Puerperal Thromboembolic Disease in “High Risk” Cases

One hundred obstetric patients were studied for evidence of puerperal thromboembolic disease. Only one case of deep vein thrombosis was detected in patients thought to be in a “high risk” category because of age or operative intervention. Clinical findings were unreliable compared with measurements of ¹²⁵I-labelled fibrinogen uptake. Doppler ultrasound flow detection proved a simple screening technique but produced no abnormal findings in this series.     

Spinach Leaves Desaturate Exogenous [C]Palmitate to Hexadecatrienoate : Evidence that de Novo Glycerolipid Synthesis in Chloroplasts Can Utilize Free Fatty Acids Imported from Other Cellular Compartments

Long-chain ¹⁴C-fatty acids applied to the surface of expanding spinach leaves were incorporated into all major lipid classes. When applied in diethyleneglycol monomethyl ether solution, as done by previous workers, [¹⁴C]palmitic acid uptake was much lower than that of [¹⁴C] oleic acid. However, when applied in a thin film of liquid paraffin the rate of [¹⁴C] palmitic acid metabolism was rapid and virtually complete. Considerable radioactivity from [¹⁴C]palmitate incorporated into lipids following either application method gradually appeared in polyunsaturated C₁₆ fatty acids esterified to those molecular species of galactolipids previously thought to be made using only fatty acids synthesized and retained within the chloroplast. Evidence for the incorporation of radioactivity from exogenous [¹⁴C]oleate into those same molecular species of galactolipids was less compelling. The unexpected availability of fatty acids bound to extrachloroplastidal lipids for incorporation into galactolipids characteristically assembled entirely within the chloroplast emphasizes the need to reassess interrelations between the “prokaryotic” and “eukaryotic” pathways of galactolipid formation.     

Immunological detection of residual leukaemic disease in the bone marrow of children with acute lymphoblastic leukaemia

Peripheral blood lymphocytes incubated with tumour cells or extracts may undergo blastogenesis. This is the basis of a technique studied in children with acute lymphoblastic leukaemia (ALL) in childhood in an attempt to predict relapse. Samples of peripheral blood and bone marrow from 82 children with varying degrees of ALL were analysed. Cultures were prepared by incubating a lymphocyte suspension with an autologous bone-marrow suspension. Final ratios of lymphocytes to bone-marrow cells (L: BM) were 1: 1 and 2: 1. Control wells received bone-marrow or lymphocyte suspension only. Cultures were incubated for 72, 96, and 120 hours. All were pulse-labelled with ³H-TdR and radioactivity was measured by scintillation counting. Results were expressed as the stimulation index, calculated by dividing the mean counts per minute (cpm) of wells containing both lymphocytes and bone-marrow cells by the sum of the mean cpm for control wells. If the stimulation index exceeded 1 at 72, 96, or 120 hours at either L: BM ratio a positive response was recorded.Seventy-six children were in clinical remission at the time of testing (group A) and six were in clinical relapse (group B). In group A 24 patients showed stimulation and relapsed later at a mean time of 3·8 months (21 with marrow disease, two with testicular infiltration, and one with lung infiltration). Sixteen patients showed stimulation and had up to 4% blasts in their bone marrow but remained in remission. Nineteen other patients showed a positive response and several factors may have contributed to this: two underwent a “rebound” lymphocytosis after stopping treatment, nine had current or intercurrent infections, two had persistent unexplained bone-marrow lymphocytosis, but six had no causative symptoms and thus their responses were “true false-positives.” Seventeen patients from group A showed no response and remained in remission for a mean of 22·9 months after testing. None of the six children in group B responded, and at testing had 17-85% blasts in their bone marrow.During the study no patient relapsed who had not shown a positive response. The technique merits further study as a guide to the presence of leukaemic cells.     

Phospholipid synthesis in aging potato tuber tissue

The effect of activation (“aging”) of potato tuber slices on their phospholipid metabolism was investigated. Aged slices were incubated with ¹⁴C labeled choline, ethanolamine, methionine, serine, and acetate. In all cases, the incorporation of radioactivity into the lipid fraction increased with the length of time the slices were aged. This incorporation was shown to be true synthesis and not exchange between precursors and existing phospholipids.

The increased incorporation of labeled choline into lipids was mainly due to an increase in its uptake by the tissue, the presence of actidione during aging prevented this increased uptake. The increase in the incorporation of labeled acetate into lipids resulted from the development of a fatty acid synthetase during aging. In the case of ethanolamine, both its uptake into the tissue and its incorporation into the lipid fraction increased.

The phospholipids formed from these precursors were identified by paper and thin-layer chromatography. The major compound formed from choline was lecithin, while phosphatidylethanolamine and a small amount of lecithin were formed from ethanolamine.

     

Transport and metabolism of indole-3-acetic Acid in coleus petiole segments of increasing age

Transport and metabolism of IAA-1-¹⁴C in Coleus blumei Benth. was studied by means of a combination of liquid scintillation counting, autoradiography and thin-layer chromatography. Transport of IAA in petiole segments of increasing age (No. 2-8) was strictly polar in a basipetal direction. No acropetal movement occurred in either young or old tissues. The greatest amount, expressed as a percentage of the radioactivity lost from the donor block, was found in basal receivers on petiole number 2. There was gradually less transport in older segments. The recovery as a percentage of the radioactivity not accounted for by donor and receiver blocks, measured by counting the radioactivity in an acetonitrile-extract of petiole segments, was low: 25 to 50%. In this acetonitrile-soluble fraction evidence for different radioactive compounds was found, depending on the age of the tissue. A possible relationship between the amounts of auxin transported in the tissue and its corresponding metabolism is discussed.     

Studies on cytokinin-controlled bud formation in moss protonemata

Application of cytokinins to moss protonemata of the proper physiological age causes bud formation on specific cells (caulonema). During the early stages of their development, buds revert to protonemal filaments if the cytokinin has been removed by washing the protonemata. This indicates that the hormone is not acting as a “trigger” but has to be present during a critical period of time until differentiation is stabilized. Autoradiographs of protonemata treated with a labeled cytokinin, benzyladenine-benzyl-7-¹⁴C, show a striking accumulation of the radioactivity in caulonema cells which are in the stage of bud formation, and in the buds themselves. Cells which did not react to the hormone contained very little radioactivity. The accumulation of benzyladenine in the “target cells” may be due to the presence of binding sites which, in turn, may distinguish responding cells from non-responding ones.     

Triolein-I131 Tolerance in Patients with Coronary Heart Disease

The value of the oral triolein-I¹³¹ “tolerance” test in the study of patients with coronary heart disease was assessed. Thirtynine patients were divided into three groups: those with clinical evidence of coronary heart disease, those with increased risk, and those with no increased risk of coronary heart disease. The variability of the results precluded differentiation between the groups on the basis of this test. A minority of the patients with coronary heart disease showed strikingly elevated blood levels of lipid-bound radioactivity following the oral ingestion of triolein-I¹³¹. It was concluded that this test is of no use in the diagnosis of coronary heart disease but may identify those patients with coronary heart disease who dispose of orally ingested fat in a grossly abnormal fashion.     

Myocardial Infarction and Deep-vein Thrombosis

In a study of 52 patients admitted into the coronary intensive care unit the incidence of deep-vein thrombosis was measured with the ¹²⁵I-fibrinogen test. Of these patients 31 were eventually confirmed to be suffering from acute myocardial infarction. This preliminary study showed that in patients with a confirmed infarct who were not treated with anticoagulants the incidence of deep-vein thrombosis was 38% and in those treated it was 5·5%. In patients who were “severely ill” from whatever the cause there was a high incidence of deep-vein thrombosis (68%).     

Technetium-99m in the Diagnosis of Thyrotoxicosis

The thyroid uptake at 20 minutes of intravenously administered Technetium-99^m (^99mTc) was measured in 117 patients with a standard scintillation counter. Patients were divided into three groups on the basis of clinical assessment, four-hour ¹³¹I uptake, triiodothyronine (T-3) resin uptake, and protein-bound iodine measurements.In 31 patients with no evidence of thyroid disease the mean ^99m Tc uptake was 1·8% ±S.D. 1·1%. In 32 patients with thyroid enlargement who were euthyroid the mean uptake was 2·5% ±S.D. 2·2%. In 54 thyrotoxic patients the mean uptake was 17·7% with a range of 4·1 to 44%, all cases having an uptake above the upper limit of normal (4·0%). These results agree closely with reported uptake studies using scanning techniques. In seven patients the extrathyroidal neck activity was measured by using a scanner, and the mean was 6·3% of the extrathyroidal total body radioactivity comparing favourably with an assumed 6% used in our calculations.We have shown that the measurement of the thyroid uptake of ^99mTc with a scintillation counter is of value, and that it is not necessary to use scanning techniques in the diagnosis of thyrotoxicosis. Advantages of ^99m Tc are minimal radiation, reduction in patient and laboratory time, and low cost.     

Studies of Sulfate Utilization by Algae: 9. Fractionation of a Cell-free System from Chlorella into Two Activities Necessary for the Reduction of Adenosine 3'-Phosphate 5'-Phosphosulfate to Acid-Volatile Radioactivity

Further properties of the enzymatic system obtained from Chlorella pyrenoidosa (Emerson strain 3) which reduces adenosine 3′-phosphate 5′-phosphosulfate-³⁵S to acid-volatile radioactivity, when fortified with Mg²⁺ and 2, 3-dimercaptopropan-1-ol as reductant, are described. Optimal concentrations of adenosine 3′-phosphate 5′-phosphosulfate-³⁵S and Mg²⁺ and the pH optimum have been determined. 2,3-Dimercaptopropan-1-ol can be replaced by dithiothreitol, mercaptoethanol, reduced glutathione, cysteine, and cysteamine. Treatment of the crude extracts with ammonium sulfate and alumina C-gamma gel yields two fractions, designated “S” and “A,” which must be recombined to obtain acid-volatile radioactivity. Further fractionation of fraction S by ammonium sulfate gradient elution and diethylaminoethyl cellulose chromatography yields approximately a 50-fold increase in specific activity compared to that found in the crude extract. This material appears to contain an active component with a molecular weight estimated by agarose gel chromatography of about 330,000.     

Enhancement of CO(2) Uptake in Avena Coleoptiles by Fusicoccin

When Avena coleoptile segments are immersed in a solution containing H¹⁴CO₃⁻, the appearance of label in the tissue is stimulated approximately 3-fold by fusicoccin application. This effect is rapid (1-2 minutes lag time), dependent upon respiratory energy, inhibited by carbonyl cyanide m-chlorophenylhydrazone, but not appreciably altered by cycloheximide treatment. A large percentage of the cellular radioactivity is found in the form of malate. Preliminary experiments indicate that CO₂, as opposed to HCO₃⁻, is the favored species of “CO₂” taken up by the segments. These results are consistent with the notion that CO₂, presumably by virtue of its fixation and conversion to malic acid, participates in the early events associated with fusicoccin-enhanced acidification of the cell wall region leading to the stimulation of cell extension growth.     

Auxin transport in roots

Summary The net uptake and movement of radioactivity by 12-mm root segments of Zea mays have been studied as a function of time at 5, 15 and 25° C. Segments were supplied with an agar donor block containing 1 M IAA-1-¹⁴C or IAA-2-¹⁴C continuously or for a limited period of time (pulse-labelling). In the latter case the original donor block was replaced either by a plain agar block or by one containing 1 M unlabelled IAA. Receiver blocks were placed at the other end of the segments.The net uptake of radioactivity from the donor block at 15° C was greater at the basal end than at the apical end of the segment. At 5 and 15° C, the net uptake from a basal donor was virtually linear with time but at 25° C the rate of net accumulation decreased after about 10 h. Decarboxylation of IAA undoubtedly occurred at 15 and 25° C when the concentration in the tissue attained a high value.An acropetally polarised movement of radioactivity into the receiver blocks occurred regardless of whether the results were based on the actual amounts of radioactivity in the receiver block, or on the amounts in the receiver block expressed as a percentage of the net total radioactivity accumulated from the donor block. Only one radioactive substance was present in the receiver block and it ran to the same R_f as IAA in the isopropanol: ammonium: water solvent system.The amounts of radioactivity moving into that part of the root segment at least 6 mm distant from the end in contact with either an apical or a basal donor block were assessed. An acropetal polarity in the movement of radioactivity was observed on the basis of the actual amounts of radioactivity in these distal parts of the segments, but no such polarity was evident when the amounts of radioactivity were expressed as a percentage of the net total accumulated from the donor block. At least 3 radioactive substances were present in the tissue in addition to the substance running to the same R_f as IAA. The distribution of radioactivity in the segment cannot therefore be used to assess the distribution of IAA.Acropetal movement of radioactivity into an apical receiver block is not dependent upon the continued uptake of IAA at the basal end of the segment. No distinct pulses of radioactivity were detected moving through the root segments.Only a small part of the radioactivity in the root segment appears to be located in the polar transport system, while the bulk is not. The polarity found in the movement of the bulk radioactivity within the segment seems to be related to the polarity in IAA uptake from the donor blocks.     

Dynamics of photoassimilated carbon in douglas fir seedlings

The relations between CO₂ uptake, translocation, and carbon accumulation in several vegetative components of Douglas fir seedlings (Pseudotsuga menziesii [Mirb.] Franco) have been quantified using ¹⁴CO₂. Seedlings were exposed to a constant specific radioactivity of ¹⁴CO₂ and a repeating daily pattern of temperature and light for 4 consecutive days. Results of ¹⁴C analysis, which indicated a transitory pattern of photoassimilated carbon movement, were extrapolated to a “steady rate” using a compartment analysis. Accumulation rates of photoassimilated carbon, relative to tissue carbon, were new needles, 0.94%/day, old needles, 1.14%/day, new shoots 0.38%/day, stem, 0.16%/day, and roots, 0.50%/day. Therefore, the source of carbon, the needles, is also the strongest sink.     

Transport and distribution of homocarnosine after intracerebroventricular and intravenous injection in the rat

Rats were injected intracerebroventricularly (i.c.v.) or i.v. with [¹⁴C]homocarnosine (250 nmol). Distribution of the dipeptide in brain structures, transport from the brain to the blood, distribution in peripheral organs, and excretion in the urine were studied by measuring radioactivity in tissue, plasma, and urine samples by liquid scintillation counting 15–120 min after injection. After i.c.v. injection, [¹⁴C]homocarnosine was taken up into all parts of the brain investigated (highest uptake in structures close to the site of injection), it was transported to the blood, and radioactive substances were found in low concentration in muscle, spleen, and liver, in high concentration in the kidneys, and very high concentration in the urine. Investigations using high pressure liquid chromatography (HPLC) showed that no degradation took place in the brain, all radioactivity was found in the homocarnosine fraction. In the plasma 86% of the radioactivity was found in the GABA fraction presumed to be formed by cleavage of the peptide, while in the kidneys 35% and in the urine 40% was found in the GABA fraction. After i.v. injection of [¹⁴C]homocarnosine, no radioactivity was measured in hippocampus, striatum, cerebellum and cerebral cortex 15 min after injection, however, 60 min after injection a very low activity was detected in these structures (estimated intravascular radioactivity subtracted). A low activity was also measured in the spinal cord both 15 and 60 min after injection. When homocarnosine and GABA were separated on HPLC, all radioactivity in brain tissue was found in the GABA fraction, indicating either that [¹⁴C]homocarnosine did not cross the blood-brain barrier in amounts that could be measured with the method used, or that peptide entering the brain was rapidly transported back to the blood. [¹⁴C]Homocarnosine was not taken up either into crude synaptosomal preparations from hippocampus, striatum, cerebellum, cortex and spinal cord, or into slices prepared from the hippocampus and striatum. Transport from the brain to the kidneys and excretion in the urine seems to be a major route for disposal of this peptide in the rat.     

Bed Rest versus Early Ambulation with Standard Anticoagulation in The Management of Deep Vein Thrombosis: A Meta-Analysis

Introduction

Bed rest has been considered as the cornerstone of management of deep vein thrombosis (DVT) for a long time, though it is not evidence-base, and there is growing evidence favoring early ambulation.

Methods

Electronic databases including Medline, PubMed, Cochrane Library and three Chinese databases were searched with key words of “deep vein thrombosis”, “pulmonary embolism”, “venous thrombosis”, “bed rest”, “immobilization”, “mobilization” and “ambulation”. We considered randomized controlled trials, prospective or retrospective cohort studies that compared the outcomes of acute DVT patients managed with early ambulation versus bed rest, in addition to standard anticoagulation. Meta-analysis pertaining to the incidence of new pulmonary embolism (PE), progression of DVT, and DVT related deaths were conducted, as well as the extent of remission of pain and edema.

Results

13 studies were included with a total of 3269 patients. Compared to bed rest, early ambulation was not associated with a higher incidence of new PE, progression of DVT, or DVT related deaths (RD −0.03, 95% CI −0.05∼ −0.02; Z = 1.24, p = 0.22; random effect model, Tau² = 0.01). Moreover, if the patients suffered moderate or severe pain initially, early ambulation was related to a better outcome, with respect to remission of acute pain in the affected limb (SMD 0.42, 95%CI 0.09∼0.74; Z = 2.52, p = 0.01; random effect model, Tau² = 0.04). Meta-analysis of alleviation of edema cannot elicit a solid conclusion because of significant heterogeneity among the few studies.

Conclusions

Compared to bed rest, early ambulation of acute DVT patients with anticoagulation was not associated with a higher incidence of new PE, progression of DVT, and DVT related deaths. Furthermore, for the patients suffered moderate or severe pain initially, a better outcome can be seen in early ambulation group, regarding to the remission of acute pain in the affected limb.     

“Capillary Permeability” in Patients with Collagen Vascular Diseases

“Capillary permeability” to serum albumin has been measured in patients with collagen vascular diseases by a method which compares the dilution of intravenously injected ¹³¹I-human serum albumin and ⁵¹Cr-R.B.C.s. The results indicate an increased capillary permeability comparable to that which occurs in patients with extensive inflammatory skin disease. We suggest that this increased capillary permeability may be the cause of the episodes of oedema which occur in patients with collagen vascular diseases such as disseminated lupus erythematosus, systemic sclerosis, dermatomyositis, polyarteritis nodosa, and rheumatoid arthritis. “Spontaneous periodic oedema” may be the presenting feature of collagen vascular disease and is due to increased capillary permeability.     

Detection of Vulnerable Atherosclerotic Plaque and Prediction of Thrombosis Events in a Rabbit Model Using 18F-FDG -PET/CT

Background

Detection of vulnerable plaques could be clinically significant in the prevention of cardiovascular events. We aimed to compare Fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) uptake in vulnerable and stable plaques, and investigate the feasibility of predicting thrombosis events using Positron Emission Tomography/Computed Tomography (PET/CT) angiography.

Methods

Atherosclerosis was induced in 23 male New Zealand white rabbits. The rabbits underwent pharmacological triggering to induce thrombosis. A pre-triggered PET/CTA scan and a post-triggered PET/CTA scan were respectively performed. ¹⁸F-FDG uptake by the aorta was expressed as maximal standardized uptake value (SUV_max) and mean SUV (SUV_mean). SUVs were measured on serial 7.5 mm arterial segments.

Results

Thrombosis was identified in 15 of 23 rabbits. The pre-triggered SUV_mean and SUV_max were 0.768±0.111 and 0.804±0.120, respectively, in the arterial segments with stable plaque, and 1.097±0.189 and 1.229±0.290, respectively, in the arterial segments with vulnerable plaque (P<0.001, respectively). The post-triggered SUV_mean and SUV_max were 0.849±0.167 and 0.906±0.191, respectively in the arterial segments without thrombosis, and 1.152±0.258 and 1.294±0.313, respectively in the arterial segments with thrombosis (P<0.001, respectively). The values of SUV_mean in the pre-triggered arterial segments were used to plot a receiver operating characteristic curve (ROC) for predicting thrombosis events. Area under the curve (AUC) was 0.898. Maximal sensitivity and specificity (75.4% and 88.5%, respectively) were obtained when SUV_mean was 0.882.

Conclusions

Vulnerable and stable plaques can be distinguished by quantitative analysis of ¹⁸F-FDG uptake in the arterial segments in this rabbit model. PET/CT may be used for predicting thrombosis events and risk-stratification in patients with atherosclerotic disease.     

Membrane transport of sugars and amino acids in isolated protoplasts

A method has been developed for observing membrane transport in isolated protoplasts. Transport of sugars and amino acids has been studied in protoplasts isolated from the mesophyll of Pisum sativum L. That uptake was not due to passive diffusion through damaged membranes was demonstrated by supplying simultaneously two sugar stereoisomers, the one ³H-labeled and the other ¹⁴C-labeled. The protoplast membranes were sufficiently functional to discriminate strongly between these stereoisomers.

To characterize transport the nonmetabolized glucose analogue 3-O-methyl glucose (MeG) and amino acid analogue α-aminoisobutyric acid (AIB) were employed. When uptake was compared per unit of protein as between leaf strips and protoplasts prepared from the same tissue, it was estimated that the protoplasts had retained approximately 40 to 50% of the uptake ability of the whole cells. Uptake of neither MeG nor AIB by protoplasts was linear with time, but the tendency to flatten was more marked for AIB. Addition of Mg-ATP to buffered medium significantly promoted AIB uptake, an effect not ascribable to either chelation or pH. Transport of both MeG and AIB was markedly pH-dependent, uptake falling with rise in pH.

The stimulatory effect of Mg-ATP and the pH dependence confirm that uptake was not due to a diffusional inward “leak” but involved membrane function.

This work demonstrates the feasibility of using isolated protoplasts for membrane transport studies. The potential advantages of using protoplasts for such studies are pointed out.

     

Fate of adenovirus type 12 genomes in nonpermissive cells

The fate of ³H-thymidine-labeled adenovirus type 12 deoxyribonucleic acid (DNA) was studied in Nil-2 cells of Syrian hamster origin. It was found that a substantial fraction of ³H-adenovirus type 12 DNA became degraded within 24 hr after infection and was released into the culture fluid. After infection of 5-bromodeoxyuridine (BUdR)-prelabeled cells with ³H-adenovirus type 12, viral DNA became readily separable from cellular DNA by equilibrium centrifugation in CsCl. Part of the viral radioactivity was found to shift gradually to the position of cellular DNA as time progressed after infection. When exponentially growing cells were exposed simultaneously to BUdR, 5-fluorodeoxyuridine, and ³H-adenovirus type 12, up to 50% of the viral radioactivity shifted within 24 hr from the density of viral DNA to that of cellular DNA after equilibrium centrifugation in CsCl. Upon denaturation of the cellular DNA, the isotope was preferentially found to be associated with the “heavy” strand which was synthesized after infection. Upon hybridization of the “heavy” and the “light” strands with sonically treated, denatured ³H-adenovirus type 12 DNA, small and nearly equal amounts of counts hybridized with both strands. The number of counts annealed was in a range similar to that of those annealed with the same amount of DNA derived from adenovirus type 12-transformed hamster cells. These results demonstrate that (i) a substantial proportion of the adsorbed virus becomes degraded within 24 hr; (ii) part of the degradation products is reutilized for cellular DNA synthesis; (iii) only a small fraction, mainly fragments, of viral DNA becomes integrated into both the newly synthesized and the parental strands of cellular DNA.     

Immunophenotyping in Myelodysplastic Syndromes Can Add Prognostic Information to Well-Established and New Clinical Scores

Background

myelodysplastic syndromes (MDS) are a heterogeneous group of hematopoietic clonal disorders. So, prognostic variables are important to separate patients with a similar biology and clinical outcome. We compared the importance of risk stratification in primary MDS of IPSS and WPSS with the just described revision of IPSS (IPSS-R), and examined if variables obtained by bone marrow immunophenotyping could add prognostic information to any of the scores.

Methods

In this prospective study of 101 cases of primary MDS we compared the relation of patients’ overall survival with WHO types, IPSS, IPSS-R, WPSS and phenotypic abnormalities of hematopoietic precursors. We examined aberrancies in myelomonocytic precursors and CD34⁺ cells. Patients were censored when receiving chemotherapy or BM transplantation. Survival analysis was made by Cox regressions and stability of the models was examined by bootstrap resampling.

Results

median age: 64 years (15–93). WHO types: 2 cases of 5q- syndrome, 7 of RA, 64 of RCDM and 28 of RAEB. In the univariate Cox analysis, increasing risk category of all scores, degree of anemia, higher percentage of BM blasts, higher number of CD34⁺ cells and their myeloid fractions besides increasing number of phenotypic abnormalities detected were significantly associated with a shorter survival. In the multivariate analysis comparing the three scores, IPSS-R was the only independent risk factor. Comparing WPSS with phenotypic variables (CD34⁺/CD13⁺ cells, CD34⁺/CD13⁻ cells and “total alterations”) the score and “CD34⁺/CD13⁺ cells” remained in the model. When IPSS was tested together with these phenotypic variables, only “CD34⁺/CD13⁺ cells”, and “total alterations” remained in the model. Testing IPSS-R with the phenotypic variables studied, only the score and “CD34⁺/CD13⁺ cells” entered the model.

Conclusions

Immunophenotypic analysis of myelomonocytic progenitors provides additional prognostic information to all clinical scores studied. IPSS-R improved risk stratification in MDS compared to the former scores.