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On the Trail of Creativity: Dimensionality of Divergent Thinking and its Relation with Cognitive Abilities, Personality, and Insight. EUROPEAN JOURNAL OF PERSONALITY 2020. [DOI: 10.1002/per.2288] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Divergent thinking (DT) is an important constituent of creativity that captures aspects of fluency and originality. The literature lacks multivariate studies that report relationships between DT and its aspects with relevant covariates, such as cognitive abilities, personality traits (e.g. openness), and insight. In two multivariate studies ( N = 152 and N = 298), we evaluate competing measurement models for a variety of DT tests and examine the relationship between DT and established cognitive abilities, personality traits, and insight. A nested factor model with a general DT and a nested originality factor described the data well. In Study 1, DT was moderately related with working memory, fluid intelligence, crystallized intelligence, and mental speed. In Study 2, we replicate these results and add insight, openness, extraversion, and honesty–humility as covariates. DT was associated with insight, extraversion, and honesty–humility, whereas crystallized intelligence mediated the relationship between openness and DT. In contrast, the nested originality factor (i.e. the specificity of originality tasks beyond other DT tasks) had low variance and was not meaningfully related with any other constructs in the nomological net. We highlight avenues for future research by discussing issues of measurement and scoring.
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Individual differences in the variability of oscillatory pre-stimulus activity and their relationship with face-cognition performance. PERSONALITY AND INDIVIDUAL DIFFERENCES 2016. [DOI: 10.1016/j.paid.2016.05.222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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3
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Face and emotion expression processing and the serotonin transporter polymorphism 5-HTTLPR/rs22531. GENES BRAIN AND BEHAVIOR 2016; 15:453-64. [PMID: 27079569 DOI: 10.1111/gbb.12295] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 03/19/2016] [Accepted: 04/08/2016] [Indexed: 12/13/2022]
Abstract
Face cognition, including face identity and facial expression processing, is a crucial component of socio-emotional abilities, characterizing humans as highest developed social beings. However, for these trait domains molecular genetic studies investigating gene-behavior associations based on well-founded phenotype definitions are still rare. We examined the relationship between 5-HTTLPR/rs25531 polymorphisms - related to serotonin-reuptake - and the ability to perceive and recognize faces and emotional expressions in human faces. For this aim we conducted structural equation modeling on data from 230 young adults, obtained by using a comprehensive, multivariate task battery with maximal effort tasks. By additionally modeling fluid intelligence and immediate and delayed memory factors, we aimed to address the discriminant relationships of the 5-HTTLPR/rs25531 polymorphisms with socio-emotional abilities. We found a robust association between the 5-HTTLPR/rs25531 polymorphism and facial emotion perception. Carriers of two long (L) alleles outperformed carriers of one or two S alleles. Weaker associations were present for face identity perception and memory for emotional facial expressions. There was no association between the 5-HTTLPR/rs25531 polymorphism and non-social abilities, demonstrating discriminant validity of the relationships. We discuss the implications and possible neural mechanisms underlying these novel findings.
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Assessing the structural adequacy of alternative ecohydrological models using a pattern-oriented approach. Ecol Modell 2015. [DOI: 10.1016/j.ecolmodel.2015.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
Human babesiosis is caused by the intraerythrocytic parasite of the genus Babesia (phylum Apicomplexa). Humans are commonly infected by the bite of Ixodid ticks. Rarely, transmission does occur perinatal or via contaminated blood transfusion. There is only insufficient data available on the clinical relevance in Europe, whereas there are known endemic states in the United States with an increasing importance of the disease in transfusion medicine. The following article gives an overview of the situation in Germany. Human babesiosis is a zoonotic disease with a worldwide increasing importance according to the increasing number of immunocompromised patients. Clinical symptoms have a wide range from asymptomatic to severe and letal cases. So far, the detection of the parasites in ticks and seroepidemiological data in Europe identified 3 humanpathogenic species: B. microti, B. divergens und B. venatorum (EU1-3). The relative small number of approximately 50 documented human cases is probably due to the lack of knowledge of the disease and the availability of diagnostic tools. Comprehensive systematic investigations of the prevalence in ticks, seroepidemiological data and improved diagnostic tests are urgently needed to evaluate the importance of the parasite.
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Modeling individual differences in facial expressivity. PERSONALITY AND INDIVIDUAL DIFFERENCES 2014. [DOI: 10.1016/j.paid.2013.07.084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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On the genetic basis of face cognition and its relation to fluid cognitive abilities. GENES BRAIN AND BEHAVIOR 2013; 12:438-45. [PMID: 23489762 DOI: 10.1111/gbb.12034] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 10/26/2012] [Accepted: 03/05/2013] [Indexed: 11/29/2022]
Abstract
The oxytocin and the dopaminergic systems have turned out to be highly relevant for social abilities and cognition. Therefore, we examined the association between two functional gene polymorphisms and face cognition (FC) in a multivariate study (N = 250) by applying structural equation modeling. The catechol-O-methyltransferase (COMT) val158met polymorphism influences the enzyme activity of COMT, which affects the prefrontal dopamine concentration. The rs226849 is a single-nucleotide polymorphism located in the promoter region of the oxytocin receptor (OXTR) gene, modulating the mRNA expression. By modeling a general fluid ability factor (defined by working memory and reasoning) and nested FC factors, we tested genetic contributions to FC, after controlling for variance in FC that was also associated with fluid abilities. In line with several previous studies, we found a significant association between the COMT genotype and fluid abilities (Gf) but not with FC. The association between the oxytocin polymorphism and Gf was opposite in direction for men and women. Women with the C(+) genotype performed better on Gf tasks than those with the C(-) genotype. Conversely, men with the C(-) genotype performed better than those with the C(+) genotype. There was no significant association between OXTR and the nested FC factor. Therefore, the relationship between the oxytocin polymorphism and FC can be fully accounted for by Gf. The sex specificity of this relationship is a novel finding and warrants a mechanistic explanation.
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The hormone melatonin stimulates renoprotective effects of "early outgrowth" endothelial progenitor cells in acute ischemic kidney injury. Am J Physiol Renal Physiol 2012; 302:F1305-12. [PMID: 22357919 DOI: 10.1152/ajprenal.00445.2011] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Endothelial progenitor cells (EPCs) protect the kidney from acute ischemic injury. The aim of this study was to analyze whether pretreatment of murine "early outgrowth" EPCs (eEPCs) with the hormone melatonin increases the cells' renoprotective effects in the setting of murine acute ischemic renal failure. Male (8-12 wk old) C57Bl/6N mice were subjected to unilateral ischemia-reperfusion injury postuninephrectomy (40 min). Postischemic animals were injected with either 0.5×10(6) untreated syngeneic murine eEPCs or with cells, pretreated with melatonin for 1 h. Injections were performed shortly after reperfusion of the kidney. While animals injected with untreated cells developed acute renal failure, eEPC pretreatment with melatonin dramatically improved renoprotective actions of the cells. These effects were completely reversed after cell pretreatment with melatonin and the MT-1/-2 antagonist luzindole. In vitro analysis revealed that melatonin reduced the amount of tumor growth factor-β-induced eEPC apoptosis/necrosis. Secretion of vascular endothelial growth factor by the cells was markedly stimulated by the hormone. In addition, migratory activity of eEPCs was enhanced by melatonin and supernatant from melatonin-treated eEPCs stimulated migration of cultured mature endothelial cells. In summary, melatonin was identified as a new agonist of eEPCs in acute ischemic kidney injury.
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Established and emerging pathogens in Ixodes ricinus ticks collected from birds on a conservation island in the Baltic Sea. MEDICAL AND VETERINARY ENTOMOLOGY 2010; 24:425-432. [PMID: 20868431 DOI: 10.1111/j.1365-2915.2010.00905.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Tick-borne pathogens such as Lyme borreliosis spirochaetes, Anaplasma phagocytophilum, Rickettsia spp. and Babesia spp. cause a great variety of diseases in animals and humans. Although their importance with respect to emerging human diseases is increasing, many issues about their ecology are still unclear. In spring 2007, 191 Ixodes ricinus (Acari: Ixodidae) ticks were collected from 99 birds of 11 species on a bird conservation island in the Baltic Sea in order to test them for Borrelia spp., A. phagocytophilum, Rickettsia spp. and Babesia spp. infections. Identification of the pathogens was performed by polymerase chain reaction (PCR), restriction fragment length polymorphism and sequence analysis. The majority of birds with ticks testing positive were European robins and thrushes. Borrelia DNA was detected in 14.1%, A. phagocytophilum in 2.6%, rickettsiae in 7.3% and Babesia spp. in 4.7% of the ticks. Co-infections with different pathogens occurred in six ticks (3.1%). The fact that 11 ticks (five larvae, six nymphs) were infected with Borrelia afzelii suggests that birds may, contrary to current opinion, serve as reservoir hosts for this species. Among rickettsial infections, we identified Rickettsia monacensis and Rickettsia helvetica. As we detected five Rickettsia spp. positive larvae and two birds carried more than one infected tick, transmission of those pathogens from birds to ticks appears possible. Further characterization of Babesia infections revealed Babesia divergens and Babesia microti. The occurrence of Babesia spp. in a total of five larvae suggests that birds may be able to infect ticks, at least with Ba. microti, a species considered not to be transmitted transovarially in ticks.
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Reentrant condensation of proteins in solution induced by multivalent counterions. PHYSICAL REVIEW LETTERS 2008; 101:148101. [PMID: 18851577 DOI: 10.1103/physrevlett.101.148101] [Citation(s) in RCA: 152] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Indexed: 05/26/2023]
Abstract
Negatively charged globular proteins in solution undergo a condensation upon adding trivalent counterions between two critical concentrations C and C, C <C. This reentrant condensation behavior above C is caused by short-ranged electrostatic interactions between multivalent cations and acidic residues, mechanistically different from the case of DNA. Small-angle x-ray scattering indicates a short-ranged attraction between counterion-bound proteins near C and C. Monte Carlo simulations (under these strong electrostatic coupling conditions) support an effective inversion of charge on surface side chains through binding of the multivalent counterions.
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Nitric oxide reduces organ injury and enhances regeneration of reduced-size livers by increasing hepatic arterial flow. Br J Surg 2008; 95:785-92. [DOI: 10.1002/bjs.6139] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Abstract
Background
Reduced-size livers suffer from portal hyperperfusion, diminished arterial blood flow and the risk of postoperative liver injury. The aim of this experimental study was to unravel the role of nitric oxide in this setting.
Methods
Rats underwent 85 per cent partial hepatectomy and either substitution of nitric oxide with molsidomine or inhibition of nitric oxide synthase (NOS) with NG-nitro-l-arginine methyl ester. Untreated hepatectomized animals served as controls and unresected animals as the sham group.
Results
Ultrasonic flowmetry following partial hepatectomy revealed a marked increase in portal venous inflow with a concomitant decrease in hepatic arterial inflow. Nitric oxide substitution counteracted the decline in hepatic arterial inflow and caused a significantly greater increase in cell proliferation after partial hepatectomy compared with control or NOS-inhibited animals. Hepatectomized animals further profited from nitric oxide substitution, as indicated by reduced aminotransferase release and improved liver function.
Conclusion
Nitric oxide improves the postoperative course of rats with reduced-size livers by modulating hepatic macrohaemodynamics and mediating regeneration and cytoprotection, but not by reducing hepatic hyperperfusion and the accompanying sinusoidal shear stress.
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First confirmed autochthonous case of human Babesia microti infection in Europe. Eur J Clin Microbiol Infect Dis 2007; 26:595-601. [PMID: 17587072 DOI: 10.1007/s10096-007-0333-1] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A 42-year-old female patient with acute myeloid leukemia presented with fever and heavy chest pain after her first cycle of specific chemotherapy. Acute myocardial infarction was excluded, but surprisingly, parasitic inclusions in erythrocytes became obvious in Pappenheim and Giemsa-stained peripheral blood smears. The patient did not remember a tick bite but acknowledged having received several blood transfusions in her recent medical history. Suspicion of malaria was ruled out by use of a dip-stick test. The diagnosis of Babesia microti infection was finally established by specific polymerase chain reaction (PCR). Six weeks after initiation of specific treatment, PCR turned negative and a positive immunoflourescence assay (IFA) with an IgG titer of 1:128 indicated seroconversion. Subsequent screening of donors involved in the transfusion of blood products to the patient demonstrated borderline reactivity for Babesia microti (IgG-titer 1:32) in 1 out of 44 individuals. Neither the patient nor the positively tested blood donor had travelled to North America or Asia. Therefore, this is the first confirmed autochthonous human infection in Europe.
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Optical immunosensor for fast and sensitive detection of DDT and related compounds in river water samples. Biosens Bioelectron 2007; 22:1410-8. [PMID: 16870422 DOI: 10.1016/j.bios.2006.06.016] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 06/07/2006] [Accepted: 06/15/2006] [Indexed: 11/29/2022]
Abstract
A surface plasmon resonance (SPR) based immunosensor has been developed for the monitoring of environmentally persistent pollutants like DDT, its metabolites and analogues in real water samples. A reusable immunosurface is provided via the covalent attachment of the analyte derivative to a self-assembled alkanethiol monolayer formed onto the SPR gold-thin layer. The regeneration of the sensor surface allowed the performance of 270 assay cycles within an analysis time of 20 min for each assay cycle. Immunoassays based on a binding inhibition format were performed by using two monoclonal antibodies (MAbs) with different selectivity. Low limits of detection (LODs), in the sub-nanogram per litre range, were attained for DDT-selective (15 ng L-1) and DDT group-selective immunoassays (31 ng L-1). Both assays were carried out in spiked river water samples without significant effect of the matrix. SPR measurements were validated using gas-chromatography-mass spectrometry. The comparison between methods was in good agreement showing an excellent correlation coefficient (r2=0.995). The SPR analysis of DDT proved to be three times more sensitive than colorimetric ELISAs without the need of labelling and a much lower time of response. Our SPR biosensor portable platform (beta-SPR) is already commercialised by the company SENSIA, S.L. (Spain).
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Public knowledge and attitudes on organ donation do not differ in Germany and Spain. Transplant Proc 2006; 38:1218-20. [PMID: 16797267 DOI: 10.1016/j.transproceed.2006.02.105] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2005] [Indexed: 10/24/2022]
Abstract
BACKGROUND The background of this study was the inadequate supply of donor organs in Germany. In Spain, by contrast, a strong increase of organ donors over the past years has created a satisfactory supply situation. Because both countries have similar legal situations, the causes for the drastic differences in organ donation rates remain unclear. The main issue of our study was to investigate the intellectual attitudes toward various aspects of postmortem donations in the populations of both countries as a causative factor for the observed differences. METHODS We studied 726 persons by questionnaire. Probands, matched for age and gender, were recruited among medical students, in a public library and in a general medical practice in both Germany and Spain. RESULTS We found no differences in the attitudes toward postmortem organ donation between the two countries. Differences among the social groups within the countries were apparent in the expected direction. CONCLUSION A higher level of knowledge or a difference in attitudes toward organ donation is probably not the reason for the higher donation rate in Spain. The cause appears to be rather at the organizational level.
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Determination of carbaryl in natural water samples by a surface plasmon resonance flow-through immunosensor. Biosens Bioelectron 2006; 21:2129-36. [PMID: 16309901 DOI: 10.1016/j.bios.2005.10.013] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 10/14/2005] [Accepted: 10/14/2005] [Indexed: 10/25/2022]
Abstract
The analysis of carbaryl in natural water samples was accomplished using a portable immunosensor based on surface plasmon resonance (SPR) technology. The assay was based on a binding inhibition immunoassay format with the analyte derivative covalently immobilized on the sensor surface. An alkanethiol self-assembled monolayer (SAM) was formed onto the gold-coated sensor surface to allow the reusability of the same sensing surface during 220 regeneration cycles. Reproducibility was evaluated by performing three independent assays in triplicate on 3 different days. The batch-assay variability was also calculated using three different gold-coated sensor surfaces. The intra- and inter-day relative standard deviation were 8.6 and 15.3%, respectively, whilst a variation of 7.4% in assay sensitivity was obtained by employing different sensor chips. The lowest detection limit, calculated as the concentration providing a 10% decrease of the blank signal, was of 1.38 microg L(-1). Matrix effects were also evaluated in different water types, showing I50 values (carbaryl concentrations that produced a 50% decrease of the blank signal) within the range of carbaryl standard curves in distilled water (2.78-3.55 microg L(-1)). The carbaryl immunoassay performance was validated with respect to conventional high-performance liquid chromatography-mass spectrometry (HPLC-MS). The correlation between methods was in good agreement (r2 = 0.998, 0.999 and 0.999) for the three types of natural water samples tested. A complete assay cycle, including regeneration, is accomplished in 20 min. All measurements were carried out with the SPR sensor system (beta-SPR) commercialised by the company SENSIA, SL (Spain). The small size and low-time of response of the beta-SPR platform would allow its utilization in real contaminated locations.
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A novel transcriptome subtraction method for the detection of differentially expressed genes in highly complex eukaryotes. Nucleic Acids Res 2005; 33:e136. [PMID: 16147983 PMCID: PMC1201337 DOI: 10.1093/nar/gni136] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We have designed a novel transcriptome subtraction method for the genome-scale analysis of differential gene expression in highly complex eukaryotes, in which suppression subtractive hybridization (SSH) is performed first to enrich the target and, after exchange of adapters, negative subtraction chain (NSC) is then used to eliminate the remaining background. NSC evolved from differential subtraction chain (DSC). We designed novel adapters which make the subtraction system more robust. SSH and NSC were then combined to successfully detect differentially expressed genes in Solanum. The combined technique improves qualitatively upon SSH, the only commercially available transcriptome subtraction system, by detecting target genes in the middle abundance class, to which most differentially expressed genes in highly complex eukaryotes are expected to belong. The main advantage of the combined technique with SSH/NSC is its ability to isolate differentially expressed genes quickly and cost-efficiently from non-standard models, for those microarrays are unavailable.
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Abstract
The accurate modeling of the dielectric properties of water is crucial for many applications in physics, computational chemistry, and molecular biology. This becomes possible in the framework of nonlocal electrostatics, for which we propose a novel formulation allowing for numerical solutions for the nontrivial molecular geometries arising in the applications mentioned before. Our approach is based on the introduction of a secondary field psi, which acts as the potential for the rotation free part of the dielectric displacement field D. For many relevant models, the dielectric function of the medium can be expressed as the Green's function of a local differential operator. In this case, the resulting coupled Poisson (-Boltzmann) equations for psi and the electrostatic potential phi reduce to a system of coupled partial differential equations. The approach is illustrated by its application to simple geometries.
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Prevalence of four species of Borrelia burgdorferi sensu lato and coinfection with Anaplasma phagocytophila in Ixodes ricinus ticks in central Germany. Eur J Clin Microbiol Infect Dis 2003; 22:364-7. [PMID: 12783276 DOI: 10.1007/s10096-003-0926-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A total of 305 Ixodes ricinus ticks collected from three areas of Thuringia in central Germany were investigated for infection with Borrelia burgdorferi sensu lato species and Anaplasma phagocytophila. Overall, 11.1% were infected with Borrelia burgdorferi and 2.3% with Anaplasma phagocytophila. Adult ticks showed a significantly higher rate of infection with both borreliae and Anaplasma phagocytophila. Borrelia garinii (55.9%) was detected most frequently, followed by Borrelia burgdorferi sensu stricto (32.4%), Borrelia afzelii (17.6%), and Borrelia valaisiana (5.9%). Four ticks had dual infection with Borrelia garinii and Borrelia burgdorferi sensu stricto. Two of the Borrelia-positive ticks were coinfected with Anaplasma phagocytophila.
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Characterization of minute differences between genomes of strains of Penicillium nalgiovense using subtractive suppression hybridization without cloning. Lett Appl Microbiol 2002; 35:113-6. [PMID: 12100584 DOI: 10.1046/j.1472-765x.2002.01145.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS Characterization of integrated DNA fragments of unknown base sequences from foreign species using the genetically modified mould Penicillium nalgiovense. METHODS AND RESULTS A modified suppression subtractive hybridization method was deployed in order to detect and characterize foreign genes. Combined with a special two-dimensional polyacrylamide gel electrophoretic technique the usual background was eliminated from the prospective foreign polymerase chain reaction fragments according to their base composition (Müller et al. 1981). CONCLUSIONS AND SIGNIFICANCE AND IMPACT OF THE STUDY DNA fragments obtained from the procedure were suitable for direct DNA sequencing. Each DNA fragment derived from the tester genomic DNA was found to be completely absent in the driver organism.
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Downregulation of beta2-microglobulin in human cord blood somatic stem cells after transplantation into livers of SCID-mice: an escape mechanism of stem cells? Biochem Biophys Res Commun 2002; 294:1052-63. [PMID: 12074584 DOI: 10.1016/s0006-291x(02)00596-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Adherently growing, non-hematopoietic somatic stem cells isolated from human cord blood were stained with the fluorescent dye PKH26 and transplanted into livers of SCID-mice to examine a possible cell fate transition. Already 7 days after transplantation stem cells were well integrated into the liver tissue. Human albumin that was not expressed by the stem cells before transplantation was detectable in the host's livers after injection of cord blood stem cells. Human alpha1-antitrypsin was detectable in stem cells already before transplantation and remained positive in the mouse liver. The most interesting observation in this study was the downregulation of human beta2-microglobulin (beta2M) in the stem cells after transplantation: beta2M is expressed constitutively in our cord blood stem cells. However, beta2M was no longer detectable by RT-PCR in all tissues where human albumin and alpha1-antitrypsin were expressed after stem cell transplantation. beta2M is known to participate as an integral part of the major histocompatibility complex. Absence of beta2M makes the residual heavy chain inactive as an antigen. Thus, downregulation of beta2M may represent an escape mechanism from killer-T cells and may be a molecular mechanism explaining the recently described "immunological blindness" [37] of stem cells. In contrast to the results obtained after direct injection of stem cells as a suspension, no consistent downregulation of beta2M was observed after transplantation of stem cells encapsulated in alginate beads to generate a compartment where stem cells are protected from the host's natural killer cells. No expression of human genes was observed after transplantation of human cord blood derived mononuclear cells (MNC) that were used as a negative control. In conclusion, we have shown that human cord blood somatic stem cells survive and are reprogrammed after transplantation into mouse livers, although a complete transdifferentiation to hepatocytes did not occur within 7 days, since some marker genes (GATA4 and alpha-fetoprotein) were still negative. Switching off expression of beta2M may be part of an intriguing and novel mechanism explaining why stem cells escape the host's immune system.
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Structure prediction of protein complexes by an NMR-based protein docking algorithm. JOURNAL OF BIOMOLECULAR NMR 2001; 20:15-21. [PMID: 11430751 DOI: 10.1023/a:1011216130486] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Protein docking algorithms can be used to study the driving forces and reaction mechanisms of docking processes. They are also able to speed up the lengthy process of experimental structure elucidation of protein complexes by proposing potential structures. In this paper, we are discussing a variant of the protein-protein docking problem, where the input consists of the tertiary structures of proteins A and B plus an unassigned one-dimensional 1H-NMR spectrum of the complex AB. We present a new scoring function for evaluating and ranking potential complex structures produced by a docking algorithm. The scoring function computes a 'theoretical' 1H-NMR spectrum for each tentative complex structure and subtracts the calculated spectrum from the experimental one. The absolute areas of the difference spectra are then used to rank the potential complex structures. In contrast to formerly published approaches (e.g. [Morelli et al. (2000) Biochemistry, 39, 2530-2537]) we do not use distance constraints (intermolecular NOE constraints). We have tested the approach with four protein complexes whose three-dimensional structures are stored in the PDB data bank (Bernstein et al., 1977) and whose 1H-NMR shift assignments are available from the BMRB database. The best result was obtained for an example, where all standard scoring functions failed completely. Here, our new scoring function achieved an almost perfect separation between good approximations of the true complex structure and false positives.
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Abstract
Fruiting body formation (sporulation) is a distinctive, irreversible differentiation process in the life cycle of the slime mold Physarum polycephalum. The most important requirement for sporulation of Physarum is a period of starvation, and normally sporulation proceeds in the light. It is shown here that by omitting the liquid sporulation medium and elevating the temperature from 21 to 25 degrees C, sporulation can occur routinely in the dark. It is further shown that this autocrine signaling in the dark requires calcium ions and malate. A putative sporulation control factor was detected in conditioned media derived from plasmodia starved in the dark, which was then identified as polymalate. As an additional role for this previously detected polyanion, specific for the plasmodial state of Physarum, it is suggested that the secreted compound serves as a source for both malate and calcium ions and thus promotes sporulation without light signaling.
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Two-dimensional agarose gel electrophoresis as a tool to isolate genus- and species-specific repetitive DNA sequences. Anal Biochem 2000; 284:6-10. [PMID: 10933849 DOI: 10.1006/abio.2000.4693] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two-dimensional electrophoresis in agarose gels separates DNA-restriction fragments not only by molecular weight but also according to their AT-cluster content. The method produced genus-specific spot patterns of multicopy DNA fragments of grains as well as spot patterns of highly repetitive DNA fragments of ciliates, demonstrated for barley, spelt, and Tetrahymena. Further investigations in regard to their specificity by hybridization with three other grain species (wheat, oat, and rye) and three ciliate species (Tetrahymena thermophila, Tetrahymena pigmentosa, and Tetrahymena borealis) were performed. The DNA samples from spelt and Tetrahymena were demonstrated to be genus specific for Triticum and species specific for Tetrahymena pyriformis, respectively.
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cDNA cloning and cadmium-induced expression of metallothionein mRNA in the zebra mussel Dreissena polymorpha. Biochem Cell Biol 1999; 77:237-41. [PMID: 10505795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
Using pooled degenerate oligonucleotides inferred from the N-terminal amino acid sequence of Dreissena polymorpha metallothionein and a Cys-X-Cys motif characteristic for known metallothioneins, a 150-bp metallothionein-specific reverse transcription PCR product was generated. The PCR product was used to screen a Dreissena polymorpha cDNA library, and a complete metallothionein cDNA sequence from Dreissena was identified. Four clones with the identical sequence were detected, supporting the idea of a single metallothionein gene in Dreissena. The sequence contains a 141-bp 5' untranslated region and a 572-bp 3' untranslated region with two polyadenylation signals. The coding region spans 219 bp. The deduced amino acid sequence shows 21 cysteine residues present in the metallothionein-typical motifs. Induction studies were performed with 50 microg Cd2+/L for up to 16 days. The exposed mussels show a sevenfold higher metallothionein mRNA level compared with uninduced control mussels.
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Detection of polycyclic aromatic hydrocarbon degradation genes in different soil bacteria by polymerase chain reaction and DNA hybridization. FEMS Microbiol Lett 1999; 173:255-63. [PMID: 10220903 DOI: 10.1111/j.1574-6968.1999.tb13510.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Twenty different strains of Pseudomonas, Mycobacterium, Gordona, Sphingomonas, Rhodococcus and Xanthomonas which degrade polycyclic aromatic hydrocarbons (PAH) were characterized in respect to genes encoding degradation enzymes for PAH. Genomic DNA from these strains was hybridized with a fragment of ndoB, coding for the large iron sulfur protein (ISP alpha) of the naphthalene dioxygenase from Pseudomonas putida PaW736 (NCIB 9816). A group of seven naphthalene-degrading Pseudomonas strains showed strong hybridization with the ndoB probe, and five Gordona, Mycobacterium, Rhodococcus and Pseudomonas strains able to degrade higher molecular weight PAH showed weaker hybridization signals. Using a polymerase chain reaction (PCR) approach, seven naphthalene-degrading Pseudomonas strains showed a PCR fragment of the expected size with ndoB-specific primers and additionally ten strains of Gordona, Mycobacterium, Pseudomonas, Sphingomonas and Xanthomonas able to degrade higher molecular weight PAH were detected with degenerate primer-pools specific for the ISP alpha [2Fe-2S]-Rieske center of diverse aromatic hydrocarbon dioxygenases. This suggests a molecular relationship between genes coding for PAH catabolism in various PAH-degrading bacterial taxa, which could be used to evaluate the PAH-degradation potential of mixed populations.
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Use of manganese in RT-PCR eliminates PCR artifacts resulting from DNase I digestion. Biotechniques 1997; 22:1128-32. [PMID: 9187763 DOI: 10.2144/97226st05] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The precise quantification of rare mRNA copies from intronless genes by reverse transcription polymerase chain reaction (RT-PCR) requires the complete removal of genomic DNA because discrimination of cDNA and DNA amplification products by differing sizes of PCR products is not possible. Elimination of DNA is achieved by treating the RNA sample with RNase-free DNase I before RT-PCR. The lack of a PCR product from DNase-treated RNA samples before RT is usually accepted as a proof of efficient DNA destruction. However, this may vary depending on the metal cofactor used in the DNase I cleavage. Treating DNA-contaminated RNA samples with DNase I and magnesium as a cofactor creates a negative PCR control after digestion without further RT. Paradoxically, after additional RT-PCR, the original intron-containing DNA fragment size may be produced again. In the presence of manganese as cofactor, RT-created DNA fragments do not appear. This is because in the presence of manganese, DNase I cleaves both DNA strands at approximately the same site, yielding DNA fragments that are blunt-ended or that have protruding termini of only one or two nucleotides in length. However, overlapping fragments with the potential to recombine are created by DNase digestion with magnesium as cofactor. Because one cannot differentiate between a PCR signal produced by RNA and one produced by recombined DNA after DNase I digestion and RT, all such DNase I assays should be performed with manganese instead of magnesium.
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[Gamma-linolenic-acid-rich borage seed oil capsules in children with atopic dermatitis. A placebo-controlled double-blind study]. KLINISCHE PADIATRIE 1997; 209:100-4. [PMID: 9244815 DOI: 10.1055/s-2008-1043936] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We investigated the effect of gamma-linolenic-acid from borage seed on atopic dermatitis of children. In a placebo-controlled, double-blind manner we studied 24 patients, 3-17 years old. Every patient received 360 mg of gamma-linolenic acid daily, independent from sex and age; the same amount of corn seed-oil served as placebo. After 10 to 14 weeks of treatment there was no improvement of the eczema in the verum phase compared to placebo. Both groups showed improvement while taking placebo. This result could be seen in the objective investigations (Costa-Score, 3 times per treatment period) as well as in the daily patients documentation. The patients whose eczema has improved under borage seed-oil (n = 10) had no special characteristics, so that we could not identify any responder-type.
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Long-term decline of atmospheric and marine pollution by polycyclic aromatic hydrocarbons (PAHS) in Germany. CHEMOSPHERE 1997; 34:2099-2108. [PMID: 9159907 DOI: 10.1016/s0045-6535(97)00070-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Concentrations of benzo[a]pyrene and benzo[e]pyrene in the atmosphere as markers for the class of PAHs decreased by about 70% within one decade in clean air as well as in industrially polluted areas of Germany when measured with passive samplers (spruce sprouts, poplar and beech leaves). The same trend has been found for East-Germany during 1991-1995. Mussels (Mytilus edulis) were found to accumulate PAHs from the aquatic environment and exhibited a seasonal periodicity of the PAH concentration. After an initial decline from 1985 to 1990, the PAH concentration remained constant until 1995 in the North Sea area investigated.
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Abstract
Fibrosis makes an important contribution to the pathophysiological events leading to the development of heart failure in ischemic and hypertensive heart disease. Since cardiac fibroblasts are mainly responsible for the synthesis and deposition of the extracellular matrix, we have established a method for isolating and cultivating human cardiac fibroblasts from explanted human hearts. The cell yield was 2.14+/-0.25x10(6 )cells in five independent isolations and the cell purity was 95-97%, contaminating cells being vascular smooth muscle cells and pericytes. Cultured cells were studied with respect to growth properties, morphology and deposition of components of the extracellular matrix. Isolated cells displayed a differentiated phenotype, including the second passage in culture; they synthesised collagen I, III, IV, fibronectin, vitronectin, tenascin and chondroitin sulphate and expressed an atypical angiotensin receptor. This atypical angiotensin receptor internalised angiotensins II and III but not angiotensin IV in a time-dependent manner. Stimulation of the cells with angiotensins II and III but not with angiotensin IV resulted in a dose-dependent stimulation of DNA synthesis. Co-incubation with the subtype-specific receptor antagonists Losartan and PD 123317 did not prevent the stimulation of DNA synthesis. The further characterisation of this receptor should provide insights into the pathobiochemical events leading to heart failure in hypertension and ischemic heart disease.
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Aortic valve debridement by ultrasonic surgical aspirator in degenerative, aortic valve stenosis: follow-up with Doppler echocardiography. Eur J Cardiothorac Surg 1996; 10:498-504. [PMID: 8855420 DOI: 10.1016/s1010-7940(96)80414-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVE Recently there has been an emphasis on reconstructing diseases native valves as an alternative to prosthetic valve replacement. Whereas; the surgical repair of aortic valve stenosis has been always problematic. This study was performed to estimate the clinical results after aortic valve debridement using ultrasonic energy. METHODS Between 1990-1994 26 patients underwent ultrasonic aortic valve decalcification. There were 15 females and 11 males, the age was in average 74 years. As a concomitant diagnosis 88% patients (23) had mostly mild, aortic valve insufficiency, 16 (61%) had coronary artery disease and 11 (42%) had mild mitral valve incompetence. All of the patients were operated with cardiopulmonary bypass using moderate hypothermia, cardioplegical arrest and topical cooling for myocardial protection. The calcifications were removed tangentially using Cavitron Ultrasonic Surgical Aspirator. (CUSA), CAVITRON, USA. Leaflet perforation and/or unsatisfactory valve closure have been indications for aortic valve replacement. RESULTS Two operative death (8%) have occurred and six patients have died in the further course (follow-up mean 17 months ranging from 4 to 61 months). Postoperative Doppler-Echocardiography results taken directly after surgery and then again 17 months later (n = 18) showed a decrease of peak and mean gradients across the aortic valve three and two times respectively (p < 0.001). 17 months after debridement we observed a mild rise in both gradients (by peak gradient p < 0.05). Directly postoperative, the aortic valve area increased doubly and decreased 17 months later slight, but it was still statistically significant in comparison with our preoperative data (p < 0.001). Follow-up echocardiography demonstrated late onset of moderate aortic valve insufficiency in 6 patients. The classification of New York Heart Association was improved in 13 (72%) survivors after 17 months. CONCLUSIONS Ultrasonic debridement of aortic valve stenosis allows precise and energy-controlled removal of calcium, increased doubly the valve area and decreased of peak and mean gradients statistically significant. The advantages of preserving the native aortic valve in elderly patients are relative good arguments; although a longer follow-up is necessary to establish this procedure.
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Reversal of multidrug resistance by novel cyclosporin A analogues and the cyclopeptolide SDZ 214-103 biosynthesized in vitro. J Cancer Res Clin Oncol 1995; 121:407-12. [PMID: 7635870 DOI: 10.1007/bf01212947] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
It was shown that cyclopeptolide SDZ 214-103 (10 microM) is more active in rhodamine-123 accumulation in actinomycin-D-resistant human lymphoma cells CCRF/ACTD400 than cyclosporin A (10 microM), but equipotent in the doxorubicin-resistant Friend erythroleukemia cell line F4-6/ADR. In F4-6/ADR cells, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay showed comparable cytotoxic effects of doxorubicin at various concentrations in the presence of SDZ 214-103 and cyclosporin A. For the other novel cyclosporin A analogues minor multidrug-resistance-modulating potency was demonstrated. At equipotent modulating doses of verapamil (10 microM) and cyclosporin A (10 microM) in the MTT assay regarding doxorubicin cytotoxicity, cyclosporin A was efficient in the rhodamine-123-uptake assay while verapamil was not active when identical incubation times were used.
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MESH Headings
- Cyclosporins/biosynthesis
- Cyclosporins/pharmacology
- Dactinomycin/pharmacology
- Doxorubicin/pharmacology
- Drug Interactions
- Drug Resistance, Microbial/physiology
- Drug Resistance, Multiple
- Drug Screening Assays, Antitumor
- Friend murine leukemia virus
- Humans
- Immunosuppressive Agents/pharmacology
- Leukemia, Erythroblastic, Acute/drug therapy
- Leukemia, Erythroblastic, Acute/metabolism
- Leukemia, Erythroblastic, Acute/virology
- Lymphoma/drug therapy
- Lymphoma/metabolism
- Rhodamine 123
- Rhodamines/pharmacokinetics
- Tetrazolium Salts
- Thiazoles
- Tumor Cells, Cultured/drug effects
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Chamber-specific expression of human myocardial proteins detected by two-dimensional gel electrophoresis. Electrophoresis 1995; 16:841-50. [PMID: 7588573 DOI: 10.1002/elps.11501601139] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
High resolution two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), followed by computer-assisted image analysis (PDQUEST) was used to screen atrial and ventricular protein patterns for quantitative and qualitative differences in protein expression. Myocardial proteins from left ventricular (LV) and right atrial (RA) samples from end-stage, failing explanted hearts and from a healthy donor heart (control) were separated by 2-D large gel electrophoresis. Ten RA versus ten LV gels from explanted dilated cardiomyopathic (DCM) hearts were analyzed for quantitative differences in their spot patterns. Of the 197 spots matched to every gel, 40 spots differed significantly in intensity between RA and LV for DCM patients. A larger number of atrial and ventricular gels (20 RA, 20 LV) from DCM patients and from a healthy donor heart (4 RA, 4 LV gels) were analyzed for qualitative differences in protein expression. Three protein spots (SSP 1120: M(r)/pI:20.5 kDa/4.6; SSP 1119: M(r)/pI:20.6 kDa/4.5; SSP 0117:M(r)/pI:20.7/ < 4.5) that are present in all RA gels for DCM patients are absent in all LV gels. Two protein spots (SSP 0112: M(r)/pI:17.2 kDa,/ < 4.4; SSP 0114:M(r)/pI:17.6 kDa/ < 4.4) occur only in all LV gels but not in the RA gels. These five qualitatively differing spots are identical in DCM patients and in the healthy donor heart. Some of the differing spots were internally sequenced and identified as myosin light chain isoforms (myosin light chain 2, atrial; myosin light chain 2, ventricular; myosin light chain 1, atrial) with the Protein Identification Resource (PIR) accession numbers A44451, S03708, A30881, respectively. Additionally, phosphoglycerate mutase (PIR: JQ0750) and ATP synthase alpha chain (PIR: S17193) were identified. Thus, quantitative and qualitative differences between atrial and ventricular protein patterns were identified by 2-D PAGE. A characteristic distribution of myosin light chains between atrial and ventricular human myocardium was found using our approach.
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Abstract
BACKGROUND To assess the chamber localization, subtype distribution, and regulation of human myocardial angiotensin II receptors in heart failure, we determined the binding of angiotensin II, Sar1Ile8-angiotensin II, and the subtype-specific antagonists Dup 753 (AT1-specific) and PD 123319 (AT2-specific) in atria from patients with normal (left ventricular ejection fraction > 55%) or moderately impaired (left ventricular ejection fraction 30% to 55%) cardiac function and in atria and ventricles from explanted end-stage failing hearts. Sarcolemmal and combined fractions, the latter including internalized receptors, were studied. In addition, AT1 mRNA content was analyzed by polymerase chain reaction after reverse transcription. METHODS AND RESULTS The number of angiotensin II binding sites (Bmax) in sarcolemmal fractions was significantly reduced in explanted end-stage failing hearts in comparison with control subjects and moderate heart failure (Bmax 3.9 +/- 0.8 versus 11.2 +/- 1.7 and 9.6 +/- 0.8 fmol/mg protein, respectively). A comparable 65% reduction in receptor numbers was found in combined fractions from end-stage failing hearts, indicating that the loss of binding sites was not due to their internalization. The dissociation constants were comparable in sarcolemmal and combined fractions and in nonfailing and failing hearts, ranging from 0.5 +/- 0.2 to 1.2 +/- 0.5 nmol/L. In nonfailing hearts, 69 +/- 4% of binding sites were blocked by the subtype-2-specific inhibitor PD 123319 and were therefore classified as AT2; 33 +/- 5% were blocked by the subtype-1-specific inhibitor DUP 753 and thus classified as subtype 1. In explanted hearts, comparable ratios of 66 +/- 5% AT2 sites and 34 +/- 5% AT1 sites were found. AT1 cDNA amplification signals by polymerase chain reaction were reduced to about one third of the level in control subjects in end-stage failing hearts. CONCLUSIONS Angiotensin II receptors in human myocardium are present in relatively low numbers, and AT2 is the predominant subtype. A significant loss of angiotensin II receptors occurs in end stage but not in moderate heart failure. The loss of receptors affects both subtypes to a comparable degree. The data suggest that the decrease in receptor density is due to a decrease in steady-state mRNA abundance.
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Characterization of myocardial protein composition in dilated cardiomyopathy by two-dimensional gel electrophoresis. Eur Heart J 1994; 15 Suppl D:37-44. [PMID: 7713112 DOI: 10.1093/eurheartj/15.suppl_d.37] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In order to identify alterations in the myocardial protein pattern that characterize dilated cardiomyopathy (DCM), we compared, by two-dimensional gel electrophoresis, right atrial protein patterns from five patients with DCM and four with normal left ventricular function (two gels per patient). Using computer assisted analysis (PDQUEST, 4.1) we found reproducible protein patterns in the 18 gels (23 x 30 cm, pH 4-9, molecular weight 10-150 kDa). In the two gels from the same patient, 91% of proteins were identical in their position in the pattern and the relative intensities of these protein species correlated with r = 0.85. Three hundred and two +/- 50 protein species were found in several gels, 186 in all 18 gels. Seven proteins in the DCM group were decreased in their relative intensity by > 100%, six were increased by > 100%. Significant quantitative differences between DCM and control patients were found for 25 protein species. Based on seven external marker proteins, a pH and molecular weight value could be calculated for each protein. So far, 30 protein species have been identified by antibodies, amino acid analysis or sequencing procedures. From the 25 proteins that are significantly different between DCM and controls, three have been identified. Expression of the mitochondrial creatine kinase and alpha cristallin B chain was significantly increased in DCM; the malate dehydrogenase family was also significantly decreased in DCM. Two-dimensional electrophoresis appears to be a powerful method for the detection of disease-associated alterations in the myocardial protein pattern.
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Abstract
Impaired production of myocardial cyclic adenosine monophosphate (cAMP) is thought to contribute to contractile dysfunction in end stage heart failure, but myocardial cAMP content has not yet been evaluated in heart failure patients in comparison with controls. We therefore measured the myocardial content of cAMP by radioimmunoassay in endomyocardial biopsies from patients in different stages of heart failure and in controls and correlated it with biochemical and functional parameters. The myocardial content of norepinephrine was determined by HPLC in the same biopsies in order to assess if the myocardium studied was affected by heart failure. Myocardial cAMP (in fmol.microgram-1 non-collagen protein) in 20 patients with heart failure (LVEF: 27 +/- 8%, cAMP: 5.8 +/- 2.0) was unchanged in comparison with eight controls (LVEF: 64 +/- 4.7%, cAMP, 4.9 +/- 2.1). In contrast, myocardial norepinephrine (in pg.microgram-1 non-collagen protein) in the same biopsies was significantly reduced in heart failure (4.0 +/- 3.0) in comparison with the same controls (11.5 +/- 3.0, P < 0.0002). Plasma cAMP in 20 heart failure patients (22.0 +/- 4.2 pmol.l-1) was not different from controls(22.0 +/- 7.8), whereas plasma norepinephrine was increased (heart failure: 460 +/- 257 pg.ml-1, controls 182 +/- 49, P < 0.001). Myocardial cAMP levels are indistinguishable from controls in human heart failure and therefore do not contribute to a further characterization of the cardiac adrenergic system in these patients. This is most likely due to the impossibility of obtaining biopsies with truly unstimulated adenylyl cyclase activity.
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Isolation and characterization of macrovascular and microvascular endothelial cells from human hearts. THE AMERICAN JOURNAL OF PHYSIOLOGY 1994; 267:H2138-48. [PMID: 7810713 DOI: 10.1152/ajpheart.1994.267.6.h2138] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In vivo models to investigate mechanisms of local hemostasis in the macro- and microvascular coronary circulation are not available. Therefore, we established a culture system of human macro- and microvascular endothelial cells with high cellular yield and high endothelial cell purity. Microvascular endothelial cells from human hearts were isolated by enzymatic treatment of cardiac muscle preparations obtained during heart transplantation. The isolated microvessels were used to start cultures that were subsequently separated and purified from contaminating nonendothelial cells by paramagnetic beads linked to the lectin Ulex europaeus agglutinin I. Macrovascular endothelial cells were isolated from epicardial coronary arteries and purified by paramagnetic beads as well. With this method high purity (< 2% nonendothelial cells) was achieved as judged from fluorescence-activated cell sorting. Immunochemistry demonstrated the expression of several typical endothelial markers. The two endothelial cell types displayed functional heterogeneity in respect to bradykinin degradation and plasminogen activator inhibitor-1 activity. Thus the ability to selectively isolate and culture human macro- and microvascular cardiac endothelial cells provides a valuable tool to systematically investigate endothelial function in human hearts.
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Human cardiac fibroblasts express an angiotensin receptor with unusual binding characteristics which is coupled to cellular proliferation. Biochem Biophys Res Commun 1994; 204:1334-9. [PMID: 7980612 DOI: 10.1006/bbrc.1994.2609] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
To assess the cellular localization of angiotensin receptors in human heart, we isolated human cardiac fibroblasts from explanted end-stage failing human hearts. As judged by an immunofluorescence assay, the isolated cells consisted of 96% of fibroblasts. Using receptor binding studies, we could identify a single angiotensin binding site on these cells, with a Kd of 0.6nM and a Bmax of 1.5 fmol/mg protein. Inhibiting concentrations 50 for Ang II and Ang I/II (1-7) were 40nM and 10nM, respectively. Stimulation with Ang II (100 nM) and Ang I/II (1-7) (100nM) led to cellular proliferation which could not be inhibited by Losartan or PD 123319. These results suggest that human cardiac fibroblasts express an as yet unknown angiotensin receptor-subtype.
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Dilated cardiomyopathy: computer-assisted analysis of endomyocardial biopsy protein patterns by two-dimensional gel electrophoresis. EUROPEAN JOURNAL OF CLINICAL CHEMISTRY AND CLINICAL BIOCHEMISTRY : JOURNAL OF THE FORUM OF EUROPEAN CLINICAL CHEMISTRY SOCIETIES 1994; 32:615-24. [PMID: 7529573 DOI: 10.1515/cclm.1994.32.8.615] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In order to identify disease-associated alterations in the myocardial protein patterns in dilated cardiomyopathy, we used 2-dimensional gel electrophoresis to analyse the proteins of endomyocardial biopsies from patients and controls. Proteins (150 micrograms) from biopsies (1-3 mg wet weight) were first separated by isoelectric focusing, then applied to large 2-dimensional gels. A computer-assisted system (PDQUEST) was used for spot detection, quantification and comparison of 2-dimensional protein patterns. From a single endomyocardial biopsy about 1000 different protein species were resolved. The spot pattern was influenced by the concentration of protein during sample preparation, by the amount of protein loaded onto the gels and by the development time of silver staining. Variances of spot position in the first and second dimension and in the long diagonals were less than 5%. Coefficients of variance for the spot quantities in 8 gels were 16 +/- 8%. Contaminating blood proteins could be identified in the biopsy patterns. Computer-assisted comparison between cardiomyopathy (n = 5) and controls (n = 5) over the whole gel revealed that 55 protein spots were increased 100%, 27 protein spots decreased 100%. Four proteins showed significant quantitative differences between the cardiomyopathic hearts and controls. Fourteen proteins were identified by amino acid analysis or microsequencing. An isoelectric point and molecular mass grid was laid over the whole gel based on these identified protein species, resulting in approximate isoelectric point values and molecular masses for all other protein species. Thus, myocardial 2-dimensional protein patterns obtained from endomyocardial biopsies can be used for the characterization of cardiac diseases.
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Tissue kallikrein activity and kinin release in human endothelial cells. EUROPEAN JOURNAL OF CLINICAL CHEMISTRY AND CLINICAL BIOCHEMISTRY : JOURNAL OF THE FORUM OF EUROPEAN CLINICAL CHEMISTRY SOCIETIES 1994; 32:495-500. [PMID: 7981328 DOI: 10.1515/cclm.1994.32.7.495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The kininogenase, tissue kallikrein (EC 3.4.21.8), has been identified in different blood vessels. The enzyme was mainly found in vascular smooth muscle cells. It is not known whether it is present and functionally active in vascular endothelial cells. The following study investigates the presence of tissue kallikrein in endothelial cells from human umbilical veins and pulmonary arteries. Tissue kallikrein was demonstrated in three ways: 1) by immunostaining in endothelial cells; 2) by measurement of tissue kallikrein activity using a colorimetric assay; 3) by the measurement of kinin release in intact and homogenised endothelial cells with a radioimmunoassay. Immunostaining demonstrated the presence of tissue kallikrein in endothelial cells from human umbilical veins and endothelial cells from human pulmonary arteries. Tissue kallikrein-like activity, measured by the degradation of D-Val-cyclohexyl-Ala-Arg-4-nitraniline, was 3.57 +/- 0.5 mU/10(6) endothelial cells from human umbilical veins and 7.52 +/- 0.84 mU/10(6) endothelial cells from human pulmonary arteries. Intracellular kinin concentrations were 424 +/- 83 pg/10(6) cells in endothelial cells from human umbilical veins and 576 +/- 146 pg/10(6) cells in endothelial cells from human pulmonary arteries, and they increased in a time-dependent manner after homogenisation. The increase was abolished by aprotinin (1000 kIU), an inhibitor of tissue kallikrein in both cell types. Addition of exogenous kallikrein (5 mU) to homogenised cells led to a five fold increase of kinin concentrations after five minutes, indicating a sufficient resource of cellular kininogen. Removal of extracellularly bound kininogen by washing with dextran sulphate (100 mg/l) resulted in an approximately 75% reduction of the cellular kinin release.(ABSTRACT TRUNCATED AT 250 WORDS)
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A highly conserved repetitive sequence from Physarum polycephalum contains nucleotide arrangements similar to replicator sequences. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1216:129-33. [PMID: 8218403 DOI: 10.1016/0167-4781(93)90049-j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
An interspersed repetitive sequence from Physarum polycephalum has been cloned and analysed. The 394 bp sequence is highly conserved and contains several homopolymeric (dA)-(dT) tracts capable of forming bent DNA structures and a 10/11 match to the yeast-ARS-consensus sequence. The repetition frequency of the described sequence is about 3000 to 7000, a number that would fit with the distribution of replicator segments in Physarum.
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Nucleotide sequences of the 23S rRNA genes from Bordetella pertussis, B.parapertussis, B.bronchiseptica and B.avium, and their implications for phylogenetic analysis. Nucleic Acids Res 1993; 21:3320. [PMID: 7688118 PMCID: PMC309774 DOI: 10.1093/nar/21.14.3320] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
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Effect of angiotensin-converting-enzyme inhibition on bradykinin metabolism by vascular endothelial cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1993; 264:H1493-7. [PMID: 8388656 DOI: 10.1152/ajpheart.1993.264.5.h1493] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The degradation of bradykinin by angiotensin-converting-enzyme (ACE) activity in cultured human endothelial cells was studied by direct measurement of bradykinin and by its effect on the release of endothelium-derived relaxing factors. The half-life of exogenous bradykinin (10,000 pg/ml) was calculated from the decay of the bradykinin concentration as 46 +/- 2 min in cell monolayers, 133 +/- 15 min in conditioned medium, and 24 +/- 2 min in homogenates. Most of the bradykinin-degrading activity in cell monolayers could be inhibited in a concentration-dependent manner by the ACE inhibitors lisinopril, ramiprilat, and captopril. Bradykinin-degrading activity was released into the culture medium containing one-fourth of the bradykinin-degrading activity found in the presence of cell monolayers. In cell homogenates higher unspecific bradykinin-degrading activities were present. The functional consequence of bradykinin degradation was demonstrated by the potentiating effect of ramiprilat on the generation of endothelium-derived relaxing factors nitric oxide and prostacyclin from endothelial cells. The study supports the concept of increased vasodilatory effects of bradykinin during ACE inhibition.
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FK 506: short- and long-term treatment after cardiac transplantation in nonhuman primates. Transplant Proc 1991; 23:509-10. [PMID: 1703694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Abstract
Plasmodia of the myxomycete Physarum polycephalum (strain Cl) were collected at different times during the cell cycle and extracts were prepared from homogenates using a buffer optimized for microinjection into plasmodial veins. These extracts were injected into plasmodia during the first 3 h of the cell cycle. The time of the following mitosis was monitored and compared with that of the buffer-injected controls. Extracts of plasmodia homogenized 45 min before late telophase accelerated the onset of mitosis in the injected plasmodium up to 70 min, i.e., an advance of 10-14% compared to the 8- to 10-h cell cycle duration of the controls. The accelerating activity vanished completely after heating, freezing, or protease digestion, thus indicating the peptide nature of the active agent. Purification of the active compound by means of gel filtration revealed a molecular mass of about 2500 Da. The active portion of the extract was further fractionated by HPLC and the activity determined in a single peak.
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Heterotopic heart transplantation: mid-term hemodynamic and echocardiographic analysis--the concern of arteriovenous-valve incompetence. THE JOURNAL OF HEART TRANSPLANTATION 1990; 9:675-81; discussion 682. [PMID: 2277307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
To assess the hemodynamic contribution of both hearts after heterotopic heart transplantation, we examined recipients by cardiac catheterization and Doppler echocardiography. Since September 1984, immunosuppression consisted of cyclosporine, azathioprine, methylprednisolone, and antithymocyte globulin. In this time interval, 55 orthotopic and 14 heterotopic transplants have been performed. The indications for heterotopic transplant were elevated pulmonary vascular resistance (greater than 4 Wood units), in 10 patients, or gross (greater than 20%) donor-recipient weight mismatch, in six patients. Two patients belonged to both groups. The 1-year survival rate was 63%; currently seven of the 14 patients are alive. Cardiac output (as measured by dye dilution curves and by the Fick method) increased from 4.2 L/min preoperatively to 6.1 L/min in both groups postoperatively (mean follow up, 5.3 months; p less than 0.0005); the transpulmonary gradient fell from 18.5 to 12.3 mm Hg, the pulmonary vascular resistance from 4.4 to 2.4 Wood units (p less than 0.01). The echocardiographic findings were as follows: left ventricular end-diastolic diameter (mm) in the recipient heart was 67.4 +/- 12 and in the donor heart, 42.6 +/- 8.7. Fractional shortening (%) in the recipient heart was 7.1 +/- 2.9 and in the donor heart, 30.4 +/- 10.4. The Doppler technique revealed a cardiac output contribution-ratio (CO donor/CO recipient) of 3.0 +/- 0.61 on average. In all recipient hearts mild and moderate mitral and tricuspid regurgitation was discovered. In the donor heart all mitral and tricuspid valves were found to be incompetent; this was severe in 66% and 11% of the mitral and tricuspid valves, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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15-Deoxyspergualin for induction of graft nonreactivity after cardiac and renal allotransplantation in primates. Transplantation 1990; 50:181-5. [PMID: 2382284 DOI: 10.1097/00007890-199008000-00001] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In order to assess the immunosuppressive potentials of 15-deoxyspergualin (15-DS) in a preclinical experiment, heterotopic cardiac (n = 27, group I) and classic renal (n = 25, group II) allotransplantations were performed in Chacma baboons. The following immunosuppressive regimens were applied: Groups IB and IIB were treated with 15-DS alone (4 mg/kg/day) for p.o. days 0-9. Groups IC and IIC were treated with cyclosporine A (10-40 mg/kg/day) for p.o. days 0-30. Groups ID and IID received a combination of 15-DS (for p.o. days 0-9) and CsA (for p.o. days 0-30). Groups IA and IIA served as control and received no medication. The mean graft survival was 11.0 days for group IA, 28.2 days for group IB (P less than 0.05; IB vs. IA), 32.4 days for group IC, and 43.1 days for group ID (P less than 0.025; ID vs. IA). After renal transplantation, the corresponding figures were 12.3 days for group IIA, 8.5 days for group IIB, 30.4 days for group IIC and 148.9 days for group IID (P less than 0.025; IID vs. IIA). After cardiac and renal transplantation, acute rejection was the main cause of graft failure. Treatment-related side effects, mainly gastrointestinal complications, were observed only in primates, who were treated with 15-DS alone. After cardiac transplantation, permanent graft non-reactivity was not achieved, but a delayed rejection occurred within a mean of 21.8 days after immunosuppression had been stopped. Following renal transplantation, graft nonreactivity was also not achieved in groups IIB and IIC. In group IID, however, 4 of 8 animals (50%) were graft-tolerant 340, 256, 244, and 164 days after treatment discontinuation. Thus, the combination of 15-DS and CsA led to a significant prolongation of graft survival in both groups. Long-term nonreactivity was achieved only after renal transplantation, when initially treated with 15-DS and CsA.
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15-Deoxyspergualin after cardiac and renal allotransplantation in primates. Transplant Proc 1990; 22:1618-9. [PMID: 2389423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Nuclear polyphosphate as a possible source of energy during the sporulation of Physarum polycephalum. Arch Biochem Biophys 1989; 275:215-23. [PMID: 2817896 DOI: 10.1016/0003-9861(89)90366-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
31P NMR spectroscopic analysis of the polyphosphate pool in cellular and nuclear extracts of Physarum polycephalum demonstrates that plasmodia and cysts contain inorganic polyphosphates with an average chain length of about 100 phosphates. However, only during sporulation are these high-molecular-weight polyphosphates degraded to a lower molecular weight corresponding to an average chain length of about 10 phosphates. Since polyphosphates are degraded even in the presence of a sufficiently large pool of inorganic phosphate, produced by intracellular injection, we conclude that the degradation of polyphosphates serves in supplying energy for biosynthesis during sporulation rather than in increasing the availability of phosphate.
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Heterotopic heart transplantation in 1988--recent selective indications and outcome. THE JOURNAL OF HEART TRANSPLANTATION 1989; 8:381-6. [PMID: 2795280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Considering a worldwide average 1-year survival rate of nearly 90% after orthotopic heart transplantation, the question arises as to whether there is still an indication for heterotopic heart transplantation. Since 1967, 132 heart transplantations have been performed at our institution. From 1974 to 1983 only heterotopic transplantations were performed. Since 1985, quadruple-drug therapy has been used for immunosuppression. This consists of low dose cyclosporine in combination with azathioprine, methylprednisolone (in lower dosages), and rabbit antithymocyte globulin (for the first 4 to 6 days after operation and as rescue therapy for severe rejections). Fifty-five transplantations have been performed with this therapy (44 orthotopic and 11 heterotopic). The indications for heterotopic transplantations were either elevated pulmonary vascular resistance (4 to 6 Wood units, n = 6), or a gross donor and recipient weight mismatch (more than 20%) in candidates who showed signs of severe cardiac decompensation (n = 6). One patient had both indications. The 1-year survival rate for those patients was 83%. Currently seven of the 11 patients are alive with life spans ranging from 6 months to 2.5 years after operation. Causes of deaths were infections (n = 3) and chronic graft rejection (n = 1). The recipients were restudied with right-sided heart catheterizations performed from 2 months to 2 years after transplantation. In all patients the cardiac output increased significantly from a mean of 4.0 to 5.8 L/min (p less than 0.0005). In patients with elevated pulmonary vascular resistance, this value decreased after heterotopic transplantation from a mean of 4.9 to 2.4 Wood units.(ABSTRACT TRUNCATED AT 250 WORDS)
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