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1.
Nat Ecol Evol ; 7(1): 92-101, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36471120

RESUMEN

There have been recent renewed commitments to increase the extent of protected areas to combat the growing biodiversity crisis but the underpinning evidence for their effectiveness is mixed and causal connections are rarely evaluated. We used data gathered by three large-scale citizen science programmes in the UK to provide the most comprehensive assessment to date of whether national (Sites of Special Scientific Interest) and European (Special Protection Areas/Special Areas of Conservation) designated areas are associated with improved state (occurrence, abundance), change (rates of colonization, persistence and trend in abundance), community structure and, uniquely, demography (productivity) on a national avifauna, while controlling for differences in land cover, elevation and climate. We found positive associations with state that suggest these areas are well targeted and that the greatest benefit accrued to the most conservation-dependent species since positive associations with change were largely restricted to rare and declining species and habitat specialists. We suggest that increased productivity provides a plausible demographic mechanism for positive effects of designation.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Animales , Ecosistema , Aves , Reino Unido
2.
Sci Total Environ ; 731: 138851, 2020 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-32408204

RESUMEN

Provision of supplementary food for garden birds is practiced on a large scale in multiple countries. While this resource has benefits for wild bird populations, concern has been expressed regarding the potential for contamination of foodstuffs by mycotoxins, and the implications this might have for wildlife health. We investigated whether aflatoxin (AF) and ochratoxin A (OA) residues are present in foodstuffs sold for wild bird consumption at point of sale in Great Britain using high pressure liquid chromatography analyses. The hypothesis that production of these mycotoxins occurs in British climatic conditions, or under storage conditions after the point of sale, was tested under experimental conditions but was not proved by our study. While the majority of peanut samples were negative for AF residues, 10% (10/98) of samples at point of sale and 11% (13/119) of those across the storage and climate exposure treatment replicates contained AFB1 that exceeded the maximum permitted limit of 20 µg/kg. No significant difference was found in the detection of either mycotoxin between branded and non-branded products. The clinical significance, if any, of exposure of wild birds to mycotoxins requires further investigation. Nevertheless, the precautionary principle should be adopted and best practice steps to reduce the likelihood of wild bird exposure to mycotoxins are recommended.


Asunto(s)
Aflatoxinas/análisis , Micotoxinas/análisis , Animales , Aves , Contaminación de Alimentos/análisis , Ocratoxinas , Reino Unido
3.
J Cell Biol ; 33(1): 1-14, 1967 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6033936

RESUMEN

This paper describes the effect of parathyroid extract on the fine structure of bone cells in the proximal metaphysis of the tibia. The extract was given to rats intraperitoneally, in single or repeated doses of 1-14 units (USP) per gram body weight, over short or extended periods, and the tissue was examined between 6 and 26 hr after the commencement of injection. During this period, osteoblasts showed the greatest changes. Their mitochondria became swollen and contained dense granules; both rough- and smooth-surfaced vesicles were distended; ribosomes were separated from the membranes; and various dense bodies appeared in the cytoplasm. Osteocytes were similarly but less affected, and osteoclasts differed little from those in normal animals. Eventually after repeated injections, the fine structure of many of the cells was disrupted. These changes were accompanied by erosion of the bony trabeculae without any great increase in numbers of osteoclasts. It is possible that the alterations in fine structure were the result of damage to the cells by the parathyroid extract. However, since the extract did not seem to stimulate classical osteoclastic activity, the mitochondrial swelling and dense bodies could have been related to the removal of mineral and matrix, respectively.


Asunto(s)
Osteoblastos/efectos de los fármacos , Hormona Paratiroidea/administración & dosificación , Hormona Paratiroidea/farmacología , Animales , Calcificación Fisiológica , Citoplasma/efectos de los fármacos , Gránulos Citoplasmáticos/efectos de los fármacos , Membranas/efectos de los fármacos , Microscopía , Microscopía Electrónica , Mitocondrias/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Osteocitos/efectos de los fármacos , Ratas , Ribosomas/efectos de los fármacos
4.
Science ; 289(5484): 1554-7, 2000 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10968791

RESUMEN

We simulated the effects of the introduction of genetically modified herbicide-tolerant (GMHT) crops on weed populations and the consequences for seed-eating birds. We predict that weed populations might be reduced to low levels or practically eradicated, depending on the exact form of management. Consequent effects on the local use of fields by birds might be severe, because such reductions represent a major loss of food resources. The regional impacts of GMHT crops are shown to depend on whether the adoption of GMHT crops by farmers covaries with current weed levels.


Asunto(s)
Chenopodiaceae , Productos Agrícolas/genética , Ecosistema , Herbicidas , Modelos Biológicos , Pájaros Cantores , Agricultura , Animales , Chenopodiaceae/genética , Chenopodiaceae/crecimiento & desarrollo , Ingeniería Genética , Matemática , Dinámica Poblacional , Semillas , Reino Unido
5.
Science ; 168(3931): 588-9, 1970 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-4314271

RESUMEN

Bone samples from potentially leukemic and leukemic mice revealed numerous 90-to 110-nanometer particles morphologically identical to murine leukemia virus. Particles were observed budding from plasma membranes of osteocytes and osteoblasts but were most numerous in osteocyte lacunae. Particles were not observed in bone samples from mice which rarely develop leukemia.


Asunto(s)
Huesos/microbiología , Virus de la Leucemia Murina/aislamiento & purificación , Leucemia Linfoide/genética , Animales , Ratones , Microscopía Electrónica
6.
Sci Rep ; 9(1): 19557, 2019 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-31863006

RESUMEN

Estimating and understanding variation in survival rates is crucial for the management of threatened species, especially those with limited population sizes and/or restricted ranges. Using a capture-resighting dataset covering 2004-2017, we estimate adult survival in the Raso lark Alauda razae, a Critically Endangered single-island Cape Verdean endemic, whose population varied 25-fold during the study. Average annual adult survival was similar for males (0.813 ± 0.011) and females (0.826 ± 0.011) over the period. These values are high for a temperate passerine but not unusual for an insular tropical species like the lark. The oldest bird was recorded 13 years after first ringing. There was strong evidence that survival varied among years (between 0.57 and 0.95), being generally higher in wetter years. Survival, especially of males, was lower when the population was large, but only in drier years. Survival declined with age but there was no evidence that this decline was other than linear. High survival, even in the face of dry conditions, at least when the population is depressed, has probably contributed to the persistence of the species on its 7 km2 island home over several centuries.


Asunto(s)
Passeriformes/fisiología , Animales , Especies en Peligro de Extinción , Femenino , Masculino , Densidad de Población , Dinámica Poblacional , Lluvia
7.
J Clin Invest ; 93(2): 516-20, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7906694

RESUMEN

We evaluated the prognostic significance of p185c-erbB-2 expression and ras gene mutations in all patients diagnosed with a pulmonary adenocarcinoma between 1982 and 1985 at the University of Iowa. p185c-erbB-2 expression was detected in 15 cases (34%). A ras gene mutation was found in 16 cases (36%) and all were in codon-12 of K-ras. No N-ras mutations were identified. Both p185c-erbB-2 expression and a K-ras mutation were found only in codon-12 and present in six cases (14%). By univariate analysis p185c-erbB-2 expression was associated with shortened survival (P = 0.02) while the presence of a K-ras mutation was not (P = 0.16). Multivariate analysis by the Cox proportional hazards model, controlling for patient age and tumor stage, also continued to identify p185c-erbB-2 expression as an independent unfavorable prognostic factor (P = 0.01). In this model a K-ras mutation also approached significance as a poor prognostic indicator (P = 0.06). The impact of both p185c-erbB-2 expression and a K-ras mutation on survival was additive and highly significant (P = 0.004). This additive nature suggests that together these two markers identify a high-risk population of lung adenocarcinoma patients that may benefit from aggressive therapy.


Asunto(s)
Adenocarcinoma/genética , Biomarcadores de Tumor/análisis , Receptores ErbB/biosíntesis , Genes ras , Neoplasias Pulmonares/genética , Mutación Puntual , Proteínas Proto-Oncogénicas/biosíntesis , Proto-Oncogenes , Análisis Actuarial , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Factores de Edad , Secuencia de Bases , Cartilla de ADN , ADN de Neoplasias/aislamiento & purificación , ADN de Neoplasias/metabolismo , Receptores ErbB/análisis , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Datos de Secuencia Molecular , Análisis Multivariante , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , Pronóstico , Modelos de Riesgos Proporcionales , Proteínas Proto-Oncogénicas/análisis , Receptor ErbB-2 , Factores de Riesgo , Análisis de Supervivencia , Factores de Tiempo
8.
J Clin Pathol ; 59(7): 711-5, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16467168

RESUMEN

BACKGROUND: The p16 and retinoblastoma (Rb) gene products are part of the retinoblastoma pathway controlling the G1-S transition of the cell cycle. Few studies on the expression of p16 and retinoblastoma proteins in oral cavity squamous carcinomas have been conducted. AIM: To correlate the expression of p16 and retinoblastoma proteins to clinicopathological characteristics in these tumours. METHODS: 45 patients with resected oral cavity squamous carcinoma were selected, for whom this was the initial treatment and who were followed up for 5 years or until death. Immunohistochemical stains with antibodies to the Rb and p16 gene products were carried out on paraffin wax-embedded tissue. Data on clinicopathological features such as tumour differentiation, nodal status, stage and survival outcome were collected. RESULTS: Retinoblastoma expression was seen in 39 of 45 (87%) patients and p16 expression in 6 of 45 (13%) patients. A significant inverse correlation was observed between retinoblastoma and p16 expression as nearly all retinoblastoma negative cases were p16 positive, and vice versa. When examined for clinicopathological correlates, it was found that all 39 tumours that expressed retinoblastoma displayed marked keratinisation and were of low-moderate histological grade. Conversely, five of the six tumours that expressed p16 were found to be poorly differentiated, with minimal keratin expression. CONCLUSIONS: Salient relationships were seen between expression of retinoblastoma and p16 and keratinisation. A marked loss of keratin production was evident in the tumours that expressed p16. Tumours expressing retinoblastoma were seen to exhibit more widespread keratinisation. In addition, an inverse staining pattern was found for retinoblastoma and p16 as retinoblastoma-expressing tumours were nearly universally p16 negative and vice versa. No correlation of expression of either p16 or retinoblastoma was found with survival or stage. A link between the histologically observable morphology and expression of cell cycle regulatory protein with the expression of p16 and retinoblastoma has been suggested with keratinisation and differentiation of status.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Neoplasias de la Boca/metabolismo , Proteína de Retinoblastoma/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Diferenciación Celular , Femenino , Estudios de Seguimiento , Humanos , Queratinas/biosíntesis , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología , Proteínas de Neoplasias/metabolismo , Estadificación de Neoplasias , Análisis de Supervivencia
9.
J Natl Cancer Inst ; 63(2): 319-23, 1979 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-88537

RESUMEN

Hyperimmune New Zealand White rabbit sera prepared against partially purified tumor-associated antigens (TAA) of invasive cervical cancer tissues (CaCx's) were used to demonstrate TAA in CaCx's and circulating TAA (C-TAA) in sera from patients with cervical cancer or with head and neck cancer. Anti-CaCx serum adsorbed with pooled normal cervical tissue (NCx) antigen preparations and with lyophilized pooled normal human plasma gave precipitin in gel reactions with CaCx but not with NCx, which indicated the presence of TAA in CaCx. The adsorbed antisera reacted with sera from patients with cervical and head and neck cancers, which indicated the presence of C-TAA in such sera. False-positive reactions with control sera from normal humans or from patients with benign gynecologic diseases were much less frequently observed. Statistical analysis of data obtained by the testing of 96 coded serum samples from the National Cancer Institute-Mayo Clinic Serum Bank (Rochester, Minn.) revealed that the results were significant and that specificity was high but sensitivity of the assay was relatively low.


Asunto(s)
Antígenos de Neoplasias , Carcinoma de Células Escamosas/inmunología , Neoplasias de Cabeza y Cuello/inmunología , Neoplasias del Cuello Uterino/inmunología , Adulto , Anticuerpos Antineoplásicos , Antígenos Virales , Epítopos , Femenino , Humanos , Masculino , Embarazo , Pruebas Serológicas , Simplexvirus/inmunología , Neoplasias del Cuello Uterino/diagnóstico
10.
J Natl Cancer Inst ; 57(3): 599-602, 1976 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-978771

RESUMEN

Polyriboinosinic-polyribocytidylic acid (poly I - poly C), an interferon inducer, was administered in multiple doses of 0.3-75 mg/m2 to 26 patients with a variety of solid tumors, 9 with acute leukemia, and 2 with chronic myelogenous leukemia in blast crisis. Forty-four separate drug trials were comprised of various schedules and routes of administration. Toxic reactions included fever (in 66% of the trials), transient elevation of serum glutamic-oxaloacetic transaminase and serum glutamic-pyruvic transaminase (25%), minimal laboratory evidence of coagulation abnormalities (59%), and hypersensitivity (5%). These toxic manifestations did not relate to dose level or magnitude of interferon induction. Poly I - poly C administered iv induced low serum concentrations of interferon in 24/38 trials (63%), but the correlation between drug dose and peak interferon titer was not linear. Poly I - poly C administered iv or im was not effective as an inducer of interferon in the cerebrospinal fluid. Similarly, poly I - poly C administered im or by inhalation did not produce detectable serum levels of interferon. No patients experienced an objective tumor response to the administration of poly I - poly C, and most (76%) had progression of their disease while receiving the drug.


Asunto(s)
Leucemia/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Poli I-C/uso terapéutico , Enfermedad Aguda , Adolescente , Adulto , Niño , Preescolar , Femenino , Fiebre/inducido químicamente , Humanos , Interferones/sangre , Interferones/metabolismo , Masculino , Persona de Mediana Edad , Poli I-C/administración & dosificación , Poli I-C/efectos adversos
11.
Cancer Res ; 41(7): 2842-8, 1981 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6265069

RESUMEN

Evidence is presented indicating that the chemically transformed AKR-MCA and C3H/MCA-58 murine cell lines produce "transforming growth factor(s)" capable of inducing a transformed morphology and the ability to grow in soft agar in nontransformed, anchorage-dependent indicator cells. Serum-free medium conditioned by exposure to the chemically transformed cells was chromatographed on a Bio-Gel P-60 column after dialysis and lyophilization. Using the nontransformed mouse AKR-2B cells as the indicator cells, a peak of soft agar growth-stimulating activity was detected in the molecular weight range of 10,000 to 12,000. The soft agar growth-stimulating activity in pooled fractions from the AKR-MCA cells was shown to be trypsin and dithiothreitol sensitive and relatively heat stable; the activity was not destroyed by heating to 56 degrees for 30 min or to 100 degrees for 3 min. The pooled material also caused stimulation of growth in the soft agar of rat NRK cells and stimulation of DNA synthesis in the AKR-2B cells. The quantity required to give significant competition for binding to the epidermal growth factor receptor was about one order of magnitude greater than that required for stimulation of soft agar growth. Further separation of these polypeptide(s) by carboxymethylcellulose chromatography revealed three apparent peaks of soft agar growth-stimulating activity. Epidermal growth factor receptor-competing activity cochromatographed with the early minor soft agar growth-stimulating peak, whereas the two major peaks of soft agar growth-stimulating activity had no associated detectable competition for epidermal growth factor binding to its receptor. The data indicate that at least a major portion of the transforming growth factors produced by the chemically transformed cells is different from those described previously in murine sarcoma virus-transformed mouse cells and human tumor cells.


Asunto(s)
Transformación Celular Neoplásica/metabolismo , Péptidos/metabolismo , Animales , Unión Competitiva , Línea Celular , Transformación Celular Neoplásica/patología , Cromatografía por Intercambio Iónico , Factores Estimulantes de Colonias/análisis , ADN/biosíntesis , Ditiotreitol , Receptores ErbB , Calor , Ratones , Peso Molecular , Péptidos/análisis , Ratas , Receptores de Superficie Celular/metabolismo , Factores de Crecimiento Transformadores , Tripsina
12.
Cancer Res ; 42(7): 2633-8, 1982 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6979383

RESUMEN

Previous studies have shown that the nontransformed AKR-2B cells when arrested in the G1 phase of the cell cycle due to low-molecule-weight nutrient (amino acid) deficiency exhibit a 5- to 10-fold lower level of epidermal growth factor (EGF) receptor activity than do the same cells in the rapidly growing state or arrested in G1 due to growth factor deficiency. The chemically transformed AKR-MCA and C3H/MCA-58 cell lines spontaneously arrest growth in G1 due to nutrient deficiency when grown to saturation density in medium with 10% fetal bovine serum. An examination of 125I-labeled EGF binding in rapidly growing and G1-arrested AKR-MCA and C3H/MCA-58 cells showed that the G1-arrested chemically transformed cells also have a 10- to 20-fold reduction in the amount of 125I-labeled EGF binding relative to the same cells in the rapidly growing state. Stimulation of DNA synthesis in the arrested cells by the addition of serum-free medium caused a 6- to 10-fold increase in 125I-labeled EGF binding. This recovery of receptor activity was inhibited by actinomycin D and cycloheximide, suggesting that new messenger RNA synthesis as well as increased protein synthesis is necessary for the recovery of EGF binding. A comparison of EGF binding in C3H/MCA-58 cells and the nontransformed parent line (C3H/10T 1/2) in the rapidly growing state showed the same approximate level of receptor activity. However, the rapidly growing AKR-MCA cells had approximately one-tenth the amount of EGF binding as did the rapidly growing nontransformed parent line (AKR-2B). Scatchard analysis of binding data showed a 10-fold greater number of receptors in the AKR-2B cells relative to the AKR-MCA cells with a lesser difference in apparent receptor affinity. The chemically transformed BP-3T3, like the other two chemically transformed lines, was also demonstrated to arrest growth spontaneously due to nutrient deficiency with an associated 100-fold decrease in EGF binding. Rapidly growing BP-3T3 cells had only slightly less 125I-labeled EGF binding than did the nontransformed parent line (BALB-3T3) in the rapidly growing state. The data indicate that one mechanism for reduction of EGF binding in chemically transformed cells is the propensity of these cells to arrest growth in G1 at saturation density due to low-molecular-weight nutrient deficiency, a state associated with decreased EGF binding.


Asunto(s)
Ciclo Celular , Transformación Celular Neoplásica/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Aminoácidos/metabolismo , Animales , División Celular/efectos de los fármacos , Línea Celular , Transformación Celular Neoplásica/inducido químicamente , Cicloheximida/farmacología , Dactinomicina/farmacología , Ratones
13.
Cancer Res ; 50(16): 5184-7, 1990 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-1974168

RESUMEN

p185neu is the protein product of the HER2/neu protooncogene. This protein has characteristics of a tyrosine kinase growth factor receptor and is postulated to be important in human carcinogenesis. To define the significance of the expression of this protein in human non-small cell lung cancer, 55 tumors from patients with squamous cell carcinoma (16), adenocarcinoma (29), or large cell carcinoma (10) of the lung were examined for p185neu using immunohistological methods. Five of 16 squamous cell carcinomas and 10 of 29 adenocarcinomas were found to overexpress p185neu relative to levels of expression seen in uninvolved bronchiolar epithelium. For the adenocarcinomas, p185neu expression was associated with older age (66.6 +/- 10.1 versus 57.5 +/- 10.8 years) (P = 0.04) and shortened survival (83.7 +/- 94.1 versus 188.5 +/- 120 weeks) (P = 0.01). In this group, using Cox's multivariate survival analysis, p185neu expression was found to be a significant determinant of survival (P = 0.04) even after accounting for the effect of tumor stage. For the squamous cell carcinomas, p185neu expression was not correlated with any of our clinicopathological parameters. Our findings indicate that non-small cell lung cancers which express p185neu do so at levels higher than that found in normal bronchiolar epithelium, and expression in adenocarcinomas of the lung is independently associated with diminished survival intervals.


Asunto(s)
Adenocarcinoma/genética , Biomarcadores de Tumor/análisis , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogénicas/genética , Proto-Oncogenes , Adenocarcinoma/patología , Línea Celular , Femenino , Humanos , Sueros Inmunes , Neoplasias Pulmonares/patología , Masculino , Ploidias , Pronóstico , Proteínas Proto-Oncogénicas/análisis , Receptor ErbB-2 , Fumar , Células Tumorales Cultivadas/citología
14.
Cancer Res ; 44(8): 3561-9, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6744280

RESUMEN

Four new human non-small cell lung cancer cell lines have been established in vitro. These cell lines have been characterized by (a) growth of a tumor in nude mice with histopathology similar to that of the primary, (b) isoenzyme patterns phenotypically human and distinct from each other, (c) distinguishing karyotypic findings, (d) growth rate determinations, and (e) presence of epidermal growth factor receptors. Each of the cell lines will form colonies when directly seeded into a flask without soft agar. The development and availability of the four cell lines may facilitate in vitro studies of the biology of this common cancer. Their clonogenic potential may be of value in the study of sensitivity to antineoplastic agents. Their low passage level may mean that their antigens still resemble those of the primary tumor.


Asunto(s)
Adenocarcinoma/fisiopatología , Carcinoma de Células Escamosas/fisiopatología , Neoplasias Pulmonares/fisiopatología , Animales , División Celular , Línea Celular , Células Clonales , Técnicas de Cultivo/métodos , Humanos , Isoenzimas/análisis , Cariotipificación , Cinética , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Trasplante Heterólogo
15.
Transbound Emerg Dis ; 63(5): e347-59, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25516263

RESUMEN

West Nile virus (WNV) is a mosquito borne arbovirus that circulates within avian reservoirs. WNV can spill over into humans and Equidae that are dead-end hosts for WNV but suffer fever, acute morbidity and sometimes death. Outbreaks of WNV are common across Africa and Eastern Europe, and there have also been sporadic outbreaks in Spain and the Camargue Regional Park in France, but never in Great Britain (GB). These areas all fall along a major bird migration route. In this study, we analyse a scenario in which WNV is circulating in the Camargue or in other wetland areas in France and we estimate the risk of northward migrating passerine birds stopping in a WNV hotspot, becoming infected and carrying active infection to GB. If the disease were circulating in the Camargue during a single migratory season, the probability that one or more migrating birds becomes infected and lands in GB whilst still infected is 0.881 with 0.384 birds arriving in areas of suitable vector habitat. However, if WNV became established in the Grand Brière National Park or La Brenne Regional Park wetland areas further to the north, the model predicts that at least one infected bird will continue to GB. Thus, GB is at risk of WNV introduction from the Camargue, but the risk is considerably greater if WNV were to circulate further north than its previous focus in France, but this is highly sensitive to the force of infection in the infected area. However, the risk of establishment and infection of humans in GB is dependent upon a number of additional factors, in particular the vector and epidemiological situation in GB.


Asunto(s)
Aves/virología , Fiebre del Nilo Occidental/epidemiología , Virus del Nilo Occidental/aislamiento & purificación , Virus del Nilo Occidental/patogenicidad , Zoonosis/epidemiología , África , Animales , Culicidae/virología , Brotes de Enfermedades , Ecosistema , Femenino , Francia , Humanos , Masculino , Medición de Riesgo , Estaciones del Año , España , Procesos Estocásticos , Reino Unido/epidemiología , Zoonosis/virología
16.
J Clin Oncol ; 15(8): 2894-904, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9256133

RESUMEN

PURPOSE: The HER-2/neu gene codes for a membrane receptor protein that is homologous, but distinct from the epidermal growth factor receptor. This investigation was performed to validate fluorescence in situ hybridization (FISH) as a sensitive and specific method for assessing HER-2/neu gene amplification in archival tissue and to test whether this alteration is associated with poor prognosis. MATERIALS AND METHODS: HER-2/neu gene amplification was determined by FISH in 140 archival breast cancers, previously characterized for gene amplification by Southern hybridization or dot-blot hybridization, and for gene expression by Northern hybridization, Western immunoblot, or immunohistochemistry. A separate cohort of 324 node-negative breast cancers was assessed for amplification by FISH to determine the utility of HER-2/neu gene amplification. RESULTS: Relative to solid-matrix blotting procedures, FISH analysis of HER-2/neu gene amplification showed a sensitivity of 98% and a specificity of 100% in 140 breast cancers. Among patients treated by surgery only, the relative risks (relative hazard) of early recurrence (recurrent disease within 24 months of diagnosis), recurrent disease (at any time), and disease-related death were statistically significantly associated with amplification. The prognostic information contributed by HER-2/neu amplification was independent of the other markers studied. CONCLUSION: FISH was an alternative technique for determining gene amplification and had some distinct advantages over Southern hybridization. Our results demonstrate that HER-2/neu gene amplification in the absence of adjuvant therapy is an independent predictor of poor clinical outcome and is a stronger discriminant than tumor size. Women with small tumors that had gene amplification were at increased risk of recurrence and disease-related death.


Asunto(s)
Neoplasias de la Mama/patología , Amplificación de Genes , Receptor ErbB-2/genética , Anciano , Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/mortalidad , Femenino , Humanos , Immunoblotting , Hibridación Fluorescente in Situ , Metástasis Linfática , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Pronóstico , Sensibilidad y Especificidad , Tasa de Supervivencia
17.
J Clin Oncol ; 14(2): 503-13, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8636764

RESUMEN

PURPOSE: This study was designed to assess the anti-tumor activity of topotecan (TPT) in patients with advanced non-small-cell lung cancer (NSCLC) previously untreated with chemotherapy. PATIENTS AND METHODS: Patients with stage IIIB or IV NSCLC with measurable disease in nonradiated fields were eligible. Other eligibility criteria were Zubrod performance status (PS) < or = 2 and adequate renal and liver function. TPT was administered at a dose of 1.5 mg/m2/d for 5 days over 30 minutes every 21 days. Of 48 registered patients, 40 were fully assessable. Nineteen patients had adenocarcinoma (AD), 14 squamous carcinoma (SCC), and seven poorly differentiated carcinoma. RESULTS: Six patients (15%) achieved a partial remission (PR) (durations: 8, 14, 18, 28, 56, and 61 weeks) and four patients a minor response; 10 patients had stable disease and 20 patients progressive disease. The PR rate was 36% (five of 14 patients) in patients with SCC versus 4% (one of 26 patients) in those with other histologies (P = .014). The overall median survival time was 38 weeks and 30% of patients were alive at 1 year. Grade 3 to 4 granulocytopenia and thrombocytopenia occurred after 76% and 10% of courses administered, respectively. No grade 3 to 4 nonhematologic toxicities were observed. Grade 1 or 2 nonhematologic toxicities consisted of nausea (46% and 5%), vomiting (31% and 7%), and fatigue (53% and 16%). CONCLUSION: TPT at the dose and schedule used has moderate antitumor activity in NSCLC; its activity is mostly limited to patients with SCC. TPT is well tolerated, with myelosuppression of short duration being the most common and limiting toxicity.


Asunto(s)
Antineoplásicos/uso terapéutico , Camptotecina/análogos & derivados , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Adenocarcinoma/tratamiento farmacológico , Adulto , Anciano , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Camptotecina/administración & dosificación , Camptotecina/efectos adversos , Camptotecina/uso terapéutico , Carcinoma/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Células Escamosas/tratamiento farmacológico , Femenino , Humanos , Leucopenia/inducido químicamente , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Trombocitopenia/inducido químicamente , Topotecan , Resultado del Tratamiento
18.
Clin Cancer Res ; 2(5): 883-8, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-9816245

RESUMEN

Fluorescence in situ hybridization was performed on touch preparations from 55 primary infiltrating ductal carcinomas of the breast to determine numeric chromosome abnormalities. The frequency of aneusomy, measured by both nondisomy and chromosomal gain, was determined for chromosomes X, 4, 6-12, 17, and 18 with the use of chromosome-specific, alpha-satellite DNA probes. The presence of chromosome-specific numeric abnormalities was correlated with established clinicopathological parameters, including tumor size, lymph node involvement, tumor grade, estrogen receptor level, and menopause status. In addition, a case-control study was performed to explore a possible association between chromosome-specific aneusomy and recurrence in lymph-node-negative patients. Although chromosomes 8 and 6 were most frequently aneusomic, numeric abnormalities of chromosomes 4 and 11 were most strongly associated with established prognostic factors. For chromosomes 4 and 11, strong associations were found with tumor involvement of lymph nodes and increased tumor size, along with a weaker association with tumor grade. In addition, numeric abnormalities of the following chromosomes were associated with the corresponding prognostic factors: chromosomes X, 7, and 12 with lymph node status; chromosomes 10, 17, and 6 with tumor size; and chromosomes 7, 12, 17, and X with tumor grade. No correlations were observed with estrogen receptor level or menopause status. In the case-control study performed on isolated nuclei of paraffin-embedded tissue from lymph node-negative breast cancer patients (19 cases and 19 controls), the gain of chromosome 4 was correlated with disease progression. These findings suggest that chromosome-specific aneusomy is associated with certain established prognostic factors and may be associated with disease progression.


Asunto(s)
Aneuploidia , Neoplasias de la Mama/genética , Adulto , Anciano , Neoplasias de la Mama/patología , Estudios de Casos y Controles , Femenino , Humanos , Hibridación Fluorescente in Situ , Persona de Mediana Edad
19.
J Neuropathol Exp Neurol ; 46(5): 511-21, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3625232

RESUMEN

We report an experimental model of autoimmune inflammatory myopathy. Splenic cells from two inbred murine strains (BALB/c and SJL/J) are activated (immunized) in vitro by co-culture with their respective syngeneic skeletal muscle myotubes. Subsequent injection of the activated splenocytes with or without B. pertussis into the respective syngeneic hosts results in inflammatory myopathy in the SJL/J mice but never in the BALB/c mice. The muscle inflammation is very similar in appearance to human autoimmune inflammatory myopathies. The myositis is not effector cell-skeletal muscle specific because splenocytes activated by co-culture with smooth muscle will also elicit skeletal muscle lesions. Both strains of skeletal muscle appear to express class II (Ia) antigens and the splenocytes from both strains appear to be equally activated. Thus we postulate that the difference in the expression of myositis between the two strains is in the effector phase of the disease. Since SJL/J mice have vasoactive amine sensitive vascular systems and BALB/c do not, it is likely that activated splenocytes emigrate from muscle microvessels in the SJL/J strain whereas they cannot do so in the BALB/c strain. The most significant contribution of this model may be in its potential for addressing a sine qua non of cellular autoimmune disease, i.e. lymphocyte migration from the vascular compartment into the target tissue. Finally, the data support a cellular more than a humoral pathogenesis in this model.


Asunto(s)
Enfermedades Autoinmunes/patología , Miositis/patología , Animales , Modelos Animales de Enfermedad , Femenino , Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos , Músculos/patología , Miositis/etiología , Miositis/inmunología , Especificidad de la Especie , Bazo/citología
20.
Methods Enzymol ; 222: 281-99, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8412799

RESUMEN

These combined data support the concept that the procoagulant response elicited by mononuclear cells, particularly monocytes, is accomplished through regulated binding site-mediated (or perhaps "receptor"-mediated) assembly of proteolytic activities at their membrane surface. Because the work of several laboratories indicate that the monocytes provide the appropriate membrane surface for the assembly and function of all the coagulation complexes required for thrombin production in vivo, monocytes may provide a unique opportunity to investigate how coagulant reactions are regulated on cell surfaces through both receptor-mediated events as well as by channeling a product of one reaction to serve as a mediator of a second reaction.


Asunto(s)
Factor VIII/metabolismo , Factor V/metabolismo , Factor X/metabolismo , Factor Xa , Leucocitos Mononucleares/metabolismo , Monocitos/metabolismo , Tromboplastina/metabolismo , Separación Celular/métodos , Células Cultivadas , Endotoxinas/farmacología , Humanos , Cinética , Leucocitos Mononucleares/citología , Monocitos/citología , Monocitos/efectos de los fármacos , Linfocitos T/citología
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