bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physical organization of mixed protease inhibitor gene clusters, coordinated expression and association with resistance to late blight at the StKI locus on potato chromosome III
Authors: ODENY DAMARIS ACHIENG , STICH BENJAMIN , GEBHARDT CHRISTIANE 
Published: August 2010

ABSTRACTProtease inhibitors (PIs) play a role in plant defence against pests and pathogens as well as in plant development. Potato (Solanum tuberosum) contains abundant levels of diverse PIs. Most potato Kunitz‐type inhibitor (KTI) genes map to the StKI locus on potato chromosome III, which is linked to a quantitative trait locus (QTL) for resistance to Phytophthora infestans. To elucidate the physical organization of PIs at the StKI locus, we screened bacterial artificial chromosome (BAC) libraries with KTI probes. Ten different clones were selected, sequenced and annotated. Of 100 putative genes, 22 corresponded to five PI classes. Expression analysis by quantitative real‐time PCR (qRT‐PCR) using PI class‐specific primers in different tissues of the tetraploid potato cultivars ‘Nikita’ and ‘Baltica’ revealed different transcript levels, depending on PI type and genotype. During the compatible interaction with a complex race of P. infestans, four PI classes showed coordinated expression over 3 d after infection, a strong decrease in infected leaves and a transient induction in systemic leaves. Basal transcript levels in non‐infected leaves differed strongly between the two genotypes examined. Two microsatellite markers located within the PI gene cluster were associated with resistance to P. infestans in a population of potato varieties and breeding clones.
Murine Bone Marrow Mesenchymal Stem Cells Cause Mature Dendritic Cells to Promote T‐Cell Tolerance
Authors: Wang Q. , Sun B. , Wang D. , Ji Y. , Kong Q. , Wang G. , Wang J. , Zhao W. , Jin L. , Li H. 
Published: August 2010

AbstractBone mesenchymal stem cells (BMSC) are attractive not only in regenerative medicine, but also for the treatment of autoimmune diseases and graft‐versus‐host disease. BMSC also play a role in enabling alloantigen tolerance. An in‐depth mechanistic understanding of this phenomenon of tolerance could lead to novel cell‐based therapies for autoimmune disease. We demonstrate here that co‐culture of mature dendritic cells (DC) with BMSC in a transwell system (BMSC‐DC) downregulated expression of the maturation marker, CD83 and CD80/86 co‐stimulatory molecules on DC, while increasing their endocytic activity. This resulted in defective antigen presentation and co‐stimulatory capacity of mature DC. Functionally, BMSC‐DC have impaired T‐cell stimulatory activity in a mixed lymphocyte reaction and orchestrate a shift from predominantly pro‐inflammatory T‐helper (Th)‐1 to anti‐inflammatory Th2 cells. While the expression of MHC II, CD80 and CD86 were upregulated on BMSC co‐cultured with DC, these BMSC lacked the ability to stimulate T‐cell proliferation. Taken together, these data suggest that the interaction between BMSC and DC modulates the immunoregulatory function of these cells in a coordinated manner, effectively skewing the immune response towards T‐cell tolerance.
Vitamin K‐dependent carboxylase
Authors: LARUE VALÉRY , GHARBI‐BENAROUS JOSYANE , ACHER FRANCINE , AZERAD ROBERT , GIRAULT JEAN‐PIERRE 
Published: August 2010

The conformational analysis of four glutamic acid analogues containing a cyclopentyl or cyclohexyl ring, substituted in position 1 by a Boc‐protected amino group and a methyl ester group and in position 3 by a free carboxylate group (6–9), has been carried out in an aqueous environment, by 1H and 13C NMR spectroscopy, and molecular dynamics (MD). These compounds have been shown to be weak competitive inhibitors (Ki≅ 20–65 mM) of the vitamin K‐dependent carboxylation of Boc‐Glu‐OMe in rat liver microsomes independently of their ring size and stereochemical features. However, the cyclic trans isomers have been found more active than the cis ones and Boc‐trans‐C5‐OMe (9) is the most potent inhibitor in the series (cis and trans isomers are defined by the relative arrangement of the carboxyl functions).Such cyclic glutamyl derivatives may provide valuable informations on the preferred bioactive conformations of synthetic glutamyl substrates at the active site of the carboxylase. In aqueous solution, the Boc‐cis‐ and trans‐C6 esters exhibit chair conformations with exclusively equatorial and axial substituent positions, while the Boc‐cis‐ and trans‐C5 compounds may display envelope E or ‘twist’ T conformations with the substituents in the following positions. equatorial, axial and isoclinal. For each compound, the conformations resulting from NMR and MD data were analyzed and classified according to the dihedral angles %1 and %2, the distances of functional groups, and the spatial charge distribution involving the free carboxyl group.A reduced number of conformational families were found to be in qualitative agreement with NMR and MD data. These results are discussed in relation with the carboxylase inhibitory activity of the analogues, and a spatial disposition of the glutamyl side chain that could be recognized by the carboxylase is deduced. © Munksgaard 1997.
Synthesis and antibacterial action of cecropin and proline‐arginine‐rich peptides from pig intestine
Authors: VUNNAM SATYANARAYANA , JUVVADI PADMAJA , MERRIFIELD R. B. 
Published: August 2010

Dedicated to Professor Koji Nakanishi on the occasion of his 70th birthday.Two antimicrobial peptides, cecropin P1 (CPl), with a C‐terminal carboxyl group, and PR‐39, with an amidated C‐terminus, are found in the small intestine of the pig. Each is active against both Gram‐positive and Gram‐negative bacteria. We have synthesized these peptides and several analogs, including the d‐enantiomers and the retro sequences, each with a free or acetylated amino terminus. The CPI amide was also prepared.The retro CP1 peptides were much less active than the parent CPl peptide, confirming the importance of sequence or the amide bond and helix dipole direction, and the Nα‐acetyl peptides were also less active, indicating that a free amino terminus is essential for high activity. The ratio of the lethal concentration of L/D isomers of CP1 is less than 1 for Gram‐negative, but greater than 1 for Gram‐positive bacteria. PR‐39 showed no significant chiral selectivity toward Escherichia coli, Bacillus subtilis and Streptococcus pyogenes, but the l/d ratio was high for Pseudomonas aeruginosa (66), and very high for Staphylococcus aureus (>1000). In the latter case the lethal concentration for the d‐isomer was 0.57 μ whereas this organism was quite resistant to the l‐isomer (>600μ). Thus the enantiomers of CP1 and PR‐39 are not equally active for all species. In a plate assay with a very small log‐phase inoculum of Staph. aureus, D‐PR‐39 produced a clear zone of killing surrounded by a zone of stimulated growth. After prolonged incubation the two zones became one clear zone. Addition of D‐PR‐39 to the wells of a dense turbid plate of growing cells showed a cleared zone for each of the test organisms, indicating that PR‐39 lyses the bacteria rather than simply inhibiting their multiplication. © Munksgaard 1997.
Palmitate and stearate binding to human serum albumin
Authors: VORUM HENRIK , FISKER KIM , HONORÉ BENT 
Published: August 2010

Multiple binding equilibria of two apparently insoluble ligands, palmitate and stearate, to defatted human serum albumin were studied in a 66 mM sodium phosphate buffer (pH 7.4) at 37 °C, by determination of dialytic exchange rates of ligands among identical equilibrium solutions.The experimental data were analysed by a computerised curve fitting procedure using equilibrium equations for multiple binding of ligands, containing relative binding constants, valid whether the ligands are truly insoluble or are slightly soluble and irrespective of aggregation in aqueous solution. A best‐fit set of relative binding constants was found, and subsequently 30 sets of acceptable constants for each set of data in order to evaluate the variation. The data were first fitted by the relative Scatchard's equation, then by the relative, stoichiometric equation. Scatchard's equation is deduced on the presumption that cooperativity is absent while the stoichiometric equation is valid even when cooperativity is present. It was found with palmitate as well as with stearate that the two equations fitted the data equally well, and it was concluded that the observations were compatible with absence of cooperativity. The relative Scatchard binding constants were converted to relative, stoichiometric constants and it was found that the variations of the latter were slight. © Munksgaard 1997.
Solution conformational analysis of amphiphilic helical, synthetic analogs of the lipopeptaibol trichogin GAIV
Authors: Monaco V. , Locardi E. , Formaggio F. , Crisma M. , Mammi S. , Peggion E. , Toniolo C. , Rebuffat S. , Bodo B. 
Published: August 2010

AbstractThe step‐by‐step synthesis by solution methods of the [Ser2,5,6,9, Leu‐OMe11] analog of trichogin GA IV is described. The four Ser residues have been incorporated into the sequence as replacements of the naturally occurring Gly residues to increase the amphiphilicity of the 3D‐structure of the lipopeptaibol. A detailed solution conformational analysis has been performed on this undecapeptide and its prototypical [Leu‐OMe11] trichogin GA IV analog using FTIR absorption and CD spectroscopies, and two‐dimensional NMR under a variety of experimental conditions, including a membrane‐mimetic environment. Both peptides adopt a mixed 310/α‐helical structure, which in the micellar system was found to be less flexible for the Ser‐containing analog. For both analogs permeability measurements revealed membrane‐modifying properties comparable to those of the natural lipopeptaibol.
A validation study of molecular descriptors for the rational design of peptide libraries
Authors: Matter H. 
Published: August 2010

AbstractImportant molecular descriptors used for establishing quantitative structure‐activity relationships are investigated to classify similar versus dissimilar peptides. When searching new lead structures, synthesizing and testing compounds which are too similar wastes time and resources. In contrast, any lead optimization program requires the investigation of similar compounds to that lead. Thus, it is important to maximize or minimize the structural diversity of peptides to design useful compound libraries for lead finding or lead refinement projects.If a molecular descriptor is a useful measure of similarity for the design of peptide libraries, small differences in this descriptor for a pair of molecules should only translate into small biological differences. Using this paradigm as a basis for descriptor validation, it was possible to rank different molecular descriptors. Those physicochemical descriptors are 2D fingerprints and five experimentally or theoretically derived principal property scales. Some theoretically derived metrics are obtained by computing interaction energies or similarity indices on predefined 3D grid points using canonical conformations for individual amino acids. The resulting 3D data matrices are analyzed using a principal component analysis leading to three principal properties for CoMFA (Comparative Molecular Field Analysis) or CoMSIA (Comparative Molecular Similarity Index Analysis) derived molecular fields.The descriptor validation results reveal the applicability of design tools on peptide data sets. Experimentally derived descriptors, in general, are more acceptable than computationally derived metrics, while the latter provide a statistically valid alternative to characterize novel building blocks. The CoMSIA metrics perform slighly better than the CoMFA‐based principal properties, while GRID‐based descriptors are always less acceptable.
1H‐NMR and CD studies on the structural transition of serum albumin in the acidic region—The N→F transition
Authors: Era S. , Sogami M. 
Published: August 2010

Abstract:Helical content (fα) of bovine mercaptalbumin (BMA) showed the characteristic two‐step decrease in the acidic region, one corresponding to the N→F transition (pH 4.40→3.75; fα, 0.68→0.58) and the other to the F→E transition (the acid‐expansion) (pH 3.60→2.90; fα, 0.58→0.48). However, fα of human serum albumin (HSA) mainly decreased in the N→F transition (N→F, pH 4.6→3.4; fα, 0.70→0.55 and F→E, below pH 3.0; fα, 0.55→0.52). The difference in pH‐profile of fα between BMA and HSA might be due to the microheterogeneity. The 1H‐NMR spectra and cross‐relaxation times (TIS) from irradiated to observed protein protons, which reflect the structural fluctuation and/or mobilability in proteins, were measured on the N‐, F‐, E‐forms of HSA and BMA, and the N*‐form (8.23 M urea, neutral pD) of iodoacetamide‐blocked HSA (IA‐HSA) and bovine serum albumin (IA‐BSA). The 1H‐NMR spectra and elongations of TIS values for the F‐ and E‐forms of HSA and the E‐form of BMA were quite similar to those for the N*‐form of IA‐HSA and IA‐BSA, indicating the liberation of the intramolecular motion in the F‐ and E‐forms. Those for the F‐form of BMA were intermediate between the N‐ and E‐form. The present results together with the reported data on hydrodynamic radii and D–H exchange reaction, indicate that the F‐form of HSA and presumably BMA has a native‐like globule form with a highly helical state and fluctuating tertiary structure. Thus, all of the present findings on the F‐form of serum albumin seem to be in accord with the structural features for the F‐form suggested by Foster's group (1‐3, 19, 20, 22, 23) and the molten globule state demonstrated by Dolgikh et al. (40), and Ohgushi and Wada (36, 37).
Creening of combinatorial peptide libraries: Identification of ligands for affinity purification of proteins using a radiological approach
Authors: Mondorf K. , Kaufman D.B. , Carbonell R.G. 
Published: August 2010

Abstract:Peptides deduced from peptide libraries may serve as affinity ligands for protein purification. Identification of a ligand that binds the protein of interest depends highly on the screening method used. One approach which offers simple and direct detection involves screening a solid‐phase peptide library against a radiolabeled target protein.We have developed a radiological screening method, using 14C as a radioactive label, that offers high resolution and sensitivity. Less than 100 DPM/bead are detectable after a one‐day exposure using autoradiography. The validity of the technique was illustrated by screening a solid‐phase hexameric‐peptide library spiked with YNFEVL‐beads against 14C‐labeled ribonuclease S‐protein. For this particular system, the amount of protein bound to a single bead was estimated to be in the femtomolar range with a peptide:protein ratio of 500:1.Finally, a portion of the library was screened against 14C‐labeled fibrinogen. Three peptides deduced from the library, WQEHYN, WQEHYN, and YENYGY, purified fibrinogen from a mixture with albumin.
Solid‐phase synthesis and on‐resin cyclization of a disulfide bond peptide and lactam analogues corresponding to the major antigenic site of HIV gp41 protein
Authors: Limal D. , Briand J.‐P , Dalbon P. , Jolivet M. 
Published: August 2010

Abstract:A cyclic peptide that spans the major antigenic determinant of the human immunodeficiency virus (HIV) glycoprotein 41 (gp41) has been synthesized according to various strategies. For immunodiagnostic applications, biotin was added at the N‐terminus of the peptide and aminohexanoic acid was used as a spacer. Polymer‐supported oxidations were carried out in a variety of ways with thallium (III) trifluoroacetate. The biotinylcyclic peptide was released from the support using trimethylsilyl trifluoromethane sulfonate and various scavengers. The efficacy of these different cyclization and cleavage procedures was compared. Side reactions were studied, and a simple and efficient procedure was set up to monitor peptide cyclization by mass spectrometry. In a second series of syntheses the disulfide bridge was replaced by an amide bond. For this purpose, an aspartic acid derivative and a diaminopropionic acid were introduced during the synthesis in place of the two cysteine residues in the parent sequence. On‐resin cyclization was performed and led to a major side‐product identified as a piperidide. This undesired base‐mediated side reaction was prevented when, instead of piperidine, 1,8‐diazabicyclo‐[5.4.0]undec‐7‐ene was used for fluorenylmethyl ester deprotection. Reactivity of these peptides with different patients'sera and with a monoclonal antibody directed against the whole gp41 was tested using an enzyme‐linked immunosorbent assay.
The asymmetric synthesis of arginine mimetics: derivatives of (S)‐2‐, 3‐ and 4‐amidinophenylalanine suitable for incorporation into enzyme inhibitors and/or peptides
Authors: Kent D.R. , Cody W.L. , Doherty A.M. 
Published: August 2010

AbstractThe specific inhibition of trypsin‐like serine proteases has become an important therapeutic target. These proteases have been implicated in several physiological and pathophysiological processes, including blood coagulation, digestion, and inflammation. Proteases of this class cleave polypeptide chains C‐terminal to a basic residue (arginine or lysine). It has been shown that selectivity for a particular serine protease can be conferred based upon the structural moiety incorporated in the P1, position. In this regard, the three isomers (ortho, meta, and para) of amidinophenylalanine represent modified arginine residues and are important synthetic targets. Herein, a convenient asymmetric synthesis of (S)‐Nα‐(tert‐butyloxycarbonyl)‐2‐, (S)‐Nα‐(tert‐butyloxycarbonyl)‐3‐, and (S)‐Nα‐(tert‐butyloxycarbonyl)‐4‐amidinophenyl‐alanine N,O‐dimethylamides (Weinreb amides) will be described. These derivatives represent key synthetic intermediates for the synthesis of enzyme inhibitors because the amidine can be readily orthogonally protected, while the Weinreb amide is easily converted to a variety of electrophilic carbonyls via reduction to the corresponding aldehyde or by reaction with various lithiated heterocycles. Likewise, the Weinreb amide can be reduced to the aldehyde and subsequently oxidized to the corresponding carboxylate, which is suitable for solid‐ or solution‐phase peptide synthetic strategies.
Prediction of post‐operative pain after a laparoscopic tubal ligation procedure
Authors: RUDIN Å. , WÖLNER‐HANSSEN P. , HELLBOM M. , WERNER M. U. 
Published: August 2010

Background: Pre‐operative identification of reliable predictors of post‐operative pain may lead to improved pain management strategies. We investigated the correlation between pre‐operative pain, psychometric variables, response to heat stimuli and post‐operative pain following a laparoscopic tubal ligation procedure.Methods: Assessments of anxiety, mood, psychological vulnerability and pre‐operative pain were made before surgery using the State‐Trait Anxiety Inventory (STAI), the Hospital Anxiety Depression Scale (HADS), a psychological vulnerability test and the Short‐Form McGill Pain Questionnaire (SF‐MPQ), respectively. Pre‐operative assessments of thermal thresholds and pain response to randomized series of heat stimuli (1 s, 44–48 °C) were made with quantitative sensory testing technique. Post‐operative pain intensity was evaluated daily by a visual analogue scale during rest and during standardized dynamic conditions for 10 days following surgery. Univariate and multivariate regression analyses were used to construct prediction models.Results: Fifty‐nine patients completed the study. Post‐operative pain was significantly correlated with pre‐operative pain (SF‐MPQ), heat pain perception, psychological vulnerability, STAI and HADS. In the multiple regression model pre‐operative pain and heat pain perception were significant predictive factors (R=0.537–0.609).Conclusion: The study indicates that pre‐surgical pain and heat pain sensitivity are important pre‐operative indicators of post‐operative pain intensity, while psychological factors like vulnerability and anxiety seem to contribute to a lesser degree after laparoscopic tubal ligation. The prediction model accounted for 29–43% of the total variance in post‐operative movement‐related pain.
Stoffwechselversuche an Schweinen mit künstlich getrocknetem Rübenkraut und mit Molkeneiweiß unter Berücksichtigung des Einflusses auf den Säurebasenhaushalt
Authors: Lenkeit W. , Becker M. , Lagneau E. 
Published: August 2010

Zusammenfassung

Beim Schwein tritt nach den durchgeführten Versuchen der Ein‐fluß der Trocknungsart des Rübenkrautes auf dessen Verdaulichkeit nicht so deutlich hervor wie beim Schaf und Geflügel. Im trommelgetrockneten Rübenkraut wurde eine Verdaulichkeit des Eiweißes von 44,11% ge‐funden, im umlaufgetrockneten von 40,45 %.
Im getrockneten Molkeneiweiß wurde das Rohprotein zu 91,10% verdaut. Das Verhältnis Ca: P beträgt 37,3: 1 Äquivalente.
Getrocknetes Rübenkraut und Luzernemehl verschieben das Säure‐Basenverhältnis im Harn nach der basischen Seite, Molkeneiweiß und Gerstenschrot nach der sauren Seite. Auf diese Futterwirkungen wird kurz eingegangen.
Über den Futterwert von Süßlupinentrockengut
Authors: Nehring K. , Schramm W. , Malkomesius Ph. 
Published: August 2010

Zusammenfassung der ErgebnisseEs wurden Untersuchungen über den Futterwert von getrocknetem Süßlupinengrünfutter, das nach dem Rema‐Rosin‐Verfahren gewonnen war, durchgeführt. Die Ergebnisse waren folgende:

Das Süßlupinentrockengut wies einen Wassergehalt von 10,1 % und einen Rohproteingehalt von 18,3% auf. Der Rohfasergehalt betrug 22,4%.
In Ausnützungsversuchen an Hammeln wurde eine Verdaulichkeitder organischen Substanz von … 72,2 %des Rohproteins von… … 64,5 %festgestellt. Daraus errechnete sich der Gehalt anverdaulichem Rohprotein zu … 11,8%Stärkewert… … … 45,0
In einem Milchviehfütterungsversuch konnte die Hälfte des Kraftfutters durch das getrocknete Süßlupinengrünfutter ersetzt werden, ohne daß die Leistung beeinträchtigt wurde. Hinsichtlich des Fettgehalts war sogar eine geringe Erhöhung unter dem Einfluß des Trockenguts zu beobachten.
Auch bei einem Mastversuch mit Lämmern, bei dem die Hälfte des Kraftfutters durch das Trockengut ersetzt wurde, war das Ergebnis ein günstiges. Die tägliche Zunahme in der Gruppe mit dem getrockneten Süßlupinengrünfutter lag mit 253 g je Tag sogar etwas höher als in der Kraftfuttergruppe mit 219 g je Tag.