bluuebunny/crossref_metadata_2025 huggingface dataset:
The Rise and Fall of Modern Bounderby: An Overview of the Evolution of Economy from Mercantilism to Trumponomics with reference to Dickens’s Hard Times (1854)
Authors: Yas Khalid Ahmad
Published: February 2022

The election of Donald Trump can be examined in the context of the rise of authoritarian populist, nationalist, and anti-globalist movements throughout the world due to neoliberal policies, job outsourcing, and the influx of immigrants. Unlike preceded presidents, Trump had no previous political or military experience; instead, he popped out from the business world and entertainment culture. The paper’s endeavour is twofold: first, to trace the evolution of the economy from Mercantilism to Trumponomics, which is a mixture of mercantilism globally and neoliberal flavoured with classical crony capitalism of Dickens’ Bounderby domestically to appease his voters and not to upset his wealthy friends. The second is to draw a comparison between Donald Trump and his counterpart Josiah Bounderby, a stark example of capitalism. The paper will not only trace his ascension to the very pinnacle of world power as the president of the United States but also his fall, testing the allegations of the clown prince of American politics and whether or not he betrayed his anti-globalist followers in pursuing his and big corporates interests. Like his counterpart, Mr Bounderby, who built his image on his rags-to-riches fairy tale, Trump built his own as a man of deals. While the former left no progeny and his fortune was whittled down by the court, the latter was proved to be the worst deal-maker ever. He did more harm than good and produced nothing but a faceless economy and a nation bitterly divided.
When Individual Represents the National: Understanding Trauma through History and Myth in Anisul Hoque’s The Ballad of Ayesha
Authors: Mazumder Tanmoy
Published: February 2022

In his novel, The Ballad of Ayesha (2018), Anisul Hoque portrays a young woman named Ayesha and her sufferings in life after a sudden disappearance of her husband Joynal Abedin, an officer in Bangladesh Air Force, on a fated day in 1977. Ayesha, with her two little children, determinedly fights off the woes of life and waits, with a secret hope, for her beloved husband’s return. This tale, however, throws light on a period of extensive instability and bloodshed in the history of a newly independent Bangladesh, when a great mutiny in the armed forces has been brutally suppressed by then military ruler General Ziaur Rahman in the aftermath of his ascend to power after the brutal assasination of Bangabandhu Sheikh Mujibur Rahman in the hands of a group of military officers. The novel, as I argue, presents this history in the background of Ayesha’s traumatic experience which is parallelly presented with Behula’s trauma, a legend found in the popular folk-epic Manashamangal Kavya, in the wake of Lakhinder’s death by snake-bite on their bridal chamber due to goddess Manasha’s wrath. Thus, the text intertwines the personal trauma of an ordinary village woman with a popular myth in Bengal in the context of a dark historical chapter of Bangladesh. This paper, thus, investigates the representation of history and myth in this historical novel and argues that the narrative, while presenting individual traumas of Ayesha and Behula, ultimately foregrounds a period of national trauma in the history of Bangladesh, and challenges some propagandist political narratives at the same time.
From hair to liver: emerging application of hair follicle mesenchymal stem cell transplantation reverses liver cirrhosis by blocking the TGF-β/Smad signaling pathway to inhibit pathological HSC activation
Authors: Liu Qi , Lv Chengqian , Jiang Yanan , Luo Kunpeng , Gao Yang , Liu Jingyang , Zhang Xu , Mohammad Omar Jan , Jin Shizhu
Published: February 2022

Liver cirrhosis (LC) involves multiple systems throughout the body, and patients with LC often die of multiple organ failure. However, few drugs are useful to treat LC. Hair follicle mesenchymal stem cells (HF-MSCs) are derived from the dermal papilla and the bulge area of hair follicles and are pluripotent stem cells in the mesoderm with broad prospects in regenerative medicine. As an emerging seed cell type widely used in skin wound healing and plastic surgery, HF-MSCs show considerable prospects in the treatment of LC due to their proliferation and multidirectional differentiation capabilities. We established an LC model in C57BL/6J mice by administering carbon tetrachloride (CCl4) and injected HF-MSCs through the tail vein to explore the therapeutic effects and potential mechanisms of HF-MSCs on LC. Here, we found that HF-MSCs improved liver function and ameliorated the liver pathology of LC. Notably, PKH67-labeled HF-MSCs were detected in the injured liver and expressed the hepatocyte-specific markers cytokeratin 18 (CK18) and albumin (ALB). In addition, in contrast to that in the LC group, the α-SMA expression showed a decreasing trend in the treatment group in vitro and in vivo, indicating that the pathological activation of hepatic stellate cells (HSCs) was inhibited by HF-MSC treatment. Moreover, the levels of transforming growth factor β (TGF-β1) and p-Smad3, a signaling molecule downstream of TGF-β1, were increased in mice with LC, while HF-MSC treatment reversed these changes in vivo and in vitro. Based on these findings, HF-MSCs may reverse LC by blocking the TGF-β/Smad pathway and inhibiting the pathological activation of HSCs, which may provide evidence for the application of HF-MSCs to treat LC.
Computed Tomography and Magnetic Resonance Imaging of Preoperative Cases of Esthesioneuroblastoma (Olfactory Neuroblastoma): A Case Series
Authors: Lohey Mohit Rameshrao , Patil Satish D , Patil Shivanand V , Ravikumar . , Nimbal Vishal S , Kanamadi Suresh
Published: February 2022

Esthesioneuroblastoma is an uncommon aggressive tumour arising from the olfactory epithelium of superior nasal cavity, frequently invading the base of cranium, cranial vault and orbit. Contrast enhanced Computed Tomography (CT) and contrast enhanced Magnetic Resonance Imaging (MRI) were done for three patients which showed modified Kadish stage C tumour. Biopsy was done to confirm the diagnosis and patients were subjected to surgery and radiotherapy. The purpose of this case series was to report the radiological features of esthesioneuroblastoma. This is a report on three cases of different age groups who presented tumour with intracranial extension which were histopathologically proven as esthesioneuroblastoma.
Excavation of an Iron Age burial mound, Loch Borralie, Durness, Sutherland
Authors: MacGregor Gavin , Roberts Julie , Cox Adrian , Donnelly Michael , Evans Caitlin , Arthur John
Published: February 2022

As part of the Historic Scotland Human Remains Call Off Contract, Glasgow University Archaeological Research Division (GUARD) undertook an archaeological evaluation of the find spot of a human skull from a cairn at Loch Borralie, Sutherland (NGR: NC 3790 6761). Excavation recovered the remains of two burials beneath the cairn and established that the cairn was multi-phased. One individual was an adult male (Skeleton 1), while the other was immature and of undeterminable sex (Skeleton 2). Both individuals showed signs of ill health, and dogs and/or rats appear to have gnawed their bones. A ring-headed pin was recovered close to Skeleton 1 during the excavation. A radiocarbon date was obtained from the left humerus of Skeleton 1 of 40 cal BC - cal AD210 at 2 sigma (OxA-10253). Excavation revealed that the cairn, broadly sub-rectangular in form, had a maximum height of 1.2m and was composed of large, sub-angular and sub-rounded rocks (including quartz and quartzite) and occasional rounded cobbles within yellow-orange sand. One inhumation, Skeleton 2, lay within an irregular grave, cut through the red brown sand that was sealed by the cairn and into the natural gravel sand below. The other inhumation, Skeleton 1, was sealed by the red brown sand and had been placed on a low primary cairn of stone and earth, the full extent and depth of which remains unknown. The tradition of extended inhumations within sub-rectangular cairns is a recognised funerary practice in the north of Britain during the first millennium AD. Many of these burials are generally considered to be Pictish in date, but Loch Borralie indicates that the tradition commenced in the Iron Age. There is increasing evidence for the variety of ways in which human remains were treated after death in the Iron Age, including cremations in re-used cists, single inhumations in graves and cists, multiple inhumations and the incorporation of human remains in 'domestic' contexts. The results of the excavation of the burial mound at Loch Borralie provide a useful addition to the range of mortuary and funerary rites which were practised during the Iron Age in Scotland.
Molecular characterization and cell cycle‐regulated expression of a cDNA clone from Arabidopsis thaliana homologous to the small subunit of ribonucleotide reductase
Authors: Philipps Gabriel , Clement Bernadette , Gigot Claude
Published: July 2002

A cDNA clone isolated from an Arabidopsis thaliana cell suspension library showed highly significant homology to the small subunit of ribonucleotide reductase (R2) from different species. The 340 amino acid‐long deduced putative protein contains all the residues that are important for the enzyme activity and structure. In A. thaliana this enzyme is encoded by a single‐copy gene. In synchronized tobacco BY2 cells the corresponding mRNAs specifically accumulate during the S phase of the cell cycle.
Activation of bee venom phospholipase A2 through a peptide‐enzyme complex
Authors: Mingarro Ismael , Pérez-Payá Enrique , Pinilla Clemencia , Appel Jon R. , Houghten Richard A. , Blondelle Sylvie E.
Published: July 2002

Phospholipase A2 activation by membrane‐bound peptides was investigated in order to understand the role of the membrane‐induced conformation on activation, and to examine the occurrence of a peptide‐enzyme complex at the lipid/water interface. For the peptides studies, bee venom phospholipase A2 was stimulated regardless of the membrane‐bound conformation (α‐helix, β‐sheet or random coil). Using antisera raised against melittin, we were able to demonstrate the occurrence of a calcium‐dependent complex involving the enzyme, phospholipid substrate, and peptide.
RNA editing in wheat mitochondria proceeds by a deamination mechanism
Authors: Blanc Valérie , Litvak Simón , Araya Alejandro
Published: July 2002

Most if not all mitochondrial messenger RNAs from seed plants undergo a post‐transcriptional modification (RNA editing) involving the conversion of some cytidine residues to uridine. Using a molecular hybridization approach, an in vitro RNA editing system, able to faithfully reproduce the in vivo observed C to U changes of subunit 9 (atp9) of wheat mitochondrial ATP synthase mRNA, has been described [Araya et al. (1992) Proc. Natl. Acad. Sci. USA 89, 1040–1044]. In this work we extend these studies to better understand the biochemical mechanism of this process. RNA editing was analysed by P1 nuclease digestion of the reaction product followed by thin layer chromatography. Experiments performed with unedited [3H]RNA labelled on the base and with unedited [32P]RNA labelled at the α‐phosphate of cytidine residues, indicate that plant mitochondrial RNA editing operates through a deamination mechanism.
Binding of vanadium (IV) to the phosphatase calcineurin
Authors: Parra-Diaz Dennisse , Wei Qun , Lee Ernest Y.C. , Echegoyen Luis , Puett David
Published: July 2002

X‐band electron spin resonance spectroscopy was used to study the binding of vanadium (IV), or vanadyl, to the brain serine/threonine phosphatase‐2B, calcineurin. Spectra were determined on frozen solutions of vanadyl and calcineurin at pH 7.4 in the presence of 20% (v/v) glycerol. The binding of vanadyl to the enzyme was established, and the data suggested the presence of two classes of sites, the higher affinity class of which contained two binding sites for vanadyl. The calcium‐binding B subunit of the heterodimeric protein was also shown to bind vanadyl. The holoprotein appeared to be stabilized by vanadyl, and vanadyl enhanced enzymatic activity when assayed with or without calmodulin in the absence of calcium.
Masthead V.3 No.1
Authors: Mandell Lewis
Published: July 2002

NA
From the Editor Vol 3 No 1
Authors: Mandell Lewis
Published: July 2002

NA
Efficient Frontiers in Estate Planning
Authors: Crabb Ronald R.
Published: July 2002

This article explores the nature of the efficientfrontier in probabilistic estate planning for 16 different estate pkms by considering as random variables ages at deatk rates of return on assets, and borrowing rates on debts. The simulation considers two couples, one middle aged, the other elderly. Two 16x16 matrices, one for each couple, are used to record and compare the results of every simulation. That comparative data, in conjunction with the coefficient of variation based efficient frontier, contain usefull information for couples who, consistent with their levels of risk, desire to maximize the net present value of assets pass to their heirs.The efficient frontier is shown to be a function of three fators: assumptions, ages of the estate owners, and the discount rates of the heirs. Because of the instability shown in the eficient frontier, estate planners and estate owners must carefully examine not only the estate plans whichfall on the efficient frontier but also those estate plans which fall just off that frontier.
Analysis of the fine specificity of Tn‐binding proteins using synthetic glycopeptide epitopes and a biosensor based on surface plasmon resonance spectroscopy
Authors: Osinaga Eduardo , Bay Sylvie , Tello Diana , Babino Alvaro , Pritsch Otto , Assemat Karine , Cantacuzene Daniele , Nakada Hiroshi , Alzari Pedro
Published: July 2002

Using synthetic Tn (GalNAc‐O‐Ser/Thr) glycopeptide models and a biosensor based on surface plasmon resonance spectroscopy we have determined that isolectin B4 from Vicia villosa (VVLB4) binds to one Tn determinant whereas the anti‐Tn monoclonal antibodies 83D4 and MLS128 require at least two Tn residues for recognition. When an unglycosylated amino acid is introduced between the Tn residues, both antibodies do not bind. MLS128 affinity was higher on a glycopeptide with three consecutive Tn residues. These results indicate that Tn residues organized in clusters are essential for the binding of these antibodies and indicate a different Tn recognition pattern for VVLB4.
IgA1 protease from Neisseria gonorrhoeae inhibits TNFα‐mediated apoptosis of human monocytic cells
Authors: Beck Susanne C. , Meyer Thomas F.
Published: July 2002

The modulation of programmed cell death is a common theme in the patho‐physiology of inflammation and infectious disease. The synthesis and secretion of an IgA1 protease is strictly associated with virulence of the Neisseria species. Here, we report on the inhibition of tumor necrosis factor α (TNFα)‐mediated apoptosis of the human myelo‐monocytic cell line U937 by highly purified IgA1 protease. Apoptosis was verified by the cell surface exposure of phosphatidyl serine and by terminal transferase mediated end‐labeling of fragmented DNA. Interestingly, IgA1 protease specifically cleaved the TNF receptor II (TNF‐RII) on the surface of intact cells whereas TNF‐RI was not affected by the enzyme. Therefore, inhibition of TNFα‐mediated apoptosis might be correlated to specific cleavage of the TNF‐RII by neisserial IgA1 protease.
Flavonoids can replace α‐tocopherol as an antioxidant
Authors: van Acker Frédérique A.A. , Schouten Olga , Haenen Guido R.M.M. , van der Vijgh Wim J.F. , Bast Aalt
Published: July 2002

Endogenous antioxidants such as the lipid‐soluble vitamin E protect the cell membranes from oxidative damage. Glutathione seems to be able to regenerate α‐tocopherol via a so‐called free radical reductase. The transient protection by reduced glutathione (GSH) against lipid peroxidation in control liver microsomes is not observed in microsomes deficient in α‐tocopherol. Introduction of antioxidant flavonoids, such as 7‐monohydroxyethylrutoside, fisetin or naringenin, into the deficient microsomes restored the GSH‐dependent protection, suggesting that flavonoids can take over the role of α‐tocopherol as a chain‐breaking antioxidant in liver microsomal membranes.
Learning by doing
Authors: Eyssell Thomas H.
Published: July 2002

Given the importance of interpersonal relationships in the financial planning process, it is surprising that relatively few registered financial planning programs explicitly provide students the opportunity to meet with real clients on a one-to-one basis. This paper describes the structure of a financial planning practicum developed for the purpose of providing such experience to future financial planners. It is hoped that this information will encourage others to consider offering experiential learning opportunities to those seeking positions in the financial services industry. © 1999 Elsevier Science Inc. All rights reserved.
Ventilatory capacity and exercise tolerance in patients with chronic stable heart failure
Authors: Clark Andrew L. , Davies L. Ceri , Francis Darrel P. , Coats Andrew J.S.
Published: July 2002

Background

Patients with chronic heart failure complain of breathlessness. This is associated with an increase in the ventilatory response to carbon dioxide production (Ve/Vco2 slope), yet a reduction in the maximal ventilation achieved at peak exercise. We analysed ventilatory capacity in heart failure in relation to exercise capacity.

Methods

We analysed data from 74 patients with chronic stable heart failure [age (S.D.) 50.6 (8.8) years; left ventricular ejection fraction 30 (15)%] and 36 controls [48.9 (11.5) years]. Subjects undertook maximal incremental exercise testing with metabolic gas exchange measurements to derive peak oxygen consumption (Vo2), the Ve/Vco2 slope and ventilation. Spirometry was used to measure FEV1 and FVC. Maximal voluntary ventilation (MVV) was calculated as FEV1×35.

Results

Peak Vo2 was lower in patients [20.9 (7.5) ml min−1 kg−1 vs. 34.5 (10.1); P<0.001] and Ve/Vco2 greater [33.4 (10.7) vs. 26.0 (4.7); P<0.001]. Ventilation at peak exercise was lower in patients [63.5 (20.4) l/min vs. 86.9 (29.5); P<0.001], as was MVV [110.1 (37.9) l/min vs. 136.2 (53.1); P<0.001], but ventilation at peak as a proportion of MVV was the same in patients [60.0 (19.0)%] as controls [65.7 (12.4)%)]. There was an inverse relation between peak Vo2 and Ve/Vco2 slope (r=−0.62; P<0.001). Percentage predicted FEV1 correlated with ventilation at peak (r=0.62; P<0.001) and inversely with Ve/Vco2 slope (r=−0.32; P<0.001). There was no relation between percentage of MVV achieved and peak Vo2, or Ve/Vco2 slope.

Conclusions

Although ventilation at peak exercise is lower in patients with heart failure than normal subjects, ventilation is the same proportion of maximal voluntary ventilation. These findings suggest that ventilatory capacity does not limit exercise capacity in heart failure.
Management of heart failure in Switzerland
Authors: Muntwyler Jörg , Follath Ferenc
Published: July 2002

Similar to other countries, heart failure is a major cause of morbidity and mortality in Switzerland. Among heart failure patients admitted to a Swiss university hospital in 1998, admission therapy included: ACE inhibitors/AT‐II blockers in approximately two‐thirds; diuretics in approximately 70%; and beta‐blockers in approximately one‐third. Easy access to diagnostic tests and limited results of surveys suggest that quality of care of heart failure patients is satisfactory in Switzerland. However, results from ongoing studies are required to assess more reliably the quality of diagnosis and therapy of this high‐risk population in Switzerland.
Direct Measurement of pH Profiles in Immobilized Enzyme Carriers during Kinetically Controlled Synthesis Using CLSM
Authors: Spiess Antje C. , Kasche Volker
Published: July 2002

Confocal laser scanning microscopy was applied to measure the pH value in the carrier of immobilized enzymes during the enzyme‐catalyzed synthesis. pH profiles with a high resolution are shown, with the pH increasing in the core of the particles. Significant differences occur for different carrier material, particle size, porosity and surface modification. The increased pH value is identified as one of the reasons leading to reduced enzyme selectivity in the penicillin amidase catalyzed synthesis of cephalosporins and penicillins.
Control and Fault Diagnosis in Bottom Fermentation Systems Using Parity Space Approach
Authors: Riverol C. , Pilipovik M. V.
Published: July 2002

The main objective of this note is to describe a real‐time fault diagnosis and control for a cylindroconical fermenter to laboratory scale as an alternative to the classic systems. Development of a good controller for a fed‐batch reactor is not enough without a fault diagnosis system. We are working to expand this idea. The failure detection system is based on the parity space approach joined with a fuzzy controller with more robustness and of superior performance in MIMO systems compared to conventional strategies. A 2‐week period is reported.
Effect of Oxygen Limitation on β‐Lactamase Production
Authors: Sargantanis Ioannis G. , Karim M. N.
Published: July 2002

The dissolved oxygen concentration (DO) is an important variable in aerobic fermentations. Precise control of the DO is critical in fermentation processes for the investigation of the best conditions for secondary product formation. Oxygen limitation conditions have been known to enhance the synthesis of secondary products. An adaptive pole placement control that maintains a constant sheer environment is applied to Bacillus subtilis fermentation for the production of β‐lactamase. Auto Regressive eXogeneous (ARX) input models are used for the control, and supervision and coordination techniques are applied to improve the control performance. The effect of DO level on the productivity of β‐lactamase under oxygen‐limited conditions is assessed.
Parameters Affecting the Efficiency of Affinity‐Based Reversed Micellar Extraction and Separation (ARMES) in Glycoprotein Purification
Authors: Choe Jaehoon , VanderNoot Victoria A. , Linhardt Robert J. , Dordick Jonathan S.
Published: July 2002

Affinity‐based reversed micellar extraction and separation (ARMES) is an effective method for purifying both low and high molecular weight glycoproteins via liquid‐liquid extraction. A range of extraction conditions were examined to gain insight into the mechanism of ARMES. Concanavalin A (Con A) was used as the model affinity ligand to bind soybean peroxidase (SBP) and β‐galactosidase as model glycoproteins. Factorial design was used to investigate the effect of various system variables on the extraction of SBP via ARMES. A quadratic model described the system well, resulting in a standard deviation of 7% between calculated and experimental extraction efficiencies. Sensitivity analysis suggested that the key criteria in ARMES were the NaCl concentration and pH of the aqueous feed phase. Extraction of both glycoproteins decreased above pH 7 but fell to zero only at pH values significantly above the pI of the model glycoproteins and the Con A affinity ligand. It is proposed that the complex of the affinity lectin with the glycoprotein results in a sufficiently hydrophobic species that can be extracted into a reversed micellar organic phase even at pH's far above the pI's of the individual proteins that comprise the complex. This finding has practical considerations for the use of ARMES in the resolution and purification of protein glycoforms.
Reactor Design Issues for Synthesis‐Gas Fermentations
Authors: Bredwell Marshall D. , Srivastava Prashant , Worden R. Mark
Published: July 2002

Synthesis gas is readily obtained by gasifying coal, oil, biomass, or waste organics and represents an abundant, potentially inexpensive, feedstock for bioprocessing. The primary components of synthesis gas, carbon monoxide and hydrogen, can be converted into methane, organic acids, and alcohols via anaerobic fermentations. Bioconversion of synthesis gas is an attractive alternative to catalytic processing because the biological catalysts are highly specific and often more tolerant of sulfur contaminants than inorganic catalysts. However, because the aqueous solubilities of carbon monoxide and hydrogen are low, synthesis‐gas fermentations are typically limited by the rate of gas‐to‐liquid mass transfer. Consequently, a major engineering challenge in commercial development of synthesis‐gas fermentations is to provide sufficient gas mass transfer in an energy‐efficient manner. This paper reviews recent progress in the development of synthesis‐gas fermentations, with emphasis on efforts to increase the efficiency of gas mass transfer. Metabolic properties of several microbes able to ferment synthesis gas are described. Results of synthesis‐gas fermentations conducted in various bioreactor configurations are summarized. Recent results showing enhancement of synthesis‐gas fermentations using microbubble dispersions are presented, and studies of the mass‐transfer and coalescence properties of microbubbles are described.
Conformational properties of a cyclic peptide bradykinin B2 receptor antagonist using experimental and theoretical methods
Authors: Krause K. , Pineda L.F. , Peteranderl R. , Reissmann S.
Published: July 2002

Abstract: The solution conformation of the cyclic peptide J324 (cyclo0,6‐[Lys0,Glu6,d‐Phe7]BK), an antagonist targeted at the bradykinin (BK) B2 receptor, has been investigated using experimental and theoretical methods. In order to gain insight into the structural requirements essential for BK antagonism, we carried out molecular dynamics (MD) simulations using simulated annealing as the sampling protocol. Following a free MD simulation we performed simulations using nuclear Overhauser enhancement (NOE) distance constraints determined by NMR experiments. The low‐energy structures obtained were compared with each other, grouped into families and analyzed with respect to the presence of secondary structural elements in their backbone. We also introduced new ways of plotting structural data for a more comprehensive analysis of large conformational sets. Finally, the relationship between characteristic backbone conformations and the spatial arrangement of specific pharmacophore centers was investigated.
1H‐NMR determination of the solution structure and absolute configuration of FR134043, a novel inhibitor of human leukocyte elastase
Authors: Nakanishi I. , Fujikawa A. , Imai K. , Sato A.
Published: July 2002

Abstract: FR134043 is a semisynthetic disulfonated derivative of the natural product FR901277, is isolated from the culture filtrate of Streptomyces resistomicificus and has potent inhibitory activity against human leukocyte elastase. Although the chemical structure of FR134043 was determined to be a unique bicyclic peptide‐like compound consisting of seven amino acids by using several spectroscopic analytical methods, the chiralities of three centers were unknown. A simple simulated annealing protocol to determine the structure was applied to the eight possible stereoisomers, and the one that best satisfied the NOE distance constraints was determined to be the true stereoconfiguration of FR134043. The solution structure showed that all Cα atoms existed in the l configuration and six of the seven side chains were located towards the outside of the bicyclic framework, even though most of them are highly hydrophobic moieties. The simulated annealing calculation described here is a frequently used method for the determination of the solution structure of peptides or small proteins. We show here that it is also applicable to the determination of the absolute configuration of macrocyclic compounds produced from natural sources.
Highly fluorescent protein labeling using dendritic peptide derivatives
Authors: Giovannoni L. , Lozzi L. , Neri D. , Neri P.
Published: July 2002

Abstract: Non‐specific fluorescent dyes and photosensitizers are routinely used in clinical practice for the photodetection and photoablation of superficial lesions. Future applications in photomedicine are likely to rely on the selective delivery of photoactive compounds to diseased areas, using specific targeting agents such as antibodies. This fact underlines the need for methods that allow the chemically defined conjugation of several photoactive molecules to a single protein ‘vehicle’, with full retention of binding affinity. Here, we present methods for the site‐specific fluorescent labeling of proteins using dendritic peptides, which had been chemically modified with multiple molecules of fluorescein. Branched peptide derivatives can be stably conjugated to proteins either by reaction with suitable free reactive groups or by using the high‐affinity non‐covalent interaction between calmodulin and a specific binding peptide. Chemical modification of proteins with one, two or four molecules of fluorescein resulted in a proportional increase in protein fluorescence.
Structures of the intradiskal loops and amino terminus of the G‐protein receptor, rhodopsin
Authors: Yeagle P.L. , Albert A.D. , Salloum A. , Chopra A. , Bhawsar N. , Ali L. , Kuzmanovski G. , Alderfer J.L.
Published: July 2002

Abstract: The intradiskal surface of the transmembrane protein, rhodopsin, consists of the amino terminal domain and three loops connecting six of the seven transmembrane helices. This surface corresponds to the extracellular surface of otherG‐protein receptors. Peptides that represent each of the extramembraneous domains on this surface (three loops and the amino terminus) were synthesized. These peptides also included residues which, based on a hydrophobic plot, could be expected to be part of the transmembrane helix. The structure of each of these peptides in solution was then determined using two‐dimensional 1H nuclear magnetic resonance. All peptide domains showed ordered structures in solution. The structures of each of the peptides from intradiskal loops of rhodopsin exhibited a turn in the central region of the peptide. The ends of the peptides show an unwinding of the transmembrane helices to form this turn. The amino terminal domain peptide exhibitedα‐helical regions with breaks and bends at proline residues. This region forms a compact domain. Together, the structures for the loop and amino terminus domains indicate that the intradiskal surface of rhodopsin is ordered. These data further suggest a structural motif for short loops in transmembrane proteins. The ordered structures of these loops, in the absence of the transmembrane helices, indicate that the primary sequences of these loops are sufficient to code for the turn.
Stereoselective deuterium labeling of proRβ‐protons in the NMR structure determination of a helix‐turn‐helix turn peptide mimic
Authors: Etzkorn F.A. , Travins J.M.
Published: July 2002

Abstract: The NMR structure of a small, side‐chain‐cyclized tripeptide mimic of the turn in the helix‐turn‐helix (HTH) motif was determined. The four β‐protons were stereospecifically assigned by stereoselective deuterium replacement of only the proRβ‐protons. All 24 of 30 NOESY cross‐peaks not involving chemically defined or freely rotating protons, and six of seven coupling constants from the P.COSY were used as distance and angle constraints in molecular modeling. MacroModel found 33/1000 structures in the NMR constrained search and 263/1000 structures in the unconstrained search, indicating meaningful constraint by the NMR data. However, the 10 lowest‐energy structures from the unconstrained and constrained searches are very similar, so modeling alone was able to find the experimentally determined structure.
Synthesis of different types of dipeptide building units containing N‐ or C‐terminal arginine for the assembly of backbone cyclic peptides*
Authors: Schumann C. , Seyfarth L. , Greiner G. , Reissmann S.
Published: July 2002

Abstract: Different types of dipeptide building units containing N‐ or C‐terminal arginine were prepared for synthesis of the backbone cyclic analogues of the peptide hormone bradykinin (BK: Arg‐Pro‐Pro‐Gly‐Phe‐Ser‐Pro‐Phe‐Arg). For cyclization in the N‐terminal sequence N‐carboxyalkyl and N‐aminoalkyl functionalized dipeptide building units were synthesized. In order to avoid lactam formation during the condensation of the N‐terminal arginine to the N‐alkylated amino acids at position 2, the guanidino function has to be deprotected. The best results were obtained by coupling Z‐Arg(Z)2‐OH with TFFH/collidine in DCM. Another dipeptide building unit with an acylated reduced peptide bond containing C‐terminal arginine was prepared to synthesize BK‐analogues with backbone cyclization in theC‐terminus. To achieve complete condensation to the resin and to avoid side reactions during activation of the arginine residue, this dipeptide unit was formed on a hydroxycrotonic acid linker. HYCRAM™ technology was applied using the Boc‐Arg(Alloc)2‐OH derivative and the Fmoc group to protect the aminoalkyl function. The reduced peptide bond was prepared by reductive alkylation of the arginine derivative with the Boc‐protected amino aldehyde, derived from Boc‐Phe‐OH. The best results for condensation of the branching chain to the reduced peptide bond were obtained using mixed anhydrides. Both types of dipeptide building units can be used in solid‐phase synthesis in the same manner as amino acid derivatives.
Isolation and characterization of insulin from the Brockmann body of Dissostichus mawsoni, an Antarctic teleost fish
Authors: Bachle L.A. , Smith D.D. , Petzel D.
Published: July 2002

Abstract: The Brockmann body of fish synthesizes and secretes insulin. The Brockmann body of Antarctic fish has been described anatomically and shown to contain insulin immunoreactive sites, however, the primary structure of an Antarctic fish insulin has yet to be reported. Insulin was isolated from the Brockmann bodies of the Antarctic perciform teleost, Dissostichus mawsoni. The peptide was purified to homogeneity by gel filtration and reversed‐phase HPLC. Insulin‐containing fractions were identified by radioimmunoassay using antisera raised against porcine insulin. Electrospray ionization‐mass spectrometry determined the mass of the isolated product to be 5725.27 a.m.u. The amino acid composition and primary structure were determined for the pyridylethylated A‐ and B‐ chains. The amino acid sequences of the A chain and B chain were H‐Gly‐Ile‐Val‐Glu‐Gln‐Cys‐Cys‐His‐Gln‐Pro10‐Cys‐Asn‐Ile‐Phe‐Asp‐Leu‐Gln‐Asn‐Tyr‐Cys20‐Asn‐OH and H‐Ala‐Pro‐Gly‐Pro‐Gln‐His‐Leu‐Cys‐Gly‐Ser10‐His‐Leu‐Val‐Asp‐Ala‐Leu‐Tyr‐Leu‐Val‐Cys20‐Gly‐Glu‐Arg‐Gly‐Phe‐Phe‐Tyr‐Asn‐Pro‐Lys30‐OH, respectively. The primary structure of insulin from Antarctic fish is compared with known structures of insulin from other vertebrates.
Structural study of the sodium channel inactivation gate peptide including an isoleucine–phenylalanine–methionine motif and its analogous peptide (phenylalanine/glutamine) in trifluoroethanol solutions and SDS micelles
Authors: Kuroda Y. , Miyamoto K. , Matsumoto M. , Maeda Y. , Otaka A. , Fujii N. , Nakagawa T. , Kanaori K.
Published: July 2002

In order to gain insight into the gating mechanisms of Na+ channels, in particular their inactivation mechanisms, we studied the structures of the Na+ channel inactivation gate related peptide which includes the IFM (Ile‐Phe‐Met) motif (Ac‐KKKFGGQDIFMTEEQKK‐NH2; K1480–K1496 in rat brain type‐IIA Na+ channels, MP‐3A) and its F/Q(Gln) substituted one (MP‐4A) in trifluoroethanol (TFE) solutions and sodium dodecyl sulfate (SDS) micelles using circular dichroism (CD) and 1H‐NMR spectroscopies. Based on observed nuclear Overhauser effect constraints, three‐dimensional structures of MP‐3A and MP‐4A were determined using simulated annealing molecular dynamics/energy minimization calculations. In TFE solutions, no appreciable differences in the structure were observed using either CD or NMR spectra. In SDS micelles, however, the two peptides exhibited definitely different structures from each other. It was found that in MP‐3A, residues I1488 and T1491 were spatially proximate with each other owing to hydrogen bonding between the amide proton of I1488 and the hydroxyl oxygen atom of T1491, whereas in MP‐4A, F/Q substitution separated them owing to conformational changes. The solvent‐accessible surfaces calculated for the structures of MP‐3A and MP‐4A showed that the former has a smoother interaction surface to the hydrophobic docking site than the latter. In conclusion, the conformational changes, as well as decreased hydrophobicity around the IFM motif owing to the F/Q mutation, may be one reason why F1489Q mutated channels cannot inactivate almost completely.
Does down‐regulation of photosynthetic capacity by elevated CO2 depend on N supply in Dactylis glomerata?
Authors: Harmens Harry , Stirling Clare M. , Marshall Chris , Farrar John F.
Published: July 2002

Dactylis glomerata was grown hydroponically in a controlled environment at ambient (360 μl l−1) or elevated (680 μl l−1) CO2 and four concentrations of nitrogen (0.15, 0.6, 1.5 and 6.0 mM NO3−), to test the hypothesis that reduction of photosynthetic capacity at elevated [CO2] is dependent on N availability and mediated by a build‐up of non‐structural carbohydrates. Photosynthetic capacity of the youngest fully expanded leaf (leaf 5, 2 days after full expansion) was reduced in CO2‐enriched plants at low, but not high N supply and so the stimulation of net photosynthesis by CO2 enhancement was less at low than at high N supply. CO2 enrichment resulted in a decrease in ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco) content on a leaf area basis at 0.6 and 1.5 mM NO3−, but not at 0.15 and 6.0 mM NO3−, and had no effect on the total N content of the leaf on an area basis. However, decreases in Rubisco content could be primarily accounted for by a decrease in total N content of leaves, independent of [CO2]. A doubling of the Rubisco content by increasing the N supply beyond 0.6 mM had only a marginal effect on the maximum carboxylation velocity in vivo, suggesting that the fraction of inactive Rubisco increased with increasing N supply. Although CO2‐enriched plants accumulated more non‐structural carbohydrates in the leaf, the reduction of photosynthetic capacity at low N supply was not mediated simply by a build‐up of carbohydrates. In D. glomerata, the photosynthetic capacity was mainly determined by the total N content of the leaf.
Cytosolic and chloroplastic glutamine synthetase of sugarbeet (Beta vulgaris) respond differently to organ ontogeny and nitrogen source
Authors: Brechlin Peter , Unterhalt Andrea , Tischner Rudolf , Mäck Gisela
Published: July 2002

Changes in the activity and subunit composition of cytosolic glutamine synthetase (GS 1; EC 6.3.1.2) and chloroplastic GS (GS 2) were studied in response to an internal (organ ontogeny) and external signal (N source: NO3− or NH4+). Maximum GS 1 activity of all organs examined was measured in the fibre roots, irrespective of the N source. The response of GS 1 to the N source was, however, organ specific. In the fibre roots, NH4+ nutrition resulted in a 2‐ to 7‐fold (based on protein or freshweight, respectively) increase of GS 1 activity compared to NO3−‐grown plants. In contrast to the roots, GS 1 activity in the leaf blades was 2‐fold lower with NH4+ nutrition, whereas only minor changes occurred in the petioles. GS 2 activity was highest in the mature and senescing leaf blade; activity was 2‐fold higher with NH4+ than with NO3− nutrition. Not only activity, but also subunit composition of GS 1 changed during organ ontogeny as well as in response to the N source. In contrast to GS 1, only minor changes were evident in GS 2 subunit composition, despite significant changes in GS 2 activity. Up to 5 different GS 1 subunits of ≈41–43 kDa were separated; they were identical in all organs examined. GS 2 was composed of 4 different subunits of ≈48 kDa.
A new dentist for a new century
Authors: Scott John
Published: July 2002

The beginning of a new year, a new century and a new millennium, is an opportunity to pause for thought. It provides perspective and a reason to examine again the continuing evolution of dentistry as a profession, and dental education in support of that development. It is an optimal time to re‐focus on our role as educators and custodians of the quality of future dental care, as today's students transform into tomorrow's practitioners, responsible over the coming decades for the oral health of a European population exceeding 375 million in the EU alone. Thus, we are aware of formidable responsibilities, and in this age of audit, and accountability for systems and services, it is entirely fitting that the recent scientific meeting of ADEE held in Milan under the Presidency of Professor Antonio Carrassi, took the above title as its theme to augur in the new decade. The Conference Proceedings are published in this issue of the Journal. They provide an exciting overview and indication of the changes ahead and the challenges to dental education.
Inhibition of potato lipoxygenase by linoleyl hydroxamic acid: kinetic and EPR spectral evidence for a two-step reaction
Authors: BUTOVICH Igor A. , REDDY C. Channa
Published: July 2002

The reaction mechanism of an electrophoretically pure potato tuber lipoxygenase (ptLOX) was studied by EPR spectroscopy. An EPR spectrum of the ‘native’ ptLOX recorded at 4.5±0.5K showed signals of a high-spin (pseudo) axial Fe3+ with a g-value of approx. 6.3±0.1 with a shoulder at g = 5.9±0.1, and a rhombic Fe3+ signal at g = 4.35±0.05. When the enzyme was treated with a 2-fold molar excess of 13(S)-hydroperoxyoctadecadienoic acid [13(S)-HPODE], a 3-fold increase in the integral intensity of the g = 6.3 signal was observed, indicating that 25% of the native ptLOX iron was in ferrous state. The positional isomer 9(S)-HPODE caused similar spectral changes. Therefore the catalytic centre of ptLOX appears to accommodate both positional isomers of linoleic acid hydroperoxides in a manner that ensures proper alignment of their hydroperoxy groups with the iron centre of the enzyme. Treatment of the Fe3+-ptLOX form with a 3-fold molar excess of linoleyl hydroxamic acid (LHA) completely quenched the g = 6.3 signal. Concurrently, a dramatic increase in the signal at g = 4.35 was detected, which was attributed to a newly formed LHA—Fe3+-ptLOX complex. The spectral characteristics of the complex are similar to those of a 4-nitrocatechol—Fe3+-ptLOX complex. From these observations, we conclude that LHA did not reduce Fe3+ to Fe2+, but rather formed a LHA—Fe3+-ptLOX complex. Formation of such a complex may be responsible for the inhibitory activity of LHA, at least in the initial stages of enzyme inhibition. A prolonged 15min incubation of the complex at 23±1°C led to the partial quenching of the g = 4.35 signal. The quenching is attributed to the reduction of Fe3+-ptLOX by LHA, with concomitant formation of its oxidation product(s). A kinetic scheme for the inhibition is proposed.
Absence of the psbH gene product destabilizes photosystem II complex and bicarbonate binding on its acceptor side in Synechocystis PCC 6803
Authors: Komenda Josef , Lupínková Lenka , Kopecký Jiří
Published: July 2002

The PsbH protein, a small subunit of the photosystem II complex (PSII), was identified as a 6‐kDa protein band in the PSII core and subcore (CP47–D1–D2–cyt b‐559) from the wild‐type strain of the cyanobacterium Synechocystis PCC 6803. The protein was missing in the D1–D2–cytochrome b‐559 complex and also in all PSII complexes isolated from IC7, a mutant lacking the psbH gene. The following properties of PSII in the mutant contrasted with those in wild‐type: (a) CP47 was released during nondenaturing electrophoresis of the PSII core isolated from IC7; (b) depletion of CO2 resulted in a reversible decrease of the␣ reoxidation rate in the IC7 cells; (c) light‐induced decrease in PSII activity, measured as 2,5–dimethyl‐benzoquinone‐supported Hill reaction, was strongly dependent on the HCO3– concentration in the IC7 cells; and (d) illumination of the IC7 cells lead to an extensive oxidation, fragmentation and cross‐linking of the D1 protein. We did not find any evidence for phosphorylation of the PsbH protein in the wild‐type strain. The results showed that in the PSII complex of Synechocystis attachment of CP47 to the D1–D2 heterodimer appears weakened and binding of bicarbonate on the PSII acceptor side is destabilized in the absence of the PsbH protein.
Effect of α1‐adrenergic stimulation of Cl− secretion and signal transduction in exocrine glands (Rana esculenta)
Authors: Gudme C.N. , Nielsen M.S. , Nielsen R.
Published: July 2002

In the present work, the effect of stimulation of α‐adrenergic receptors on Cl− secretion via exocrine frog skin glands was investigated. The α‐adrenergic stimulation was performed by addition of the adrenergic agonist noradrenaline in the presence of the β‐adrenergic antagonist propranolol. In the presence of propranolol, noradrenaline had no effect on the cellular cAMP content. The Cl− secretion was measured as the amiloride‐insensitive short circuit current (ISC). Addition of noradrenaline induced a biphasic increase in the ISC. The increase in ISC coincided with an increase in the net 36Cl− secretion. The noradrenaline‐induced increase in ISC was dose‐dependent with an EC50 of 13 ± 0.3 μM. Epifluorescence microscopic measurements of isolated, fura‐2‐loaded frog skin gland acini were used to characterize the intracellular calcium ([Ca2+]i) response. Application of noradrenaline induced a biphasic [Ca2+]i response, which was dose‐dependent with an EC50 of 11 ± 6 μM. The Ca2+ plateau unlike the peak‐response was sensitive to removal of Ca2+ from the extracellular medium. The noradrenaline‐induced increase in the Cl− secretion as well as in [Ca2+]i was sensitive to the α1‐adrenergic antagonist prazosine. Ryanodine and caffeine had no effect on [Ca2+]i indicating that the release was independent of ryanodine‐sensitive Ca2+ stores. Noradrenaline mediated a significant increase in the cellular inositol 1,4,5‐trisphosphate (IP3) content suggesting that the signal transduction pathway leading to the noradrenaline‐induced increase in Ca2+ involved IP3 and a release of Ca2+ from IP3‐sensitive stores.