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1.
Radiologia ; 56(2): 136-47, 2014.
Artículo en Español | MEDLINE | ID: mdl-22709791

RESUMEN

PURPOSE: To implement in-phase and out-of-phase (IP/OP) techniques with Magnetization-Prepared Gradient Recalled Echo (MP-GRE) and to evaluate the feasibility and diagnostic image quality among pre and post-optimized MP-GRE sequences, including patients unable to cooperate with breath-hold requirements. MATERIALS AND METHODS: Institutional review board approval with waiver of informed consent was obtained for this HIPAA-compliant retrospective study. Two groups of patients were included in the study, before and after optimization of MP-GRE parameters, with seventy-three (24 noncooperative/49 cooperative) and sixty-four (22 noncooperative/42 cooperative) consecutive patients, respectively. The motion-insensitive sequence used in this study was a single-shot 2D MP-GRE. Two radiologists qualitatively evaluated the sequences to identify the presence of phase cancellation artifact in OP images and to determine image quality, extent of artifacts (respiratory ghosting, bounce-point artifact, spatial misregistration and pixel graininess) and lesion conspicuity on the various sequences. The ability to visually detect liver steatosis and fatty adrenal adenomas was evaluated. Qualitative analyses were compared using the Wilcoxon and Mann-Whitney tests. RESULTS: There were statistically significant differences between all MP-GRE sequences concerning phase cancellation artifact (P<.0001) which was present in MP-GRE OP sequences and negligible to absent in the pre (IP1) and post-optimized (IP2) MP-GRE IP sequences, respectively, in all patients. Bounce point artifacts were significantly more pronounced in MP-GRE IP1 (P<.0001). Spatial misregistration was slightly more prominent in noncooperative patients with MP-GRE IP2 (P=.0027). MP-GRE OP and MP-GRE IP2 showed significantly higher overall image quality (P<.0001). MP-GRE sequences subjectively identified hepatic steatosis (n=20) and adrenal adenomas (n=5) based on signal loss from IP to OP sequence. CONCLUSION: Single shot IP/OP MP-GRE is feasible and allows motion resistant imaging with adequate diagnostic image quality. This technique is able to provide IP and OP information in patients unable to suspend respiration.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Artefactos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
2.
Eur Radiol ; 23(11): 3087-93, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23732689

RESUMEN

OBJECTIVE: Evaluate the image quality and diagnostic performance of a free-breathing 3D-gradient-echo sequence with radial acquisition (rGRE) compared with a Cartesian breath-hold 3D-GRE (cGRE) sequence on hepatobiliary phase MRI in patients with breath-holding difficulties. METHODS: Twenty-eight consecutive patients (15 males; mean age 61 ± 11.9 years) were analysed in this retrospective IRB-approved study. Breath-holding difficulties during gadoxetate-disodium-enhanced liver MRI manifested as breathing artefacts during dynamic-phase imaging. MRI included axial and coronal cGRE and a radially sampled rGRE sequence during the hepatobiliary phase. Two radiologists independently evaluated cGRE and rGRE images for image quality, liver lesion detection and conspicuity, and bile duct conspicuity on a four-point scale. RESULTS: Liver edge sharpness was significantly higher on rGRE images (P < 0.001). Overall image quality was slightly but significantly higher for rGRE than for cGRE (P < 0.001 and P = 0.039). Bile duct conspicuity scores of rGRE and cGRE were not significantly different. Sensitivity for detection of the 26 liver lesions was similar for rGRE and cGRE (81-77 % and 73-77 %, P = 0.5 and 1.0). Lesion conspicuity scores were significantly higher for rGRE for one reader (P = 0.012). CONCLUSION: In patients with breath-holding difficulties, overall image quality and liver lesion conspicuity on hepatobiliary phase MRI can be improved using the rGRE sequence. KEY POINTS: • Patients with diminished breath-holding capacities present a major challenge in abdominal MRI. • A free-breathing sequence for hepatobiliary-phase MRI can improve image quality. • Further advances are needed to reduce acquisition time of the free-breathing gradient-echo sequence.


Asunto(s)
Enfermedades de las Vías Biliares/diagnóstico , Contencion de la Respiración , Imagen Eco-Planar/métodos , Gadolinio DTPA , Hepatopatías/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Artefactos , Medios de Contraste , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos
3.
J Exp Med ; 193(1): 61-71, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11136821

RESUMEN

The Src homology 2 domain-containing inositol 5'-phosphatase (SHIP) is recruited to immunoreceptor tyrosine-based inhibition motif (ITIM)-containing proteins, thereby suppressing phosphatidylinositol 3-kinase (PI 3-kinase)-dependent pathways. The role of SHIP in phagocytosis, a PI 3-kinase-dependent pathway, is unknown. Overexpression of SHIP in macrophages led to an inhibition of phagocytosis mediated by receptors for the Fc portion of IgG (Fc gamma Rs). In contrast, macrophages expressing catalytically inactive SHIP or lacking SHIP expression demonstrated enhanced phagocytosis. To determine whether SHIP regulates phagocytosis mediated by receptors that are not known to recruit ITIMs, we determined the effect of SHIP expression on complement receptor 3 (CR3; CD11b/CD18; alpha(M)beta(2))-dependent phagocytosis. Macrophages overexpressing SHIP demonstrated impaired CR3-mediated phagocytosis, whereas macrophages expressing catalytically inactive SHIP demonstrated enhanced phagocytosis. CR3-mediated phagocytosis in macrophages derived from SHIP(-/-) mice was up to 2.5 times as efficient as that observed in macrophages derived from littermate controls. SHIP was localized to Fc gamma R- and CR3-containing phagocytic cups and was recruited to the cytoskeleton upon clustering of CR3. In a transfected COS cell model of activation-independent CR3-mediated phagocytosis, catalytically active but not inactive SHIP also inhibited phagocytosis. We conclude that PI 3-kinase(s) and SHIP regulate multiple forms of phagocytosis and that endogenous SHIP plays a role in modulating beta(2) integrin outside-in signaling.


Asunto(s)
Antígeno de Macrófago-1/metabolismo , Fagocitosis/inmunología , Monoéster Fosfórico Hidrolasas/inmunología , Receptores de IgG/metabolismo , Animales , Células COS , Células Cultivadas , Citoesqueleto/inmunología , Ratones , Ratones Noqueados , Fagocitosis/fisiología , Fagosomas/inmunología , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas , Monoéster Fosfórico Hidrolasas/genética , Transfección , Dominios Homologos src
4.
J Exp Med ; 191(3): 515-28, 2000 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-10662797

RESUMEN

Ingestion of opsonized pathogens by professional phagocytes results in the generation and release of microbicidal products that are essential for normal host defense. Because these products can result in significant tissue injury, phagocytosis must be regulated to limit damage to the host while allowing for optimal clearance and destruction of opsonized pathogens. To pursue negative regulation of phagocytosis, we assessed the effect of the Src kinase family member, Fgr, on opsonin-dependent phagocytosis by mouse macrophages. We chose Fgr because it is present in high concentrations in circulating phagocytes but is not essential for Fcgamma receptor-mediated ingestion by mouse macrophages. Although expression of Fgr both in a macrophage cell line and in primary macrophages significantly attenuates ingestion mediated by Fcgamma receptors and CR3, it does not affect macropinocytosis or receptor-mediated endocytosis. This selective effect of Fgr is independent of its tyrosine kinase function. After Fcgamma receptor cross-linking, Fgr becomes associated with the immunoreceptor tyrosine-based inhibition motif (ITIM)-containing receptor, SIRPalpha (a member of the signal-regulatory protein family, also known as Src homology 2 domain-containing protein tyrosine phosphatase [SHP] substrate 1 [SHPS-1], brain immunoglobulin-like molecule with tyrosine-based activation motifs [BIT], and P84) and potentiates the association of the phosphatase SHP-1 with SIRPalpha. This association is responsible, at least in part, for decreasing positive signaling essential for optimal phagocytosis. These data demonstrate an important negative regulatory role for this Src kinase family member and suggest that this homeostatic function must be overcome for optimal uptake and clearance of opsonized pathogens.


Asunto(s)
Macrófagos/fisiología , Familia-src Quinasas/fisiología , Animales , Línea Celular , Regulación hacia Abajo/efectos de los fármacos , Inmunoglobulina G/farmacología , Ratones , Fagocitosis , Pinocitosis/efectos de los fármacos , Proteínas Tirosina Fosfatasas/metabolismo , Receptores Inmunológicos/fisiología , Transducción de Señal , Dominios Homologos src , Familia-src Quinasas/deficiencia , Familia-src Quinasas/farmacología
5.
AJNR Am J Neuroradiol ; 39(2): 311-316, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29284598

RESUMEN

BACKGROUND AND PURPOSE: Intracranial pressure is estimated invasively by using lumbar puncture with CSF opening pressure measurement. This study evaluated displacement encoding with stimulated echoes (DENSE), an MR imaging technique highly sensitive to brain motion, as a noninvasive means of assessing intracranial pressure status. MATERIALS AND METHODS: Nine patients with suspected elevated intracranial pressure and 9 healthy control subjects were included in this prospective study. Controls underwent DENSE MR imaging through the midsagittal brain. Patients underwent DENSE MR imaging followed immediately by lumbar puncture with opening pressure measurement, CSF removal, closing pressure measurement, and immediate repeat DENSE MR imaging. Phase-reconstructed images were processed producing displacement maps, and pontine displacement was calculated. Patient data were analyzed to determine the effects of measured pressure on pontine displacement. Patient and control data were analyzed to assess the effects of clinical status (pre-lumbar puncture, post-lumbar puncture, or control) on pontine displacement. RESULTS: Patients demonstrated imaging findings suggesting chronically elevated intracranial pressure, whereas healthy control volunteers demonstrated no imaging abnormalities. All patients had elevated opening pressure (median, 36.0 cm water), decreased by the removal of CSF to a median closing pressure of 17.0 cm water. Patients pre-lumbar puncture had significantly smaller pontine displacement than they did post-lumbar puncture after CSF pressure reduction (P = .001) and compared with controls (P = .01). Post-lumbar puncture patients had statistically similar pontine displacements to controls. Measured CSF pressure in patients pre- and post-lumbar puncture correlated significantly with pontine displacement (r = 0.49; P = .04). CONCLUSIONS: This study establishes a relationship between pontine displacement from DENSE MR imaging and measured pressure obtained contemporaneously by lumbar puncture, providing a method to noninvasively assess intracranial pressure status in idiopathic intracranial hypertension.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Seudotumor Cerebral/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Punción Espinal
6.
J Clin Oncol ; 13(5): 1073-9, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7738613

RESUMEN

PURPOSE: To evaluate the significance of molecular marker-positive cells in a cohort of non-Hodgkin's lymphoma (NHL) patients undergoing high-dose chemotherapy and autologous peripheral-blood stem-cell transplantation (PBSCT). PATIENTS AND METHODS: Twenty-eight PBSC transplants have been performed in 24 patients with poor-prognosis NHL. Molecular analysis of the t(14;18) (q32;q21) translocation (bcl-2/immunoglobulin [Ig] heavy-chain joining locus [JH] fusion) or antigen receptor gene rearrangements was performed to determine the presence of lymphoma cells at presentation, in PBSC harvests, and before and after autologous PBSCT. Kaplan-Meier estimates of survival and Cox regression analyses were used to test the effect of bone marrow involvement, tumor-cell contamination of PBSCs, disease stage, and chemotherapy sensitivity at transplantation, and presence of marker-positive cells post-PBSCT on disease-free and overall survival. RESULTS: Thirteen of 24 patients (54%) are alive following PBSCT at a median follow-up time of 654 days (range, 193 to 1,908). Nine patients are in complete remission (CR) at day 216 to 1,799 (median, 805) and four are alive following relapse (day 440, 573, 1,188, and 1,908). Eleven patients (46%) have died: three of transplant-related complications at day 0, 1, and 13, and eight of recurrent disease (day 132 to 1,330; median, 451). Longitudinal marker studies post-PBSCT showed that of 16 relapse events, 13 (81%) were positive for the lymphoma marker at or before clinically documented relapse. Marker studies became negative post-PBSCT in nine of nine patients who entered and remained in CR. Disease-free survival (DFS) was significantly shortened in patients in whom marker-positive cells were detected in serial samples posttransplantation (P = .006). Cox regression analysis showed that patients in this group had a 24 times higher risk of relapse (P = .03). CONCLUSION: The results show that the reappearance or persistence of marker-positive cells after autologous PBSCT is strongly associated with relapse.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/terapia , Translocación Genética/genética , Adulto , Southern Blotting , Estudios de Cohortes , Terapia Combinada , Ciclofosfamida/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Marcadores Genéticos , Humanos , Linfoma no Hodgkin/genética , Linfoma no Hodgkin/mortalidad , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , Pronóstico , Recurrencia , Análisis de Regresión , Análisis de Supervivencia , Resultado del Tratamiento
7.
Exp Hematol ; 18(5): 442-7, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1970963

RESUMEN

We used single high doses of cyclophosphamide (4 g/m2) to produce rebound increases in peripheral blood (PB) stem cells (PBSC) during recovery from myelosuppression, enabling their collection by apheresis for later autotransplantation. Thirty-three courses of cyclophosphamide were given to 30 patients with malignant lymphoma, multiple myeloma, or solid tumors. The neutrophil count was less than 0.5 x 10(9)/liter for a mean of 6.9 days (median 7 days), and fever occurred in 17 of 33 courses. Positive blood cultures occurred in two patients, one of whom died. The mean peak level of PB granulocyte-macrophage colony-forming units (CFU-GM) was 1517 x 10(3)/liter (median 2447 x 10(3)/liter), a 14-fold increase above the mean in normal subjects. The peak occurred at a mean of 16.6 days (median 16 days) after cyclophosphamide, generally coinciding with the time to reach 1.0 x 10(9) neutrophils per liter. Normal or minimally involved bone marrow and a rapid rise in leukocyte count during recovery were independent variables correlated to the peak of the rebound increase in PB CFU-GM levels. Previous chemotherapy and the duration of neutropenia were additional independent variables in the group with peak PB CFU-GM levels of greater than 1000 x 10(3)/liter. The mean total CFU-GM collected after a mean of five aphereses was 43.8 x 10(4)/kg body weight (BW) (median 35.5 x 10(4)/kg BW), significantly correlated with the mononuclear cell yield. We conclude that single 4 g/m2 doses of cyclophosphamide effectively produce high levels of PBSC, particularly but not exclusively in patients with normal or minimally involved bone marrow and who have not had intensive recent chemotherapy.


Asunto(s)
Ciclofosfamida/administración & dosificación , Células Madre Hematopoyéticas/patología , Linfoma/sangre , Mieloma Múltiple/sangre , Adulto , Eliminación de Componentes Sanguíneos , Recuento de Células , Ensayo de Unidades Formadoras de Colonias , Ciclofosfamida/farmacología , Ciclofosfamida/uso terapéutico , Femenino , Granulocitos/patología , Trasplante de Células Madre Hematopoyéticas , Humanos , Recuento de Leucocitos , Linfoma/tratamiento farmacológico , Macrófagos/patología , Masculino , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Recuento de Plaquetas
8.
Bone Marrow Transplant ; 11(1): 15-20, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8381694

RESUMEN

Twenty-seven patients with non-Hodgkin's lymphoma (NHL) have undergone peripheral blood stem cell (PBSC) harvesting for autologous transplantation (Tx). A molecular marker was found at presentation in 23/27 patients. Immunoglobulin heavy chain (IgH) or T cell receptor beta (TCR beta) rearrangements were detected by Southern blotting or the polymerase chain reaction (PCR) in 13 patients; PCR detected the bcl-2/JH fusion in 10 patients. Fifteen autologous PBSC transplants have been performed in 11 patients. In 5/11 patients, the marker was present in at least one PBSC collection (in four patients, every PBSC collection was positive). Survival data are available for nine patients (two early deaths); three patients relapsed and died (221 - 930 d), one is alive and in relapse (354 + d) and five are alive and in complete remission (330 - 1290 + d). These findings suggest that tumour cell contamination of PBSC harvests is not uncommon. Whether these cells are clonogenic and contribute to disease relapse remains to be elucidated. The presence of residual disease at the time of transplantation and the reappearance (or persistence) of marker positive cells post-transplantation both appear to be poor prognostic factors for disease-free survival.


Asunto(s)
Trasplante de Médula Ósea/patología , Linfoma no Hodgkin/cirugía , Adulto , Secuencia de Bases , Biomarcadores de Tumor , Células Sanguíneas/inmunología , Células Sanguíneas/patología , Purgación de la Médula Ósea , Trasplante de Médula Ósea/efectos adversos , Trasplante de Médula Ósea/métodos , Clonación Molecular , ADN de Neoplasias/genética , Femenino , Reordenamiento Génico de Cadena Pesada de Linfocito B , Reordenamiento Génico de la Cadena beta de los Receptores de Antígenos de los Linfocitos T , Células Madre Hematopoyéticas/inmunología , Células Madre Hematopoyéticas/patología , Humanos , Linfoma no Hodgkin/genética , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Células Neoplásicas Circulantes/inmunología , Células Neoplásicas Circulantes/patología , Reacción en Cadena de la Polimerasa , Pronóstico , Trasplante Autólogo
9.
Bone Marrow Transplant ; 9(1): 11-7, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1347478

RESUMEN

Sixty patients with malignancy were enrolled in a study of high-dose chemotherapy and peripheral blood stem cell transplantation (PBSCT). Stem cells were harvested prior to PBSCT using high-dose cyclophosphamide (CY) mobilization (4 or 7 g/m2) with collection of a median of 4.6 x 10(8)/kg mononuclear cells (range 0.2-9.5) and 21.6 x 10(4)/kg colony forming unit-granulocyte/macrophage (CFU-GM) (range 0.1-220). Forty-seven patients were mobilized once, 11 required two cycles and two required three cycles. Eight patients (13%) failed to reach the optimum CFU-GM target (greater than 15 x 10(4)/kg) following CY mobilization. A number of factors identified those patients who were likely to achieve optimum CFU-GM collections with CY mobilization. These included the use of the higher CY mobilization dose, a longer interval from last chemotherapy cycle to mobilization, and a higher premobilization bone marrow CFU-GM level. Patient's age, the degree of bone marrow infiltration, the nature of disease or the number of pre-mobilization chemotherapeutic cycles did not affect the ability to collect optimum CFU-GM numbers. Whilst the mobilization procedure was associated with moderate non-hematologic toxicity, significant hematological morbidity was observed primarily in patients mobilized using the 7 g/m2 dose. Refinements to the protocol, in particular the use of hematopoietic growth factors, are currently under investigation.


Asunto(s)
Células Sanguíneas/trasplante , Trasplante de Médula Ósea/métodos , Ciclofosfamida/administración & dosificación , Neoplasias/cirugía , Adolescente , Adulto , Anciano , Células Sanguíneas/efectos de los fármacos , Células Sanguíneas/patología , Eliminación de Componentes Sanguíneos , Terapia Combinada , Femenino , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/patología , Humanos , Linfoma/sangre , Linfoma/tratamiento farmacológico , Linfoma/cirugía , Masculino , Persona de Mediana Edad , Mieloma Múltiple/sangre , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/cirugía , Neoplasias/sangre , Neoplasias/tratamiento farmacológico , Trasplante Autólogo
10.
Cancer Genet Cytogenet ; 16(1): 45-8, 1985 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-3855689

RESUMEN

The breakpoints of a complex three-way translocation involving chromosomes X, #15, and #17 were resolved in a case of acute promyelocytic leukemia (APL). It is now apparent that similar cases of variant chromosome translocations are found in both chronic granulocytic leukemia (CGL) and APL. The morphological and clinical findings in this case emphasize the variability found in some cases of APL.


Asunto(s)
Cromosomas Humanos 13-15 , Cromosomas Humanos 16-18 , Leucemia Mieloide Aguda/genética , Translocación Genética , Cromosoma X , Femenino , Humanos , Persona de Mediana Edad
11.
Cancer Genet Cytogenet ; 44(1): 99-105, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2293884

RESUMEN

We present two cases in which translocations involving 21q22 were found at presentation in acute nonlymphocytic leukemia (ANLL). The first of these translocations, t(3;21)(q26-q27;q22), is previously unknown in ANLL, but appears indistinguishable from that reportedly associated with Philadelphia-positive chronic myelogenous leukemia. The second case involves t(15;21)(q21-q22;q22), a translocation previously undescribed in ANLL. Both of these exchanges involve 21q22 plus another chromosome region associated with leukemogenesis. We attempted to interrelate these cytogenetic data with the oncogenic significance of 21q22.


Asunto(s)
Cromosomas Humanos Par 21 , Leucemia Mieloide Aguda/genética , Translocación Genética , Bandeo Cromosómico , Femenino , Humanos , Cariotipificación , Leucemia Mielomonocítica Aguda/genética , Masculino , Persona de Mediana Edad
12.
Cancer Genet Cytogenet ; 56(2): 255-62, 1991 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-1756471

RESUMEN

A 21-year-old male presented with a large mediastinal mass and a white cell count of 420 x 10(9)/L. A diagnosis of acute lymphoblastic leukemia (ALL) was made, with 90% of cells in the bone marrow (BM) and 99% in the peripheral blood (PB) being lymphoblasts (FAB L1). Cytogenetic analysis of these cells revealed a rare variant of the t(4;11) translocation involving chromosome arm 11p rather than 11q, namely t(4;11)(q21;p14-15). The standard form of the (4;11) translocation has been associated with leukemias with mixed-lineage phenotypes. Three cases of ALL with t(4q;11p) have previously been reported. One of these cases showed phenotypic heterogeneity involving myeloid and lymphoid lineages. The leukemia reported here also exhibits lymphoid/myeloid features. Immunophenotyping of the blasts showed that most of the cells were positive for CD2, CD5, CD7, CD10 (CALLA), CD34, and HLA-DR. A significant proportion of the cells expressed CD33. These results suggest a biphenotypic rather than a biclonal disease. Molecular analysis showed rearrangement of both immunoglobulin heavy-chain genes (JH) and of a single allele of the T-cell receptor (TCR) gamma 1 gene, while retaining germline TCR beta genes.


Asunto(s)
Cromosomas Humanos Par 11 , Cromosomas Humanos Par 4 , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocación Genética , Adulto , Antígenos CD/análisis , Reordenamiento Génico/genética , Reordenamiento Génico de Linfocito T , Antígenos HLA-DR/análisis , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Inmunofenotipificación , Cariotipificación , Masculino , Receptores de Antígenos de Linfocitos T/genética
13.
Cancer Chemother Pharmacol ; 16(2): 194-7, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3948305

RESUMEN

Fifteen patients receiving oral melphalan (4.2-5.3 mg/m2) for a variety of neoplastic disorders were studied. Ten patients received the drug on separate occasions, with and without a standardized breakfast. Eight of these patients also received an IV bolus dose (5 mg/m2) to determine bioavailability. Serial melphalan plasma samples were taken over 5 h after administration and assayed by high-performance liquid chromatography. The median area under the curve (AUC) when taken fasting was 179 (range 95-336) ng X h X ml-1, and when taken with food, 122 (47-227) ng X h X ml-1, the median reduction being 39% (P less than 0.01). In one patient, who died before completing the study, the drug was not detectable at all after being taken with food. In the eight patients who were also given IV melphalan, the median terminal melphalan half-life (57 min, range 38-71) was no different from its oral half-life [55 (27-104) min fasting; 55 (30-72) min with food] (P greater than 0.1). In these patients bioavailability was 85% (26-96)% when the drug was taken fasting and 58% (7-99)% when taken with food (P less than 0.025). Median clearance following IV administration was 362 ml/min/m2 (range 104-694). It was found that the melphalan level in a single plasma sample drawn 1.5 h after administration was highly predictive of oral melphalan AUC (rs = 0.915, P less than 0.1). This study suggests that to ensure optimum absorption of the drug, melphalan should not be taken with food.


Asunto(s)
Alimentos , Melfalán/metabolismo , Absorción , Administración Oral , Anciano , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Ayuno , Femenino , Humanos , Inyecciones Intravenosas , Cinética , Masculino , Melfalán/administración & dosificación , Melfalán/sangre , Melfalán/uso terapéutico , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico
14.
Cancer Chemother Pharmacol ; 22(4): 348-52, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3168148

RESUMEN

The renal clearance of melphalan and the fraction unbound in plasma were determined after intravenous infusion of 5 mg/m2 over 5 min in nine patients with cancer to obtain information regarding the mechanism of renal handling of melphalan. Four of the patients underwent bone marrow transplantation and also received an IV dose of 220 mg/m2. Total melphalan clearance after the 5 mg/m2 dose ranged from 66.0 to 272 ml/min per m2; the percentage of the dose excreted unchanged in urine, from 2.5% to 92.8%; renal clearance, from 4.1 to 188 ml/min per m2; the fraction unbound in plasma, from 0.0598 to 0.460; and t1/2 beta, from 39.4 to 84.3 min. Unbound melphalan clearance and renal clearance calculated from the unbound fraction in plasma for each patient ranged from 441 to 3356 ml/min per m2 and 15 to 961 ml/min per m2 respectively and were not related to serum albumin, serum creatinine or creatinine clearance. The percentage of the dose excreted and melphalan renal clearance were not related to urine flow. There was evidence of active secretion of melphalan in the kidney an possible reabsorption. There were no significant paired differences in melphalan disposition between the high- and low-dose studies. Highly variable renal clearance involving active secretion may contribute in part to large interpatient differences in the total plasma clearance of melphalan in patients with cancer.


Asunto(s)
Riñón/metabolismo , Melfalán/farmacocinética , Adulto , Anciano , Femenino , Humanos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Unión Proteica
15.
Cancer Chemother Pharmacol ; 20(3): 256-8, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3315285

RESUMEN

Melphalan uptake in the intestine has recently been shown to be an energy-dependent process which is affected by metabolic inhibitors. It is therefore theoretically possible that amino acids in food could reduce melphalan absorption by competing for uptake at the sites of absorption in the intestine. Since L-leucine has been shown to be the most potent inhibitor of melphalan transport into cells in vitro, this amino acid was chosen for the present study in patients. Oral melphalan (4.5 +/- 0.5 mg/m2) was given to ten fasting patients with and without a 2-g oral dose of L-leucine on separate randomized occasions at least 1 week apart. Melphalan plasma levels were measured by high-performance liquid chromatography (HPLC) for 5-h after dosing. L-Leucine plasma levels were measured by HPLC before and at 1 h after dosing. The area under the curve for melphalan was lower in seven of the patients after L-leucine. Plasma L-leucine levels 1 h after melphalan administration were 15.4 +/- 3.7 micrograms/ml fasting and 35.4 +/- 5.2 micrograms/ml after L-leucine. The results indicate that L-leucine can reduce plasma melphalan levels in some patients, probably through a reduction in absorption of the drug from the gastrointestinal tract. However, the effect, like that of food, is highly variable.


Asunto(s)
Leucina/farmacología , Melfalán/farmacocinética , Administración Oral , Anciano , Cromatografía Líquida de Alta Presión , Ensayos Clínicos como Asunto , Ayuno , Femenino , Humanos , Absorción Intestinal , Leucina/administración & dosificación , Leucina/sangre , Masculino , Melfalán/administración & dosificación , Melfalán/sangre , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Distribución Aleatoria , Factores de Tiempo
16.
Pathology ; 16(4): 424-30, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6522108

RESUMEN

Familial antithrombin III (AT III) deficiency, with mesenteric venous thrombosis, is reported in an Australian family. Antithrombin III was assayed chromogenically, fluorometrically, and immunologically. The deficiency was further analysed using crossed-immunoelectrophoresis. It is suggested that when AT III deficiency is suspected, both a functional and an immunological assay should be performed.


Asunto(s)
Deficiencia de Antitrombina III , Oclusión Vascular Mesentérica/genética , Adolescente , Antitrombina III/genética , Femenino , Humanos , Inmunoelectroforesis Bidimensional , Masculino , Oclusión Vascular Mesentérica/sangre , Persona de Mediana Edad , Linaje , Trombosis/sangre , Trombosis/genética
17.
Pathology ; 13(1): 79-95, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7012767

RESUMEN

Four cases of node-based T cell lymphoma are presented. The tumours had 2 distinct morphologic patterns. Two cases showed a polymorphous proliferation of pleomorphic lymphoid cells, small lymphocytes, epithelioid cells and arborizing small vessels while the others displayed a monomorphous infiltrate of large atypical lymphoid cells characterized by granular nuclei with numerous tortuous folds to produce a 'squiggly' appearance. One case showed a progression from one histological pattern to the other. Confirmation of the T cell nature of these lymphomas was based on the demonstration of E-rosette formation by morphologically atypical lymphoid cells which also stained positive for acid alpha-naphthyl acetate esterase activity. The patients had an average age of 52 yr and presented with a variable distribution of lymphadenopathy and a predominance of extranodal involvement. Two cases disclosed hypergammaglobulinaemia, one of whom had a paraproteinaemia of IgM-k type. All patients responded poorly to standard combination chemotherapy, 2 expiring 48 and 53 mth after onset of symptoms.


Asunto(s)
Ganglios Linfáticos/citología , Linfoma/clasificación , Linfocitos T/inmunología , Adulto , Anciano , Ciclofosfamida/uso terapéutico , Femenino , Humanos , Técnicas para Inmunoenzimas , Neoplasias Hepáticas/secundario , Linfoma/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Receptores de Complemento , Receptores Fc , Vinblastina/uso terapéutico
18.
Pathology ; 13(3): 609-14, 1981 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6946388

RESUMEN

Buffy coat cells were collected by leukapheresis from 14 patients with C.G.L. and one patient with M.M.M. Six of the C.G.L. patients had received busulphan at intervals varying between 401 and 38 d before leukapheresis. Significantly more CFUc's could be collected per leukapheresis in untreated patients and in those patients not treated within 105 d prior to leukapheresis. Survival of CFUc's following freezing was significantly less in the 3 most recently treated patients. These results suggest that in C.G.L. patients recently treated with busulphan, both the number of CFUc's in the peripheral blood and the ability of these cells to survive the freeze thaw process are reduced. However, sufficient CFUc's could theoretically be collected, stored and recovered post-thaw from one leukapheresis to allow complete haematopoietic restoration in all but 2 patients.


Asunto(s)
Busulfano/farmacología , Células Madre Hematopoyéticas , Leucaféresis , Leucemia Mieloide/sangre , Adulto , Anciano , Conservación de la Sangre , Busulfano/uso terapéutico , Niño , Ensayo de Unidades Formadoras de Colonias , Femenino , Congelación , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Leucemia Mieloide/tratamiento farmacológico , Leucemia Mieloide/terapia , Masculino , Persona de Mediana Edad
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