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Patient-derived organoids and orthotopic xenografts of primary and recurrent gliomas represent relevant patient avatars for precision oncology. Acta Neuropathol 2020; 140:919-949. [PMID: 33009951 PMCID: PMC7666297 DOI: 10.1007/s00401-020-02226-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/11/2020] [Accepted: 09/12/2020] [Indexed: 11/29/2022]
Abstract
Patient-based cancer models are essential tools for studying tumor biology and for the assessment of drug responses in a translational context. We report the establishment a large cohort of unique organoids and patient-derived orthotopic xenografts (PDOX) of various glioma subtypes, including gliomas with mutations in IDH1, and paired longitudinal PDOX from primary and recurrent tumors of the same patient. We show that glioma PDOXs enable long-term propagation of patient tumors and represent clinically relevant patient avatars that retain histopathological, genetic, epigenetic, and transcriptomic features of parental tumors. We find no evidence of mouse-specific clonal evolution in glioma PDOXs. Our cohort captures individual molecular genotypes for precision medicine including mutations in IDH1, ATRX, TP53, MDM2/4, amplification of EGFR, PDGFRA, MET, CDK4/6, MDM2/4, and deletion of CDKN2A/B, PTCH, and PTEN. Matched longitudinal PDOX recapitulate the limited genetic evolution of gliomas observed in patients following treatment. At the histological level, we observe increased vascularization in the rat host as compared to mice. PDOX-derived standardized glioma organoids are amenable to high-throughput drug screens that can be validated in mice. We show clinically relevant responses to temozolomide (TMZ) and to targeted treatments, such as EGFR and CDK4/6 inhibitors in (epi)genetically defined subgroups, according to MGMT promoter and EGFR/CDK status, respectively. Dianhydrogalactitol (VAL-083), a promising bifunctional alkylating agent in the current clinical trial, displayed high therapeutic efficacy, and was able to overcome TMZ resistance in glioblastoma. Our work underscores the clinical relevance of glioma organoids and PDOX models for translational research and personalized treatment studies and represents a unique publicly available resource for precision oncology.
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Specific bioactive collagen peptides (PETAGILE®) as supplement for horses with osteoarthritis: A two-centred study. J Anim Physiol Anim Nutr (Berl) 2018; 102 Suppl 1:16-23. [DOI: 10.1111/jpn.12863] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 11/09/2017] [Indexed: 12/22/2022]
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A comparative assessment of different experiments on buoyancy driven mixing processes by means of CFD. ANN NUCL ENERGY 2016. [DOI: 10.1016/j.anucene.2015.12.032] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Ektope Ureterenmündungen in den Harntrakt und Nierendystopie beim Hund Zwei Beiträge zur Kasuistik. ACTA ACUST UNITED AC 2010. [DOI: 10.1111/j.1439-0442.1974.tb01095.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abstract
REASONS FOR PERFORMING STUDY Aortoiliac thrombosis (AIT) is a progressive vascular disease characterised by an exercise-induced hindlimb lameness. After developing a surgical technique, a follow-up study was required. OBJECTIVES To assess the surgical results of a surgical thrombectomy in horses with AIT, a chronic arterial occlusive disease of the aorta and its caudal arteries. METHODS Seventeen cases showed the typical signs of AIT and diagnosis was confirmed by Doppler-ultrasonography. Average age of the horses was 12 years. Seven stallions, 6 mares and 4 geldings were included. RESULTS The thrombus was located in the left hindlimb (5 cases), the right hindlimb (9 cases) or in both hindlimbs (3 cases). Two cases were operated on both limbs with a few days between surgeries. Nine (53%) horses regained their athletic performance and 2 horses were able to work for at least 30 min without complaint, instead of the initial 5 min prior to surgery. During surgery one horse had to be subjected to euthanasia because the thrombus was too tightly attached to the arterial wall and could not be removed. Two horses were subjected to euthanasia post operatively due to severe myopathy and one due to a femoral fracture during recovery. Two reocclusions of the treated artery occurred 4 months after surgical intervention: one horse was reoperated and, due to the extent of the thrombus and quality of the arterial wall, the horse was subjected to euthanasia; the other horse was subjected to euthanasia without a second surgery. A severe complication was the appearance of AIT in the contralateral limb after surgery as result of occlusion caused by an embolus loosened by the procedure. Post anaesthetic myopathy was seen in 4 (24%) of the cases and could be so severe that euthanasia had to be considered. CONCLUSION AND POTENTIAL RELEVANCE Surgical intervention by means of a thrombectomy in horses with AIT should be considered; 65% of the horses regained athletic activity and 53% of the operated horses in this study performed at their previous level. Adequate padding, correct positioning, prevention of intraoperative hypotension and keeping surgery time as short as possible, are important parameters to prevent post operative myopathy.
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Open issues in the applicability of recombiner experiments and modelling to reactor simulations. PROGRESS IN NUCLEAR ENERGY 2010. [DOI: 10.1016/j.pnucene.2009.09.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Evaluation of scintigraphic quotients concerning regions of interest at the sesamoid bone and the insertion of the deep digital flexor tendon in horses with palmar foot pain. PFERDEHEILKUNDE 2010. [DOI: 10.21836/pem20100308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Magnetic Resonance Imaging of the Deep Digital Flexor Tendon in the equine foot. PFERDEHEILKUNDE 2010. [DOI: 10.21836/pem20100305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zur Beurteilung des Elektroencephalogramms bei gesunden und psychisch kranken oder abnormen Kindern. Eur Neurol 2008. [DOI: 10.1159/000139702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Transendoscopic implant injection therapy of soft palate and laryngeal diseases in horses – Part 2: Complication post laryngoplasty. PFERDEHEILKUNDE 2003. [DOI: 10.21836/pem20030103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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11
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Cryo electron microscopy shows that myosin switch 1 opens on strong binding to actin. Acta Crystallogr A 2002. [DOI: 10.1107/s010876730208649x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Therapy of an endobronchial neoplasm in an Arabian mare. PFERDEHEILKUNDE 2002. [DOI: 10.21836/pem20020104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Development of a new aerosol delivery system for systemic pulmonary delivery in anaesthetized and orotracheal intubated rats. Lab Anim 2001; 35:261-70. [PMID: 11459412 DOI: 10.1258/0023677011911589] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Over the last decade, the systemic absorption of a broad range of therapeutics after pulmonary application has been demonstrated in animals as well as in humans. The most common method used in the laboratory is the intratracheal instillation of drugs in solution. This method is, however, unsatisfactory, because of discrepancies in particle distribution, clearance, kind of injury and bioavailability between instillation and inhalative application. On the other hand, a precise determination of the amount of drug applied by aerosol, and of the aerosol volume retained within the lungs is rather difficult, and is not possible for use with small animals such as mice or rats. We describe a system which allows the delivery of aerosols directly into the animal's lungs, and calculation of the amount of drug retained in the lungs. Our system was tested in vitro and in vivo and was shown to allow precise and efficient pharmacokinetic and toxicological studies to be carried out.
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Abstract
PURPOSE To study the pulmonary absorption and tolerability of various formulations of the decapeptide cetrorelix acetate in rats by a new aerosol delivery system (ASTA-ADS) for intratracheal application. METHODS Using the ASTA-ADS, cetrorelix liquid formulations (aqueous solutions for ultrasonic nebulization) were firstly selected and subsequently delivered as nebulized aerosol to orotracheally cannulated rats. The pharmacologic effect (decrease of testosterone serum level) of four cetrorelix formulations was determined in rats by enzyme linked immunosorbant assay, and pharmacokinetic data were determined after measurement of cetrorelix serum level by radioimmunoassay. Histological examination of the lung was performed at the end of the experiments, and in a supplementary experiment the respiratory parameters (resistance and compliance) of rats were monitored by a validated pulmonary monitoring system during the aerosol application of the same formulations. RESULTS After an exposure time of 5 min, the applied formulations reduced the testosterone concentration in serum to subnormal levels (< or =1 ng/ml) over a period of 24 h. Comparing the plasma concentration after intratracheal aerosolization with data of intravenous administration, the mean calculated bioavailabilities for the four formulations using the corrected dose (delivered--exhaled amount) were between 48.4 +/- 27.0% and 77.4 +/- 44.0%. The histologic examination of the lungs revealed different tolerability of the various tested formulations ranging from locally intolerable to well tolerated. The measurement of the lung function parameters did not reveal any compound or formulation related changes. CONCLUSIONS Our studies show that cetrorelix can be effectively administered as aerosol and that intratracheal aerosolization via the ASTA-ADS provides results that are well comparable to other application routes, as demonstrated by statistical comparison of the newly obtained data with previous results from intratracheal instillation of cetrorelix solutions in rats.
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Abstract
Actively sensitized Brown Norway rats and guinea pig are useful species for studying drug effects on symptoms of experimental rhinitis. Even if not all symptoms of human rhinitis can be induced and detected in the same animal species, the predictablity of methods generally used is well acceptable. In the present review, advantages and disadvantages of experimental methods of rhinitis will be discussed.
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Disposition and metabolism of cetrorelix, a potent luteinizing hormone-releasing hormone antagonist, in rats and dogs. Drug Metab Dispos 2000; 28:10-20. [PMID: 10611134] [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
Disposition and metabolism of cetrorelix was studied in intact and bile duct-cannulated rats and dogs after s.c. injection. An s.c. dose of 0.1 mg/kg [(14)C]cetrorelix was rapidly and completely absorbed in rats. T(max) in plasma and most tissues was at 2 h. Radioactivity at the injection site in rats declined to 10% by 24 h. The extent of (14)C absorption in rats calculated from excretion until 264 h was 94%. Exposure of the target organ pituitary gland was demonstrated with a time course similar to plasma but on a higher level. Rats excreted 69.6% of radioactivity via feces and 24. 3% into urine. Excretion was nearly complete within 48 h. No enteral reabsorption was detected. In dogs t(max) in plasma was 1.3 h. (14)C- and cetrorelix-plasma levels were similar until 24 h, indicating a negligible amount of metabolites. A dose of 1 mg/kg in dogs showed an increasing influence of a slow absorption phase (flip-flop). In dogs equal amounts of the (14)C dose were found within 192 h in feces and urine, 46 and 48%, respectively. In urine of both species, only intact cetrorelix was detected. In bile and feces of both species qualitatively the same metabolites were found, characterized as truncated peptides of the parent decapeptide. The major metabolite occurring in bile of both species was the (1-7)heptapeptide. The amounts of the (1-4)tetrapeptide in feces of rats but not in that of dogs increase with time, suggesting additional degradation of the peptide in the gastrointestinal tract of rats by enteric metabolization.
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Network formation of lipid membranes: triggering structural transitions by chain melting. Proc Natl Acad Sci U S A 1999; 96:14312-7. [PMID: 10588702 PMCID: PMC24433 DOI: 10.1073/pnas.96.25.14312] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Phospholipids when dispersed in excess water generally form vesicular membrane structures. Cryo-transmission and freeze-fracture electron microscopy are combined here with calorimetry and viscometry to demonstrate the reversible conversion of phosphatidylglycerol aqueous vesicle suspensions to a three-dimensional structure that consists of extended bilayer networks. Thermodynamic analysis indicates that the structural transitions arise from two effects: (i) the enhanced membrane elasticity accompanying the lipid state fluctuations on chain melting and (ii) solvent-associated interactions (including electrostatics) that favor a change in membrane curvature. The material properties of the hydrogels and their reversible formation offer the possibility of future applications, for example in drug delivery, the design of structural switches, or for understanding vesicle fusion or fission processes.
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Metal compounds as tools for the construction and the interpretation of medium-resolution maps of ribosomal particles. J Struct Biol 1999; 127:141-51. [PMID: 10527903 DOI: 10.1006/jsbi.1999.4135] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Procedures were developed exploiting organometallic clusters and coordination compounds in combination with heavy metal salts for derivatization of ribosomal crystals. These enabled the construction of multiple isomorphous replacement (MIR) and multiple isomorphous replacement combined with anomalous scattering medium-resolution electron density maps for the ribosomal particles that yield the crystals diffracting to the highest resolution, 3 A, of the large subunit from Haloarcula marismortui and the small subunit from Thermus thermophilus. The first steps in the interpretation of the 7. 3-A MIR map of the small subunit were made with the aid of a tetrairidium cluster that was covalently attached to exposed sulfhydryls on the particle's surface prior to crystallization. The positions of these sulfhydryls were localized in difference Fourier maps that were constructed with the MIR phases.
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Reconstruction of the acto-myosin interface: new approaches and new results. Biol Cell 1999. [DOI: 10.1016/s0248-4900(99)90100-4] [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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Abstract
We have prepared an undecagold-tagged phalloidin derivative to determine this mushroom toxin's binding site and orientation within the F-actin filament by scanning transmission electron microscopy (STEM) and 3-D helical reconstruction. Remarkably, when stoichiometrically bound to F-actin, the undecagold moiety of the derivative could be directly visualized by STEM along the two half-staggered long-pitch helical strands of single filaments. Most importantly, the structural data obtained when combined with various biochemical constraints enabled us to critically evaluate two distinct atomic models of the F-actin filament (i.e. the Holmes-Lorenz versus the Schutt-Lindberg model). Taken together, our data are in excellent agreement with the Holmes-Lorenz model.
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Polyamine spider toxins and mammalian N-methyl-D-aspartate receptors. Structural basis for channel blocking and binding of argiotoxin636. EUROPEAN JOURNAL OF BIOCHEMISTRY 1996; 240:416-26. [PMID: 8841407 DOI: 10.1111/j.1432-1033.1996.0416h.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Recombinant N-methyl-D-aspartate receptors composed of NR1/NR2A subunits were expressed in Xenopus oocytes to analyse the voltage-dependent and use-dependent channel blocking activity of argiotoxin636. Functional assays demonstrate that the toxin competes with other open channel blockers such as Mg2+ and MK-801. Direct binding or competition assays using radiolabeled ligands and isolated rat brain membranes, in contrast, reveal no specific binding or yield binding constants which differ by orders of magnitude from the IC50 values of the functional assays. One explanation is that argiotoxin636 does not bind with high affinity to the inhibitory site in the N-methyl-D-aspartate-receptor channel under in vitro conditions when membranes are depolarised. The structure of argiotoxin636 was investigated by NMR spectroscopy. In solution the positively charged argiotoxin636 acquires an extended conformation and its dimensions might allow permeation deep into the channel. In the absence of direct structural information on the channel protein, the detailed analysis of blockade in conjunction with structural information, as provided here, may be of aid in the deduction of structural features of glutamate-receptor channel ion pores.
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Anisotropy in the irreversible behavior of pointlike defects and twins in YBa2Cu3O7- delta single crystals with a peak effect. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:644-655. [PMID: 9984300 DOI: 10.1103/physrevb.54.644] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Purification and characterization of subtilisin cleaved actin lacking the segment of residues 43-47 in the DNase I binding loop. Biochemistry 1995; 34:14834-42. [PMID: 7578093 DOI: 10.1021/bi00045a026] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The protease subtilisin has been reported to cleave skeletal muscle G-actin between Met 47 and Gly 48 generating a core fragment of 33 kDa and a small N-terminal peptide, which remains attached to the core fragment [Schwyter, D. Phillips, M., & Reisler, E. (1989) Biochemistry 28, 5889-5895]. However, amino acid sequencing and mass spectroscopy of subtilisin cleaved-actin revealed two cleavage sites, one between Met 47 and Gly 48 and a second between Gly 42 and Val 43, generating an actin core of 37 kDa and a nicked 4.4 kDa N-terminal peptide. Here we describe a procedure for purifying the actin core fragment and the attached N-terminal peptide from the linking pentapeptide comprising amino acid residues 43-47 under native conditions by anion exchange chromatography. After removal of the pentapeptide, the salt-induced polymerization of actin was abolished. However, the purified fragments could be polymerized by addition of salt plus myosin subfragment 1 or salt plus phalloidin as shown by sedimentation and fluorescence increase using N-(1-pyrenyl)iodoacetamide labeled actin. These results confirm earlier reports proposing that cleavage in the DNase I binding loop is affecting the ion induced polymerization of actin [Higashi-Fujime, S., et al. (1992) J. Biochem. (Tokyo) 112, 568-572; and Khaitlina, S., et al. (1993) Eur. J. Biochem. 218, 911-920]. Monomeric and filamentous subactin exhibited reduced abilities to inhibit deoxyribonuclease I (DNase I) and to stimulate the myosin subfragment 1 ATPase activity. Direct binding of subactin to DNase I was verified by gel filtration and to myosin subfragment 1 by affinity chromatography, chemical cross-linking, and electron microscopy.
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Comparison of pinning parameters between low-Tc superconductors and YBa2Cu3O7- delta. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 52:7689-7700. [PMID: 9979714 DOI: 10.1103/physrevb.52.7689] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Histopathology of chemically induced testicular atrophy in rats. EXPERIMENTAL AND TOXICOLOGIC PATHOLOGY : OFFICIAL JOURNAL OF THE GESELLSCHAFT FUR TOXIKOLOGISCHE PATHOLOGIE 1995; 47:267-86. [PMID: 8855122 DOI: 10.1016/s0940-2993(11)80260-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Phase diagram of flux creep in melt-textured and single-crystalline YBa2Cu3O7- delta. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 50:7016-7025. [PMID: 9974658 DOI: 10.1103/physrevb.50.7016] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Comparative study of the peak effect in YBa2Cu3O7- delta single crystals by transport and magnetic measurements. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:15420-15423. [PMID: 10010670 DOI: 10.1103/physrevb.49.15420] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Abstract
Elucidation of the molecular contacts between actin and myosin is central to understanding the force-generating process in muscle and other cells. Actin, a highly conserved globular protein found in all eukaryotes, polymerizes into filaments (F-actin) for most of its biological functions. Myosins, which are more diverse in sequence, share a conserved globular head of about 900 amino acids in length (subfragment-1 or S1) at the N-terminal end of the molecule. S1 contains all the elements necessary for mechano-chemical force transduction in vitro. Here we report an atomic model for the actomyosin complex produced by combining the atomic X-ray structure of F-actin and chicken myosin S1 with a three-dimensional reconstruction from electron micrographs of frozen-hydrated F-actin decorated with recombinant Dictyostelium myosin S1. The accuracy of the reconstruction shows the position of actin and myosin molecules unambiguously.
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Abstract
Cloned NMDA receptor channels of the NR1-NR2A, NR1-NR2B and NR1-NR2C type show differences in argiotoxin636 block. Mutations of an asparagine residue located at a homologous position in the TM2 region of all NMDA receptor subunits, which corresponds to the Q/R site of the AMPA receptors, alters the argiotoxin636-induced block. The results suggest that the toxin interacts at this amino acid position with the putative pore forming TM2 region of the NMDA receptor subunits. Sequence differences in the TM2 segment of NR2A and NR2C subunits are not responsible for the subtype-specific sensitivity to argiotoxin636 as revealed by site-directed mutagenesis.
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Abstract
Argiotoxin, a component of the spider venom from Argiope lobata, blocks AMPA receptor channels expressed in homomeric and heteromeric configuration in Xenopus oocytes. Argiotoxin acts as an open channel blocker in a voltage-dependent manner and discriminates between the functionally diverse AMPA receptors. Importantly, a transmembrane region 2 determinant for divalent cation permeability also determines argiotoxin sensitivity. Subunit-specific differences in the time courses of block and recovery demonstrate that heteromeric AMPA receptors can assemble in variable ratios. Thus, argiotoxin can be used as a tool in analyzing the subunit composition of AMPA receptors in native membranes.
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Compartment syndrome and shin splints of the lower leg. J Manipulative Physiol Ther 1993; 16:245-52. [PMID: 8340719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVES The objective of this article is to review and categorize the current knowledge on compartment syndromes (CS) and shin splints (SS), with specific importance relegated to the diagnosis, differential diagnosis and management of these conditions. DATA SOURCES The bibliographic data sources reviewed are limited to the English language and human content and are from medical and scientific journals, as well as chiropractic and medical texts. A mini-Medline version of Index Medicus was utilized. Terms for indexing included compartment syndromes, shin splints and stress fractures. The bibliographies of the journals selected were then evaluated and, where appropriate, the specific journal or text references regarding diagnosis and management were then reviewed. This information was then included in this article, where useful, to further clarify or reference statements made. CONCLUSION Differential diagnosis of the acute CS from chronic CS and SS requires clinical methods and imaging procedures. The pathogenesis of the acute CS of the lower leg is associated with external pressure or internal hemorrhage. If the tissue pressure were to rise above 30-40 mm Hg for 4-12 h, irreversible muscular damage would result. Emergency surgical intervention is the only appropriate form of treatment in acute CS. In chronic CS, where elevated pressures exist on a transient basis, influenced by activity, conservative management procedures are felt to be effective. However, if these methods are not helpful, surgical intervention may be necessary. The etiology of pain associated with SS is not associated with compartmental pressure elevations, but rather, results from periostitis occurring along the tibia caused by muscular and tendinous strain associated with inflammation. Conservative management is most appropriate for this disorder, with surgical intervention being an uncommon treatment approach. Although clinical findings are useful in the diagnosis of these disorders, fluid pressure findings may be necessary to fully differentiate acute CS from other disorders. Up until recently, common methods of obtaining pressure measurements of compartments included the use of a needle manometer. More recently, however, a hand-held miniature fluid pressure monitor has been developed that produces reproducible measurements of interstitial fluid, making testing potentially practical for the clinician.
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Visualization of a ternary complex of the Escherichia coli Phe-tRNA(Phe) and Tu.GTP from Thermus thermophilus by scanning transmission electron microscopy. J Struct Biol 1993; 110:84-9. [PMID: 8494675 DOI: 10.1006/jsbi.1993.1007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Scanning transmission electron microscopy (STEM) was used to visualize formation of a ternary complex between the T. thermophilus elongation factor (EF) Tu.GTP and the Escherichia coli Phe-tRNA(Phe) labeled with an undecagold (Au11) cluster at minor nucleotide 3-(3-amino-3-carboxypropyl) uridine at position 47. The ternary complex was further characterized by the molecular mass and radius of gyration calculated from the mass distribution within the individual particles. Under conditions used for STEM imaging, the ternary complex is formed between Au11-labeled Phe-tRNA(Phe) and Tu.GTP in a yield up to 25%. The stoichiometry of EF-Tu.GTP to aminoacyl-tRNA (aa-tRNA) in the EF-Tu.GTP.aa-tRNA complex is 1:1, in agreement with the established view of the protein biosynthesis mechanism. The ternary complex is also formed, although to a lower extent, with GTP analogues (GMPPCP and GMPPNP, respectively), but not with Tu.GDP and nonaminoacylated tRNA(Phe) with Tu.GTP.
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Abstract
Argiotoxin636, a component of the spider venom of argiope species, was chemically synthesized together with a number of derivatives in order to analyse their blocking activity on mammalian glutamate receptors. Xenopus laevis oocytes injected with rat brain mRNA served as assay system. The results showed that argiotoxin636 had a higher affinity for N-methyl-D-aspartate (NMDA) than for kainate receptors, blocking the corresponding ion channels in a voltage-dependent manner. Modifications of the polyamine tail or the terminal arginine residue strongly reduced the blocking potency. The iodinated monohydroxyl phenylderivatives, however, retained their NMDA-selective binding and could serve as non-competitive antagonists for radioligand binding assays aiding in the biochemical isolation of glutamate receptors.
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Criterion and selection of optimal subsets in the linear regression,two stage procedures. COMMUN STAT-THEOR M 1991. [DOI: 10.1080/03610929108830588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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[The development of cases of medical damage in West Germany]. DER GYNAKOLOGE 1989; 22:411-5. [PMID: 2625275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Novel procedures for derivatization of ribosomes for crystallographic studies. J Biol Chem 1989; 264:19138-42. [PMID: 2808418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Undecagold and tetrairidium clusters have been used for the preparation of heavy-metal derivatives of ribosomal particles, necessary for the evaluation of phases in the x-ray structure determination of these large particles. To obtain specific binding, monofunctional reagents of the clusters were prepared and were covalently bound to free sulfhydryl groups on the surface of the ribosome. In addition, a mutant of Bacillus stearothermophilus which lacks one ribosomal protein (BL11) was grown. The heavy-atom clusters were covalently bound to isolated protein BL11, and the modified protein was consequently reconstituted into the mutated ribosomal subunits. Crystallographic data have been collected from crystals of native particles, from the mutated ones, and from the iridium- and gold-derivatized subunits. All these crystal forms are isomorphous within the experimental error.
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A new model for inflammatory colonic disease induced by capsaicin in rats. AGENTS AND ACTIONS 1989; 26:222-3. [PMID: 2711937 DOI: 10.1007/bf02126617] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Book review. STATISTICS-ABINGDON 1989. [DOI: 10.1080/02331888908802158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Present results and further developments on safety analysis of small and medium-sized HTRs for core heat-up accidents. NUCLEAR ENGINEERING AND DESIGN 1988. [DOI: 10.1016/0029-5493(88)90171-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Methods of preparing well-orientated sols of f-actin containing filaments suitable for X-ray diffraction. J Mol Biol 1987; 197:679-84. [PMID: 3430597 DOI: 10.1016/0022-2836(87)90474-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In this paper we describe methods of preparing orientated f-actin and reconstituting thin filaments that are suitable for X-ray diffraction that allow us to analyse the structure of f-actin to at least 15 A resolution (1 A = 0.1 nm). We described problems that occur during the process of orientation and ways of solving them.
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Antamanide antagonizes the phalloidin-induced negative inotropic effect and blocks voltage dependently the fast outward K+ current in voltage-clamped frog muscle fibres. Eur J Pharmacol 1987; 138:21-7. [PMID: 2442001 DOI: 10.1016/0014-2999(87)90332-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The effects of antamanide (10(-14)-10(-5) M) and N-acetyl-secophalloidin (10(-7)-5 X 10(-3) M) a neutral non-toxic derivative of phalloidin, were tested on voltage-clamped single frog muscle fibres. Antamanide protected muscle fibres against the negative inotropic effect of phalloidin but blocked the fast potassium permeability in the same concentration range and the same voltage-dependent manner as did phalloidin. N-Acetyl-secophalloidin exhibited a strongly attenuated blocking effect on K+ permeability in a 1,000-fold higher concentration range than phalloidin. Neither antamanide nor N-acetyl-secophalloidin affected the contractile properties. These results suggest the existence in the frog muscle membrane of a receptor with two sites for phalloidin and antamanide which acts on potassium conductance.
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Book Review. STATISTICS-ABINGDON 1987. [DOI: 10.1080/02331888708802035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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[Biostatistical models in experimental gerontology]. ZEITSCHRIFT FUR DIE GESAMTE INNERE MEDIZIN UND IHRE GRENZGEBIETE 1986; 41:134-6. [PMID: 3716504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Morphometric measuring values present themselves in a definite distribution which changes in the ageing process. This change of distribution can be clarified by distribution analyses. Another task within the analysis of frequency distributions is the decomposition of mixed distributions, as they may appear in various parameters in the course of life. The linear regression analysis is, for instance, to be used in the verification of sexual divergencies in the process of ageing. An adaptation of non-linear exponential functions to series of measuring values serves, among others, to make evidence concerning the ageing rapidity of the tissues. When in gerontological inquiries at the same time many different characteristics are determined also the degree of their ageing dependency is of interest. This is to be established by means of a special transformation within the factor analysis. Finally the study shows instances for the application of contingency tables in qualitative characteristics and the investigation of their frequency in the process of ageing as well as for the use of the cluster analysis.
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Alpha-1-antitrypsin: evidence for a fifth PI M subtype and a new deficiency allele PI*Z augsburg. Hum Genet 1985; 71:27-9. [PMID: 3875547 DOI: 10.1007/bf00295662] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The phenotypes of the protease inhibitor (PI) alpha-1-antitrypsin have been analyzed by isoelectric focusing on polyacrylamide gels. With improved resolution by a modified procedure it was possible to demonstrate a fifth PI*M suballele. The bands of PI M5 are located between PI M1 and PI M3. In addition, a further deficiency allele similar to PI*Z was found in a female patient with obstructive pulmonary disease. This variant was provisionally named PI Z augsburg (PI Z aug). Family data confirm a simple codominant mode of inheritance for PI Z aug.
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Zur Elektronenstruktur metallorganischer Komplexe der ⨍-Elemente—X. Zuordnung der Banden im Absorptionsspektrum von Tris(η5-cyclopentadienyl)-praseodym(III)-cyclohexylisonitril. ACTA ACUST UNITED AC 1985. [DOI: 10.1016/0584-8539(85)80152-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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