Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
1.
Rev Sci Instrum ; 93(12): 125106, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36586895

RESUMEN

We introduce the setup of a versatile sample chamber for x-ray scattering experiments on liquids delivered by µ-jets. The simple implementation at x-ray light sources, adaptability to different nozzle types, and the availability of a microscope for observation of the jet flow allow for its broad application. In combination with an inbuilt recycling circle, a continuous flow operation is provided. Functionality of the system was demonstrated in a rheology study at PETRA III.

2.
Blood ; 140(20): 2113-2126, 2022 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-35704690

RESUMEN

The BCL2 inhibitor venetoclax has been approved to treat different hematological malignancies. Because there is no common genetic alteration causing resistance to venetoclax in chronic lymphocytic leukemia (CLL) and B-cell lymphoma, we asked if epigenetic events might be involved in venetoclax resistance. Therefore, we employed whole-exome sequencing, methylated DNA immunoprecipitation sequencing, and genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 screening to investigate venetoclax resistance in aggressive lymphoma and high-risk CLL patients. We identified a regulatory CpG island within the PUMA promoter that is methylated upon venetoclax treatment, mediating PUMA downregulation on transcript and protein level. PUMA expression and sensitivity toward venetoclax can be restored by inhibition of methyltransferases. We can demonstrate that loss of PUMA results in metabolic reprogramming with higher oxidative phosphorylation and adenosine triphosphate production, resembling the metabolic phenotype that is seen upon venetoclax resistance. Although PUMA loss is specific for acquired venetoclax resistance but not for acquired MCL1 resistance and is not seen in CLL patients after chemotherapy-resistance, BAX is essential for sensitivity toward both venetoclax and MCL1 inhibition. As we found loss of BAX in Richter's syndrome patients after venetoclax failure, we defined BAX-mediated apoptosis to be critical for drug resistance but not for disease progression of CLL into aggressive diffuse large B-cell lymphoma in vivo. A compound screen revealed TRAIL-mediated apoptosis as a target to overcome BAX deficiency. Furthermore, antibody or CAR T cells eliminated venetoclax resistant lymphoma cells, paving a clinically applicable way to overcome venetoclax resistance.


Asunto(s)
Neoplasias Hematológicas , Leucemia Linfocítica Crónica de Células B , Linfoma de Células B Grandes Difuso , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Resistencia a Antineoplásicos/genética , Proteínas Reguladoras de la Apoptosis/genética , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Linfoma de Células B Grandes Difuso/patología , Neoplasias Hematológicas/tratamiento farmacológico , Neoplasias Hematológicas/genética , Epigénesis Genética
3.
Blood ; 138(23): 2396-2407, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34424959

RESUMEN

Mastocytosis is a heterogeneous disease characterized by an abnormal accumulation of mast cells (MCs) in 1 or several organs. Although a somatic KIT D816V mutation is detected in ∼85% of patients, attempts to demonstrate its oncogenic effect alone have repeatedly failed, suggesting that additional pathways are involved in MC transformation. From 3 children presenting with both Greig cephalopolysyndactyly syndrome (GCPS, Mendelian Inheritance in Man [175700]) and congenital mastocytosis, we demonstrated the involvement of the hedgehog (Hh) pathway in mastocytosis. GCPS is an extremely rare syndrome resulting from haploinsufficiency of GLI3, the major repressor of Hh family members. From these familial cases of mastocytosis, we demonstrate that the Hh pathway is barely active in normal primary MCs and is overactive in neoplastic MCs. GLI3 and KIT mutations had a synergistic, tumorigenic effect on the onset of mastocytosis in a GCPS mouse model. Finally, Hh inhibitors suppressed neoplastic MC proliferation in vitro and extend the survival time of mice with aggressive systemic mastocytosis (ASM). This work revealed, for the first time, the involvement of Hh signaling in the pathophysiology of mastocytosis and demonstrated the cooperative effects of the KIT and Hh oncogenic pathways in mice with ASM, leading to the identification of new promising therapeutic targets.


Asunto(s)
Acrocefalosindactilia/complicaciones , Proteínas Hedgehog/metabolismo , Mastocitosis/complicaciones , Transducción de Señal , Acrocefalosindactilia/metabolismo , Animales , Células Cultivadas , Niño , Humanos , Mastocitosis/metabolismo , Ratones Endogámicos C57BL , Ratones SCID , Células Tumorales Cultivadas
4.
Struct Dyn ; 7(5): 054901, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33094129

RESUMEN

We applied shear to a silica nanoparticle dispersion in a microfluidic jet device and observed direction-dependent structure along and across the flow direction. The asymmetries of the diffraction patterns were evaluated by x-ray cross correlation analysis. For different Rayleigh nozzle sizes and shapes, we measured the decay of the shear-induced ordering after the cessation of the shear. At large tube sizes and small shear rates, the characteristic times of the decay become longer, but Péclet-weighted times do not scale linearly with Péclet numbers. By modeling particle distributions with the corresponding diffraction patterns and comparing measured shape asymmetry to simulations, we determined the variation of volume fraction over the azimuthal angle for the maximum ordered state in the jet.

5.
Eur J Nucl Med Mol Imaging ; 42(13): 2013-20, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26140850

RESUMEN

INTRODUCTION: Mastocytosis is a clonal haematological disease characterized by uncontrolled proliferation and the activation of mast cells. The value of FDG-PET/CT (FDG-PET) in mastocytosis has yet to be determined. METHODS: We retrospectively identified patients with an established diagnosis of systemic mastocytosis (SM), according to the WHO criteria, who underwent PET using the French Reference Centre for Mastocytosis database. Semi-quantitative and visual analysis of FDG-PET was performed and compared to the clinico-biological data. RESULTS: Our cohort included 19 adult patients, median age 65 years [range 58-74], including three with smouldering SM (SSM), three with aggressive SM (ASM), 10 with an associated clonal haematological non-mast-cell lineage disease (SM-AHNMD), and three with mast cell sarcoma (MCS). FDG-PET was performed at the time of the SM diagnosis (15/19), to evaluate lymph node (LN) activity (3/19) or the efficacy of therapy (1/19). FDG uptake was observed in the bone marrow (BM) (9/19, 47%), LN (6/19, 32%), spleen (12/19, 63%), or liver (1/19, 5%). No significant FDG uptake was observed in the SSM and ASM patients. A pathological FDG uptake was observed in the BM of 6/10 patients with SM-AHNMD, appearing as diffuse and homogeneous, and in the LN of 5/10 patients. All 3 MCS patients showed intense and multifocal BM pathological uptake, mimicking metastasis. No correlation was found between the FDG-PET findings and serum tryptase levels, BM mast cell infiltration percentage, and CD30 and CD2 expression by mast cells. CONCLUSIONS: FDG uptake does not appear to be a sensitive marker of mast cell activation or proliferation because no significant FDG uptake was observed in most common forms of mastocytosis (notably purely aggressive SM). However, pathological FDG uptake was observed in the SM-AHNMD and in MCS cases, suggesting a role of FDG-PET in their early identification and as a tool of therapeutic assessment in this subgroup of patients.


Asunto(s)
Mastocitosis Sistémica/diagnóstico por imagen , Imagen Multimodal , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Anciano , Femenino , Fluorodesoxiglucosa F18 , Francia , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos
6.
Mediators Inflamm ; 2015: 792173, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25922564

RESUMEN

BACKGROUND: There are few data on anakinra use after failure of conventional medications for crystal-induced peripheral arthritis and/or crowned dens syndrome among complex hospitalized patients. METHODS: We retrospectively analyzed the outcome of six patients affected with subacute crystal-induced arthritis who had received anakinra in second or third line therapy, including three patients with crowned dens syndrome and three others with gouty arthritis. Patients' comorbidities, reasons for anakinra use and associated drugs, and outcomes were recorded. RESULTS: All patients presented with elevated inflammatory syndrome, systemic symptoms with poly/oligoarthritis. Except for absolute contraindications, all patients were previously treated with full or decreased dose of NSAID, colchicine, and/or glucocorticoids, with unsatisfactory response. All three gouty patients exhibited complete responses in all acute involvements under anakinra within 3 to 5 days, including one of them who needed the reintroduction of colchicine treatment that was previously unsuccessful. Crowned dens syndrome patients, including two with pseudogout and one with subacute hydroxyapatite deposition disease, needed 9 to 11 days to achieve complete response. Tolerance to anakinra was good. CONCLUSION: In case series of complex hospitalized patients, anakinra showed good activity in crowned dens syndrome and associated crystal-induced peripheral arthritis, with longer treatment duration than in gouty arthritis.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Gotosa/tratamiento farmacológico , Artritis/tratamiento farmacológico , Proteína Antagonista del Receptor de Interleucina 1/uso terapéutico , Anciano , Antiinflamatorios no Esteroideos/uso terapéutico , Proteína C-Reactiva/metabolismo , Colchicina/uso terapéutico , Comorbilidad , Femenino , Glucocorticoides/uso terapéutico , Hospitalización , Humanos , Inflamación/tratamiento farmacológico , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
7.
Leukemia ; 29(4): 981-4, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25376373
8.
Haemophilia ; 21(1): 27-33, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25545300

RESUMEN

The choice of plasma-derived products (PdP) vs. recombinant products (RP) for treating haemophilia is influenced by the infectious and perceived safety of the products. Batch recall of PdP due to the risk of variant Creutzfeldt-Jakob disease (vCJD) may have unfavourable psychological impacts on haemophilia patients and influence their product preferences. This study aimed to assess the psychological impact of batch recalls of PdP in six haemophilia patients and their therapeutic demands, and to discuss the ethical problems in physicians' management of this event. A survey was conducted using a new interview form and an existing anxiety and depression questionnaire. Batch recalls produce recurrent negative emotional outcomes in haemophiliacs and their families. The quality, understanding and efficiency of the batch recall announcements were unsatisfactory in some respects. Only one patient still had some of the vials in question, and only three patients understood the real reason for the batch recall. Four patients asked to change their PdP for RP; a fifth patient was considering doing so. Here, topics for discussion include the delivery of an unclear message to patients about a very uncertain risk of a frightening disease, the reasons to maintain PdP when RP are largely available, except in specific cases, and the related discomfort for caregivers. The ethical questions revealed by batch recalls and the high psychological impact of vCJD risk on patients can no longer be ignored, and require surveys assessing the rationales and choices of the healthcare authorities, manufacturers, prescribers and users.


Asunto(s)
Síndrome de Creutzfeldt-Jakob/etiología , Hemofilia A/psicología , Hemofilia A/terapia , Reacción a la Transfusión , Adulto , Niño , Preescolar , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Encuestas y Cuestionarios
9.
J Anim Sci ; 91(10): 5026-36, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23942718

RESUMEN

This survey consisted of data collected from 23 beef harvest plants to document transportation procedures, management practices, and health assessments of market beef and dairy cows and bulls (about n ≅ 7,000 animals). Gooseneck/bumper-pulled trailers were used more often to transport dairy cattle than beef cattle to market whereas tractor-trailers were used more often to transport beef cattle than dairy cattle. All loads (n = 103) met the American Meat Institute Foundation guidelines for spacing. Loads where more than 3% of the cattle slipped during unloading were observed in 27.3% of beef loads and 29.0% of the dairy loads. Beef loads had numerically greater usage of electrical prods (32.4%) versus dairy loads (15.4%) during unloading and were more likely to have a variety of driving aids used more aggressively on them. Fewer cattle had horns, brands, and mud/manure contamination on hides than in the previous survey in 1999. The predominant hide color for beef cows was black (44.2%) whereas the predominant color for dairy cows was the Holstein pattern (92.9%). Fewer cattle displayed evidence of bovine ocular neoplasia (2.9%) than in previous surveys in 1994 (8.5%) and 1999 (4.3%). Knots on live cattle were found less in the round (0.5%) and more in the shoulder region (4.6%) than in 1999 (1.4% and 0.4%, respectively). Dairy cows were more frequently lame in 2007 (48.7%) than 1999 (39.2%) whereas beef cows had numerically less lameness (16.3% vs. 26.6%, respectively). Most beef cows (62.3%) and dairy cows (68.9%) received midpoint body condition scores (3, 4, and 5 for beef; 2 and 3 for dairy). Beef cows had higher numerical percentages of no defects present (72.0%) versus dairy cows (63.0%) when evaluated for a variety of reproductive, health, or management conditions. Continued improvements in several key factors related to transportation, management, and health were observed in this survey, which could result in increased value in market beef and dairy cows and bulls.


Asunto(s)
Crianza de Animales Domésticos , Bienestar del Animal , Bovinos/fisiología , Industria Lechera , Transportes/normas , Animales , Femenino , Masculino , Estados Unidos
10.
Haemophilia ; 19(1): 157-60, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22889018

RESUMEN

Obturator muscles haematoma are rarely reported. The most often reported cases are primary pyomyositis or posttraumatic haematomas occurring during pelvic fractures. We firstly report herein two cases of spontaneous obturator internus haematoma (OIH) in two haemophiliacs with inhibitor. Clinical data and imaging of two patients treated in our clinic are reported here according to previously defined criteria of OIH in posttraumatic situation. Both patients were children suffering from severe and moderate haemophilia A, respectively, with an inhibitor at the time of the event. The clinical feature was marked by an iliopelvic pain letting discussing hip haemarthrosis, appendicitis or iliopsoas haematoma. For both patients ultrasonography (US) failed to provide the diagnosis. Careful and repeated clinical examinations eventually lead to suspect obturator haematoma which was confirmed by abdominopelvic computed tomography (CT) and magnetic resonance imaging (MRI). Respectively, high dose of FVIII or rFVIIa regimen allowed a rapid control of the muscular bleeding in the low and high responder inhibitor patients. Spontaneous OIH may be added to the differential diagnosis of iliopelvic pain in severe forms of haemophilia. US still often performed at first in such case remains unhelpful; abdominopelvic CT or MRI should be performed to discriminate among different diagnoses, including OIH which stays probably undiagnosed.


Asunto(s)
Hematoma/etiología , Hemofilia A/complicaciones , Músculos Psoas , Adolescente , Niño , Humanos , Masculino
12.
Leukemia ; 25(1): 89-100, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20944678

RESUMEN

The pharmacological induction of apoptosis in neoplastic B cells presents a promising therapeutic avenue for the treatment of chronic lymphocytic leukemia (CLL). We profiled a panel of clinical multi-kinase inhibitors for their ability to induce apoptosis in primary CLL cells. Whereas inhibitors targeting a large number of receptor and intracellular tyrosine kinases including c-KIT, FLT3, BTK and SYK were comparatively inactive, the CDK inhibitors BMS-387032 and flavopiridol showed marked efficacy similar to staurosporine. Using the kinobeads proteomics method, kinase expression profiles and binding profiles of the inhibitors to target protein complexes were quantitatively monitored in CLL cells. The targets most potently affected were CDK9, cyclin T1, AFF3/4 and MLLT1, which may represent four subunits of a deregulated positive transcriptional elongation factor (p-TEFb) complex. Albeit with lower potency, both drugs also bound the basal transcription factor BTF2/TFIIH containing CDK7. Staurosporine and geldanamycin do not affect these targets and thus seem to exhibit a different mechanism of action. The data support a critical role of p-TEFb inhibitors in CLL that supports their future clinical development.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteómica , Apoptosis/efectos de los fármacos , Flavonoides/uso terapéutico , Humanos , Leucemia Linfocítica Crónica de Células B/patología , Oxazoles/uso terapéutico , Piperidinas/uso terapéutico , Factor B de Elongación Transcripcional Positiva/antagonistas & inhibidores , Tiazoles/uso terapéutico
13.
Artículo en Ruso | MEDLINE | ID: mdl-1664595

RESUMEN

The immunity indicators (T general, T active and B lymphocytes, IgA, IgM and IgG, phagocytosis intensity and activity) and blood content of medium-size molecules (MSM) were studied in patients with brain tumors. Immunity disturbances were revealed in 96 +/- 4% of the patients whereas the increase of the content of MSM was detected in all the patients. The ratio of the absolute count of B lymphocytes to the count of T general lymphocytes (B/T) was offered for use. The magnitude of the ratio equal to 0.47-0.85 turned out characteristic of malignant tumors. The presence of MSM ranging within 0.390-0.480 units was common to the same tumors. The simultaneous demonstration of the characteristic magnitudes of the B/T and MSM in the patient permits one to reliably differentiate between malignant and benign brain tumors. The high magnitudes of MSM are prognostically unfavourable as regards the patients' survival after surgery.


Asunto(s)
Neoplasias Encefálicas/inmunología , Inmunidad/inmunología , Toxinas Biológicas/sangre , Adolescente , Adulto , Linfocitos B/inmunología , Neoplasias Encefálicas/sangre , Humanos , Inmunoglobulinas/análisis , Recuento de Leucocitos , Persona de Mediana Edad , Peso Molecular , Fagocitosis/inmunología , Linfocitos T/inmunología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...