación/genética , ARN Mensajero/análisis , ARN Mensajero/genética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Anticancer Res ; 18(2A): 829-31, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9615727

RESUMEN

Former studies revealed musk ambrette as a mutagen in Salmonella typhimurium TA 100 in the presence (+S9) but not in the absence (-S9) of an exogenous metabolizing system. To clarify the role of bacterial nitroreductases (NR) in the toxification of musk ambrette to mutagenic metabolites the compound was examined with the Salmonella/mammalian microsome assay using the NR deficient strain S.typhimurium TA 100 NR in the presence and absence of S9. Musk ambrette showed mutagenicity in Salmonella typhimurium TA 100 (+S9) but no mutagenicity in the NR deficient strain TA 100 NR (+S9). Additionally, no mutagenicity was detected in both TA 100 (-S9) and TA 100 NR (-S9). These results indicate the need for both mammalian microsomal enzymes and bacterial nitroreductases to cause the mutagenicity of musk ambrette.


Asunto(s)
Dinitrobencenos/toxicidad , Microsomas Hepáticos/metabolismo , Mutágenos/toxicidad , Nitrorreductasas/fisiología , Salmonella typhimurium/enzimología , Dinitrobencenos/metabolismo
9.
J Bacteriol ; 180(9): 2337-44, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9573183

RESUMEN

Bacterial three-component dioxygenase systems consist of reductase and ferredoxin components which transfer electrons from NAD(P)H to a terminal oxygenase. In most cases, the oxygenase consists of two different subunits (alpha and beta). To assess the contributions of the alpha and beta subunits of the oxygenase to substrate specificity, hybrid dioxygenase enzymes were formed by coexpressing genes from two compatible plasmids in Escherichia coli. The activities of hybrid naphthalene and 2,4-dinitrotoluene dioxygenases containing four different beta subunits were tested with four substrates (indole, naphthalene, 2,4-dinitrotoluene, and 2-nitrotoluene). In the active hybrids, replacement of small subunits affected the rate of product formation but had no effect on the substrate range, regiospecificity, or enantiomeric purity of oxidation products with the substrates tested. These studies indicate that the small subunit of the oxygenase is essential for activity but does not play a major role in determining the specificity of these enzymes.


Asunto(s)
Proteínas Hierro-Azufre/metabolismo , Complejos Multienzimáticos/metabolismo , Oxigenasas/metabolismo , Burkholderia/enzimología , Dinitrobencenos/metabolismo , Dioxigenasas , Escherichia coli/genética , Indoles/metabolismo , Proteínas Hierro-Azufre/genética , Complejos Multienzimáticos/genética , Naftalenos/metabolismo , Naftoles/metabolismo , Oxidación-Reducción , Oxigenasas/genética , Pseudomonas/enzimología , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Especificidad por Sustrato , Tolueno/análogos & derivados
10.
Mutat Res ; 356(2): 237-45, 1996 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-8841491

RESUMEN

In the present study, musk xylene (MX) and musk ketone (MK) were examined for their potency to induce toxifying enzymes in the liver of Sprague-Dawley rats, using an in vivo/in vitro model. After i.p. application of 10, 20 and 40 mg/day MX and MK over a period of 5 days, 9000 x g liver fractions (S9M) were used to study the toxification of a number of well-known pregenotoxicants in the SOS chromotest, i.e., benzo[a]pyrene (B[a]P), 2-aminoanthracene (2-AA), and aflatoxin B1 (AFB1). The genotoxic potencies of B[a]P, 2-AA and AFB1 in the presence of S9M were compared to those obtained in the presence of S9 fractions of untreated animals (S9O, negative control). S9M fractions derived from MK-treated rats showed an increased potency to toxify B[a]P, 2-AA and AFB1 in comparison to S9O fractions (for instance: TIP[toxifying induction potency] = 70 per nmol AFB1 using 10 mg MK treatment). In comparison, S9M fractions from MX-pretreated rats exhibited an increased genotoxicity only when using 2-AA (TIP = 0.04) and AFB1 (TIP = 61) as pregenotoxicants, but not when using B[a]P. To summarize the results, both MX and MK were strong inducers of toxifying liver enzymes. Therefore, these compounds seem to be cogenotoxicants for a number of well-known pregenotoxicants. Synergistic effects were found when using inducers of toxifying enzymes and pregenotoxicants in the in vivo/in vitro induction model.


Asunto(s)
Inducción Enzimática , Hígado/enzimología , Xilenos/farmacología , Animales , Escherichia coli/genética , Masculino , Ratas , Ratas Sprague-Dawley , Respuesta SOS en Genética
11.
Gesundheitswesen ; 58(7): 400-5, 1996 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-8963106

RESUMEN

In the present study a mixture containing the 11 PCB major components identified in fatty tissues of children was examined for its potency to enhance the toxification of pregenotoxicants (cogenotoxicity) in the liver. As a basis for the study GC/MS PCB analyses of 207 fatty tissue samples of children were used. The PCB mixture was produced on this basis. As a model for the identification of the cogenotoxic potency of the PCB mixtures an in vivo/in vitro enzyme induction assay was developed. The goal of the study was to clarify the question, whether the in vivo pretreatment of rats with a complex PCB pattern derived from children led to a synergism of cogenotoxicants and pregenotoxicants with regard to the enhancement of the in vitro toxification of benzo[a]pyrene (B[a]P) and 2-aminoanthracene (2-AA) to DNA reactive metabolites. Using the SOS-Chromotest as the in vitro part of the induction assay, all liver enzyme fractions of PCB pretreated rats (S9PCB) showed an increase of the toxification of the pregenotoxicants B[a]P and 2-AA in comparison to enzyme factions of untreated animals (S9(0)). With regard to the reactivity pattern it may be supposed that the PCB mixture probably induced cytochrome P450-dependent oxigenases of the subclasses CYP1A1 and CYP1A2. Additionally, it seems to be of interest that the use of S9(0) fractions did not lead to any or only to weak toxification of B[a]P and 2-AA. Thus, a synergism of cogenotoxicants and pregenotoxicants could be confirmed. PCB could be identified in fatty tissues of children in amounts up to 1 mg/kg. Additionally, pregenotoxicants like polycyclic aromates, mycotoxins and/or aminocontaining compounds, are available in almost all environmental sources. Therefore, from the present point of view, a genetic risk caused by PCB in humans (children) cannot be excluded.


Asunto(s)
Tejido Adiposo/química , Pruebas de Mutagenicidad , Bifenilos Policlorados/toxicidad , Animales , Niño , Sinergismo Farmacológico , Inducción Enzimática/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Bifenilos Policlorados/análisis , Ratas , Ratas Sprague-Dawley , Respuesta SOS en Genética/efectos de los fármacos
12.
Toxicol Lett ; 85(3): 151-6, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8644127

RESUMEN

Five nitro musk compounds widely used in cosmetics and detergents were examined for DNA-damaging and mutation-inducing properties. For this purpose two short-time assays were used, the SOS chromotest and the Salmonella/mammalian microsome test. Musk ambrette showed mutagenicity in Salmonella typhimurium TA 100 requiring metabolic activation by rat liver postmitochondrial supernatant (S9) but it lacked mutagenicity in the absence of S9 and genotoxicity in the SOS chromotest. Musk xylene, musk ketone, musk moskene and musk tibetene showed neither mutagenicity nor genotoxicity in the presence and absence of S9.


Asunto(s)
Daño del ADN , Dinitrobencenos/toxicidad , Mutágenos/toxicidad , Fosfatasa Alcalina/metabolismo , Animales , Arocloros/toxicidad , Biotransformación , Carcinógenos/toxicidad , Relación Dosis-Respuesta a Droga , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Indanos/toxicidad , Mitocondrias Hepáticas/metabolismo , Pruebas de Mutagenicidad , Mutación/efectos de los fármacos , Mutación/genética , Perfumes , Ratas , Respuesta SOS en Genética/efectos de los fármacos , Respuesta SOS en Genética/genética , Salmonella typhimurium/efectos de los fármacos , Relación Estructura-Actividad , Contaminantes Químicos del Agua/toxicidad , Xilenos/toxicidad , beta-Galactosidasa/metabolismo
13.
Zentralbl Hyg Umweltmed ; 198(5): 429-42, 1996 May.
Artículo en Alemán | MEDLINE | ID: mdl-9409899

RESUMEN

In the present study a new in vivo/in vitro animal model was used to study the ability and potency of musk ketone and musk xylene to induce liver specific oxygenases (in vivo) which are necessary of toxify different premutagens, pregenotoxicants and/or precarcinogens to the ultimate DNA damaging agents. Therefore, rats were pretreated with 10, 20 and 40 mg/d nitro musk (NMV) for 5 days by intraperitoneal (i.p.) injection. Then the postmitochondrial fractions of the hepatocytes (S9M) were used to examine the metabolic potency for toxification of the pregenotoxicants benzo[a]pyrene (B[a]P) and 2-aminoanthracene (2-AA) using the SOS chromotest (in vitro). Furthermore, musk xylene, musk ketone, musk ambrette, musk moskene and musk tibetene were examined for their mutagenicity in the Salmonella/microsome assay using S. typhimurium TA97, TA98, TA100 and TA102 and for their genotoxicity in the SOS chromotest using Escherichia coli PQ37 (sfiA::lacZ) in the presence and absence of an exogenous metabolizing system (S9 of PCB induced rats = S9A). Both musk ketone and musk xylene were identified als inducers of toxifying enzymes (oxygenases) in rat liver. Using the in vivo/in vitro model these isoenzyme inductions led to a metabolisation (toxification) of the pregenotoxicants benzo[a]pyrene (B[a]P) and/or 2-aminoanthracene (2-AA) (cogenotoxicity). Using S9M fractions of rats which were i.p.-pretreated with 5 x 40 mg musk ketone the induction factor in the SOS chromotest was IFmax = 4.0 by using 1 nmole B[a]P and IFmax > 4.0 by using 20 nmole 2-AA. Thus, musk ketone seems to be a Cytochrome P450 1A1 and 1A2 isoenzyme inducer in mammals. On the other hand the S9M fractions of musk xylene pretreated rats showed only a toxification of 2-AA (IFmax = 3.0). Therefore, a synergistic effect of enzyme inducers, i.e. musk xylene and musk ketone, and pregenotoxicants, i.e. B[a]P and 2-AA, regarding DNS damaging effects was identified. Musk ambrette showed high mutagenicity in S. typhimurium TA100 (500 His(-)-revertants per mumole, +S9A). Unexpectedly, these DNA damaging effects were not caused by bacterial nitroreductases but by rat S9A metabolisation (!). SOS inducing DNA damages in E. coli PQ37 were not produced (IFmax < 1.5). On the basis of the results presented and under consideration of the concentrations of NMV, other cogenotoxicants and pregenotoxicants such as B[a]P and 2-AA in environmental samples and human tissues, a genotoxic risk for humans has to be assumed.


Asunto(s)
Carcinógenos Ambientales/toxicidad , Ácidos Grasos Monoinsaturados/toxicidad , Pruebas de Mutagenicidad , Nitrocompuestos/toxicidad , Animales , Técnicas de Cultivo , Daño del ADN , Relación Dosis-Respuesta a Droga , Inducción Enzimática/efectos de los fármacos , Humanos , Hígado/enzimología , Masculino , Oxidorreductasas/metabolismo , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
14.
Ophthalmology ; 99(4): 498-502, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1584566

RESUMEN

Enucleated human eyes were banded with metal and silicone bands to produce reductions in their diameter of 2 mm and 4 mm. The ocular rigidity produced by each banding material at each diameter was measured in the pressure range of 10 mmHg to 40 mmHg. Metal bands produced mild reductions in ocular rigidity that were significantly (P less than 0.05 to 0.01) lower than the control ocular rigidities in some pressure ranges. Silicone bands produced large reductions in ocular rigidity that were significantly (P less than 0.01) lower than ocular rigidities observed in metal-banded or control conditions in all pressure ranges. The influence of the elastic silicone banding material on ocular rigidity was greater than the influence of altered shape and wall stress that occurred with metal banding.


Asunto(s)
Fenómenos Fisiológicos Oculares , Curvatura de la Esclerótica , Anciano , Anciano de 80 o más Años , Elasticidad , Humanos , Presión Intraocular/fisiología , Metales , Elastómeros de Silicona
15.
Am J Ophthalmol ; 111(1): 59-64, 1991 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-1985492

RESUMEN

We studied the intraocular pressure changes produced in five eye bank eyes by Perkins, Tono-Pen, and Schiötz tonometry performed by experienced and inexperienced personnel. When all users were considered together, Perkins tonometry produced a mean intraocular pressure increase of 0.7 mm Hg, significantly less than the mean increase of 12.1 mm Hg produced by Tono-Pen tonometry (P less than .05) or the mean increase of 16.5 mm Hg produced by Schiötz tonometry (P less than .01). There was no statistically significant difference between the intraocular pressure increase produced by Tono-Pen or Schiötz tonometry. Tonometry performed by inexperienced Tono-Pen users and experienced or inexperienced Schiötz users produced a significantly greater increase in intraocular pressure than that performed by experienced Tono-Pen users (P less than .05), and an extremely significant increase compared to tonometry performed by experienced or inexperienced Perkins users (P less than .01). The marked increase in intraocular pressure produced by Tono-Pen tonometry suggests that hand-held electronic applanation tonometers should be used with caution in eyes with a weakened cornea or sclera.


Asunto(s)
Presión Intraocular , Tonometría Ocular/efectos adversos , Humanos
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