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Grohmann M, Hermann I, Hampel M, Karas M, Kalbacher H, Jäck HM, Mielenz D. Tfg (Trk fused gene) is a Carma-1/IKKγ interacting protein involved in CD40-induced canonical NF-κB signaling. Cell Commun Signal 2009. [PMCID: PMC4291726 DOI: 10.1186/1478-811x-7-s1-a4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Vokurka S, Steinerova K, Karas M, Koza V. Characteristics and risk factors of oral mucositis after allogeneic stem cell transplantation with FLU/MEL conditioning regimen in context with BU/CY2. Bone Marrow Transplant 2009; 44:601-5. [DOI: 10.1038/bmt.2009.66] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Benedikt A, Baltruschat S, Arrey TN, Meyer B, Karas M, Bursen A, Dingermann T, Marschalek R. The human AF4 and AF4·MLL multiprotein complexes provide functions in transcription and epigenetic processes. KLINISCHE PADIATRIE 2009. [DOI: 10.1055/s-0029-1222624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Haber J, Rácil Z, Mayer J, Mallátová N, Kouba M, Sedlácek P, Faber E, Herold I, Múdry P, Drgona L, Kocmanová I, Karas M, Buchta V, Vydra J, Kolár M, Trupl J, Maresová V, Rozsypal H, Nýc O, Cwiertka K. [Treatment of invasive candidiasis--recommendations of professional]. VNITRNI LEKARSTVI 2008; 54:1174-1184. [PMID: 19140527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
National working group representing clinicians (hematologists, oncologists, infection diseases and ICU specialists), microbiologists, and different special medical societies and working groups prepared evidence-based guidelines for the treatment established fungal infection--invasive candidiasis in the adult hematology and ICU patients. These guidelines updated those published in the Czech Republic in 2003-2004. Evidence criteria of the Infectious Diseases Society of America (IDSA) were used for assessing the quality of clinical trials, and EORTC/MSG Consensus Group for definitions of invasive fungal disease.
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Rácil Z, Mayer J, Kocmanová I, Haber J, Mallátová N, Kouba M, Sedlácek P, Faber E, Herold I, Múdry P, Drgona L, Karas M, Buchta V, Vydra J, Kolár M, Trupl J, Maresová V, Rozsypal H, Nýc O, Cwiertka K. [Treatment for invasiveness aspergillosis--recommendations of professionals]. VNITRNI LEKARSTVI 2008; 54:1187-1194. [PMID: 19140528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
An increasing incidence of invasive aspergillosis is observed in most immunocompromised patients, and especially patients with acute leukemia and after hematopoietic stem cell transplantation. In order to decrease the mortality due to this infection, the clinicians need to optimise their treatment choice. The objective of these guidelines is to summarize the current evidence for treatment of invasive aspergillosis. The recommendations have been developed by an expert panel following an evidence-based search of literature with regard to current recommendation of European Conference in Infections in Leukemia and Infectious Diseases Society of America.
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Weidlich M, Klammt C, Bernhard F, Karas M, Stein T. Differential activity profiles of translation inhibitors in whole-cell and cell-free approaches. Lett Appl Microbiol 2007; 46:155-9. [DOI: 10.1111/j.1472-765x.2007.02281.x] [Citation(s) in RCA: 1] [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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32
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Eisenhut M, Mißfeldt M, Lehmann WD, Karas M. Synthesis of a bis(aminoethanethiol) ligand with an activated ester group for protein conjugation and 99mTc labeling. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.2580291204] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Schulz E, Karas M, Rosu F, Gabelica V. Influence of the matrix on analyte fragmentation in atmospheric pressure MALDI. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2006; 17:1005-1013. [PMID: 16713286 DOI: 10.1016/j.jasms.2006.03.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Revised: 03/02/2006] [Accepted: 03/18/2006] [Indexed: 05/09/2023]
Abstract
In this paper, we report the measurement of the degree of analyte fragmentation in AP-MALDI as a function of the matrix and of the laser fluence. The analytes include p-OCH3-benzylpyridinium, three peptides containing the sequence EEPP (which cleave very efficiently at the E-P site), and three deoxynucleosides (dA, dG, and dC), which lose the neutral sugar to give the protonated base. We found that the matrix hardness/softness was consistent when comparing the analytes, with a consensus ranking from hardest to softest: CHCA >> DHB > SA approximately THAP > ATT > HPA. However, the exact ranking can be fluence-dependent, for example between ATT and HPA. Our goal here was to provide the scientific community with a detailed dataset that can be used to compare with theoretical predictions. We tried to correlate the consensus ranking with different matrix properties: sublimation or decomposition temperature (determined using thermogravimetry), analyte initial velocity, and matrix proton affinity. The best correlation was found with the matrix proton affinity.
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Brdicka R, Beránek M, Cimburová M, Dvorácková J, Dvoráková D, Hájková J, Haskovec C, Kebrdlová V, Karas M, Kratochvílová A, Losan F, Macek M, Musil F, Putzová M, Rozmanová S, Riedlová P, Safrová M, Scheinost O, Stolba P, Trka J, Vanecek T, Vrtel R. [Frequency view on genome changes testing]. CASOPIS LEKARU CESKYCH 2006; 145:98-103. [PMID: 16521397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Laboratories dealing with human genome, both inherited and acquired changes, dispose with similar methods and technology. The spectrum of genetic tests is relatively broad and the number of mutations or variants tested differs substantially. Also the number of examinations carried out in individual laboratories varies. Data presented in the tables come from the year 2004 and indicate the number of examinations requested and number of positive results. Many laboratories mentioned in the registry CZDDNAL (http://www.uhkt.cz/lab_a_vysetreni/nr lab_dna_diag/dna_lab_db) perform the same tests but there is also a great number of tests carried out by only one laboratory. Reasons of the request, cost-effectiveness and clinical utility of genetic testing is being discussed.
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Petri J, Kaunzinger A, Niemöller A, Karas M. Quality control of tablets by Near Infrared (NIR)-Spectroscopy. DIE PHARMAZIE 2005; 60:743-6. [PMID: 16259120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Today, NIR-spectroscopy is an established analytical technique not only in the identification of raw materials but also in the quantification of active ingredients in tablets. In this work calibration models were set up with tablets of the same active ingredient but of miscellaneous origin and manufacturess. Consequently the tablets had different excipients and appearance. The pharmaceutical preparations used included atenolol 100 mg tablets, enalapril 20 mg tablets and acetylsalicylic acid (ASS) tablets of different dosage units. In order to proof if the calibration models set up are generally feasible the assay declared by the manufacturer was used to calculate the partial least square (PLS) calibration. With respect to enalapril tablets simultaneous analysis by HPLC, according to USP 26 was carried out. It was investigated if such methods allow a determination of active ingredients in tablets within limits of +/- 10% of declaration. It was shown that it is possible to set up calibration models to quantify active ingredients in tablets independent of adjuvants or optical appearance. Additionally it could be shown that NIR-spectroscopy is also applicable to determine the concentration of active ingredients in blister-packed tablets.
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Tsirogianni E, Aivaliotis M, Papasotiriou DG, Karas M, Tsiotis G. Identification of inducible protein complexes in the phenol degrader Pseudomonas sp. strain phDV1 by blue native gel electrophoresis and mass spectrometry. Amino Acids 2005; 30:63-72. [PMID: 16003498 DOI: 10.1007/s00726-005-0219-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2005] [Accepted: 05/18/2005] [Indexed: 10/25/2022]
Abstract
Pseudomonas sp. strain phDV1, being a phenol degrading bacterium, has been found to utilize phenol as sole carbon source via the meta pathway. Blue native polyacrylamide gel electrophoresis (BN-PAGE) is widely used for the analysis of oligomeric state and molecular mass non-dissociated protein complexes. In this study, a number of proteomic techniques were used to investigate the oligomeric state enzymes involved in the aromatic degradation pathway. In particular, the Pseudomonas sp. strain phDV1 proteome was monitored under two different growth substrate conditions, using glucose or phenol as sole carbon source. The protein complexes map was compared by BN-PAGE after fractionation by sucrose density centrifugation of the cell extracts. Multiple differences were detected. Further, analysis and identification of the subunit composition of these complexes was carried out using MALDI-TOF MS, allowing the identification of 49 proteins. Additionally, functional information regarding protein-protein interactions was assembled, by coupling 2-D BN-PAGE with MALDI-TOF MS. Application of this functional proteomics method resulted in an higher number of the identified proteins.
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Chernushevich IV, Bahr U, Karas M. Nanospray 'taxation' and how to avoid it. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2004; 18:2479-2485. [PMID: 15384129 DOI: 10.1002/rcm.1649] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In mass spectrometric analysis with nanospray ionization, some analytes were found to appear in spectra with a delay of tens of minutes, while a few others could not be detected at all. The effect was found to be related to cation-exchange chromatography with negative charge on the glass surface, and with the most affected peptide or protein ions having strong localization of positive charge in blocks of two or more adjacent basic amino acid residues (e.g. melittin). The 'affinity' to the glass surface was studied with a peptide mixture and bovine serum albumin (BSA) tryptic digest solutions at sub-micromolar concentration. About 20% fewer tryptic peptides could be identified from spectra recorded with a glass nanospray capillary compared to those acquired with either conventional 1 microL/min electrospray or a quartz nanospray capillary. Protein identification studies are not likely to be seriously affected by this loss, but other protein applications, such as investigations of mutations or post-translational modifications, may suffer due to reduced sequence coverage. Ways to avoid losses of useful ions are discussed.
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Jindra P, Koza V, Boudová L, Vozobulová V, Cerná K, Karas M, Lysák D, Svojgrová M. Epstein-Barr virus-associated B-cell lymphoproliferative disorder in CLL patients after treatment with fludarabine and cyclophosphamide followed by high-dose chemotherapy with autologous stem cell transplantation. Bone Marrow Transplant 2003; 31:951-2. [PMID: 12748677 DOI: 10.1038/sj.bmt.1704026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Rozman P, Karas M, Kosir A, Labar B, Madrigal A, Middleton D, Navarrete C, Oudshoorn M, Schennach H, Vitek A, Bohinjec M. Are human platelet alloantigens (HPA) minor transplantation antigens in clinical bone marrow transplantation? Bone Marrow Transplant 2003; 31:497-506. [PMID: 12665847 DOI: 10.1038/sj.bmt.1703854] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The role of human platelet alloantigens (HPA) in clinical bone marrow allotransplantation was investigated. The leading hypothesis was that HPA alloepitopes act as minor histocompatibility antigens and aggravate graft-versus-host disease (GVHD). To exclude the effect of MHC disparity, only HLA identical donor-recipient pairs were entered into the study. The influence of HPA compatibility on overall survival, occurrence of relapses and haematopoietic recovery was also investigated. A total of 223 patients who received a graft from an HLA-identical sibling, genotyped for HPA -1, -2, -3, -4 and -5, were observed over a post-transplant period of 24 months following the protocol recommended by EBMT. The data from patients having received grafts from HPA compatible donors were compared to data from patients having received grafts that were mismatched in HPA allotypes in the GVH direction. Analysis of the incidence of acute and chronic (GVHD), overall survival, relapse incidence, haematopoietic recovery and some other clinical parameters did not reveal any significant difference between the HPA-matched and -mismatched groups of patients, regardless of their age. Our results give no evidence that HPA-1, -2, -3 and -5 alloantigens should be considered minor transplantation antigens in clinical bone marrow transplantation.
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Pfenninger A, Karas M, Finke B, Stahl B, Sawatzki G. Mass spectrometric investigations of human milk oligosaccharides. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2002; 501:279-84. [PMID: 11787691 DOI: 10.1007/978-1-4615-1371-1_35] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Human milk oligosaccharides (OS) have been fractionated by gel permeation chromatography (GPC) and analyzed by mass spectrometry (MS). Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF/MS) and electrospray ionization (ESI) ion trap/MS were used. Using a large human milk pool, the MALDI-TOF/MS analysis of high-molecular-mass GPC fractions showed that complex, multiply fucosylated and/or sialylated OS are present over a larger mass range than described previously Acidic oligosaccharides could be detected from low-retention-time GPC fractions with masses up to 4000 Da, which has not been reported before.
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Spengler B, Karas M, Bahr U, Hillenkamp F. Excimer laser desorption mass spectrometry of biomolecules at 248 and 193 nm. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100310a016] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Krüger R, Pfenninger A, Fournier I, Gluckmann M, Karas M. Analyte incorporation and ionization in matrix-assisted laser desorption/ionization visualized by pH indicator molecular probes. Anal Chem 2001; 73:5812-21. [PMID: 11791549 DOI: 10.1021/ac010827r] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Despite the spreading applications of matrix-assisted laser desorption/ionization (MALDI), its fundamental understanding is still limited and under constant debate. This report focuses on the initial state of the analyte in the host matrix. pH indicator dyes serve as molecular probes since their color directly indicates their (de)protonation state. For a set of matrixes at their intrinsic pH, solution color was maintained, delivering clear proof for analyte incorporation in the solution charge state. Moreover, substantial solvent inclusion is determined by 1H NMR spectroscopy. MALDI mass spectra show a clear correlation to the dye charge state. However, the dominant solution species are not observed exclusively in the mass spectra, pointing to a proton transfer or proton neutralization activity of the matrix.
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Schmidt A, Bahr U, Karas M. Influence of pressure in the first pumping stage on analyte desolvation and fragmentation in nano-ESI MS. Anal Chem 2001; 73:6040-6. [PMID: 11791577 DOI: 10.1021/ac010451h] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In ESI MS, some classes of biomolecules are detected only with low signal intensities due to difficulties in achieving efficient analyte desolvation, either because an analyte tends to fragment already at gentle desolvation conditions (i.e., noncovalent protein complexes or nucleotides) or because an analyte requires very strong activation in order to remove solvent molecules (i.e., carbohydrates). Even though the pressure in the first pumping stage of the ESI instrument is known to have an influence on the desolvation conditions, it has never been the focus of a detailed investigation. The role of the pressure in the first pumping stage is systematically interrogated in this study for several model substances. Ion signal intensities and signal-to-noise ratios are significiantly enhanced if the pressure in the first pumping stage is increased and adjusted, and analyte fragmentation can be substantially reduced. Thus, besides thermal heating and the acceleration in the nozzle-skimmer region, which are usually optimized, the pressure in the first pumping stage is an additional important desolvation parameter.
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Schmidt A, Karas M. The influence of electrostatic interactions on the detection of heme-globin complexes in ESI-MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2001; 12:1092-1098. [PMID: 11605970 DOI: 10.1016/s1044-0305(01)00294-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The heme-globin complexes of hemoglobin and myoglobin are investigated in positive-ion mode and negative-ion mode using a nano-ESI source coupled to a quadrupole ion trap MS and an orthogonal time-of-flight MS. The extent of dissociation of these noncovalent complexes upon collisional activation and thus their gas-phase stability is strongly dependent on the polarity of the ESI-MS experiment as well as on the charge of the prosthetic group (ferri-heme [Fe3+-heme]+ vs. ferro-heme [Fe2+-heme]+/-0). The results clearly point to the important role of electrostatic interactions on the gas phase stability of noncovalent complexes and therefore the ion signals observed in ESI-MS experiments.
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Tawab MA, Kaunzinger A, Bahr U, Karas M, Wurglics M, Schubert-Zsilavecz M. Development of a high-performance liquid chromatographic method for the determination of 11-keto-beta-boswellic acid in human plasma. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 761:221-7. [PMID: 11587352 DOI: 10.1016/s0378-4347(01)00335-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A validated HPLC method for the determination of 11-keto-beta-boswellic acid (KBA) in human plasma was developed. The method involves the solid-phase extraction of KBA from plasma followed by a separation with reversed-phase HPLC. Calibration was based on external standardisation and ranged between 0.1 and 2.0 microg KBA per ml plasma. Linearity was established over the entire calibration range and in each case the coefficient of correlation (r2) was above 0.99. The recovery of KBA from plasma was 85.7%. It was further demonstrated that the method can be applied successfully to monitor the level of KBA in plasma.
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Karas M, Cerná K, Koza V, Jindra P, Vozobulová V, Schützová M. [Allogenic transplantation of bone marrow in patients with chronic myeloid leukemia 1991-1995 and 1996-1998. Experience at the Hematology-Oncology Clinic of the University Hospital in Plzen]. VNITRNI LEKARSTVI 2001; 47 Suppl 1:34-9. [PMID: 11693060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
The authors compare the results of allogenic bone marrow transplantations of relatives in patients with chronic myeloid leukaemia during the initial years of the transplantation programme 1991-1995 (group 1, 15 patients) with results achieved in 1996-1998 (group 2, 30 patients) and evaluate the effect of changes concerning supportive treatment and new diagnostic methods. The age median of group 1 was 35 years, the median age of group 2 46 years. In other parameters the groups were comparable. In 1991-1995 a high transplantation mortality by the 100th day was recorded (40% as compared with 17%) and a higher incidence of stage III and IV of the acute reaction of the graft against the host (GVHD) in group 1 (20% vs. 6%). In group 2 there was a higher transplantation mortality after day 100 associated with a more frequent chronic GVHD (0% vs. 16.5%). The total survival is insignificantly better in group 2 (60% in group 1 survive with a median of 58 months follow up and 67% of group 2 with a median follow up of 33 months). Group 2 comprises however older patients. In the improved early transplantation mortality participated new methods, a change of the posttransplantation immunosuppression, experience with care of transplanted patients and better collaboration with other medical disciplines. The authors did not observe a substantial effect of changes in the basic supportive treatment on results of transplantation. Late transplantation mortality associated in particular with a higher incidence of chronic GVHD could be in the authors' opinion reduced by longer administration of immunosuppression after transplantation, in particular in older patients.
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Karas M, Chakrabarti SK. Caffeine potentiation of allyl alcohol-induced hepatotoxicity. II. In vitro study. J Environ Pathol Toxicol Oncol 2001; 20:155-64. [PMID: 11394714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
We examined the effects of caffeine (C) on allyl alcohol (AA)- and acrolein (A)-induced hepatotoxicity on freshly-isolated, rat hepatocytes obtained from livers of adult, male, Sprague-Dawley rats. Isolated rat hepatocytes in suspension were incubated in each test with one of the following: 0, 1.0, or 2.5 mM of AA alone; or with 0, 2.5, or 5 mM of C alone; or a combination of AA and C at the same range of concentrations as used alone, for 15, 30, 60, 90, and 120 minutes at 37 degrees C. A dose- and time-dependent potentiation of cytotoxicity as measured by cellular viability (using trypan blue exclusion) were observed. The AA (2.5 mM)-induced lactate dehydrogenase (LDH) leakage observed after 60 minutes incubation was completely prevented when pretreated for 15 minutes with 4-methylpyrazole (MP) (0.5 mM). Such pretreatment, even with a double dose of 4-MP, only partially, and not significantly, prevented LDH leakage when the hepatocytes were incubated with a mixture of 2.5 mM AA and 5 mM C. The depletion of hepatocyte nonprotein sulfhydryl (NPSH) content caused by AA was further enhanced in the presence of C, as early as 15 minutes after their exposure. The AA-induced increase in lipid peroxidation was also potentiated by C; however, potentiation started later, and only after sufficient depletion of NPSH (mostly glutathione) occurred resulting from the presence of AA plus C. A significant loss of protein sulfhydryls in rat hepatocytes could be noted following a 60-minute incubation period with either AA (1 mM) or AA (1 mM) plus C (5 mM). Similarly, C produced a dose-and time-dependent potentiation of A-induced liver cytotoxicity, which was preceded by severe loss of NPSH content within 15 minutes of exposure, whereas the potentiation of lipid peroxidation (LPO) resulting from A plus C was found to be a relatively late event, as with AA plus C. Furthermore, combined treatment with AA and C produced a significantly higher cytotoxicity (as measured by cellular viability) than that due to the combined treatment with A plus C based on equimolar concentration. These results suggest that two increased bioactivation pathways of AA involving the P-450 mixed-function oxidase system resulting from C may be involved in the potentiation of AA hepatotoxicity.
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Karas M, Chakrabarti SK. Influence of caffeine on allyl alcohol-induced hepatotoxicity in rats. I. In vivo study. J Environ Pathol Toxicol Oncol 2001; 20:141-54. [PMID: 11394713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
Cotreatment of rats with a low hepatotoxic dose (30.7 mg/kg, i.p.) of allyl alcohol (AA) and a higher, but nontoxic, dose (150 mg/kg, oral) of caffeine (CF) potentiated the hepatotoxicity of AA. This was verified by significantly higher levels of plasma alanine aminotransferase (ALT) activity and histopathologically greater severity of lesions in the periportal hepatocytes than those due to AA alone. Treatment of rats with 4-methylpyrazole (4-MP) (0.5 mmol/kg, i.p.) (an inhibitor liver alcohol dehydrogenase) for 30 minutes, followed by similar cotreatment with AA and CF, completely prevented the elevation of plasma levels of ALT and histological damage induced by cotreatment with CF and AA 24 hours following their administration. Severe liver damage induced by cotreatment with CF and AA was further, markedly enhanced by phenobarbital pretreatment (80 mg/kg, i.p., 3 days). Thus, extensive necrosis of periportal hepatocytes was noted, as well as edema and accumulation of inflammatory cells in the necrotic foci caused by such pretreatment. The depression of hepatic nonprotein sulfhydryls resulting from CF plus AA was much more severe than that caused by AA or CF alone and appeared as early as 30 minutes after administration. However, much less marked depletion of protein thiols was observed following similar treatments. Significant increase in lipid peroxidation (as measured by melondialdehyde [MDA] formation) was also observed in rat liver but only 24 hours after administration. The production ofMDA in the rat liver was significantly higher after administration of AA plus CF than after administration of AA alone. Pretreatment of rats with phenobarbital further significantly enhanced the formation of 2,4-dinitrophenylhydrazine (DNP)-reactive metabolite(s) (measured as DNP-acrolein adduct equivalents) in rat liver induced by AA (30.7 mg/kg) plus CF (150 mg/kg) within 1 hour following such treatment. Cotreatment with AA and a higher dose of CF resulted in significantly higher excretion of urinary thioethers or mercapturic acids than in rats treated with AA alone. Thus, these data suggest that an increased bioactivation pathway of acrolein involving a P450 mixed-function oxidase system caused by CF may be involved in such potentiating effects of CF on AA-induced hepatotoxicity in rats.
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Héron-Milhavet L, Karas M, Goldsmith CM, Baum BJ, LeRoith D. Insulin-like growth factor-I (IGF-I) receptor activation rescues UV-damaged cells through a p38 signaling pathway. Potential role of the IGF-I receptor in DNA repair. J Biol Chem 2001; 276:18185-92. [PMID: 11278917 DOI: 10.1074/jbc.m011490200] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The activated insulin-like growth factor-I receptor (IGF-IR) is implicated in mitogenesis, transformation, and anti-apoptosis. To investigate the role of the IGF-IR in protection from UV-mimetic-induced DNA damage, 4-nitroquinoline N-oxide (4-NQO) was used. In this study we show that the activation of the IGF-IR is capable of rescuing NWTb3 cells overexpressing normal IGF-IRs from 4-NQO-induced DNA damage as demonstrated by cellular proliferation assays. This action was specific for the IGF-IR since cells expressing dominant negative IGF-IRs were not rescued from 4-NQO UV-mimetic treatment. DNA damage induced by 4-NQO in NWTb3 cells was significantly decreased after IGF-IR activation as measured by comet assay. IGF-I was also able to overcome the cell cycle arrest, observed after 4-NQO treatment, thereby enhancing the ability of NWTb3 cells to enter S phase. Interestingly, the p38 mitogen-activated protein kinase pathway was shown to represent the main signaling pathway involved in the IGF-IR-mediated rescue of UV-like damaged cells. The ability of the IGF-IR to induce DNA repair was also demonstrated by infecting NWTb3 cells with UV-irradiated adenovirus. Activation of the IGF-IR resulted in enhanced beta-galactosidase reporter gene activity demonstrating repair of the damaged DNA. This study indicates a direct role of the IGF system in the rescue of damaged cells via DNA repair.
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Lysák D, Koza V, Jindra P, Vozobulová V, Schutzová M, Fiser J, Cerná K, Karas M, Skopek P, Svojgrová M, Vokurka S. Allogeneic BMT in patients above 45 years of age: a single center experience. Bone Marrow Transplant 2001; 27:723-6. [PMID: 11360112 DOI: 10.1038/sj.bmt.1702851] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2000] [Accepted: 01/04/2001] [Indexed: 11/09/2022]
Abstract
Increasing age has been reported to be associated with worse outcome and higher occurrence of complication after allogeneic bone marrow transplantation. We analysed a cohort of 39 patients between the ages of 45 and 57 (median 49 years) with different hematologic malignancies who had undergone BMT in our institution over the preceding 4 years. Pretransplant conditioning consisted of Bu/CY2, GVHD prophylaxis of a combination of cyclosporine and "short" methotrexate. At present 54% of patients remain alive (with a median follow-up 44 months), the probability of survival at 5 years is 53% (5-year DFS 78%). The 5-year survival probability in the control group of younger patients is 53% (P = 0.8003). Main causes of death were GVHD (4 patients, 10%), relapse (5 patients, 13%) and infection (6 patients, 15%). The incidence of acute GVHD grade II-IV was 51% (grade III-IV 0% patients), the incidence of chronic GVHD 49% (limited 18% and extensive 31% patients). Our results suggest that allogeneic BMT can be performed in patients above the age of 45 years with acceptable morbidity and mortality, especially if a family HLA matched donor is available.
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