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1.
Phys Rev Lett ; 132(6): 065107, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38394599

RESUMO

The perturbed ion temperature and toroidal flow were measured in rotating neoclassical tearing modes (NTM) in a tokamak for the first time. These toroidally and radially resolved profiles were obtained by impurity ion spectroscopy in a 2,1 NTM in DIII-D. In agreement with drift-kinetic simulations, the electron temperature profile is flat, while the ion temperature gradient is restored across the magnetic island O point in the presence of fast ions; the perturbed flow has minima in the O points and maxima at the X points. These measurements provide the first confirmation of the theoretically expected ion temperature and flow response to a magnetic island needed to predict the NTM onset threshold scaling for ITER and other future tokamaks.

2.
Phys Rev Lett ; 131(7): 075101, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37656860

RESUMO

The fusion-born alpha particle heating in magnetically confined fusion machines is a high priority subject for studies. The self-heating of thermonuclear fusion plasma by alpha particles was observed in recent deuterium-tritium (D-T) experiments on the joint European torus. This observation was possible by conducting so-called "afterglow" experiments where transient high fusion yield was achieved with neutral beam injection as the only external heating source, and then termination of the heating at peak performance. This allowed the first direct evidence for electron heating of plasmas by fusion-born alphas to be obtained. Interpretive transport modeling of the relevant D-T and reference deuterium discharges is consistent with the alpha particle heating observation.

3.
Metrologia ; 552018.
Artigo em Inglês | MEDLINE | ID: mdl-31080297

RESUMO

The International Committee for Weights and Measures (CIPM), at its meeting in October 2017, followed the recommendation of the Consultative Committee for Units (CCU) on the redefinition of the kilogram, ampere, kelvin and mole. For the redefinition of the kelvin, the Boltzmann constant will be fixed with the numerical value 1.380 649 × 10-23 J K-1. The relative standard uncertainty to be transferred to the thermodynamic temperature value of the triple point of water will be 3.7 × 10-7, corresponding to an uncertainty in temperature of 0.10 mK, sufficiently low for all practical purposes. With the redefinition of the kelvin, the broad research activities of the temperature community on the determination of the Boltzmann constant have been very successfully completed. In the following, a review of the determinations of the Boltzmann constant k, important for the new definition of the kelvin and performed in the last decade, is given.

4.
Phys Rev Lett ; 118(26): 265001, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28707924

RESUMO

In this Letter we present data from experiments on the National Spherical Torus Experiment Upgrade, where it is shown for the first time that small amounts of high pitch-angle beam ions can strongly suppress the counterpropagating global Alfvén eigenmodes (GAE). GAE have been implicated in the redistribution of fast ions and modification of the electron power balance in previous experiments on NSTX. The ability to predict the stability of Alfvén modes, and developing methods to control them, is important for fusion reactors like the International Tokamak Experimental Reactor, which are heated by a large population of nonthermal, super-Alfvénic ions consisting of fusion generated α's and beam ions injected for current profile control. We present a qualitative interpretation of these observations using an analytic model of the Doppler-shifted ion-cyclotron resonance drive responsible for GAE instability which has an important dependence on k_{⊥}ρ_{L}. A quantitative analysis of this data with the hym stability code predicts both the frequencies and instability of the GAE prior to, and suppression of the GAE after the injection of high pitch-angle beam ions.

5.
Philos Trans A Math Phys Eng Sci ; 374(2064): 20150048, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26903104

RESUMO

Using exceptionally accurate measurements of the speed of sound in argon, we have made estimates of the difference between thermodynamic temperature, T, and the temperature estimated using the International Temperature Scale of 1990, T90, in the range 118 K to 303 K. Thermodynamic temperature was estimated using the technique of relative primary acoustic thermometry in the NPL-Cranfield combined microwave and acoustic resonator. Our values of (T-T90) agree well with most recent estimates, but because we have taken data at closely spaced temperature intervals, the data reveal previously unseen detail. Most strikingly, we see undulations in (T-T90) below 273.16 K, and the discontinuity in the slope of (T-T90) at 273.16 K appears to have the opposite sign to that previously reported.

6.
Adv Mar Biol ; 75: 103-140, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27770982

RESUMO

Cuvier's beaked whale (Ziphius cavirostris G. Cuvier, 1823) is the only beaked whale species commonly found in the Mediterranean Sea. Until recently, species presence in this area was only inferred from stranding events. Dedicated cetacean surveys have increased our knowledge of the distribution of Cuvier's beaked whales, even though many areas still remain unexplored. Here, we present an updated analysis of available sighting and stranding data, focusing on the atypical mass strandings that have occurred in the Mediterranean Sea since 1963. We describe in detail the five more recent events (2006-14), highlighting their relationship with naval exercises that used mid-frequency active sonar. The distribution of the species is apparently characterized by areas of high density where animals seem to be relatively abundant, including the Alborán Sea, Ligurian Sea, Central Tyrrhenian Sea, southern Adriatic Sea and the Hellenic Trench, but other such areas may exist where little or no survey work has been conducted. Population size has been estimated for the Alborán and Ligurian seas. Habitat modelling studies for those areas, confirmed the species preference for the continental slope and its particular association with submarine canyons, as has also been found to be the case in other areas of the world. The application of results from habitat modelling to areas different from their calibration sites is proposed as a management tool for minimizing the potential impacts of human activities at sea. Military sonar is known worldwide as a threat for this species and is suggested to be a major threat for Cuvier's beaked whale in the Mediterranean Sea.


Assuntos
Conservação dos Recursos Naturais , Baleias/fisiologia , Distribuição Animal , Animais , Mar Mediterrâneo , Dinâmica Populacional
7.
Adv Mar Biol ; 75: 205-232, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27770985

RESUMO

This paper provides a summary of 25 years of research on Risso's dolphins (Grampus griseus) in the western Ligurian Sea. Seasonal variations in abundance, distribution and habitat use were observed. Photographic mark-recapture methods provided a population size estimate for the period from 1998 to 2012, of about 100 individuals (95% CI of 60-220 individuals). The same methods detected a decline in population size from an average of about 120-150 from 2000 to 2005, to an average of 70-100 during 2010 to 2014. Species occurrence appeared to be significantly decreasing in coastal and continental slope areas, while it seemed to be stable in the most pelagic area. In addition, a dramatic change was observed in the local primary production, which was analysed based on time series of sea surface temperature and chlorophyll data from 1990 to 2014. Based on fisheries landings, there may have been a general decrease in fishery productivity, both in the western Ligurian Sea and in adjacent regions. Environmental variability, depletion of resources by fisheries and possibly interspecies competition may all have contributed to cause changes in Risso's dolphin habitat use and occurrence in the western Ligurian Sea.


Assuntos
Golfinhos/fisiologia , Ecossistema , Dinâmica Populacional , Animais , Mar Mediterrâneo , Fatores de Tempo
8.
Rev Sci Instrum ; 95(9)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39230362

RESUMO

We describe the design of a Thomson scattering (TS) diagnostic to be used on the SMall Aspect Ratio Tokamak (SMART). SMART is a spherical tokamak being commissioned in Spain that aims to explore positive triangularity and negative triangularity plasma scenarios at a low aspect ratio. The SMART TS diagnostic is designed to operate at high spatial resolution, 6 mm scattering length in the low-field side and 9 mm in the high-field side regions, and a wide dynamic range, electron temperature from 1 eV to 1 keV and density from 5×1018m-3 to 1×1020m-3, to resolve large gradients formed at the plasma edge and in the scrape-off layer (SOL) under different triangularities and low aspect ratios. A 2 J @1064 nm laser will be used that is capable of operating in the burst mode at 1, 2, and 4 kHz to investigate fast phenomena and at 30 Hz to study 1 s (or more) long discharges. The scattered light will be collected over an angular range of 60° - 120° from 28 spatial points in the midplane covering the entire plasma width and the outer midplane SOL. Each scattering signal will be spectrally resolved on five wavelength channels of a polychromator to obtain the electron temperature measurement. We will also present a method to monitor in situ laser alignment in the core during calibrations and plasma operations.

9.
Phys Rev Lett ; 110(26): 265008, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23848889

RESUMO

The application of static magnetic field perturbations to a tokamak plasma is observed to alter the dynamics of high-frequency bursting Alfvén modes that are driven unstable by energetic ions. In response to perturbations with an amplitude of δB/B∼0.01 at the plasma boundary, the mode amplitude is reduced, the bursting frequency is increased, and the frequency chirp is smaller. For modes of weaker bursting character, the magnetic perturbation induces a temporary transition to a saturated continuous mode. Calculations of the perturbed distribution function indicate that the 3D perturbation affects the orbits of fast ions that resonate with the bursting modes. The experimental evidence represents an important demonstration of the possibility of controlling fast-ion instabilities through "phase-space engineering" of the fast-ion distribution function, by means of externally applied perturbation fields.

10.
Rev Sci Instrum ; 93(9): 093527, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182470

RESUMO

Capacitive plasma pickup is a well-known and difficult problem for plasma-facing edge diagnostics. This problem must be addressed to ensure an accurate and robust interpretation of the real signal measurements vs noise. The Faraday cup fast ion loss detector array of the Joint European Torus (JET) is particularly prone to this issue and can be used as a testbed to prototype solutions. The issue of separation and distinction between warranted fast ion signal and electromagnetic plasma noise has traditionally been solved with hardware modifications, but a more versatile post-processing approach is of great interest. This work presents post-processing techniques to characterize the signal noise. While hardware changes and advancements may be limited, the combination with post-processing procedures allows for more rapid and robust analysis of measurements. The characterization of plasma pickup noise is examined for alpha losses in a discharge from JET's tritium campaign. In addition to highlighting the post-processing methodology, the spatial sensitivity of the detector array is also examined, which presents significant advantages for the physical interpretation of fast ion losses.

11.
Phys Med Biol ; 66(10)2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33831856

RESUMO

Brachytherapy has an excellent clinical outcome for different treatment sites. However,in vivotreatment verification is not performed in the majority of hospitals due to the lack of proper monitoring systems. This study investigates the use of an imaging panel (IP) and the photons emitted by a high dose rate (HDR)192Ir source to track source motion and obtain some information related to the patient anatomy. The feasibility of this approach was studied by monitoring the treatment delivery to a 3D printed phantom that mimicks a prostate patient. A 3D printed phantom was designed with a template for needle insertion, a cavity ('rectum') to insert an ultrasound probe, and lateral cavities used to place tissue-equivalent materials. CT images were acquired to create HDR192Ir treatment plans with a range of dwell times, interdwell distances and needle arrangements. Treatment delivery was verified with an IP placed at several positions around the phantom using radiopaque markers on the outer surface to register acquired IP images with the planning CT. All dwell positions were identified using acquisition times ≤0.11 s (frame rates ≥ 9 fps). Interdwell distances and dwell positions (in relation to the IP) were verified with accuracy better than 0.1 cm. Radiopaque markers were visible in the acquired images and could be used for registration with CT images. Uncertainties for image registration (IP and planning CT) between 0.1 and 0.4 cm. The IP is sensitive to tissue-mimicking insert composition and showed phantom boundaries that could be used to improve treatment verification. The IP provided sufficient time and spatial resolution for real-time source tracking and allows for the registration of the planning CT and IP images. The results obtained in this study indicate that several treatment errors could be detected including swapped catheters, incorrect dwell times and dwell positions.


Assuntos
Braquiterapia , Raios gama , Humanos , Masculino , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X
12.
Rev Sci Instrum ; 91(9): 093502, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33003824

RESUMO

Upgrades to electronic hardware and detector design have been made to the JET thin-foil Faraday cup fast ion loss detector [Darrow et al., Rev. Sci. Instrum. 75, 3566 (2004)] in anticipation of the upcoming deuterium-tritium (DT) campaign. An improved foil stack design has been implemented, which greatly reduces the number of foil-to-foil shorts, and triaxial cabling has mitigated ambient noise pickup. Initial tests of 200 kHz digitizers, as opposed to the original 5 kHz digitizers, have provided enhanced analysis techniques and direct coherence measurements of fast ion losses with magnetohydrodynamic activity. We present recent loss measurements in JET deuterium plasmas correlated with kink modes, fishbone modes, edge-localized modes, and sawteeth. Sources of systematic noise are discussed with emphasis on capacitive plasma pickup. Overall, the system upgrades have established a diagnostic capable of recording alpha particle losses due to a wide variety of resonant fast ion transport mechanisms to be used in future DT-experiments and modeling efforts.

13.
Bone Marrow Transplant ; 41(1): 55-62, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17934532

RESUMO

To assess the kinetics of lymphocyte subset recovery, 758 allografted patients were monitored by surface markers (CD3, CD4, CD8, CD56), with a 5-year follow-up. The donor was a matched sibling donor (MSD) (n=502) or an alternative donor (family mismatched or unrelated, AD) (n=256). The stem cell source was bone marrow for all patients. CD4+ cell recovery was influenced -- in univariate analysis -- by three factors: donor type, patient age and GvHD. This was not the case for CD8+ and CD56+ cells. The median CD4+ cell count on day +35 after HSCT was 86/mul. Patients achieving this CD4+ cell count had significantly lower transplant-related mortality (TRM) compared to patients who did not achieve this CD4+ cell count (20 vs 39%, P=0.00001), due to a lower risk of lethal infections (24 vs 47%, P=0.0003). In multivariate analysis MSD (RR 3.45, P=0.0001) and recipient age less than 16 years (RR 3.23, P=0.003) were significantly associated with a better CD4+ cell recovery. CD4+ counts on day +35 was predicted TRM (RR=1.97, P=0.0017) together with acute GvHD grade II-IV (RR 1.59, P=0.0097). No difference of TRM was observed for CD8+ and CD56+ cell counts.


Assuntos
Contagem de Linfócito CD4 , Transplante de Células-Tronco Hematopoéticas , Adolescente , Adulto , Idoso , Causas de Morte , Criança , Pré-Escolar , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Transplante Homólogo
14.
J Endocrinol Invest ; 31(12): 1063-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19246971

RESUMO

BACKGROUND: Post-partum thyroiditis (PPT) is an autoimmune disorder occurring within the first year following delivery. A variable prevalence has been reported in different surveys. We prospectively evaluated PPT prevalence and outcome in a cohort of pregnant women living in a well-defined geographic area. AIM: A subset from a group of healthy women consecutively evaluated for thyroid function and thyroid autoimmunity during pregnancy, referring to the same obstetric unit, were followed up at 4-6 months and 1 yr after delivery. MATERIALS/SUBJECTS AND METHODS: Follow-up for PPT was performed in 258 pregnant women. Control data were obtained in a comparable group of healthy non-pregnant women. Free T3 (fT3), free T4 (fT4), TSH thyroglobulin/thyroid peroxidase autoantibodies (TgAb/TPOAb), and urinary iodine excretion were measured. RESULTS: Autoantibody positivity was observed in 9.3% of pregnant, similar to control women. Forty-three out of 59 autoantibody-positive women were followed up; 23 showed PPT at the first control, 18 had hypothyroidism at 1 yr (5 had not shown PPT at the first control). Among 215 out of 584 autoantibody-negative women followed up, 27 developed PPT (15 of them without thyroid autoantibodies); 16 developed thyroid autoantibodies without PPT. After 1 yr, 9 women had hypothyroidism: only 1 of them was autoantibody-negative at the former control. Urinary iodine was increased in several pregnant women. CONCLUSIONS: An overall PPT prevalence of about 18% may be estimated. PPT was also observed in autoantibody- negative women. Differences with other surveys may be related to both study protocol and characteristics of the population studied.


Assuntos
Tireoidite Pós-Parto/epidemiologia , Adulto , Algoritmos , Autoanticorpos/sangue , Feminino , Seguimentos , Humanos , Imunoglobulinas Estimuladoras da Glândula Tireoide/sangue , Iodeto Peroxidase/imunologia , Iodo/urina , Itália/epidemiologia , Tireoidite Pós-Parto/sangue , Gravidez , Terceiro Trimestre da Gravidez/sangue , Terceiro Trimestre da Gravidez/urina , Prevalência , Tireoglobulina/imunologia , Adulto Jovem
15.
Rev Sci Instrum ; 89(6): 063507, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29960573

RESUMO

Analysis of fast-ion D-alpha (FIDA) data on National Spherical Torus Experiment-Upgrade (NSTX-U) shows that the cold Dα line contaminates the FIDA baseline. The scattered light is comparable to the FIDA emission. A scattering correction is required to extract the FIDA signal. Two methods that relate the scattered light contamination to the intensity of the cold Dα line are employed. One method uses laboratory measurements with a calibration lamp; the other method uses data acquired during plasma operation and singular value decomposition analysis. After correction, both the FIDA spectra and spatial profile are in better agreement with theoretical predictions.

16.
Bone Marrow Transplant ; 39(6): 341-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17277788

RESUMO

We assessed the long-term outcome of patients with relapsed acute myeloid (n=86) or acute lymphoid leukemia (n=66), undergoing an allogeneic hemopoietic stem cell transplantation in our unit. The median blast count in the marrow was 30%. Conditioning regimen included total body irradiation (TBI) (10-12 Gy) in 115 patients. The donor was a matched donor (n=132) or a family mismatched donor (n=20). Twenty-two patients (15%) survive disease free, with a median follow-up of 14 years: 18 are off medications. The cumulative incidence of transplant related mortality is 40% and the cumulative incidence of relapse related death (RRD) is 45%. In multivariate analysis of survival, favorable predictors were chronic graft-versus-host disease (GvHD) (P=0.0003), donor other than family mismatched (P=0.02), donor age less than 34 years (P=0.02) and blast count less than 30% (P=0.07). Patients with all four favorable predictors had a 54% survival. In multivariate analysis of relapse, protective variables were the use of TBI (P=0.005) and cGvHD (P=0.01). This study confirms that a fraction of relapsed leukemias is cured with an allogeneic transplant: selection of patients with a blast count <30%, identification of young, human leukocyte antigen-matched donors and the use of total body radiation may significantly improve the outcome.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide/terapia , Recidiva Local de Neoplasia/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Doença Aguda , Adolescente , Adulto , Exame de Medula Óssea , Criança , Feminino , Seguimentos , Sobrevivência de Enxerto , Doença Enxerto-Hospedeiro , Humanos , Estimativa de Kaplan-Meier , Leucemia Mieloide/complicações , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Prognóstico , Sobreviventes , Transplante Homólogo
17.
Bone Marrow Transplant ; 38(2): 111-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16751783

RESUMO

A bone marrow harvest is filtered either in the operating room, in the laboratory or during infusion to the patient. Filters are usually discarded. Little is known of haemopoietic progenitor cells (HPCs) trapped in the filters. The aim of the study was to evaluate HPC content in the filters and to assess the outcome of transplants with filter-discarded or filter-recovered cells. Haemopoietic progenitors were grown from filters of 19 marrow transplants. We then compared the outcome of 39 filter-recovered transplants from HLA-identical siblings (years 2001-2004) with a matched cohort of 43 filter-discarded marrow grafts (years 1997-2000). Filters contained on average 21% long-term culture-initiating cells (LTC-IC) and 15% fibroblasts colony-forming units (CFU-F) of the total progenitor cell content. Filter-discarded transplants had significantly more grade II-IV graft-versus-host disease (GvHD) (42 vs 15%, P=0.008) as compared to filter-recovered transplants, and more transplant-related mortality (TRM) (20 vs 3%, P=0.04). The actuarial survival at 5 years is 69 vs 87%, respectively (P=0.15). This study suggests that a significant proportion of LTC-IC is lost in the filters together with CFU-F. Recovery and add back of progenitors trapped in the filters may reduce GvHD and TRM.


Assuntos
Transplante de Medula Óssea/métodos , Filtração/métodos , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/citologia , Adolescente , Adulto , Transplante de Medula Óssea/efeitos adversos , Células Cultivadas , Feminino , Citometria de Fluxo/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
18.
Technol Cancer Res Treat ; 15(6): NP79-NP87, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26655145

RESUMO

PURPOSE: It is desirable that dosimetric deviations during radiation treatments are detected. Integrated transit planar dosimetry is commonly used to evaluate external beam treatments such as volumetric-modulated arc therapy. This work focuses on patient geometry changes which result in differences between the planned and the delivered radiation dose. Integrated transit planar dosimetry will average out some deviations. Novel time-resolved transit planar dosimetry compares the delivered dose of volumetric-modulated arc therapy to the planned dose at various time points. Four patient cases are shown where time-resolved transit planar dosimetry detects patient geometry changes during treatment. METHODS: A control point to control point comparison between the planned dose and the treatment dose of volumetric-modulated arc therapy beams is calculated using the planning computed tomography and the kV cone-beam computed tomography of the day and evaluated with a time-resolved γ function. Results were computed for 4 patients treated with volumetric-modulated arc therapy, each showing an anatomical change: pleural effusion, rectal gas pockets, and tumor regression. RESULTS: In all cases, the geometrical change was detected by time-resolved transit planar dosimetry, whereas integrated transit planar dosimetry showed minor or no indication of the dose discrepancy. Both tumor regression cases were detected earlier in the treatment with time-resolved planar dosimetry in comparison to integrated transit planar dosimetry. The pleural effusion and the gas pocket were detected exclusively with time-resolved transit planar dosimetry. CONCLUSIONS: Clinical cases were presented in this proof-of-principle study in which integrated transit planar dosimetry did not detect dosimetrically relevant deviations to the same extent time-resolved transit planar dosimetry was able to. Time-resolved transit planar dosimetry also provides results that can be presented as a function of arc delivery angle allowing easier interpretation compared to integrated transit planar dosimetry.


Assuntos
Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Humanos , Neoplasias/radioterapia , Derrame Pleural/radioterapia , Dosagem Radioterapêutica
19.
J Clin Oncol ; 15(4): 1575-82, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9193355

RESUMO

PURPOSE: Mobilization of Philadelphia (Ph) chromosome-negative progenitors is now possible in many Ph1-positive chronic myelogenous leukemia (CML) patients who had received interferon alfa (IFN-alpha) with no cytogenetic response. In this pilot study, we used this approach in patients without prior IFN-alpha therapy to determine if the number and quality of mobilized progenitors would be increased and to evaluate the potential effect of these cells as autografts. PATIENTS AND METHODS: Twenty-two untreated patients were mobilized within 12 months of diagnosis. The treatment regimen consisted of the mini-ICE protocol. Beginning on day +8, granulocyte colony-stimulating factor (G-CSF) was used in all patients. Leukophoresis was performed as the patients were recovering from aplasia, when WBC count exceeded 0.8 x 10(9)/L. RESULTS: In 14 patients, (63%) the leukophoresis product was entirely Ph1-negative and in four patients the Ph1-positive cell rate was < or = 7%. Significant numbers of long-term culture-initiating cells (LTC-IC) and CD34+ Thy1+Lin- cells were found in most of the Ph1-negative collections that were tested. Twelve patients underwent autografting with their mobilized peripheral-blood progenitor cells (PBPC) (Ph1-negative collections, 10 patients; major cytogenetic response, two patients). All patients engrafted and are alive; six have Ph1-negative marrow 7 to 15 months after autografting. Posttransplant treatment was IFN-alpha combined with interleukin (IL)-2 because of the recent demonstration of synergistic activity in augmenting cytolytic activity. CONCLUSION: Intensive chemotherapy given in early chronic phase of CML is well tolerated and results in high numbers of circulating Ph1-negative precursor cells.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mielogênica Crônica BCR-ABL Positiva/cirurgia , Adulto , Antineoplásicos/uso terapêutico , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Cromossomo Filadélfia , Projetos Piloto , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento
20.
Leukemia ; 6 Suppl 4: 120-3, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1359202

RESUMO

Forty patients with Ph-positive blastic phase (BP) (28 patients) or chronic phase (CP)-CML (3 patients) and relapsed adult acute lymphoblastic leukemia (ALL) (9 patients) with cytogenetical translocations [t(8;14):2 patients; t(4;8):2 patients; t(4;11):3 patients; t(9;22):2 patients], received an intensive conventional chemotherapy. During early recovery from marrow aplasia, when WBC reached 0.3-1.5 x 10--9/L, peripheral blood stem cells (BSC) were collected by 4-8 leukapheresis consecutively. BSC collected from the 2/3 patients with CP-CML resulted Ph-negative and PCR negative. In 8 out of 26 BP-CML patients, BSC resulted Ph-negative and in two cases PCR negative. Of the nine ALL patients, 6 patients lost the cytogenetic translocations, one patient died during aplasia, two patients did not have cytogenetic modifications and died in few weeks of leukemia and one patient out of six responding patients relapsed before transplant. After complete recovery, 15 patients (BP-CML:8 patients; CP-CML:2 patients; ALL:5 patients) were subsequently given high-dose therapy (VP-16 +/- Cy+TBI in single dose) followed by reinfusion of "normal" BSC. Both the patients in CP-CML and 5/5 patients with ALL maintain clinical and cytogenetic remission; all the patients transplanted in BP-CML relapsed 5-18 months post-transplant. It is concluded that intensive conventional chemotherapy employed in CML and ALL can lead to a precocious overshoot of cytogenetically normal BSC.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Células-Tronco Hematopoéticas/ultraestrutura , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Translocação Genética
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