Evaluation of AQUIOS STEM, a novel method for automated CD34+ stem cell enumeration using flow cytometry.

OBJECTIVES: Hematopoietic stem cell transplantation (HSCT) is a potentially curative treatment for various diseases. The measurement of CD34+ cells is crucial to schedule the peripheral blood stem cell collection and assess the engraftment potential of the apheresis product. The AQUIOS STEM system has been introduced as a novel application on the AQUIOS CL, a fully automated flow cytometer, for the enumeration of CD34+ hematopoietic progenitor cells (HPCs) in accordance with the The International Society for Hematotherapy and Graft Engineering guidelines. This study aimed to assess the potential of the novel AQUIOS STEM system versus currently used systems including the FACSCanto-II and the FACS Lyric flow cytometer in a multicenter study. METHODS: A total of 91 samples were used for the validation of the AQUOIS STEM system, including an analytical performance evaluation by means of assessing precision, sample stability, intersample carryover, and linearity and a method comparison with the present FACS systems in use to assess analytical and clinical decision agreement. RESULTS: Results showed excellent precision, with coefficient of variations <15% for dedicated quality control material and patient samples. There was no significant carry over. The fresh apheresis samples were stable when stored overnight at room temperature and at 4°C. Analytical comparison with the current systems demonstrated good correlation in peripheral blood, and minimal, clinically neglectable systematic and proportional bias in fresh apheresis products but a low correlation coefficient in cryopreserved products. CONCLUSIONS: The STEM system on AQUIOS CL allows automated enumeration of CD34+ stem cells, demonstrating good analytical performance and promising overall outcomes in peripheral blood and fresh apheresis products.

Learning the Chymical Compromise: Paracelsian and Galenic Medicine in Marburg Disputations on Chymiatria.

The chair of chymiatria created at the University of Marburg was among the earliest academic initiatives aiming to integrate chymistry into the medical curriculum. If its practical applications in pharmacy and its relationship with patronage have been examined by historians, the theoretical part of the chymiatria programme still remains to be explored. In the form of student disputations and dissertations held or presided over by Heinrich Petraeus, a professor of medicine at Marburg and Johannes Hartmann's son-in-law, "chymiatric" essays expounded various medical issues. Centred on pathology, therapy, and physiology, these theoretical explanations proposed a "hermetic-dogmatic" interpretation merging the views of Paracelsus and Galen. This article examines these disputations and their stance concerning the living body, sickness, and treatment, and how they shaped the status of chymistry as an art and a science on the verge of institutionalisation.

Evaluation of a worldwide EQA scheme for complex clonality analysis of clinical lymphoproliferative cases demonstrates a learning effect.

Clonality analysis of immunoglobulin (IG) or T-cell receptor (TR) gene rearrangements is routine practice to assist diagnosis of lymphoid malignancies. Participation in external quality assessment (EQA) aids laboratories in identifying systematic shortcomings. The aim of this study was to evaluate laboratories' improvement in IG/TR analysis and interpretation during five EQA rounds between 2014 and 2018. Each year, participants received a total of five cases for IG and five cases for TR testing. Paper-based cases were included for analysis of the final molecular conclusion that should be interpreted based on the integration of the individual PCR results. Wet cases were distributed for analysis of their routine protocol as well as evaluation of the final molecular conclusion. In total, 94.9% (506/533) of wet tests and 97.9% (829/847) of paper tests were correctly analyzed for IG, and 96.8% (507/524) wet tests and 93.2% (765/821) paper tests were correctly analyzed for TR. Analysis scores significantly improved when laboratories participated to more EQA rounds (p=0.001). Overall performance was significantly lower (p=0.008) for non-EuroClonality laboratories (95% for IG and 93% for TR) compared to EuroClonality laboratories (99% for IG and 97% for TR). The difference was not related to the EQA scheme year, anatomic origin of the sample, or final clinical diagnosis. This evaluation showed that repeated EQA participation helps to reduce performance differences between laboratories (EuroClonality versus non-EuroClonality) and between sample types (paper versus wet). The difficulties in interpreting oligoclonal cases highlighted the need for continued education by meetings and EQA schemes.

Minimal Coexpression of CD34+/CD56+ in Acute Promyelocytic Leukemia Is Associated With Relapse.

OBJECTIVES: Surface CD56 expression on leukemic cells in acute promyelocytic leukemia (APML) is considered an indicator of poorer outcome even in patients receiving conventional treatment. METHODS: In the present case, at initial diagnosis, the hallmark phenotype of APML was found (strong CD33 and cytoplasmic MPO expression, absence of HLA-DR expression). RESULTS: Both CD34 and CD56 antigen expression was considered negative. The patient relapsed 3 years after reaching complete remission, and the hallmark surface antigen combination for APML was again found. In contrast, the leukemic cells now clearly coexpressed CD34 and CD56. Retrospective analysis revealed the presence of small CD34+ and CD56+ populations at initial diagnosis (<20%). CONCLUSIONS: This case report suggests that the presence of a clone with minimal coexpression of CD34/CD56 in APML at initial diagnosis should not be neglected since it may be associated with earlier relapse.

Biocompatibility of polycations: in vitro agglutination and lysis of red blood cells and in vivo toxicity.

The effects of six polycations were studied in vitro on red blood cells (RBC) and in vivo after intravenous administration. Hemagglutination and hemolysis depended not only on the molar mass and the concentration of these polycations, but also on their chemical nature. The hemagglutination and hemolysis induced by poly(L-lysine), diethylaminoethyldextran, poly(dimethyldiallylammonium) chloride and poly[2-(dimethylamino)ethyl methacrylate] was low to moderate, whereas a severe hemolysis was induced by a partially quaternized poly[thio-1-(N,N-diethyl-aminoethyl)ethylene]. In the case of poly(epsilon-lysine), no significant hemagglutination nor hemolysis was observed. The presence of plasma proteins reduced both agglutination and hemolysis. This protective effect was enhanced when the polycations interacted with plasma proteins before contact with RBC. In the presence of albumin, the behavior depended on the polycation and on the order of addition of the three components of the suspension, namely albumin, polycation and RBC. Depending on the polycation, albumin-polycation complexes were either less active or more active on RBC than the same polycation in protein-free medium. In vivo the studied polycations induced an immediate mortality except poly(epsilon-lysine), which induced a delayed mortality. The minimal dose of polycations inducing immediate mortality paralleled their effect on RBC.

[The Galenic content of Isaac Beeckman's medical ideas (1617-1629)]. / Le substrat galénique des idées médicales d'Isaac Beeckman (1616-1627).

The Journal tenu par Isaac Beeckman de 1604 à 1634 has been studied in the history of the seventeenth-century scientific revolution following the theme of Isaac Beeckman's physical mathematical mechanistic view, his proto-molecular theory and his atomistic Lucretian influence. This article goes deeper into the medical ideas of the Journal: how Isaac Beeckman (1588-1637) settles the structure of living matter according to his intensive reading of Galen. It develops a different analysis from the traditionally triumphalist approach in the history of science, focused on the victory of Cartesian mechanism, particularly in the history of medicine taking up Galenism very briefly because of its obsolete physiology. The Galenic corpus inside Isaac Beeckman's Journal consists of the many commentaries of Galen which Beeckman has put down in writing since 1616 until 1627, after when the passages linked to Galen became fewer. Isaac Beeckman's study of Galenic medicine is analyzed according to three approaches: the teleological dimension of Galenism showing up the organic conception of human body corresponding to the divine Providence and consistent with Beeckman's Calvinist belief, the physiologic angle of Galenism, based on natural faculties, stressing the purely speculative aspect of Beeckman's commentaries, while the pathologic and therapeutic angle supports the Hippocratic humourism influence.

A diffusible signal from germinating Orobanche ramosa elicits early defense responses in suspension-cultured Arabidopsis thaliana.

In plant/parasitic plant interaction, little is known about the host plant response before the establishment of the parasite within the host. In the present work, we focused on host responses to parasitic plant, O. ramosa in the early stage of infection. We used a co-culture system of A. thaliana suspension cells and O. ramosa germinated-seeds to avoid parasite attachment. We showed that O. ramosa induced H(2)O(2) generation and camalexin synthesis by A. thaliana followed by a drastic increase in cell death. We further demonstrated that a heat sensitive diffusible signal is responsible for this cell death. These data indicate that recognition of O. ramosa occurs before the attachment of the parasite and initiates plant defence responses.

Characterization of a new, nonpathogenic mutant of Botrytis cinerea with impaired plant colonization capacity.

Botrytis cinerea is a necrotrophic pathogen that attacks more than 200 plant species. Here, the nonpathogenic mutant A336, obtained via insertional mutagenesis, was characterized. Mutant A336 was nonpathogenic on leaves and fruits, on intact and wounded tissue, while still able to penetrate the host plant. It grew normally in vitro on rich media but its conidiation pattern was altered. The mutant did not produce oxalic acid and exhibited a modified regulation of the production of some secreted proteins (acid protease 1 and endopolygalacturonase 1). Culture filtrates of the mutant triggered an important oxidative burst in grapevine (Vitis vinifera) suspension cells, and the mutant-plant interaction resulted in the formation of hypersensitive response-like necrosis. Genetic segregation analyses revealed that the pathogenicity phenotype was linked to a single locus, but showed that the mutated gene was not tagged by the plasmid pAN7-1. Mutant A336 is the first oxalate-deficient mutant to be described in B. cinerea and it differs from all the nonpathogenic B. cinerea mutants described to date.