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1.
Proc Natl Acad Sci U S A ; 106(23): 9191-6, 2009 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-19458258

RESUMEN

The amyloid-beta peptide (Abeta) can generate cytotoxic oligomers, and their accumulation is thought to underlie the neuropathologic changes found in Alzheimer's disease. Known inhibitors of Abeta polymerization bind to undefined structures and can work as nonspecific aggregators, and inhibitors that target conformations that also occur in larger Abeta assemblies may even increase oligomer-derived toxicity. Here we report on an alternative approach whereby ligands are designed to bind and stabilize the 13-26 region of Abeta in an alpha-helical conformation, inspired by the postulated Abeta native structure. This is achieved with 2 different classes of compounds that also reduce Abeta toxicity to cells in culture and to hippocampal slice preparations, and that do not show any nonspecific aggregatory properties. In addition, when these inhibitors are administered to Drosophila melanogaster expressing human Abeta(1-42) in the central nervous system, a prolonged lifespan, increased locomotor activity, and reduced neurodegeneration is observed. We conclude that stabilization of the central Abeta alpha-helix counteracts polymerization into toxic assemblies and provides a strategy for development of specific inhibitors of Abeta polymerization.


Asunto(s)
Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/química , Amiloide/metabolismo , Fragmentos de Péptidos/antagonistas & inhibidores , Fragmentos de Péptidos/química , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/metabolismo , Animales , Animales Modificados Genéticamente , Drosophila melanogaster , Humanos , Modelos Moleculares , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Estructura Secundaria de Proteína
2.
Br J Cancer ; 105(2): 246-54, 2011 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-21712828

RESUMEN

BACKGROUND: The epidermal growth factor receptor-targeted monoclonal antibody cetuximab (Erbitux) was recently introduced for the treatment of metastatic colorectal cancer. Treatment response is dependent on Kirsten-Ras (K-Ras) mutation status, in which the majority of patients with tumour-specific K-Ras mutations fail to respond to treatment. Mutations in the oncogenes B-Raf and PIK3CA (phosphoinositide-3-kinase) may also influence cetuximab response, highlighting the need for a sensitive, accurate and quantitative assessment of tumour mutation burden. METHODS: Mutations in K-Ras, B-Raf and PIK3CA were identified by both dideoxy and quantitative pyrosequencing-based methods in a cohort of unselected colorectal tumours (n=102), and pyrosequencing-based mutation calls correlated with various clinico-pathological parameters. RESULTS: The use of quantitative pyrosequencing-based methods allowed us to report a 13.7% increase in mutation burden, and to identify low-frequency (<30% mutation burden) mutations not routinely detected by dideoxy sequencing. K-Ras and B-Raf mutations were mutually exclusive and independently associated with a more advanced tumour phenotype. CONCLUSION: Pyrosequencing-based methods facilitate the identification of low-frequency tumour mutations and allow more accurate assessment of tumour mutation burden. Quantitative assessment of mutation burden may permit a more detailed evaluation of the role of specific tumour mutations in the pathogenesis and progression of colorectal cancer and may improve future patient selection for targeted drug therapies.


Asunto(s)
Carcinoma/genética , Neoplasias Colorrectales/genética , Análisis Mutacional de ADN/métodos , Individualidad , Mutación , Oncogenes/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/patología , Carcinoma/cirugía , Estudios de Cohortes , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Mutación/fisiología , Análisis de Secuencia de ADN/métodos
3.
J Exp Med ; 129(5): 849-69, 1969 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-5778787

RESUMEN

A combined morphological and metabolic study has been made of the lymphoid cells in the blood during the immune response in man. Similar changes were observed in both primary and secondary responses to a number of different microbial antigens. The cellular response involved an increase in numbers of three types of cell; hyperbasophilic medium lymphocytes, plasma cells, and large lymphoid cells. The large lymphoid cells were about 20 micro in diameter with large nuclei, prominent nucleoli, and an intensely basophilic cytoplasm with numerous polyribosomes. About 30% of these cells were in the DNA synthetic phase of cell growth. Electron microscopy has shown that many of the basophilic medium-sized cells have sufficient well-organized endoplasmic reticulum to be included in the plasma cell series. The hyperbasophilic cells labeled more heavily with tritiated uridine and tritiated leucine than the normal small and medium lymphocytes from the peripheral blood of patients not under antigenic stimulation. The evidence in this paper supports the argument that the atypical mononuclear cells first described by Türk and others in the blood of patients with infections are immunoblasts, plasma cells, and other reactive lymphoid cells representing a circulating population of lymphoid cells derived from lymphoid tissue responding to antigenic stimulation. The presence of such cells may be a valuable indication that an immunological reaction is in progress when direct proof is lacking.


Asunto(s)
Formación de Anticuerpos , Reacciones Antígeno-Anticuerpo , Tolerancia Inmunológica , Linfocitos/inmunología , Células Plasmáticas/inmunología , Autorradiografía , Carcinoma/inmunología , ADN/biosíntesis , Retículo Endoplásmico , Enfermedad de Hodgkin/inmunología , Humanos , Linfocitos/citología , Linfocitos/metabolismo , Melanoma/inmunología , Métodos , Microscopía Electrónica , Neoplasias Gástricas/inmunología , Timidina , Factores de Tiempo , Tritio
4.
Mol Cell Biol ; 14(8): 5229-41, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8035802

RESUMEN

CPF1 is an abundant basic-helix-loop-helix-ZIP protein that binds to the CDEI motif in Saccharomyces cerevisiae centromeres and in the promoters of numerous genes, including those encoding enzymes of the methionine biosynthetic pathway. Strains lacking CPF1 are methionine auxotrophs, and it has been proposed that CPF1 might positively influence transcription at the MET25 and MET16 genes by modulating promoter chromatin structure. We test this hypothesis and show that the regions surrounding the CDEI motifs in the MET25 and MET16 promoters are maintained in a nucleosome-free state and that this requires the entire CPF1 protein. However, the chromatin structure around the CDEI motifs does not change on derepression of transcription and does not correlate with the methionine phenotype of the cell. An intact CDEI motif but not CPF1 is required for transcriptional activation from a region of the MET25 upstream activation sequence. Our results suggest that CPF1 functions to modulate chromatin structure around the CDEI motif but that these changes at the MET25 and MET16 promoters do not explain how CPF1 functions to maintain methionine-independent growth. The presence of CPF1-dependent chromatin structures at these promoters leads to a weak repression of transcription.


Asunto(s)
Centrómero/ultraestructura , Cromatina/ultraestructura , Proteínas de Unión al ADN/fisiología , Proteínas Fúngicas/fisiología , Regiones Promotoras Genéticas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/ultraestructura , Secuencia de Aminoácidos , Secuencia de Bases , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Secuencias Hélice-Asa-Hélice , Leucina Zippers , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos/química , ARN Mensajero/genética , Saccharomyces cerevisiae/genética , Transcripción Genética
5.
J Med Entomol ; 44(4): 568-74, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17695009

RESUMEN

Life histories of "wild" house dust mites, Dermatophagoides pteronyssinus (Trouessart) (Acari: Pyroglyphidae), were compared with laboratory cultures by using a diet consisting of skin and dust or a laboratory diet consisting of dried liver and yeast. Under constant conditions of 25 degrees C and 75% RH, fecundity and rate of reproduction were higher in laboratory cultures on both diets compared with wild mites. There were also trends for a shorter prereproductive period and more rapid egg development of laboratory mites compared with wild mites. Overall, there was little effect of diet on either strain of mites at 75% RH. At low RH (64%), fecundity was significantly lower (for both strains on both diets), and there were also trends for longer prereproductive period, reduced rate of reproduction, reduced adult survival, prolonged egg and juvenile development, or a combination compared with 75% RH. Additionally egg and juvenile mortality were significantly higher on the liver and yeast diet. Overall, the skin and dust diet favored both strains of mites at 64% RH. On the liver and yeast diet at 64% RH, wild mite adults performed significantly better than laboratory mites, and egg mortality was lower. These results suggest that laboratory mites have stronger reproduction and development than wild mites, except when under environmental stress and that diet is a significant factor, particularly in suboptimal conditions. This could have important implications for predictive models of house dust mite populations in their natural habitat. Ideally, such models should be developed using data from wild dust mite populations reared on a natural diet.


Asunto(s)
Polvo , Ecosistema , Pyroglyphidae/fisiología , Animales , Dieta , Femenino , Esperanza de Vida , Masculino , Oviposición , Pyroglyphidae/crecimiento & desarrollo , Reproducción , Piel/parasitología
6.
Cancer Res ; 54(15): 4072-6, 1994 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8033139

RESUMEN

There is increasing experimental evidence to indicate that O6-methyldeoxyguanosine (O6-MedG) formation in DNA is a critical cytotoxic event following exposure to certain antitumor alkylating agents and that the DNA repair protein O6-alkylguanine-DNA-alkyltransferase (ATase) can confer resistance to these agents. We recently demonstrated a wide interindividual variation in the depletion and subsequent regeneration of ATase in peripheral blood lymphocytes of patients treated with 24-h continuous infusion of 1-p-carboxyl-3,3-dimethylphenyltriazene (CB10-277) for metastatic melanoma. We have now measured the formation of O6-MedG in the DNA of peripheral leukocytes of nine patients receiving this treatment regimen. This lesion could be detected in DNA within 1 h and a progressive increase in adduct levels occurred during the CB10-277 infusion and for 24 h after completion. Considerable interindividual variation was observed in the peak O6-MedG levels, with values ranging from 3.0 to 23.8 mumol O6-MedG/mol deoxyguanosine (mean, 12.3 +/- 6.4 mumol O6-MedG/mol deoxyguanosine) following the first treatment cycle, possibly as a consequence of differences in the capacity of patients to metabolize CB10-277 to a methylating agent. There was, nevertheless, a clear temporal relationship between the progressive formation of leukocyte O6-MedG and lymphocyte ATase depletion. Repeated-measures regression showed that this was statistically significant (P < 0.001) during the CB10-277 infusion. A significant inverse correlation was also seen between pretreatment lymphocyte ATase activity and peak O6-MedG levels in leukocyte DNA (r = -0.73) and the area under the leukocyte O6-MedG concentration-time curve (r = -0.76). Metabolism of CB10-277 to a methylating agent could be one factor that combines with DNA repair capacity to determine clinical response, because the two responses observed in this series occurred in the two patients with the highest leukocyte O6-MedG levels and also the lowest pretreatment ATase activity. Hematological toxicity developed in the same two patients.


Asunto(s)
Antineoplásicos/metabolismo , ADN Nucleotidiltransferasas/metabolismo , ADN de Neoplasias/metabolismo , Desoxiguanosina/análogos & derivados , Guanina/análogos & derivados , Leucocitos/metabolismo , Melanoma/metabolismo , Triazenos/metabolismo , Adulto , Anciano , Antineoplásicos/uso terapéutico , Desoxiguanosina/biosíntesis , Femenino , Guanina/metabolismo , Humanos , Linfocitos/enzimología , Masculino , Melanoma/sangre , Persona de Mediana Edad , Triazenos/uso terapéutico
7.
Cancer Res ; 54(5): 1298-304, 1994 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-8118819

RESUMEN

The entire coding sequence of the p53 gene was analysed for the presence of mutations in 12 families conforming to a restricted definition of Li-Fraumeni syndrome (classic LFS) and nine families with features of LFS conforming to a broader definition. Mutations were detected in seven families. Six were point mutations with one each affecting codons 175, 180, and 220 and three affecting codon 248. The seventh was a deletion/insertion mutation in exon 4. Germline mutations in p53 were a feature of families which included children with rhabdomyosarcoma and/or adrenal cortical carcinoma. Germline p53 mutations were detected in six of the nine families with such tumors. An analysis of these 7 mutations, together with 34 published examples, showed that more than one-half were transitions at CpG dinucleotides, suggesting that the majority of germline p53 mutations may arise as a result of spontaneous events. The most common cancers occurring in the 41 families with germline p53 mutations, in common with classic LFS, were bone and soft tissue sarcoma, breast cancer, brain tumors, leukemia, and adrenocortical carcinoma, although less than one-half of the probands with germline p53 mutations came from classic LFS families. More than one-half of the cancers overall and nearly one-third of the breast cancers were diagnosed before 30 years of age. These observations have important implications for asymptomatic carriers of germline p53 mutations, and there is a need for international collaboration in the development of protocols for the management of such families.


Asunto(s)
Genes p53/genética , Síndrome de Li-Fraumeni/genética , Mutación/genética , Secuencia de Bases , Niño , Codón/genética , Exones/genética , Salud de la Familia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Linaje , Prevalencia
8.
Biochim Biophys Acta ; 636(2): 234-43, 1981 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7284351

RESUMEN

The sites of action, in spinach thylakoid, of known inhibitors of electron transport at the reducing end of photosystem I have been more accurately located by parallel investigation of effects on three partial reactions: photo-reduction (from water) of added NADP+, photoreduction of added cytochrome c, and dark reduction of cyto-chrome c by added NADPH. Comparison with inhibitory effects on cyclic electron flow (registered by the slow phase of the electrochromic response during repetitive flash excitation) permitted assessment of the role of ferredoxin and ferredoxin-NADP+ reductase (ferredoxin: NADP+ oxidoreductase, EC 1.18.1.3) in the cyclic electron transport pathway around photosystem I. Disulfodisalicylidenepropane-1,1-diamine inhibited all the above partial reactions except the ferredoxin-dependent photoreduction of cytochrome C. thereby indicating its interference with the reductase or the complexation between reductase and ferredoxin. Studies with purified ferredoxin-NADP+ reductase established it as the sensitive component. Cyclic flow is also sensitive to the above inhibitor and thus presumably involves the reductase. Supporting evidence for this came from studies of inhibition by substituted maleimides, which are inhibitors of electron transfer through the isolated reductase; these also inhibited the slow phase of the electrochromic response and all partial reactions except the photoreduction of cytochrome c. In contrast, an antiserum against the reductase affected only reactions involving NADP. The conclusion is drawn that the pathway of cyclic electron transport includes both ferredoxin and ferredoxin-NADP+ reductase, but not the NADP-binding site on the reductase.


Asunto(s)
Cloroplastos/enzimología , Ferredoxina-NADP Reductasa/antagonistas & inhibidores , NADH NADPH Oxidorreductasas/antagonistas & inhibidores , Fotosíntesis , Cloroplastos/efectos de los fármacos , Transporte de Electrón , Ferredoxina-NADP Reductasa/inmunología , Ferredoxinas/metabolismo , Sueros Inmunes/farmacología , Maleimidas/farmacología , Compuestos de Tosilo
9.
Biochim Biophys Acta ; 592(3): 495-505, 1980 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-6774748

RESUMEN

Evolution of oxygen and turnover of cytochromes b-563 and f were measured upon illumination of isolated intact spinach chloroplasts with a series of flashes. The flash yield of cytochrome f oxidation approximated the sum of the yields of cytochrome b-563 reduction and electron transfer through Photosystem II, regardless of whether HCO(-3), 3-phosphoglycerate or O2 served as the terminal electron acceptor. No absorbance contribution form cytochrome b-559 was discerned within the time range studied. Some pseudocyclic electron flow occurred when both HCO(-3) and 3-phosphoglycerate were omitted, and possibly also during induction of photosynthesis; however, the flash yield data suggest tht O2 is not reduced at a significant rate during steady state photosynthesis. The maximum rate of cytochrome f turnover (1000 microequiv./mg chlorophyll per h) was adequate to support the highest rates of photosynthesis observed in isolated chloroplasts. These results agree with the concept that cytochrome f is a component both of the linear and cyclic pathways whereas cytochrome b-563 functions only in the cyclic pathway. NH4Cl decreased the half time of cytochrome b-563 oxidation fro 11.6 to 8.2 ms and decreased the half time of cytochrome f reduction from 7.2 to 2.8 ms. The cyclic and linear pathways thus seem to be jointly regulated by a transthylakoid H+ gradient through a common control point on the reducing side of cytochrome f. Cyclic turnover also increased during the induction phase of photosynthesis, when linear throughput is limited by the rate of utilization of NADPH. The slow rise in the P-518 transient correlated with increased cyclic activity under the above conditions. It is proposed that flexibility in the utilization of linear and cyclic pathways allows the chloroplast to generate ATP and NADPH in ratios appropriate to varying needs.


Asunto(s)
Dióxido de Carbono/metabolismo , Cloroplastos/metabolismo , Grupo Citocromo b , Citocromos/metabolismo , Plantas/metabolismo , Citocromos f , Transporte de Electrón/efectos de la radiación , Ácidos Glicéricos/metabolismo , Luz , Compuestos Organofosforados/metabolismo , Oxidación-Reducción , Oxígeno/metabolismo , Fotosíntesis
10.
Biochim Biophys Acta ; 547(1): 138-48, 1979 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-465483

RESUMEN

Flash excitation of isolated intact chloroplasts promoted absorbance transients corresponding to the electrochromic effect (P-518) and the alpha-bands of cytochrome b6 and cytochrome f. Under conditions supporting coupled cyclic electron flow, the oxidation of cytochrome b6 and the reduction of cytochrome f had relaxation half-times of 15 and 17 ms, respectively. Optimal poising of cyclic electron flow, achieved by addition of 0.1 microM 3-(3,4-dichlorophenyl)-1,1-dimethylurea, increased phosphorylation of endogenous ADP and prolonged these relaxation times. The presence of NH4Cl, or monensin plus NaCl, decreased the half-times for cytochrome relaxation to approximately 2 ms. Uncouplers also revealed the presence of a slow rise component in the electrochromic absorption shift with formation half-time of about 2 ms. Ths inhibitors of cyclic phosphorylation antimycin and 2,5-dibromo-3-methyl-6-isoprophy-p-benzoquinone abolished the slow rise in the electrochromic shift and prolonged the uncoupled relaxation times of cytochromes b6 and f by factors of ten or more. These observations indicate that cytochrome b6, plastoquinone and cytochrome f participated in a coupled electron transport process responsible for cyclic phosphorylation in intact chloroplasts. Estimations of cyclic phosphorylation rates from 40 to 120 mumol ATP/mg chlorophyll per h suggest that this process can provide a substantial fraction of the ATP needed for CO2 fixation.


Asunto(s)
Cloroplastos/metabolismo , Antimicina A/farmacología , Cloroplastos/efectos de los fármacos , Citocromos/metabolismo , Oscuridad , Diurona/farmacología , Transporte de Electrón , Cinética , Luz , Fotofosforilación/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Plantas , Espectrofotometría
11.
Biochim Biophys Acta ; 547(1): 127-37, 1979 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37900

RESUMEN

Addition of NADPH to osmotically lysed spinach chloroplasts results in a reduction of the primary acceptor (Q) of photosystem II. This reduction of Q reaches a maximum of 50% in chloroplasts maintained under weak illumination and requires added ferredoxin and Mg2+. The reaction is inhibited by (I) an antibody to ferredoxin-NADP+ reductases (EC 1.6.7.1), (ii) treatment of chloroplasts with N-ethylmaleimide in the presence of NADPH, (iii) disulfodisalicylidenepropanediamine, (iv) antimycin, and (v) acceptors of non-cyclic electron transport. Uncouplers of phosphorylation do not affect NADPH-driven reduction of Q. It is proposed that electron flow from NADPH to Q may occur in the dark by a pathway utilising portions of the normal cyclic and non-cyclic electron carrier sequences. The possible in vivo role for such a pathway in redox poising of cyclic electron transport and hence in controlling the ATP/NADPH supply ratio is discussed.


Asunto(s)
Cloroplastos/metabolismo , NADP/metabolismo , Fotosíntesis , Cloroplastos/efectos de los fármacos , Oscuridad , Ditiotreitol/farmacología , Transporte de Electrón , Ferredoxina-NADP Reductasa/metabolismo , Ferredoxinas/metabolismo , Cinética , Magnesio/farmacología , Oxidación-Reducción , Fotosíntesis/efectos de los fármacos , Plantas , Espectrometría de Fluorescencia
12.
Biochim Biophys Acta ; 1502(1): 85-94, 2000 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-10899434

RESUMEN

The association of inheritance of different apolipoprotein E (APOE, gene; apoE, protein) alleles with the risk and rate of onset of Alzheimer's disease (AD) is now well established and widely confirmed. While there are now a collection of hypotheses concerning the specific relationship of APOE polymorphisms to various phenotypic manifestations of AD, no single compelling theory has been tested and universally accepted. The only clear fact emerging during the past 6 years is that differences in APOE genotype affect the average rate of disease onset as a predictable function of the inheritance of this polymorphic gene. Methods now exist to enable experimental designs to study the metabolic effects of inheriting different APOE alleles, addressing what differences that may be present for many years, perhaps over the entire lifetime, can lead to earlier or later manifestations of the disease and are therapeutically tractable. This review summarizes part of an experimental approach to identify biological pathways influenced by the different APOE polymorphisms that are relevant to the pathogenesis of AD.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Apolipoproteínas E/metabolismo , Alelos , Enfermedad de Alzheimer/genética , Animales , Apolipoproteína E3 , Apolipoproteína E4 , Apolipoproteínas E/genética , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Marcación de Gen , Técnicas Genéticas , Genotipo , Humanos , Polimorfismo Genético , ARN Mensajero/metabolismo
13.
J Clin Oncol ; 7(9): 1303-9, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2769329

RESUMEN

A clinical comparison of the nodular and diffuse variants of lymphocyte-predominant Hodgkin's disease (HD-LP) has shown them to be similar in all respects, including survival and relapse-free survival (RFS). In addition, they appear similar to mixed cellularity (MC) and nodular sclerosing Hodgkin's disease (HD-NS) with regard to clinical course. Thus, the reported phenotypic differences between nodular lymphocyte predominant Hodgkin's disease (HD-LP[N]) and other forms of the disease do not appear to be reflected in clinical behavior.


Asunto(s)
Enfermedad de Hodgkin/patología , Ganglios Linfáticos/patología , Linfocitos/patología , Adulto , Anciano , Femenino , Enfermedad de Hodgkin/tratamiento farmacológico , Enfermedad de Hodgkin/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Estadística como Asunto
14.
J Clin Oncol ; 6(6): 940-6, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3373265

RESUMEN

The chest radiographs (CXRs) of 110 patients with mediastinal Hodgkin's disease (HD) were reviewed to determine the incidence, degree, and significance of mediastinal abnormalities following treatment. Residual mediastinal abnormalities were defined as either minimal or measurable, and occurred in 64% of all patients at the completion of treatment, but were more common in those with bulky mediastinal disease at presentation (40 of 48, 83%). Fifty-one patients with a mediastinal abnormality at the end of treatment had follow-up films available. Partial or complete regression of the abnormality occurred by 1 year in 30 of these patients (59%). Over a median follow-up of 80.5 months, there were more relapses (13 of 70, 19%) in patients with residual abnormalities following treatment than in those where the mediastinum was considered normal (four of 40, 10%). Measurable abnormality was associated with a higher relapse rate (six of 25, 24%) than minimal abnormality (seven of 45, 16%), but none of these differences were statistically significant. the subsequent relapse rate for patients with persisting abnormality at 1 year was 14%, compared with 17% for patients in whom regression had occurred and 14% in whom the mediastinum had always been considered normal. Considering the whole group, the presence of a mediastinal abnormality following treatment did not predict for relapse, but for the 34 patients treated by chemotherapy (CTR) alone, a residual abnormality was associated with a significantly higher relapse rate (P = .029). We conclude that following mediastinal radiotherapy (XRT) administered either alone or combined with CTR, residual mediastinal abnormalities do not indicate the need for further treatment. However, following CTR alone, such abnormalities may signify persisting disease and we recommend that XRT be considered for these patients.


Asunto(s)
Enfermedad de Hodgkin/diagnóstico por imagen , Neoplasias del Mediastino/diagnóstico por imagen , Mediastino/diagnóstico por imagen , Adolescente , Adulto , Terapia Combinada , Femenino , Enfermedad de Hodgkin/mortalidad , Enfermedad de Hodgkin/terapia , Humanos , Masculino , Neoplasias del Mediastino/mortalidad , Neoplasias del Mediastino/terapia , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Pronóstico , Radiografía Torácica
15.
J Clin Oncol ; 13(1): 134-9, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7799013

RESUMEN

PURPOSE AND METHODS: Gonadal function was assessed in 89 patients after chemotherapy for Hodgkin's disease (HD). Thirty-seven patients had received mechlorethamine, vinblastine, prednisolone, and procarbazine (MVPP) and 52 patients, a hybrid combination of chlorambucil, vinblastine, prednisolone, procarbazine, doxorubicin, vincristine, and etoposide (ChIVPP/EVA). Fifty men (MVPP, n = 21; ChIVPP/EVA, n = 29) with a median age of 26 years (range, 16 to 54) and 39 women (MVPP, n = 16; ChIVPP/EVA, n = 23) with a median age of 30 years (range, 15 to 47) were studied at a median of 30 months (range, 4 to 83) following chemotherapy. RESULTS: Semen analysis showed azoospermia in 35 of 37 men, and increased serum follicle-stimulating hormone (FSH) levels in this group confirmed severe germinal epithelial damage. Analysis of pretreatment semen in 28 men showed azoospermia in one, oligospermia in four (sperm count < 20 x 10(6)/mL), and a normal sperm count in the remaining 23. In the women, 26 of 34 (76%) with a regular menstrual cycle before commencing chemotherapy became amenorrheic following treatment. Menses returned in 10 women, who had a median age of 25 years (range, 21 to 34), and there were two pregnancies in this group. In the other 16, with a median age of 36 years (range, 27 to 47), amenorrhea persisted and premature ovarian failure was confirmed by increased serum gonadotrophins and reduced estradiol (E2) concentrations. Of the original eight women in whom menses were maintained following treatment, two subsequently developed amenorrhea and the clinical and biochemical features of an early menopause. In total, 18 of 34 women (53%) required hormone replacement therapy for chemotherapy-induced ovarian failure. CONCLUSION: There was no statistically significant difference in the frequency or severity of gonadal dysfunction between MVPP- and ChIVPP/EVA-treated patients. We conclude that both of these chemotherapy schedules cause substantial damage to gonadal function in both sexes.


Asunto(s)
Amenorrea/inducido químicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Enfermedad de Hodgkin/tratamiento farmacológico , Libido/efectos de los fármacos , Semen/efectos de los fármacos , Adolescente , Adulto , Clorambucilo/efectos adversos , Doxorrubicina/efectos adversos , Etopósido/efectos adversos , Femenino , Hormona Folículo Estimulante/sangre , Enfermedad de Hodgkin/sangre , Humanos , Hormona Luteinizante/sangre , Masculino , Mecloretamina/efectos adversos , Ciclo Menstrual/efectos de los fármacos , Persona de Mediana Edad , Prednisolona/efectos adversos , Insuficiencia Ovárica Primaria/inducido químicamente , Procarbazina/efectos adversos , Estudios Prospectivos , Globulina de Unión a Hormona Sexual/análisis , Recuento de Espermatozoides/efectos de los fármacos , Testículo/efectos de los fármacos , Testículo/patología , Testosterona/sangre , Vinblastina/efectos adversos , Vincristina/efectos adversos
16.
J Clin Oncol ; 2(8): 892-7, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6379122

RESUMEN

This paper reports the five-year follow-up (range, 1-8 years) of 56 patients with pathologic stage IIIA Hodgkin's disease randomized for chemotherapy alone or chemotherapy followed by radiotherapy to previous areas of disease (26 treated with mustine, vinblastine, procarbazine, and prednisolone [MVPP] alone, 30 with MVPP and radiotherapy). Of the 56 patients 53 (95%) achieved a complete remission with chemotherapy and of these only five (9%) have relapsed; three died of Hodgkin's disease. There was no improvement in relapse-free survival associated with the uses of radiotherapy following chemotherapy but in view of the small numbers of relapses and the excellent results following chemotherapy alone, a significant improvement could not be expected. The use of MVPP alone can be recommended as an alternative therapy for patients with stage IIIA Hodgkin's disease. This avoids both the physical and psychologic morbidity associated with the high relapse rate following extensive primary radiotherapy and the necessity of combined modality treatment for about half these patients. The question of whether radiotherapy should be given to areas of previous bulk following chemotherapy has not yet been answered in this trial which is continuing.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Hodgkin/tratamiento farmacológico , Adulto , Ensayos Clínicos como Asunto , Terapia Combinada , Femenino , Enfermedad de Hodgkin/mortalidad , Enfermedad de Hodgkin/patología , Enfermedad de Hodgkin/radioterapia , Humanos , Masculino , Mecloretamina/administración & dosificación , Estadificación de Neoplasias , Prednisolona/administración & dosificación , Procarbazina/administración & dosificación , Distribución Aleatoria , Recurrencia , Vinblastina/administración & dosificación
17.
J Clin Oncol ; 13(9): 2379-85, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7666097

RESUMEN

PURPOSE AND METHODS: Between December 1984 and August 1992, 423 patients with newly diagnosed Hodgkin's disease (HD) were entered onto a randomized clinical trial that compared the regimen of mechlorethamine, vinblastine, procarbazine, and prednisone (MVPP) with a doxorubicin-containing hybrid regimen (chlorambucil, vinblastine, procarbazine, and prednisone/etoposide, vincristine, and doxorubicin [ChlVPP/EVA]). Median age for the group was 29.5 years (range, 15.2 to 68.8), and 52% had bulk disease. RESULTS: After chemotherapy, patients in the hybrid arm of the trial had a higher complete remission (CR) rate (68.1% v 55.3%) and a lower failure rate (2.4% v 12.5%) than those in the MVPP arm. There were also fewer deaths during treatment in the hybrid arm of the trial (five v 13). With a median follow-up period for survivors of 4.5 years (range, 0 to 9), actuarial 5-year progression-free survival (PFS) for all cases is 80% in the hybrid arm and 66% in the MVPP arm (P = .005). A nonsignificant trend toward a better overall survival in the hybrid arm of the trial has also been identified. CONCLUSION: These results suggest that ChlVPP/EVA hybrid is superior to MVPP in the treatment of HD. It has therefore been adopted as standard first-line therapy at the two centers.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Hodgkin/tratamiento farmacológico , Adolescente , Adulto , Anciano , Clorambucilo/administración & dosificación , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Etopósido/administración & dosificación , Femenino , Estudios de Seguimiento , Enfermedad de Hodgkin/mortalidad , Humanos , Masculino , Mecloretamina/administración & dosificación , Persona de Mediana Edad , Prednisolona/administración & dosificación , Procarbazina/administración & dosificación , Inducción de Remisión , Tasa de Supervivencia , Vinblastina/administración & dosificación , Vincristina/administración & dosificación
18.
J Clin Oncol ; 11(1): 15-21, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8418226

RESUMEN

PURPOSE: This study was designed to test the feasibility of administering doxorubicin at an optimal dose-intensity (> 70 mg/m2 per 21 days) in combination with ifosfamide under recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) cover in patients with metastatic soft tissue sarcomas. PATIENTS AND METHODS: One hundred four eligible patients (of 111 entered) in 16 centers received doxorubicin 75 mg/m2 plus ifosfamide 5 g/m2 every 3 weeks for up to seven cycles. rhGM-CSF (250 micrograms/m2) was administered once or twice daily by subcutaneous injections for up to 14 days between cycles of chemotherapy. RESULTS: Full protocol dose-intensity of chemotherapy was administered to the majority of patients with only 15 of 293 cycles being complicated by febrile episodes that required hospitalization. There were two treatment-related deaths: one from septicemia and one from cardiac failure. The main toxicities attributed to rhGM-CSF were pruritus and rash. A 45% response rate (10% complete remission [CR]) was seen, with a median response duration of 9 months and median survival of 15 months. CONCLUSION: This high-dose regimen of chemotherapy was feasible under rhGM-CSF cover and produced a higher response rate and median survival than previously seen by the European Organization for Research and Treatment of Cancer (EORTC) Soft Tissue Sarcoma Group. A randomized phase III study is now underway comparing this regimen with conventional-dose doxorubicin/ifosfamide to test the dose-response relationship.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Enfermedades de la Médula Ósea/prevención & control , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Sarcoma/tratamiento farmacológico , Neoplasias de los Tejidos Blandos/tratamiento farmacológico , Adulto , Anciano , Análisis de Varianza , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Enfermedades de la Médula Ósea/inducido químicamente , Doxorrubicina/administración & dosificación , Esquema de Medicación , Estudios de Factibilidad , Femenino , Humanos , Ifosfamida/administración & dosificación , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Sarcoma/secundario , Análisis de Supervivencia , Resultado del Tratamiento
19.
J Clin Oncol ; 7(11): 1630-6, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2809679

RESUMEN

The Ann Arbor classification for describing the stage of Hodgkin's disease at initial presentation has formed the basis upon which treatment is selected and has allowed comparison of results achieved by different investigators for almost two decades. A meeting was convened to review the classification and modify it in the light of experience gained in its use and new techniques for evaluating disease. It was concluded that the structure of the classification be maintained. It was particularly recommended: (1) that computed tomography (CT) be included as a technique for evaluating intrathoracic and infradiaphragmatic lymph nodes; (2) that the criteria for clinical involvement of the spleen and liver be modified to include evidence of focal defects with two imaging techniques and that abnormalities of liver function be ignored; (3) that the suffix 'X' to designate bulky disease (greater than 10 cm maximum dimension) be introduced; and (4) that a new category of response to therapy, unconfirmed/uncertain complete remission (CR[u]), be introduced to accommodate the difficulty of persistent radiological abnormalities of uncertain significance.


Asunto(s)
Enfermedad de Hodgkin/diagnóstico , Estadificación de Neoplasias , Enfermedad de Hodgkin/clasificación , Enfermedad de Hodgkin/patología , Enfermedad de Hodgkin/terapia , Humanos , Ganglios Linfáticos/patología , Tomografía Computarizada por Rayos X
20.
J Clin Oncol ; 8(12): 2032-9, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2230895

RESUMEN

Between 1976 and 1985, 391 patients (202 premenopausal, 189 postmenopausal) with operable breast cancer and positive axillary lymph nodes were randomized after total mastectomy and axillary clearance to receive cyclophosphamide, methotrexate, and fluorouracil (CMF) (n = 193) or no adjuvant therapy (n = 198). After a median follow-up of 8 years, both relapse-free survival (RFS) and survival (S) were significantly prolonged in premenopausal patients receiving CMF (RFS, P less than .001; S, P = .003). Treatment with CMF resulted in a significant improvement in RFS in premenopausal patients both with steroid receptor-positive and steroid receptor-negative tumors and also in subgroups of premenopausal patients defined by the number of axillary nodes involved. Premenopausal patients who developed permanent amenorrhea following CMF had a significantly better RFS than those who continued to menstruate. Induction of amenorrhea following CMF was related to age, with almost all patients over 40 years becoming amenorrheic. For patients less than or equal to 40 years, development of amenorrhea following CMF did not influence outcome. No difference was detected between control and CMF groups (RFS, P = .9; S, P = .9) in postmenopausal patients nor in any subgroup of these patients. The results of this trial of the efficacy of CMF for improving RFS and S have strengthened with longer follow-up.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Adulto , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Cisplatino/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Mastectomía Radical Modificada , Menopausia , Ciclo Menstrual/efectos de los fármacos , Metotrexato/administración & dosificación , Persona de Mediana Edad , Tasa de Supervivencia
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