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21.
In vitro cell culture models can be of great value in order to further analyze the regulatory mechanisms underlying the inappropriate function of the immune system in diseases such as autoimmunity and cancer. Cell culture conditions have to be well controlled in a way that they mirror the in vivo situation. The objective of this study was to compare tissue culture microtiter plates from different manufacturers with respect to their ability to support monokine production by human monocytes cultured in human serum. Tissue culture ware, made of polystyrene, undergoes treatment by the manufacturers to make the surface more suitable for culture of adherent cell populations. It is possible that quality differences in this treatment can lead to variations in protein binding properties and thereby influence the adherence and functional properties of monocytes. We measured spontaneous interleukin-1 receptor antagonist (IL-1ra) production by peripheral blood monocytes, cultured in human serum, in five different microtiter plates made for adherent cell culture. Culture in plates from two of the five manufacturers resulted in significantly lower amounts of secreted IL-1ra. IL-1ra release by human monocytes can be induced by adherent IgG cross-linking membrane receptors for the Fc part of IgG (FcgammaR). We found that reduced IL-1ra production coincided with a reduced capacity for binding of serum IgG in one case. Furthermore, this brand of microtiter plate also displayed the lowest level of adsorption of human albumin. We conclude that the protein adsorption properties of the plastic tissue culture ware have to be taken into consideration when assessing monokine production by human monocytes in vitro. 相似文献
22.
Birgitta Swolin Aleksander Weinfeld Johan Waldenström Jan Westin 《Cancer Genetics and Cytogenetics》1983,9(3):197-209
Of 33 consecutive patients with chronic myelocytic leukemia, examined during metamorphosis, 82% showed chromosome abnormalities in addition to the Ph1. Aberrations most frequently encountered were +8 (39%), +22q - (30%), and i(17q) (18%). Translocations other than the Ph1 were observed in four cases and - Y clones in four cases. Discrepancies in the cytogenetic pattern between bone marrow and extramedullary tissues or blood were noted in a total of 15 patients. In six cases, transformation occurred in extramedullary organs at a time when it was not present in the marrow. In three cases the bone marrow transformation was preceded by a lymph node blastic infiltrate; in one case, by a skin infiltrate; and in one case, by a subdural blastoma. Clonal abnormalities additional to the Ph1 were identified in the tumor tissue from all these cases. Patients with primary extramedullary transformation tended to have a lower median age at onset of metamorphosis, shorter survival, and higher incidence of chromosome abnormalities than the cases without extramedullary involvement. Patients with only Ph1-positive cells and no other anomalies had a slightly longer duration of metamorphosis and longer total survival. Basophilia and thrombocytopenia were more marked in cases with i(17q) than in the rest of the series. 相似文献
23.
John Timothy Wright Mary Fete Holm Schneider Madelaine Zinser Maranke I. Koster Angus J. Clarke Smail Hadj‐Rabia Gianluca Tadini Nina Pagnan Atila F. Visinoni Birgitta Bergendal Becky Abbott Timothy Fete Clark Stanford Clayton Butcher Rena N. D'Souza Virginia P. Sybert Maria I. Morasso 《American journal of medical genetics. Part A》2019,179(3):442-447
An international advisory group met at the National Institutes of Health in Bethesda, Maryland in 2017, to discuss a new classification system for the ectodermal dysplasias (EDs) that would integrate both clinical and molecular information. We propose the following, a working definition of the EDs building on previous classification systems and incorporating current approaches to diagnosis: EDs are genetic conditions affecting the development and/or homeostasis of two or more ectodermal derivatives, including hair, teeth, nails, and certain glands. Genetic variations in genes known to be associated with EDs that affect only one derivative of the ectoderm (attenuated phenotype) will be grouped as non‐syndromic traits of the causative gene (e.g., non‐syndromic hypodontia or missing teeth associated with pathogenic variants of EDA “ectodysplasin”). Information for categorization and cataloging includes the phenotypic features, Online Mendelian Inheritance in Man number, mode of inheritance, genetic alteration, major developmental pathways involved (e.g., EDA, WNT “wingless‐type,” TP63 “tumor protein p63”) or the components of complex molecular structures (e.g., connexins, keratins, cadherins). 相似文献
24.
The effect of dimethylnitrosamine on the nucleosomal structure of mouse liver chromatin was studied. After a single oral dose of dimethylnitrosamine (2–75 mg/kg body weight 45 min before sacrifice) liver nuclei were isolated and incubated with micrococcus nuclease. Nucleosomes were separated on sucrose density gradients. There were no differences in nucleosomal sedimentation velocities between preparations from control and dimethylnitrosamine treated animals. The supernatant obtained after centrifugation of the lysed nuclei (2 min at 4,000 g
av) and nucleosomal peak fractions were used for isolation of DNA. DNA was heat denatured in 7 M urea or formamide. After electrophoresis on polyacrylamide gels areas under mononucleosomal DNA and smaller fragments were measured and compared with the total DNA area. The increase in DNA fragmentation was dimethylnitrosamine dose response dependent. When expressed as per cent of controls it amounted to 106% for 2 mg; 115% for 10 mg; 127% for 25 mg; 164% for 75 mg dimethylnitrosamine/kg body weight. A good correlation between mobility and log of chain length of
174 RF DNA-Hae III digest was obtained in nondenaturing 5% polyacrylamide gels and denaturing non-aqueous formamide polyacrylamide gels but not in 12% polyacrylamide gels containing 7 M urea. DNA of mononucleosomal peak fractions contained 200 and that of dinucleosomal peak fractions 400 nucleotides. Fragmentation of DNA was closely related to in vivo dimethylnitrosamine treatment but was not detected in measurements of protein-DNA complexes in the chromatin. It was disclosed on denaturation of DNA followed by polyacrylamide gel electrophoresis.Abbreviations DMN
dimethylnitrosamine
- SDS
sodium dodecyl sulfate
The work was supported by Grant Number 1 R0 1 CA26642-01, awarded to A.v.d.D. by the National Cancer Institute, DHEW 相似文献
25.
Helén Tuvesson Ingrid Hallin Robert Persson Birgitta Sparre Per Olov Gunnarsson Janeric Seideg?rd 《Drug metabolism and disposition》2005,33(6):866-872
In the present study, the involvement of cytochrome P450 enzyme(s) in the primary metabolism of laquinimod, a new orally active immunomodulator, has been investigated in human liver microsomes. Hydroxylated and dealkylated metabolites were formed. The metabolite formation exhibited single enzyme Michaelis-Menten kinetics with apparent KM in the range of 0.09 to 1.9 mM and Vmax from 22 to 120 pmol/mg/min. A strong correlation between the formation rate of metabolites and 6beta-hydroxylation of testosterone was obtained within a panel of liver microsomes from 15 individuals (r2 = 0.6 to 0.94). Moreover, ketoconazole and troleandomycin, specific inhibitors of CYP3A4 metabolism, demonstrated a significant inhibition of laquinimod metabolism. Furthermore, in incubations with recombinant CYP3A4, all the primary metabolites were formed. In vitro interaction studies with CYP3A4 substrates and possible concomitant medication demonstrated that laquinimod inhibits the metabolism of ethinyl estradiol with an IC50 value of about 150 microM, which is high above the plasma level of laquinimod after clinically relevant doses. Ketoconazole, troleandomycin, erythromycin, prednisolone, and ethinyl estradiol inhibited the metabolism of laquinimod, and IC50 values of 0.2, 11, 24, 87, and 235 microM, respectively, were calculated. In conclusion, the present study demonstrates that laquinimod is a low affinity substrate for CYP3A4 in human liver microsomes. The likelihood for in vivo effects of laquinimod on the metabolism of other CYP3A4 substrates is minor. However, inhibitory effects on the metabolism of laquinimod by potent and specific inhibitors of CYP3A4, such as ketoconazole, are anticipated and should be considered in the continued clinical program for laquinimod. 相似文献
26.
Nina Streefkerk Marianne J. Heins Jop C. Teepen Elizabeth A. M. Feijen Dorine Bresters Eline van Dulmen‐den Broeder Margriet van der Heiden‐van der Loo Marry M. van den Heuvel‐Eibrink Flora E. van Leeuwen Jacqueline J. Loonen Helena J. H. van der Pal Ccile M. Ronckers A. Birgitta Versluys Wim J. E. Tissing Joke C. Korevaar Leontien C. M. Kremer 《Pediatric blood & cancer》2019,66(8)
27.
Damien C. Weber Yucai Wang Robert Miller Salvador Villà Renata Zaucha Alessia Pica Philip Poortmans Yavuz Anacak Gokhan Ozygit Birgitta Baumert Guy Haller Matthias Preusser Jing Li 《Neuro-oncology》2015,17(4):588-595
Background
Spinal myxopapillary ependymomas (MPEs) are slowly growing ependymal gliomas with preferential manifestation in young adults. The aim of this study was to assess the outcome of patients with MPE treated with surgery, radiotherapy (RT), and/or chemotherapy.Methods
The medical records of 183 MPE patients (male: 59%) treated at the MD Anderson Cancer Center and 11 institutions from the Rare Cancer Network were retrospectively reviewed. Mean patient'' age at diagnosis was 35.5 ± 15.8 years. Ninety-seven (53.0%) patients underwent surgery without RT, and 86 (47.0%) were treated with surgery and/or RT. Median RT dose was 50.4 Gy. Median follow-up was 83.9 months.Results
Fifteen (8.2%) patients died, 7 of unrelated cause. The estimated 10-year overall survival was 92.4% (95% CI: 87.7–97.1). Treatment failure was observed in 58 (31.7%) patients. Local failure, distant spinal relapse, and brain failure were observed in 49 (26.8%), 17 (9.3%), and 11 (6.0%) patients, respectively. The estimated 10-year progression-free survival was 61.2% (95% CI: 52.8–69.6). Age (<36 vs ≥36 y), treatment modality (surgery alone vs surgery and RT), and extent of surgery were prognostic factors for local control and progression-free survival on univariate and multivariate analysis.Conclusions
In this series, treatment failure of MPE occurred in approximately one third of patients. The observed recurrence pattern of primary spinal MPE was mainly local, but a substantial number of patients failed nonlocally. Younger patients and those not treated initially with adjuvant RT or not undergoing gross total resection were significantly more likely to present with tumor recurrence/progression. 相似文献28.
29.
30.
Liss Marita Solbakken Birgitta Langhammer Antje Sundseth Therese Brovold 《Health expectations》2022,25(4):1741
BackgroundThe scope of this priority‐setting process is communication and collaboration in transitional care for patients with acute stroke. Actively involving persons with stroke and their family caregivers is important both in transitional care and when setting priorities for research. Established priority‐setting methods are time‐consuming and require extensive resources. They are therefore not feasible in small‐scale research. This article describes a pragmatic priority‐setting process to identify a prioritized top 10 list of research needs regarding transitional care for patients with acute stroke.MethodsA pragmatic priority‐setting approach inspired by the James Lind Alliance was developed. It involves establishing a user group, identifying the research needs through an online survey, analysing and checking the research needs against systematic reviews, culminating in an online prioritization of the top 10 list.ResultsThe process was completed in 7 months. A total of 122 patients, family caregivers, health personnel and caseworkers submitted 484 research needs, and 19 users prioritized the top 10 list. The list includes the categories ‘patients and caregivers’ needs and health literacy’, ‘health personnel''s common understanding’, ‘information flow between health personnel and patients and caregivers’, ‘available interventions and follow‐up of patients and caregivers’, ‘interaction and collaboration between health personnel and caseworkers across hospital and primary healthcare’ and ‘disabilities after stroke’.ConclusionThis paper outlines a pragmatic approach to identifying and prioritizing users'' research needs that was completed in 7 months. The top 10 list resulting from this priority setting process can guide future research relating to communication and collaboration during the transition from hospital to the community for patients with stroke.Patient and Public ContributionMembers of three stroke organizations participated in the advisory group. They gave feedback on the scope and the process, distributed the surveys and prioritized the top 10 list. Persons with stroke and their caregivers submitted research needs in the survey. 相似文献