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1.
Am J Transplant ; 15(10): 2665-73, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25988622

RESUMEN

We examined the associations of Epstein-Barr virus (EBV) status with characteristics and outcomes of posttransplantation lymphoproliferative disorder (PTLD) by studying 176 adult solid organ transplant recipients diagnosed with PTLD between 1990 and 2013 (58 [33%] EBV-negative; 118 [67%] EBV-positive). The proportion of EBV-negative cases increased over time from 10% (1990-1995) to 48% (2008-2013) (p < 0.001). EBV-negative PTLD had distinct characteristics (monomorphic histology, longer latency) though high-risk features (advanced stage, older age, high lactate dehydrogenase, central nervous system involvement) were not more common compared to EBV-positive PTLD. In multivariable analysis, EBV negativity was not significantly associated with worse response to initial therapy (adjusted odds ratio, 0.84; p = 0.75). The likelihood of achieving a complete remission (CR) was not significantly different for EBV-negative versus EBV-positive PTLD including when therapy was reduction of immunosuppression alone (35% vs. 43%, respectively, p = 0.60) or rituximab (43% vs. 47%, p = 1.0). EBV negativity was also not associated with worse overall survival (adjusted hazard ratio, 0.91; p = 0.71). Our findings indicate that EBV status is not prognostic or predictive of treatment response in adults with PTLD. The high proportion of EBV-negative disease diagnosed in recent years highlights the need for new strategies for prevention and management of EBV-negative PTLD.


Asunto(s)
Infecciones por Virus de Epstein-Barr/complicaciones , Trastornos Linfoproliferativos/virología , Trasplante de Órganos , Complicaciones Posoperatorias/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Estudios Transversales , Infecciones por Virus de Epstein-Barr/diagnóstico , Femenino , Humanos , Lactante , Trastornos Linfoproliferativos/diagnóstico , Trastornos Linfoproliferativos/mortalidad , Trastornos Linfoproliferativos/terapia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/terapia , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Adulto Joven
2.
J Investig Allergol Clin Immunol ; 18(3): 156-62, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18564625

RESUMEN

OBJECTIVE: The aim of this study was to determine types and levels of airborne fungal spores in air-conditioned homes built after 1980 without obvious moisture problems during the 2004 summer (rainy season) in central Florida, USA. METHODS: Eighteen single-family homes were selected based on protocol questionnaire and cursory inspection, which revealed no obvious moisture or visible fungal growth. Non-cultured spores were collected with Air-O-Cell cassettes. Three indoor air samples and 2 outdoor air samples were collected from each home. One indoor and 2 outdoor samples were not interpretable. Fifty-three indoor and 34 outdoor air samples were analyzed by optical microscopy. RESULTS: Several spore types were detected in the indoor samples, at levels generally lower than those detected in the outdoor samples. Spores from the Penicillium/Aspergillus group were the most prevalent types indoors, exceeding the absolute levels and relative percentages of these spores outdoors. Ascospores and basidiospores were the most prevalent spore types outdoors. The percentages of other spore types (Cladosporium and Curvularia) were similar in the indoor and outdoor samples. Moisture-indicator fungi (Chaetomium, Stachybotrys, and Ulocladium species) were nearly absent in both indoor and outdoor samples. CONCLUSION: Airborne fungal spores are present in average central Florida homes without obvious moisture problems during the summer, at levels that are lower than those found outdoors. Spores from the Penicillium/Aspergillus group are prevalent in these homes, and moisture-indicator fungi (Chaetomium, Stachybotrys, and Ulocladium species) are nearly absent. Despite climatic differences, airborne fungal spore types and levels in central Florida houses are similar to those found in other geographical locations.


Asunto(s)
Microbiología del Aire , Contaminación del Aire Interior/análisis , Monitoreo del Ambiente , Esporas Fúngicas/aislamiento & purificación , Florida , Humanos , Humedad , Proyectos Piloto
3.
Int J Lab Hematol ; 37 Suppl 1: 61-71, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25976962

RESUMEN

The classical myeloproliferative neoplasms (MPNs) consist of chronic myelogenous leukemia (CML) and the non-CML MPNs, polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Molecular testing plays a crucial role in each of these disease entities. In this review, we discuss the role and caveats of BCR-ABL1 fusion transcript evaluation in CML diagnosis and monitoring, as well as ABL1 kinase mutation testing in the setting of tyrosine kinase inhibitor resistance. We also focus on JAK2, MPL, and CALR mutations in PV, ET, and PMF.


Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Policitemia Vera/diagnóstico , Mielofibrosis Primaria/diagnóstico , Trombocitemia Esencial/diagnóstico , Proteínas de Fusión bcr-abl/genética , Humanos , Janus Quinasa 2/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Mutación , Policitemia Vera/genética , Mielofibrosis Primaria/genética , Receptores de Trombopoyetina/genética , Trombocitemia Esencial/genética
4.
Am J Med ; 111(6): 480-8, 2001 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11690575

RESUMEN

The majority of clonal hematologic syndromes, including lymphoproliferative, myeloproliferative, and myelodysplastic disorders, tend to undergo transformation. However, the frequency of transformation varies widely. For example, transformation is almost invariable in chronic myelogenous leukemia, but it is infrequent in other myeloproliferative disorders. Similarly, transformation occurs in approximately 33% of follicular lymphomas but less commonly in other lower-grade lymphomas. At a genetic level, although some secondary lesions are seen across the spectrum of transformation syndromes (such as loss of function of p53 and p15/p16), there is considerable intra- and interdisease variability, with no common denominator. This review of the literature will discuss these transformations, noting their frequency, pathologic changes observed, clinical syndromes described, underlying genetic correlates, and prognostic and therapeutic implications.


Asunto(s)
Progresión de la Enfermedad , Enfermedades Hematológicas/genética , Enfermedades Hematológicas/fisiopatología , Enfermedades Hematológicas/patología , Humanos , Pronóstico , Síndrome
5.
J Mol Diagn ; 3(4): 133-40, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11687596

RESUMEN

To evaluate current diagnostic methods used for the evaluation of T cell receptor (TCR) gene rearrangements, 24 different laboratories analyzed 29 lymphoid neoplasm samples of extracted DNA and paraffin-embedded tissue and were asked to complete a technical questionnaire related to the testing. Participating laboratories performed Southern blot and polymerase chain reaction (PCR) testing for rearrangements of the TCRbeta chain gene and PCR for the TCRgamma chain gene rearrangements. Of 14 laboratories performing TCRbeta Southern blot analysis, there was complete agreement in 10 of 14 cases, with some false negative results obtained in 4 cases. No false positive results were obtained by Southern blot analysis. TCRbeta PCR analysis was only performed by two laboratories, and only 47.1% of positive samples were detected. Twenty-one laboratory results were obtained for TCRgamma PCR. This method showed an overall detection rate of 77.9% for T cell gene rearrangements with a 4.1% false positive rate, as compared to both TCRgamma Southern blot analysis results and immunophenotyping. The detection rate for TCRgamma PCR, however, significantly differed when extracted DNA samples from frozen tissue were compared to paraffin-embedded tissue (85.4% versus 65.9%; P = 0.0005). Significant differences in true positive results were obtained when laboratories using primers directed against multiple TCRgamma variable regions (V1-8 plus one to three other primer sets) were compared to laboratories that used only a single set of TCR primers directed against the V1-8 (P < 0.0001). Other technical factors significantly affecting results were also identified. These findings provide useful data on the current state of diagnostic TCR testing, highlight the risk of false negative results for TCR testing directed against only portions of the TCRgamma gene, and identify limitations of testing of paraffin-embedded tissues in some laboratories.


Asunto(s)
Reordenamiento Génico de la Cadena gamma de los Receptores de Antígenos de los Linfocitos T/genética , Genes Codificadores de la Cadena gamma de los Receptores de Linfocito T/genética , Leucemia/diagnóstico , Linfoma/diagnóstico , Receptores de Antígenos de Linfocitos T/genética , Análisis de Secuencia de ADN/métodos , Southern Blotting , Células Clonales , Reacciones Falso Negativas , Reacciones Falso Positivas , Secciones por Congelación , Humanos , Inmunofenotipificación , Laboratorios , Leucemia/genética , Linfoma/genética , Variaciones Dependientes del Observador , Adhesión en Parafina , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados
6.
Am J Surg Pathol ; 25(7): 949-55, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11420468

RESUMEN

SHP-1 is a protein phosphotyrosine phosphatase that plays an important role in modulating intracellular signaling, which regulates cell activation, proliferation, differentiation, and migration. It is a negative regulator of signal transduction induced by a number of cell receptors. Our immunohistochemical examination of paraffin-embedded reactive lymph nodes and lymphoid tissues revealed that B lymphocytes in follicle germinal centers do not express SHP-1. A weak staining of the B cells in the germinal center light zones was detected when an ultrasensitive amplification system was used. In contrast, normal B cells in mantle and marginal zones as well as interfollicular B lymphocytes and plasma cells displayed strong immunoreactivity. This pattern of SHP-1 expression was repeated in small B-cell lymphomas. All cases of mantle cell lymphoma (12 of 12), marginal zone lymphoma (10 of 10), and chronic lymphocytic leukemia/small lymphocytic lymphoma (13 of 13) expressed SHP-1 protein. However, only 1 of 30 cases of grade 1 follicle center cell lymphoma expressed SHP-1. Our observations highlight the biologic functions of SHP-1 and demonstrate that the SHP-1 expression pattern by small B-cell lymphomas reflects the maturation stage of their normal cell counterparts. These results indicate that determination of SHP-1 expression may help in the differential diagnosis of small B-cell lymphomas.


Asunto(s)
Linfocitos B/fisiología , Leucemia Linfocítica Crónica de Células B/metabolismo , Linfoma de Células B/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Senescencia Celular , Humanos , Inmunohistoquímica/métodos , Péptidos y Proteínas de Señalización Intracelular , Leucemia Linfocítica Crónica de Células B/patología , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Tejido Linfoide/metabolismo , Tejido Linfoide/patología , Linfoma de Células B/patología , Proteína Tirosina Fosfatasa no Receptora Tipo 6 , Valores de Referencia , Coloración y Etiquetado/métodos
7.
Bone Marrow Transplant ; 13(2): 115-23, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8205079

RESUMEN

Our previous studies have shown that IL-2 activated bone marrow cells develop potent tumoricidal activity in vitro and in vivo. With the dual aim of in vitro purging and generation of effectors which could mediate graft-versus-leukemia effects in vivo, IL-2 activation of human bone marrow in long-term cultures (LTC) was tested. Marked cytotoxicity was seen against A375 (melanoma), K562 (CML) and Daudi (lymphoma) cell lines in IL-2 (1000 U/ml) stimulated cultures. Hematopoietic progenitor cell number in these cultures was assessed by day 14 clonogenic assays. In 1-week-old IL-2 stimulated cultures a higher number of clonogenic cells was seen than control LTCs without IL-2. However, thereafter accelerated decrease in the number of clonogenic cells was seen in IL-2 cultures. In vitro purging efficacy was tested by elimination of A375 and K562 cells mixed with normal marrow at 1:10 and 1:100 ratios and co-cultured for 10 days. In IL-2 stimulated cultures, A375 cells capable of proliferation were not detectable at both mixing ratios. K562 elimination was complete only at 1:100 ratio. After 10 days in culture, no Ph1-positive metaphases were seen in IL-2 stimulated BM cultures of 4 patients with CML. These results indicate that IL-2 activation of BM in 1-2 week cultures can lead to generation of marked anti-tumor cytotoxicity and effective in vitro purging in a variety of tumor types.


Asunto(s)
Purgación de la Médula Ósea , Trasplante de Médula Ósea , Médula Ósea/patología , Interleucina-2/fisiología , Médula Ósea/fisiología , Células de la Médula Ósea , División Celular , Células Cultivadas , Células Madre Hematopoyéticas/patología , Células Madre Hematopoyéticas/fisiología , Humanos , Interleucina-2/farmacología , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Linfoma/patología , Linfoma/terapia , Melanoma/patología , Melanoma/terapia , Fenotipo , Factores de Tiempo , Células Tumorales Cultivadas
8.
Am J Clin Pathol ; 112(1 Suppl 1): S76-92, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10396303

RESUMEN

Molecular dissection of physiologic and pathologic genetic phenomena in hematologic malignancy has provided the pathologist with a broad menu of new assays. By integrating the data gleaned from these techniques we can formulate more rational and biologically based diagnoses, which should lead to the ultimate goal of targeted therapy for these specific entities. We summarize some of the more relevant molecular genetic assays and present an overview of those genetic mechanisms usually evaluated in the current practice of hematopathology. The usefulness of such assays extends beyond refining diagnoses in that they also provide relevant prognostic information. Moreover, since most are based on the polymerase chain reaction and reverse transcriptase polymerase chain reaction, we are more sensitively able to monitor for residual disease after attempts at curative therapy, and our definition of remission has been dramatically altered. However, molecular genetic tests are not without limitations, and we must remain cognizant of their cost effectiveness and be aware of current deficiencies in standardization. The challenge will be to meaningfully and economically harness and integrate the information we obtain from these and future technologies into appropriate clinical practice.


Asunto(s)
ADN de Neoplasias/análisis , Técnicas Genéticas , Leucemia/patología , Linfoma/patología , ARN Neoplásico/análisis , Humanos , Leucemia/genética , Linfoma/genética
9.
Am J Clin Pathol ; 91(6): 633-8, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2524964

RESUMEN

Immunophenotypic studies have a well-documented role in the assignment of lineage in the lymphoproliferative disorders. With the exception of mature B-cell disorders, it is difficult to demonstrate clonality by immunophenotypic studies. The advent of specific DNA probes for immunoglobulin and T-cell receptor genes has greatly facilitated the detection of clonality and, to a lesser degree, lineage, in these cases. The authors have evaluated the diagnostic utility of these probes and compared them with standard immunophenotyping in 65 patients with a variety of lymphoproliferative disorders. Their results show a significant correlation (P less than 0.01) between lineage assignment as determined by phenotyping and gene rearrangement studies, with the latter far superior in determining clonality. Furthermore, analysis of gene rearrangements facilitated the documentation of lineage and/or clonality in six cases in which standard techniques had failed. Although the scientific basis of the study of gene rearrangements has been well established, the authors wish to emphasize the role that these techniques have in evaluating problem cases in the routine diagnostic laboratory.


Asunto(s)
Reordenamiento Génico , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas lambda de Inmunoglobulina/genética , Trastornos Linfoproliferativos/diagnóstico , Receptores de Antígenos de Linfocitos T/genética , Sondas de ADN , Técnica del Anticuerpo Fluorescente , Humanos , Receptores de Antígenos de Linfocitos T alfa-beta
10.
Am J Clin Pathol ; 111(6): 759-66, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10361511

RESUMEN

Flow cytometric immunophenotypic analysis is critical in diagnosis and classification of acute leukemia and has been used after therapy to monitor for minimal residual disease. However, the presence of normal B-cell precursors, hematogones, particularly in the context of treated pediatric B-cell precursor acute lymphoblastic leukemia (BP-ALL), may confound such evaluation. In this study, the value of more specific genotypic markers (polymerase chain reaction evaluation of 2 antigen receptor genes) was assessed to resolve this issue. Flow cytometric analysis of enriched mononuclear cells revealed 1% to 20% precursor B cells (PBCs), based on expression of 1 or more pan-B cell antigens in addition to CD10, CD34, and terminal deoxynucleotidyl transferase in all 14 patients studied. Inasmuch as this mimicked the immunophenotype of the original leukemic clone, PBCs, in isolation, were considered suspicious for minimal residual disease. However, 11 of the 14 posttherapy specimens (79%) revealed no monoclonally rearranged antigen receptor genes, and 7 of these 11 patients had trackable genotypic markers at presentation. Accordingly, by PCR these 7 patients had complete molecular remission, supported by clinical follow up of 16 to 73 months. Among the remaining 4 patients with PCR-negative disease, 3 continue in remission, confirming the interpretation of false-positive flow cytometric analysis. In conclusion, flow cytometric monitoring of posttherapy bone marrow specimens from patients with BP-ALL may be misleading, if considered in isolation, in falsely suggesting the presence of minimal residual disease. Rather, PCR for antigen receptor gene rearrangements is a valuable and specific tool, helpful in differentiating hematogones from minimal residual disease in patients with treated BP-ALL whose bone marrow harbors increased PBCs.


Asunto(s)
Subgrupos de Linfocitos B/citología , Médula Ósea/patología , Reordenamiento Génico , Genes de Inmunoglobulinas , Genes Codificadores de los Receptores de Linfocitos T , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Adolescente , Adulto , Médula Ósea/inmunología , Linfoma de Burkitt/genética , Linfoma de Burkitt/inmunología , Linfoma de Burkitt/patología , Linfoma de Burkitt/terapia , Niño , Preescolar , Citometría de Flujo , Humanos , Inmunofenotipificación , Reacción en Cadena de la Polimerasa , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Inducción de Remisión
11.
Diagn Mol Pathol ; 4(1): 8-13, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7735561

RESUMEN

To determine efficiently the clonality of B-cell lymphoproliferative disorders, we modified an immunoglobulin heavy-chain (IGH) gene rearrangement polymerase chain reaction (PCR) assay that requires only a single primer germline variable (VH) and joining (JH) pair and does not involve nested priming, blot hybridization, radioactivity, or sequencing of the amplified PCR product. This simple PCR technique enabled detection of IGH gene rearrangements in as little as 10 pg (one cell equivalent) of DNA or when the clonal-to-polyclonal B-cell ratio was experimentally set at 1:1000. We detected IGH gene rearrangements in 83.5% (71 of 85) of clonal B-cell processes, a sensitivity approaching that of more cumbersome multiple primer and nested primer assays. Moreover, this technique is equally effective with fixed tissues, either B5 or formalin, and can be performed on minute samples, histologic sections, fine-needle aspirates, or cerebrospinal fluids. When compared with conventional Southern blot analysis using a genomic JH probe, the PCR assay demonstrated IGH gene rearrangements in 82% (37 of 45) of B-cell processes positive by Southern blot. No false-positive results were observed in 29 negative control tissues. We now use IGH gene PCR routinely in our laboratory for the detection of clonal B-cells in virtually any tissue sample as an aid in early diagnosis, staging, and monitoring, and the Southern blot procedure is reserved for only a minority of diagnostic cases. for only a minority of diagnostic cases.


Asunto(s)
Southern Blotting/métodos , Reordenamiento Génico de Cadena Pesada de Linfocito B/genética , Reacción en Cadena de la Polimerasa/métodos , Linfocitos B/inmunología , Secuencia de Bases , ADN de Neoplasias/genética , Humanos , Trastornos Linfoproliferativos/genética , Trastornos Linfoproliferativos/inmunología , Datos de Secuencia Molecular , Sensibilidad y Especificidad
12.
Cancer Genet Cytogenet ; 62(2): 134-9, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1394098

RESUMEN

We report a patient with Ph+ chronic myelogenous leukemia (CML) whose recurrent blast crises were associated with marrow eosinophilia and inv(16). After intensive chemotherapy, for each blast crisis, the patient reentered chronic phase with disappearance of both the inv(16) and the eosinophilia.


Asunto(s)
Crisis Blástica , Aberraciones Cromosómicas , Cromosomas Humanos Par 16 , Eosinofilia/complicaciones , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Adulto , Humanos , Cariotipificación , Leucemia Mielógena Crónica BCR-ABL Positiva/complicaciones , Masculino
13.
Heart Lung ; 14(6): 594-8, 1985 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3850879

RESUMEN

Thousands of health care providers spend time, money, and energy each year taking the AHA-sponsored ACLS courses, and ACLS-certified health care providers are frequently given greater job responsibility than other health care providers in the same setting. The purpose of this study was to determine the effect of an ACLS course on the ability of health care providers to perform ACLS in a simulated situation. A nonequivalent control group design was used. The sample consisted of 76 health care providers whose job responsibilities included ACLS. The Mega-Code skill station from the ACLS course was used to evaluate ACLS performance. Chi-square analyses showed a significant (p less than 0.05) difference in the posttest pass/fail results of the two groups and a significant (p less than 0.05) difference in the changes from pretest to posttest of the two groups. The research hypotheses were supported, and the researches concluded that the course had a positive effect on the subjects' ACLS ability.


Asunto(s)
Empleos en Salud/educación , Paro Cardíaco/terapia , Cuidados para Prolongación de la Vida , Resucitación , Competencia Clínica , Educación Continua , Femenino , Humanos , Masculino , Enseñanza/métodos
14.
Ecancermedicalscience ; 8: 496, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25624877

RESUMEN

The 2014 OECI Oncology Days was held at the 'Prof. Dr. Ion Chiricuta' Oncology Institute in Cluj, Romania, from 12 to 13 June. The focus of this year's gathering was on developments in personalised medicine and other treatment advances which have made the cost of cancer care too high for many regions throughout Europe.

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