Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Más filtros










Intervalo de año de publicación
1.
Rev. mex. ing. bioméd ; 42(1): e1110, Jan.-Apr. 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1156801

RESUMEN

ABSTRACT A new coronavirus denominated first 2019-nCoV and later SARS-CoV-2 was found in Wuhan, China in December of 2019. This paper compares three mathematical methods: nonlinear regression, SIR, and SEIR epidemic models, to track the covid-19 disease in nine countries affected by the SARS-CoV-2 virus, to help epidemiologists to know the disease trajectory, considering initial data in the pandemic, mainly 100 days from the beginning. To evaluate the results obtained with the three methods one-way ANOVA is applied. The average of predicted infected cases with SARS-CoV-2, obtained with the mentioned methods was: for United States of America 1,098,508, followed by Spain with 226,721, Italy with 202,953, France with 183,897 United Kingdom with 182,190, Germany with 159,407, Canada with 58,696, Mexico with 50,366 and Argentina with 4,860 in average. The one-way ANOVA does not show a significant difference among the results of the projected infected cases by SARS-CoV-2, using nonlinear regression, SIR, and SEIR epidemic methods. The above could mean that initially any method can be used to model the pandemic course.


RESUMEN Un nuevo coronavirus denominado primero 2019-nCoV y más tarde SARS-CoV-2 fue encontrado en Wuhan, China en diciembre de 2019. El objetivo de este trabajo es comparar tres métodos matemáticos: regresión no lineal, modelos epidemiológicos SIR y SEIR, para rastrear la enfermedad del COVID-19 en nueve países infectados por el virus SARS-CoV-2, con el propósito de ayudar al epidemiólogo a conocer el curso de la pandemia, considerando principalmente sus primeros 100 días. Para evaluar los resultados obtenidos de la aplicación de los tres métodos, se aplicó ANOVA de una vía. El número promedio de casos infectados con SARS-CoV-2, obtenidos con los tres métodos descritos son: para Estados Unidos 1,098,508, seguido de España con 226,721, Italia con 202,953, Francia con 183,897 Reino Unido con 182,190, Alemania con 159,407, Canadá con 58,696, México con 50,366 y Argentina con 4,860 en promedio. El ANOVA de una vía no muestra diferencias significativas entre los resultados de los casos infectados proyectados por SARS-CoV-2, utilizando la regresión no lineal y los métodos SIR and SEIR. Lo anterior podría señalar que cualquiera de los tres métodos estudiados puede modelar el curso de la pandemia en las condiciones descritas para cada uno.

2.
Cell Death Differ ; 22(9): 1551-60, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25744022

RESUMEN

To grant faithful chromosome segregation, the spindle assembly checkpoint (SAC) delays mitosis exit until mitotic spindle assembly. An exceedingly prolonged mitosis, however, promotes cell death and by this means antimicrotubule cancer drugs (AMCDs), that impair spindle assembly, are believed to kill cancer cells. Despite malformed spindles, cancer cells can, however, slip through SAC, exit mitosis prematurely and resist killing. We show here that the Fcp1 phosphatase and Wee1, the cyclin B-dependent kinase (cdk) 1 inhibitory kinase, play a role for this slippage/resistance mechanism. During AMCD-induced prolonged mitosis, Fcp1-dependent Wee1 reactivation lowered cdk1 activity, weakening SAC-dependent mitotic arrest and leading to mitosis exit and survival. Conversely, genetic or chemical Wee1 inhibition strengthened the SAC, further extended mitosis, reduced antiapoptotic protein Mcl-1 to a minimum and potentiated killing in several, AMCD-treated cancer cell lines and primary human adult lymphoblastic leukemia cells. Thus, the Fcp1-Wee1-Cdk1 (FWC) axis affects SAC robustness and AMCDs sensitivity.


Asunto(s)
Antineoplásicos/farmacología , Proteínas de Ciclo Celular/metabolismo , Quinasas Ciclina-Dependientes/metabolismo , Microtúbulos/efectos de los fármacos , Proteínas Nucleares/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Huso Acromático/efectos de los fármacos , Huso Acromático/metabolismo , Adulto , Proteína Quinasa CDC2 , Línea Celular Tumoral , Células HeLa , Humanos , Puntos de Control de la Fase M del Ciclo Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Adulto Joven
3.
J Hazard Mater ; 161(2-3): 769-74, 2009 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-18499342

RESUMEN

The degradation of two immobilized dyes by Klebsiella sp. UAP-b5 was studied. In batch experiments, the azo dyestuffs Basic Blue 41 and Reactive Black 5 were immobilized onto corn cobs by adsorption, and the adsorption process was characterized by a pseudo-second-order kinetic equation. Klebsiella sp. UAP-b5 was previously isolated from the corn waste and shown to decolorize these dyes in liquid systems. Here, we demonstrate anaerobic decolorization and reductive biodegradation of these dyes by means of spectrophotometry, HPLC, and IR spectroscopy of the solid waste and desorption solutions. We also demonstrate adsorption of compounds that resemble known degradation products.


Asunto(s)
Biodegradación Ambiental , Colorantes/química , Klebsiella/metabolismo , Zea mays/metabolismo , Adsorción , Cromatografía Líquida de Alta Presión , Colorantes/metabolismo , Cinética , Modelos Químicos , Modelos Teóricos , Eliminación de Residuos , Espectrofotometría Infrarroja/métodos , Espectrofotometría Ultravioleta/métodos , Temperatura , Purificación del Agua/métodos
4.
J Exp Clin Cancer Res ; 26(2): 291-2, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17725112

RESUMEN

In this manuscript for the first time we describe the concomitant diagnosis of primary renal non-Hodgkin lymphoma (PRL) and of a papillary urothelial cancer in a patient with megaloblastic anemia. PRL is a rare disease, since the kidney is one of the extranodal organs usually not containing lymphoid tissue. The disease usually affects adults with an average age of 60 years and slight male preponderance. Flank pain is the most common presenting symptom and different histologies have been reported. A review of literature indicated that simultaneous diagnosis of PRL and papillary urothelial carcinoma of the urether, makes our case unique. The early diagnosis of both diseases allowed the eradication of the two neoplasms by nephro-ureterecthomy and by performing subsequent systemic chemotherapy.


Asunto(s)
Carcinoma Papilar/diagnóstico por imagen , Neoplasias Renales/diagnóstico por imagen , Linfoma no Hodgkin/diagnóstico por imagen , Neoplasias Ureterales/diagnóstico por imagen , Carcinoma Papilar/complicaciones , Carcinoma Papilar/patología , Diagnóstico Precoz , Femenino , Humanos , Neoplasias Renales/complicaciones , Neoplasias Renales/patología , Linfoma no Hodgkin/complicaciones , Linfoma no Hodgkin/patología , Tomografía Computarizada por Rayos X , Neoplasias Ureterales/complicaciones , Neoplasias Ureterales/patología
5.
J Pharm Biomed Anal ; 38(2): 239-49, 2005 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-15925214

RESUMEN

An NP-HPLC method both with diode-array (DAD) and electrochemical detection (ED) was developed and validated for the determination of quercetin and kaempferol, the principal active constituents in phytopharmaceuticals of Ginkgo Biloba. Calculated retention of the two flavonoids was contrasted with experimental values in five different reversed phase columns for methanol-water, acetonitrile-water, THF-water and dioxane-hexane binary mixtures as mobile phases. The capacity factor k, selectivity alpha and asymmetry factor F were evaluated and compared in DAD-RP-HPLC, DAD-NP-HPLC, ED-RP-HPLC and ED-NP-HPLC. The methods were used for the quantitative analysis of acid hydrolyzed extracts of tablet phytopharmaceuticals. Calibration curves were linear within the range 10 and 40 microg ml(-1) for the DAD and 10-270 microg ml(-1) for the ED, whereby limits of detection ranged from 0.5 microg ml(-1) (quercetin) to 0.1 microg ml(-1) (kaempferol). The electrochemical method based on differential pulse voltammetry (DPV) with a C-PVC electrode resolved the quercetin and kaempferol peaks and exhibited a two orders higher sensitivity in comparison with a carbon fiber electrode. DPV calibration curves were linear within the range 96-300 microg ml(-1) for quercetin and 68-960 microg ml(-1) for kaempferol. The respective oxidation peaks appeared at 462 and 518+/-2 mV and were used in the direct determination of quercetin in extracts of commercial phytopharmaceuticals.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Electroquímica/métodos , Quempferoles/análisis , Extractos Vegetales/análisis , Quercetina/análisis , Estabilidad de Medicamentos , Ginkgo biloba/química , Preparaciones Farmacéuticas/análisis , Extractos Vegetales/química , Reproducibilidad de los Resultados , Comprimidos
6.
Leukemia ; 15(10): 1641-9, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11587224

RESUMEN

Two novel IL2-dependent cell lines, DERL-2 and DERL-7, were established from a patient with hepatosplenic gammadelta T cell lymphoma. This patient presented, at diagnosis, two discrete populations of CD56+ cells, one TCRgammadelta+, the second lacking T cell-restricted antigens. The cell lines derived displayed features corresponding to the two cellular components of the disease: DERL-2 was CD56+/CD3+/TcRgammadelta+ while DERL-7 was CD56+/CD3-/TcRgammadelta-. Along with CD56, the two cell lines shared the expression of CD7, CD2, CD158b and CD117. Karyotype analysis showed that both cell lines were near-diploid, with iso-7q and loss of one chromosome 10. In addition, DERL-2 showed 5q+ in all metaphases analyzed, while DERL-7 revealed loss of one chromosome 4. Genotypically, both cell lines shared the same STR pattern at nine loci and demonstrated an identical rearranged pattern of the T cell receptor genes beta, gamma and delta, with respect to the original tumor cells. These data indicated that both cell lines and the original neoplastic populations were T cell-derived and arose from a common ancestor. Among a large panel of cytokines tested, only SCF was able to substitute IL2 in supporting cell proliferation. Moreover, SCF and IL2 acted synergistically, dramatically enhancing cell growth. These cell lines may represent a model to further analyze the overlap area between T and NK cell malignancies, and may provide new information about the synergistic action of IL2 and SCF on normal and neoplastic T/NK cells.


Asunto(s)
Linfoma no Hodgkin/inmunología , Linfoma no Hodgkin/patología , Células Tumorales Cultivadas/citología , Adulto , Complejo CD3/análisis , Antígeno CD56/análisis , División Celular/efectos de los fármacos , Análisis Citogenético , Sinergismo Farmacológico , Reordenamiento Génico de la Cadena beta de los Receptores de Antígenos de los Linfocitos T/genética , Genotipo , Humanos , Inmunofenotipificación , Interleucina-2/farmacología , Masculino , Receptores de Antígenos de Linfocitos T gamma-delta/análisis , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Factor de Células Madre/farmacología
7.
Haematologica ; 85(5): 496-501, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10800166

RESUMEN

BACKGROUND AND OBJECTIVE: Large granular lymphocytes derive from two major lineages: one expressing the CD3 surface antigen (T-lymphocytes), and the other lacking this marker (NK-cells). Although developmental overlaps between natural killer cells and T-cells have been described, malignancies derived from these two cell types are considered as distinct lymphoid disorders. DESIGN AND METHODS: We report the case of a 30-year old man affected by a lymphoma/leukemia syndrome presenting with hepatosplenic lymphoma which rapidly transformed into aggressive NK-leukemia. Extensive flow cytometry studies and molecular analysis were repeated during the course of the disease, and showed an unexpected changing pattern. RESULTS: At diagnosis, flow cytometry analysis showed the co-existence of two cell populations, one CD56(+), CD3(+), TcRgd(+), and the other CD56(+), CD3(-) and TcRgd(-). Molecular analysis showed that the TcR genes had the same clonally rearranged pattern involving b, g and d genes in both populations. At disease relapse and during the terminal refractory phase, only CD3(-) cells were present. INTERPRETATION AND CONCLUSIONS: This is an unusual case of CD56(+) aggressive lymphoma/leukemia characterized by the clonal expansion of two phenotypically different cell populations, variably balanced during the course of the disease. The presence of the same TcR genomic rearrangement suggests the origin from a common progenitor able to differentiate along both T- and NK-pathways.


Asunto(s)
Antígeno CD56/sangre , Inmunofenotipificación , Leucemia/inmunología , Linfoma/inmunología , Adulto , Complejo CD3/sangre , Células Clonales , Análisis Citogenético , Progresión de la Enfermedad , Humanos , Células Asesinas Naturales/citología , Células Asesinas Naturales/inmunología , Leucemia/sangre , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/inmunología , Linfoma/sangre , Masculino , Receptores de Antígenos de Linfocitos T gamma-delta/sangre , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Neoplasias del Bazo/sangre , Neoplasias del Bazo/inmunología , Linfocitos T/citología , Linfocitos T/inmunología
8.
Cancer ; 88(1): 75-8, 2000 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-10618608

RESUMEN

BACKGROUND: CA 125 is a tumor marker used for the diagnosis and monitoring of ovarian carcinoma. This marker also has been found to be increased in patients with serosal effusion derived from nonneoplastic inflammatory disease and in a few instances of advanced non-Hodgkin lymphoma with serosal involvement. METHODS: CA 125 levels were tested in the serum of 15 patients with acute myeloblastic leukemia (AML) at the time of diagnosis and in 3 patients with advanced leukemia with serosal involvement. In two patients with elevated serum CA 125 levels, a CA 125 assay was performed on leukemic cells and on the supernatant fluid of short term liquid culture. RESULTS: Increased serum CA 125 was found in the three patients with acute leukemia with extramedullary localization and serosal effusion, whereas it was normal in 15 AML patients tested at the time of diagnosis. CA 125 was not detectable in leukemic cell extracts nor in the supernatant fluid of primary cultures. CONCLUSIONS: These results indicate that leukemic cells were unable to produce CA 125 and suggest that its elevation in the serum is likely due to a serosal inflammatory reaction caused by the leukemic infiltration.


Asunto(s)
Biomarcadores de Tumor/sangre , Antígeno Ca-125/sangre , Leucemia Mieloide Aguda/inmunología , Adulto , Femenino , Humanos , Inflamación/inmunología , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Membrana Serosa/patología
10.
Tissue Antigens ; 52(1): 1-8, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9714468

RESUMEN

CD66c is a surface (and intracellular) molecule bound to the membrane by a glycosyl-phosphatidylinositol anchor. While its expression on peripheral granulocytes is well recognized, less is known about its distribution in early steps of normal and neoplastic hematopoiesis. We analyzed by flow cytometry cell surface expression of CD66c on bone marrow cells from 4 healthy subjects and on bone marrow or peripheral blood cells from 127 patients with newly diagnosed hematologic malignancies: 70 de novo acute myeloid leukemias (AML), 6 refractory anemias with excess of blasts in transformation, 3 myeloid and 3 lymphoid blastic phases of chronic myelogenous leukemia, 33 B-lineage and 6 T-lineage acute lymphoblastic leukemias (B- and T-ALL), and 3 B-cell and 3 T-cell non-Hodgkin's lymphomas in the leukemic phase. We found that in normal bone marrow CD66c expression was myeloid restricted, reaching its highest level on promyelocytes. As for de novo AML, slight expression of CD66c was found on 6/25 (24%) AML-M4 and only occasionally in other subgroups. In 9 out of 10 cases of acute promyelocytic leukemia, CD66c was totally absent, but antigen expression was easily detectable following in vitro exposure to all-trans retinoic acid. Among lymphoid malignancies, CD10+ early-B-ALL consistently expressed the molecule (20/23 cases, or 87%) whereas both CD10- early-B ALL and SmIg+ B-ALL completely lacked it. Finally, dual staining with CD66c and CD10 proved to be a suitable tool for distinguishing even low percentages of residual leukemic cells (CD10+/CD66c+) from normal regenerating early-B cells (CD10+/CD66c ) in CD10+ early-B-ALL induced into remission.


Asunto(s)
Antígenos de Diferenciación Mielomonocítica/inmunología , Antígenos de Neoplasias , Células de la Médula Ósea/inmunología , Moléculas de Adhesión Celular , Leucemia de Células B/inmunología , Glicoproteínas de Membrana/inmunología , Neprilisina/inmunología , Antígenos CD , Separación Celular , Citometría de Flujo , Proteínas Ligadas a GPI , Humanos , Inmunofenotipificación , Leucemia de Células T/inmunología , Leucopoyesis
11.
Photodermatol Photoimmunol Photomed ; 12(5): 200-3, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9112278

RESUMEN

The in vitro sensitivity of human hematopoietic progenitors to PUVA, 8-MOP and UVA alone was investigated. 8-MOP alone at final concentrations of 150, 200, 600 and 1,000 ng/ml did not modify colony growth of circulating and bone marrow erythroid (BFU-E), myeloid (CFU-GM) and immature (CFU-GEMM) hematopoietic progenitors obtained from normal controls. The exposure of the same progenitors to increasing doses of UVA, up to 12 J/cm2, progressively decreased hematopoietic colony growth (with estimated 50% inhibition occurring at about 5 J/cm2). In vitro PUVA treatment (8-MOP 200 ng/ml followed by UVA 5 J/cm2) caused 90% growth inhibition of circulating and bone marrow hematopoietic progenitors. In addition, the treatment completely inhibited the formation of spontaneous erythroid colonies, obtained from 5 polycythemic patients, that are considered to be a marker of this neoplastic disease. PUVA cytotoxicity was assessed by the colorimetric MTT assay. The percentage of cell death after PUVA exposure was 29 +/- 10% for both peripheral and bone marrow mononuclear cells. Our findings indicate that 8-MOP alone is not toxic to hematopoietic progenitors whereas UVA treatment determines in vitro a dose-dependent inhibition of the clonogenic capacity of normal hematopoietic cells. PUVA treatment enhances this effect, causing a quite complete inhibition of hematopoietic progenitors colony formation from normal donors and spontaneous BFU-E colony formation from polycythemic patients.


Asunto(s)
Células Madre Hematopoyéticas/fisiología , Terapia PUVA , Supervivencia Celular/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Precursoras Eritroides/metabolismo , Eritropoyetina/metabolismo , Hematopoyesis/efectos de los fármacos , Hematopoyesis/efectos de la radiación , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Policitemia/fisiopatología
13.
Ann Parasitol Hum Comp ; 58(5): 413-22, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6660794

RESUMEN

After an investigation carried out with samples from several sewage sludges from the town of Pavia (Italy) the AA. report the isolation of two new strains of Entamoeba moshkovskii. The usefulness and reliability of two methods, i.e. growth in hypotonic media and the thermoresistance tests in vitro for the biological typing of this species are analyzed and discussed. Both methods had already proven useful to characterize the Laredo-type strains of E. histolytica too, as reported by other AA.


Asunto(s)
Entamoeba/aislamiento & purificación , Animales , Entamoeba/anatomía & histología , Entamoeba/fisiología , Humanos , Italia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA