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Multistep pathogenesis of chronic myelomonocytic leukemia in patients. Eur J Haematol 2022; 109:50-57. [PMID: 35299281 PMCID: PMC9310570 DOI: 10.1111/ejh.13768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/09/2022] [Accepted: 03/10/2022] [Indexed: 01/01/2023]
Abstract
Background A multistep pathogenesis of myeloid leukemia including mutations in epigenetic, spliceosome, and signaling genes has been recently demonstrated in a preclinical model but is poorly validated in patients. Methods Clinical, phenotypic, and biologic features were compared between three distinct molecularly defined CMML cohorts including TET2 monomutated patients (T, n = 10), TET2/SRSF2 bimutated patients (TS, n = 19), and patients who had NRAS mutations in addition to TET2/SRSF2 comutations (TSN, n = 14). Results Median survival was 90, 45, and 9 months, respectively (p = .001). Whereas no patient in the T and TS group transformed into acute myeloid leukemia (AML), 6/14 patients in the TSN group had AML at study entry or transformed during follow‐up. Leukocyte counts, blast cell counts, and LDH levels were significantly higher in TSN vs. TS and T, respectively, whereas hemoglobin and platelet values were not significantly different. Increased growth factor‐independent myeloid colony formation was restricted to TSN but not found in T and TS, respectively. The proportion of patients showing in vitro myelomonocytic skewing in T, TS, and TSN was 0%, 56%, and 100%, respectively (p = .010). Conclusion Our results demonstrate that the model of multistep pathogenesis in CMML can be recapitulated in patients regarding clinical, phenotypic, and biologic features.
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Impact of age on the cumulative risk of transformation in patients with chronic myelomonocytic leukaemia. Eur J Haematol 2021; 107:265-274. [PMID: 33998054 PMCID: PMC8480146 DOI: 10.1111/ejh.13647] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 05/02/2021] [Accepted: 05/04/2021] [Indexed: 12/19/2022]
Abstract
In older patients with chronic myelomonocytic leukaemia (CMML) and limited life expectancy due to age and or comorbidities, it is particularly important to consider the risk of transformation for individualised treatment decisions. There is limited information on potential differences between younger and older CMML patients regarding the cumulative risk of transformation as well as haematological, molecular and biologic characteristics. We analysed data from the Austrian Biodatabase for CMML (ABCMML) to compare these parameters in 518 CMML patients. Categorisation of patients into 3 age-related groups: <60 years, 60-79 years and ≥80 years, showed a significantly lower risk of transformation at higher age by competing risk analysis, with a 4-year risk of 39%, 23% and 13%, respectively (P < .0001). The lower probability of transformation was associated with a lower percentage of blast cells in the peripheral blood (PB) of older patients. Furthermore, we provide a simple score based on age, PB blasts and platelet counts that allowed us to define subgroups of CMML patients with a different cumulative transformation risk, including a low-risk group with a transformation risk of only 5%. Our findings may facilitate reasonable treatment decisions in elderly patients with CMML.
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Myelomonocytic skewing in chronic myelomonocytic leukemia: phenotypic, molecular and biologic features and impact on survival. Eur J Haematol 2021; 106:627-633. [PMID: 33432601 PMCID: PMC8554855 DOI: 10.1111/ejh.13577] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 01/07/2021] [Indexed: 01/03/2023]
Abstract
BACKGROUND Myelomonocytic skewing is considered as a key pathophysiologic phenomenon in chronic myelomonocytic leukemia (CMML), but its prevalence and potential correlation with phenotypic, genotypic, and clinical features are poorly defined. METHODS Skewed differentiation toward the myelomonocytic over erythroid commitment as indicated by an inverse ratio of myelomonocytic/erythroid colonies was investigated in 146 patients with CMML by semisolid in vitro cultures. RESULTS There was a high prevalence of myelomonocytic skewing in patients with CMML (120/146, 82%); whereas, this phenomenon was rare in normal individuals (1/98, 1%). Patients with CMML with myelomonocytic skewing had higher white blood cell and peripheral blast cell counts, and lower platelet values. The number of mutations in genes of the epigenetic and/or splicing category was higher in CMML patients with as compared with patients without skewing. Patients with myelomonocytic skewing had more frequently mutations in RASopathy genes and higher growth factor independent myeloid colony formation. Interestingly, the lack of myelomonocytic skewing discriminated patients with CMML with a particularly favorable prognosis (60 vs 19 months, P = .003) and a minimal risk of transformation. CONCLUSION Myelomonocytic skewing as determined by semisolid cultures can discriminate subgroups of patients with CMML with a different phenotype, a different genotype, and a different prognosis.
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Correlation of RAS-Pathway Mutations and Spontaneous Myeloid Colony Growth with Progression and Transformation in Chronic Myelomonocytic Leukemia-A Retrospective Analysis in 337 Patients. Int J Mol Sci 2020; 21:ijms21083025. [PMID: 32344757 PMCID: PMC7215883 DOI: 10.3390/ijms21083025] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 04/19/2020] [Accepted: 04/22/2020] [Indexed: 01/07/2023] Open
Abstract
Although the RAS-pathway has been implicated as an important driver in the pathogenesis of chronic myelomonocytic leukemia (CMML) a comprehensive study including molecular and functional analyses in patients with progression and transformation has not been performed. A close correlation between RASopathy gene mutations and spontaneous in vitro myeloid colony (CFU-GM) growth in CMML has been described. Molecular and/or functional analyses were performed in three cohorts of 337 CMML patients: in patients without (A, n = 236) and with (B, n = 61) progression/transformation during follow-up, and in patients already transformed at the time of sampling (C, n = 40 + 26 who were before in B). The frequencies of RAS-pathway mutations (variant allele frequency ≥ 20%) in cohorts A, B, and C were 30%, 47%, and 71% (p < 0.0001), and of high colony growth (≥20/105 peripheral blood mononuclear cells) 31%, 44%, and 80% (p < 0.0001), respectively. Increases in allele burden of RAS-pathway mutations and in numbers of spontaneously formed CFU-GM before and after transformation could be shown in individual patients. Finally, the presence of mutations in RASopathy genes as well as the presence of high colony growth prior to transformation was significantly associated with an increased risk of acute myeloid leukemia (AML) development. Together, RAS-pathway mutations in CMML correlate with an augmented autonomous expansion of neoplastic precursor cells and indicate an increased risk of AML development which may be relevant for targeted treatment strategies.
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MESH Headings
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Cytogenetic Analysis
- Disease Progression
- Gene Expression Regulation, Leukemic
- Humans
- Leukemia, Myelomonocytic, Chronic/genetics
- Leukemia, Myelomonocytic, Chronic/metabolism
- Leukemia, Myelomonocytic, Chronic/mortality
- Leukemia, Myelomonocytic, Chronic/pathology
- Mutation
- Neoplasm Staging
- Neoplastic Stem Cells/metabolism
- Prognosis
- Retrospective Studies
- Signal Transduction
- ras Proteins/genetics
- ras Proteins/metabolism
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The Austrian biodatabase for chronic myelomonocytic leukemia (ABCMML) : A representative and useful real-life data source for further biomedical research. Wien Klin Wochenschr 2019; 131:410-418. [PMID: 31321531 PMCID: PMC6748886 DOI: 10.1007/s00508-019-1526-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 06/11/2019] [Accepted: 06/18/2019] [Indexed: 12/22/2022]
Abstract
In the Austrian biodatabase for chronic myelomonocytic leukemia (ABCMML) clinicolaboratory real-life data have been captured from 606 CMML patients from 14 different hospitals over the last 30 years. It is the only large biodatabase worldwide in which functional methods such as semisolid in vitro cultures complement modern molecular methods such as next generation sequencing. This provides the possibility to comprehensively study the biology of CMML. The aim of this study was to compare patient characteristics with published CMML cohorts and to validate established prognostic parameters in order to examine if this real-life database can serve as a representative and useful data source for further research. After exclusion of patients in transformation characteristics of 531 patients were compared with published CMML cohorts. Median values for age, leukocytes, hemoglobin, platelets, lactate dehydrogenase (LDH) and circulating blasts were within the ranges of reported CMML series. Established prognostic parameters including leukocytes, hemoglobin, blasts and adverse cytogenetics were able to discriminate patients with different outcome. Myeloproliferative (MP) as compared to myelodysplastic (MD)-CMML patients had higher values for circulating blasts, LDH, RAS-pathway mutations and for spontaneous myelomonocytic colony growth in vitro as well as more often splenomegaly. This study demonstrates that the patient cohort of the ABCMML shares clinicolaboratory characteristics with reported CMML cohorts from other countries and confirms phenotypic and genotypic differences between MP-CMML and MD-CMML. Therefore, results obtained from molecular and biological analyses using material from the national cohort will also be applicable to other CMML series and thus may have a more general significance.
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Is ruxolitinib a potentially useful drug in hematological malignancies with RAS pathway hyperactivation? Haematologica 2019; 101:e492. [PMID: 27903714 DOI: 10.3324/haematol.2016.156448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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[Congestive heart failure: Treatment with ultrafiltration]. Ann Cardiol Angeiol (Paris) 2016; 65:240-244. [PMID: 27344095 DOI: 10.1016/j.ancard.2016.04.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 04/29/2016] [Indexed: 06/06/2023]
Abstract
INTRODUCTION The prevalence rate of congestive heart failure is approximately 2% in high-income countries. The aim of this study was to assess the overall benefit of ultrafiltration therapy in patients with acute or persistent congestive heart failure. METHODS We conducted a health technology assessment following the EUnetHTA guidelines, with systematic literature review from bibliographic medical databases, independent experts and manufacturer interviews. RESULTS Thirteen clinical trials and five meta-analyses were examined. In the most recent one, 608 patients were included, of which 304 received ultrafiltration therapy and 304 received intravenous loop diuretics. Ultrafiltration therapy seems to be more beneficial regarding the fluid removal and the body weight reduction, (mean difference respectively 1.44kg, IC95% [0.29; 2.59], P-value=0.01 and 1.28L [0.43; 2.12], P-value=0.003). No difference has been showed in overall mortality, renal function, hospital readmission or safety. Medico-economic studies are incomplete and contradictory. CONCLUSION Ultrafiltration therapy seems to be effective, most likely for patients ineligible or resistant to intravenous diuretics. But most topics remain uncertain, mainly impact on overall mortality, safety and cost-effectiveness. Given these knowledge-gaps, the generalization of ultrafiltration therapy should be examined cautiously, and conditional upon a large-scale systematic evaluation.
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Chronic myelomonocytic leukemia patients with RAS pathway mutations show high in vitro myeloid colony formation in the absence of exogenous growth factors. Leukemia 2016; 30:2280-2281. [PMID: 27585952 PMCID: PMC5097063 DOI: 10.1038/leu.2016.235] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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In vitroandin vivoeffects of JAK2 inhibition in chronic myelomonocytic leukemia. Eur J Haematol 2016; 97:562-567. [DOI: 10.1111/ejh.12773] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2016] [Indexed: 12/22/2022]
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Quantitative Analysis of Mutant Subclones in Chronic Myeloid Leukemia: Comparison of Different Methodological Approaches. Int J Mol Sci 2016; 17:ijms17050642. [PMID: 27136541 PMCID: PMC4881468 DOI: 10.3390/ijms17050642] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 04/20/2016] [Accepted: 04/25/2016] [Indexed: 12/17/2022] Open
Abstract
Identification and quantitative monitoring of mutant BCR-ABL1 subclones displaying resistance to tyrosine kinase inhibitors (TKIs) have become important tasks in patients with Ph-positive leukemias. Different technologies have been established for patient screening. Various next-generation sequencing (NGS) platforms facilitating sensitive detection and quantitative monitoring of mutations in the ABL1-kinase domain (KD) have been introduced recently, and are expected to become the preferred technology in the future. However, broad clinical implementation of NGS methods has been hampered by the limited accessibility at different centers and the current costs of analysis which may not be regarded as readily affordable for routine diagnostic monitoring. It is therefore of interest to determine whether NGS platforms can be adequately substituted by other methodological approaches. We have tested three different techniques including pyrosequencing, LD (ligation-dependent)-PCR and NGS in a series of peripheral blood specimens from chronic myeloid leukemia (CML) patients carrying single or multiple mutations in the BCR-ABL1 KD. The proliferation kinetics of mutant subclones in serial specimens obtained during the course of TKI-treatment revealed similar profiles via all technical approaches, but individual specimens showed statistically significant differences between NGS and the other methods tested. The observations indicate that different approaches to detection and quantification of mutant subclones may be applicable for the monitoring of clonal kinetics, but careful calibration of each method is required for accurate size assessment of mutant subclones at individual time points.
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cFinder: definition and quantification of multiple haplotypes in a mixed sample. BMC Res Notes 2015; 8:422. [PMID: 26346608 PMCID: PMC4562109 DOI: 10.1186/s13104-015-1382-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 08/24/2015] [Indexed: 11/10/2022] Open
Abstract
Background Next-generation sequencing allows for determining the genetic composition of a mixed sample. For instance, when performing resistance testing for BCR-ABL1 it is necessary to identify clones and define compound mutations; together with an exact quantification this may complement diagnosis and therapy decisions with additional information. Moreover, that applies not only to oncological issues but also determination of viral, bacterial or fungal infection. The efforts to retrieve multiple haplotypes (more than two) and proportion information from data with conventional software are difficult, cumbersome and demand multiple manual steps. Results Therefore, we developed a tool called cFinder that is capable of automatic detection of haplotypes and their accurate quantification within one sample. BCR-ABL1 samples containing multiple clones were used for testing and our cFinder could identify all previously found clones together with their abundance and even refine some results. Additionally, reads were simulated using GemSIM with multiple haplotypes, the detection was very close to linear (R2 = 0.96). Our aim is not to deduce haploblocks over statistics, but to characterize one sample’s composition precisely. As a result the cFinder reports the connections of variants (haplotypes) with their readcount and relative occurrence (percentage). Download is available at http://sourceforge.net/projects/cfinder/. Conclusions Our cFinder is implemented in an efficient algorithm that can be run on a low-performance desktop computer. Furthermore, it considers paired-end information (if available) and is generally open for any current next-generation sequencing technology and alignment strategy. To our knowledge, this is the first software that enables researchers without extensive bioinformatic support to designate multiple haplotypes and how they constitute to a sample. Electronic supplementary material The online version of this article (doi:10.1186/s13104-015-1382-7) contains supplementary material, which is available to authorized users.
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Resonant third harmonic generation of KrF laser in Ar gas. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:123105. [PMID: 25554270 DOI: 10.1063/1.4902346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Investigations of emission of harmonics from argon gas jet irradiated by 700 fs, 5 mJ pulses from a KrF laser are presented. Harmonics conversion was optimized by varying the experimental geometry and the nozzle size. For the collection of the harmonic radiation silicon and solar-blind diamond semiconductor detectors equipped with charge preamplifiers were applied. The possibility of using a single-crystal CVD diamond detector for separate measurement of the 3rd harmonic in the presence of a strong pumping radiation was explored. Our experiments show that the earlier suggested 0.7% conversion efficiency can really be obtained, but only in the case when phase matching is optimized with an elongated gas target length corresponding to the length of coherence.
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Improvement of the spatial and temporal contrast of short-pulse KrF laser beams. EPJ WEB OF CONFERENCES 2013. [DOI: 10.1051/epjconf/20135907006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Endometrial polyps in the bitch: a retrospective study of 21 cases. J Comp Pathol 2013; 149:410-6. [PMID: 23651692 DOI: 10.1016/j.jcpa.2013.03.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 01/28/2013] [Accepted: 03/12/2013] [Indexed: 10/26/2022]
Abstract
Endometrial polyps (EPs) are tumour-like lesions reported frequently in domestic carnivores. The present report describes the clinical and pathological features of EPs in 21 bitches. Most affected bitches had a regular reproductive history. Five bitches had no clinical signs and eleven showed clinical signs of pyometra. Four bitches had a large EP which resulted in compression of the abdominal viscera. One bitch had an acute uterine torsion. A clinical diagnosis of EPs was only made when the lesions were large and identified by abdominal palpation or ultrasound. Grossly, the EPs were 5-25 cm in diameter and were single, sessile or pedunculated. They were often associated with cystic endometrial hyperplasia. Microscopically, the EPs were fibroglandular with the stroma sometimes being haemorrhagic and infiltrated by inflammatory cells. In one case, there were areas of stromal smooth muscle and epithelial squamous metaplasia, which may have been consistent with preneoplastic change.
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Comparison of the sensitivity of manual and automated immunomagnetic separation methods for detection of Shiga toxin-producing Escherichia coli O157:H7 in milk. J Appl Microbiol 2002; 92:1015-20. [PMID: 12010540 DOI: 10.1046/j.1365-2672.2002.01646.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To determine the sensitivity of methods for detection of injured and uninjured Escherichia coli O157:H7 (E. coli O157) in raw and pasteurized milk. METHODS AND RESULTS Raw milk, pasteurized milk with 1.5% fat content and pasteurized milk with 3.5% fat content were spiked with E. coli O157 at low levels. The samples were enriched in modified tryptone soya broth with novobiocin (mTSBn) at 37 degrees C. Aliquots of the enriched culture were analysed either by manual immunomagnetic separation (MIMS) and culturing on sorbitol MacConkey agar with or without cefixime and potassium tellurite (SMACct or SMAC), or by automated immunomagnetic separation and integrated ELISA (EiaFosstrade mark). Uninjured E. coli O157 organisms were detected in milk by both methods at 1 cfu 10 ml-1 sample). Injured organisms were detected at levels of about 4 cfu 10 ml-1 sample. Direct enrichment in mTSBn (22 h incubation) showed better sensitivity for injured cells than enrichment in buffered peptone water (BPW, 22 h incubation), or in a two-step enrichment consisting of BPW (6 h, 37 degrees C) and mTSBn (16 h, 37 degrees C), successively. CONCLUSIONS The methods showed equal sensitivity in that they were both able to detect 1 cfu 10 ml-1 milk sample. Injured organisms can be detected and isolated at a level almost as low as this. A resuscitation step is not recommended for the detection and isolation of injured and non-injured E. coli O157 from milk. SIGNIFICANCE AND IMPACT OF THE STUDY Due to the dilution of contamination in the bulk tank, analysis of milk for the presence of E. coli O157 requires a very sensitive method. Both methods described here are useful for such analysis.
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[Acute myologenous leukemia with skin involvement]. Ann Biol Clin (Paris) 2002; 60:229-31. [PMID: 11937451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Abstract
The ideal ion-milled transmission electron microscope (TEM) sample would contain large, thin areas in selected regions, minimal top and bottom surface amorphization, and minimal preferential etching of adjacent materials. This desire has led to studies of these effects and improvements in designs and techniques for ion mills. Minimizing the incident angle of the ion beam to the surface of the sample has been found to be one of the most effective techniques for fulfilling these requirements. A new generation of ion mills has recently been designed to allow low-angle ion milling for the production of very high quality cross-sectional TEM samples. To take advantage of the low-angle ion milling capabilities and high-powered ion sources in these mills, new sample preparation techniques are required. In this paper, a simple technique of mounting material in a specialized titanium grid for cross-sectional TEM sample preparation is presented. This technique is designed to take full advantage of the powerful capabilities of these new low-angle ion mills.
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Simple method for the preparation of InP based samples for TEM investigation. JOURNAL OF ELECTRON MICROSCOPY TECHNIQUE 1991; 18:325-8. [PMID: 1880605 DOI: 10.1002/jemt.1060180315] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A novel, rapid, and simple method is described for the preparation of InP based samples for investigation by transmission electron microscopy (TEM). The key feature of the technique is Ar+ ion bombardment in an iodine ambient. Cross sectional micrographs of Au/InP samples are shown as an example. The technique developed produces a large area of transparent region.
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Abstract
To evaluate the capacity of different metabolic indices to predict performance in middle distance swimming, 15 competitive swimmers performed a submaximal and a maximal 400 metres freestyle swimming event. Expired gases were collected in Douglas bags immediately after the events for the determination of VO2 max. Arterialized blood samples were collected for the determination of maximal blood lactate concentration and the velocity corresponding to blood lactate concentration of 4 mM. The results demonstrated (means +/- SD): maximal velocity of 1.44 +/- 0.05 m.s-1; velocity at 85 percent of VO2 max of 1.36 +/- 0.04 m.s-1; velocity at 4 mM of 1.32 +/- 0.04 m.s-1; VO2 max of 3.47 +/- 0.5 l.min-1; maximal blood lactate concentration of 11.8 +/- 2.5 mM. Multiple regression analysis relating metabolic indices and maximal velocity demonstrated that only velocity at 85 percent of VO2 max (r2 = 0.81) and velocity at 4 mM (r2 = 0.79) were significant predictors. Thus, 79 percent of the variance in the performance of 400 m freestyle can be accounted for the velocity at 85 percent of VO2 max or the velocity at 4 mM. The success in this event seems to depend on the swimmer's capacity to achieve higher velocities with lower blood lactate levels and/or utilizing a lower percentage of their VO2 max.
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Ion beam induced roughness and its effect in AES depth profiling of multilayer Ni/Cr thin films. SURF INTERFACE ANAL 1988. [DOI: 10.1002/sia.740120215] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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The cavitated structure of sintered platinum black; electron microscopic evidences and some catalytic properties. ACTA ACUST UNITED AC 1981. [DOI: 10.1016/0390-6035(81)90047-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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The transport properties of an inhomogeneous model of amorphous silicon and Germanium films. ACTA ACUST UNITED AC 1975. [DOI: 10.1002/pssa.2210300225] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Condensation and epitaxial growth of evaporated thin films on NaCl covered by an amorphous dielectric intermediate layer. ACTA ACUST UNITED AC 1973. [DOI: 10.1007/bf03158075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Some physical characteristics of influenza virus determined by electronmicroscopy. ACTA MICROBIOLOGICA ACADEMIAE SCIENTIARUM HUNGARICAE 1966; 13:337-348. [PMID: 5982319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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