3051
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[Long-term domiciliary oxygen therapy of cardiac failure and cardiac arrhythmia accompanying respiratory insufficiency (author's transl)]. PRAXIS UND KLINIK DER PNEUMOLOGIE 1981; 35:532-7. [PMID: 6808483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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3052
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3053
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Inhibition of proteases by alpha 2-macroglobulin. The role of lysyl amino groups of trypsin in covalent complex formation. J Biol Chem 1981; 256:10409-14. [PMID: 6169720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The lysyl amino groups of bovine trypsin were covalently modified by acetylation, succinylation, or reductive methylation. The enzymatically active derivatives were still capable of reaction with alpha 2-macroglobulin (alpha 2M), although to a lesser extent than native enzyme. The resulting enzyme-alpha 2M complexes, however, were much more susceptible to dissociation by sodium dodecyl sulfate than complexes formed with unmodified trypsin. The bound modified enzymes could be released from the alpha 2M complex with an excess of native thrombin. In addition, anhydrotrypsin displaced methyl trypsin from its complex and the anhydro derivative was bound in its place. The data provide evidence for two types of noncovalent intermediates; those formed from lysyl-modified enzymes show proteolysis of the alpha 2M to the nominal 85,000 fragment, whereas anhydrotrypsin forms a complex with apparently intact alpha 2M chains. A model is proposed for the reaction of alpha 2M with proteases in which one or both of these noncovalent intermediates is formed. Conversion of this form(s) to a stable covalent complex requires unmodified lysyl amino groups on the enzyme, suggesting that these groups may form a covalent bond with the inhibitor, possibly at the site at which methylamine binds.
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3054
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Inhibition of proteases by alpha 2-macroglobulin. The role of lysyl amino groups of trypsin in covalent complex formation. J Biol Chem 1981. [DOI: 10.1016/s0021-9258(19)68634-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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3055
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Alpha 2-macroglobulin-protease reactions: relationship of covalent bond formation, methylamine reactivity, and specific proteolysis. Arch Biochem Biophys 1981; 211:500-6. [PMID: 6171201 DOI: 10.1016/0003-9861(81)90483-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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3056
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Acute viral infection of the central nervous system in children: an 8-year review. CANADIAN MEDICAL ASSOCIATION JOURNAL 1981; 125:585-9. [PMID: 7284937 PMCID: PMC1862633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Reliable information on acute viral infections of the central nervous system (CNS) in Canadian children has not been available. To investigation this disease in Halifax the medical records of 180 patients with presumed or definite acute viral CNS infection diagnosed at the Izaak Walton Killam Hospital for Children over an 8-year period were reviewed. The yearly incidence was estimated at 19.5/100 000 for children up to 16 years of age, and the peak incidence was in July, August and September. The cause was determined in 64 (36%) of the 180 patients; it was most commonly a known infectious disease -- mumps (in 24 patients) or varicella (in 9 patients). An enterovirus was responsible in nine cases, herpes simplex virus in eight and measles virus in six. The clinical manifestations were variable and included apnea in three infants who would otherwise have been considered to have nearly suffered the sudden infant death syndrome. Localizing features were present on the electroencephalograms of nine patients, including six with herpes simplex infection. Serologic study of paired serum samples obtained during the acute phase of the illness and during convalescence was the most useful laboratory method of establishing the diagnosis. As medical therapy for specific causes of acute viral CNS infection advances, greater attention should be placed on establishing the correct diagnosis.
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3057
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Studies on immunopathogenesis in epidemic hemorrhagic fever: sequential observations on activation of the first complement component in sera from patients with epidemic hemorrhagic fever. THE JOURNAL OF IMMUNOLOGY 1981. [DOI: 10.4049/jimmunol.127.3.1064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Sequential measurements of activation of the 1st component of complement (C1) in the sera of 29 patients hospitalized with epidemic hemorrhagic fever (EHF) were performed according to a method recently developed. These patients were treated with supportive, routine therapy, but not immunosuppressive agents. This paper describes the kinetic observations on the activation of C1 in the 29 cases. The data confirm that an apparently increased extent of activation occurred in their sera. It was found that the more severely ill the patients were, the more apparent the activation. Additionally, beginning with the 15th day of disease, the extent of C1 activation diminished in most of the moderate and severe types of patients, but not in those with moribund illness and fatal ones. On the basis of the study, it may be reasonably concluded that C1 activation was correlated well with the severity and clinical course of EHF, indicating that the classical C pathway was activated in these patients. We feel that our findings are important to an understanding and elucidation of the immunopathogenetic mechanisms of EHF.
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3058
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Studies on immunopathogenesis in epidemic hemorrhagic fever: sequential observations on activation of the first complement component in sera from patients with epidemic hemorrhagic fever. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1981; 127:1064-7. [PMID: 6114975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Sequential measurements of activation of the 1st component of complement (C1) in the sera of 29 patients hospitalized with epidemic hemorrhagic fever (EHF) were performed according to a method recently developed. These patients were treated with supportive, routine therapy, but not immunosuppressive agents. This paper describes the kinetic observations on the activation of C1 in the 29 cases. The data confirm that an apparently increased extent of activation occurred in their sera. It was found that the more severely ill the patients were, the more apparent the activation. Additionally, beginning with the 15th day of disease, the extent of C1 activation diminished in most of the moderate and severe types of patients, but not in those with moribund illness and fatal ones. On the basis of the study, it may be reasonably concluded that C1 activation was correlated well with the severity and clinical course of EHF, indicating that the classical C pathway was activated in these patients. We feel that our findings are important to an understanding and elucidation of the immunopathogenetic mechanisms of EHF.
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3059
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Complexing reverse transcriptase with polyspermine-ribonuclease. Biochem J 1980; 189:89-93. [PMID: 6161606 PMCID: PMC1161920 DOI: 10.1042/bj1890089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Polyspermine-ribonuclease (Mr approximately 17 000) and the enzyme transcriptase from Rauscher-leukaemia virus (Mr approximately 70 000) form a complex Mr approx. 160 000) such that the molar ratio of polyspermine-ribonuclease to reverse transcriptase is 5:1. The most favourable condition for complex-formation is in a solution consisting of 0.01 M-Tris/HCl buffer, pH 7.5, 0.25 M-KCl and 1 mM-Mn2+ at 37 degrees C. The association of the two enzymes retains full RNAase activity, but reverse-transcriptase activity is completely inhibited when ribonuclease-sensitive polymers such as (dG)12 x (rC)n or viral 70S RNA are used as primer templates.
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3060
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[Synthesis of some (2-hydroxy-3-aminopropoxy) flavones (author's transl)]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1980; 15:253-6. [PMID: 6109426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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3061
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Abstract
Protease-free bovine pancreatic deoxyribonuclease (DNase) (1.6 X 10(-4) mmol) was thiolated on the NH2 groups with N-acetyl-DL-homocysteine thiolactone (2.4 X 10(-2) mmol) at pH 10.5 with imidazole (2.4 X 10(-2) mmol) as the catalyst in the presence of 4,4'-dithiodipyridine (4.2 X 10(-2) mmol). The product obtained after 16 h at 4 degrees C, 2-acetamido-4-(4'-dithiopyridyl)butyryl-DNase, isolated by gel filtration, contained an average of 0.87 +/- 0.13 mol of mixed disulfide per mol of DNase. Ribonuclease (RNase) was thiolated in a similar manner, but under N2 in the absence of 4,4'-dithiodipyridine. The protein N-acetylhomocysteinyl-RNase contained on the average 0.94 +/- 0.11 mol of sulfhydryl groups per mol of RNase. The coupling of RNase ot DNase was accomplished by thiol-disulfide interchange at pH 6.2 and 25 degrees C for 90 min. The hybrid enzyme (yield 25--33%, based upon the DNase derivative used) was freed from unreacted DNase, RNase, and homodimers by gel filtration, affinity chromatography, and salting-out chromatography. The purified enzyme contained one molecule each of DNase and RNase and hydrolyzed thymus deoxyribonucleic acid (DNA) and yeast or transfer ribonucleic acid (RNA) with 75 and 40% of the efficiencies, respectively, of the parent enzymes. The RNA strand of the hybrid substrate, phage f1 DNA-[3H]RNA, prepared from phage DNA with RNA polymerase, was hydrolyzed rapidly by the hybrid enzyme but was not hydrolyzed by RNase alone. A conjugate of the two enzymes offers the possibility in vivo of delivering two enzymes that differ in size, charge, and biological function to the same site at the same time.
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3062
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Observations on the kinetics of action of polyspermine-ribonuclease on poly(A).poly(U). BIOCHIMICA ET BIOPHYSICA ACTA 1979; 568:488-90. [PMID: 486496 DOI: 10.1016/0005-2744(79)90318-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Starting from the observation that double-stranded ribonucleic acids are hydrolyzed more rapidly by bovine pancreatic ribonuclease that has been cross-linked to polyspermine, we have made an initial examination of the kinetics of the process. The addition of eight residues of the polyamine serves to strengthen the binding to poly(A).poly(U) 100-fold (Km changes from 2.7 . 10(-4) to 2.7 . 10(-6) M in total U) and to increase V for hydrolysis of the susceptible poly(U) strand from 2.5 to 16.2 delta A250 . min-1 per mg enzyme. There is evidence for inhibition by the RNAase-resistant poly(A) tracts in the substrate; free poly(A) shows a Ki of about 8 . 10(-6) M in total A.
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3063
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Hydrolysis and dissolution behavior of a prolonged-release prodrug of theophylline: 7,7'-succinylditheophylline. J Pharm Sci 1979; 68:288-95. [PMID: 34020 DOI: 10.1002/jps.2600680309] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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3064
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Preparation of protease-free and ribonuclease-free pancreatic deoxyribonuclease. J Biol Chem 1978; 253:7216-9. [PMID: 701244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
When pancreatic DNase I is used as a specific biochemical reagent in the preparation of nuclear ribonucleic acids or nuclear proteins, freedom from contaminating ribonucleases or proteases is an important property of the enzyme preparation. A simple one-step procedure has been developed to effect complete removal of trypsin, chymotrypsin, and chymotrypsinogen by a combination of affinity chromatography and salting-out adsorption on lima bean protease inhibitor coupled to Sepharose (a column (0.9 X 60 cm) operated in series with a regeneratable 1-ml bed). Commercial preparations of DNase (about 10 mg) give a quantitative yield of the enzyme that is protease-free as evidenced by full stability for more than 10 days at pH 8 and 37 degrees C even in the absence of the protecting action of Ca2+. Removal of the last traces of RNase has been accomplished by affinity chromatography on a column (0.4 X 72 cm) of 5'-(4-aminophenyl-phosphoryl)-uridine 2'(3')-phosphate-Sepharose; the product is a highly active DNase that gives no detectable hydrolysis of RNA by assay on radioactive substrates.
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3065
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The ODA is here to stay: Patient care before labels for staff. NURSING TIMES 1978; 74:1715-6. [PMID: 250768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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3066
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3067
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Abstract
Piperacillin, a new semisynthetic penicillin, was compared with other semisynthetic penicillins, cephalosporins, and aminoglycosides by the agar dilution method against 3,600 isolates of facultative gram-negative bacilli, Bacteroides fragilis, and enterococci. At 64 mug/ml, piperacillin inhibited 90% of the isolates in each group of organisms tested except for Escherichia coli (83% inhibited by 64 mug/ml). Compared with carbenicillin, piperacillin had a 16-fold increase in activity by weight against Pseudomonas aeruginosa and the enterococcus, an 8-fold increase against Serratia marcescens, and a 4-fold increase against B. fragilis and Enterobacter species. Piperacillin was highly active against carbenicillin-resistant Klebsiella pneumoniae and inhibited many aminoglycoside-resistant organisms. Except for P. aeruginosa, the minimum bactericidal concentration of piperacillin was usually within one tube dilution of the minimum inhibitory concentration. Approximately one-third of the gram-negative bacilli were inhibited synergistically by piperacillin plus amikacin, but no synergy could be demonstrated against enterococci. Piperacillin's in vitro activity against gram-negative bacilli was similar to gentamicin's except that it also included B. fragilis, and piperacillin was decidedly superior to presently available penicillins against K. pneumoniae.
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3068
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3069
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Comparison of antitumor activities of pancreatic ribonuclease and its cross-linked dimer. Cancer Res 1976; 36:4074-8. [PMID: 975050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The cross-linked dimer of bovine pancreatic RNase (M.W. 28,000) is significantly more effective than the monomer in inhibiting tumor development in mice when administered i.p. 1 day after inoculation with sarcoma 180J ascites cells. Animals bearing solid tumors were not affected. In AKR/J mice with advanced leukemia, a single i.p. injection of 100 mug of the dimer led to about 50% reduction in the enlarged lymph nodes and the spleen at 24 hr. The half-life of the dimer in the bloodstream has been determined to be 10 min in rats and 6 min in mice, compared to values of 5 and 3.5 min, respectively, for the monomer. Analyses of the tissues of untreated leukemic mice for RNase and RNase inhibitors show that the tumor tissues are not deficient in RNase activity. Considerations of possible mechanisms of action of the dimer indicate that other basic proteins in this size range may merit examination as cytostatic agents toward transformed cells.
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3070
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Abstract
The cross-linking reaction between diimido esters and ribonuclease has been studied in terms of the yield of cross-linked dimer with optimum activity toward double-stranded RNA. With dimethyl suberimidate the most satisfactory conditions were condensation for 15 min at pH 7.5-8.0 at 21 degrees C with 1.25 mol equiv of the diimido ester and a protein concentration of 6%. The dimer (yield 20%) had 19 unmodified NH2 groups out of a theoretical 20 for a molecule in which two such groups are involved in the cross-linkage; the activity toward poly(A)-poly(U) in 0.14 M salt solution by spectrophotometric assay was 8.5 times that of the monomeric enzyme toward the same substrate.
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3071
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[Synthesis of n-substituted beta-methyl DL-aspartates as potential hypocholesteremics (author's transl)]. Arch Pharm (Weinheim) 1975; 308:564-70. [PMID: 1164178 DOI: 10.1002/ardp.19753080712] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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3072
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A crystalline protein-proteinase inhibitor from pinto bean seeds. BIOCHIMICA ET BIOPHYSICA ACTA 1975; 393:583-96. [PMID: 1148227 DOI: 10.1016/0005-2795(75)90085-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A crystalline protein-proteinase inhibitor has been isolated from seeds of Pinto bean (Phaseolus vulgaris cultvar. Pinto). It has an average molecular weight of 19 000 as estimated by gel filtration. This crystalline inhibitor is highly active against both bovine pancreatic trypsin and alpha-chymotrypsin. Complexes of both trypsin-inhibitor and alpha-chymotrypsin-inhibitor have been isolated. The inhibitor which was derived from the dissociated trypsin-inhibitor complex was only 62% as effective as the original compound against either enzyme. In contrast, the inhibitor obtained from alpha-chymotrypsin-inhibitor complex retained its full original inhibitory activity for trypsin, but only 25% of its original activity against alpha-chymotrypsin. The dissociated inhibitor from alpha-chymotrypsin-inhibitor compex, despite its full inhibitory activity, had been modified to such an extent that it could no longer form any precipitable complex with trypsin. The crystalline protein-proteinase inhibitor is not homogeneous and has been resolved into two distinct inhibitors in terms of their physical and chemical properties. These two inhibitors are designated as Pinto bean proteinase inhibitor I and II and their respective minimum molecular weights are 9100 and 10 000. They differ most strikingly in their amino acid composition in that inhibitor II is void of both valine and methionine.
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3073
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Relationship of soil constituents to spore counts and heat resistance of Bacillus stearothermophilus. Can J Microbiol 1974; 20:1625-31. [PMID: 4441977 DOI: 10.1139/m74-253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Spore counts and heat resistance of Bacillus stearothermophilus and thermophilic actinomycetes were influenced by types of crops and were correlated positively with Mn, Ca, P, pHw, and pHs of soil from Sanborn Field, Columbia, Mo. In greenhouse soil, positive correlations were found between thermophilic aerobes and Mg, Ca, K, and cation-exchange capacity. Also, in the greenhouse soil, negative correlations occurred between counts for thermophilic aerobes and pHw and pHs. Spores in soils in Sanborn Field were more heat- resistant than spores in greenhouse soil. The number of germinating spores in dry soil stored at 25Cand 1.1C increased after 1 month and remained at the same relative number for 9 months at which time counts declined at both temperatures.
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3074
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Kinetics and Thermodynamics of the Interaction of Proteinases with Protein Inhibitors. BAYER-SYMPOSIUM 1974. [DOI: 10.1007/978-3-642-87966-1_45] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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3075
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Biosynthesis of nucleotides in wheat. IV. Metabolism of specifically 14-C-labeled orotic acid. CANADIAN JOURNAL OF BIOCHEMISTRY 1967; 45:721-8. [PMID: 6035138 DOI: 10.1139/o67-082] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The biosynthesis of pyrimidine nucleotides in wheat leaves was investigated, with specifically14C-labeled orotic acids as precursors. The utilization of orotic acid, unlike uracil, for the synthesis of pyrimidine nucleotides is far more predominant than the degradative process. The labeled orotic acid was rapidly metabolized to uracil nucleotides and the sugar nucleotide, uridine-5′-diphosphate glucose. However, cytosine nucleotides were not significantly labeled within 60 minutes. In spite of the fact that no detectable radioactive OMP was observed, the results presented indicate strongly that the biosynthetic pathway for pyrimidine nucleotides from orotic acid in this plant proceeds according to the following reactions: orotic acid + 5-phosphoribosyl-1-pyrophosphate → orotidine-5′-monophosphate → uridine-5′-monophosphate → uridine-5′-triphosphate → uridine-5′-diphosphate glucose, and uridine-5′-triphosphate → cytidine-5′-triphosphate.
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3076
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Carbon Metabolism of C-Labeled Amino Acids in Wheat Leaves. II. Serine & its Role in Glycine Metabolism. PLANT PHYSIOLOGY 1963; 38:430-9. [PMID: 16655811 PMCID: PMC549948 DOI: 10.1104/pp.38.4.430] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
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3077
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Carbon metabolism of C-labeled amino acids in wheat leaves. I. A pathway of glyoxylate-serine metabolism. PLANT PHYSIOLOGY 1962; 37:826-32. [PMID: 16655737 PMCID: PMC406255 DOI: 10.1104/pp.37.6.826] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
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