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1.
Gene Ther ; 23(3): 247-55, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26583804

RESUMEN

Administration of therapeutic gene sequences coding for chondrogenic and chondroreparative factors in bone marrow aspirates using the clinically adapted recombinant adeno-associated virus (rAAV) vector may provide convenient, single-step approaches to improve cartilage repair. Here, we tested the ability of distinct rAAV constructs coding for the potent SOX9, transforming growth factor beta (TGF-ß) and insulin-like growth factor I (IGF-I) candidate factors to modify marrow aspirates from minipigs to offer a preclinical large animal model system adapted for a translational evaluation of cartilage repair upon transplantation in sites of injury. Our results demonstrate that high, prolonged rAAV gene transfer efficiencies were achieved in the aspirates (up to 100% for at least 21 days) allowing to produce elevated amounts of the transcription factor SOX9 that led to increased levels of matrix synthesis and chondrogenic differentiation and of the growth factors TGF-ß and IGF-I that both increased cell proliferation, matrix synthesis and chondrogenic differentiation (although to a lower level than SOX9) compared with control (lacZ) condition. Remarkably, application of the candidate SOX9 vector also led to reduced levels of hypertrophic differentiation in the aspirates, possibly by modulating the ß-catenin, Indian hedgehog and PTHrP pathways. The present findings show the benefits of modifying minipig marrow concentrates via rAAV gene transfer as a future means to develop practical strategies to promote cartilage repair in a large animal model.


Asunto(s)
Condrogénesis , Dependovirus/genética , Vectores Genéticos/uso terapéutico , Factor I del Crecimiento Similar a la Insulina/uso terapéutico , Factor de Transcripción SOX9/uso terapéutico , Factor de Crecimiento Transformador beta/uso terapéutico , Animales , Trasplante de Médula Ósea , Cartílago/lesiones , Factor I del Crecimiento Similar a la Insulina/genética , Factor de Transcripción SOX9/genética , Porcinos , Porcinos Enanos , Factor de Crecimiento Transformador beta/genética
2.
Gene Ther ; 22(1): 50-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25338919

RESUMEN

The genetic modification of freshly aspirated bone marrow may provide convenient tools to enhance the regenerative capacities of cartilage defects compared with the complex manipulation of isolated progenitor cells. In the present study, we examined the ability and safety of recombinant adeno-associated virus (rAAV) serotype 2 vectors to deliver various reporter gene sequences in primary human bone marrow aspirates over time without altering the chondrogenic processes in the samples. The results demonstrate that successful rAAV-mediated gene transfer and expression of the lacZ and red fluorescent protein marker genes were achieved in transduced aspirates at very high efficiencies (90-94%) and over extended periods of time (up to 125 days) upon treatment with hirudin, an alternative anticoagulant that does not prevent the adsorption of the rAAV-2 particles at the surface of their targets compared with heparin. Application of rAAV was safe, displaying neither cytotoxic nor detrimental effects on the cellular and proliferative activities or on the chondrogenic processes in the aspirates especially using an optimal dose of 0.5 mg ml(-1) hirudin, and application of the potent SOX9 transcription factor even enhanced these processes while counteracting hypertrophic differentiation. The current findings demonstrate the clinical value of this class of vector to durably and safely modify bone marrow aspirates as a means to further develop convenient therapeutic approaches to improve the healing of cartilage defects.


Asunto(s)
Células de la Médula Ósea/fisiología , Diferenciación Celular , Dependovirus/genética , Anticoagulantes/farmacología , Células Cultivadas , Condrogénesis , Genes Reporteros , Heparina/farmacología , Hirudinas/farmacología , Humanos , Proteínas Luminiscentes/biosíntesis , Proteínas Luminiscentes/genética , Cultivo Primario de Células , Factor de Transcripción SOX9/metabolismo , Transducción Genética , Transgenes , Proteína Fluorescente Roja
3.
Opt Lett ; 39(18): 5325-8, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26466262

RESUMEN

Using balanced detection in both the radio frequency (RF) and the optical domain, we remotely synchronize the repetition rate of a Ti:sapphire oscillator to an Er-doped fiber oscillator through a 360 m length-stabilized dispersion compensated fiber link. The drift between these two optical oscillators is 3.3 fs root mean square (rms) over 24 hours. The 68 MHz Er-doped fiber oscillator is locked to a 476 MHz local RF reference clock, and serves as a master clock to distribute 10 fs-level timing signals through stabilized fiber links. This steady remote two-color optical-to-optical synchronization is an important step toward an integrated femtosecond fiber timing distribution system for free-electron lasers (FELs); it does not require x-ray pulses, and it makes sub-10-fs optical/x-ray pump-probe experiments feasible.

4.
Phys Rev Lett ; 111(18): 184801, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24237525

RESUMEN

Modern, high-brightness electron beams such as those from plasma wakefield accelerators and free-electron laser linacs continue the drive to ever-shorter bunch durations. In low-charge operation (~20 pC), bunches shorter than 10 fs are reported at the Linac Coherent Light Source (LCLS). Though suffering from a loss of phase information, spectral diagnostics remain appealing as compact, low-cost bunch duration monitors suitable for deployment in beam dynamics studies and operations instrumentation. Progress in middle-infrared (MIR) imaging has led to the development of a single-shot, MIR prism spectrometer to characterize the corresponding LCLS coherent beam radiation power spectrum for few-femtosecond scale bunch length monitoring. In this Letter, we report on the spectrometer installation as well as the temporal reconstruction of 3 to 60 fs-long LCLS electron bunch profiles using single-shot coherent transition radiation spectra.

5.
Pharmacopsychiatry ; 46(5): 175-80, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23737243

RESUMEN

INTRODUCTION: Aripiprazole, an atypical antipsychotic drug with mixed antagonism and agonism on dopamine D2 and serotonin receptors, is a substrate of the efflux transporter P-glycoprotein (P-gp). Here we tested the pharmacodynamic consequences of these properties in a P-gp deficient mouse model by studying the effects of aripiprazole and of ziprasidone on motor coordination. METHODS: The motor behaviour of wild-type (WT) and P-gp deficient [abcb1ab(-/-)] mice was investigated on a RotaRod. Mice received acute injections of either aripirazole or ziprasidone. For comparison, the dopamine receptor antagonist haloperidol and serotonin receptor ligands buspirone and ketanserin were also applied. RESULTS: Pharmacokinetic analyses revealed P-gp activity for aripiprazole and ziprasidone. This was indicated by 3.1- and 1.9-fold higher ratios of brain to plasma concentrations of drugs in knock-out to WT animals. Acute doses of ariprazole or ziprasidone impaired motor behaviour on the RotaRod. Effects were similar after injection of haloperidol, whereas the serotonin receptor ligands buspirone and ketanserin enhanced RotaRod performance. Genotype dependent differences of motor performance were found for aripiprazole but not for ziprasidone. DISCUSSION: Evidence was given that P-gp substrate properties have pharmacodynamic consequences for aripiprazole but not for ziprasidone and thus affect dopamine receptor related motor behaviour.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Antipsicóticos/farmacología , Actividad Motora/efectos de los fármacos , Piperazinas/farmacología , Quinolonas/farmacología , Prueba de Desempeño de Rotación con Aceleración Constante , Tiazoles/farmacología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/deficiencia , Animales , Antipsicóticos/farmacocinética , Aripiprazol , Buspirona/farmacología , Haloperidol/farmacología , Ketanserina/farmacología , Masculino , Ratones , Ratones Noqueados , Piperazinas/farmacocinética , Quinolonas/farmacocinética , Antagonistas de la Serotonina/farmacología , Agonistas de Receptores de Serotonina/farmacología , Tiazoles/farmacocinética
6.
Phys Rev Lett ; 109(25): 254802, 2012 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-23368472

RESUMEN

We report the first measurements of x-ray single-pulse duration and two-pulse separation at the Linac Coherent Light Source using a cross-correlation technique involving x rays and electrons. An emittance-spoiling foil is adopted as a very simple and effective method to control the output x-ray pulse. A minimum pulse duration of about 3 fs full width at half maximum has been measured together with a controllable pulse separation (delay) between two pulses. This technique provides critical temporal diagnostics for x-ray experiments such as x-ray pump-probe studies.

7.
Opt Express ; 18(17): 17620-30, 2010 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-20721148

RESUMEN

The first time-resolved x-ray/optical pump-probe experiments at the SLAC Linac Coherent Light Source (LCLS) used a combination of feedback methods and post-analysis binning techniques to synchronize an ultrafast optical laser to the linac-based x-ray laser. Transient molecular nitrogen alignment revival features were resolved in time-dependent x-ray-induced fragmentation spectra. These alignment features were used to find the temporal overlap of the pump and probe pulses. The strong-field dissociation of x-ray generated quasi-bound molecular dications was used to establish the residual timing jitter. This analysis shows that the relative arrival time of the Ti:Sapphire laser and the x-ray pulses had a distribution with a standard deviation of approximately 120 fs. The largest contribution to the jitter noise spectrum was the locking of the laser oscillator to the reference RF of the accelerator, which suggests that simple technical improvements could reduce the jitter to better than 50 fs.


Asunto(s)
Electrones , Rayos Láser , Sincrotrones , Diseño de Equipo , Fibras Ópticas , Factores de Tiempo , Rayos X
8.
J Clin Oncol ; 10(9): 1452-9, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1517788

RESUMEN

PURPOSE: To combine the benefits of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) on neutrophil recovery and recombinant human interleukin-3 (rhIL-3) on platelet recovery, we applied standard-dose chemotherapy with the combined administration of IL-3 and GM-CSF to investigate their efficacy and toxicity. PATIENTS AND METHODS: Thirty-six patients with advanced malignancies were treated with etoposide (VP16) 500 mg/m2, ifosfamide 4 g/m2, and cisplatin 50 mg/m2 (VIP), followed by the sequential administration of IL-3 (days 1 to 5 subcutaneously [SC]) and GM-CSF (day 6 to 15 SC). Control patients received GM-CSF alone or were treated without hematopoietic growth factors. RESULTS: Subcutaneous IL-3 and GM-CSF treatment was well tolerated; low-grade fever (World Health Organization grade 1 to 2) was the only consistent clinical symptom. Neutrophil recovery documented that the duration of neutropenia less than 0.1 x 10(9)/L or less than 0.5 x 10(9)/L was identical in GM-CSF as well as IL-3 and GM-CSF-treated patients, but was shortened significantly when compared with patients who were treated without cytokines. Overall platelet recovery was not different significantly in the three treatment groups. The biologic activity of IL-3 in this cytokine combination was reflected in a variety of effects, which included an increase in basophil and eosinophil counts and the induction of circulating hematopoietic progenitor cells. CONCLUSION: We conclude that after conventional-dose VIP chemotherapy, a shortened treatment course of IL-3 (5 days) sequentially followed by GM-CSF (10 days) combines the benefits of prolonged single GM-CSF treatment on WBC count recovery in all patients and an accelerated platelet recovery only in some intensively pretreated patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/administración & dosificación , Interleucina-3/administración & dosificación , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Cisplatino/administración & dosificación , Esquema de Medicación , Evaluación de Medicamentos , Etopósido/administración & dosificación , Estudios de Factibilidad , Femenino , Hematopoyesis/efectos de los fármacos , Humanos , Ifosfamida/administración & dosificación , Masculino , Persona de Mediana Edad , Neutrófilos/efectos de los fármacos , Proteínas Recombinantes/administración & dosificación
9.
J Clin Oncol ; 9(12): 2120-7, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1960553

RESUMEN

The biologic in vivo effects of recombinant human interleukin-3 (rhIL-3) were assessed in a phase I clinical study of 30 patients with advanced malignancy. On day 1 rhIL-3 was administered by a single intravenous (IV) bolus injection, followed by subcutaneous (SC) injections once daily from day 2 to 15; at least three patients were treated at each dose level (60, 125, 250, and 500 micrograms/m2). A transient decrease of eosinophil and monocyte counts was observed immediately after IV injection of rhIL-3, whereas the neutrophil count remained unaffected. Total WBC counts and neutrophil counts increased dose dependently up to threefold, whereas a 10-fold to 50-fold rise was observed in levels of circulating eosinophils and basophils. Platelet counts increased up to twofold. Patients developed moderate increases of serum levels of soluble interleukin-2 receptors, beta 2-microglobin, and immunoglobulin M (IgM), and of the acute phase reactants, C-reactive protein (CRP), fibrinogen, and haptoglobin. An increase in interleukin-6 (IL-6) serum levels was detected in patients treated by IV bolus rhIL-3. The serum half-life of IV injected rhIL-3 was 20 +/- 3 minutes; after SC administration, 210 +/- 15 minutes. Administration of rhIL-3 was generally well tolerated, with mild fever, headache, and local reactions at the injection site being the most frequent side effects. The primary course of the underlying malignant diseases was not significantly altered by administration of rhIL-3. The results indicate that rhIL-3 acts in vivo as a multilineage hematopoietic growth factor and a weak inflammatory mediator that may be used successfully to improve states of hematopoietic failure.


Asunto(s)
Interleucina-3/farmacología , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Evaluación de Medicamentos , Ensayo de Inmunoadsorción Enzimática , Eosinófilos/efectos de los fármacos , Femenino , Humanos , Interleucina-3/sangre , Interleucina-3/uso terapéutico , Recuento de Leucocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Neoplasias/sangre , Recuento de Plaquetas/efectos de los fármacos , Proteínas Recombinantes/farmacología
10.
J Clin Oncol ; 16(2): 642-50, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9469353

RESUMEN

PURPOSE: To assess whether granulocyte-macrophage colony-stimulating factor (GM-CSF) reduces the toxicity of chemotherapy and alters delivered dose-intensity. To assess the feasibility of dose-intensification of chemotherapy in small-cell lung cancer (SCLC) and determine whether it has an impact on outcome. MATERIALS AND METHODS: Patients with good- or intermediate-prognosis SCLC entered a prospective multicenter study that involved a 2 x 2 factorial design with randomization to six cycles of chemotherapy with ifosfamide 5 g/m2, carboplatin 300 mg/m2, etoposide 120 mg/m2 intravenously (I.V.) on days 1 and 2 and 240 mg/m2 orally on day 3, and vincristine 0.5 mg/m2 I.V. on day 15 (V-ICE) every 3 weeks (intensified arm) or every 4 weeks (standard arm). A second double-blind randomization to subcutaneous GM-CSF (250 microg/m2/d) or placebo for 14 days between chemotherapy cycles was made. RESULTS: Three hundred patients were entered. Myelosuppression was the main toxicity, with no significant difference in the incidence or grade between treatment groups. The incidence of febrile neutropenia and bacteriologically confirmed sepsis was unaffected by chemotherapy schedule or use of GM-CSF. Twenty-six percent greater dose-intensity was delivered in the intensified arm, with a trend for greater dose-intensity for those who received GM-CSF. Eighty-three percent of patients achieved a response (51% complete response [CR] rate), with no significant difference in response rates between treatment groups. Survival was significantly increased in the intensified compared with the standard arm (P = .0014); median survival rates were 443 versus 351 days and 2-year survival rates were 33% versus 18%, respectively. CONCLUSION: GM-CSF does not reduce the incidence of complications from myelosuppression of aggressive chemotherapy. Dose intensification of V-ICE to a 3-week schedule in SCLC is not associated with increased toxicity, but appears to improve survival significantly. Future studies should aim to deliver chemotherapy in maximal-tolerated dose-intensities.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Pequeñas/tratamiento farmacológico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/administración & dosificación , Neoplasias Pulmonares/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carboplatino/administración & dosificación , Carboplatino/efectos adversos , Carcinoma de Células Pequeñas/mortalidad , Método Doble Ciego , Etopósido/administración & dosificación , Etopósido/efectos adversos , Femenino , Humanos , Ifosfamida/administración & dosificación , Ifosfamida/efectos adversos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tasa de Supervivencia , Vincristina/administración & dosificación , Vincristina/efectos adversos
11.
J Clin Oncol ; 18(14): 2676-84, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10894866

RESUMEN

PURPOSE: This randomized multicenter study was designed to compare the activity of a high-dose doxorubicin-containing chemotherapy regimen with a conventional standard-dose regimen in adult patients with advanced soft tissue sarcomas (ASTS). PATIENTS AND METHODS: Between 1992 and 1995, 314 patients were randomized to receive a standard-dose regimen (arm A), containing doxorubicin (50 mg/m(2) on day 1) and ifosfamide (5 g/m(2) on day 1), or an intensified regimen (arm B), combining doxorubicin (75 mg/m(2) on day 1), the same ifosfamide dose, and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; sargramostim, 250 microgram/m(2) on days 3 to 16); all courses were repeated every 3 weeks. RESULTS: The median age of the 294 eligible patients was 50 years. They received a median of five chemotherapy cycles. The median dose and relative doxorubicin dose-intensity achieved were 245 mg and 97% in arm A and 360 mg and 99% in arm B, respectively. Thirty-eight percent and 23% of patients presented with leiomyosarcomas and liver metastases, respectively. Objective responses were observed in 31 (21%) of 147 assessable patients in arm A and in 31 (23.3%) of 133 in arm B (P =.65). No change was observed in 41.6% and 46.2% of patients in arm A and B, respectively. Progression-free survival (PFS) was significantly longer in the intensive arm (P =.03). The median duration of the time to progression was 19 weeks in the conventional arm and 29 weeks in the intensified arm. There was no difference in overall survival (P =.98) between the two therapeutic arms. Toxicities were manageable in both arms. A grade 3/4 neutropenia and infection occurred in 92% and 4.6% of patients in arm A, respectively, and in 90% and 16.6% in arm B, respectively. Grade 3/4 thrombocytopenia was more frequent in arm B. CONCLUSION: The use of rhGM-CSF allowed safe escalation of chemotherapy doses. Despite a 50% increase of the doxorubicin dose-intensity, the high-dose regimen failed to demonstrate any impact on survival in patients with ASTS. The low complete response rate, the high incidence of leiomyosarcomas, and liver metastases may in part explain these results. However, the lengthening of the PFS in the intensive arm, because of the quality of stable disease and inappropriate tumor evaluation policies that potentially lead to an underestimation of antitumor activity, does not definitively refute the use of a high-dose chemotherapy regimen in selected patients with ASTS.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Sarcoma/tratamiento farmacológico , Adulto , Anciano , Doxorrubicina/administración & dosificación , Esquema de Medicación , Femenino , Humanos , Ifosfamida/administración & dosificación , Leiomiosarcoma/tratamiento farmacológico , Leiomiosarcoma/secundario , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Proteínas Recombinantes , Sarcoma/secundario , Análisis de Supervivencia
12.
Leukemia ; 7(5): 696-701, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8483321

RESUMEN

In a phase II study, involving nine patients with refractory anemia or refractory anemia with ring sideroblasts, the effects of treatment with recombinant human interleukin-3 (IL-3) on hematopoietic function were assessed. Doses of IL-3 ranging from 60 micrograms/m2 during weeks 1-6 to 125 micrograms/m2 during weeks 7-12 were administered as subcutaneous bolus injections three times per week for 12 weeks. Platelet counts increased in six patients. Platelet increase correlated with stable or decreased serum tumour necrosis factor alpha (TNF-alpha) levels, while an increase of TNF-alpha levels during IL-3 therapy occurred in patients with no change or a decrease of platelet counts. Leukocyte counts increased in two patients and reticulocytes in three, without an effect on hemoglobin levels. Morphological analysis of the bone marrow revealed an expansion of the myeloid compartment in seven of eight evaluable patients, mainly due to stimulation of the precursor cells. No improvement of the in vitro growth of hematopoietic progenitor cells was observed. Sequential cytogenetic analyses indicate that IL-3 treatment does not act preferentially on either the cytogenetically abnormal or the normal clones. These results suggest that long-term treatment with low-dose IL-3 stimulates megakaryopoiesis with increase of platelet counts, but that additional later-acting cytokines probably will be required to augment neutrophil and erythrocyte counts.


Asunto(s)
Interleucina-3/administración & dosificación , Síndromes Mielodisplásicos/terapia , Anciano , Recuento de Células Sanguíneas , Células de la Médula Ósea , Citogenética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes , Factores de Tiempo
13.
Leukemia ; 9(1): 3-9, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7845026

RESUMEN

We investigated whether GM-CSF given concomitantly with chemotherapy (CT) and thereafter, improves the outcome of adults with de novo AML by increasing the efficacy of CT and reducing infections. CT included Ara-C, daunorubicin and etoposide (DAV) for induction and early consolidation therapy and one cycle with high-dose (patients aged < or = 50 years) or intermediate dose Ara-C (patients aged > 50 years)/daunorubicin for late consolidation therapy. Eight patients were randomized after DAVI to receive either GM-CSF (E. coli, 250 micrograms/m2/day, s.c.) or placebo starting 48 h prior to DAVII and the subsequent courses and given throughout CT until the absolute neutrophil count had recovered to > 500/microliters. The CR rate was 81% in the GM-CSF and 79% in the placebo group (p = 0.57; Fisher's exact test). The probability of relapse-free survival at 41 months after a median follow-up of 35 months was 42% in the GM-CSF and 41% in the placebo group (p = 0.89; log rank test). GM-CSF did not shorten the period of neutropenia < or = 500/microliters, while it prolonged the duration of thrombocytopenia < or = 25,000/microliters. The incidence and severity of infections as well as the non-hematological toxicity were similar in both groups. In summary, in this randomized trial GM-CSF as an adjunct to AML therapy was feasible. For the present GM-CSF does not have a significant effect on treatment outcome.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Leucemia Mieloide Aguda/terapia , Adolescente , Adulto , Anciano , Método Doble Ciego , Femenino , Estudios de Seguimiento , Factor Estimulante de Colonias de Granulocitos y Macrófagos/efectos adversos , Humanos , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Tasa de Supervivencia
14.
Nat Commun ; 6: 8889, 2015 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-26567699

RESUMEN

Spin waves, the collective excitations of spins, can emerge as nonlinear solitons at the nanoscale when excited by an electrical current from a nanocontact. These solitons are expected to have essentially cylindrical symmetry (that is, s-like), but no direct experimental observation exists to confirm this picture. Using a high-sensitivity time-resolved magnetic X-ray microscopy with 50 ps temporal resolution and 35 nm spatial resolution, we are able to create a real-space spin-wave movie and observe the emergence of a localized soliton with a nodal line, that is, with p-like symmetry. Micromagnetic simulations explain the measurements and reveal that the symmetry of the soliton can be controlled by magnetic fields. Our results broaden the understanding of spin-wave dynamics at the nanoscale, with implications for the design of magnetic nanodevices.

15.
Rev Sci Instrum ; 86(7): 073702, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26233391

RESUMEN

Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.

16.
Int J Parasitol ; 29(1): 57-71; discussion 73-5, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10048820

RESUMEN

Acaricides are essential in the short-term but do not offer a permanent solution to tick control. This situation will not change without a change of approach. A vaccine against Boophilus microplus confers partial long-term control but has little immediate effect on tick burdens. The effectiveness of acaricides and vaccination is greatest for breeds of high tick resistance. High host resistance is the key to effective long-term tick control with total resistance the ultimate aim. While improvements to acaricides and vaccines are continuously pursued, improvements to the most important single factor controlling ticks, host resistance, have been neglected. Resistance is as heritable as milk yield or growth and in tropical breeds can be increased to very high levels by selection. Despite this there are no current examples of sustained selection for tick resistance. Temperate breeds have low resistance but because of high production potentials are favoured for crossbreeding with tropical breeds. This perpetuates the need for reliance on acaricides. Selection to increase polygenic resistance of temperate breeds is impractical. However, a quantum increase can be achieved by introgressing major resistance genes. Such a gene occurs in the Belmont Adaptaur and in suitable genetic backgrounds confers 100% resistance. Total resistance is achievable and provides a permanent solution to ticks.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Control de Ácaros y Garrapatas , Infestaciones por Garrapatas/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/parasitología , Inmunidad Innata/genética , Insecticidas , Infestaciones por Garrapatas/inmunología , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/prevención & control , Garrapatas/crecimiento & desarrollo , Garrapatas/inmunología , Vacunas
17.
Int J Parasitol ; 30(3): 253-64, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10719118

RESUMEN

Ever since their accidental introduction, cattle ticks, gastrointestinal nematodes and buffalo flies have been major parasites of cattle in northern Australia. Enormous effort and resources have been directed at chemical control of these parasites but the problem persists in undiminished form. The principal control measure remains the use of breeds that have some degree of parasite resistance. No breed is completely resistant and all are at times adversely affected by parasites. Complete resistance is the ultimate solution but has been generally ignored as a commercial reality. Studies at Rockhampton have demonstrated that completely resistant lines can be developed by genetic means within a commercially acceptable timeframe from even the most parasite-susceptible breeds. Genetic changes in tick and worm resistance over 15 years in response to selection for increased tick resistance in the Belmont Adaptaur (Bos taurus) line are reported. Costs and benefits of achieving increased tick resistance are examined and the applicability of the results to other breeds is discussed. Breed differences in resistance to buffalo flies and their effects on live weight are also reported and the possibility of selecting for increased buffalo fly resistance is explored.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Bovinos/genética , Inmunidad Innata/genética , Enfermedades Parasitarias en Animales/prevención & control , Selección Genética , Animales , Australia , Cruzamiento , Bovinos/inmunología , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/parasitología , Cruzamientos Genéticos , Femenino , Masculino , Enfermedades Parasitarias en Animales/inmunología
18.
Surgery ; 91(5): 597-602, 1982 May.
Artículo en Inglés | MEDLINE | ID: mdl-7071748

RESUMEN

From 1975 through 1979, 29 members of The Cleveland Vascular Society operated on 1049 patients with abdominal aortic aneurysms; of these, 152 ruptured aneurysms. The postoperative mortality rate was 38% (58 of 152). In 27% (41 of 152) of the patients, a diagnosis was made prior to rupture, and the average interval from diagnosis rupture was 16 months. A history of diabetes, hypertension, or a single myocardial infarction (MI) prior to rupture was not associated with an increased mortality rate. Patients with a history of more than one MI prior to rupture had a 75% (six of eight) mortality rate. The average time from onset of symptoms to examination was 2 days 10 hours. When the initial diagnosis was correct, or an intra-abdominal disease was at least suspected, the mortality rate was 35% (47 of 135). When the initial diagnosis was incorrect and a cardiopulmonary or cerebral cause was suspected, the mortality rate was 75% (13 of 17). When the diagnosis was incorrect, the interval from diagnosis to surgery was 2 1/2 days. With only intramural bleeding or a small hematoma in the area of rupture, the mortality rate was 17% (4 of 24); when the hematoma was more extensive, the mortality rate was 43% (55 of 128). This study encompassed a large number of operations performed in a metropolitan area during a relatively short period of time, during which there had been few changes in operative technique or supportive measures. It demonstrated that the most critical factors influencing survival were correct initial diagnosis, the extent of the hematoma, and the history of more than one preoperative MI.


Asunto(s)
Rotura de la Aorta/mortalidad , Anciano , Aorta Abdominal/cirugía , Rotura de la Aorta/diagnóstico , Rotura de la Aorta/cirugía , Presión Sanguínea , Errores Diagnósticos , Femenino , Hematócrito , Humanos , Masculino , Ohio , Complicaciones Posoperatorias/mortalidad , Pronóstico
19.
J Exp Biol ; 199(Pt 3): 529-35, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9318220

RESUMEN

Thoracic temperatures (Tth) of Libellula pulchella dragonflies during activity in the field were compared between age classes and with laboratory measures of optimal thoracic temperature for flight performance (Tth,opt; a trait that varies during adult maturation in this species). Newly emerged adults (tenerals) had mean Tth values during flight (34.5 °C; range 29-40 °C) that did not differ from their mean Tth,opt (34.6 °C; range 28.5-43.8 °C). Mature adults had higher and more precisely regulated thoracic temperatures (mean Tth 41.7 °C; range 37.5-45.2 °C), which were somewhat lower than their mean Tth,opt (43.6 °C; range 38.7-49.9 °C). Among matures, behaviors requiring the highest levels of flight exertion (aerial copulation; mate guarding; escalated territorial contests) caused an elevation of Tth above that of concurrently sampled individuals engaged in routine flight (mean Tth difference 1.3 °C), which raised mean Tth to a level that was not significantly different from Tth,opt (42.5 versus 43.5 °C). Compared with tenerals, matures spent more time flying, made longer-duration flights and showed a more restricted pattern of daily activity. Sympatric Anax junius dragonflies that regulate Tth endothermically had a uniform pattern of activity across the entire day, i.e. occupied a broader ecological niche than that of L. pulchella. These results support the hypotheses that optimal body temperature evolves to match the elevated body temperatures that occur during exercise and that the ecological benefits of an expanded niche are a secondary benefit rather than a primary selective force during the evolution of homeothermy and high body temperatures.

20.
Recent Results Cancer Res ; 121: 162-72, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1857856

RESUMEN

Nine patients with bone marrow failure and prolonged severe cytopenias were treated with recombinant human interleukin-3 (rhIL-3) at doses ranging from 30 micrograms/m2 to 500 micrograms/m2. rhIL-3 was administered in a subcutaneous bolus injection daily for 15 days. Platelet counts increased by a mean of 6-fold (range: 1.3- to 14.3-fold) in five out of eight evaluable patients. Reticulocyte counts increased 2.9-fold in three patients, and neutrophil counts increased by a mean of 3.1-fold in all eight patients. Platelet transfusions could be discontinued after treatment with rhIL-3 in two out of three evaluable transfusion-dependent patients. Only mild side effects, mainly fever and headache, were observed. These results indicate that rhIL-3 functions as a multilineage hematopoietic growth factor in vivo in patients with secondary bone marrow failure.


Asunto(s)
Enfermedades Hematológicas/tratamiento farmacológico , Interleucina-3/uso terapéutico , Adulto , Anciano , Antineoplásicos/efectos adversos , Recuento de Células Sanguíneas , Médula Ósea/patología , Evaluación de Medicamentos , Femenino , Enfermedades Hematológicas/etiología , Humanos , Interleucina-3/efectos adversos , Masculino , Persona de Mediana Edad , Neoplasias/terapia , Recuento de Plaquetas , Traumatismos por Radiación/complicaciones , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico
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