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1.
Actas Dermosifiliogr ; 2024 Jun 07.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38852841

RESUMEN

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematodermic neoplasm usually involving the skin. In this retrospective case series, 10 cases of BPDCN were identified, 90% of which had skin involvement and exhibited predominantly violaceous nodules and/or bruise-like plaques. Skin lesions showed diffuse or nodular dermal-based infiltrates of intermediate sized blasts with a grenz zone. Tumor immunophenotyping was CD4(+), CD56(+), CD123(+) and CD303(+). The most frequently mutated genes according to targeted next-generation sequencing were TET2 (3/7) and NRAS (2/7). Multiagent chemotherapy (CT) was administered as first-line therapy, and a total of 5 patients underwent allogenic hematopoietic stem cell transplantation (allo-HSCT). Better outcomes were observed in younger patients and those treated with acute lymphoblastic leukemia (ALL)-like CT followed by allo-HSCT. This study shows the clinical range of cutaneous lesions of BPDCN. Despite the absence of a gold standard therapy, patients treated with myeloablative intensive regimens and allo-HSCT seems to have a more favorable prognosis.

2.
Phys Med Biol ; 68(19)2023 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-37747082

RESUMEN

Objective.A new method to estimate the range of an ion beam in a patient during heavy-ion therapy was investigated, which was previously verified for application in proton therapy.Approach.The method consists of placing a hadron tumour marker (HTM) close to the tumour. As the treatment beam impinges on the HTM, the marker undergoes nuclear reactions. When the HTM material is carefully chosen, the activation results in the emission of several delayed, characteristicγrays, whose intensities are correlated with the remaining range inside the patient. When not just one but two reaction channels are investigated, the ratio between these twoγray emissions can be measured, and the ratio is independent of any beam delivery uncertainties.Main results.A proof-of-principle experiment with an16O ion beam and Ag foils as HTM was successfully executed. The107Ag(16O,x)112Sb and the107Ag(16O,x)114Sb reaction channels were identified as suitable for the HTM technique. When only oneγ-ray emission is measured, the resulting range-uncertainty estimation is at the 0.5 mm scale. When both channels are considered, a theoretical limit on the range uncertainty of a clinical fiducal marker was found to be ±290µm.Significance.Range uncertainty of a heavy-ion beam limits the prescribed treatment plan for cancer patients, especially the direction of the ion beam in relation to any organ at risk. An easy to implement range-verification technique which can be utilized during clinical treatment would allow treatment plans to take full advantage of the sharp fall-off of the Bragg peak without the risk of depositing excessive dose into healthy tissue.


Asunto(s)
Radioterapia de Iones Pesados , Terapia de Protones , Humanos , Biomarcadores de Tumor , Radioterapia de Iones Pesados/métodos , Terapia de Protones/métodos , Incertidumbre , Método de Montecarlo
3.
Schweiz Arch Tierheilkd ; 165(2): 127-131, 2023 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-36718714

RESUMEN

INTRODUCTION: Cattle births can carry the risk of transmissible and zoonotic diseases. The focus of the present study was the excretion of Coxiella (C.) burnetii during cattle births. Small ruminants are considered as the main reservoir of C. burnetii. Cattle are often subclinical carriers and their role as potential reservoir has not been fully elucidated until now, although the excretion of Coxiella has been demonstrated during cattle birth. The study recorded all births, caesarean sections and one abortion in 40 cattle at the ruminant clinic of the Vetsuisse Faculty in Bern in the study period from March 2019 to March 2020. A placenta -, milk - and fecal sample was examined for antigen diagnostics using polymerase chain reaction (PCR). In addition, a serum sample was analyzed to detect C. burnetii-specific antibodies. Antigen and/or antibodies (placenta, n=8/9; milk, n=2/9; faeces, n=1/9; serology n= 3/9) were detected in 22,5 % of the cows (n=9/40) without the presence of specific clinical symptoms. It is essential to sensitize contact persons to this zoonosis, since Coxiella can trigger Q-fever in humans.


INTRODUCTION: Les naissances chez les bovins peuvent comporter un risque de maladies transmissibles et zoonotiques. La présente étude se concentre sur l'excrétion de Coxiella (C.) burnetii lors des mises-bas de bovins. Les petits ruminants sont considérés comme le principal réservoir de C. burnetii, mais les bovins sont souvent des porteurs subcliniques et leur rôle de réservoir potentiel n'a pas été complètement élucidé jusqu'à présent, bien que l'excrétion de Coxiella ait été démontrée lors de la mise-bas. L'étude a recensé toutes les naissances, les césariennes et un avortement chez 40 bovins à la Clinique des ruminants de la Faculté Vetsuisse de Berne durant la période allant de mars 2019 à mars 2020. Un échantillon de placenta, de lait et de matières fécales a été examiné pour le diagnostic des antigènes par réaction en chaîne par polymérase (PCR). En outre, un échantillon de sérum a été analysé pour détecter les anticorps spécifiques de C. burnetii. L'antigène et/ou les anticorps (placenta, n=8/9 ; lait, n=2/9 ; fèces, n=1/9 ; sérologie n=3/9) ont été détectés chez 22,5 % des vaches (n=9/40) sans présence de symptômes cliniques spécifiques. Il est essentiel de sensibiliser les personnes de contact à cette zoonose, car Coxiella peut déclencher la fièvre Q chez l'homme.


Asunto(s)
Enfermedades de los Bovinos , Coxiella burnetii , Fiebre Q , Embarazo , Femenino , Animales , Bovinos , Humanos , Enfermedades de los Bovinos/diagnóstico , Fiebre Q/diagnóstico , Fiebre Q/epidemiología , Fiebre Q/veterinaria , Rumiantes , Zoonosis
5.
Phys Chem Chem Phys ; 24(44): 27121-27127, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36342321

RESUMEN

During the last decade, X-ray free-electron lasers (XFELs) have enabled the study of light-matter interaction under extreme conditions. Atoms which are subject to XFEL radiation are charged by a complex interplay of (several subsequent) photoionization events and electronic decay processes within a few femtoseconds. The interaction with molecules is even more intriguing, since intricate nuclear dynamics occur as the molecules start to dissociate during the charge-up process. Here, we demonstrate that by analyzing photoelectron angular emission distributions and kinetic energy release of charge states of ionic molecular fragments, we can obtain a detailed understanding of the charge-up and fragmentation dynamics. Our novel approach allows for gathering such information without the need of complex ab initio modeling. As an example, we provide a detailed view on the processes happening on a femtosecond time scale in oxygen molecules exposed to intense XFEL pulses.

6.
Rev Sci Instrum ; 93(1): 013306, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35104937

RESUMEN

A challenge preventing successful inverse kinematics measurements with heavy nuclei that are not fully stripped is identifying and tagging the beam particles. For this purpose, the HEavy ISotope Tagger (HEIST) has been developed. HEIST utilizes two micro-channel plate timing detectors to measure the time-of-flight, a multi-sampling ion chamber to measure energy loss, and a high-purity germanium detector to identify isomer decays and calibrate the isotope identification system. HEIST has successfully identified 198Pb and other nearby nuclei at energies of about 75 MeV/A. In the experiment discussed, a typical cut containing 89% of all 198Pb80+ in the beam had a purity of 86%. We examine the issues of charge state contamination. The observed charge state populations of these ions are presented and, using an adjusted beam energy, are well described by the charge state model GLOBAL.

7.
Phys Rev E ; 102(5-1): 051201, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33327093

RESUMEN

Experiments on the National Ignition Facility (NIF) to study hohlraums lined with a 20-mg/cc 400-µm-thick Ta_{2}O_{5} aerogel at full scale (hohlraum diameter = 6.72 mm) are reported. Driven with a 1.6-MJ, 450-TW laser pulse, the performance of the foam liner is diagnosed using implosion hot-spot symmetry measurements of the high-density carbon (HDC) capsule and measurement of inner beam propagation through a thin-wall 8-µm Au window in the hohlraum. Results show an improved capsule performance due to laser energy deposition further inside the hohlraum, leading to a modest increase in x-ray drive and reduced preheat due to changes in the x-ray spectrum when the foam liner is included. In addition, the outer cone bubble uniformity is improved, but the predicted improvement in inner beam propagation to improve symmetry control is not realized for this foam thickness and density.

8.
Science ; 369(6511): 1630-1633, 2020 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-32973029

RESUMEN

Addressing the ultrafast coherent evolution of electronic wave functions has long been a goal of nonlinear x-ray physics. A first step toward this goal is the investigation of stimulated x-ray Raman scattering (SXRS) using intense pulses from an x-ray free-electron laser. Earlier SXRS experiments relied on signal amplification during pulse propagation through dense resonant media. By contrast, our method reveals the fundamental process in which photons from the primary radiation source directly interact with a single atom. We introduce an experimental protocol in which scattered neutral atoms rather than scattered photons are detected. We present SXRS measurements at the neon K edge and a quantitative theoretical analysis. The method should become a powerful tool in the exploration of nonlinear x-ray physics.

9.
J Eur Acad Dermatol Venereol ; 34(12): 2884-2889, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32367562

RESUMEN

BACKGROUND: Rituximab induces a rapid remission in most patients with pemphigus. OBJECTIVE: Our aim was to assess the long-term efficacy of rituximab in this disease. METHOD: We conducted a retrospective study of 59 patients with pemphigus treated with rituximab and observed over a median period of 104 months. RESULTS: The rate of complete remission off therapy (CRoff) after the first rituximab cycle was 39%, increasing to 61% with additional rituximab courses. Long-term CRoff was achieved in 27% of patients. The recurrence rate after the first rituximab cycle was 63%, decreasing to approximately 40% with subsequent rituximab cycles. Median time to relapse after the first and subsequent rituximab cycles was 25 months. Renewed rituximab therapy reinduced complete remission in 94% of cases. Baseline anti-desmoglein antibody levels of ≤250 U/mL were significantly associated with the outcome of CRoff. In paired serum samples obtained before the first and six months after the last rituximab therapy, significant reductions of desmoglein-specific autoantibodies were observed. Patients relapsing after a complete remission induced by the first rituximab cycle were more likely to achieve CRoff than patients relapsing after a less favourable outcome and non-responders. There was no significant difference in age, sex, pemphigus subtype, rituximab dosing and disease duration between patients achieving CRoff and those not meeting this end point. CONCLUSIONS: Lower desmoglein-specific antibody levels at baseline were predictive of CRoff. In patients receiving multiple rituximab cycles, complete remission after the first cycle was associated with a favourable long-term outcome. Repeated rituximab courses were highly effective for relapsed disease and improved the overall outcome.


Asunto(s)
Pénfigo , Humanos , Factores Inmunológicos/uso terapéutico , Pénfigo/tratamiento farmacológico , Inducción de Remisión , Estudios Retrospectivos , Rituximab , Resultado del Tratamiento
10.
Ann Hematol ; 99(7): 1627-1634, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32451707

RESUMEN

There is no standard treatment for relapsed follicular lymphoma (FL). Although platinum-based combinations are one of the most used treatments, few data have been reported in this setting. Our aim was to analyse R-ESHAP efficacy in relapsed FL patients. We retrospectively analysed 80 FL patients treated with R-ESHAP in the first or successive relapses. Responding patients received a stem cell transplantation following R-ESHAP. Seventeen histologically transformed patients were included. Median age was 50 years. At R-ESHAP initiation, 85% of the patients were in an advanced stage, 28% had a bulky disease and 40% had increased LDH. There were no statistically significant differences between POD24 and non-POD24 patients in terms of response to R-ESHAP (ORR 72% vs. 93%, p = 0.109). When analyzing R-ESHAP efficacy according to the response to the immediately previous line, patients achieving CR or PR had better CR rates to R-ESHAP than those who did not respond (CR of 57% vs. 15%, respectively, p = 0.009), as well as differences in OS (7.2 vs. 1.4 years, p < 0.0001) and in PFS (2.1 vs. 0.3 years, p < 0.0001). R-ESHAP is an effective treatment in relapsed FL patients who respond to the previous line and has to be considered as an adequate alternative for some patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Linfoma Folicular/tratamiento farmacológico , Linfoma Folicular/patología , Rituximab/administración & dosificación , Terapia Recuperativa/métodos , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Citarabina/administración & dosificación , Citarabina/efectos adversos , Progresión de la Enfermedad , Resistencia a Antineoplásicos/efectos de los fármacos , Etopósido/administración & dosificación , Etopósido/efectos adversos , Femenino , Humanos , Linfoma Folicular/mortalidad , Masculino , Metilprednisolona/administración & dosificación , Metilprednisolona/efectos adversos , Persona de Mediana Edad , Clasificación del Tumor , Recurrencia , Estudios Retrospectivos , Rituximab/efectos adversos , España/epidemiología , Análisis de Supervivencia , Insuficiencia del Tratamiento , Resultado del Tratamiento , Adulto Joven
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