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Smolka J, Kempná K, Kučera P, Kempný K, Asimakopoulou E, Danihelka P. Setup of a 3D printed wind tunnel: Application for calibrating bi-directional velocity probes used in fire engineering applications. HardwareX 2023; 15:e00440. [PMID: 37396413 PMCID: PMC10314287 DOI: 10.1016/j.ohx.2023.e00440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 05/25/2023] [Accepted: 06/07/2023] [Indexed: 07/04/2023]
Abstract
The research presented here focuses on the development of a 3D printed wind tunnel and the relevant equipment to be used for calibrating bi-directional velocity probes (BDVP). BDVP are equipment to be used for measuring velocity flow by determining the pressure difference of hot gases generated during fires. The manufactured probes require calibration to determine the calibration factor. The calibration is usually performed in wind tunnels which can be difficult to access due to costs, complexity and the various pieces of equipment required. The aim of the current study is to develop and assemble an inexpensive and easy-to-build bench-scale wind tunnel, with a data-logging system and fan control functionalities for fast and effective calibration of BDVP. A 3D printer with a PET-G filament is used, able to produce parts for the wind tunnel system which are durable and easy to handle and assemble. The system additionally includes an Arduino-based measuring unit with a hot-wire anemometer and temperature correction: Rev. P. This takes precise measurements; continuously logging data on a computer through a USB interface and capable of saving data on an SD card. This design provides users with parameters of velocity flow up to 4 m/s with standard deviation of 1.2 % and turbulence intensity of 1 %. The main advantages of this wind tunnel are its simplicity to build and portability.
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Affiliation(s)
- Jan Smolka
- VSB - Technical University of Ostrava, Faculty of Safety Engineering, Lumirova 630/13, Ostrava – Vyskovice 700 30, Czech Republic
| | - Kamila Kempná
- VSB - Technical University of Ostrava, Faculty of Safety Engineering, Lumirova 630/13, Ostrava – Vyskovice 700 30, Czech Republic
| | - Petr Kučera
- VSB - Technical University of Ostrava, Faculty of Safety Engineering, Lumirova 630/13, Ostrava – Vyskovice 700 30, Czech Republic
| | - Kamil Kempný
- Majaczech, z.s., Bile Policany 1, 544 52, Czech Republic
| | - Eleni Asimakopoulou
- University of Central Lancashire, School of Engineering, Fylde Rd, Preston PR1 2HE, UK
| | - Pavel Danihelka
- Occupational Safety Research Institute, Jeruzalemska 1283/9, Praha 1 – Nove Mesto, 110 00, Czech Republic
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Thai T, Kučera P, Bernatik A. Noise Pollution and Its Correlations with Occupational Noise-Induced Hearing Loss in Cement Plants in Vietnam. Int J Environ Res Public Health 2021; 18:ijerph18084229. [PMID: 33923566 PMCID: PMC8073271 DOI: 10.3390/ijerph18084229] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/14/2021] [Accepted: 04/15/2021] [Indexed: 12/20/2022]
Abstract
Noise-Induced Hearing Loss (NIHL) is a global issue that is caused by many factors. The purpose of this study was to survey noise level to identify NIHL and its relationship with other factors in cement plants in Vietnam. Noise level was measured at one cement plant and three cement grinding stations located in the South of Vietnam. The audiometric data of exposed workers were surveyed to determine NIHL. Finally, the relationship between NIHL and noise level in cement plants was determined. The results show that noise level in almost all processes exceeded the permissible exposure limit (PEL). In this study, 42 cases (10% of exposed workers) with occupational NIHL were found with mean age (SD) of 49 (9.0) years. All NIHL cases were found in the departments in which the noise level exceeded the PEL, which included quarry (n = 16), maintenance (n = 12), production (n = 10), co-waste processing (n = 3) and quality assurance (n = 1). There was a positive and significant correlation between the NIHL and the excessive noise exposure in the cement plants (r = 0.89, p = 0.04).
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Affiliation(s)
- Tinh Thai
- Faculty of Safety Engineering, VŠB-Technical University of Ostrava, 70030 Ostrava, Czech Republic;
- Correspondence:
| | - Petr Kučera
- Department of Fire Protection, VŠB-Technical University of Ostrava, 70030 Ostrava, Czech Republic;
| | - Ales Bernatik
- Faculty of Safety Engineering, VŠB-Technical University of Ostrava, 70030 Ostrava, Czech Republic;
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Abstract
In this paper, we investigate CNF encodings, for which unit propagation is strong enough to derive a contradiction if the encoding is not consistent with a partial assignment of the variables (unit refutation complete or URC encoding) or additionally to derive all implied literals if the encoding is consistent with the partial assignment (propagation complete or PC encoding). We prove an exponential separation between the sizes of PC and URC encodings without auxiliary variables and strengthen the known results on their relationship to the PC and URC encodings that can use auxiliary variables. Besides of this, we prove that the sizes of any two irredundant PC formulas representing the same function differ at most by a factor polynomial in the number of the variables and present an example of a function demonstrating that a similar statement is not true for URC formulas. One of the separations above implies that a q-Horn formula may require an exponential number of additional clauses to become a URC formula. On the other hand, for every q-Horn formula, we present a polynomial size URC encoding of the same function using auxiliary variables. This encoding is not q-Horn in general.
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Szász P, Kučera P, Čtvrtlík F, Langová K, Hartmann I, Tüdös Z. Diagnostic Value of Unenhanced CT Attenuation and CT Histogram Analysis in Differential Diagnosis of Adrenal Tumors. Medicina (Kaunas) 2020; 56:medicina56110597. [PMID: 33182333 PMCID: PMC7695290 DOI: 10.3390/medicina56110597] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 11/05/2020] [Accepted: 11/06/2020] [Indexed: 01/13/2023]
Abstract
Background and Objectives: Our aim was to verify the optimal cut-off value for unenhanced CT attenuation and the percentage of negative voxels in the volume CT histogram analysis of adrenal masses. Materials and Methods: We retrospectively analyzed the CT data of patients who underwent an adrenalectomy in the period 2002-2019. In total, 413 adrenalectomies were performed. Out of these, 233 histologically verified masses (123 adenomas, 58 pheochromocytomas, 18 carcinomas, and 34 metastases) fulfilled the inclusion criteria and were selected for analysis. The mean unenhanced attenuation in Hounsfield units (HU) and the percentage of voxels with attenuation less than 0 HU (negative voxels) were measured in each mass. Results: The mean unenhanced attenuation with a cut-off value of 10 HU reached a sensitivity of 59.4% and a specificity of 99.1% for benign adenomas. The mean unenhanced attenuation with a cut-off value of 15 HU reached a sensitivity of 69.1% and a specificity of 98.2%. For the histogram analysis, a cut-off value of 10% of negative pixels reached a sensitivity of 82.9% and a specificity of 98.2%, whereas a cut-off value of 5% of negative pixels reached a sensitivity of 87.8% and a specificity of 75.5%. The percentage of negative voxels reached a slightly better area under the curve (0.919) than unenhanced attenuation (0.908). Conclusion: Mean unenhanced attenuation with a cut-off value of 10 HU represents a simple tool, and the most specific one, to distinguish adrenal adenomas from non-adenomas. CT histogram analysis with cut-off values of 10% of negative voxels improves sensitivity without any loss of specificity.
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Affiliation(s)
- Paulína Szász
- Department of Radiology, University Hospital and Faculty of Medicine and Dentistry, Palacky University, 779 00 Olomouc, Czech Republic; (P.S.); (P.K.); (F.Č.)
| | - Petr Kučera
- Department of Radiology, University Hospital and Faculty of Medicine and Dentistry, Palacky University, 779 00 Olomouc, Czech Republic; (P.S.); (P.K.); (F.Č.)
| | - Filip Čtvrtlík
- Department of Radiology, University Hospital and Faculty of Medicine and Dentistry, Palacky University, 779 00 Olomouc, Czech Republic; (P.S.); (P.K.); (F.Č.)
| | - Kateřina Langová
- Department of Medical Biophysics, Faculty of Medicine and Dentistry, Palacky University, 775 15 Olomouc, Czech Republic;
| | - Igor Hartmann
- Department of Urology, University Hospital and Faculty of Medicine and Dentistry, Palacky University, 779 00 Olomouc, Czech Republic;
| | - Zbyněk Tüdös
- Department of Radiology, University Hospital and Faculty of Medicine and Dentistry, Palacky University, 779 00 Olomouc, Czech Republic; (P.S.); (P.K.); (F.Č.)
- Correspondence: ; Tel.: +420-588-445-995
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Kučera P. Salix appendiculata (Salicaceae) found in the Western Carpathians in Slovakia. Ukr Bot J 2019. [DOI: 10.15407/ukrbotj76.02.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Heneberg P, Šimčíková D, Čecháková M, Rypáčková B, Kučera P, Anděl M. Autoantibodies against ZnT8 are rare in Central-European LADA patients and absent in MODY patients, including those positive for other autoantibodies. J Diabetes Complications 2019; 33:46-52. [PMID: 30377089 DOI: 10.1016/j.jdiacomp.2018.10.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 08/10/2018] [Accepted: 10/07/2018] [Indexed: 12/14/2022]
Abstract
BACKGROUND Testing for autoantibodies against the zinc transporter ZnT8 (ZnTA) is becoming routine in pediatric diabetes. However, available data are inconclusive when focusing on adult-onset diabetes, including autoimmune diabetes, which does not require insulin at diagnosis (LADA). BASIC PROCEDURES We examined the ZnTA prevalence and titers and matched them with the clinical phenotype and PTPN22 genotypes of Czech LADA patients who were positive for GADA and/or IA2A and had a fasting C-peptide level >200 pmol/L at diagnosis as well as HNF4A-, GCK- or HNF1A-MODY patients and healthy controls. MAIN FINDINGS Most LADA patients were negative for ZnTA, and the sensitivity of the assay was only 18-20% for patients with LADA-like progression to insulinotherapy compared to healthy controls. In LADA patients, there was no association between the ZnTA and PTPN22 risk genotypes. LADA patients positive for ZnTA had a lower BMI than those positive for other autoantibodies alone. Importantly, MODY patients were completely negative for ZnTA, and the levels of ZnTA in MODY patients were similar to those in healthy controls. CONCLUSIONS ZnTA quantification did not improve LADA diagnosis. However, positivity for ZnTA can be used as a negative MODY pre-diagnostic criterion even in the region of Central and East Europe, where other islet cell autoantibodies are common in MODY patients.
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Affiliation(s)
- Petr Heneberg
- Charles University, Third Faculty of Medicine, Prague, Czech Republic.
| | - Daniela Šimčíková
- Charles University, Third Faculty of Medicine, Prague, Czech Republic
| | - Marie Čecháková
- Charles University, Third Faculty of Medicine, Prague, Czech Republic
| | - Blanka Rypáčková
- Charles University, Third Faculty of Medicine, Prague, Czech Republic
| | - Petr Kučera
- Charles University, Third Faculty of Medicine, Prague, Czech Republic
| | - Michal Anděl
- Charles University, Third Faculty of Medicine, Prague, Czech Republic
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Heneberg P, Riegerová K, Říhová A, Šimčíková D, Kučera P. Updates on the surface antigens of basophils: CD16 on basophils of patients with respiratory or insect venom allergy and the rejection of CD203c and CD63 externalization decoupling by bisindolylmaleimides. Clin Exp Allergy 2018; 49:54-67. [PMID: 30288810 DOI: 10.1111/cea.13288] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 09/06/2018] [Accepted: 09/28/2018] [Indexed: 12/19/2022]
Abstract
BACKGROUND CD16 was previously suggested to be a new marker of basophils that is subject to downregulation by FcεRI crosslinking. Certain compounds, including supraoptimal concentrations of the PKC inhibitors, bisindolylmaleimides, decouple the release of granules containing CD203c, CD63 and histamine, and may thus help to identify the mechanisms related to the CD16 externalization. OBJECTIVE We hypothesized that CD16 is differentially expressed on the surface of basophils in patients with birch pollen or insect venom allergy and is subject to a regulation in response to allergens. We also employed CD203c and CD63 externalization decoupling by bisindolylmaleimides. METHODS We performed a basophil activation test coupled with CD16 and histamine detection using cells isolated from patients with allergy to birch pollen or insect venom and negative controls. We employed two PKC inhibitors, bisindolylmaleimide II and Ro 31-8220 at their supraoptimal concentrations and, after difficulties reproducing previously published data, we analyzed the fluorescence of these inhibitors alone. We identified the CD16 isoforms by sequencing nested RT-PCR amplicons from flow cytometry sorted basophils and by cleaving the CD16b GPI anchor using a phospholipase C. RESULTS We provide the first evidence that CD16a is expressed as a surface antigen on a small subpopulation of human basophils in patients with respiratory and insect venom allergy, and this antigen shows increased surface expression following allergen challenge or FcεRI crosslinking. We rejected the apparent decoupling of the surface expression of basophil activation markers following the administration of bisindolylmaleimides. CONCLUSIONS & CLINICAL RELEVANCE The inclusion of αCD16 in negative selection cocktails selects against a subset of basophils that are CD16+ or CD16dim . Using CD16dim basophils and unstained leucocytes, we show that previous studies with supraoptimal concentrations of bisindolylmaleimides are likely flawed and are not associated with the differential expression of CD203c and CD63.
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Affiliation(s)
- Petr Heneberg
- 2nd Department of Internal Medicine, Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Kamila Riegerová
- Department of Immunology, Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Adéla Říhová
- Department of Immunology, Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Daniela Šimčíková
- 2nd Department of Internal Medicine, Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Petr Kučera
- Department of Immunology, Third Faculty of Medicine, Charles University, Prague, Czech Republic
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Šálková D, Kučera P, Moravec L. Effect of Introducing Second Reduced Rate of VAT on Consumer Purchase Behaviour with Gluten-free Food. Acta Univ Agric Silvic Mendelianae Brun 2017. [DOI: 10.11118/actaun201765031045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Savický P, Kučera P. Generating Models of a Matched Formula With a Polynomial Delay. J ARTIF INTELL RES 2016. [DOI: 10.1613/jair.4989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
A matched formula is a CNF formula whose incidence graph admits a matching which matches a distinct variable to every clause. Such a formula is always satisfiable. Matched formulas are used, for example, in the area of parametrized complexity. We prove that the problem of counting the number of the models (satisfying assignments) of a matched formula is #P-complete. On the other hand, we define a class of formulas generalizing the matched formulas and prove that for a formula in this class one can choose in polynomial time a variable suitable for splitting the tree for the search of the models of the formula. As a consequence, the models of a formula from this class, in particular of any matched formula, can be generated sequentially with a delay polynomial in the size of the input. On the other hand, we prove that this task cannot be performed efficiently for linearly satisfiable formulas, which is a generalization of matched formulas containing the class considered above.
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Heneberg P, Riegerová K, Kučera P. Pimecrolimus Is a Potent Inhibitor of Allergic Reactions to Hymenopteran Venom Extracts and Birch Pollen Allergen In Vitro. PLoS One 2015; 10:e0142953. [PMID: 26562153 PMCID: PMC4643035 DOI: 10.1371/journal.pone.0142953] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 10/28/2015] [Indexed: 01/16/2023] Open
Abstract
Pimecrolimus (Elidel, SDZ ASM 981) is an anti-inflammatory and immunomodulatory 33-epichloro-derivative of macrolactam ascomycin, with low potential for affecting systemic immune responses compared with other calcineurin inhibitors, cyclosporin A and tacrolimus. Despite numerous studies focused on the mechanism of pimecrolimus action on mast cells, only the single report has addressed pimecrolimus effects on other typical FcεRI-expressing cells, the basophils. Patients allergic to birch pollen (n = 20), hymenopteran venoms (n = 23) and 10 non-allergic volunteers were examined. Primary human basophils pre-treated or not with 0.5-50 μMol pimecrolimus were exposed to various concentrations of recombinant Bet v 1a allergen, bee or wasp venom extracts and anti-IgE for 20 min, and then examined for the expression of CD45, CD193, CD203c, CD63 and CD164 using flow cytometry. The externalization of basophil activation markers (CD63 and CD164) was equally inhibited through pimecrolimus in cells activated by recombinant pollen allergen, hymenopteran venom extracts and anti-IgE. Although the individual response rate was subject to strong variation, importantly, pre-treatment with pimecrolimus lowered the number of activated basophils in response to any of the stimuli in the basophils from all patients. The inhibition was concentration-dependent; approximately half of the basophils were inhibited in the presence of 2.5 mMol pimecrolimus. Pimecrolimus is a valuable new tool for the inhibition of hyper-reactive basophils in patients with pollen allergy and a history of anaphylactic reactions to bee or wasp venoms. Further research should address short-term use of pimecrolimus in vivo in a wide spectrum of allergic diseases.
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Affiliation(s)
- Petr Heneberg
- 2nd Department of Internal Medicine, Third Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
- * E-mail:
| | - Kamila Riegerová
- Department of Immunology, Third Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
| | - Petr Kučera
- Department of Immunology, Third Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
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Kučera P, Novák J, Löw J, Dohnal T. Historical Landscape Structures and Their Importance for Landscape Character. Acta Univ Agric Silvic Mendelianae Brun 2015. [DOI: 10.11118/actaun201563010049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Urbanová J, Rypáčková B, Procházková Z, Kučera P, Cerná M, Anděl M, Heneberg P. Positivity for islet cell autoantibodies in patients with monogenic diabetes is associated with later diabetes onset and higher HbA1c level. Diabet Med 2014; 31:466-71. [PMID: 24102923 DOI: 10.1111/dme.12314] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 07/03/2013] [Accepted: 09/04/2013] [Indexed: 11/28/2022]
Abstract
AIMS Islet cell autoantibodies are associated with autoimmune insulitis and belong to the diagnostic criteria of type 1 diabetes mellitus. However, growing evidence suggests that autoantibodies are present in other types of diabetes. Here, we focus on the autoantibody incidence in Czech patients with maturity-onset diabetes of the young and analyse their functional relevance in terms of diabetes onset and control. METHODS Autoantibodies against glutamic acid decarboxylase (GAD) 65 and protein tyrosine phosphatase islet antigen 2 (IA-2) were measured in a cohort of 28 Czech patients with maturity-onset diabetes of the young, all confirmed by genetic testing. Selected clinical data were correlated to the status and kinetics of autoantibodies. RESULTS One quarter of patients with maturity-onset diabetes of the young examined (7/28; 25%) was positive for GAD or IA-2 autoantibodies. GAD autoantibodies were more prevalent (7/7) than IA-2 autoantibodies (1/7). The incidence of autoantibodies did not correlate with human leukocyte antigen status. The patients who were positive for the autoantibodies developed diabetes later than those who were autoantibody-negative, but had worse glycaemic control (increased HbA1c ). Expression of autoantibodies decreased with any improvement of diabetes compensation. Only one patient did not correspond to the above and displayed signs of combined signs of maturity-onset diabetes of the young and Type 1 diabetes. CONCLUSIONS The data suggest transient but highly prevalent islet cell autoantibody expression in Czech patients with maturity-onset diabetes of the young. The autoantibodies were found in patients with delayed diabetes onset, and in times of insufficient diabetes control. As improvement of glycaemic control was associated with a decrease in levels of autoantibodies, their presence may reflect the kinetics of β-cell destruction induced by causes other than autoimmune ones.
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Affiliation(s)
- J Urbanová
- Charles University in Prague, Third Faculty of Medicine, Prague, Czech Republic
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Kučera P, Krejčí I. Contribution of simple heuristics for the vehicle routing problem - A case study of a small brewery. Acta Univ Agric Silvic Mendelianae Brun 2013. [DOI: 10.11118/actaun201361072393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Urbanová J, Rypáčková B, Kučera P, Anděl M, Heneberg P. Should the Negativity for Islet Cell Autoantibodies Be Used in a Prescreening for Genetic Testing in Maturity-Onset Diabetes of the Young? The Case of Autoimmunity-Associated Destruction of Pancreatic β-Cells in a Family of HNF1A-MODY Subjects. Int Arch Allergy Immunol 2013; 161:279-84. [DOI: 10.1159/000346906] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Accepted: 01/02/2013] [Indexed: 11/19/2022] Open
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Vávrová J, Maisnar V, Tichý M, Friedecký B, Čermáková Z, Dastych M, Gottwaldová J, Kučera P, Krotká J, Racek J, Ženková J, Schneiderka P, Lochman P, Zima T, Benáková H, Büchler T, Spáčilová J, Hájek R, Palička V. Interlaboratory study of free monoclonal immunoglobulin light chain quantification. Clin Chem Lab Med 2010; 49:89-92. [PMID: 21034251 DOI: 10.1515/cclm.2011.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Quantification of monoclonal immunoglobulin free light chains (FLCs) in serum is used increasingly in clinical practice for the diagnosis, prognostic assessment, and treatment monitoring of monoclonal gammopathies. It is used as an adjunct to standard serum protein electrophoresis and immunofixation. However, methods for FLC quantification need further standardization and validation. METHODS The Czech Myeloma Group and the Czech Society of Clinical Biochemistry have initiated an interlaboratory study where six laboratories collaborating with the primary myeloma treatment centres measured FLC concentrations in 12 serum samples from patients with monoclonal gammopathies. RESULTS Repeatability of the measurements in five laboratories was calculated based on differences between the results of duplicate measurements. We found that repeatability depended more on the laboratory than on the device used for measurement. CONCLUSIONS The study revealed several weak points in the methodology, including the need for a uniform sample dilution procedure. Interlaboratory reproducibility was comparable with values achieved in the NEQAS programme. Because the κ/λ ratio cannot be measured with high precision, κ and λ FLC concentrations should be used where possible. Due to its impact on the clinical management of patients with gammopathy, FLC quantification needs to become a part of the regular quality control cycle in myeloma centres.
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Affiliation(s)
- Jaroslava Vávrová
- Institute of Clinical Biochemistry and Diagnostics, Charles University Hospital, Hradec Kralove, Czech Republic
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Skalská S, Kučera P, Goldenberg Z, Štefek M, Kyselová Z, Jariabka P, Gajdošíková A, Klobučníková K, Traubner P, Štolc S. Neuropathy in a rat model of mild diabetes induced by multiple low doses of streptozotocin: effects of the antioxidant stobadine in comparison with a high-dose α-lipoic acid treatment. Gen Physiol Biophys 2010. [DOI: 10.4149/gpb_2010_01_50] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Altannavch TS, Roubalová K, Kučera P, Anděl M. Effect of High Glucose Concentrations on Expression of ELAM 1, VCAM-1 and ICAM-1 in HUVEC with and without Cytokine Activation. Physiol Res 2004. [DOI: 10.33549/physiolres.930343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Diabetes mellitus is associated with an increased prevalence of endothelial dysfunction and development of atherosclerotic vascular diseases. We demonstrate here that hyperglycemia results in the expression of adhesion molecules on endothelial cells in vitro. Incubation of human umbilical vein endothelial cells (HUVEC) in a culture medium with 11.0 mM, 16.5 mM and 22.0 mM glucose concentrations induced the expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and endothelial-leukocyte adhesion molecule-1 (ELAM-1). This effect was detectable after 24 h incubation of HUVEC with a high glucose concentration. The effect of high glucose concentration on TNF-alpha induced expression of ELAM-1, VCAM-1 and ICAM-1 was negligible, if at all. These results show that even a short-term exposure of endothelial cells (ECs) to high glucose concentration leads to their activation associated with increased expression of adhesion molecules such as ELAM-1, VCAM-1 and ICAM-1.
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Matějková-Běhanová M, Vaňková M, Hill M, Kučera P, Cinek O, Anděl M, Bendlová B. Polymorphism of INS VNTR is associated with glutamic acid decarboxylase antibodies and postprandial C-peptide in patients with diabetes onset after 35 years of age. Physiol Res 2004. [DOI: 10.33549/physiolres.930431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Variability in the number of tandem repeats of the insulin gene (INS VNTR) is probably involved in the genetic regulation of insulin secretion. The aim of this study was to investigate the association of INS VNTR polymorphism with the presence of glutamic acid decarboxylase antibodies (GADA) and C-peptide levels in patients with the onset of diabetes after 35 years of age. We investigated 117 patients, median of age 63 (range 40-83) years, median of diabetes duration 8 (range 1-30) years; 31 GADA-positive and 86 GADA-negative subjects. INS VNTR polymorphism was typed indirectly using - 23HphI (T/A) polymorphism, which is in complete linkage disequilibrium with INS VNTR. The I/I, I/III and III/III genotypes were found in 22 (71 %), 8 (26 %), 1 (3 %) GADA-positive individuals and in 39 (45 %), 35 (41 %), 12 (14 %) GADA-negative individuals, respectively. The Class I allele and the genotype I/I were significantly associated with the presence of GADA (OR=2.72, CI 95 %=1.29-5.73 and OR=2.95, CI 95 %=1.22-7.13). The presence of Class III allele was significantly associated with a higher level of postprandial C-peptide in GADA-positive subjects, even when regarding the duration of diabetes. Our results of INS VNTR polymorphism in patients with the onset of diabetes after 35 years of age confirm the association of Class I INS VNTR with autoimmune diabetes and the protective effect of Class III INS VNTR on the insulin secretion in GADA-positive subjects.
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Abstract
Extended Leveque problem is studied for linear velocity profiles, vx(z) = u + qz. The existing analytic solution is reconsidered and shown to be inapplicable for the accurate calculation of mean mass-transfer coefficients. A numerical solution is reported and its accuracy is checked in detail. Simple but fairly accurate empirical formulas are suggested for the calculating of local and mean mass-transfer coefficients.
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