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3.
Bone Marrow Transplant ; 50(11): 1432-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26168069

RESUMEN

Although hemorrhagic cystitis (HC) is a common complication of allogeneic hematopoietic cell transplantation (alloHCT), its risk factors and effects on survival are not well known. We evaluated HC in a large cohort (n=1321, 2003-2012) receiving alloHCT from all graft sources, including umbilical cord blood (UCB). We compared HC patients with non-HC (control) patients and examined clinical variables at HC onset and resolution. Of these 1321 patients, 219 (16.6%) developed HC at a median of 22 days after alloHCT. BK viruria was detected in 90% of 109 tested HC patients. Median duration of HC was 27 days. At the time of HC diagnosis, acute GVHD, fever, severe thrombocytopenia and steroid use were more frequent than at the time of HC resolution. In univariate analysis, male sex, age <20 years, myeloablative conditioning with cyclophosphamide and acute GVHD were associated with HC. In multivariate analysis, HC was significantly more common in males and HLA-mismatched UCB graft recipients. Severe grade HC (grade III-IV) was associated with increased treatment-related mortality but not with overall survival at 1 year. HC remains hazardous and therefore better prophylaxis, and early interventions to limit its severity are still needed.


Asunto(s)
Ciclofosfamida/efectos adversos , Cistitis/etiología , Enfermedad Injerto contra Huésped/complicaciones , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Hemorragia/etiología , Acondicionamiento Pretrasplante/efectos adversos , Adolescente , Adulto , Factores de Edad , Aloinjertos , Niño , Preescolar , Estudios de Cohortes , Ciclofosfamida/uso terapéutico , Cistitis/inducido químicamente , Cistitis/epidemiología , Infecciones por Citomegalovirus/complicaciones , Femenino , Enfermedad Injerto contra Huésped/epidemiología , Trasplante de Células Madre Hematopoyéticas/métodos , Hemorragia/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Sexuales , Análisis de Supervivencia , Trombocitopenia/epidemiología , Trombocitopenia/etiología , Activación Viral , Adulto Joven
4.
Cancer Lett ; 113(1-2): 131-9, 1997 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-9065812

RESUMEN

Given the important role of the estrogen receptor (ER) in the development and physiology of the breast, it is essential to delineate the mechanisms responsible for its failed expression in some breast tumors. We have cloned and sequenced a portion of the ER upstream regulatory region from the ER-positive MCF-7 and the ER-negative MDA-MB-231 breast cancer cell lines to determine if sequence alterations in this region account for the ER-negative phenotype of some tumors. From this, we identified a number of variations between the sequences, two of which were determined to be associated with a 50% decrease in CAT activity.


Asunto(s)
Neoplasias de la Mama/genética , Receptores de Estrógenos/genética , Secuencia de Bases , Neoplasias de la Mama/enzimología , Cloranfenicol O-Acetiltransferasa/genética , Cloranfenicol O-Acetiltransferasa/metabolismo , Clonación Molecular , Femenino , Variación Genética , Humanos , Leucocitos , Datos de Secuencia Molecular , Secuencias Reguladoras de Ácidos Nucleicos , Homología de Secuencia de Ácido Nucleico , Células Tumorales Cultivadas
5.
Mol Cell Endocrinol ; 158(1-2): 25-36, 1999 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-10630402

RESUMEN

The estrogen receptor (ER) serves as a diagnostic marker for the treatment of breast cancer. Patients with ER-positive breast tumors are likely to respond to hormonal therapies, while ER-negative breast cancers are resistant to endocrine therapies. Most ER-negative tumors do not express detectable levels of ER transcript, highlighting the importance of transcriptional regulation. A novel regulatory element which resembles a steroid hormone response element has been identified in the 5'-flanking region of the human ER gene. We observed 3- to 5-fold higher specific binding to this element in nuclear extracts from ER-expressing MCF-7 breast cancer cells compared to ER-negative MDA-MB-231 breast tumor cells. We termed the factor(s) which bind to this cis-element estrogen receptor upstream binding factor-1 (ERUBF-1). In transient transfection assays in MCF-7 cells, the ERUBF-1 binding site elicited a 20-fold increase in luciferase activity over the ER P1, promoter. This enhancer element was significantly more active in the ER-positive MCF-7 cell line compared to the ER-negative MDA-MB-231 cell line. These data indicate that ERUBF-1 plays an important role in the transcriptional regulation of the ER gene in breast cancer.


Asunto(s)
Elementos de Facilitación Genéticos , Receptores de Estrógenos/genética , Secuencia de Bases , Western Blotting , Neoplasias de la Mama , Huella de ADN , ADN de Neoplasias/análisis , Femenino , Genes Reporteros/genética , Humanos , Luciferasas/genética , Luciferasas/metabolismo , Datos de Secuencia Molecular , Neoplasias Hormono-Dependientes , Unión Proteica , Transfección , Células Tumorales Cultivadas
6.
Pharmacol Biochem Behav ; 68(3): 379-87, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11325389

RESUMEN

Methionine enkephalin (Met-enkephalin) functions as an endogenous anticonvulsant. Peptide transport system-1 (PTS-1) is an important regulator of Met-enkephalin levels in brain and transports the peptide from brain to blood. In outbred mice, alcohol dependence is associated with decreased PTS-1 activity and increased levels of Met-enkephalin. In contrast, alcohol withdrawal is associated with recovery of PTS-1 activity, decreased levels of Met-enkephalin, and seizures. In this study, we examined the PTS-1/Met-enkephalin system in two replicates of withdrawal seizure-resistant (WSR) and withdrawal seizure-prone (WSP) mouse lines. We measured levels of preproenkephalin (PPE) mRNA and Met-enkephalin peptide in brain and the activity of PTS-1 during alcohol-naive, -dependent, and -withdrawal states. In alcohol-naive animals, Met-enkephalin levels were higher in WSP than in WSR mice. In alcohol-withdrawal animals, Met-enkephalin levels remained elevated in WSP mice, whereas they increased in WSR mice. Peptide levels were unrelated to levels of PPE mRNA or activity of PTS-1. Factorial analysis showed that proneness to seizures was genetically linked to Met-enkephalin levels in alcohol-naive, -dependent, and -withdrawing mice but not to mRNA levels or PTS-1 activity. Overall, these results may be explained by resistance to enkephalin in WSP mice and suggest that the dysregulation of the PTS-1/Met-enkephalin system contributes to susceptibility to seizures in WSP mice.


Asunto(s)
Depresores del Sistema Nervioso Central , Encefalinas/fisiología , Etanol , Hormona Inhibidora de la Liberación de MSH/análogos & derivados , Convulsiones/fisiopatología , Síndrome de Abstinencia a Sustancias/fisiopatología , Aluminio/farmacología , Animales , Química Encefálica/efectos de los fármacos , Química Encefálica/fisiología , Digoxigenina/metabolismo , Encefalina Metionina/metabolismo , Encefalinas/biosíntesis , Encefalinas/genética , Femenino , Semivida , Hormona Inhibidora de la Liberación de MSH/metabolismo , Ratones , Ratones Endogámicos , Neuropéptidos/análisis , Precursores de Proteínas/biosíntesis , Precursores de Proteínas/genética , ARN Mensajero/biosíntesis , Radioinmunoensayo , Convulsiones/genética
7.
Ann. intern. med ; 162(3)Feb . 2015. tab
Artículo en Inglés | BIGG | ID: biblio-965845

RESUMEN

BACKGROUND: The AABB (formerly, the American Association of Blood Banks) developed this guideline on appropriate use of platelet transfusion in adult patients. METHODS: These guidelines are based on a systematic review of randomized, clinical trials and observational studies (1900 to September 2014) that reported clinical outcomes on patients receiving prophylactic or therapeutic platelet transfusions. An expert panel reviewed the data and developed recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. RECOMMENDATION 1: The AABB recommends that platelets should be transfused prophylactically to reduce the risk for spontaneous bleeding in hospitalized adult patients with therapy-induced hypoproliferative thrombocytopenia. The AABB recommends transfusing hospitalized adult patients with a platelet count of 10 × 109 cells/L or less to reduce the risk for spontaneous bleeding. The AABB recommends transfusing up to a single apheresis unit or equivalent. Greater doses are not more effective, and lower doses equal to one half of a standard apheresis unit are equally effective. (Grade: strong recommendation; moderate-quality evidence). RECOMMENDATION 2: The AABB suggests prophylactic platelet transfusion for patients having elective central venous catheter placement with a platelet count less than 20 × 109 cells/L. (Grade: weak recommendation; low-quality evidence). RECOMMENDATION 3: The AABB suggests prophylactic platelet transfusion for patients having elective diagnostic lumbar puncture with a platelet count less than 50 × 109 cells/L. (Grade: weak recommendation; very-low-quality evidence). RECOMMENDATION 4: The AABB suggests prophylactic platelet transfusion for patients having major elective nonneuraxial surgery with a platelet count less than 50 × 109 cells/L. (Grade: weak recommendation; very-low-quality evidence). RECOMMENDATION 5: The AABB recommends against routine prophylactic platelet transfusion for patients who are nonthrombocytopenic and have cardiac surgery with cardiopulmonary bypass. The AABB suggests platelet transfusion for patients having bypass who exhibit perioperative bleeding with thrombocytopenia and/or evidence of platelet dysfunction. (Grade: weak recommendation; very-low-quality evidence). RECOMMENDATION 6: The AABB cannot recommend for or against platelet transfusion for patients receiving antiplatelet therapy who have intracranial hemorrhage (traumatic or spontaneous). (Grade: uncertain recommendation; very-low-quality evidence).(AU)


Asunto(s)
Humanos , Adulto , Punción Espinal , Procedimientos Quirúrgicos Electivos , Transfusión de Plaquetas , Hemorragias Intracraneales , Circulación Extracorporea , Catéteres Venosos Centrales , Trombocitopenia
8.
Parasitol Today ; 13(6): 231-5, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15275076

RESUMEN

Parasites of the family Trypanosomatidae have an absolute requirement for purines, yet lack the intracellular machinery to synthesize their own purine ring de novo. As a result, the enzymes devoted to the transport and metabolism of purines are extremely important to the parasite. Here, Claudia Cohn and Michael Gottlieb emphasize the value of understanding purine salvage for the development of trypanocidal drugs, and discuss the putative transporters devoted to purine uptake.

9.
J Protozool ; 37(6): 456-64, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1964968

RESUMEN

Variants of a cloned laboratory stock of the trypanosomatid parasite Crithidia luciliae have been distinguished from "parental type" organisms. These variants accumulated spontaneously over time as the protozoan was maintained by continuous passage in a chemically defined medium. Cloned lines of these variants have been isolated by plating on nutrient agar and partially characterized on the basis of their growth characteristics in culture, their colony and cellular morphology as well as their surface protein expression. One cloned line consisted of motile, flagellated forms which, unlike "parental type" organisms, did not adhere to the surface of culture flasks. Another cloned line was composed of non-adherent, nonmotile, amastigote-like forms which were further distinguished from "parental type" cells by virtue of their constitutive expression, in nutrient-replete medium, of high levels of a surface membrane associated 3'-nucleotidase/nuclease (3'-N'ase) activity. Both the motile, flagellated and amastigote-like variants, like the "parental type" organisms, exhibited elevated levels of the 3'-N'ase activity upon exposure to purine starvation conditions. The variants described are of potential importance in elucidating the mechanism of induction of the highly regulated 3'-N'ase activity as well as for understanding the cytoskeletal systems and the surface properties of these protozoa.


Asunto(s)
Crithidia/aislamiento & purificación , Animales , Autorradiografía , Células Clonales , Crithidia/fisiología , Crithidia/ultraestructura , Electroforesis en Gel de Poliacrilamida , Variación Genética , Proteínas de la Membrana/análisis , Microscopía Electrónica de Rastreo , Nucleotidasas/metabolismo , Purinas/metabolismo , Pase Seriado
10.
Br J Cancer ; 77(12): 2129-37, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9649124

RESUMEN

Neoplastic events are marked by uncontrolled cell proliferation. One major focus of cancer research has been to identify treatments that reduce or inhibit cell growth. Over the years, various compounds, both naturally occurring and chemically synthesized, have been used to inhibit neoplastic cell proliferation. Two such oncostatic agents, melatonin and retinoic acid, have been shown to suppress the growth of hormone-responsive breast cancer. Currently, separate clinical protocols exist for the administration of retinoids and melatonin as adjuvant therapies for cancer. Using the oestrogen receptor (ER)-positive MCF-7 human breast tumour cell line, our laboratory has studied the effects of a sequential treatment regimen of melatonin followed by all-trans retinoic acid (atRA) on breast tumour cell proliferation in vitro. Incubation of hormonally responsive MCF-7 and T47D cells with melatonin (10(-9) M) followed 24 h later by atRA (10(-9) M) resulted in the complete cessation of cell growth as well as a reduction in the number of cells to below the initial plating density. This cytocidal effect is in contrast to the growth-suppressive effects seen with either hormone alone. This regimen of melatonin followed by atRA induced cytocidal effects on MCF-7 cells by activating pathways leading to apoptosis (programmed cell death) as evidenced by decreased ER and Bcl-2 and increased Bax and transforming growth factor beta 1 (TGF-beta1) expression. Apoptosis was reflected morphologically by an increase in the number of lysosomal bodies and perinuclear chromatin condensation, cytoplasmic blebbing and the presence of apoptotic bodies. The apoptotic effect of this sequential treatment with melatonin and atRA appears to be both cell and regimen specific as (a) ER-negative MDA-MB-231 and BT-20 breast tumour cells were unaffected, and (b) the simultaneous administration of melatonin and atRA was not associated with apoptosis in any of the breast cancer cell lines studied. Taken together, the results suggest that use of an appropriate regimen of melatonin and atRA should be considered for preclinical and clinical evaluation against ER-positive human breast cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Northern Blotting , Western Blotting , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , ADN de Neoplasias/análisis , ADN de Neoplasias/aislamiento & purificación , Esquema de Medicación , Electroforesis , Humanos , Melatonina/administración & dosificación , Neoplasias Hormono-Dependientes/metabolismo , Neoplasias Hormono-Dependientes/patología , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Receptores de Estrógenos/biosíntesis , Receptores de Estrógenos/efectos de los fármacos , Receptores de Estrógenos/metabolismo , Factor de Crecimiento Transformador beta/biosíntesis , Factor de Crecimiento Transformador beta/metabolismo , Tretinoina/administración & dosificación , Células Tumorales Cultivadas , Proteína X Asociada a bcl-2
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