bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioactive glass particulate material as a filler for bone lesions
Authors: SCHEPERS E. , CLERCQ M. DE , DUCHEYNE P. , KEMPENEERS R. 
Published: August 2010

SummaryCalcium‐phosphate ceramic particulates are often used as filler material for enhanced repair of dental bone defects. Although evidence of bone ingrowth in the scaffold of these particles has been described, it is not observed consistently. Fibrous tissue often encapsulates these particles, which can subsequently become dispersed into the surrounding tissues or even exfoliated. The aim of the present study was to evaluate bioactive glass granules (Biogran ™)* as a filler for osseous lesions, and to compare them with two commercially available Hydroxylapatite (HA) granules. The particulates were implanted in the jaws of five beagle dogs, resected and evaluated after 1, 2, 3, 6 and 12 months of implantation. Histological analysis revealed an improvement in repair of all the lesions. A massive osteoconductive bone growth was seen near the walls of the bony cavities, but in greater amounts around the bioactive glass granules than around the HA materials. On top of this massive growth a trabecular bone growth was observed in the centre of the bony cavities. These trabeculae were associated with the glass particles, which exhibited osteophilic properties, while fibrous tissue separated the bone tissue from the HA particles. The centres of many of the particles are excavated, and are subsequently filled by newly formed bone tissue. This internally formed bone tissue is not necessarily connected to the surrounding bone tissue, and functions as a nucleation site for further bone repair. For the mesenchymal cells within the eroded glass particles this inner environment acts as a stimulus to differentiate into osteoblasts and to start their osteogenetic potential. This phenomenon was not observed around the HA materials. If the latter were surrounded by fibrous tissue, disintegration of the surface by giant cells was observed.
Occlusal abnormalities, pericranial muscle and joint tenderness and tooth wear in a group of migraine patients
Authors: STEELE J.G. , LAMEY P.J. , SHARKEY S.W. , SMITH G. McR. 
Published: August 2010

SummarySeventy‐two migraine sufferers, whose attacks normally begin during or soon after waking from sleep, were compared with 37 age‐ and sex‐matched controls to establish whether signs of mandibular dysfunction, occlusal discrepancies and known clenching or grinding habits were any more frequent among the former group. Temporomandibular joint tenderness or pain history, masticatory muscle tenderness and known clenching or grinding habits were found to occur at significantly increased levels in the migraine sufferers, with two‐thirds of these patients reporting a parafunctional habit. Occlusal abnormalities, including non‐working side or protrusive interferences and slides of > 1 mm to the intercuspal position, were found to occur at similar frequencies in the two groups. Assessment of wear of the occlusal surfaces also showed no difference, suggesting that any nocturnal habit with a role in migraine is more likely to be clenching in nature. In conclusion, evidence was found to support an aetiological role for nocturnal tooth clenching or grinding in migraine characterized by attacks that start predominantly during sleep or soon after waking, but no evidence of a link with occlusal factors was found in these oatients.
Longitudinal study on forces transmitted from denture base to retainers of lower free‐end saddle dentures with Aker's clasps
Authors: OGATA K. , SHIMIZU K. 
Published: August 2010

SummaryThe aim of this study was to make a longitudinal analysis of the forces transmitted from denture base to retainers of lower free‐end saddle dentures with Aker's clasps using a newly developed transducer. The experimental apparatus consisted of two components, a metal framework and a denture base embedded with a force‐detecting unit. This device was the transducer, which could detect changes in lateral and vertical forces transmitted from denture base to retainers at the same time. Forces were measured on several separate occasions from the insertion of new dentures to about 4 months afterwards. The result are summarized as follows: (i) the maximal mean value of vertical forces transmitted from denture base to retainers was decreased after 1 week of insertion of new dentures, then increased and reached a constant level (about ION) 4–6 weeks after the insertion of new dentures; (ii) there were large differences in the maximal mean value of lateral forces between subjects.
Heats of reactions between dentine bonding agents and tooth components
Authors: MUELLER H.J. , BAPNA M.S. , FAN P.L. 
Published: August 2010

SummaryThe heat of reaction of dentine bonding agents alone and dentine bonding agents with dentine, hydroxyapatite and collagen were measured using a differential scanning calorimeter (DSC) in the isothermal mode. The bonding agents were Scotchbond® and Panavia Ex® adhesives, and GC Fuji‐II glass ionomer cement. The heat of reaction for Scotchbond® and Panavin Ex® bonding adhesives were 44.3 and 6.9 mcal/mg, respectively. Furthermore, results support the view that the glass ionomer cements adhere to tooth structure by chemical bonding.
IL‐17 and Regulatory Cytokines (IL‐10 and IL‐27) in L. braziliensis Infection
Authors: NOVOA R. , BACELLAR O. , NASCIMENTO M. , CARDOSO T. M. , RAMASAWMY R. , OLIVEIRA W. N. , SCHRIEFER A. , CARVALHO E. M. 
Published: August 2010

AbstractCutaneous leishmaniasis (CL) is characterized by high production of pro‐inflammatory cytokines and development of pathology. Individuals with subclinical L. braziliensis infection (SC) have a positive skin test to leishmania, but do not develop disease. We evaluated whether the downregulation of inflammatory response in SC is mediated by IL‐10 and IL‐27 and whether IL‐17 is associated with control of infection. Participants include SC individuals, patients with CL and healthy subjects. Cytokines protein and mRNA were detected by ELISA and real‐time PCR. IFN‐γ and TNF‐α levels were higher in CL than in SC group. The IL‐10 levels and mRNA for IL‐10 were similar in both SC and CL. mRNA for IL‐27 was increased in cells from SC after stimulation with L. braziliensis antigen. There was a tendency for increased levels of IL‐17 in SC compared to CL. The weak type 1 immune response observed in SC L. braziliensis infection is not because of the regulatory effects of IL‐10 and IL‐27. The control of Leishmania infection may be mediated by innate immune response with participation of IL‐17. The results from this pilot study warrant further larger studies to investigate the potential contributions of IL‐17 and IL‐27 to the control of L. braziliensis infection.
Expression Pattern of Immune Suppressive Cytokines and Growth Factors in Oesophageal Adenocarcinoma Reveal a Tumour Immune Escape‐promoting Microenvironment
Authors: Milano F. , Jorritsma T. , Rygiel A. M. , Bergman J. J. , Sondermeijer C. , Ten Brinke A. , vanHam S. M. , Krishnadath K. K. 
Published: August 2010

AbstractImmunotherapy for solid cancers, such as oesophageal adenocarcinoma (OAC), is generally hampered by an unfavourable immunological tumour microenvironment. This prompted us to investigate the nature of the OAC environment. Biopsies of tumour and normal control tissues were collected from 17 OAC patients, and investigated using fluorescent immunohistochemistry (IHC) for the expression of cyclooxygenase‐2 (COX‐2), vascular endothelial growth factor (VEGF), transforming growth factor‐β, indoleamine 2–3 dioxygenase, CXCL3 and CXCR1, and for measuring a panel of cytokines by cytometric bead array (CBA), and for Granzyme B (GrB), Perforin and PI9 detection by semi‐quantitative PCR (QPCR). IHC showed that expression of all the above‐mentioned factors is upregulated in 80–93% of the tumours. By QPCR, the cytokine interleukin (IL)‐8 was significantly upregulated in tumour samples (P < 0.05). IL‐6, IL‐10, GrB and Perforin did not show any significant difference between normal and tumour samples, whereas PI9 levels were significantly higher in normal when compared with the tumour samples. CBA confirmed upregulation of IL‐8 and show upregulation of IL‐1β in the tumours (P < 0.05). Regarding IL‐6 and interferon (IFN)‐γ, no significant differences were observed between normal and tumour tissues. The OAC microenvironment is characterized by a lack of cytokines and factors that normally would enhance anti‐cancer responses, such as IFN‐γ and GrB, and by a high expression of several immuno‐suppressive factors, such as COX‐2, VEGF and IL‐8. For future improvement of treatment efficacy of OAC patients, it will be of importance to combine immunotherapy with immune‐modulating agents.
Synthesis and study of normal, enantio, retro, and retroenantio isomers of cecropin A‐melittin hybrids, their end group effects and selective enzyme inactivation
Authors: VUNNAM SATYANARAYANA , JUVVADI PADMAJA , ROTONDI KENNETH S. , MERRIFIELD R. B. 
Published: August 2010

In our effort to understand the structural requirements for the antimicrobial activity of cecropin A (CA) and melittin (M), we synthesized the normal, enantio, retro and retroenantio hybrid analogs; we related activity to their sequence, chirality, amide bond direction (helix dipole) and end group charges. To compare the effect of the end groups, each of these analogs was synthesized both with an acid and an amide C‐terminus and also with and without an Nα‐acetyl N‐terminus.The all‐l‐ and all‐d‐enantiomers of several cecropin‐melittin hybrids were previously found to be equally potent against several bacterial species, and no chiral effect was observed. This general rule has now been confirmed and extended. However, two exceptions have been found. All‐l‐CA(1‐13)M(1‐13) acid was 5 times and 9 times less potent than the all‐d‐analog, respectively, toward Gram‐positive Staphylococcus aureus and Gram‐negative Pseudomonas aeruginosa. A11‐l‐CA(1‐7)M(2‐9) acid was 5 times and 14 times less active against S. aureus and P. aeruginosa, respectively, than its all‐d acid isomer. The corresponding d‐ and l‐retro analogs differed only marginally. A role for proteolytic enzymes has been implicated as a cause for these differences in the activities of l‐ and d‐enantiomers. In all cases, blocking the α‐amine by acetylation had no significant effect on potency.The retro and retroenantio analogs of CA(1‐13)M(1‐13) acid were as potent as their normal and enantio analogs against all the test bacteria. The C‐terminal amides also showed similar potency against four test bacteria. It should be noted that the negative end of the helix dipole of a normal peptide points toward the C‐terminus, whereas it points away in the case of a retro derivative when viewed in the direction of the normal sequence.
Molecular recognition of cobalt(III)‐ligated peptides by serine proteases: The role of electrostatic effects
Authors: Bagger S. , Wagner K. 
Published: August 2010

AbstractA series of peptides with a positively charged cobalt(III)‐complex group attached to the carboxylate terminal was synthesized. The behavior of these metallopeptides as acceptor nucleophiles in acyl transfer reactions catalyzed by the three serine proteases bovine pancreatic α‐chymotrypsin, porcine pancreatic trypsin, and proteinase K from Tritirachium album was examined. The efficiency of the substrates was assessed by kinetic measurement of the partition between aminolysis and hydrolysis. The results are discussed with special reference to coulombic interactions between the metal‐ligated substrates and charged residues on the enzyme surfaces. The idea of using the metallopeptides in practical enzymatic peptide synthesis is put forward.
Role of conformational constraints of position 7 of the disulphide bridge of h‐α‐CGRP derivatives in their agonist versus antagonist properties
Authors: Saha S. , Waugh D.J.J. , Zhao P. , Abel P.W. , Smith D.D. 
Published: August 2010

Abstract:Previous structure‐activity studies have shown that the disulphide bridge of calcitonin gene‐related peptide (CGRP) is important for the highly potent, CGRP receptor‐mediated effects of this peptide. In this study penicillamine (Pen) was substituted for one or both of the cysteinyl residues to determine conformational and topographical properties of the disulphide bridge favourable for binding to CGRP receptors and/or receptor activation. Pen constrains the conformational flexibility of disulphide bridges in other peptides. Binding affinities were measured using a radioligand binding assay with membranes prepared from pig coronary arteries and125l‐h‐α‐CGRP. Functional effects were characterized using a previously reported pig coronary artery relaxation bioassay. The binding affinity of (Pen125]‐h‐α‐CGRP was not significantly different from that of h‐α‐CGRP. All other analogues showed reduced affinity for CGRP receptors. [Pen2)‐h‐α‐CGRP also caused relaxation of coronary arteries. The remaining analogues either caused relaxation with significantly reduced potency or failed to relax the arteries at concentrations up to 1 × 10‐−5M. All analogues that did not relax coronary arteries contained a D‐Pen in position 7 and inhibited CGRP‐induced relaxation. [D‐Pen2,7]h‐α‐CGRP was the most potent antagonist with aKB, value of 630 nM. This affinity is similar to that of the classical CGRP receptor antagonist, h‐α‐CGRP(8‐37), on these arteries (KB, 212 nM). These studies show that modifying the topography of the disulphide bridge can cause large and variable effects on ligand binding and activation of CGRP receptors. The contribution of position 7 to the conformation and topography of the disulphide bridge of h‐α‐CGRP is crucial to the future design of agonists of CGRP receptors. Furthermore, position 7 is important for the development of new CGRP receptor antagonists with structures based on the whole sequence of h‐α‐CGRP.
Contribution to the synthesis of aureobasidin A. Synthesis of cyclopeptolides containing the sequence leucyl‐N‐methyl‐β‐hydroxyvalyl‐ (2R)‐oxy‐(3R)‐methyl‐pentanoic acid *
Authors: Schmidt U. , Schumacher A. , Mittendorf J. , Riedl B. 
Published: August 2010

Abstract:The efficient antimycotic agent aureobasidin A, isolated from the culture broth of Aureobasidium pullulans R 106, and the [(R)‐Pro9]‐aureobasidin A were prepared starting from benzyl N‐Boc‐N‐methyl‐(S)‐β‐triethylsiloxyvalinate, the synthesis of which is described here. The easy accessibility of the tripeptolide benzyl Boc‐leucyl‐N‐methyl‐β‐hydroxyvalyl‐(2R)‐oxy‐(3R)‐methylpentanoate [Boc‐Leu‐HOMeVal‐(R)‐HMP‐OBn] facilitates the construction of the cyclopeptolides 28, 34, 45 and 47. The peptide bonds of the N‐methylamino acids were formed with the help of O‐(7‐azabenzotria‐zol‐1‐yl)‐1,1,3,3‐tetramethyluronium hexafluorophophate. The rings of [(R)‐Pro9]‐aureobasidin A and of cyclopeptolides 28, 34, 45 and 47 were closed by way of pentafluorophenyl esters. The ring of aureobasidin A could only be formed with bromo‐tris‐pyrrolidino‐phosphonium hexafluorophosphate.
A concise methodology for the stereoselective synthesis of O‐glycosylated amino acid building blocks: complete 1HNMR assignments and their application in solid‐phase glycopeptide synthesis
Authors: Satyanarayana J. , Gururaja T.L. , Naganagowda G.A. , Ramasubbu N. , Levine M.J. 
Published: August 2010

AbstractA facile strategy for the stereoselective synthesis of suitably protected O‐glycosylated amino acid building blocks, namely, Nα‐Fmoc‐Ser‐[Ac4‐β‐d‐Gal‐(1‐3)‐Ac2α or β‐d‐GalN3]‐OPfp and Nα‐Fmoc‐Thr‐[Ac4‐β‐d‐Gal‐(1‐3)‐Ac2‐α or β‐d‐GalN3]‐OPfp is described. What is new and novel in this report is that Koenigs‐Knorr type glycosylation of an aglycon serine/threonine derivative (i.e. Nα‐Fmoc‐Ser‐OPfp or Nα‐Fmoc‐Thr‐OPfp) with protected β‐d‐Gal(1‐3)‐d‐GalN3 synthon mediated by silver salts resulted in only α‐and/or β‐isomers in excellent yields under two different reaction conditions. The subtle differences in stereoselectivity were demonstrated clearly when glycosylation was carried out using only AgClO4 at ‐40°C which afforded α‐isomer in a quantitative yield (α:β= 5:1). On the other hand, the β‐isomer was formed exclusively when the reaction was performed in the presence of Ag2CO3AgClO4 at room temperature. A complete assignment of 1H resonances to individual sugar ring protons and the characteristic anomeric α‐1H and β‐1H in Ac4Galβ(1‐3)Ac2GalN3α and/or β linked to Ser/Thr building blocks was accomplished unequivocally by two‐dimensional double‐quantum filtered correlated spectroscopy and nuclear Overhauser enhancement and exchange spectroscopy NMR experiments. An unambiguous structural characterization and documentation of chemical shifts, including the coupling constants for all the protons of the aforementioned a‐ and p‐isomers of the O‐glycosylated amino acid building blocks carrying protected β‐d‐Gal(1‐3)‐d‐GalN3, could serve as a template in elucidating the three‐dimensional structure of glycoproteins. The synthetic utility of the building blocks and versatility of the strategy was exemplified in the construction of human salivary mucin (MUC7)‐derived, O‐linked glycopeptides with varied degrees of glycosylation by solid‐phase Fmoc chemistry. Fmoc/tert‐butyl‐based protecting groups were used for the peptidic
Crystal structure of Boc‐LAla‐ΔPhe‐ΔPhe‐ΔPhe‐ΔPhe‐NHMe: a left‐handed helical peptide
Authors: Ramagopal U. A. , Ramakumar S. , Joshi R. M. , Chauhan V. S. 
Published: August 2010

Abstractαβ‐Dehydrophenylalanine residues constrain the peptide backbone to β‐bend conformation. A pentapeptide containing four consecutive (APhe) residues has been synthesised and crystallised. The peptide Boc‐LAla‐ΔPhe‐ΔPhe‐ΔPhe‐ΔPhe‐NHMe (C45H46N6O7, MW = 782.86) was crystallised from an acetonitrile/ methanol mixture. The crystal belongs to the orthorhombic space group P212121 with a = 19.455(6), b = 20.912(9), c = 11.455(4) Å and Z = 4. The X‐ray (MoKα, lD = 0.7107 Å) intensity data were collected using the Rigaku‐AFC7 diffractrometer. The crystal structure was determined by direct methods and refined using the least‐squares technique, R = 8.41% for 1827 reflections with ‖F0‖ > 4σ‖Fo‖. The molecule contains the largest stretch of consecutive dehydrophenylalanine residues whose crystal structure has been determined so far. The peptide adopts left‐handed 310‐helical conformation despite the presence of LAla at the N‐terminus. The mean ø, Ψ values, averaged across the last four residues are 56.8° and 17.5°, respectively. There are four 41 intramolecular hydrogen bonds, characteristic of the 310‐helix. In the crystal each molecule interacts with four crystallographically symmetric molecules with one hydrogen bond each.
Conformational studies of a potent Leu11, D‐Trp12‐containing lactam‐bridged parathyroid hormone‐related protein‐derived antagonist
Authors: Maretto S. , Schievano E. , Mammi S. , Bisello A. , Nakamoto C. , Rosenblatt M. , Chorev M. , Peggion E. 
Published: August 2010

AbstractHuman parathyroid hormone‐related protein (PTHrP) is expressed in various tissues where it acts as an endocrine/paracrine factor involved in cellular growth, differentiation and development of fetal skeleton. As for parathyroid hormone (PTH), which is the hormone responsible for regulation of extracellular calcium homeostasis, the N‐terminal 1‐34 fragment can reproduce the full spectrum of calciotropic activities inherent in full‐length PTH. Truncation of six amino acid residues from the N‐terminus of both hormone sequences generates 7‐34 fragments which act as weak antagonists. Although PTH(7‐34) is a pure antagonist, PTHrP(7‐34) acts as partial agonist against the receptor shared by both hormones, the PTH/PTHrP receptor. In the current study, we analyzed the conformation of [Leu11,d‐Trp12,Lys26,Asp30]PTHrP(7‐34)NH2 (hybrid‐lactam) in a 1:1 mixture of H2O/TFE‐d3 at pH 4 by circular dichroism, nuclear magnetic resonance and distance geometry calculations. This weak antagonist (Kb= 650 nm) combines two modifications: Leu11,d‐Trp12 (Kb= 5.1 nm), reported to eliminate partial agonism and enhance potency, and Lys26‐Asp30 lactamization (Kb= 31 nm), aimed to stabilize the helical structure of the principal binding domain attributed to residues 25‐34. The helical content in 30% trifluoroethanol is 88%, i.e., higher than the corresponding linear analog, and comprises the d‐Trp12‐Thr33 segment. This hybrid lactam contains a rigid helical segment spanning the 14‐18 sequence followed by a hinge motif around Arg19‐20, but the sequence 14‐18 forms a stable helix. In all potent lactam‐containing, PTHrP‐derived agonists and antagonists studied so far, the dominant structural motif consists of two helical domains at the two ends of the sequence and of two hinge regions centered around Gly12‐Lys13 and Arg19. The weakly active agonists and antagonists do not exhibit the “hinge” around position 19. These findings suggest that the presence and location of discrete hinge regions that connect the N‐ and C‐terminal helices are essential for generating the bioactive conformation of ligands for the PTH/ PTHrP receptor.
Neues Verfahren zur Ermittlung des Weideertrages*
Authors: Kienle A. 
Published: August 2010

ZusammenfassungUm die Schwierigkeiten, die sich bei der erstgenannten Methode zur Errechnung der von Weidetieren aufgenommenen Futtermengen im Zusammenhang mit der Aufstellung einer zweiten Tiergruppe zur Ermittlung der V.‐C. ergeben, wurde noch eine andere Möglichkeit der Futtererrechnung verfolgt. Wir suchten nach einem Stoff, der quantitativ unverändert den Verdauungsapparat durchwandert, so daß also dessen Menge im Kot mit der im Futter identisch wäre und folglich nach Bestimmung dessen Anteiles am Gesamtfutter, dieses selbst leicht errechnet werden könnte. Nach Untersuchungen von Kühn, Morgen u. a. sollten im Futter und Kot gleiche Mengen an pepsin‐HCl‐unlöslichem N vorkommen, weshalb wir diesen Weg dann weiter verfolgten. Im Laufe der diesbezüglichen Versuche stellte sich nun heraus, daß die Höhe der künstlichen Verdauung weitgehend vom Feinheitsgrad der Analysensubstanz abhängig ist. In unserem Fall sind aber brauchbare Ergebnisse nur dann zu erzielen, wenn alle Werte unter genau denselben Verhältnissen erhalten werden, d. h. wenn alle Analysensubstanzen genau denselben Feinheitsgrad aufweisen. Da wir es jedoch mit frischen Substanzen zu tun hatten, die kein Mahlen zuließen und da außerdem auch beim Mahlen der getrockneten Substanzen in der üblichen Weise sich immer noch gewisse Unterschiede in der Feinheit zeigten, so blieb als der sicherste Weg der, alle Proben, die der Verdaulichkeitsbestimmung dienten, in den höchstmöglichen Feinheitsgrad zu überführen. Dies gelang durch intensives Zerreiben in der Reibschale unter Zugabe von feinem Quarzsand, wobei die erzielten Werte auch bei verschieden langer Einwirkung der Verdauungsflüssigkeit und verschiedener Konzentration derselben immer konstant blieben. Nunmehr zeigte es sich allerdings, daß die so ermittelten Mengen an pepsin‐HCl‐unlöslichem N im Kot wesentlich niedriger waren als im Futter. Diese Differenzen scheinen jedoch bei Tieren derselben Art und bei einheitlichem Futter immer gleich hoch zu sein, so daß also die Möglichkeit bestände, nach Ermittlung dieser gleichbleibenden Abweichung mit Hilfe der Quantität an unlöslichem N im Kot auch diejenige im Futter festzustellen, wonach also das gewunschte Ziel auf einem unbedeutenden Umwege doch noch zu erreichen wäre. Wir fanden bei unseren im Stall gehaltenen Ochsen, daß die Menge im Kot nur noch 74,3% von derjenigen im Futter betrug. Nachdem wir nun auch bei den Weidetieren die im Kot gefundenen Werte entsprechend umrechneten, um diejenigen im Futter zu erhalten und die Errechnung der Futtermenge hiernach vornahmen, zeigte sich tatsächlich, daß die erhaltenen Resultate mit den nach der ersten Methode erzielten gut übereinstimmen.