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Contexte La litterature ne fournit pas d’indications claires concernant le traitement du cancer gastrique au stade IV. Buts Comparer la survie apres resection palliative et curative. Evaluer si les differentes localisations de metastases ont la meme valeur pronostique. Selectionner les patients a soumettre a une gestion multimodale agressive. Materiels et methodes Etude retrospective multicentrique concernant 282 patients avec cancer gastrique au stade IV. Resultats Le taux global de complications et de mortalite postoperatoire etait 26.2 % et 2,5 % respectivement. La chimiotherapie a ete administree de facon heterogene en 158 patients : neoadjuvant dans 43 cas (12,2 %), adjuvant dans 69 cas (25,0 %) et les deux dans 46 patients (16,3 %). Dans 49 cas la resection a ete associee a CHIP. Survie globale : 45,2 %, 20,2 % et 11,8 % a 1, 3 et 5 ans, mediane 10,9 mois. Survie selon curativite chirurgicale : La resection radicale R0 a un impact pronostique favorable (p Facteurs pronostiques Les variables avec un effet independant sur la survie etaient : nombre de ganglions reseques, extension de la lymphadenectomie (D), parametre N de pTNM et type histologique. Analyse sur patients R0 : Survie globale a 1, 3 et 5 ans 55,7 %, 28,3 % et 19,1 %, mediane 14,0 mois. Dans ces patients, les facteurs pronostiques ont montre un effet cumulatif. Conclusions Pour un sous-groupe de patients avec cancer gastrique au stade IV, la possibilite de soins efficaces existe, independamment du site de metastase, si l’on atteint une resection R0.

We report results from the experiment aimed at the artificial excitation of extremely low-frequency (ELF) electromagnetic waves with frequencies corresponding to the frequency of Schumann resonance. Electromagnetic waves with these frequencies can form a standing pattern inside the spherical cavity formed by the surface of the Earth and the ionosphere. In the experiment the ELF waves were excited by heating the ionosphere with X-mode HF electromagnetic waves generated at the High Frequency Active Auroral Research Program (HAARP) facility in Alaska. The experiment demonstrates that heating of the ionosphere can excite relatively large-amplitude electromagnetic waves with frequencies in the range 7.8–8.0 Hz when the ionosphere has a strong F layer, the frequency of the HF radiation is in the range 3.20–4.57 MHz, and the electric field greater than 5 mV/m is present in the ionosphere.

We present results from the statistical study of ULF waves detected by the fluxgate magnetometer in Gakona, Alaska during several experimental campaigns conducted at the High Frequency Active Auroral Research Program (HAARP) facility in years 2011–2013. We analyzed frequencies of ULF waves recorded during 26 strongly disturbed geomagnetic events (substorms) and compared them with frequencies of ULF waves detected during magnetically quiet times. Our analysis demonstrates that the frequency of the waves carrying most of the power in almost all these events is less than 1 mHz. We also analyzed data from the ACE satellite, measuring parameters of the solar wind in the L1 Lagrangian point between Earth and Sun, and found that in several occasions there is a strong correlation between oscillations of the magnetic field in the solar wind and oscillations detected on the ground. We also found several cases when there is no correlation between signals detected on ACE and on the ground. This finding suggests that these frequencies correspond to the fundamental eigenfrequency of the coupled magnetosphere–ionosphere system, and the amplitude of these waves can reach significant magnitude when the system is driven by the external driver (for example, the solar wind) with this particular frequency. When the frequency of the driver does not match the frequency of the system, the waves still are observed, but their amplitudes are much smaller.

Santander and Huila are the largest producers of Flue-cured tobacco in Colombia. They differ in their production systems and, consequently, in their production costs. Costs provide valuable information on the efficiency of resource use, a variable that determines the profitability of the crop. The purpose of this study was to determine and analyze the structure of production costs by department, as well as, their differences and possibilities for reduction. Data for the analysis was obtained from the records of Protabaco and surveys of 50 producers (farms) in the municipalities of Campoalegre and Garzon in Huila, and Capitanejo and Enciso in Santander. The results say the costs of the most important factors of production in both departments are: labor, inputs and services. Huila has higher total costs per hectare than Santander, but similar unit costs. Huila has a higher technological level of production, more capital and greater surface area per crop unit than Santander. Production costs can be reduced by increasing the availability of investment capital, and irrigation water, as well as, more efficient management of fertilization, cultural practices and mechanization of land preparation.

In Colombia, there is little information on tobacco crops and the effect of fertilization on the nutrient content of leaves. The aim of this study was to determine the contents of mineral nutrients in tobacco (Nicotiana tabacum L., cv. flue-cured) plants subjected to different fertilizer rates and sources in two municipalities in the Huila Province (Colombia). Six foliar analyses, with three measurements from vegetative growth to flowering and three measurements during harvest, were carried out. Seven treatments, including six fertilization alternatives (three doses and two alternative sources of application) and a commercial control, were evaluated. The contents of the macronutrients N, P, K, Ca, Mg, S, and chlorine in the leaves were evaluated. The leaf analyses performed from vegetative growth to flowering showed differences in the foliar contents of nitrogen, calcium, magnesium, and chlorine between the two municipalities and over time, with contents that increased. During this stage, the elements with higher accumulations in the plants included N, K, and Ca. At harvest, the contents of potassium, magnesium, and calcium decreased over time. For nitrogen, sulfur and chlorine, differences were found in the time-municipality interaction. En Colombia existe poca información del cultivo de tabaco y del efecto de la fertilización en el contenido de nutrientes minerales en hoja. El objetivo del presente trabajo fue determinar el contenido de nutrientes del tabaco cv. Virginia (Nicotiana tabacum L.) durante el ciclo de cultivo bajo diferentes dosis y fuentes de fertilización, en dos municipios del departamento Huila (Colombia). Se evaluaron siete tratamientos correspondientes a seis alternativas de fertilización (tres dosis y dos alternativas de fuentes de aplicación) y un testigo comercial, para conocer el contenido de nutrientes en hojas, se realizaron seis análisis foliares, tres durante crecimiento vegetativo hasta floración y tres durante la cosecha. Los macronutrientes evaluados en hojas fueron N, P, K, Ca, Mg, S y cloro. De acuerdo a los resultados de los análisis foliares realizados en durante crecimiento vegetativo hasta floración, se encuentran diferencias en el contenido de nitrógeno, calcio, magnesio y cloro en los dos municipios y a través del tiempo, presentándose aumento en los contenidos. Durante esta etapa los elementos que presentan mayor acumulación en las plantas fueron N, K y Ca. Durante la cosecha el contenido de potasio, magnesio y calcio disminuyó a través del tiempo. Para nitrógeno, azufre y cloro se presentaron diferencias en la interacción tiempo-municipio.

Phytosociological studies allow for the characterization and descriptive analysis of weed communities in crops. This study aimed to characterize the weed communities associated with weed crops in the "Centro, Meseta, and Norte" zones of the Tolima Department. The study was conducted in 96 commercial lots, in which a 1 ha area was marked off for the sampling. The development stage, density and cover of the weeds were evaluated. The importance value index, the alpha diversity indices of Shannon-Wiener, Simpson and uniformity as well as the similarity indices of Jaccard, Sorensen and Steinhaus were calculated. For the entire department, 42 weed species were identified, with Echinochloa colona being the principal one in all of the zones. In the Centro zone, 27 species were identified; in the Meseta zone, 31 species were identified; and, in the Norte zone, 38 species were identified. The alpha indices demonstrated that the Meseta zone was the most diverse. The Jaccard and Sorensen indices showed dissimilarity in the weed community for all of the comparisons of the zones. The Steinhaus coefficient registered the highest similarity intensity between the Centro and Norte zones. Los estudios fitosociológicos permiten caracterizar y hacer análisis descriptivos de las comunidades de malezas de cultivos. Este trabajo tuvo como objetivo caracterizar las poblaciones de malezas asociadas a cultivos de arroz de las zonas Centro, Meseta y Norte del departamento del Tolima. Los levantamientos fueron realizados en 96 lotes comerciales, en cada lote se demarcó un área de evaluación de 1 ha en la cual se realizaron los muestreos. Se evaluó el estado de desarrollo, densidad y cobertura de las malezas. Se calculó el índice de valor de importancia, los índices de diversidad alfa de Shannon-Wiener, Simpson y de uniformidad así como los índices de similitud de Jaccard, Sorensen y Steinhaus. En todo el departamento se identificaron 42 especies de malezas siendo Echinochloa colona, la principal en todas las zonas. En la zona Centro fueron identificadas 27 especies; en la zona Meseta 31 y en la zona Norte 38. Los índices alfa registraron que la zona Meseta fue la más diversa. Los índices Jaccard y Sorensen mostraron disimilitud en la comunidad de malezas en todas las comparaciones de las zonas. El coeficiente Steinhaus registró mayor intensidad de similitud entre las zonas Centro y Norte.

Leiomyosarcoma of the broad ligament is a rare tumor, since only 12 cases have been reported so far in the literature. A 53-year-old patient was diagnosed with leiomyosarcoma of the broad ligament at the Department of Gynecology Oncology of the National Cancer Research Institute in Genoa. The tumor had low mitotic activity and less than ten mitotic figures were found for ten high-power fields. The treatment consisted of total abdominal hysterectomy and bilateral salpingo-oophorectomy with bilateral ureteral neoanastomosis and omentectomy. The patient has not received either radiotherapy or chemotherapy, considering the low grade of malignancy, but she is only followed up on an outpatient basis. No evidence of metastasis has been noted after a follow-up of 13 months. It is concluded that low-grade leiomyosarcoma of the broad ligament should be treated only with surgery.

Para el cultivo del arroz en Colombia se reportan más de 70 especies de malezas que, por orden de competitividad biológica y económica, las malezas gramíneas son las de mayor afección al cultivo. Por su nocividad, las más importantes son: Echinochloa colonum (L.) Link, Oryza sativa L. (arroz rojo), Cyperus rotundus L., Rottboellia cochinchinensis U., Fimbristylis annua (Alt.) Riets, Murdania nudiflora (L.) Brenan, y Digitaria sanguinalis (L.) Scop. La ausencia de trabajos realizados sobre Digitaria sanguinalis (L) Scop., dirigidos al conocimiento de sus aspectos biológicos, el aumento en la incidencia y agresividad de la especie en los cultivos de arroz y sorgo en la zona norte del Tolima, justificó la elaboración del presente estudio, para el cual se propusieron los siguientes objetivos: identificar aspectos dela biología y fenología, evaluar el banco de semillas y medir el efecto de la competencia de diferentes densidades de población de Digitaria sanguina lis (L.) Scop. en los cultivos de arroz en Lérida, (Tolima). Los momentos de mayor suceptibilidad a la presencia de malezas en el cultivo del arroz fueron: a) Germinación: D. sanguinalis completó esta fase en los tres primeros días después de humedecer el terreno, a diferencia de las semillas de arroz que requirieron dos días más. b) Macollamiento: D. sanguinalis inició esta fase a los 20 días, a diferencia de las plantas de arroz que iniciaron a los 28 días. e) Formación de Panícula: D. sanguina lis, la inició a los 65 días, a diferencia del arroz que inició a los 70 días. d) Maduración de semillas: Las semillas de D. sanguinalis necesitaron 110 días para completar esta fase, las semillas de las plantas de arroz necesitaron 10 días más. D sanguinalis comenzó a liberar semillas a los 100 días aproximadamente. Mediante la emergencia de plántulas selogró estimar la composición del Banco de Semilla, obteniendo los mayores porcentajes de emergencia en Murdania nudiflora, con 42,5 %, y el grupo de las dicotiledóneas, con 39 %. Para las especies gramíneas, D.sanguina lis, 12,5 % y Echinochloa sp., 6 %. Las variables de mayor sensibilidad a la competencia interespecífica cultivo maleza fueron número promedio de macollas viables, con reducción del 25 %, a una densidad de una planta/m2; altura de planta, con reducción del 8,7; 21; y 23,5 %, a densidades de una, cinco y veinte plantas/m" de D. sanguinalis respectivamente. Los diferentes componentes de rendimiento del arroz se vieron afectados con densidades superiores a una planta por m2. Los resultados obtenidos, al estudiar los aspectos de la biología de Digitaria sanguinalis, tales como la cantidad de semillas en el banco de suelo, la sincronía de su ciclo biológico con el ciclo biológico de las plantas de cultivo y alta capacidad de competencia, señala, para su manejo, laplaneación e implementación de tratamientos especílicos en los ciclos del cultivo de arroz.In the rice crop in Colombia there are 70 species of weed. The gramineae species are the plants in direct biological and economical competition with the crop. Echinochloa cotonum (L.) Link, Oryza sativa L. (red rice) Cyperus rotundus L. ,Rottboellia cochinchinensis U., Fimbristylis annua (Alt.) Riets , Murdania nudiflora (L.) Brenan and Digitaría sanguinalis (L.) Scop., are the most common weeds in the rice crop. This work was necessary tor two reasons: there is nowork presenting the biological aspects of D. sanguinalis, and also there is an increasing population of weed in sorghum and rice crops in Lerida in the region Tolima. The objectives were: to know Phenology development, to evaluate the seed bank and to know the competitive ellects of three densities (one, live and twenty ptantslrn-) of Digitaria sanguinalis in the rice crop. Four stages were affected considerably in the rice plants by the presence of D. sanguinalis. Germination: D. sanguinalis needed three days of growth after the wetting of the land, however the rice seeds required two days more; Tillering: D. sanguinalis began this phase in 20 days asopposed to rice plants that began in 28 days. Booting: D. sanguinalis began this state in the 65 days compared with the rice plants, that took 70 days. Ripening: The seeds of D. sanguinalis needed 110 days to complete this phase with the seeds, needing 10 days more. D. sanguinalis began to free seeds at 100 days approximately. The method to evaluate the composition of the seed bank, was the emergence of seedlings obtaining the greater percentages M. nudiflora with 42,6 %, the second level the group frorn the broad lealwith 39 %, D. sanguinalis with 12,5 % and Echinochloa sp., with 6 %. The results of the plant competition were: reduction in the tillering number by 25 %, to a density of a plant/m2 ; plant height, with reduction of the 8,7, 21 and 23,5 r to density of one, live and twenty plantslrn of D. sanguinalis respectively. The different yield components of the rice were affected by densities superior to a plant by m2. The results obtained upon studying the aspects of the biology of Digitaria sanguinalis, such as, the quantity of seeds in the soil bank, the similar development of their biological cycles of the competition weed and cultivated plants it is necessary to a plan a specilic treatments for implementation in the cycles of the rice crop.

The need for endometrial surveillance in breast cancer patients undergoing adjuvant treatment with tamoxifen is still controversial. In this study, 164 asymptomatic breast cancer patients (110 on treatment with tamoxifen, 20 mg/day, and 54 controls) were examined with pelvic ultrasound and endometrial biopsy. No differences in ultrasound and biopsy findings were observed in the pre- and perimenopausal group between patients treated with tamoxifen and controls. Postmenopausal patients on tamoxifen had a significantly thicker endometrium (mean+/-SD, 7.2+/-8.5 vs. 1.5+/-4.3 mm, p=0.00002) and significantly larger uterine volume (mean+/-SD, 63.2+/-39.9 vs. 43.7+/-38.8 cm3, p=0.0001) than controls. Fifty-four percent of patients on tamoxifen had an endometrial thickness > or = 5 mm, often with multiple irregular sonolucencies suggesting the presence of cysts. Ultrasound findings, however, did not correlate with the presence of endometrial abnormalities on biopsy, and no endometrial cancer or atypical hyperplasia were found. This lack of correlation makes questionable the use of routine sonography in asymptomatic breast cancer patients on tamoxifen. Obtaining routine endometrial samples, on the other hand, may be difficult in some patients because of cervical stenosis or refusal. Until the benefits of endometrial surveillance will be proved, asymptomatic patients should not be submitted routinely to ultrasound examination or biopsy, but encouraged to report promptly any abnormal vaginal bleeding.

Santander and Huila are the largest producers of Flue-cured tobacco in Colombia. They differ in their production systems and, consequently, in their production costs. Costs provide valuable information on the efficiency of resource use, a variable that determines the profitability of the crop. The purpose of this study was to determine and analyze the structure of production costs by department, as well as, their differences and possibilities for reduction. Data for the analysis was obtained from the records of Protabaco and surveys of 50 producers (farms) in the municipalities of Campoalegre and Garzon in Huila, and Capitanejo and Enciso in Santander. The results say the costs of the most important factors of production in both departments are: labor, inputs and services. Huila has higher total costs per hectare than Santander, but similar unit costs. Huila has a higher technological level of production, more capital and greater surface area per crop unit than Santander. Production costs can be reduced by increasing the availability of investment capital, and irrigation water, as well as, more efficient management of fertilization, cultural practices and mechanization of land preparation Los departamentos Santander y Huila son los mayores productores de tabaco Virginia en Colombia. Éstos presentan diferencias en sus sistemas de producción y, en consecuencia, en sus costos de producción. Los costos brindan información valiosa sobre la eficiencia del uso de recursos, variable que determina la rentabilidad del cultivo. El propósito del presente trabajo fue determinar y analizar la estructura de costos de producción por departamento, así como sus diferencias y sus posibilidades de reducción. La información para el análisis se obtuvo de los registros de Protabaco y de encuestas hechas a 50 productores (fincas) pertenecientes a los municipios Campoalegre y Garzón en Huila, y a Capitanejo y Enciso en Santander. Los resultados dicen que los costos de los factores de producción más importantes en ambos departamentos son: mano de obra, insumos y servicios. Huila tiene mayores costos totales por hectárea que Santander, pero similares costos unitarios. Huila tiene un mayor nivel tecnológico de producción, mayor capital y mayor superficie por unidad de cultivo que Santander. Los costos de producción se pueden reducir con una mayor disponibilidad de capital de inversión y agua para riego, así como con un manejo más eficiente de la fertilización, de labores culturales y de mecanización de la preparación del terreno

Four castor materials were evaluated in 2009 in the middle region of Valle del Sinu, Colombia. The variables were phonological development, plant height, seed production and oil yield, in order to determine the best material for commercial purposes. All materials reported high yields of oil seeds and highlighting the commercial genotype Nordestina BRS149, 2.2 t ha-1 seed and 47% oil content. Planting distances were 1.5 x 1.5 m and 2.0 x 2.0 m, with densities of 6,666 and 3,906 plants ha-1, respectively. The plant height, seed productivity and oil yield showed significant differences for the interaction density × material; while comparing each material density, seed production only showed differences. These variables were significantly different between population densities, which shows that the higher the plant height, lower productivity. The planting distance of 2.0 x 2.0 m, provides higher productivity per plant values but seed oil yields were not different between densities. The oil quality parameters were assessed using free fatty acid value, iodine, acidity index, saponification, refraction and specific gravity, found that planting distance does not affect the quality of oil.

The problem our team addresses is best communicated in the following question: Given the number of merchants, consumers, and financial institutions in the U.S., how can we build a record-keeping system that improves the usability, accessibility, and sustainability of consumer transaction records?

Se llevó a cabo el reconocimiento y la caracterización de la comunidad de arvenses asociadas a un cultivo de rosa bajo invernadero, mediante un muestreo dirigido en el cual se consideraron algunos atributos poblacionales, tales como densidad, cobertura y frecuencia. Dichos atributos fueron evaluados en dos estilos de siembra (camas levantadas y confinadas), y adicionalmente en los bordes internos y externos de los invernaderos. Se registraron 46 especies pertenecientes a 41 géneros, 23 familias, 18 órdenes y tres subclases. El índice de diversidad (H) de la comunidad alcanzó un valor de 1,9. Por su parte, el índice de equidad ascendió a 0,497. Esto indica la alta dominancia de unas pocas especies, que fueron Cardamine hirsuta (dentro del invernadero, principalmente en las camas confinadas) y Pennisetum clandestinum (en los bordes del invernadero, sobre todo externos) las cuales contribuyeron con el 67% de la cobertura total. Estas fueron también las especies más abundantes. Se evidenció una clara diferencia entre los dos tipos de cama, y entre estos y los bordes. The community of weeds associated to a rose crop grown under greenhouse conditions was recognized and characterized by means of supervised sampling, analyzing a series of population attributes such as density, coverage and frequency. These were assessed in two different planting modes (confined and elevated beds), and additionally on the external and internal edges of the greenhouses. Forty six species belonging to 41 genera, 23 families, 18 orders and three subclasses were identified. Diversity index (H) of the community was 1.9, whereas equity index was 0.497, indicating the dominance of a few species, namely Cardamine hirsuta (inside the greenhouses, mainly in the confined beds), and Pennisetum clandestinum (outside the greenhouses, mainly on the edges), which responded for 67% of the whole plant coverage. These were also the most abundant species. A clear difference was detected between the two planting modes, and between them and the edges.

Eleven patients (pts) with advanced refractory breast carcinoma were treated with combination chemotherapy (Planovin) including mitoxantrone 10 mg/m 2 on day 1, cisplatin 60 mg/m 2 on days 1-2, methotrexate 200 mg/m 2 on day 15, vincristine 2 mg on day 15, leucovorin 15 mg/m 2 on days 15-16 every 3 weeks. Five patients (41%) achieved an objective response with one complete regression. The median duration of response was 4.5 months and the median duration of survival was 8 months. Drug related toxicity consisted mainly of leukopenia (8 pts), nausea and vomiting (6 pts), anemia (7 pts) and thrombocytopenia (4 pts)

An oral chemotherapy schedule based on idarubicin and cyclophosphamide was evaluated in 31 advanced breast cancer patients. Out of 27 patients evaluable for response, 1 (3.7%) achieved a complete response and 5 (18.5%) a partial response, with an objective response rate of 22.2% (95% confidence limits 8.6-42.3%). The median time to progression was 7 months (range 3-12). Fourteen patients (51.9%) showed a disease stabilization, and 7 progressed (25.9%). Toxicity was mild. Considering the low response rate, but also the advantages of oral chemotherapy and the mild toxicity observed, oral idarubicin plus cyclophosphamide can be considered as a second-choice regimen in advanced breast cancer.

Eight factors were analyzed for prognostic significance in univariate analyses in a series of 76 women with stage IV ovarian carcinoma treated with combination chemotherapies including cisplatin or carboplatin. The clinical objective and pathologic complete response rates were 51.2% and 27.3%, respectively. Median overall survival and progression-free survival were 15 and 7 months, respectively. No variables reached statistical significance. Trends toward better survival were noted for grades 1 and 2 for the adriamycin-containing regimen. Using progression-free survival as an end point, significant prognostic factors included complete clinical or pathologic response. Our data confirm that the standard approach is unlikely to modify the clinical outcome of stage IV ovarian cancer. New treatment modalities including high-dose-intensity regimens and neo-adjuvant chemotherapy delivered before surgery could improve clinical results. Moreover, biologic characterization of ovarian tumors may provide information to design specifically targeted treatment.

Rat cerebellar granule cells differentiated in culture were fed [1-(3)H]sphingosine, allowing the metabolic radiolabelling of all cell sphingolipids and phosphatidylethanolamine. A detergent-insoluble sphingolipid-enriched membrane fraction, containing about 60% of cell sphingolipids, but only trace amounts of phosphatidylethanolamine, was prepared from [1-(3)H]sphingosine-fed cells by sucrose gradient centrifugation. This fraction was enriched in the Src family protein tyrosine kinases c-Src, Lyn and Fyn and in the GPI-anchored neuronal adhesion molecule TAG-1. The cell lysate and the sphingolipid-enriched membrane fraction were subjected to immunoprecipitation with anti-GD3 ganglioside monoclonal antibody R24, under experimental conditions designed to preserve the integrity of the domain. The radioactive lipid composition of the immunoprecipitates obtained from the cell lysate and from the sphingolipid-enriched fraction were very similar, and closely resembled the sphingolipid composition of the whole sphingolipid-enriched membrane fraction. In fact, the immunoprecipitates contained, together with GD3 ganglioside, all cell glycosphingolipids and sphingomyelin, whereas they did not contain phosphatidylethanolamine. Moreover, cholesterol and phosphatidylcholine were detected in the immunoprecipitates by qualitative TLC analysis followed by colourimetric visualization. c-Src, Lyn, Fyn and TAG-1 were associated with the anti-GD3 antibody immunoprecipitate. These proteins were not detected in the immunoprecipitates obtained under experimental conditions different from those designed to preserve the integrity of the domain. These data suggest that a membrane domain containing cholesterol, phosphatidylcholine, sphingolipids and proteins can be separated from the total cell membranes by anti-GD3 antibody immunoprecipitation, and that the association of c-Src, Fyn, Lyn, and TAG-1 with the sphingolipid-enriched domain is mediated by the interaction with a complex lipid environment, rather than by specific interactions with a single sphingolipid species.

In summary, PDAPP mice overexpressing a mutation associated with some cases of familial early-onset AD express several of the major pathological hallmarks associated with AD. Amyloid plaques in PDAPP mice appear quite similar to A beta deposits in AD as shown by a variety of different antibodies and stains, and are of both the diffuse and compacted varieties. Additionally, a subset of these amyloid plaques appear to be neuritic plaques. Neurodegenerative changes, including the loss of synaptic and dendritic proteins, abnormal phosphorylation of cytoskeletal elements, subcellular degenerative changes, and the deposition of lysosomal and acute phase proteins has also been seen in PDAPP mouse brains. Reactive astrocytosis and microgliosis have also been observed in association with the amyloid plaques in the PDAPP mice. No neurofibrillary tangles or paired helical filaments have been found in the mice to date. It remains unknown whether mice are capable of generating these in a manner comparable to AD in less than two years. Extensive behavioral analyses are currently being performed in these mice, and preliminary results indicate that the PDAPP mice are significantly impaired on a variety of different learning and memory tests. In conclusion, the PDAPP mouse model doesn't display all the pathological hallmarks of AD, but it does display most of them in a robust manner that increases with age and gene dosage. Therefore, this transgenic model provides evidence that alterations in APP processing and A beta production can result in AD-like neuropathology, can contribute to a mechanistic understanding of AD (since examination of AD brains yields a static view, and we are unable to view the development of various pathological changes), as well as providing an useful animal model for the testing of various therapeutic interventions directed towards specific aspects of the neurodegenerative process.

The need for endometrial surveillance in breast cancer patients undergoing adjuvant treatment with tamoxifen is still controversial. In this study, 164 asymptomatic breast cancer patients (110 on treatment with tamoxifen, 20 mg/day, and 54 controls) were examined with pelvic ultrasound and endometrial biopsy. No differences in ultrasound and biopsy findings were observed in the pre- and perimenopausal group between patients treated with tamoxifen and controls. Postmenopausal patients on tamoxifen had a significantly thicker endometrium (mean+/-SD, 7.2+/-8.5 vs. 1.5+/-4.3 mm, p=0.00002) and significantly larger uterine volume (mean+/-SD, 63.2+/-39.9 vs. 43.7+/-38.8 cm3, p=0.0001) than controls. Fifty-four percent of patients on tamoxifen had an endometrial thicknessor = 5 mm, often with multiple irregular sonolucencies suggesting the presence of cysts. Ultrasound findings, however, did not correlate with the presence of endometrial abnormalities on biopsy, and no endometrial cancer or atypical hyperplasia were found. This lack of correlation makes questionable the use of routine sonography in asymptomatic breast cancer patients on tamoxifen. Obtaining routine endometrial samples, on the other hand, may be difficult in some patients because of cervical stenosis or refusal. Until the benefits of endometrial surveillance will be proved, asymptomatic patients should not be submitted routinely to ultrasound examination or biopsy, but encouraged to report promptly any abnormal vaginal bleeding.

Para el cultivo del arroz en Colombia se reportan más de 70 especies de malezas que, por orden de competitividad biológica y económica, las malezas gramíneas son las de mayor afección al cultivo. Por su nocividad, las más importantes son: Echinochloa colonum (L.) Link, Oryza sativa L. (arroz rojo), Cyperus rotundus L., Rottboellia cochinchinensis U., Fimbristylis annua (Alt.) Riets, Murdania nudiflora (L.) Brenan, y Digitaria sanguinalis (L.) Scop. La ausencia de trabajos realizados sobre Digitaria sanguinalis (L) Scop., dirigidos al conocimiento de sus aspectos biológicos, el aumento en la incidencia y agresividad de la especie en los cultivos de arroz y sorgo en la zona norte del Tolima, justificó la elaboración del presente estudio, para el cual se propusieron los siguientes objetivos: identificar aspectos dela biología y fenología, evaluar el banco de semillas y medir el efecto de la competencia de diferentes densidades de población de Digitaria sanguina lis (L.) Scop. en los cultivos de arroz en Lérida, (Tolima). Los momentos de mayor suceptibilidad a la presencia de malezas en el cultivo del arroz fueron: a) Germinación: D. sanguinalis completó esta fase en los tres primeros días después de humedecer el terreno, a diferencia de las semillas de arroz que requirieron dos días más. b) Macollamiento: D. sanguinalis inició esta fase a los 20 días, a diferencia de las plantas de arroz que iniciaron a los 28 días. e) Formación de Panícula: D. sanguina lis, la inició a los 65 días, a diferencia del arroz que inició a los 70 días. d) Maduración de semillas: Las semillas de D. sanguinalis necesitaron 110 días para completar esta fase, las semillas de las plantas de arroz necesitaron 10 días más. D sanguinalis comenzó a liberar semillas a los 100 días aproximadamente. Mediante la emergencia de plántulas selogró estimar la composición del Banco de Semilla, obteniendo los mayores porcentajes de emergencia en Murdania nudiflora, con 42,5 %, y el grupo de las dicotiledóneas, con 39 %. Para las especies gramíneas, D.sanguina lis, 12,5 % y Echinochloa sp., 6 %. Las variables de mayor sensibilidad a la competencia interespecífica cultivo maleza fueron número promedio de macollas viables, con reducción del 25 %, a una densidad de una planta/m2; altura de planta, con reducción del 8,7; 21; y 23,5 %, a densidades de una, cinco y veinte plantas/m" de D. sanguinalis respectivamente. Los diferentes componentes de rendimiento del arroz se vieron afectados con densidades superiores a una planta por m2. Los resultados obtenidos, al estudiar los aspectos de la biología de Digitaria sanguinalis, tales como la cantidad de semillas en el banco de suelo, la sincronía de su ciclo biológico con el ciclo biológico de las plantas de cultivo y alta capacidad de competencia, señala, para su manejo, laplaneación e implementación de tratamientos especílicos en los ciclos del cultivo de arroz. In the rice crop in Colombia there are 70 species of weed. The gramineae species are the plants in direct biological and economical competition with the crop. Echinochloa cotonum (L.) Link, Oryza sativa L. (red rice) Cyperus rotundus L. ,Rottboellia cochinchinensis U., Fimbristylis annua (Alt.) Riets , Murdania nudiflora (L.) Brenan and Digitaría sanguinalis (L.) Scop., are the most common weeds in the rice crop. This work was necessary tor two reasons: there is nowork presenting the biological aspects of D. sanguinalis, and also there is an increasing population of weed in sorghum and rice crops in Lerida in the region Tolima. The objectives were: to know Phenology development, to evaluate the seed bank and to know the competitive ellects of three densities (one, live and twenty ptantslrn-) of Digitaria sanguinalis in the rice crop. Four stages were affected considerably in the rice plants by the presence of D. sanguinalis. Germination: D. sanguinalis needed three days of growth after the wetting of the land, however the rice seeds required two days more; Tillering: D. sanguinalis began this phase in 20 days asopposed to rice plants that began in 28 days. Booting: D. sanguinalis began this state in the 65 days compared with the rice plants, that took 70 days. Ripening: The seeds of D. sanguinalis needed 110 days to complete this phase with the seeds, needing 10 days more. D. sanguinalis began to free seeds at 100 days approximately. The method to evaluate the composition of the seed bank, was the emergence of seedlings obtaining the greater percentages M. nudiflora with 42,6 %, the second level the group frorn the broad lealwith 39 %, D. sanguinalis with 12,5 % and Echinochloa sp., with 6 %. The results of the plant competition were: reduction in the tillering number by 25 %, to a density of a plant/m2 ; plant height, with reduction of the 8,7, 21 and 23,5 r to density of one, live and twenty plantslrn of D. sanguinalis respectively. The different yield components of the rice were affected by densities superior to a plant by m2. The results obtained upon studying the aspects of the biology of Digitaria sanguinalis, such as, the quantity of seeds in the soil bank, the similar development of their biological cycles of the competition weed and cultivated plants it is necessary to a plan a specilic treatments for implementation in the cycles of the rice crop.

El objetivo de este trabajo fue determinar el comportamiento de la avena silvestre (Avena fatua L.) sobre el cultivo de trigo (Triticum aestívum LO.). Estainvestigaciónfue desarrollada en el Centro Agropecuario , Universidad Nacional de Colombia del municipio de Mosquera, Cundinamarca, principalmente para determinar la variación de las poblaciones de la avena silvestre mediante el establecimiento de 8 cohortes a intervalos de 15 días cada una. Se evaluaron los cambios fenológicos en cada cohorte dos veces por semana. También, fue evaluado el impacto de la competencia a través del peso seco de las plantas. El trabajo se desarrollócon diseño experimental de bloques completos al azar, con cuatro replicas y cada tratamiento se acompañó con dos testigos: una parcela siempre limpia y otra siempre enmalezada. Se realizó la prueba de Duncan para las variables significativas. La emergencia de plantas de avena se presentó durante todo el ciclo del cultivo. Las plantas de las primeras cohortes de avena fueron tan altas como las plantas de cultivo. La densidad de plantas y el peso seco de estas primeras 5 cohortes fueron superiores a los de las3 cohortes finales. Las plantas de las cohortes 6 a, 7 a y e-. presentaron menor número de tallos y menor peso seco por planta. Estas diferencias hacen que las plantas de las primerascohortes presentaran mayor capacidad de competencia. The objective of this study was to determine the behaviour of wild oats (Avena fatua L.) in a wheat crop (Tritícum aestivum LO.). This research was conducted at the Centro Agropecuario "Marengo" , Universidad Nacional de Colombia, near the town of Mosquera, Cundinamarca. In order to determine the variation of Avena fatua populations, 8 succesive cohorts were established with intervals of 15 days. The experimental design used was randomized complete blocks with tour replications. In addition to the the eight treatments (cohorts) there were two check plots, one was kept always clean and the other was kept always weedy. Each cohort was examined for phenological changes twice per week, and the impact of competition was established on the basis of dry weight of each plant. Differences were observed among the oat cohorts. In the tirst five cohorts, oat plants were as tall as wheat plants, and density and dry weight were higher than for the last three cohorts. Plants from cohorts 6 th 7th and 8th had less number of stems and lower dry weight. Thesedifferences among cohorts suggest a stronger competitive impact on crop yield from the earlier oats populations.

It has been demonstrated that the prognosis of ovarian cancer is influenced by the dose intensity of cytotoxic treatment. The impact of received dose intensity of platinum-based combination chemotherapy on disease outcome was analysed in 226 stage III-IV ovarian cancer patients entered into two prospective randomised trials. All patients received either cisplatin or carboplatin and cyclophosphamide with or without doxorubicin for six courses after primary surgery. The impact of the received dose intensity of each drug (RDI), the average received dose intensity of the treatment regimen (ARDI) and the relative total drug dose (RTD) on progression-free survival (PFS) and survival were analysed. In the 198 patients receiving the full six courses of treatment, RDI of cisplatin or carboplatin, ARDI and RTD were0.76 in 74.2, 61.1 and 65.1% of cases, respectively. Although the differences were not significant, pathological complete response was more frequently observed in the group of patients with ARDI0.75, whereas the partial response rate was higher in the ARDIor = 0.76 group. Median survival and PFS were 19 and 13 months; 22 and 10 months; 23 and 13 months for the groups of patients receiving chemotherapy at a ARDI of0.75,or = 0.76-0.99 and1.00, respectively (P = not significant). It appears that modest dose modifications and brief treatment delays during first-line platinum-based chemotherapy do not affect response rate, survival and PFS in advanced ovarian cancer patients.

147 stage II pre- and perimenopausal breast cancer patients were treated with cyclophosphamide-methotrexate-5-fluorouracil (CMF)- based adjuvant regimens. 103 (72%) patients became amenorrheic during or immediately after the end of the chemotherapy program. Univariate analyses for age, menstrual status, nodal involvement, grading, estrogen and progesterone receptor status indicated no correlation between induction of amenorrhea and a significant prolongation of overall and disease-free survival. Multivariate analyses confirmed that young age at diagnosis, increasing number of infiltrated nodes, negative progesterone receptor status and grade 3 tumors are associated with a worse prognosis. Our results suggest that no benefit is expected in women with drug induced amenorrhea after CMF adjuvant treatment.

The relationship between tumour proliferative activity, evaluated by thymidine labelling index (TLI), clinicopathological variables and clinical outcome, was analysed in a series of 64 chemotherapy-resistant, ovarian cancer patients. The median TLI of 4.6% (range 0.01-45.7) was used as the cut-off to discriminate rapidly from slowly proliferating tumours. Univariate analyses showed a significant advantage in survival for patients with TLI less than or equal to 4.6 (P = 0.0004), ECOG performance status less than or equal to 1 (P = 0.0001) and residual disease after primary surgery less than or equal to 2 cm (P = 0.019). Multivariate analysis demonstrated that performance status was the only independent prognostic variable, although TLI was the last covariate removed from the Cox's regression model.

Lonidamine belongs to a new class of antineoplastics agents, since it does interfere with cell energy processes. When administered as single agent in metastatic breast cancer, it produces moderate therapeutic effects. The pattern of toxicity includes myalgias, asthenia, testicular pain, and gastrointestinal discomfort. No myelosuppression was demonstrated in phase I-II studies. Since the peculiar mechanism of action and side effects are not overlapping with those of standard chemotherapeutic agents, combination of lonidamine with chemotherapy is currently under investigation in advanced breast cancer. Moreover, the potentiation of radiotherapy by lonidamine could be of interest in palliating symptomatic lesions from breast cancer.

Patients presenting with clinical features of locally advanced, non-metastatic breast cancer (T3–T4, N2–N3, M0) have a poor prognosis. After loco-regional treatment by radiation therapy and/or surgery the recurrence rate is high and rapid with median survival less than three years [1–3]. Although not evaluated in randomized clinical trials, there is evidence that the combination of local and systemic treatment has produced a substantial improvement, as compared to historical controls. Five-year survivals in excess of 50 % have been reported from studies in which chemotherapy is used before and after local treatment [4]. In the present report, we review our experience with a multidisciplinary therapeutic approach in patients with locally advanced breast cancer; moreover we have analyzed the relevance of some pretreatment and treatment-related variables in affecting the results in terms of disease-free survival and overall survival.

In 100 ovarian cancer patients serum CA-125 was monitored during treatment and follow-up to verify the prognostic value of its pre-surgery marker level and the usefulness of the test for disease monitoring. A low pre-operative CA-125 was not associated with improved survival or progression-free survival. A significant survival advantage was evident for patients in whom the marker had decreased during treatment, compared to patients in whom the antigen remained unchanged or increased. In 40 patients CA-125 was measured before second look laparotomy: the marker was negative in 100% of patients in, pathological complete response and in 53.5% of patients with residual disease at second look. A marker increase was evident in 32 of 41 patients with either progressive or recurrent disease, and in 17 patients the CA-125 increase was documented from 1 to 9 months before clinical evidence of progression. The pre-operative level of CA-125 did not appear to be of prognostic value. However, the monitoring of CA-125 during treatment and follow-up can provide a reliable method of assessing response and prognosis. CA-125 monitoring is particularly useful for early detection of recurrence.

Fifty-seven patients who had progressed during or relapsed after randomized first-line combination chemotherapy containing cisplatin or carboplatin were entered into a crossover study in which the analog not previously assigned was administered alone as salvage treatment. Carboplatin and cisplatin were administered at doses of 400 and 100 mg/m 2 , respectively, every 28 days. Among the 24 patients enrolled in the cisplatin arm, 6 (25%) objective responses (ORs) (3 complete, 3 partial) were observed, whereas 3 partial responses were obtained in the 33 carboplatin-treated patient (9%). Analysis of results, according to response to first-line chemotherapy, demonstrated that the patients who progressed were sensitive only to cisplatin second-line treatment (OR: 312), with no responders among carboplatin-treated patients (OR: 011). All patients were treated on an outpatient basis and therapy-related toxic effects were mild, consisting chiefly of myelosuppression, and more frequent in the carboplatin group. In our opinion, carboplatin 400 mg/m 2 per cycle is scarcely effective in patients with refractory or relapsed ovarian cancer pretreated with cisplatin regimens, whereas cisplatin 100 mg/m 2 per cycle appears to be an effective salvage therapy even in patients not responding to carboplatin. The dose of carboplatin should be further escalated especially in refractory patients.

A series of 129 patients with International Federation of Gynecology and Obstetrics (FIGO) stage III-IV ovarian cancer, were evaluated with ultrasound examination and second look surgery. Results of both modalities were correlated in order to assess the reliability of ultrasound in detecting residual disease. After six cycles of chemotherapy, ultrasound was negative in 94 patients and positive in 35 patients. At second look, 57 patients were in complete pathologic remission, 16 had microscopic residual disease, 23 had macroscopic disease less than 2 cm, and 33 had macroscopic disease greater than 2 cm. Correlating ultrasonography and laparotomy, high correlations were seen in patients with no residual disease (92.2%); on the other hand, ultrasound examinations exhibited poor sensitivity and specificity in patients with microscopic disease (6.2%) and residual disease less than 2 cm (8.6%). Using ultrasound discrimination among patients with no residual disease, microscopic disease, or macroscopic disease less than 2 cm does not appear possible. Our suggestion is that ultrasound is not able to replace second look laparotomy in the detection of minimal residual disease in ovarian cancer patients.