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2.  Severe heparin osteoporosis in pregnancy. 
Postgraduate Medical Journal  1984;60(704):424-425.
A case of severe osteoporosis following administration of low dose subcutaneous heparin in pregnancy is reported. Possible reasons for the condition are suggested which caution against the indiscriminate use of subcutaneous heparin in pregnancy.
PMCID: PMC2417911  PMID: 6462984
3.  Radioimmunofocus assay for detection and quantitation of human rotavirus. 
Journal of Clinical Microbiology  1984;20(3):347-350.
A radioimmunofocus assay suitable for quantitation of cell culture-adapted human rotavirus was developed. The method was reproducible, more sensitive than plaque assay, and useful to detect and quantify strains of rotavirus which do not produce plaques. Preliminary results also suggested that the technique will be a useful means of serotyping cell culture-adapted strains of the virus.
PMCID: PMC271327  PMID: 6092422
4.  Formate dehydrogenase of Clostridium pasteurianum. 
Journal of Bacteriology  1984;159(1):375-380.
Formate dehydrogenase was purified to electrophoretic homogeneity from N2-fixing cells of Clostridium pasteurianum W5. The purified enzyme has a minimal Mr of 117,000 with two nonidentical subunits with molecular weights of 76,000 and 34,000, respectively. It contains 2 mol of molybdenum, 24 mol of nonheme iron, and 28 mol of acid-labile sulfide per mol of enzyme; no other metal ions were detected. Analysis of its iron-sulfur centers by ligand exchange techniques showed that 20 iron atoms of formate dehydrogenase can be extruded as Fe4S4 centers. Fluorescence analysis of its isolated molybdenum centers suggests it is a molybdopterin. The clostridial formate dehydrogenase has a pH optimum between 8.3 and 8.5 and a temperature optimum of 52 degrees C. The Km for formate is 1.72 mM with a Vmax of 551 mumol of methyl viologen reduced per min per mg of protein. Sodium azide competes competitively with formate (K1 = 3.57 microM), whereas the inactivation by cyanide follows pseudo-first-order kinetics with K = 5 X 10(2) M-1 s-1.
PMCID: PMC215640  PMID: 6547435
5.  Identification of Nitroso Compounds from Biotransformation of 2,4-Dinitrotoluene 
The intermediates of microbial transformation of 2,4-dinitrotoluene by a mixed bacterial culture derived from activated sludge were identified as 2-amino-4-nitrotoluene, 4-amino-2-nitrotoluene, 2-nitroso-4-nitrotoluene, and 4-nitroso-2-nitrotoluene. The biotransformation of 2,4-dinitrotoluene occurred only under anaerobic conditions with an exogenous carbon source. The two nitroso compounds were unstable and could be observed only at the early stage of 2,4-dinitrotoluene anaerobic biotransformation.
PMCID: PMC240225  PMID: 16346568
6.  A molecular defect of spectrin in a subset of patients with hereditary elliptocytosis. Alterations in the alpha-subunit domain involved in spectrin self-association. 
Journal of Clinical Investigation  1984;73(6):1688-1695.
Hereditary elliptocytosis (HE) is a clinically and biochemically heterogenous group of diseases characterized by elliptically shaped erythrocytes and an autosomal dominant mode of inheritance. Whereas the self-association of spectrin heterodimers to tetramers is defective in a subpopulation of HE patients, designated HE[SpD-SpD], it is normal in others. We have examined the peptide pattern produced by limited tryptic digestion of spectrin extracts from patients with HE[SpD-SpD] to determine if the functional defects in spectrin self-association could be correlated with structural changes in the spectrin molecule. Although the peptide pattern produced by limited tryptic digestion of spectrin extracts from those HE patients with normal spectrin self-association was indistinguishable from the pattern from control normal volunteers, digestion of the spectrin extracts from the HE[SpD-SpD] patients showed a reproducible diminution in the 80,000-D domain of the alpha-subunit, which is involved in spectrin dimer self-association. The decrease in the 80,000-D fragment was associated with an increase in a 74,000-D fragment in eight of nine families, or, in one family, with an increase of fragments at 46,000 and 17,000 D. These atypical peptide patterns were similar to those previously reported in two variants of hereditary pyropoikilocytosis (HPP), which also had defective self-association of spectrin. These data indicate that two distinct structural variants of spectrin alpha-subunit are associated with the defective spectrin heterodimer self-association in a subpopulation of HE patients.
PMCID: PMC437080  PMID: 6725555
7.  Comparative Cytochrome Oxidase and Superoxide Dismutase Analyses on Strains of Azotobacter vinelandii and Other Related Free-Living Nitrogen-Fixing Bacteria 
Quantitative N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) oxidase and superoxide dismutase (SOD) analyses were performed on representative organisms of the family Azotobacteraceae. Azotobacter vinelandii, Azotobacter chroococcum, Azotobacter paspali, and Derxia gummosa exhibited high quantitative TMPD oxidase activities, and their extracts possessed very active and electrophoretically homogeneous (single gel band) Fe-type SODs. Azomonas macrocytogenes extracts had similar single Fe-type SODs, and their cells exhibited no TMPD-dependent cytochrome oxidase activity. Nitrogen-fixing cells of Beijerinckia indica, Beijerinckia derxii, and Beijerinckia mobilis exhibited minimal TMPD oxidation capabilities (rates equivalent to the TMPD autooxidation reaction), and these extracts also possessed very active SODs but only of the Mn metallotype.
PMCID: PMC240103  PMID: 16346548
8.  Mycobacterium thermoresistibile infection in an immunocompromised host. 
Journal of Clinical Microbiology  1984;19(4):546-547.
This is the second report of Mycobacterium thermoresistibile as the etiological agent of a pulmonary granuloma and the first occurrence of this organism in a patient who has not been outside the continental United States. The organism is susceptible to rifampin, ethambutol, and streptomycin but resistant to isoniazid and p-aminosalicylic acid.
PMCID: PMC271115  PMID: 6715522
9.  Seventh-Day Adventist Adolescents—Life-style Patterns and Cardiovascular Risk Factors 
Western Journal of Medicine  1984;140(3):471-477.
The life-style of adolescents attending a Seventh-Day Adventist boarding school was evaluated as it related to cardiovascular risk factors. The diet contained 34% calories as fat, with 11% derived from saturated fat. Total serum cholesterol levels were low (mean, standard deviation=138±15 mg per dl), and apolipoprotein B level was low as well (46±9 mg per dl). The high-density lipoprotein cholesterol level was within the usual range (52.4±13.3 mg per dl). Mean blood pressures were also low (systolic, 104.1±9.6 mm of mercury; diastolic, 65.7±9.7 mm of mercury). There was no self-reported use of cigarettes. If this life-style were to continue through adulthood, the incidence of premature atherosclerotic disease, particularly coronary artery disease, for this group might well be reduced, compared with other North Americans, as suggested by findings from previous studies of adult Seventh-Day Adventists.
PMCID: PMC1021728  PMID: 6710991
10.  Effect of inspiratory flow rate on bronchomotor tone in normal and asthmatic subjects. 
Thorax  1984;39(2):86-92.
The effect of the inspiratory flow rate during deep inspiration on the regulation of bronchomotor tone was studied in nine normal and 22 asthmatic subjects. Changes in bronchial tone were assessed by respiratory resistance measured by an oscillation method. In normal subjects with bronchoconstriction induced by methacholine a rapid deep inspiration reduced respiratory resistance more than a slow deep inspiration. Asthmatic subjects with spontaneous airway narrowing showed an increase in respiratory resistance after deep inspiration that was greater after rapid than after slow deep inspiration. On the other hand, in asthmatics with methacholine induced bronchoconstriction, bronchodilatation occurred after deep inspiration and this was also greater after rapid than after slow deep inspiration. Lignocaine inhalation attenuated both bronchoconstriction and bronchodilatation induced by both slow and rapid deep inspiration. These results suggest that the effects of deep inspiration are mediated at least in part via receptors in the airways. It is suggested that in asthmatic patients with spontaneous bronchoconstriction irritant receptor activity will be increased in proportion to the speed of inspiration. After methacholine induced bronchoconstriction stretch receptor activity is likely to behave in a similar fashion, leading to an opposite effect.
PMCID: PMC459732  PMID: 6367130
11.  Modulation of cell-associated plasminogen activator activity by cocultivation of a stem cell and its tumorigenic descendant. 
Molecular and Cellular Biology  1984;4(1):160-165.
The effect of the presence of one cell type on the plasminogen activator activity of another cell type was studied. The cell types, AC and D, were isolated from a rat neuroblastoma (I. Imada and N. Sueoka, Dev. Biol. 66:97-108, 1978). AC cells are stem cells capable of multipotential differentiation in vitro and have little or no cell-associated plasminogen activator activity. D cells are tumorigenic and have high levels of cell-associated plasminogen activator activity. When AC cells were cocultivated with D cells, the plasminogen activator activity of the D cells was dramatically inhibited. The presence of as few as 1,250 AC cells inhibited 70% of the plasminogen activator activity of 20,000 D cells, as determined by a highly quantitative assay. The amount of inhibition by AC cells was proportional to the number of AC cells present. At increasing numbers of AC cells and a constant number of D cells, the Vmax for the activation of plasminogen proportionately decreased and the Km remained constant, implying that AC cells did not alter the structure or concentration of plasminogen. Inhibition was not mediated by a soluble inhibitor secreted by AC cells. Rather, attachment of AC cells adjacent to D cells, i.e., cell-to-cell contact, seemed to be required for inhibition. The substratum-attached material of AC cells, that which remained on the microwell surface after removal of AC cells with EDTA, inhibited D cell plasminogen activator activity. If plasminogen activator activity is involved in metastasis, then regulation of the plasminogen activator activity of one cell type by another cell type may be involved in determining which cells in a tumor can metastasize and where secondary tumors can arise.
PMCID: PMC368670  PMID: 6538259
12.  Primary and secondary structure of dinoflagellate U5 small nuclear RNA. 
Nucleic Acids Research  1984;12(3):1529-1542.
U5 RNA is one of the six capped small nuclear RNAs present in most eukaryotic cells. Like U1, U2, U4 and U6 RNAs, U5 RNA is associated with hnRNP particles and is thus probably involved in some, as yet undefined, aspects of pre-messenger RNA processing. In this study, the complete nucleotide sequence of U5 RNA of a dinoflagellate, Crypthecodinium cohnii was determined. The analysis of this dinoflagellate U5 RNA sequence showed that a) the sequence homology between human, rat and chicken U5 RNA sequences and dinoflagellate U5 RNA sequence is 64%; b) the extent and the position of post-transcriptional modifications are similar to those found in U5 RNA of higher eukaryotes; c) although the dinoflagellate U5 RNA is shorter in length (108 nucleotides long vs 117 long in human, rat and chicken cells), the RNA fits well into the same secondary structure proposed for U5 RNA of higher eukaryotes (Krol et al. (1981) Nucl. Acids Res. 9, 769); and d) the AUn nucleotide sequence protected by the Sm-antigen and the tight secondary structure found near the 3'-end of other U-RNAs was also found in dinoflagellate U5 RNA. The high order of homology observed between dinoflagellate U5 RNA and U5 RNA of higher eukaryotes indicates that dinoflagellates are more closely related to metazoans than to early eukaryotes.
PMCID: PMC318594  PMID: 6199742

Results 1-12 (12)