Den vanligaste formen av forskarutbildning i Sverige innebar att doktorand och handledare forskar och publicerar tillsammans inom ett projekt som utformats av handledaren. Forskningsprojektet och doktorandens studiefinansiering bekostas oftast med handledarens forskningsmedel. Dessa omstandigheter forekommer framforallt inom medicin, naturvetenskap och teknik men aterfinns allt oftare inom andra omraden, som konsekvens av bland annat de krav om full studiefinansiering som infordes i Hogskoleforordningen 1998 samt att forskning och forskarutbildning genom svensk forskningspolitik i okande grad finansieras med externa forskningsmedel vunna i konkurrens. Granserna mellan utbildning och forskning respektive handledarskap och projektledarskap ar i dessa utbildningssammanhang diffusa eller upplosta vilket kan vara bade positivt och negativt for utbildningen och doktoranden. A ena sidan ar doktorandens arbete av stor vikt for handledarna och ovriga inom forskningsgemenskapen och doktoranden kan gradvis skolas in i forskarrollen inom ett projekt som sannolikt bade ar av hog kvalitet och har goda utsikter att lyckas. A andra sidan innebar placeringen inom forskningen att utbildningens och doktorandens behov riskerar att komma i skymundan for andra prioriteringar och mal, vilket kan hamma doktorandens utveckling till sjalvstandig forskare. Vi bedriver sedan en tid ett forskningsprojekt om forskarutbildningen och handledningen vid Medicinska fakulteten vid Lunds universitet. I likhet med andra medicinska fakulteter i landet, har har en mycket stor forskarutbildningsverksamhet (ca 1200 doktorander) byggts upp med hjalp av extern forskningsfinansiering och vi ar intresserade av hur denna omstandighet paverkar forskarutbildningen. Vara data bestar av oppet tillganglig information om fakulteten, dess forskning och forskarutbildningen, regler och riktlinjer, samt intervjuer med handledare, doktorander samt ansvariga for forskarutbildningen. Vi anlagger ett systemperspektiv och anvander aktivitetsteori (Engestrom, 1987) som ramverk for var analys, som bland annat sker genom deduktiv kvalitativ innehallsanalys (Elo & Kyngas, 2008). I denna presentation kommer vi att redogora for resultat kopplade till handledarintervjuerna. Handledarnas huvudsakliga fokus (objekt) ar doktorandernas forskning men denna tillskrivs olika innebord och ses som medel antingen for handledarens egen forskningsproduktion och akademiska avancemang, for det lokala forskningsfaltets och forskningsgemenskapens utveckling och regenerering, eller for larande och kvalitetssakring inom utbildningen. Doktoranden beskrivs som en allt mer sjalvgaende arbetare inom forskningsproduktionen, en junior medforskare som bidrar till projektets design och utveckling och som gradvis forvantas overta ansvaret, eller en student som skall lara sig att forska genom att delta i forskningsprocessen med stod av handledning och utbildningsinslag. Handledarna ger ocksa en varierande bild av vilka inslag i forskningsprocessen (verktyg) doktoranden ges tilltrade till och inflytande over. Aktivitetsteorins regelelement aterfinns dels i form av formella regler och riktlinjer relaterade till utbildningsregleringen och dels som tvingande omstandigheter och villkor inom forskningen. Det finns flera exempel pa hur de forsta reglerna anpassats efter de sistnamnda.Vara preliminara resultat visar flera exempel pa spanningar, motsattningar och anpassningar inom forskarutbildningen vilka kan relateras till forskningens forandrade villkor. Flera av dessa ar problematiska och vi menar att de senaste decenniernas forskningspolitik innebar en stor utmaning for forskarutbildningen med potentiella konsekvenser for den framtida akademin och for forskningen sjalv. (Less)

Uppsatsen behandlar ett foretags satsning pa forskning och utveckling och dess samband med aktieavkastningen. En tidigare studie visar pa att ett sadant samband existerar. I var studie undersoks den svenska halsovardsbranschen mellan 1997 och 2003. Forst analyserades urvalet; karaktaristiken hos foretagen indikerade pa ett negativt samband mellan forskning och utveckling och aktieavkastning. Foretag inom halsovardsbranschen med stor satsning pa forskning och utveckling har samre aktieavkastning an foretag med lag satsning. Darefter genomfordes en omfattande regressionsanalys for att prova hypotesen att satsningen pa forskning och utveckling har samband med aktieavkastningen. Signifikansnivaerna i regressionerna ar dock for laga for att kunna faststalla nagot samband. Saledes ar slutsatsen att det inte finns nagot samband mellan satsningar pa forskning och utveckling och aktieavkastning.

The cortical microtubules determine how cellulose microfibrils are deposited in the plant cell wall and are thus important for the control of cell expansion. To understand how microtubules can control microfibril deposition, the components that link the microtubules to the plasma membrane (PM) of plant cells must be isolated. To obtain information on the properties of the tubulin-membrane associations, cauliflower (Brassica oleracea) PM was subjected to Triton X-114 fractionation, and the distribution of alpha- and beta-tubulin was analyzed using immunoblotting. Approximately one-half of the PM-associated tubulin was solubilized by Triton X-114 and 10 to 15% of both alpha- and beta-tubulin was recovered in the detergent phase (indicative of hydrophobic properties) and 30 to 40% was recovered in the aqueous phase. The hydrophobic tubulin could be released from the membrane by high pH extraction with preserved hydrophobicity. A large part of the PM-associated tubulin was found in the Triton-insoluble fraction. When this insoluble material was extracted a second time, a substantial amount of hydrophobic tubulin was released if the salt concentration was increased, suggesting that the hydrophobic tubulin was linked to a high-salt-sensitive protein aggregate that probably includes other components of the cytoskeleton. The hydrophobicity of a fraction of PM-associated tubulin could reflect a direct or indirect interaction of this tubulin with the lipid bilayer or with an integral membrane protein and may represent the anchoring of the cortical microtubules to the PM, a key element in the regulation of cell expansion.

The lipid A and lipopolysaccharide (LPS) binding and neutralizing activities of a synthetic, polycationic, amphiphilic peptide were studied. The branched peptide, designed as a functional analog of polymyxin B, has a six residue hydrophobic sequence, bearing at its N-terminus a penultimate lysine residue whose α- and E-amino groups are coupled to two terminal lysine residues. In fluorescence spectroscopic studies designed to examine relative affinities of binding to the toxin, neutralization of surface charge and fluidization of the acyl domains, the peptide was active, closely resembling the effects of polymyxin B and its nonapeptide derivative; however, the synthetic peptide does not induce phase transitions in LPS aggregates as do polymyxin B and polymyxin B nonapeptide. The peptide was also comparable with polymyxin B in its ability to inhibit LPS-mediated IL-1 and IL-6 release from human peripheral blood mononuclear cells. The synthetic compound is devoid of antibacterial activities and did not induce conductance fluxes in LPS-containing asymmetric planar membranes. These results strengthen the premise that basicity and amphiphilicity are necessary and sufficient physical properties that ascribe endotoxin binding and neutralizing activities, and further suggest that antibacterial/membrane perturbant and LPS neutralizing activities are dissociable, which may be of value in designing LPS-sequestering agents of low toxicity.

The potential of artificial feed forward neural networks in assessing the detection of Mycobacterium tuberculosis, its antibiotic resistance, and the pathogenicity of 19 Mycobacterial species was tested with a set of 67 strains based on signature lipid analysis. The lipid signature biomarkers were based on concentration patterns of 36 wax neutral lipid alcohols and fatty acids which to date are found exclusively in Mycobacteria. The strains were assigned to species by independent clinical laboratories by their cultural properties and in some cases on the basis of DNA gene probes. The trained artificial neural network was able to identify correctly M. tuberculosis strains from their lipid signatures using one hidden node. The predictive accuracy was independently tested with 10 lipid profiles not used to train the artificial neural network. The analysis of predictive sensitivity showed that most of M. tuberculosis lipid signature is separable from other Mycobacterium spp. based on these data. Recognition of antibiotic resistance and pathogenicity was non-linear requiring multiple hidden nodes. When the same data set was used to train an artificial neural network with two hidden nodes to recognize different nutritional behaviours, pathogenic and saprotrophic Mycobacterium spp. were successfully recognized with 5% and 4% error respectively. The successful recognition of strict pathogenicity teas more complex requiring a hidden layer of 23 nodes. An association between the lipid signatures of 15 strains of Mycobacterium tuberculosis with resistance to isoniazid and streptomycin was achieved with a 7% error by a artificial neural network with 13 hidden nodes. These results suggest that the analysis of signature lipids by artificial neural network can be used for species detection/identification, pathogenicity, and drug resistance. Since signature lipid biomarker analysis does not require isolation and culture of microbes, has the potential for automation, rapid analysis, and exquisite sensitivity, the technique offers great promise in the detection and management of Mycobacterial disease.

The lipopolysaccharide (LPS, endotoxin) of Legionella pneumophila serogroup 1 (Philadelphia 1) exhibits peculiar chemical features which may account for its importance as a bacterial virulence factor. The O-chain of this LPS constitutes a homopolymer of an unusual sugar, 5-acetamidino-7-acetamido-8-O-acetyl-3,5,7, 9-tetradeoxy-D-glycero-L-galacto-nonulosonic acid (legionaminic acid) of which about 10-75 residues are present. Due to the lack of free hydroxyl groups, this homopolymer renders the cell surface highly hydrophobic and, therefore, supports adherence to the membrane of target cells including alveolar macrophages. Investigations of the serological specificity of the serogroup 1 LPS revealed a monoclonal antibody (mAb 3/1) which recognizes an epitope located in the environment of the 8-O-acetyl group of legionaminic acid. According to epidemiological studies, this determinant appears to be associated with L. pneumophila virulence. The outer core oligosaccharide of L. pneumophila LPS exhibits also hydrophobic properties due to the presence of N- and O-acetyl groups as well as 6-deoxy sugars. The inner core expresses both similarities and differences as compared to enterobacterial core oligosaccharides in containing Kdo but lacking heptose and phosphate groups. Lipid A possesses some unique structural features since its backbone consists of a bisphosphorylated beta-GlcpN3N-(1-->6)-GlcpN3N disaccharide with only amide-linked acyl groups having 14-22 carbon atoms. Long chain fatty acids [28:0(27-oxo) and 27:0-dioic] possessing the double length as enterobacterial acyl groups, may be responsible for the low endotoxicity of L. pneumophila lipid A.

Lipopolysaccharides (LPS) from Legionella israelensis, L. maceachernii and L. micdadei were analysed for chemical composition. The main sugar of the lipid A fractions was in each case 2,3-diamino-2,3-dideoxy-D-glucose. Lipid A of L. israelensis also contained a substantial amount of D-glucosamine. In each lipid A fraction a complex fatty acid pattern was detected. This comprised at least 19 different 3-hydroxy fatty acids (amide-linked), three 2,3-dihydroxy fatty acids (amide-linked), non-hydroxy fatty acids (ester-linked) as well as long-chain (omega-1)-oxo, (omega-1)-hydroxy and (1,omega)-dioic fatty acids (ester-linked). In addition, L. maceachernii and L. micdadei contained alpha-hydroxylated long-chain (omega-1)-oxo and (1,omega)-dioic fatty acids. The polysaccharide parts of L. maceachernii and L. micdadei LPS were similar and contained mainly L-rhamnose, L-fucose, D-mannose, D-glucose, L-fucosamine, D-glucosamine, 2-keto-3-deoxy-octonic acid (Kdo) as well as the rare octose yersiniose A. The corresponding composition of L. israelensis LPS was simpler and consisted mainly of L-rhamnose and 3-amino-3,6-dideoxy-D-mannose. LPS of L. israelensis and L. micdadei contained, in addition, 2-keto-octonic acid linked to Kdo. Phosphorylated sugar constituents were detected in all three LPS, whereas ethanolamine was found only in LPS from L. maceachernii. The SDS-PAGE band pattern of L. micdadei differed from the two others in a higher proportion of the low molecular mass constituents.

Biologia plantarum, an international journal for experimental botany founded in 1959 by Professor Bohumil Němec. Covers all branches of experimental botany ranging from molecular biology and biotechnology to whole-plant and stand functioning.

Alginate is a viscous extracellular polymer produced by mucoid strains of Pseudomonas aeruginosa that cause chronic pulmonary infections in patients with cystic fibrosis. Alginate is polymerized from GDP-mannuronate to a linear polymer of beta-1-4-linked residues of D-mannuronate and its C5-epimer, L-guluronate. We previously identified a gene called algG in the alginate biosynthetic operon that is required for incorporation of L-guluronate residues into alginate. In this study, we tested the hypothesis that the product of algG is a C5-epimerase that directly converts D-mannuronate to L-guluronate. The DNA sequence of algG was determined, and an open reading frame encoding a protein (AlgG) of approximately 60 kDa was identified. The inferred amino terminus of AlgG protein contained a putative signal sequence of 35 amino acids. Expression of algG in Escherichia coli demonstrated both 60-kDa pre-AlgG and 55-kDa mature AlgG proteins, the latter of which was localized to the periplasm. An N-terminal analysis of AlgG showed that the signal sequence was removed in the mature form. Pulse-chase experiments in both E. coli and P. aeruginosa provided evidence for conversion of the 60- to the 55-kDa size in vivo. Expression of algG from a plasmid inan algG (i.e., polymannuronate-producing) mutant of P. aeruginosa restored production of an alginate containing L-guluronate residues. The observation that AlgG is apparently processed and exported from the cytoplasm suggested that it may act as a polymer-level mannuronan C5-epimerase. An in vitro assay for mannuronan C5 epimerization was developed wherein extracts of E. coli expressing high levels of AlgG were incubated with polymannuronate. Epimerization of D-mannuronate to L-guluronate residues in the polymer was detected enzymatically, using a L-guluronate-specific alginate lyase of Klebsiella aerogenes. Epimerization was also detected in the in vitro reaction between recombinant AlgG and poly-D-mannuronate, using high-performance anion-exchange chromatography. The epimerization reaction was detected only when acetyl groups were removed from the poly-D-mannuronate substrate, suggesting that AlgG epimerization activity in vivo may be sensitive to acetylation of the D-mannuronan residues. These results demonstrate that AlgG has polymer-level mannuronan C5-epimerase activity.

Lipopolysaccharides (LPS) from Legionella feeleiiserogroup 1, L. hackeliaeserogroup 1 and L. jordaniswere subjected to chemical analysis. All three LPS contained D-mannose, D-glucose, D-glucosamine, L-glycero-D-manno-heptose, 2-keto-3-deoxyoctonic acid and glycerol. In addition the LPS of L. feeleiiwas characterized by L-quinovose (tentatively identified) and L-fucosamine, L. hackeliaeLPS by D-quinovosamine, D-galactosamine and D-galacturonic acid, and L. jordanisLPS by D-quinovosamine. Phosphorylated sugars were detected in all three LPS. The backbone sugar of the lipid A part was in each case 2,3-diamino-2,3-dideoxy-D-glucose substituted with a complex pattern of fatty acid, including 20-22 different amide-linked (non-branched and methyl-branched) 3-hydroxy fatty acids of chain-length ranging from 12 to 23 carbon atoms. The fatty acid patterns included also ester-linked nonhydroxylated entities and the uncommon 27-oxo-octacosanoic acid and 29-oxotriacontanoic acid. The LPS of L. hackeliaeand L. jordanisalso contained heptacosane-1,27-dioic and nonacosane-1,29-dioic acid, and their 2-hydroxy analogues were characteristic of L. jordanisLPS. SDS-PAGE patterns of the three LPS were distinctly different. Both L. feeleiiand L. jordanisproduced smooth-form LPS with characteristic ladder patterns, whereas L. hackeliaeLPS were of more rough-type character.

Twenty-nine species (76 strains) of members of the genus Legionella were analyzed for their cellular hydroxylated fatty acids (OH-FAs). The individual patterns were unusually complex and included both monohydroxylated and dihydroxylated chains of unbranched or branched (iso and anteiso) types. Comparison of the strain profiles by SIMCA (Soft Independent Modelling of Class Analogy) principal component analysis revealed four main groups. Group 1 included Legionella pneumophila plus L. israelensis strains, and group 2 included L. micdadei and L. maceacherneii strains. These two closely related groups were characterized by the occurrence of di-OH-FAs and differed mainly in the amounts of 3-OH-a21:0, 3-OH-n21:0, 3-OH-n22:0, and 3-OH-a23:0. Group 3 (13 species) was distinguished by i14:0 at less than 3%, 3-OH-3-OH-n14:0 at greater than 5%, 3-OH-n15:0 at greater than 2%, and minute amounts of OH-FAs with chains longer than 21:0. Group 4 (12 species) was heterogeneous. Its main characteristics were the presence of 3-OH-n12:0 and 3-OH-n13:0, 3-OH-i14:0 at greater than 5%, as well as significant amounts of 3-OH-a21:0 and 3-OH-n21:0. The groupings obtained by OH-FA profiles were found to reflect DNA-DNA homology groupings reasonably well, and the profiles appear to be useful for differentiation of Legionella species.

Four long-chain fatty acids, 2-hydroxy-27-oxo-octacosanoic acid (n28:0(2-OH,27-oxo)), 2-hydroxy-29-oxo-triacontanoic acid (n30:0(2-OH,29-oxo)), 2-hydroxy-heptacosane-1,27-dioic acid (27:0(2-OH)-dioic) and 2-hydroxy-nonacosane-1,29-dioic acid (29:0(2-OH)-dioic) were identified by GLC-MS analysis in the phenol-chloroform-petroleum ether (PCP) extracts of Legionella jordanis, L. maceachernii and L. micdadei indicating that they are constituents of lipopolysaccharide. Moreover, five long-chain fatty acids (28:0(27-OH), 28:0(27-oxo), 30:0(29-oxo), 27:0-dioic and 29:0-dioic) previously identified in L. pneumophila (Moll, H. et al., FEMS Microbiol. Lett., 97 (1992), 1-6) were also found in these species. This is to our knowledge the first report on the existence of long chain 2-hydroxylated (omega-1)-oxo fatty acids and 2-hydroxylated 1,omega-dioic fatty acids.