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Structural, chemical, and magnetic investigation of a graphene/cobalt/platinum multilayer system on silicon carbide. NANOTECHNOLOGY 2024; 35:165702. [PMID: 38211321 DOI: 10.1088/1361-6528/ad1d7b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 01/11/2024] [Indexed: 01/13/2024]
Abstract
We investigate the magnetic interlayer coupling and domain structure of ultra-thin ferromagnetic (FM) cobalt (Co) layers embedded between a graphene (G) layer and a platinum (Pt) layer on a silicon carbide (SiC) substrate (G/Co/Pt on SiC). Experimentally, a combination of x-ray photoemission electron microscopy with x-ray magnetic circular dichroism has been carried out at the Co L-edge. Furthermore, structural and chemical properties of the system have been investigated using low energy electron diffraction (LEED) and x-ray photoelectron spectroscopy (XPS).In situLEED patterns revealed the crystalline structure of each layer within the system. Moreover, XPS confirmed the presence of quasi-freestanding graphene, the absence of cobalt silicide, and the appearance of two silicon carbide surface components due to Pt intercalation. Thus, the Pt-layer effectively functions as a diffusion barrier. The magnetic structure of the system was unaffected by the substrate's step structure. Furthermore, numerous vortices and anti-vortices were found in all samples, distributed all over the surfaces, indicating Dzyaloshinskii-Moriya interaction. Only regions with a locally increased Co-layer thickness showed no vortices. Moreover, unlike in similar systems, the magnetization was predominantly in-plane, so no perpendicular magnetic anisotropy was found.
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Historical Factors Associated With Past Environments Influence the Biogeography of Thermophilic Endospores in Arctic Marine Sediments. Front Microbiol 2019; 10:245. [PMID: 30873129 PMCID: PMC6403435 DOI: 10.3389/fmicb.2019.00245] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 01/29/2019] [Indexed: 11/13/2022] Open
Abstract
Selection by the local, contemporary environment plays a prominent role in shaping the biogeography of microbes. However, the importance of historical factors in microbial biogeography is more debatable. Historical factors include past ecological and evolutionary circumstances that may have influenced present-day microbial diversity, such as dispersal and past environmental conditions. Diverse thermophilic sulfate-reducing Desulfotomaculum are present as dormant endospores in marine sediments worldwide where temperatures are too low to support their growth. Therefore, they are dispersed to here from elsewhere, presumably a hot, anoxic habitat. While dispersal through ocean currents must influence their distribution in cold marine sediments, it is not clear whether even earlier historical factors, related to the source habitat where these organisms were once active, also have an effect. We investigated whether these historical factors may have influenced the diversity and distribution of thermophilic endospores by comparing their diversity in 10 Arctic fjord surface sediments. Although community composition varied spatially, clear biogeographic patterns were only evident at a high level of taxonomic resolution (>97% sequence similarity of the 16S rRNA gene) achieved with oligotyping. In particular, the diversity and distribution of oligotypes differed for the two most prominent OTUs (defined using a standard 97% similarity cutoff). One OTU was dominated by a single ubiquitous oligotype, while the other OTU consisted of ten more spatially localized oligotypes that decreased in compositional similarity with geographic distance. These patterns are consistent with differences in historical factors that occurred when and where the taxa were once active, prior to sporulation. Further, the influence of history on biogeographic patterns was only revealed by analyzing microdiversity within OTUs, suggesting that populations within standard OTU-level groupings do not necessarily share a common ecological and evolutionary history.
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Crystal structure of 1,2,3-tri-tert-butyl-1,2,3-triphosphetan-4-one,((CH 3) 3C) 3P 3CO. Z KRIST-CRYST MATER 2015. [DOI: 10.1524/zkri.1993.208.12.338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Notizen: Synthese von zwei neuen salzartigen Cyclophosphazenen. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2014. [DOI: 10.1515/znb-1967-1225] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Synthese und Struktur aminosubstituierter Tetraphosphetane / Synthesis and Structure of Amino-Substituted Tetraphosphetanes. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/znb-1991-0705] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A number of aminotetraphosphetanes could be obtained by reductive dehalogenation of dichlorophosphines with magnesium as well as by elimination of chlorotrimethylsilane from vicinal chlorosily-functionalized biphosphines and from [2+2]-cyclodimerization of aminodiphosphenes, respectively. The molecular structures of several tetraphosphetanes are reported and discussed. The torsion-angle of the four-membered rings varies from 22.5° to 45.7°, depending on the size and electronegativity of the exocyclic ligands.
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Notizen: Reaktionen des Nitrosylchlorids mit einigen Nichtmetalliminen. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2014. [DOI: 10.1515/znb-1969-0731] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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1H-NMR-Untersuchungen an Substanzen mit Schwefel-Stickstoff- und Phosphor-Stickstoff-Bindungen. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2014. [DOI: 10.1515/znb-1968-0905] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Die chemischen Verschiebungen der Protonen von Derivaten des S,S-Dimethylsulfodiimins wurden bestimmt. Bei der Messung der 31P-1H-Kopplungskonstanten von phosphorhaltigen Derivaten wurde eine interessante Long-Range-Kopplung über zwei Heteroatome und 1 C-Atom festgestellt, die durch Doppelresonanz-Experimente bestätigt wird. Die anomale chemische Verschiebung und einige Austauscheffekte machen den Ylidcharakter der PCP-Gruppierung in zwei vom Dimethylsulfodiimin abgeleiteten Cyclophosphazenen wahrscheinlich.
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Notizen: 1.5-Dimethyl-3.7-tetraphenyl-1.5-dithiaVI-3.7-diphosphav-2.4.6.8-tetrazocin, ein neues, nur Schwefel, Stickstoff und Phosphor enthaltendes 8-gliedriges Ringsystem. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2014. [DOI: 10.1515/znb-1969-1236] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Abstract
OBJECTIVES Until now, the significance of plasma exchange (PE) as a treatment for steroid-unresponsive optic neuritis (ON) is still unclear because placebo-controlled and larger studies are missing. We report our experience with 23 patients treated by PE due to steroid-unresponsive ON. MATERIALS AND METHODS Patients were admitted to the University Medical Center Hamburg-Eppendorf between 2006 and 2010 with a visual acuity of <50% on the affected eye following steroid treatment. Ten patients suffered from RR-MS, one from neuromyelitis optica, and 12 patients developed ON as a clinically isolated syndrome. Routinely, they were treated with five cycles of PE. Visual acuity was measured before and directly after PE and during follow-up (first follow-up after 50 days, second follow-up after 174 days). RESULTS Altogether, 70% of our patients improved after PE, 69% of them showed a good or very good response to therapy. Patients who improved well after PE (n = 11) showed a mean visual acuity of 16% before PE compared to 45% immediately after PE and 60% at the first follow-up. No serious adverse events occurred. CONCLUSIONS To our knowledge, our study is the largest case series of patients with steroid-unresponsive ON treated with PE. Based on our experience, we conclude that PE is an important treatment option for patients with steroid-unresponsive ON although placebo-controlled studies are missing until now.
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Shaping biological knowledge: applications in proteomics. Comp Funct Genomics 2011; 5:190-5. [PMID: 18629073 PMCID: PMC2447358 DOI: 10.1002/cfg.379] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2003] [Revised: 12/12/2003] [Accepted: 12/18/2003] [Indexed: 12/01/2022] Open
Abstract
The central dogma of molecular biology has provided a meaningful principle
for data integration in the field of genomics. In this context, integration reflects
the known transitions from a chromosome to a protein sequence: transcription,
intron splicing, exon assembly and translation. There is no such clear principle for
integrating proteomics data, since the laws governing protein folding and interactivity
are not quite understood. In our effort to bring together independent pieces of
information relative to proteins in a biologically meaningful way, we assess the bias of
bioinformatics resources and consequent approximations in the framework of small-scale
studies. We analyse proteomics data while following both a data-driven (focus
on proteins smaller than 10 kDa) and a hypothesis-driven (focus on whole bacterial
proteomes) approach. These applications are potentially the source of specialized
complements to classical biological ontologies.
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Objective response evaluations using RECIST criteria: Performance of duplicate readings. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.6602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
6602 Background: Duplicate readings using the RECIST criteria are the current practice for objective response evaluation in cancer trials. In this study we evaluated the agreement in the duplicate readings and the reasons of discrepancies. Methods: 179 subjects participating in a prospective trial with advanced or metastatic renal cell carcinoma were included. Imaging data consisted of chest, abdomen and pelvis CT scans. Additional imaging studies included brain CT scans at baseline and any additional images there were performed at follow up visits. The median number of total visits collected was seven. Duplicate independent evaluations using the RECIST criteria were performed by two trained onco-radiologists. The evaluations included the identification and measurement of target lesions and non- target lesions as well as new lesions. For each visit an overall response was assigned. At the conclusion of the evaluations a best response and the date of the best response were recorded. Criteria of agreement between the two radiologists were based on the best response, the date of best response and the date of progression. Results: There was perfect agreement in 145 (81.1%) of the patients. For 34 (18.9%) there was disagreement in the best response: n=14 (7.8%), in the date of best response: n=7 (3.9%) and the date of progression: n=28 (15.6%). Of the 34 patients, disagreement was on one criterion in 24 (13.4%), 2 criteria for 7 (3.9%) and all three criteria for 3 (1.6%). Conclusions: For objective response evaluations using the RECIST criteria, using the best response and time to progression as criteria for comparison of duplicate independent radiologist evaluations yields to a very good level of agreement. [Table: see text]
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Changes in the multi-joint kinematics and co-ordination after repetitive windsurfing pumping task. J Sports Med Phys Fitness 2004; 44:249-57. [PMID: 15756163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
AIM This study investigated the change in kinematics after repetitive continuous maximal windsurfing pumping on a simulator by utilizing 3-D motion analysis. METHODS Six competitive windsurfers exercised on a tailor-made simulator. The wind force was simulated by attaching the boom to the power head of a rowing ergometer. The exercise consisted of 3 sets of 3-minute maximum pumping. The motion of wrist, elbow, shoulder (on sagittal and frontal planes), waist, hip, knee and ankle joints were recorded by 2 video cameras. Kinematic analysis included the assessment of the change of the range of motion, movement speed (pulling phase and the whole pumping cycle), as well as the movement pattern of all tested joints. RESULTS Modified motor strategy was documented by the significant drop of vertical excursion of the body centre of mass. Moreover, the ankle plantar flexors and dorsiflexors, mid-deltoid as well as wrist extensor and flexor, had significant change of movement according to the assessed parameters. Therefore, they may be the muscles that were more influenced than the other assessed muscles after continuous maximal pumping. The change of muscle co-ordination may be a compensation mechanism to maintain work output. CONCLUSIONS Findings in this study may suggest the importance of implementing specific muscle training program for the competitive windsurfers to increase the pumping capacity.
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Alkaliflexus imshenetskii gen. nov. sp. nov., a new alkaliphilic gliding carbohydrate-fermenting bacterium with propionate formation from a soda lake. Arch Microbiol 2004; 182:244-53. [PMID: 15340778 DOI: 10.1007/s00203-004-0722-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2004] [Revised: 07/25/2004] [Accepted: 07/28/2004] [Indexed: 10/26/2022]
Abstract
Anaerobic saccharolytic bacteria thriving at high pH values were studied in a cellulose-degrading enrichment culture originating from the alkaline lake, Verkhneye Beloye (Central Asia). In situ hybridization of the enrichment culture with 16S rRNA-targeted probes revealed that abundant, long, thin, rod-shaped cells were related to Cytophaga. Bacteria of this type were isolated with cellobiose and five isolates were characterized. Isolates were thin, flexible, gliding rods. They formed a spherical cyst-like structure at one cell end during the late growth phase. The pH range for growth was 7.5-10.2, with an optimum around pH 8.5. Cultures produced a pinkish pigment tentatively identified as a carotenoid. Isolates did not degrade cellulose, indicating that they utilized soluble products formed by so far uncultured hydrolytic cellulose degraders. Besides cellobiose, the isolates utilized other carbohydrates, including xylose, maltose, xylan, starch, and pectin. The main organic fermentation products were propionate, acetate, and succinate. Oxygen, which was not used as electron acceptor, impaired growth. A representative isolate, strain Z-7010, with Marinilabilia salmonicolor as the closest relative, is described as a new genus and species, Alkaliflexus imshenetskii. This is the first cultivated alkaliphilic anaerobic member of the Cytophaga/ Flavobacterium/ Bacteroides phylum.
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High statistics measurement of the K+-->pi0e+nu (K+e3) branching ratio. PHYSICAL REVIEW LETTERS 2003; 91:261802. [PMID: 14754040 DOI: 10.1103/physrevlett.91.261802] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2003] [Indexed: 05/24/2023]
Abstract
E865 at the Brookhaven National Laboratory AGS collected about 70 000 K(+)(e3) events to measure the K(+)(e3) branching ratio relative to the observed K+-->pi(+)pi(0), K+-->pi(0)micro(+)nu, and K+-->pi(+)pi(0)pi(0) decays. The pi(0) in all the decays was detected using the e(+)e(-) pair from pi(0)-->e(+)e(-)gamma decay and no photons were required. Using the 2002 Particle Data Group branching ratios for the normalization decays, we obtain BR(K(+)(e3(gamma)))=(5.13+/-0.02(stat)+/-0.09(syst)+/-0.04(norm))%, where K(+)(e3(gamma)) includes the effect of virtual and real photons. This result is approximately 2.3sigma higher than the current Particle Data Group value. Implications for the V(us) element of the CKM matrix, and the matrix's unitarity are discussed.
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Experimental study of the radiative decays K+-->mu(+)nue(+)e(-) and K+-->e(+)nue(+)e(-). PHYSICAL REVIEW LETTERS 2002; 89:061803. [PMID: 12190577 DOI: 10.1103/physrevlett.89.061803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2002] [Indexed: 05/23/2023]
Abstract
Experiment 865 at the Brookhaven Alternating Gradient Synchrotron obtained 410 K+-->e(+)nue(+)e(-) and 2679 K+-->mu(+)nue(+)e(-) events including 10% and 19% background. The branching ratios were measured to be [2.48+/-0.14(stat)+/-0.14(syst)]x10(-8) (m(ee)>150 MeV) and (7.06+/-0.16+/-0.26)x10(-8) (m(ee)>145 MeV), respectively. Results for the decay form factors are presented.
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[PACS: from project to reality. Report of experiences on full digitalisation of the radiology department of a major hospital]. Radiologe 2002; 42:119-24. [PMID: 11963246 DOI: 10.1007/s001170100650] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To assess the time needed and the resulting effects of a complete digitalisation of a radiological department of a major hospital (856 beds, 28,000 in-patients, 35,000 out-patients/year) a pilot study was performed. This had to be done without interrupting routine services. RESULTS After intensive preparations were performed and the hospital-network was completed, within a two year period all radiological functions (mammography excluded), reporting stations and archives were changed to a complete digital workflow. All modalities (provided by 3 different companies) are now connected by DICOM-work lists. The picture-files (4 GB/day) are automatically routed to the work-stations (n = 10), where the reporting and file shows are performed, to the digital archive and to the peripheral viewing-stations (n = 44). The distribution of the digital pictures takes place all over the hospital including the ORs and special units. We accomplished, to connect electronically the report and the image data. The clinical file shows are also performed completely digitally. The access to the data of the deep archive is possible by the dept. of radiology without any manual interaction. The film consumption was reduced to an amount of less than 10%, as compared to the prior PACS situation. Since PACS has been introduced the radiological productivity increased by more than 15% and throughput-time was clearly reduced. CONCLUSIONS The complete digitalisation increases productivity and attractiveness of a hospital-radiology and helps to shorten diagnostic and therapeutic decision-making. The transfer from a conventional to a digital workflow is possible without interrupting the clinical services. Extensive preparations and ongoing assistance of such projects though are clearly needed.
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New measurement of K(+)(e4) decay and the s-pave pi pi-scattering length a(0)(0). PHYSICAL REVIEW LETTERS 2001; 87:221801. [PMID: 11736394 DOI: 10.1103/physrevlett.87.221801] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2001] [Revised: 10/01/2001] [Indexed: 05/23/2023]
Abstract
A sample of 4 x 10(5) events from the decay K(+)-->pi(+)pi(-)e(+)nu(e) (K(e4)) has been collected in experiment E865 at the Brookhaven Alternating Gradient Synchrotron. The analysis of these data yields new measurements of the K(e4) branching ratio [(4.11+/-0.01+/-0.11) x 10(-5)], the s-wave pi pi scattering length [a(0)(0) = 0.216+/-0.013(stat)+/-0.004(syst)+/-0.005(theor)], and the form factors F, G, and H of the hadronic current and their dependence on the invariant pi pi mass.
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Direct observation of interfacial profiles of polymer gels during the phase transition by Raman microimaging. POLYMER 2001. [DOI: 10.1016/s0032-3861(00)00544-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Search for lepton flavor violation in K+ decays into a charged pion and two leptons. PHYSICAL REVIEW LETTERS 2000; 85:2877-2880. [PMID: 11005958 DOI: 10.1103/physrevlett.85.2877] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2000] [Indexed: 05/23/2023]
Abstract
A search for lepton flavor violating decays, K+ --> mu+ mu+ pi-, K+ --> e+ e+ pi-, K+ --> pi+ e+ mu-, K+ --> mu+ e+ pi-, and pi0 --> e+ mu-, was performed using the data collected in Experiment E865 at the Brookhaven Alternating Gradient Synchrotron. No signal was found in any of the decay modes. At the 90% confidence level, the branching ratios are less than 3.0x10(-9), 6.4x10(-10), 5. 2x10(-10), 5.0x10(-10), and 3.4x10(-9), respectively.
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Improved limit on the rate of the decay K+ --> pi(+)&mgr;(+)e(-). PHYSICAL REVIEW LETTERS 2000; 85:2450-2453. [PMID: 10978079 DOI: 10.1103/physrevlett.85.2450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2000] [Indexed: 05/23/2023]
Abstract
We report results of a search for the lepton-family number violating decay K+-->pi(+)&mgr;(+)e(-) from data collected by experiment E865 in 1996 at the Alternating Gradient Synchroton of Brookhaven National Laboratory. We place an upper limit on the branching ratio at 3.9x10(-11) ( 90% C.L.). Together with results based on data collected in 1995 and an earlier experiment, E777, this result establishes a combined 90% confidence level upper limit on the branching ratio at 2.8x10(-11). We also report a new upper limit on the branching ratio for pi(0)-->&mgr;(+)e(-) of 3.8x10(-10) ( 90% C. L.).
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New measurement of the rare decay K+ --> pi(+)&mgr;(+)&mgr;(-). PHYSICAL REVIEW LETTERS 2000; 84:2580-2583. [PMID: 11017274 DOI: 10.1103/physrevlett.84.2580] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/1999] [Indexed: 05/23/2023]
Abstract
More than 400 K+-->pi(+)&mgr;(+)&mgr;(-) events were observed in a rare K+ decay experiment at the Brookhaven Alternating Gradient Synchrotron. Normalized to the K+-->pi(+)pi(+)pi(-) decay, the branching ratio is determined to be [9.22+/-0.60(stat)+/-0. 49(syst)]x10(-8). This branching ratio and the &mgr;&mgr; mass spectrum is in very good agreement with the measurement of the K+-->pi(+)e(+)e(-) decay, but deviates significantly from the previous measurement.
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Fetal epidermal differentiation and barrier development In vivo is accelerated by nuclear hormone receptor activators. J Invest Dermatol 1999; 113:788-95. [PMID: 10571735 DOI: 10.1046/j.1523-1747.1999.00743.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Nuclear receptors which interact with the retinoid X receptor are involved in the regulation of epidermal differentiation and development. We have recently shown that activators of the peroxisome proliferator-activated receptor and of the farnesoid X-activated receptor accelerate epidermal barrier maturation in fetal rat skin in vitro. In this study we asked whether cutaneous development in utero was affected by peroxisome proliferator-activated receptor or farnesoid X-activated receptor activators, or by an activator of another retinoid X receptor partner, liver X receptor. Activators of the peroxisome proliferator-activated receptor (clofibrate or linoleic acid), farnesoid X-activated receptor (farnesol or juvenile hormone III), or liver X receptor (22R-hydroxycholesterol), were injected into the amniotic fluid of fetal rats on gestational day 17. Fetal epidermal barrier function and morphology was assessed on day 19. Whereas vehicle-treated fetal rats displayed no measurable barrier (transepidermal water loss > 10 mg per cm2 per h), a measurable barrier was induced by the intra-amniotic administration of all activators tested (transepidermal water loss range 4.0-8.5 mg per cm2 per h). By light microscopy, control pups lacked a well-defined stratum corneum, whereas a distinct stratum corneum and a thickened stratum granulosum were present in treated pups. By electron microscopy, the extracellular spaces of the stratum corneum in control pups revealed a paucity of mature lamellar unit structures, whereas these structures filled the stratum corneum interstices in treated pups. Additionally, protein and mRNA levels of loricrin and filaggrin, two structural proteins of stratum corneum, were increased in treated epidermis, as were the activities of two lipid catabolic enzymes critical to stratum corneum function, beta-glucocerebrosidase and steroid sulfatase. Finally, peroxisome proliferator-activated receptor-alpha and -delta and liver X receptor-alpha and -beta mRNAs were detected in fetal epidermis by reverse transcriptase-polymerase chain reaction and northern analyses. The presence of these receptors and the ability of their activators to stimulate epidermal barrier and stratum corneum development suggest a physiologic role for peroxisome proliferator-activated receptor and liver X receptor and their endogenous ligands in the regulation of cutaneous development.
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Down-regulation of liver and heart specific fatty acid binding proteins by endotoxin and cytokines in vivo. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1440:118-26. [PMID: 10477831 DOI: 10.1016/s1388-1981(99)00120-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Fatty acid binding proteins (FABPs) are abundantly present in tissues that actively metabolize fatty acids (FA). While their precise physiological function is not known, FABPs have been shown to play a role in the uptake and/or utilization of FA within the cell. FA metabolism is markedly altered during the host response to infection and inflammation. Previous studies have demonstrated that endotoxin or bacterial lipopolysaccharide (LPS) enhances hepatic FA synthesis and re-esterification while inhibiting FA oxidation in liver, heart and muscle. Now, we have examined the in vivo effects of LPS and cytokines on FABPs in liver (L-FABP), heart and muscle (H-FABP). Syrian hamsters were injected with LPS, tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) and the mRNA and protein content for L-FABP and H-FABP were analyzed. 16 h after administration, LPS (100 microg/100 g body weight) produced a 72% decrease in L-FABP mRNA levels in liver and this effect was sustained for 24 h. LPS also produced a 41% decrease in the protein content of L-FABP in liver after 24 h of treatment. TNF-alpha and IL-1beta decreased L-FABP mRNA levels in liver by 30 and 45%, respectively. LPS decreased H-FABP mRNA levels in skeletal muscle by 60% and in heart by 65%. LPS also produced a 49% decrease in H-FABP protein content in muscle. Neither TNF-alpha nor IL-1beta had any significant effect on H-FABP mRNA expression in heart and muscle. Taken together, these results indicate that LPS decreases FABP mRNA and protein levels in liver, heart and muscle, tissues that normally utilize FA as their primary fuel, whereas the inhibitory effect of cytokines is limited to the liver. The LPS-induced decrease in L-FABP and H-FABP may be an additional mechanism contributing to the decrease in FA oxidation that is associated with the host response to infection and inflammation.
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Abstract
Since its birth in 1978, DIOGENE, the hospital information system of Geneva University Hospital has been constantly evolving, with a major change in 1995, when migrating from a centralized to an open distributed architecture. For a few years, the hospital had to face health policy revolution with both economical constraints and opening of the healthcare network. The hospital information system DIOGENE plays a significant role by integrating four axes of knowledge: medico-economical context for better understanding and influencing resources consumption; the whole set of patient reports and documents (reports, encoded summaries, clinical findings, images, lab data, etc.), patient-dependent knowledge, in a vision integrating time and space; external knowledge bases such as Medline (patient-independent knowledge); integration of these patient-dependent and independent knowledge in a case-based reasoning format, providing on the physician desktop all relevant information for helping him to take the most appropriate adequate decision.
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Metabolic adaptation to long term changes in gravity environment. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 1998; 22:273-276. [PMID: 11541405 DOI: 10.1016/s0273-1177(98)80019-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Biochemical analyses of the brain of Cichlid fish larvae, exposed during their very early development for 7 days to an increased acceleration of 3g (hyper-gravity), revealed a decrease in brain nucleoside diphosphate kinase (NDPK) as well as creatine kinase (BB-CK) activity. Using high performance liquid chromatography (HPLC) the concentrations of adenine nucleotides (AMP, ADP, ATP), phospliocreatine (CP), as well as of nicotineamide adenine dinucleotides (NAD, NADP) were analyzed in the brain of hyper-g exposed larvae vs. 1g controls. A slight reduction in the total adenine nucleotides (TAN) as well as the adenylate energy charge (AEC) was found. In parallel a significant increase in the NAD concentration and a corresponding decrease in NADP concentration occurred in larva's hyper-g brains vs. 1 g controls. These results give further evidence for an Influence of gravity on cellular level and furthermore contribute to a clarification of the cellular signal-response chain for gravity perception.
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Activators of the nuclear hormone receptors PPARalpha and FXR accelerate the development of the fetal epidermal permeability barrier. J Clin Invest 1997; 100:705-12. [PMID: 9239419 PMCID: PMC508240 DOI: 10.1172/jci119583] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Members of the superfamily of nuclear hormone receptors which are obligate heterodimeric partners of the retinoid X receptor may be important in epidermal development. Here, we examined the effects of activators of the receptors for vitamin D3 and retinoids, and of the peroxisome proliferator activated receptors (PPARs) and the farnesoid X-activated receptor (FXR), on the development of the fetal epidermal barrier in vitro. Skin explants from gestational day 17 rats (term is 22 d) are unstratified and lack a stratum corneum (SC). After incubation in hormone-free media for 3-4 d, a multilayered SC replete with mature lamellar membranes in the interstices and a functionally competent barrier appear. 9-cis or all-trans retinoic acid, 1,25 dihydroxyvitamin D3, or the PPARgamma ligands prostaglandin J2 or troglitazone did not affect the development of barrier function or epidermal morphology. In contrast, activators of the PPARalpha, oleic acid, linoleic acid, and clofibrate, accelerated epidermal development, resulting in mature lamellar membranes, a multilayered SC, and a competent barrier after 2 d of incubation. The FXR activators, all-trans farnesol and juvenile hormone III, also accelerated epidermal barrier development. Activities of beta-glucocerebrosidase and steroid sulfatase, enzymes previously linked to barrier maturation, also increased after treatment with PPARalpha and FXR activators. In contrast, isoprenoids, such as nerolidol, cis-farnesol, or geranylgeraniol, or metabolites in the cholesterol pathway, such as mevalonate, squalene, or 25-hydroxycholesterol, did not alter barrier development. Finally, additive effects were observed in explants incubated with clofibrate and farnesol together in suboptimal concentrations which alone did not affect barrier development. These data indicate a putative physiologic role for PPARalpha and FXR in epidermal barrier development.
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Apparent protection from instability of repeat sequences in cancer-related genes in replication error positive gastrointestinal cancers. Oncogene 1997; 14:2613-8. [PMID: 9191061 DOI: 10.1038/sj.onc.1201094] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Genomic instability at simple repeated sequences has been observed in various types of human cancers and is considered an important mechanism in tumorigenesis. Alterations at microsatellite loci have been reported scattered throughout the genome. Recently, the transforming growth factor-beta receptor type II (TGF-beta RII) and the insulin-like growth factor II receptor (IGF-IIR) genes were shown to have inactivating mutations within coding microsatellite sequences. The demonstration of mutations in two growth regulatory genes supports the idea that other regulatory genes with repeat sequences may also be targets in tumours with defective mismatch repair. We examined genes involved in tumour suppression, cell adhesion and cell cycle regulation for mutations at small repeat sequences in replication error positive gastrointestinal cancers. Several polymorphisms were found which exhibited instability, but no other instability was present in the regions examined.
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Comparison of early IgM-enriched immunoglobulin vs polyvalent IgG administration in score-identified postcardiac surgical patients at high risk for sepsis. Chest 1997; 111:419-26. [PMID: 9041991 DOI: 10.1378/chest.111.2.419] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
STUDY OBJECTIVE To address the relevance of the IgM component in polyvalent immunoglobulins in sepsis treatment by comparison of the clinical course under polyvalent IgG vs IgGMA therapy in postcardiac surgical patients at high risk for sepsis and to reassess the prognostic validity of sequential changes in acute physiology and chronic health evaluation (APACHE II) scores during treatment. DESIGN Prospective, randomized clinical trial. SETTING Cardiac surgical ICU in a university hospital. PATIENTS Among 870 consecutive patients after elective open-heart surgery, 29 (3.3%) met the previously validated high-risk criterion (APACHE II score > or = 24 on the first postoperative day) with a mean APACHE II score-predicted mortality risk of 63%. INTERVENTIONS In addition to standard therapy, 27 of these patients were randomized to receive commercially available IV IgG (Polyglobin N, n = 14, total dosage: 18 mL/kg) or IgGMA (Pentaglobin, n = 13, total dosage: 15 mL/kg). MEASUREMENTS AND RESULTS The two groups were comparable in baseline disease severity and concurrent therapy. The extent of score-quantified improvement in disease severity during treatment was similar in both groups (mean fall in APACHE II scores within 4 days; IgG, -6.9; IgGMA, -5.2), as were score-defined improvement rates (rate of patients with score decrease > or = 7 within 4 days: IgG, 57%; IgGMA, 54%) and in-hospital mortality (IgG, 29%; IgGMA, 31%) (all p = NS). There was a strong association between the decrease over time in APACHE II scores during therapy and prognosis (mortality rates in patients with vs without score-assessed improvement: 0% vs 67%, p = 0.0002). CONCLUSIONS IgG and IgGMA were associated with a comparable improvement in disease severity in score-identified postcardiac surgical patients at high risk for sepsis. Given the design as an efficacy rather than an equivalence study, this hypothesis derived from our results needs independent validation in larger trials. Sequential APACHE II score changes were reconfirmed as a prognostically valid quantitative measure of disease progress during sepsis therapy.
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Abstract
BACKGROUND & AIMS Numerous gastrointestinal tumors, notably sporadic and ulcerative colitis (UC)-associated colorectal carcinomas and dysplasias, gastric cancers, and esophageal carcinomas, manifest microsatellite instability. Recently, a transforming growth factor beta 1 type II receptor (TGF-beta 1RII) mutation in a coding microsatellite was described in colorectal carcinomas showing instability. One hundred thirty-eight human neoplasms (61 UC-associated, 35 gastric, 26 esophageal, and 16 sporadic colorectal) were evaluated for this TGF-beta 1RII mutation. METHODS Whether instability was present at other chromosomal loci in these lesions was determined. In lesions manifesting or lacking instability, the TGF-beta 1RII coding region polydeoxyadenine (poly A) microsatellite tract was polymerase chain reaction amplified with 32P-labeled deoxycytidine triphosphate. Polymerase chain reaction products were electrophoresed on denaturing gels and exposed to radiographic film. RESULTS Three of 18 UC specimens with instability at other chromosomal loci (17%) showed TGF-beta 1RII poly A tract mutation, including 2 cancers and 1 dysplasia; moreover, 2% of UC specimens without instability (1 of 43) (1 cancer), 81% of unstable sporadic colorectal cancers (13 of 16), and none of the 61 stable or unstable gastric or esophageal cancers contained TGF-beta 1RII mutations. CONCLUSIONS Mutational inactivation of the poly A microsatellite tract within TGF-beta 1RII occurs early and in a subset of unstable UC neoplasms and commonly in sporadic colorectal cancers but may be rare in unstable gastric and esophageal tumors.
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Infrequent DPC4 gene mutation in esophageal cancer, gastric cancer and ulcerative colitis-associated neoplasms. Oncogene 1996; 13:2459-62. [PMID: 8957088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Homozygously Deleted in Pancreatic Cancer 4 (DPC4), a recently identified candidate tumor suppressor gene, was previously shown to be altered in human pancreatic cancers. We examined DPC4 mutation in 30 examples of three other types of gastrointestinal malignancy: 10 esophageal cancers, 10 gastric cancers and 10 colorectal cancers occurring in the preneoplastic condition, ulcerative colitis. The entire coding region of DPC4 (including all 11 exons) was analysed by either direct sequencing of PCR product or the in vitro synthesized protein assay. No coding region mutations of DPC4 were found in any of the samples examined. Our results suggest that inactivation of DPC4 may not be important in the majority of these types of gastrointestinal cancer.
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Microsatellite instability in the insulin-like growth factor II receptor gene in gastrointestinal tumours. Nat Genet 1996; 14:255-7. [PMID: 8896552 DOI: 10.1038/ng1196-255] [Citation(s) in RCA: 326] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Alterations of transforming growth factor-beta 1 receptor type II occur in ulcerative colitis-associated carcinomas, sporadic colorectal neoplasms, and esophageal carcinomas, but not in gastric neoplasms. Hum Cell 1996; 9:229-36. [PMID: 9183654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND & AIMS Gastric cancers, sporadic colorectal cancers, and ulcerative colitis (UC)-associated colorectal carcinomas and dysplasias manifest microsatellite instability (MI); however, esophageal carcinomas rarely exhibit MI. Recently, a transforming growth factor-beta 1 type II receptor (TGF-beta 1RII) mutation in a coding microsatellite was described in primary colorectal carcinomas demonstrating MI. No previous studies of TGF-beta 1RII have addressed mechanisms of inactivation other than MI in human tumors; furthermore, MI-negative tumors have not been examined for TGF-beta 1RII mutation. We evaluated 138 primary human neoplasms for mutation in the poly-A microsatellite tract of TGF-beta 1RII. Additionally, a group of esophageal tumors was evaluated for the expression of TGF-beta 1RII messenger RNA (mRNA). METHODS First, we determined whether MI was present at other chromosomal loci in these lesions. The poly-deoxyadenine (poly-A) microsatellite tract within the TGF-beta 1RII coding region was then PCR-amplified. In a group of MI-negative esophageal tumors, RT-PCR was performed to determine the expression of TGF-beta 1RII mRNA. RESULTS Among 17 MI+ UC specimens, 3 (18%) demonstrated TGF-beta 1RII poly-A tract mutation (2 cancers and 1 dysplasia), while 2 (4%) of 44 MI-negative UC specimens (1 dysplasia and 1 tumor), and 13 (81%) of 16 MI+ sporadic colorectal cancers, contained TGF-beta 1RII poly-A mutation. No gastric or esophageal tumors contained TGF-beta 1RII mutation. Among 21 MI-negative esophageal carcinomas. 6 cases (28.5%) had TGF-beta 1RII transcripts that were low or undetectable by RT-PCR. CONCLUSIONS Mutation within the poly-A microsatellite tract of TGF-beta 1RII occurs early in a subset of UC-neoplasms and commonly in sporadic colorectal cancers, but may be rare in MI+ gastric tumors. Diminished expression of TGF-beta 1RII mRNA in esophageal tumors suggests that mechanisms of inactivation in this gene other than MI play a role in esophageal carcinogenesis.
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Early prediction of outcome in score-identified, postcardiac surgical patients at high risk for sepsis, using soluble tumor necrosis factor receptor-p55 concentrations. Crit Care Med 1996; 24:596-600. [PMID: 8612409 DOI: 10.1097/00003246-199604000-00008] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To investigate the prognostic value of increased serum concentrations of soluble tumor necrosis factor (TNF) receptors in patients at high risk for sepsis. DESIGN Prospective study. SETTING Cardiac surgical intensive care unit in a University Hospital. PATIENTS Those 27 of 870 consecutive postcardiac surgical patients who met a previously validated high-risk criterion for imminent sepsis (Acute Physiology and Chronic Health Evaluation II [APACHE II] score of > or = 24 on the first postoperative day [day 1]). In this population, systemic inflammatory response syndrome was present in 96% of the patients and the in-hospital mortality rate was 30%. In addition, ten postcardiac surgical patients with an uncomplicated course (mortality rate 0%) were studied for comparison. INTERVENTIONS Blood sampling for measurements of serum concentrations of TNF and soluble TNF receptors 55 kilodalton (TNF receptor-p55) and 75 kilodalton (TNF receptor-p75) on days 1, 2, 3, and 5. MEASUREMENTS AND MAIN RESULTS Compared with the ten patients with an uncomplicated course (group A), the high-risk patients had significantly higher baseline (day 1) serum concentrations of soluble TNF receptor-p55 (9.2 vs. 4.2 ng/mL) and soluble TNF receptor-p75 (9.2 vs. 5.5 ng/mL). These high-risk patients could be further differentiated into two subgroups: one (B) with a prompt decrease in APACHE II score and a good prognosis (mortality rate 0%) and another (C) with a persisting high risk of sepsis and mortality rate (40%, p < .05). Although baseline APACHE II score was similar in both high-risk subgroups, soluble TNF receptor-p55 concentrations were significantly higher in subgroup C compared with subgroup B already at baseline (10.7 vs. 4.7 ng/mL). The receiver operating characteristic curve for subgroup classification by soluble TNF receptor-p55 was in a discriminating position with an area (0.773 +/- 0.096), confirming soluble TNF receptor-p55 as a predictor of mortality. TNF and soluble TNF receptor-p75 concentrations were less predictive at baseline. CONCLUSIONS This study suggest that increased soluble TNF receptor-p55 concentrations in the serum of postcardiac surgical patients allow earlier prognostication of subsequent hospital course than APACHE II scores alone. This study further suggests that the combination of physiologic scores and cytokine receptor measurements could improve the predictive power of early postoperative risk stratification.
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Bedeutung erhöhter TNF-Rezeptorspiegel bei herzchirurgischen Risikopatienten. Transfus Med Hemother 1996. [DOI: 10.1159/000223345] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Wir untersuchten prospektiv den prognostischen Wert erhöhter Serumkon-zentrationen der löslichen Tumor-Nekrose-Faktor-Rezeptoren (sTNFR) bei imminenter Sepsis. Die Studienpopulation bestand aus jenen 27 von insgesamt 870 konsekutiven postkardiochirurgischen Patienten, welche ein zuvor validiertes Hochrisikokriterium für eine imminente Sepsis aufwiesen [APACHE-II-Score (APII) > 24 am 1. postoperativen Tag (Tag 1)]. In dieser Population lag ein systemisches Inflammations-Reaktions-Syndrom (SIRS) bei 96% der Patienten vor, die Krankenhausletalität betrug 30%. Zusätzlich wurden 10 postkardiochirurgische Patienten mit unkompliziertem Verlauf (Letalität: 0%) zum Vergleich untersucht. Verglichen mit den 10 Patienten mit unkompliziertem Verlauf (Gruppe A), wiesen die Hochri-sikopatienten signifikant höhere Ausgangswerte (Tag 1) für sTNFR-p55 (9,2 vs. 4,2ng/ml) und sTNFR-p75 (9,2 vs. 5,5 ng/ml) auf. Für den vorgefundenen Kreatinin-Wertebereich (Maximalwert: 2,48 mg/dl) fanden wir keine Korrelation zwischen Kreatinin und sTNFR-p55 (r=0,10) bzw. sTNFR-p75 (r=0,19). Die Hochrisikopatienten konnten in 2 Subgruppen differenziert werden: in die Subgruppe B mit einem prompten Abfall des APII und einer guten Prognose (Letalität: 0%) und Subgruppe C mit persistierend hohem Risiko und hoher Letalität (40%, p < 0,05). Trotz vergleichbarer APII-Ausgangswerte in beiden Hochrisikosubgruppen wa-ren die sTNFR-p55-Spiegel in der Subgruppe C im Vergleich zu B bereits am Tag 1 signifikant erhöht (10,7 vs. 4,7 ng/ml). Die ROC-Kurve für die Subgruppenklassifikation mittels sTNFR-p55 zeigte bereits am Tag 1 eine gute Trennschärfe mit einer Fläche von 0,773+0,096, was den Parameter als Prognoseprädikator bestätigte. Die sTNFR-p75-Ausgangskonzentratio-nen wiesen eine geringere prädiktive Wertigkeit auf. Zusammengefaβt weist unsere Studie darauf hin, daβ erhöhte sTNFR-p55-Serumspiegel bei postkardiochirurgischen Patienten frühzeitiger den Schweregrad von Krankheitsverlauf und Prognose anzeigen als APII-Scores allein. Dies spricht dafür, daβ durch die Kombination von physiolo-gischen Scores und Zytokinrezeptormessungen die prädiktive Wertigkeit einer frühzeitigen postoperativen Risikostratifizierung erhöht werden kann.
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Influence of altered gravity on brain cellular energy and plasma membrane metabolism of developing lower aquatic vertebrates. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 1996; 17:125-128. [PMID: 11538605 DOI: 10.1016/0273-1177(95)00624-n] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Biochemical analyses of the brain of cichlid fish larvae, exposed for 7 days to increased acceleration of 3g (hyper-g), revealed an increase in energy availability (succinate dehydrogenase activity, SDH), and in mitochondrial energy transformation (creatine kinase, Mia-CK), but no changes in an energy consumptive process (high-affinity Ca(2+)-ATPase). Brain glucose-6-phosphate dehydrogenase (G6PDH) of developing fish was previously found to be increased after hyper-g exposure. Three respectively 5 hours thereafter dramatic fluctuations in enzyme activity were registered. Analysing the cytosolic or plasma membrane-located brain creatine kinase (BB-CK) of clawed toad larvae after long-term hyper-g exposure a significant increase in enzyme activity was demonstrated, whereas the activity of a high affinity Ca(2+)-ATPase remained unaffected.
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Development and altered gravity dependent changes in glucose-6-phosphate dehydrogenase activity in the brain of the cichlid fish Oreochromis mossambicus. Neurochem Int 1995; 26:579-85. [PMID: 7670361 DOI: 10.1016/0197-0186(94)00176-u] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Glucose-6-phosphate dehydrogenase activity was studied in the brain of the cichlid fish Oreochromis mossambicus during early ontogenetic development. In general a slight but continuous decrease in enzyme activity was found (9.5 +/- 0.5 nmol substrate cleaved per mg protein and per min at developmental stage 13 [= 1 day post hatch at 28 degrees C] to a value of 7.9 +/- 0.6 in adult brain). In order to investigate the possible influence of altered gravity during early ontogenetic brain development, fish larvae were exposed to an increased acceleration of three times earth gravity (3 g) or to functional weightlessness in a fast-rotating clinostat for 7 days. A significant increase of brain G6PDH activity of approx. 15% was found after exposure to hyper gravity, whereas a significant decrease of the enzyme activity, approximately 10%, was detected following functional weightlessness in respect to the corresponding 1 g controls. Analyses concerning the regain of normal control enzyme activity of the larvae revealed dramatic fluctuations within the first 5 h after exposure to an increased acceleration of 3 g. Thereafter, between day 1 and day 3 after exposure, brain glucose-6-phosphate dehydrogenase decreased slowly. At day 3 after exposure no further differences of the hyper-g larvae compared to the controls were found. Only slight changes in total brain glucose-6-phosphate dehydrogenase activity occur during ontogenetic development of cichlid fish. This suggests that a more or less constant enzyme activity is important during brain development, but is reacting very sensitively to changes in the environmental factor gravity.
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Early sepsis treatment with immunoglobulins after cardiac surgery in score-identified high-risk patients. Chest 1994; 105:76-82. [PMID: 8275790 DOI: 10.1378/chest.105.1.76] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
In patients at risk for sepsis after cardiac surgery, the efficacy of intravenous immunoglobulin (Ig) treatment was compared with a historical control population, equivalent in patient characteristics and disease severity. Using APACHE II scores, especially in the high-risk group (IgG), we could discriminate between low-risk patients (score < 19; mortality 1 percent) and the small groups at risk (score 19 to 23) and high risk (score > or = 24) with a significantly higher mortality (14 percent and 76 percent, respectively) [corrected]. Subsequently, among 1,341 consecutive patients we prospectively identified and treated (IgG n = 41 IgGMA: n = 25) these at-risk groups. In contrast to controls (risk: n = 21; high-risk; n = 21), we found a marked fall in APACHE II scores, especially in the high-risk group (IgG, n = 26: p < 0.05; IgGMA, n = 13: p = 0.08) [corrected]. In this group, Ig therapy produced higher (p < 0.05) response rates (score decrease 7 within 4 days: IgG: 54 percent, IgGMA: 62 percent; controls: 19 percent) and reduced mortality (IgG: 46 percent, IgGMA: 46 percent; controls: 76 percent), statistically significant (p < 0.05) for Ig treatment overall. Thus, early Ig treatment improves disease severity and may improve prognosis in prospectively score-identified high-risk postcardiac surgical patients.
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Comparison of 20 exclusive reactions at large t. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1994; 49:58-78. [PMID: 10016744 DOI: 10.1103/physrevd.49.58] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Behavioural and biochemical investigations of the influence of altered gravity on the CNS of aquatic vertebrates during ontogeny. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 1994; 14:309-312. [PMID: 11537932 DOI: 10.1016/0273-1177(94)90416-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Quantitative data are presented on the influences of hyper-gravity (3 +/- 1g) and of simulated weightlessness (approximately 0g) during early ontogeny of cichlid fish (Oreochromis mossambicus) and clawed toad (Xenopus laevis, Daudin) demonstrating changes in the swimming behaviour and the brain energy and plasma membrane metabolism. After return to 1g conditions, hyper-g reared fish and toads express the well known "loop-swimming" behaviour. By means of a computer based video analyzing system different types of swimming movements and velocities were quantitatively determined. Analyses of the brain energy and plasma-membrane metabolism of hyper-g fish larvae demonstrated an increase in energy availability (glucose 6Pi dehydrogenase, G-6P-DH), a decrease of cellular energy transformation (creatine kinase activity, CK) but no changes in energy consumptive processes (e.g. ATPases) and cytochrome oxidase activity (Cyt.-Ox). In contrast hypo-g fish larvae showed a slight increase in brain CK activity. In addition, unlike 1g controls, hyper-g fish larvae showed pronounced variations in the composition (=polarity) of sialoglycosphingolipids (=gangliosides), typical constituents of the nerve cell membranes, and a slight increase in the activity of sialidase, the enzyme responsible for ganglioside degradation.
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Crystal structure of 3-cyclohexyl-2-trifluoromethyl- 6-methyl-2-trimethylsilyloxy-l-aza-3- phospha-cyclohex-5-en-4-one, C 15H 25F 3NO 2PSi. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.206.12.292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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[Early immunoglobulin therapy in high risk patients for infection after heart surgery]. INFUSIONSTHERAPIE UND TRANSFUSIONSMEDIZIN 1993; 20 Suppl 1:35-40; discussion 41. [PMID: 8499749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The efficacy of early supplemental intravenous immunoglobulin G (ivIgG) treatment was investigated in 41 patients at risk for sepsis following cardiac surgery (APACHE II score > or = 19 on the 1st postoperative day). The ivIgG preparation (Psomaglobin N) was chosen because of its reported high antibody titers and effectiveness in animal models against gram-positive microorganisms, preponderant as infective agents after heart surgery. The control group consisted of a historical cohort of 42 cardiac surgical patients of comparable pretreatment disease and sepsis severity. Following ivIgG therapy on the 1st and 2nd days after surgery, we found a marked improvement in disease severity (fall in APACHE II scores) in contrast to the control patients, especially evident in the high-risk group of patients with an APACHE II score > or = 24 on the 1st postoperative day (n = 26). In this group, ivIgG therapy led to higher (p < 0.05) response rates defined as a score decrease > or = 7 within 4 days (ivIgG-treated patients 54%, controls 19%), and a reduction in mortality (ivIgG-treated patients 46%, controls 76%; p = 0.08). Given the good comparability of the study groups, the results of this trial indicate, despite its nonrandomized design, that early supplemental ivIgG treatment seems to decrease disease severity and probably also improve the prognosis in APACHE II score identified high-risk patients after cardiac surgery.
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Brain creatine kinase activity during ontogeny of the cichlid fish oreochromis mossambicus and the clawed toad Xenopus laevis, influence of gravity? Neurochem Int 1993; 22:405-11. [PMID: 8457775 DOI: 10.1016/0197-0186(93)90022-w] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The development of creatine kinase (CK) activity was studied in the brain of cichlid fish and clawed toads. The activity of CK in the whole brain of the fish decreases immediately after hatching (stage 6) from values of about 135 nmol substrate cleaved/mg protein/min to a value of about 105 at stage 8 (5 days post hatch at 20 degrees C). With the exception of a significant peak (125 nmol) between stages 9 and 10 (7 and 9 days respectively, post hatch at 20 degrees C) and a small intermediate peak at stages 12 and 13 (about 10 days post hatch at 20 degrees C) a constant level of about 100 nmol cleaved substrate is maintained until maturity. In contrast, CK activity was determined to be 3-fold higher in the whole brain of the clawed toad. With the exception of two significant peaks at stages 47 and 49 (5 and 12 days respectively, post fertilization at 23 degrees C) a value of about 360 nmol was found during larval development and metamorphosis, as well as in the adult brain. In investigating the possible influence of gravity on CK activity during early ontogeny of the brain both animal species were exposed to hyper-gravity (3 +/- 1 g) for 7 days. A significant decrease of total CK activity of 20% was found in the fish brain and of about 5% in the toad.(ABSTRACT TRUNCATED AT 250 WORDS)
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Frühzeitige lmmunglobulintherapie bei Hochrisikopatienten für Sepsis nach Herzchirurgie. Transfus Med Hemother 1993. [DOI: 10.1159/000222887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Bei 41 Sepsisrisikopatienten nach herzchirurgischen Eingriffen (APACHE-II-Score ≥ 19 am 1. postoperativen Tag) wurde die Wirkung einer frühzeitigen additiven The-rapie mit intravenös verabreichtem Immunglobulin G (ivIgG) untersucht. Das ivIgG-Präparat (Psomaglobin® N) wurde gewählt wegen des hohen Antikörpertiters sowie wegen der im Tiermodell nachgewiesenen Wirksamkeit gegen grampositive Mikroorganismen, welche als infektiöse Keime nach Herzchirurgie überwiegen. Die Kontrollgruppe umfaβte ein historisches Kollektiv von 42 Patienten nach Herzchirurgie mit vergleichbarem initialem Krankheits- und Sepsisschweregrad. Nach der ivIgG-Therapie am 1. und am 2. postoperativen Tag fand sich im Gegensatz zu den Kontrollpatienten eine deutliche Besserung des Krankheitsschweregrades (Abfall des APACHE-II-Scores), welche in der Hochrisikogruppe (Patienten mit einem APACHE-II-Score& > 24 am 1. postoperativen Tag, n = 26) besonders ausgeprägt war. In dieser Gruppe führte die ivIgG-Therapie zu höheren (p < 0,05) «Response»-Raten (definiert als Score-Abfall& > 7 innerhalb von 4 Tagen; ivIgG 54%, Kontrollen 19%) und zu einer Senkung der Letalität (ivIgG 46% Kontrollen 76%; p = 0,08). Angesichts der Vergleichbarkeit der Studiengruppen weisen die Ergebnisse dieser Studie – trotz der Einschränkung durch das nichtrandomisierte Studiendesign – darauf hin, daβ eine frühzeitige additive ivIgG-Therapie zu einer Besserung des Krankheitsschweregrades und wahrscheinlich auch der Prognose von – anhand des APACHE-II-Scores identifizierten – Sepsishochrisikopatienten nach Herzchirurgie führt.
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Effect of dexamethasone on proliferating osteoblasts: inhibition of prostaglandin E2 synthesis, DNA synthesis, and alterations in actin cytoskeleton. Exp Cell Res 1992; 203:150-6. [PMID: 1426038 DOI: 10.1016/0014-4827(92)90050-i] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Elevated levels of glucocorticoids caused by disease (Cushing's syndrome) or therapeutic treatment of asthma are known to cause osteoporosis. Space flight, an environmental condition, is known to cause a rise in endogenous cortisols accompanied by a significant loss of bone and calcium. Long-term space inhabitants have lost up to 18% of weight bearing bone during long-term flight. This study demonstrates that elevated concentrations of glucocorticoids lower the endogenous production of PGE2 and interfere with osteoblast proliferation. Osteoblasts grown with dexamethasone had significantly lower DNA synthesis and endogenous synthesis of PGE2. Addition of exogenous dmPGE2 to the dexamethasone growth-inhibited cells stimulated DNA synthesis over twofold. In synchronous control cultures, we found that endogenous prostaglandin synthesis increased in late G1, preceding S-phase DNA synthesis by several hours. The addition of exogenous dexamethasone to synchronous cultures resulted in a significant decrease in the prostaglandin synthesis followed by a significant decrease in DNA synthesis in parallel cultures. Further, dexamethasone caused the actin cytoskeleton to collapse and the cell morphology to become rounded and spindle shaped. Addition of exogenous PGE2 to the dexamethasone-treated osteoblasts caused recovery of the actin architecture and phenotype. These data support the hypothesis that the glucocorticoid-mediated decrease in prostaglandin synthesis may be a contributing factor in the reduced bone quality and trabecular bone formation seen in glucocorticoid-induced osteoporosis.
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Brain Ca2+/Mg(2+)-ATPase activity and seasonal adaptation of the Djungarian dwarf hamster Phodopus sungorus. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A, COMPARATIVE PHYSIOLOGY 1991; 100:937-41. [PMID: 1685389 DOI: 10.1016/0300-9629(91)90318-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
1. Of three sets of Djungarian dwarf hamster, two groups were raised during winter under greatly differing circumstances. One winter group was raised within a climate controlled cage in which the ambient temperature was maintained at 22 degrees C and whereby conditions of light vs darkness were maintained in a constant 12 hr cycle. The second winter group was raised out of doors whereby the hamsters were subjected to prevailing seasonal environmental conditions. A third group was studied under summer conditions, as well. Ca(2+)-, Mg(2+)- and (Ca2+/Mg2+)-ATPase activity was analysed in cellular (= total homogenate) and subcellular fractions (P1-, synaptosomal fraction, synaptic membranes) from cortex, cerebellum and basal brain. 2. The data obtained indicate similar ATPase activity in the cortical homogenates of the winter indoor and summer hamsters. 3. Winter outdoor animals experiencing normal torpidity, however, exhibited reduced ATPase activity by about 50%. 4. Cortical subcellular fractions yielded different results: both the winter and the summer groups showed high ATPase activity in the synaptosomal and synaptic membrane fractions. 5. In the total cerebellar homogenate, the hamsters raised under summer and winter conditions showed the greatest enzyme activity, although less activity was seen in the subcellular fractions. 6. The ATPase activity in the basal brain was found to be nearly identical in all three hamster groups.
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