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L Norlander

Publications and source records attributed to L Norlander.

31 records · Page 2Linked to original sources
PubMed1982

Studies by electron-paramagnetic-resonance spectroscopy of the molybdenum centre of aldehyde oxidase.

Molybdenum(V) e.p.r. spectra from reduced forms of aldehyde oxidase were obtained and compared with those from xanthine oxidase. Inhibited and Desulpho Inhibited signals from aldehyde oxidase were fully characterized, and parameters were obtained with the help of computer simulations. These differ slightly but significantly from the corresponding parameters for the xanthine oxidase signals. Rapid type 1 and type 2 and Slow signals were obtained from aldehyde oxidase, but were not fully characterized. From the general similarities of the signals from the two enzymes, it is concluded that the ligands of molybdenum must be identical and that the overall co-ordination geometries must be closely similar in the enzymes. The striking differences in substrate specificity must relate primarily to structural differences in a part of the active centre concerned with substrate binding and not involving the catalytically important molybdenum site.

Aldehyde Oxidase↗
PubMed1982

Temperature-inducible outer membrane protein of Yersinia pseudotuberculosis and Yersinia enterocolitica is associated with the virulence plasmid.

A strain of Yersinia pseudotuberculosis which harbors a 63-kilobase plasmid was found to cause a lethal infection in Swiss albino mice. The rate of infection paralleled the ability of the pathogenic organism to attach to a monolayer of HeLa cells. One novel outer membrane protein (protein 1) with a molecular weight of 140,000 was found to be associated with the possession of the 63-kilobase plasmid not at 26 degrees C, and expression was moderately affected by the concentration of calcium in the growth medium. Moreover, it was found that synthesis of protein 1 associated outer membrane protein showing similar properties was also found to be expressed in plasmid-containing strains of Yersinia enterocolitica. The properties of protein 1 indicate that it could be identical to the previously described virulence W antigen.

Adhesiveness↗
PubMed1981

Deoxyribonucleic acid modifications and restriction endonuclease production in Neisseria gonorrhoeae.

Modification of gonococcal deoxyribonucleic acid (DNA) was investigated, and the relationship with endonuclease production was explored. Both chromosomal and plasmid DNA from different gonococcal strains, irrespective of their plasmid content, was poorly cleaved by the restriction endonucleases HaeII, HaeIII, SacII, and BamHI. The fragment pattern of the Tn3 segment present on the 7.2-kilobase gonococcal resistance plasmid, when compared to its known DNA sequence, allowed us to conclude that the HaeIII and BamHI resistance was due to modification of these sites. A comparison of the fragment pattern of the resistance plasmid, when isolated from Escherichia coli or Neisseria gonorrhoeae, revealed that the resistance of HaeII must also be due to modification of its recognition sequence. Isoschizomers of HaeII and HaeIII can be found in isolates of N. gonorrhoeae (NgoI and NgoII, respectively). A new restriction endonuclease in gonococci, NgoIII, with a specificity similar to SacII, is reported here. High-pressure liquid chromatography of gonococcal DNA showed the presence of 5-methylcytosine. It is suggested that the methylation of cytosine residues in the HaeII (NgoI), HaeIII (NgoII), and SacII (NgoIII) recognition sites is the basis for the resistance of gonococcal DNA to cleavage by these enzymes. This methylation may be part of a host restriction modification system. In two out of five gonococcal strains the sequence -GATC- was modified. One strain unable to modify this sequence was a spontaneous mutant of a strain carrying such a modifying function.

Base Sequence↗
PubMed1980

Cefuroxime treatment of urethritis caused by a beta-lactamase-producing strain of Neisseria gonorrhoeae.

A patient who contracted urethritis from a beta-lactamase-producing strain of Neisseria gonorrhoeae was successfully treated with the cephalosporin derivative cefuroxime. As expected, neither cefuroxime nor cefamandole was hydrolysed by plasmid-coded gonococcal beta-lactamase. Cefuroxime ought to be a valuable and efficacious substitute for penicillins in the treatment of gonhorrhoea due to beta-lactamase-producing gonococcal strains.

Adult↗
PubMed1979

Effect of colony type and pH on surface charge and hydrophobicity of Neisseria gonorrhoeae.

The effect of colonial variation and growth at pH 7.2 or pH 6.0 on the surface properties of Neisseria gonorrhoeae was assessed by the use of two-phase partitioning and hydrophobic interaction chromatography. Cells grown at pH 7.2 tended to be both hydrophobic and to possess a slight negative charge. Growth at pH 6.0 appeared to decrease hydrophobicity and to increase the negative surface charge. Possession of a series of outer membrane proteins, termed the colony opacity-associated proteins, did not appear to significantly affect charge or hydrophobicity. Piliated cells tended to have a higher negative charge than nonpiliated variants. They also tended to be less hydrophobic at pH 7.2, but became more hydrophobic at pH 6.0. The implications of these findings are discussed.

Bacterial Proteins↗
PubMed1979

Genetic exchange mechanisms in Neisseria gonorrhoeae.

There are two mechanisms for genetic exchange in Neisseria gonorrhoeae. Plasmid deoxyribonucleic acid can be transferred by conjugation, which is dependent on the presence of a 24.5-megadalton plasmid in the donor cell. We have shown that chromosomal deoxyribonucleic acid can be exchanged between all colonial variants by transformation, but not by conjugation. In the nonpiliated variants, however, this exchange was dependent on the presence of the 24.5-megadalton plasmid in the recipient cell.

Chromosomes, Bacterial↗
PubMed1979

Genetic basis for colonial variation in Neisseria gonorrhoeae.

When the piliated colony types of Neisseria gonorrhoeae, which predominate in recent isolates, were nonselectively subcultured in vitro, they gave rise to large numbers of nonpiliated, avirulent colonial variants. Evidence is presented to show that most of this variation occurs after active growth has ceased and that the variation is sensitive to the action of deoxyribonuclease. We suggest that this variation is a result of transformation. A second variation in colonial morphology involved differing levels of "colony opacity-associated proteins" in the outer membrane. This variation was also inhibited by the presence of deoxyribonuclease, but the genetic basis for it is not as yet clear.

Bacterial Proteins↗
PubMed1978

Contribution of a TEM-1-like beta-lactamase to penicillin resistance in Neisseria gonorrhoeae.

Two beta-lactamase-producing strains of Neisseria gonorrhoeae were studied. The substrate profile, molecular weight, and isoelectric point of their beta-lactamases were similar to those of the TEM-1 enzyme produced by many gram-negative bacilli. The gonococcal beta-lactamase was cell bound during exponential growth and was most likely located in the periplasm. Penicillin hydrolysis was efficient in intact cells, suggesting that the cell-bound beta-lactamase was freely accessible to benzylpenicillin. Both beta-lactamase-producing strains of N. gonorrhoeae contained an additional multicopy plasmid with a mass of 3.3 megadaltons (Mdal). A spontaneous penicillin-susceptible revertant lacked both beta-lactamase activity and the 3.3-Mdal plasmid, providing evidence for plasmid-mediated penicillin resistance. During a shift from GC medium to rich MOPS medium, growth of the penicillin-susceptible revertant in contrast to that of the plasmid-carrying strain was markedly impaired, suggesting a physiological effect due to the presence of the 3.3-Mdal plasmid.

DNA, Circular↗
PubMed1976

Septum formation-defective mutant of Escherichia coli.

Mutants of Escherichia coli defective in septum initiation, as well as in septum formation were obtained spontaneously, without mutagenic treatment, by selection of rifampin-tolerant mutants of an antibiotic-permeable strain carrying the envA mutation. The disturbed phenotype was in all mutants aggrevated the low incubation temperatures. One allele, sefA1, was studied in detail. Septum initiation, as well as septum formation, was promoted by high cell densities or by the addition of low concentrations of certain antibiotics, e.g., rifampin and chloramphenicol, to low-density cultures. The observed rifampicin depencence was studied in detail. These experiments indicated that a very modest shift-down situation suppressed the phenotype and enabled constrictions to proceed to cell separation. The rifampicin sensitivity of the partially purified deoxyribonucleic acid polymerase was not affected by the sefA1 allele, which is located close to proA and is thus distinct from envA. Growth parameters during the shift to 25 degrees C were followed in a transductant carrying HE SEFA1 allele. This constriction was characteristically blunt and did not lead to cell separation. At the time of formation of these frozen constrictions, clear zones representing a separation of wall from cytoplasmic membrane appeared. These polar tips did not inhibit expansion of the cell envelope. The phenotype of cells carrying the sefA1 allele suggests a disturbed relationship among protoplasm expansion, envelope growth, and septum formation. It is thought that the blunt constrictions observed are caused by an inability of the two septal peptidoglycan layers to fuse during an early stage of septation.

Cell Division↗
PubMedDate not supplied

The relationship of pain and suffering in a hospice population.

Although suffering is frequently encountered in the hospice setting, few studies examine this condition. The purpose of this study was to examine the relationship between terminally ill hospice patients' pain and their physical, spiritual, and personal or family suffering. Using a tool developed to measure suffering in those categories, a convenience sample of 92 patients were asked to rate their worst pain within the last 24 hours, and to rate their suffering at the time of the interview. All items were rated on a 0-10 Numeric Intensity Scale. Pain scores and suffering scores were divided into four categories; no pain or no suffering (0), mild pain or mild suffering (1-3), moderate pain or moderate suffering (4-6), and severe pain or severe suffering (7-10). Mean scores were compared for pain and suffering. More patients experienced suffering than pain. The highest mean suffering scores occurred in the severe pain category. Correlation coefficients for each suffering and pain category were also calculated. Results indicated a statistically significant correlation only between severe pain and suffering in the categories of loss of enjoyment of life, unfinished business, and concern for loved ones. Data indicated that patients view pain and suffering as separate entities. Further research is needed to better define the relationship between pain and suffering in order to improve assessment and intervention in a hospice setting.

Adult↗
PubMedDate not supplied

The ballet of baseball: lessons of the game for hospice.

As Yogi Berra once said, "The future ain't what it used to be." In the era of rapid change in health care, hospice and palliative care programs will survive only through organizational teamwork. Using the lessons of baseball, we present a stadium-eye perspective on how programs can take the three fundamentals of baseball--pitching, batting, and fielding--and translate them into the three fundamentals of organizational teamwork--clinical, operational, and financial. The best clinicians (pitchers) are of no use if the office operations (batting) keep the patients (fans) out of the stadium and no program can survive without the financial resources (fielding.) When you come to a fork in the road, take it.

Hospice Care↗