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Anisotropic alignment of collagen fibres in musculoskeletal tissues is responsible for the resistance to mechanical loading, whilst in cornea is responsible for transparency. Herein, we evaluated the response of tenocytes, osteoblasts and corneal fibroblasts to the topographies created through electro-spinning and solvent casting. We also evaluated the influence of topography on mechanical properties. At day 14, human osteoblasts seeded on aligned orientated electro-spun mats exhibited the lowest metabolic activity (P < 0.001). At day 5 and at day 7, no significant difference was observed in metabolic activity of human corneal fibroblasts and bovine tenocytes respectively seeded on different scaffold conformations (P > 0.05). Osteoblasts and corneal fibroblasts aligned parallel to the direction of the aligned orientated electro-spun mats, whilst tenocytes aligned perpendicular to the aligned orientated electro-spun mats. Mechanical evaluation demonstrated that aligned orientated electro-spun fibres exhibited significant higher stress at break values than their random aligned counterparts (P < 0.006) and random orientated electro-spun fibres exhibited significant higher strain at break values than the aligned orientated scaffolds (P < 0.006). While maintaining fibre structure, we also developed a co-deposition method of spraying and electro-spinning, which enables the incorporation of microspheres within the three-dimensional structure of the scaffold.
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Tensión Superficial , Andamios del Tejido , Animales , Bovinos , Células Cultivadas , Colágeno , Colorantes Fluorescentes , Humanos , Microscopía Electrónica de Rastreo , Osteoblastos/citologíaRESUMEN
INTRODUCTION: Flow cytometric immunophenotyping (FCI) is an integral part in the diagnosis and classification of hematologic malignancies. FCI results also influence therapeutic decisions and disease prognosis. ClearLLab LS is a 12-antibody 10-color cocktail provided in dry format designed as a screen for patients suspected of having hematolymphoid disease. METHODS: A blinded comparison between ClearLLab LS, (CD8-FITC, Kappa-FITC,CD4-PE, Lambda-PE, CD19-ECD, CD56-PE-Cy5.5, CD10-PE-Cy7, CD34-APC, CD5-APC-A700, CD20-APC-A750, CD3-PB, and CD45-KrO), ClearLLab Reagents (five-color, 17-antibodies) and individual Laboratory Developed Tests (LDTs), was conducted at four laboratories. Evaluation of ClearLLab LS was performed on 210 specimens, compared to the five-color ClearLLab Reagents (IVD and CE-IVD), and a subset (n = 167) to LDTs. RESULTS: ClearLLab LS showed good agreement to ClearLLab Reagents in detecting the absence (104/104) or presence (106/106) of abnormal populations. Of specimens with abnormal populations the ClearLLab LS agreed with the ClearLLab Reagent for neoplasm maturity assessment (70/70 mature and 36/36 immature). Out of 167 specimens with LDTs results, 86 contained abnormal population(s), ClearLLab LS detected 82 (95.3%) of cases. Of the 4 cases not detected by ClearLLab LS, 3 were plasma cell neoplasms and 1 was a mature T cell malignancy. Eighty-one samples with no hematological malignancy as analyzed by LDT were also negative by ClearLLab LS (100% agreement). ClearLLab LS agreed with LDTs assessment of neoplasms' maturity (55/55 mature and 27/27 immature). CONCLUSION: ClearLLab LS screening tube showed excellent agreement between ClearLLab Reagents and with LDT's. The presence of CD34 and CD10 in the tube allowed the detection of blast populations in several acute leukemias and myeloid neoplasms that were tested. © 2017 International Clinical Cytometry Society.
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Linfocitos B/citología , Citometría de Flujo , Inmunofenotipificación , Linfoma/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Linfocitos T/citología , Linfocitos B/inmunología , Femenino , Humanos , Linfoma/inmunología , Masculino , Fenotipo , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Linfocitos T/inmunologíaRESUMEN
Flow cytometry is an invaluable technology in the examination of blood, bone marrow, tissue and body fluids for the presence or absence of hematological disease. It is used in both diagnostic and follow-up testing, with an increasingly important role in the detection of very small residual disease populations (Minimal Residual Disease, MRD) However, flow cytometry immunophenotyping of leukemia and lymphoma is highly dependent on interpretation of results and with the increased complexity of 8-10 color instruments routinely used in clinical laboratories, knowledge of disease-defining populations is increasingly important as is recognizing normal and reactive patterns. This manuscript presents case studies with flow cytometric patterns encountered in routine screening of samples sent for leukemia and lymphoma immunophenotyping, focusing mainly on B-cell disorders which may be missed or incorrectly interpreted by the laboratory (including a hematopathologist) performing the test. Case studies are used to illustrate our laboratory's standardized approach to the interpretation of flow cytometric data. In addition to a standardized approach, these cases emphasize the importance of interpretative skills of technologist and hematopathologists in recognizing abnormal patterns in detecting hematological malignancies.
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Citometría de Flujo/métodos , Inmunofenotipificación/métodos , Leucemia de Células B , Linfoma de Células B , Anciano , Niño , Preescolar , Femenino , Humanos , Leucemia de Células B/sangre , Leucemia de Células B/diagnóstico , Linfoma de Células B/sangre , Linfoma de Células B/diagnóstico , Masculino , Persona de Mediana EdadRESUMEN
PurposeAdenoid cystic carcinoma (ACC) represents ~10-15% of salivary neoplasms and almost universally exhibits a lethal clinical course. ACC is also known to occur in the lacrimal gland. ACC is characterized by its heterogeneous morphology and may demonstrate tubular, cribriform, and/or solid architectural patterns. Unfortunately, these histopathological features are not specific to ACC and can be seen in other salivary gland-type neoplasms, introducing a diagnostic dilemma. The discovery of fusion transcripts has revolutionized the diagnosis, surveillance, and treatment of epithelial malignancies. In several anatomic subsites ACC is frequently characterized by a fusion transcript involving genes MYB and NFIB; more specifically, t(6;9)(q22-23;p23-24). This study explores the incidence of MYB rearrangement in cases of lacrimal gland ACC using fluorescent in situ hybridization.Materials and methodsRetrospective clinical and histopathological review of 12 cases of lacrimal gland ACC seen at Mayo Clinic over a 25-year period (1990-2015) was performed. Demographic and clinical data were obtained from medical records. Surgical pathology archival material including H&E slides and immunostains was re-examined. Formalin-fixed paraffin-embedded material was further evaluated using immunohistochemistry when appropriate. Fluorescent in situ hybridization (FISH) using a MYB break-apart probe was applied to all histologically confirmed cases of ACC and benign salivary gland parenchyma.ResultsThe median patient age was 53.6 years (range 12-64) and distributed equally by gender (six male and six female). Rearrangement of MYB was identified using FISH in seven cases (58%). Twenty-five sections of benign salivary gland parenchyma showed no evidence of MYB rearrangement. Primary surgical resection was most common treatment, and 78% of the patient received adjuvant radiation therapy. Median overall survival (OS) was 11 years. Rearrangement of MYB did not affect OS.ConclusionsIn summary, our results indicate that the MYB rearrangement defines a significant subset of lacrimal gland ACCs. Importantly, FISH for MYB rearrangement may be used as a diagnostic tool during pathological examination of lacrimal gland neoplasms. Our results showed no relationship between rearrangement status and clinical outcome. Lastly, the presence of t(6;9) in ACC may provide a platform for molecular-targeting strategies in the future.
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Carcinoma Adenoide Quístico/genética , Neoplasias del Ojo/genética , Enfermedades del Aparato Lagrimal/genética , Aparato Lagrimal/patología , Proteínas Oncogénicas v-myb/genética , Adolescente , Adulto , Biomarcadores de Tumor/genética , Biopsia , Carcinoma Adenoide Quístico/diagnóstico , Carcinoma Adenoide Quístico/metabolismo , Niño , Neoplasias del Ojo/diagnóstico , Neoplasias del Ojo/metabolismo , Femenino , Reordenamiento Génico , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Enfermedades del Aparato Lagrimal/diagnóstico , Enfermedades del Aparato Lagrimal/metabolismo , Masculino , Persona de Mediana Edad , Proteínas Oncogénicas v-myb/metabolismo , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: Two lines of evidence indirectly implicate the tumor suppressor p53 (also known as TP53) gene in glioma development. First, germline mutations of the p53 gene are associated with increased susceptibility to glioma. Second, chromosome 17p deletions and p53 gene mutations are found frequently in sporadic gliomas of all malignancy stages. These observations suggest that mutations of the p53 gene may be early events in glioma development. PURPOSE: Our purpose was to analyze 15 low-grade astrocytic gliomas that progressed to higher-grade gliomas, examining the status of the p53 gene in both the initial and recurrent tumors. Also, we explored the relationships between p53 status, DNA ploidy, tumor grade, and patient survival. METHODS: Fifteen low-grade gliomas that recurred as tumors of higher grade 17-102 months after initial treatment (biopsy, resection, radiotherapy, or chemotherapy) were identified from hospital records of patients (eight male and seven female) aged 31-68 years. Pathologic diagnosis was re-evaluated. Polymerase chain reaction (PCR)-single-strand conformation polymorphism and DNA sequencing were performed on tissue samples from the initial and recurrent tumors of each patient, using oligonucleotide PCR primers directed to exons 5-9 of the p53 gene. p53 expression was determined by immunohistochemistry and DNA ploidy evaluated by DNA flow cytometry. RESULTS: Eight (53%) of fifteen tumors had p53 mutations in exons 5-9. Nine (64%) of fourteen were immunopositive initially, and eight of these were also immunopositive at recurrence. p53 gene status was significantly associated with p53 expression in the initial tumor (P = .02), and p53 expression at initial diagnosis was significantly related to tumor pathology at recurrence (P = .03). Patients with p53 mutant tumors survived nearly twice as long as those without mutations (median survival, 61 versus 33 months; P = .031). There was no significant difference in recurrence-free survival between patients with p53 mutant and nonmutant tumors (48 versus 33 months; P = .37), but there was a significant difference in postrecurrence survival (17 versus 2 months; P = .019). CONCLUSION: Low-grade tumors that recurred as anaplastic gliomas were characterized by p53 gene mutation, immunopositivity, and DNA non-diploidy. Low-grade tumors that recurred as glioblastomas generally had intact p53 genes and were immunonegative. These findings suggest that histologically indistinguishable, low-grade astrocytic gliomas that are destined to progress to higher grades, do so along two distinct clinicopathologic pathways (either stepwise to anaplastic glioma, then glioblastoma, or directly to glioblastoma) marked by the presence or absence of p53 mutation.
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Astrocitoma/genética , Genes p53 , Mutación , Proteína p53 Supresora de Tumor/análisis , Adulto , Anciano , Astrocitoma/química , Astrocitoma/patología , Secuencia de Bases , ADN de Neoplasias/genética , Femenino , Citometría de Flujo , Humanos , Inmunoquímica , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Ploidias , Reacción en Cadena de la Polimerasa , Análisis de Supervivencia , Proteína p53 Supresora de Tumor/genéticaRESUMEN
Papers presented at this Workshop report clues which suggest further research on the role of dietary fat in the etiology of some forms of cancer. The research has not yet yielded information which can be used to make responsible dietary recommendations to the public. The suggestion that dietary animal fats are associated with "fat-related" cancers is not well documented. Virtually all of the increase in fat consumption in the United States during the 20th century has been due to vegetable fats. Many of these vegetable oils are partially hydrogenated, resulting in the accumulation of significant amounts of trans-fatty acids in such products as margarines and shortenings. It is suggested that more research attention should be given to the effects of dietary trans-fatty acids on animal physiology.
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Dieta/efectos adversos , Grasas de la Dieta/efectos adversos , Ácidos Grasos Insaturados , Humanos , Hidrogenación , Isomerismo , Margarina , Neoplasias/etiología , Estados UnidosRESUMEN
We examined the effect of p53 inactivation on the response of U87MG glioma cells to 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). These studies were motivated by three observations: (a) some human astrocytomas are sensitive to BCNU and some are resistant; (b) chemosensitive astrocytomas are more likely to be found in young adults whose tumors are more likely to harbor a p53 mutation; and (c) mouse astrocytes lacking the p53 gene are more sensitive to BCNU than wild-type cells. Here, we observed that p53 inactivation by transfection with pCMV-E6 sensitized U87MG cells to BCNU. Compared with control U87MG-neo cells with intact p53 function, the clonogenic survival of U87MG-E6 cells exposed to BCNU was reduced significantly. In U87MG-E6 cells, sensitization to BCNU was associated with failure of p21(WAF1) induction, transient cell cycle arrest in S phase, accumulation of polyploid cells, and significant cell death. In contrast, resistance to BCNU in U87MG-neo cells was associated with up-regulation of p53, prolonged induction of p21(WAF1), sustained cell cycle arrest in S phase, and enhancement of DNA repair. U87MG cells with disrupted p53 function were less able to repair BCNU-induced DNA damage and survive this chemotherapeutic insult. The question arises of whether p53 dysfunction might be a chemosensitizing genetic alteration in human astrocytic gliomas.
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Antineoplásicos Alquilantes/farmacología , Carmustina/farmacología , Glioma/tratamiento farmacológico , Glioma/genética , Proteína p53 Supresora de Tumor/fisiología , Ciclo Celular/efectos de los fármacos , Supervivencia Celular/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/biosíntesis , Ciclinas/genética , Reparación del ADN/fisiología , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Glioma/patología , Humanos , Transfección , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/biosíntesis , Proteína p53 Supresora de Tumor/genéticaRESUMEN
Since its introduction in the early 1990s, layer-by-layer (LbL) self-assembly of films has been widely used in the fields of nanoelectronics, optics, sensors, surface coatings, and controlled drug delivery. The growth of this industry is propelled by the ease of film manufacture, low cost, mild assembly conditions, precise control of coating thickness, and versatility of coating materials. Despite the wealth of research on LbL for biomolecule delivery, clinical translation has been limited and slow. This review provides an overview of methods and mechanisms of loading biomolecules within LbL films and achieving controlled release. In particular, this review highlights recent advances in the development of LbL coatings for the delivery of different types of biomolecules including proteins, polypeptides, DNA, particles and viruses. To address the need for co-delivery of multiple types of biomolecules at different timing, we also review recent advances in incorporating compartmentalization into LbL assembly. Existing obstacles to clinical translation of LbL technologies and enabling technologies for future directions are also discussed.
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Flow cytometric enumeration of CD34(+) hematopoietic stem and progenitor cells (HPC) is widely used to evaluate the adequacy of peripheral blood stem cell grafts and is also useful for planning the apheresis sessions needed to obtain these grafts. A state-of-the-art method to enumerate CD34(+) cells has been developed that makes use of a multiparameter definition of HPC, based on their light scatter characteristics and dim expression of CD45, utilizing fluorescent counting beads. This approach allows the absolute CD34(+) cell count to be determined directly from a flow cytometer. The method can be extended with a viability stain and additional markers for further immunologic characterization of CD34(+) cells, and has been successfully implemented in multicenter trials. Using such a standardized assay, it should be possible to define more accurately the lower threshold for a safe HPC graft in terms of short- and long-term hematopoietic reconstitution. Semin Hematol 38:139-147.
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Citometría de Flujo/métodos , Células Madre Hematopoyéticas/citología , Inmunofenotipificación/métodos , Células Madre/citología , Animales , Recuento de Células , Células Madre Hematopoyéticas/clasificación , Células Madre Hematopoyéticas/inmunología , Humanos , Células Madre/clasificación , Células Madre/inmunologíaRESUMEN
Twenty-four adult men and women, classified as carbohydrate-sensitive on the basis of an exaggerated insulin response to a sucrose load, consumed diets containing 5, 18, and 33% of calories as sucrose for 6 wk each in a cross-over design. The diets contained identical natural and processed foods except for a patty containing 2, 15, or 30% of the calories as sucrose at the expense of wheat starch. Carbohydrate, fat, and protein provided 44, 42, and 14% of the calories, respectively. Of total calories, 25% were consumed at breakfast and 75% at dinner. Initial body weights of the subjects were essentially maintained. Fasting serum insulin levels increased with the sucrose content of the diet and were significantly higher in men than in women. Mean fasting glucose was significantly higher on either 18 or 33% sucrose than on 5% sucrose. The sucrose content of the diet did not affect fasting serum glucagon. When compared to the insulin response to a sucrose load (2 g/kg body weight) after consuming the 5% sucrose diet, serum insulin was significantly higher at 1 h after the 18% sucrose diet and at 0.5, 1, 2, and 3 h after the 33% sucrose diet. Except after 2 h, the glucose response was significantly greater after the 18 and 33% sucrose diets than after the 5% sucrose diet. These results indicate that sucrose intake by carbohydrate-sensitive individuals, even at levels approximating the average United States intake, can produce undesirable changes in several parameters associated with glucose tolerance.
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Glucemia/metabolismo , Hiperinsulinismo/sangre , Insulina/sangre , Sacarosa , Dieta , Ingestión de Energía , Ayuno , Femenino , Humanos , Cinética , Masculino , Sacarosa/administración & dosificaciónRESUMEN
The INR system was developed to standardize PT reporting in patients on oral anticoagulants. We prospectively collected blood samples from 29 patients with liver impairment (INR 1.5-3.5). Control patients were on warfarin (n = 31). PT's were measured on an ACL-300 with three thromboplastin reagents. INR's were calculated using instrument specific ISI's. Other tests performed were FDP's, fibrinogen, aPTT, factors II, V, VII and X. The INR's for each patient in the study population using the three thromboplastin reagents were significantly different (p = 0.0001). Those for the control population were not (p = 0.0658). Fibrinogen, factors V, II and X were different at the 5% level of significance between the populations. FDP's were detected in 17 study subjects. The INR system is not valid for comparison of patients with liver impairment because different reagents do not give the same INR for the same sample. It is, however, no less valid than the use of PT with different thromboplastin reagents. Further study is recommended.
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Hepatopatías/sangre , Tiempo de Protrombina , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Indicadores y Reactivos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estándares de Referencia , Reproducibilidad de los Resultados , Tromboplastina , Warfarina/uso terapéutico , Organización Mundial de la SaludRESUMEN
Reduced CD34(+) cell viability due to cryopreservation has unknown effects on subsequent hematopoietic engraftment in autologous transplantation. Thirty-six consecutive autologous peripheral stem cell collections were analyzed for absolute viable CD34(+) cell numbers at the time of stem cell collection and prior to re-infusion. Viable CD34(+) cells were enumerated using single platform flow cytometry and the molecular exclusion dye 7-amino actinomycin D. The median number of viable CD34(+) cells was 3.6 x 10(6)/kg at the time of harvest and 2.0 x 10(6)/kg after thawing. When viable CD34(+)cells enumerated after thawing were <2.0, 2.0-5.0, or >5.0 x 10(6)/kg, the median time to platelet engraftment was 17, 12 and 10 days, respectively (P < 0.05 for comparison of the group with <2.0 x 10(6)/kg and the other two groups), and the median time to neutrophil engraftment was 13, 14 and 12 days, respectively (P = NS). A minimum of 2.0 x 10(6) CD34(+) cells/kg was harvested in 33 of 36 patients (92%) but only 19 of 36 (52%) patients met this threshold at the time of reinfusion. The reduced numbers of viable CD34(+) cells measured prior to re-infusion is associated with time to platelet engraftment and may be useful in monitoring stem cell loss during processing and identifying patients at risk of graft failure.
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Antígenos CD34/análisis , Supervivencia de Injerto , Trasplante de Células Madre Hematopoyéticas/normas , Adolescente , Adulto , Anciano , Recuento de Células , Supervivencia Celular , Criopreservación/normas , Trasplante de Células Madre Hematopoyéticas/métodos , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/inmunología , Humanos , Cinética , Persona de Mediana Edad , Neoplasias/terapia , Trasplante de Células Madre de Sangre Periférica/métodos , Trasplante de Células Madre de Sangre Periférica/normas , Pronóstico , Estudios Prospectivos , Manejo de Especímenes , Trasplante Autólogo/métodos , Trasplante Autólogo/normasRESUMEN
Patients (n = 69) with multiple myeloma undergoing peripheral blood stem cell collection (PBSC) were treated with cyclophosphamide and a combination of recombinant methionyl human granulocyte colony-stimulating factor (r-metHuG-CSF, filgrastim) and recombinant methionyl human stem cell factor (r-metHuSCF, ancestim). The objectives of this study were to determine: (1) The proportion of patients reaching a target yield of >or=5 x 10(6) CD34(+) cells/kg in one or two successive large-volume (20 liter) leukapheresis procedures; (2) the optimal collection time for leukapheresis; (3) mobilization kinetics of CD34(+) subsets in response to G-CSF/SCF. All patients were mobilized with cyclophosphamide (2.5 g/m(2)) on day 0 followed by filgrastim (10 microg/kg ) plus ancestim (20 microg/kg) commencing day 1 and continuing to day 11 or 12. Of the 65 evaluable patients, 57 were considered not heavily pretreated and 96.5% obtained a target of >or=5 x 10(6)/kg in one collection. The median CD34(+) cells/kg was 39.5 x 10(6) (range: 5.2-221.2 x 10(6)). Subset analysis demonstrated the number of CD38(-), CD33(-), and CD133(+) peaked at day 11; and CD34(+), CD90(+) cells peaked at day 10. The optimum day for leukapheresis was determined to be day 11. The median absolute peripheral blood CD34(+) cell numbers on day 11 was 665 x 10(6)/l (range: 76-1481 x 10(6)/l). Eight of the 10 heavily pretreated patients were evaluable: three achieved the target dose in one leukapheresis (37.5%) and three (37.5%) achieved the target dose with two leukaphereses. Use of this mobilization strategy allowed the collection of high numbers of CD34(+) cells and early progenitors and the ability to predictably schedule leukapheresis.
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Recuento de Células Sanguíneas , Movilización de Célula Madre Hematopoyética , Células Madre Hematopoyéticas , Leucaféresis/métodos , Mieloma Múltiple/sangre , Adulto , Anciano , Antígenos CD34/análisis , Ciclofosfamida , Femenino , Filgrastim , Citometría de Flujo , Factor Estimulante de Colonias de Granulocitos , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Inmunofenotipificación , Masculino , Persona de Mediana Edad , Mieloma Múltiple/terapia , Proteínas Recombinantes , Factor de Células Madre/análogos & derivadosRESUMEN
Enoxaparin after joint arthroplasty is effective prophylaxis against venous thromboembolism. This is usually given as a fixed dose without monitoring of anti-Xa levels. This study assesses the relationship between trough anti-Xa levels, body weight, and venous thromboembolism. Consenting patients at three institutions were treated with Enoxaparin 30 mg subcutaneously bis in die postoperatively until discharge. Chromogenic anti-Xa levels were measured on the fifth postoperative day by the method of Stachrome (Diagnostica Stago). All patients had bilateral compression doppler ultrasonography on day 10 or discharge and were followed for 12 weeks for evidence of venous thromboembolism. Eleven patients developed objectively confirmed venous thromboembolism during the study. In this study, there was poor correlation between weight and anti-Xa levels. In addition, body weight and anti-Xa levels of patients who developed venous thromboembolism were compared to those who did not and there were no significant differences between the two groups. In conclusion, this study shows that there is poor correlation of trough anti-Xa levels with body weight. Recognizing the low overall event rate this study does not support the need to monitor anti-Xa levels or adjusting the dose according to weight.
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Anticoagulantes/administración & dosificación , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Enoxaparina/administración & dosificación , Inhibidores del Factor Xa , Complicaciones Posoperatorias/prevención & control , Trombosis/prevención & control , Anciano , Peso Corporal , Femenino , Humanos , Masculino , Complicaciones Posoperatorias/fisiopatologíaRESUMEN
Two divided visual field priming experiments were designed to determine the nature of lexical retrieval in the cerebral hemispheres by studying the facilitation of semantic features of unambiguous nouns. Unambiguous nouns have a single meaning, yet semantic features associated with these nouns may vary in the degree to which they are compatible with this single meaning (e.g., LAMB-WOOL as compared with LAMB-CHOPS). Results suggest that the left hemisphere selects both strongly and weakly associated semantic features that are compatible with the dominant representation of the noun. Dominance compatibility, rather than association strength, seems to be the more important factor for deciding what features are maintained in the left hemisphere. In contrast, the right hemisphere maintains more varied information, including features that are less compatible with the dominant representation (Experiment 1) and context information (Experiment 2).
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Encéfalo/fisiología , Lateralidad Funcional/fisiología , Semántica , Vocabulario , Toma de Decisiones , Humanos , Recuerdo Mental/fisiología , Estimulación Luminosa , Tiempo de Reacción/fisiología , Factores de Tiempo , Campos Visuales/fisiologíaRESUMEN
P-glycoprotein (PgP), a transmembrane protein, has been associated with multiple drug resistance. We examined 42 patients with chronic lymphocytic leukemia immunohistochemically using the monoclonal antibody JSB-1 to determine the prevalence of PgP expression and its relationship with chemotherapy exposure. Of the 42 patients, 31 (74%) had detectable PgP. No relationship was found between PgP expression, patient age, duration of disease or stage. Moderate and strong intensity staining was found in 22% of untreated patients versus 56% patients treated with chemotherapy (p<0.05). Temporal fluctuations in P-glycoprotein staining intensity was seen in 6 of 7 cases which paralleled the initiation or withdrawal of the therapy.
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The evolution of flow cytometry from a research tool to a pivotal technology for clinical diagnostic purposes has required significant efforts to standardize methods. The great advantage of flow cytometry is that it's applications are highly amenable to standardization. Here, we review the efforts that have been made for flow cytometric applications in four major fields of clinical cell analysis: CD4+ T-cell enumeration, CD34+ hematopoietic stem and progenitor cell enumeration, screening for the HLA-B27 antigen and leukemia/lymphoma immunophenotyping. These standardization efforts have been parallelled by the establishment of external quality assessment (EQA) schemes in many countries worldwide. The goal of these EQA exercises has been primarily educa-tional, but their results will increasingly serve as a basis for laboratory accreditation. This important development requires that the EQA schemes, in particular the quality of the distributed samples and the procedures for evaluating the results, meet the highest standards.
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Citometría de Flujo/métodos , Antígenos CD34/análisis , Recuento de Linfocito CD4 , Citometría de Flujo/normas , Antígeno HLA-B27/análisis , Células Madre Hematopoyéticas/citología , Humanos , Inmunofenotipificación , Leucemia/inmunología , Linfoma/inmunologíaRESUMEN
Flow cytometric enumeration of CD34+ hematopoietic stem and progenitor cells (HPC) is widely used for evaluation of graft adequacy of peripheral blood stem cell grafts, and is also useful in planning the apheresis sessions necessary to obtain these grafts. The state-of-the-art method to enumerate CD34+ cells makes use of a multiparameter definition of HPC based on their light scatter characteristics and dim expression of CD45, and the use of counting beads to derive the concentration of CD34+ cells directly from the flow cytometric assessment. This method can be extended with a viability stain and additional markers for further immunological characterization of CD34+ cells, and has been successfully implemented in multicenter trials. Thus, the lower threshold of a safe HPC graft in terms of short- and long-term hematopoiesis may be more accurately defined.
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Antígenos CD34/análisis , Células Madre Hematopoyéticas/química , Animales , Recuento de Células , Citometría de Flujo , Humanos , Inmunofenotipificación , Antígenos Comunes de Leucocito/análisis , Control de CalidadRESUMEN
Groups of C57Bl/6J mice, fed either a cis (C-Diet) or trans diet (T-Diet) were milked without preconditioning at 6, 8, 10 and 12 days postpartum. On day 10, groups of mice were also milked 4, 6 and 18 h after separation of the pups. Except for the 18-h separation, all T-Diet fed animals produced milk of lower fat content than did the C-Diet animals (P < 0.001) throughout the lactation period measured. In the C-Diet mice, the 6-h separation period resulted in a decrease (P < or = 0.03) in fat, but the diet-depressed milk fat of T-Diet animals was not decreased further until the 18-h separation period. Milk volume increased as lactation progressed and was greatly increased as a result of preconditioning (P < or = 0.001), even at 4 h of separation when fat was not reduced, and was always greater for T-Diet animals. Within diet groups, fatty acid composition was similar throughout the lactation period studied and was not affected by preconditioning except in the 18-h separation period, when de novo fatty acids were significantly reduced (P < or = 0.05). The data are consistent with the hypothesis that preconditioning results in lowered milk fat values and that preconditioning techniques can explain discrepancies in literature values for murine milk fat.
Asunto(s)
Animales Lactantes/fisiología , Grasas de la Dieta/administración & dosificación , Ácidos Grasos/administración & dosificación , Lactancia/fisiología , Metabolismo de los Lípidos , Leche/metabolismo , Animales , Ácidos Grasos/metabolismo , Femenino , Ratones , Ratones Endogámicos C57BLRESUMEN
INTRODUCTION: Despite the advancements in instrumentation within hematology laboratories, there is still a need for review of a peripheral blood film (PBF). For a thorough PBF evaluation, it is critical that a well spread and stained film is available. METHODS: In this study, we evaluated an automatic slide maker/stainer (DxH-SMS, Beckman Coulter) compared with manually prepared blood films on 124 normal and abnormal samples. The primary goal of the study was to determine whether or not the DxH-SMS was able to consistently and reproducibly prepare and stain blood films of exemplary quality, without carryover between specimens. Additionally, repeatability of white blood cell distribution, comparability of morphology to reference methodologies, and grading of acceptance criteria outlined in the CLSI document H20-A2 were assessed. RESULTS: Carryover was not an issue and repeatability was within expected limits. There was excellent agreement of the 5-part differential between the automated blood films made by the DxH-SMS compared with the manually prepared reference blood film. There was no difference in identification and enumeration of blasts, variant lymphocytes, or nucleated red blood cells (P < 0.05). Red cell morphology showed excellent agreement. CONCLUSION: Blood films prepared by the DxH-SMS are of excellent quality, reproducible, and compare well with manually prepared slides. Introduction to our laboratory has improved and standardized slide quality.