bluuebunny/crossref_metadata_2025 huggingface dataset:
The inhibition by pertussis and tetanus toxins of evoked catecholamine release from intact and permeabilized bovine adrenal chromaffin cells
Authors: Bansal Mohinder K. , Phillips John H. , van Heyningen Simon
Published: July 2002

Pertussis toxin stimulates both basal and nicotine‐evoked catecholamine secretion from intact bovine adrenal chromaffin cells, as well as Ca2+‐evoked release from permeabilized cells. Tetanus toxin inhibits all these effects; it reduces the secretion of intact cells treated with pertussis toxin to the basal level, and decreases by about 50% Ca2+‐evoked release from permeabilized cells whether or not previously stimulated by pertussis toxin.
Molecular structure of the Japanese hepatitis C viral genome
Authors: Kato Nobuyuki , Hijikata Makoto , Nakagawa Mosanori , Ootsuyama Yuko , Muraiso Kanae , Ohkoshi Showgo , Shimotohno Kunitada
Published: July 2002

The amino acid sequence of the polyprotein deduced from the nucleotide sequence of the Japanese hepatitis C virus genome (N. Kato et. al. (1990) Proc. Natl. Acad. Sci. USA 87, 9524–9528)indicated that this virus is a member of a new class of positive‐stranded RNA viruses. Several domains of this polyprotein also showed weak homology with those of flaviviruses and pestiviruses including the chymotrypsin‐like serine proteinase. NTPase and RNA‐dependent RNA polymerase
Histone H4 acetylation in Drosophila Frequency of acetylation at different sites defined by immunolabelling with site‐specific antibodies
Authors: Munks Rebecca J.L. , Moore Jayne , O'Neill Laura P. , Turner Bryan M.
Published: July 2002

Electrophoresis, Western blotting and immunostaining with antibodies specific for histone H4 acetylated at lysines 5, 8, 12, or 16, were used to define patterns of H4 acetylation in cell lines from humans (HL60) and the fruit fly Drosophila (S2, Kc). In human cells, the mono‐acetylated isoform H4Ac1 is acetylated predominantly at just one of the four possible lysine residues, lysine 16. This is the first step in the progressive acetylation of H4. In contrast, in Drosophila, H4Ac1 is acetylated at lysines 5, 8, or 12 with approximately equal frequency. Fundamental differences appear to exist in control of H4 acetylation in different species, despite the evolutionary conservation of acetylation sites.
The apical sorting signal on human aminopeptidase N is not located in the stalk but in the catalytic head group
Authors: Vogel Lotte Katrine , Norén Ove , Sjöström Hans
Published: July 2002

Human aminopeptidase N carries an apical sorting signal on its ectodomain necessary for its correct transport to the apical membrane in Madin‐Darby canine kidney cells. To determine whether the apical sorting signal is localized in the serine/threonine rich stalk or in the catalytic head group, anchor/stalk‐minus aminopeptidase N, consisting of the hemagglutinin signal peptide and the catalytic head group of human aminopeptidase N, was expressed in MDCK cells. Anchor/stalk‐minus aminopeptidase N was secreted mainly to the apical side. The catalytic head group of human aminopeptidase N thus carries an apical sorting signal.
Specific antiviral activities of the human α interferons are determined at the level of receptor (IFNAR) structure
Authors: Mouchel-Vielh Emmanuèle , Lutfalla Georges , Mogensen Knud E. , Uzé Gilles
Published: July 2002

Differences in activity among the family of human IFNs α are much reduced if these ligands are assayed on bovine cells. In particular, the activity of IFN αD is much higher on bovine than on human cells. To examine these differences, the bovine counterpart of the human IFNAR has been cloned and expressed in a human cell line. The transfected cell line now recognizes the human IFN αD as a high‐specific‐activity IFN subtype, indicating that the differences in sensitivity between the bovine and human cells to the human IFN α lie in the structure of the IFNAR chain rather than in the other components of the functional receptor.
Endogenous nitric oxide induced by interleukin‐1β in rat islets of Langerhans and HIT‐T15 cells causes significant DNA damage as measured by the ‘comet’ assay
Authors: Delaney C.A. , Green M.H.L. , Lowe J.E. , Green I.C.
Published: July 2002

We have used the comet assay (single cell gel electrophoresis) to measure nitric oxide‐induced DNA damage in rat islets of Langerhans and insulin‐containing HIT‐T15 cells. Damage was induced following treatment with the nitric oxide donor SIN‐1, which also releases Superoxide, but was not reduced by exogenous Superoxide dismutase, suggesting that nitric oxide itself, rather than Superoxide or peroxynitrite may be the active species. The DNA damaging effect of nitric oxide was easily detectable at the earliest time point tested (15 min). Damage also resulted following induction of nitric oxide synthase by the cytokine interleukin‐1β in both islets and HIT‐T15 cells and was prevented by replacing the substrate, arginine, with nitromonomethyl arginine. Thus intracellular levels of nitric oxide generated by interleukin‐1β‐induced nitric oxide synthase were sufficient to cause DNA damage in islet cells and HIT‐T15 cells.
Truncated GroEL monomer has the ability to promote folding of rhodanese without GroES and ATP
Authors: Makino Yoshihide , Taguchi Hideki , Yoshida Masasuke
Published: July 2002

Similar to chaperonins from other sources, intact chaperonin from Escherichia coli (GroEL) exists as a tetradecamer, and the ability to promote folding of other proteins has been considered to be dependent on this oligomeric structure. However, the peptide fragments of GroEL of molecular size 34–50 kDa, which are produced by limited proteolysis of monomeric GroEL and are unable to assemble into an oligomer, retain the ability to promote folding of rhodanese even though the yield of productive folding is lower than the intact GroEL/GroES/ATP system. This promotion by truncated GroEL obeys rapid kinetics and does not require GroES and ATP.
In vitro complex formation between cholesterol and α1‐proteinase inhibitor
Authors: Janciauskiene Sabina , Eriksson Sten
Published: July 2002

The in vitro interaction between human (α1‐proteinase inhibitor (α1‐PI) and cholesterol was studied with electrophoretic and gel Chromatographic methods. The addition of cholesterol (from 1 to 20 mol/mol α1‐PI) at 37°C resulted in retarded electrophoretic mobility of α1‐PI towards the anode, diminished immunoreactivity and antiproteinase activity. At a molar ratio of 2:1 (cholesterol/α1 ‐PI), antitryptic activity was reduced by 15% but antielastase activity by 50%. At this ratio the gel filtration α1‐PI peak appeared at 67 kDa, as compared to 52 kDa for native α1‐pi. No size difference was noted on SDS‐PAGE. These results suggest the occurrence of noncovalent complex formation between cholesterol and α1‐PI in vitro.
Expression of fully active ammodytoxin A, a potent presynaptically neurotoxic phospholipase A2, in Escherichia coli
Authors: Liang Ning-Sheng , Pungerčar Jože , Križaj Igor , Štrukelj Borut , Gubenšek Franc
Published: July 2002

A cDNA encoding the most presynaptically neurotoxic phospholipase A2, ammodytoxin A, from the venom of the long‐nosed viper (Vipera ammodytes ammodytes) has been expressed in Escherichia coli. Ammodytoxin A was produced as a fusion protein with the 81 N‐terminal residues of adenylate kinase followed by the tetrapeptide recognition site for factor Xa (IEGR) just preceding the first amino acid residue of the toxin. The fusion protein was expressed under the control of tac promoter without IPTG induction in the form of insoluble inclusion bodies. It was dissolved in guanidine hydrochloride, S‐sulfonated and refolded in a reoxidation mixture including a reduced/oxidized glutathione redox couple. Ammodytoxin A was fully activated by limited hydrolysis with trypsin that preferentially cleaves the fusion protein at the factor Xa recognition site and purified by cation‐exchange chromatography. The correct N‐terminus was confirmed by protein sequencing. Recombinant ammodytoxin A has been proved to be indistinguishable from the native toxin in its enzymatic activity and toxicity.
Sodium benzylideneascorbate induces apoptosis in HIV‐replicating U1 cells
Authors: Aokia Kazumasa , Nakashima Hideki , Hattori Toshihiro , Shiokawa Daisuke , Ni-imi Ei-ichi , Tanimoto Yutaka , Maruta Hideharu , Uchiumi Fumiaki , Kochi Mutsuyuki , Yamamoto Naoki , Tanuma Sei-ichi
Published: July 2002

U1 cells, a subclone of U937 cells chronically infected with human immunodeficiency virus type 1 (HIV‐1), produced HIV‐1 only in the presence of inducers such as 12‐O‐tetradecanoxylphorbol 13‐acetate (TPA) or tumor necrosis factor (TNF)‐α. The expression of HIV‐antigen on U1 cells induced by TPA or TNF‐α was found to be prevented by sodium 5,6‐benzylidene‐l‐ascorbate (SBA) in a concentration‐dependent manner. Treatment of U1 cells with SBA in the presence of inducers resulted in cell death with cell shrinkage, chromatin condensation and DNA fragmentation into nucleosomal oligomers, characteristics of apoptosis. In contrast, SBA had scarcely any apoptotic effect on U1 cells in the absence of inducers. SBA did not also induce apoptosis in parental U937 cells in the presence or absence of inducers. These results suggest that HIV‐replicating U1 cells selectively undergo apoptosis on treatment with SBA.
Parallel β/α‐barrels of α‐amylase, cyclodextrin glycosyltransferase and oligo‐1,6‐glucosidase versus the barrel of β‐amylase: Evolutionary distance is a reflection of unrelated sequences
Authors: Janeček Štefan
Published: July 2002

The structures of functionally related β/α‐barrel starch hydrolases, α‐amylase, β‐amylase, cyclodextrin glycosyltransferase and oligo‐1,6‐glucosidase, are discussed, their mutual sequence similarities being emphasized. Since these enzymes (except for β‐amylase) along with the predicted set of more than ten β/α‐barrels from the α‐amylase enzyme superfamily fulfil the criteria characteristic of the products of divergent evolution, their unrooted distance tree is presented.
Specific characteristics of phosphofructokinase‐microtubule interaction
Authors: Vértessy Beata G. , Kovács János , Ovádi Judit
Published: July 2002

Muscle phosphofructokinase interacts with microtubule‐associated protein‐free microtubules resulting in a reduction of the overall activity of the enzyme [Lehotzky et al. (1993) J. Biol. Chem. 268,10888–10894] and periodical cross‐linking of the tubules [Lehotzky et al. (1994) Biochem. Biophys. Res. Commun. 204, 585–5911. Microtubule polymers of ‘tail‐free’ tubulin obtained by removal of the carboxy‐termini with limited subtilisin digestion retain the binding domains for phosphofructokinase that cross‐bridges microtubule ‘bodies’. Microtubule‐associated proteins bound on tubulin ‘tails’ do not perturb the kinase binding. These data suggest that the tubulin carboxy‐terminal domain is not involved in microtubule‐phosphofructokinase interactions and phosphofructokinase and microtubule‐associated proteins have distinct binding domains on microtubules. Of different isoforms of phosphofructokinase, occurring mainly in brain and tumor cells, the muscle isoform exhibits selective adsorption behaviour on microtubules. Phosphofructokinase M and C isoforms with different associative and allosteric properties may represent an auxiliary pathway to modulate energy production via glycolysis.
Developmental expression of tau proteins in the chicken and rat brain: Rapid down‐regulation of a paired helical filament epitope in the rat cerebral cortex coincides with the transition from immature to adult tau isoforms
Authors: Rösner Harald , Rebhan Michael , Vacun Gabriele , Vanmechelen Eugeen
Published: July 2002

The monoclonal antibodies TAU‐1 and AT8 are directed at human microtubule‐associated protein tau epitopes that contain a dephosphorylated and phosphorylated Ser202, respectively, while AT180 and AT270 are anti‐tau monoclonals with epitopes that require phosphorylated Thr181 and Thr231, respectively. We used these antibodies to study the developmental profiles of tau proteins in rat cerebral cortex and chicken optic lobes. In tau extracts from perinatal rat cerebral cortex, AT8 recognized one major protein band of approximately 50 kDa that peaks on postnatal day 6 and declines rapidly to lower levels at day 12. At later stages, the AT8 epitope was expressed by several adult tau isoforms that were, however, stained only very faintly in highly enriched samples. Two additional tau epitopes recognized by AT180 and AT270 were found to be expressed by one or two protein bands up to about postnatal day 19 and then declined. Unlike the AT8 epitope, in the mature brain these epitopes were stained strongly in enriched samples, where they were expressed by a greater number of adult isoforms. Between embryonic day 19 and postnatal day 12, TAU‐1 was found to recognize one major protein band of approximately 50 kDa which migrated slightly faster than the AT8‐binding band. At postnatal day 19 and all older stages (including adult cortex), at least three additional TAU‐1‐binding isoforms with higher apparent molecular weights were present. Hence, the transition from one immature to several adult TAU‐1‐binding tau isoforms between postnatal day 12 and 19 in rat cerebral cortex coincides with the phase of rapid down‐regulation of the AT8 epitope. As in the rat cerebrum, in chicken optic lobes there is a developmental decrease of AT8‐binding proteins which is paralleled by striking changes in the electrophoretic pattern of tau isoforms recognized by TAU‐1. In both rat cerebral cortex and chicken optic lobes, the period of maximal expression of AT8‐binding tau is morphologically characterized by intense axonal growth and beginning synaptogenesis, whereas its subsequent rapid down‐regulation and the appearance of novel TAU‐1‐binding isoforms correlates with synaptic maturation, the onset of spontaneous electrical activity and the beginning of myelination.
Case management: a critical review of the outcome literature
Authors: Holloway F , Oliver N , Collins E , Carson J
Published: July 2002

Case management has been an integral part of psychiatric practice in the United States for over a decade and has generated a large body of literature. The application of case management principles to the care of people suffering from psychiatric disorders is becoming increasingly popular in the United Kingdom and Europe and literature is now beginning to be published. However, no definitive statements about the efficacy of case management have been made due to a range of conceptual and methodological problems. The present paper is a critical review of the case management outcome literature. Reported outcomes are reviewed in the context of study design and service characteristics. The authors conclude that case management practice can have at least some impact on patients' use of services (including marked decrease in in-patient bed days); satisfaction with services; engagement with services; and social networks and relationships when it is delivered as a direct, clinical service with high staff: patient ratios. A set of recommendations are suggested for the future practice and presentation of research into case management.
The monomeric polypeptide comprises the functional flavanone 3β‐hydroxylase from Petunia hybrida
Authors: Lukačin Richard , Urbanke Claus , Gröning Inga , Matern Ulrich
Published: July 2002

Flavanone 3β‐hydroxylase catalyzes the FeII/oxoglutarate‐dependent hydroxylation of (2S)‐flavanones to (2R,3R)‐dihydroflavonols in the biosynthesis of flavonoids, catechins and anthocyanidins. The enzyme had been partially purified from Petunia hybrida and proposed to be active as a dimer of roughly 75 kDa in size. More recently, the Petunia 3β‐hydroxylase was cloned and shown to be encoded in a 41 655 Da polypeptide. In order to characterize the molecular composition, the enzyme was expressed in a highly active state in Escherichia coli and purified to apparent homogeneity. Size exclusion chromatographies of the pure, recombinant enzyme revealed that this flavanone 3β‐hydroxylase exists in functional monomeric and oligomeric forms. Protein cross‐linking experiments employing a specific homobifunctional sulfhydryl group reagent or the photochemical activation of tryptophan residues confirmed the tendency of the enzyme to aggregate to oligomeric complexes in solution. Thorough equilibrium sedimentation analyses, however, revealed a molecular mass of 39.2±12 kDa for the recombinant flavanone 3β‐hydroxylase. The result implies that the monomeric polypeptide comprises the catalytically active flavanone 3β‐hydroxylase of P. hybrida, which may readily associate in vivo with other proteins.
Activation of melanogenesis by vacuolar type H+‐ATPase inhibitors in amelanotic, tyrosinase positive human and mouse melanoma cells
Authors: Ancans Janis , Thody Anthony J
Published: July 2002

In this study, we describe the activation of melanogenesis by selective vacuolar type H+‐ATPase inhibitors (bafilomycin A1 and concanamycin A) in amelanotic human and mouse melanoma cells which express tyrosinase but show no melanogenesis. Addition of the inhibitors activated tyrosinase within 4 h, and by 24 h the cells contained measurable amounts of melanin. These effects were not inhibited by cycloheximide (2 μg/ml) which is consistent with a post‐translational mechanism of activation. Our findings suggest that melanosomal pH could be an important and dynamic factor in the control of melanogenesis in mammalian cells.
The photoreceptor protein of Euglena gracilis
Authors: Barsanti Laura , Passarelli Vincenzo , Walne Patricia L. , Gualtieri Paolo
Published: July 2002

We isolated the photoactive protein Erh, isolated from the photoreceptor of the unicellular photosynthetic flagellate Euglena gracilis. It is a 27 kDa protein with a photocycle resembling that of sensory rhodopsin, but with at least one stable intermediate. We recorded the absorption spectrum of the parent form of this protein both under native form and in the presence of hydroxylamine and sodium borohydride, and the fluorescence spectra of both the parent and intermediate forms. We suggest that Erh is a rhodopsin‐like protein and propose a simple photocycle. This protein shows optical bistability, without thermal deactivation.
Mutations at the arginine residues in α8 loop of Bacillus thuringiensis δ‐endotoxin Cry1Ac affect toxicity and binding to Manduca sexta and Lymantria dispar aminopeptidase N
Authors: Lee Mi Kyong , Jenkins Jeremy L. , You Taek H. , Curtiss April , Son Joo J. , Adang Michael J. , Dean Donald H.
Published: July 2002

The functional role of the α8 loop residues in domain II of Bacillus thuringiensis Cry1Ac toxin was examined. Alanine substitution mutations were introduced in the residues from 275 to 293. Among the mutant toxins, substitutions at R281 and R289 affected toxicity to Manduca sexta and Lymantria dispar. Loss of toxicity by these mutant toxins was well correlated with reductions in binding affinity for brush border membrane vesicles and the purified receptor, aminopeptidase N (APN), from both insects. These data suggest that the two arginine residues in the α8 loop region are important in toxicity and APN binding in L. dispar and M. sexta.
The transmembrane protein tyrosine phosphatase α dephosphorylates the insulin receptor in intact cells
Authors: Lammers Reiner , Møller Niels Peter H. , Ullrich Axel
Published: July 2002

© 1997 Federation of European Biochemical Societies.
Protein modification by a Maillard reaction intermediate methylglyoxal
Authors: Uchida Koji , Khor Ooi Thiang , Oya Tomoko , Osawa Toshihiko , Yasuda Yoshinari , Miyata Toshio
Published: July 2002

Methylglyoxal (MG), an endogenous metabolite that increases in diabetes, is a common intermediate in nonenzymatic glycation (Maillard reaction) in vivo. Here we describe the immunochemical approach to the detection of MG adducts in proteins in vitro and in atherosclerotic lesions of human aorta in vivo. The reaction of protein (bovine serum albumin) with MG led to selective loss of arginine and lysine residues, accompanied by the formation of 5‐methylimidazolone (N

δ
‐(5‐methylimidazolon‐2‐yl)ornithine) and imidazolysine (1,3‐di‐lysino‐4‐methylimidazole) derivatives, respectively. The anti‐5‐methylimidazolone antibody was prepared by immunizing rabbits with a MG‐keyhole limpet hemocyanin conjugate and purifying the serum on an affinity gel prepared by covalent attachment of the 5‐methylimidazolone derivative. The antibody cross‐reacted with the proteins treated with not only MG but trioses, such as hydroxyacetone, dihydroxyacetone, and glyceraldehyde. The immunohistochemical analysis revealed that atherosclerotic lesions of human aorta contained 5‐methylimidazolone derivatives whose distributions were identical to those of advanced glycation end products (AGEs) detected by the anti‐AGE antibody.
Mutations in subunit 6 of the F1F0‐ATP synthase cause two entirely different diseases
Authors: Majander Anna , Lamminen Tarja , Juvonen Vesa , Aula Pertti , Nikoskelainen Eeva , Savontaus Marja-Liisa , Wikström Mårten
Published: July 2002

A lowered efficiency of oxidative phosphorylation was recently found in a Leber hereditary optic neuropathy (LHON) proband carrying a mutation in the mtDNA gene for subunit 6 of the membrane‐bound F0 segment of the F1F0‐ATP synthase [9]. This phenotype was transferred to cytoplasmic hybrid cells together with the mutation, proving its functional significance. Increasing the respiratory rate in the mitochondria from this mutant raised the ATP/2e− ratio back to normal values. A different mutation in the same mtDNA gene has been found in patients with the NARP syndrome [10]. Although the ATP/2e− ratio is also decreased in this mutant, in this case an increase in the respiratory rate could not compensate for it. Whilst both mutations affect subunit 6 of the proton‐translocating F0 segment, the LHON mutation induces a proton leak whereas the NARP mutation blocks proton translocation. Hence, the latter will have much more destructive metabolic consequences in agreement with the large clinical differences between the two diseases.
The first constant domain (CH1 and CL) of an antibody used as heterodimerization domain for bispecific miniantibodies
Authors: Müller Kristian M , Arndt Katja M , Strittmatter Wolfgang , Plückthun Andreas
Published: July 2002

Bispecific miniantibodies were constructed by genetically fusing the CH1 domain of an IgG1 to the C‐terminus of a single‐chain Fv fragment (scFv‐425), specific for the EGF receptor, and fusing the CL domain of a kappa light chain to the C‐terminus of a scFv specific for CD2 (scFv‐M1). An efficient dicistronic gene arrangement for functional expression in Escherichia coli was constructed. Immunoblots demonstrated correct domain assembly and the formation of the natural CH1‐CL disulfide bridge. Gel filtration confirmed the correct size, sandwich ELISAs demonstrated bispecific functionality, and SPR biosensor measurements determined binding to EGF‐R in comparison to bivalent constructs. Bispecific anti‐EGF‐R/anti‐CD2 miniantibodies are candidates for the immunotherapy of cancer.
Overexpression of lactate dehydrogenase A attenuates glucose‐induced insulin secretion in stable MIN‐6 β‐cell lines
Authors: Zhao Chao , Rutter Guy A
Published: July 2002

Since islet β‐cells express little l‐lactate dehydrogenase (LDH) activity, we have examined the effects on these cells of LDH overexpression. In mock‐transfected MIN6 β‐cells, LDH activity was 38 nmol/min/mg protein, and 30 mM glucose stimulated secretion 10.4‐fold. In two MIN6 cell clones stably overexpressing human LDH‐A cDNA, insulin secretion was stimulated only 2.7‐ and 2.1‐fold by high glucose. K+‐stimulated insulin secretion was unaffected, and leucine stimulation enhanced, by LDH‐A overexpression. LDH‐A‐overexpressing clones displayed unaltered activities of hexokinase, glucokinase, and malate dehydrogenase, slightly elevated plasma membrane lactate transport activity, and lowered insulin content. Low LDH activity would therefore appear important in β‐cell glucose sensing.
Competitive inhibition analysis of the enzyme‐substrate interaction in the carboxy‐terminal processing of the precursor D1 protein of photosystem II reaction center using substituted oligopeptides
Authors: Yamamoto Yumiko , Satoh Kimiyuki
Published: July 2002

A clear parallelism was demonstrated between the efficiency as substrate of the substituted oligopeptides corresponding to the carboxy‐terminal (C‐terminal) sequence of the precursor D1 protein (pD1) in the in vitro enzymatic assay and their competitive inhibitory capacity toward the proteolytic C‐terminal processing of the full‐length pD1 integrated in the intact photosystem II complex embedded in the thylakoid membrane of Scenedesmus obliquus LF‐1 mutant, as shown e.g. by the influence of L343A, A345G and A345V substitutions and the effect of C‐terminal fragments. This suggests that the basic mechanism for substrate recognition by the processing protease elucidated in the enzymatic analysis using synthetic oligopeptides is also effective in vivo, although it can sometimes be difficult to detect the consequence of amino acid substitution in the integrated systems.
Glucose stimulates the activation domain potential of the PDX‐1 homeodomain transcription factor
Authors: Petersen Helle V , Peshavaria Mina , Pedersen Anette A , Philippe Jacques , Stein Roland , Madsen Ole D , Serup Palle
Published: July 2002

Glucose‐stimulated expression of the insulin gene in β cells is mediated by the PDX‐1 transcription factor. In this report, we show that stimulation results from effects on activation and DNA‐binding potential. Thus, glucose specifically stimulated expression in MIN6 β cells from chimeras of PDX‐1 and the GAL4 DNA‐binding domain which spanned the N‐terminal PDX‐1 activation domain located between amino acids 1 to 79. GAL4:PDX activity was induced over physiological glucose concentrations and was also regulated by effectors of this response. The level of endogenous PDX‐1 binding and phosphorylation were also induced under these conditions. We discuss how changes in PDX‐1 phosphorylation may influence activity in glucose‐treated β cells.
A dimeric bispecific miniantibody combines two specificities with avidity
Authors: Müller Kristian M. , Arndt Katja M. , Plückthun Andreas
Published: July 2002

Bispecific antibodies extend the capabilities of nature and might be applied in immunotherapy and biotechnology. By fusing the gene of a single‐chain Fv (scFv) fragment to a helical dimerization domain, followed by a second scFv fragment of different specificity, we were able to express a functional protein in E. coli, which is bispecific and has two valencies for each specificity. The dimeric bispecific (DiBi) miniantibody preserves the natural avidity of antibodies in a very small‐sized molecule of only 120 kDa. The generality of the principle was shown with a scFv fragment binding the EGF‐receptor (named scFv 425) in three combinations with scFv fragments either directed against CD2 (ACID2.M1), phosphorylcholine (McPC603) or fluorescein (FITC‐E2). Binding was analyzed by sandwich surface plasmon resonance biosensor (BIAcore) measurements.
Prevalence of ‘high risk’ human papillomavirus in the lower genital tract of Brazilian gravidas
Authors: Armbruster‐Moraes E , Ioshimoto L.M , Leao E , Zugaib M
Published: July 2002

The presence of high‐risk human Papillomavirus types 16, 18 and 33 was examined in 125 pregnant patients with abnormal Papanicolau smears. Specimens of cervicovaginal cells were analyzed by a simplified method of slot‐blot hybridization. The overall prevalence of those viral sequences was 48%, being: 22.4% of HPV16, 17.6% of HPV18, 4.0% for double HPV16 and 18 infestation and 4.0% of HPV33. Their prevalence in HPV positive cervical sample was alone respectively 46.6%, 36.6%, 8.3% and 8.3%. Besides the high incidence of those carcinogenic types and intense viral proliferation, a rapid progression from CIN to carcinoma was clinically observed in four pregnant patients. Our data may reinforce the idea that progesterone has a positive role to the persistence and transformation of ‘high risk’ HPV, particularly of HPV16. The enhanced detection of potentially malignant types during pregnancy should warn on the importance of early diagnosis and treatment of papillomatosis.
Gender and activation level in smokers
Authors: Daurignac E. , Perez-Diaz F. , Grillon C. , Jouvent R.
Published: July 2002

Studies on the enhancing effects of nicotine on performance are usually pharmacological challenges using deprived male smokers. However, gender may be a factor that influences nicotine/smoking effects upon information processing. We investigated gender differences in contingent negative variation (CNV) amplitude in non-deprived dependent smokers performing a go-no go reaction time paradigm. Female smokers did not differ from female non-smokers in both early and late CNV, whereas male smokers presented greater early and late CNV compared to male non-smokers and an alteration in inhibiting processes responsible for CNV development in the no go condition. Consistent with the evidence of gender differences in nicotine/smoking sensitivity, these preliminary results emphasize the need for taking into account gender in psychophysiological research of nicotine/smoking effects.
Fatigue‐resistant Fe‐Mn‐Si‐based alloy seismic dampers to counteract long‐period ground motion
Authors: Inoue Yasuhiko , Kushibe Atsumichi , Umemura Kenji , Mizushima Yasunori , Sawaguchi Takahiro , Nakamura Terumi , Otsuka Hiroaki , Chiba Yuya
Published: September 2020

In recent years, resonance in high‐rise buildings due to long‐period ground motion, which induces large‐amplitude cyclic deformation of seismic dampers, has become a matter of significant concern. Performance requirements for seismic dampers that are installed in vibration‐controlled buildings have become more stringent, and durability against cyclic deformation has become essential. An Fe‐15Mn‐4Si‐10Cr‐8Ni alloy with enhanced low‐cycle fatigue resistance has been developed to produce steel seismic dampers that are durable against large‐amplitude cyclic deformations. We used this alloy to develop two types of fatigue‐resistant seismic dampers (shear panel and brace‐type) that counteract long‐period ground motion. Furthermore, cyclic loading tests were conducted to validate the deformation performance and fatigue resistance of the developed damper. The results indicated that these dampers exhibit significantly better fatigue life than conventional steel dampers and exhibit outstanding deformation performance and durability under low‐cycle fatigue. The proposed two types of dampers were installed on steel structure buildings in Japan. These dampers ensured that the buildings with seismic performance margins can withstand long‐period and long‐duration ground motion and repeated after‐quakes.
Strategies in the Analysis of Plant Flavonoids: An Update
Authors: Santos‐Buelga Celestino , González Paramás Ana M.
Published: September 2020

Flavonoids are one of the largest groups of plant secondary metabolites. They comprise several thousand compounds that share a phenylchromane skeleton and can be classified into different classes, namely flavones, flavonols, flavanones, flavanols, anthocyanins, dihydroflavonols, isoflavones, and chalcones. Flavonoids occur in their natural sources as aglycones or glycosylated forms and as monomers or constituting polymerized structures and can be found both as free and matrix‐bound compounds. This structural diversity affects their physicochemical behavior, and different flavonoid classes and compounds may have different requisites for their extraction and analysis, so that there is not a unique analytical strategy that applies in all situations. In this article, the main methodological approaches to the analysis of flavonoids in plant materials are revised. Particular attention is paid to more recent extraction techniques and high‐performance liquid chromatography (LC)‐based methodologies coupled to different detection systems, and especially liquid chromatography coupled to mass spectrometry (LC‐MS) that currently dominates the field of flavonoid analysis.
Efficacy of Ciprofloxacin/Celecoxib combination in zebrafish models of amyotrophic lateral sclerosis
Authors: Goldshtein Hagit , Muhire Alexandre , Petel Légaré Virginie , Pushett Avital , Rotkopf Ron , Shefner Jeremy M. , Peterson Randall T , Armstrong Gary A. B. , Russek‐ Blum Niva
Published: September 2020

Objective

To evaluate the efficacy of a fixed‐dose combination of two approved drugs, Ciprofloxacin and Celecoxib, as a potential therapeutic treatment for amyotrophic lateral sclerosis (ALS).

Methods

Toxicity and efficacy of Ciprofloxacin and Celecoxib were tested, each alone and in distinct ratio combinations in SOD1 G93R transgenic zebrafish model for ALS. Quantification of swimming measures following stimuli, measurements of axonal projections from the spinal cord, neuromuscular junction structure and morphometric analysis of microglia cells were performed in the combination‐ treated vs nontreated mutant larvae. Additionally, quantifications of touch‐evoked locomotor escape response were conducted in treated vs nontreated zebrafish expressing the TARDBP G348C ALS variant.

Results

When administered individually, Ciprofloxacin had a mild effect and Celecoxib had no therapeutic effect. However, combined Ciprofloxacin and Celecoxib (Cipro/Celecox) treatment caused a significant increase of ~ 84% in the distance the SOD1 G93R transgenic larvae swam. Additionally, Cipro/Celecox elicited recovery of impaired motor neurons morphology and abnormal neuromuscular junction structure and preserved the ramified morphology of microglia cells in the SOD1 mutants. Furthermore, larvae expressing the TDP‐43 mutation displayed evoked touch responses that were significantly longer in swim distance (110% increase) and significantly higher in maximal swim velocity (~44% increase) when treated with Cipro/Celecox combination.

Interpretation

Cipro/Celecox combination improved locomotor and cellular deficits of ALS zebrafish models. These results identify this novel combination as effective, and may prove promising for the treatment of ALS.
Inducing Endoplasmic Reticulum Stress to Expose Immunogens: A DNA Tetrahedron Nanoregulator for Enhanced Immunotherapy
Authors: Li Yanhua , Zhang Xia , Wan Xiuyan , Liu Xiaohan , Pan Wei , Li Na , Tang Bo
Published: September 2020

Immunogenic cell death (ICD) is an important modulation type for stimulating anticancer immune responses and amplifying immunotherapy efficacy. When ICD occurs, endoplasmic reticulum (ER) stress plays a vital role for exposing immunogens. Herein, a functionalized DNA tetrahedron nanoregulator to specifically trigger ER stress for enhancing cancer immunotherapy is designed. The nanoregulator can target ER organelles by binding to the sulfonamide receptor of cancer cells. Then glucose depletion and reactive oxygen species generation cause a strong ER stress response to induce ICD to expose tumor immunogens. Thereafter, the dendritic cell (DC) maturation is promoted, and T cell proliferation and infiltration are stimulated to advance cancer immunotherapy. Combined with immune checkpoint inhibitor (α‐PD‐1), the ER stress triggered nanoregulator exhibits significant suppression for breast cancer and melanoma.
High‐Performance Li–O2 Batteries Based on All‐Graphene Backbone
Authors: Ma Yong , Wei Le , Gu Yuting , Hu Jiapeng , Chen Yujie , Qi Pengwei , Zhao Xiaohui , Peng Yang , Deng Zhao , Liu Zhongfan
Published: September 2020

The Li–O2 battery is one of the most captivating energy storage forms due to its extraordinarily high energy density and the readily its the ready availability of oxygen. However, significant challenges lie ahead on both the anode and cathode sides before the technology can be finally deployed to benefit human life. Herein, a two‐birds‐one‐stone tactic is implemented to fabricate high‐performance and flexible Li–O2 batteries utilizing only one structural backbone composed of graphene oxide aerogel embedding hollow NiCo2O4 microspheres for both the anode and cathode. While the composite Li anode fabricated through lithium infusion exhibits an ultrahigh capacity of 3398.4 mAh g−1 and significantly inhibits dendrite growth and volume expansion, the freestanding oxygen cathode demonstrates great capability in promoting energy efficiency by catalyzing reversible Li2O2 formation. When coupled together, the resultant Li–O2 batteries manifest a superb long‐term cycling stability with highly reversible discharge/charge for more than 400 cycles, apart from the remarkable mechanical deformability demonstrated by flexible pouch cells. By employing a full spectrum of ex situ and operando spectroscopic and microscopic tools, mechanistic insights into the remarkable Li–O2 performance are given.
Ultrathin and Robust Hydrogel Coatings on Cardiovascular Medical Devices to Mitigate Thromboembolic and Infectious Complications
Authors: Parada German , Yu Yan , Riley William , Lojovich Sarah , Tshikudi Diane , Ling Qing , Zhang Yefang , Wang Jiaxin , Ling Lei , Yang Yueying , Nadkarni Seemantini , Nabzdyk Christoph , Zhao Xuanhe
Published: September 2020

Thromboembolic and infectious complications stemming from the use of cardiovascular medical devices are still common and result in significant morbidity and mortality. There is no strategy to date that effectively addresses both challenges at the same time. Various surface modification strategies (e.g., silver, heparin, and liquid‐impregnated surfaces) are proposed yet each has several limitations and shortcomings. Here, it is shown that the incorporation of an ultrathin and mechanically robust hydrogel layer reduces bacterial adhesion to medical‐grade tubing by 95%. It is additionally demonstrated, through a combination of in vitro and in vivo tests, that the hydrogel layer significantly reduces the formation and adhesion of blood clots to the tubing without affecting the blood's intrinsic clotting ability. The adhesion of clots to the tubing walls is reduced by over 90% (in vitro model), which results in an ≈60% increase in the device occlusion time (time before closure due to clot formation) in an in vivo porcine model. The advantageous properties of this passive coating make it a promising surface material candidate for medical devices interfacing with blood.
Biofabrication of Hepatic Constructs by 3D Bioprinting of a Cell‐Laden Thermogel: An Effective Tool to Assess Drug‐Induced Hepatotoxic Response
Authors: Gori Manuele , Giannitelli Sara M. , Torre Miranda , Mozetic Pamela , Abbruzzese Franca , Trombetta Marcella , Traversa Enrico , Moroni Lorenzo , Rainer Alberto
Published: September 2020

A thermoresponsive Pluronic/alginate semisynthetic hydrogel is used to bioprint 3D hepatic constructs, with the aim to investigate liver‐specific metabolic activity of the 3D constructs compared to traditional 2D adherent cultures. The bioprinting method relies on a bioinert hydrogel and is characterized by high‐shape fidelity, mild depositing conditions and easily controllable gelation mechanism. Furthermore, the dissolution of the sacrificial Pluronic templating agent significantly ameliorates the diffusive properties of the printed hydrogel. The present findings demonstrate high viability and liver‐specific metabolic activity, as assessed by synthesis of urea, albumin, and expression levels of the detoxifying CYP1A2 enzyme of cells embedded in the 3D hydrogel system. A markedly increased sensitivity to a well‐known hepatotoxic drug (acetaminophen) is observed for cells in 3D constructs compared to 2D cultures. Therefore, the 3D model developed herein may represent an in vitro alternative to animal models for investigating drug‐induced hepatotoxicity.
Nitrone/Imine Selectivity Switch in Base‐Catalysed Reaction of Aryl Acetic Acid Esters with Nitrosoarenes: Joint Experimental and Computational Study
Authors: Volpe Chiara , Meninno Sara , Roselli Angelo , Mancinelli Michele , Mazzanti Andrea , Lattanzi Alessandra
Published: September 2020

Herein we report a mild and diastereoselective access to ketonitrones by reacting easily available aryl acetic acid esters and other active methylene compounds, with nitrosoarenes under catalytic loading of 2‐tert‐butylimino‐2‐diethylamino‐1,3‐dimethylperhydro‐1,3,2‐diazaphosphorine (BEMP) at room temperature. Depending on the substitution pattern and nature of the aryl moiety, a switch toward the formation of imines can be observed. The mechanistic framework is put to scrutiny by experimental and theoretical studies, pointing to the formation of a nitroso aldol intermediate, whose fate toward one of the competing pathways, namely hydride transfer or elimination, would depend upon the NOH/CHα relative acidities.

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The time course of physiological adaptations to high‐intensity interval training in older adults
Authors: Herrod Philip J. J. , Blackwell James E. M. , Boereboom Catherine L. , Atherton Philip J. , Williams John P. , Lund Jonathan N. , Phillips Bethan E.
Published: September 2020

Objective

High‐intensity interval training (HIIT) has been shown to be more effective than moderate continuous aerobic exercise for improving cardiorespiratory fitness (CRF) in a limited time frame. However, the length of time required for HIIT to elicit clinically significant improvements in the CRF of older adults is currently unknown. The aim of this study was to compare changes in the CRF of older adults completing identical HIIT protocols of varying durations.

Methods

Forty healthy, community‐dwelling older adults completed a cardiopulmonary exercise test (CPET) before and after 2, 4, or 6 weeks of fully supervised HIIT on a cycle ergometer, or a no‐intervention control period.

Results

Anaerobic threshold (AT) was increased only after 4 (+1.9 [SD 1.1] mL/kg/min) and 6 weeks (+1.9 [SD 1.8] mL/kg/min) of HIIT (both P < 0.001), with 6‐week HIIT required to elicit improvements in VO2 peak (+3.0 [SD 6] mL/kg/min; P = 0.04). Exercise tolerance increased after 2 (+15 [SD 15] W), 4 (+17 [SD 11] W), and 6 weeks (+16 [SD 11] W) of HIIT (all P < 0.001), with no difference in increase between the groups. There were no changes in any parameter in the control group.

Conclusion

Improvements in exercise tolerance from HIIT precede changes in CRF. Just 4 weeks of a well‐tolerated, reduced‐exertion HIIT protocol are required to produce significant changes in AT, with a further 2 weeks of training also eliciting improvements in VO2 peak.
The Brain Chart of Aging: Machine‐learning analytics reveals links between brain aging, white matter disease, amyloid burden, and cognition in the iSTAGING consortium of 10,216 harmonized MR scans
Authors: Habes Mohamad , Pomponio Raymond , Shou Haochang , Doshi Jimit , Mamourian Elizabeth , Erus Guray , Nasrallah Ilya , Launer Lenore J. , Rashid Tanweer , Bilgel Murat , Fan Yong , Toledo Jon B. , Yaffe Kristine , Sotiras Aristeidis , Srinivasan Dhivya , Espeland Mark , Masters Colin , Maruff Paul , Fripp Jurgen , Völzk Henry , Johnson Sterling C. , Morris John C. , Albert Marilyn S. , Miller Michael I. , Bryan R. Nick , Grabe Hans J. , Resnick Susan M. , Wolk David A. , Davatzikos Christos ,   for the iSTAGING consortium, the Preclinical AD consortium, the ADNI, and the CARDIA studies
Published: September 2020

Introduction

Relationships between brain atrophy patterns of typical aging and Alzheimer's disease (AD), white matter disease, cognition, and AD neuropathology were investigated via machine learning in a large harmonized magnetic resonance imaging database (11 studies; 10,216 subjects).

Methods

Three brain signatures were calculated: Brain‐age, AD‐like neurodegeneration, and white matter hyperintensities (WMHs). Brain Charts measured and displayed the relationships of these signatures to cognition and molecular biomarkers of AD.

Results

WMHs were associated with advanced brain aging, AD‐like atrophy, poorer cognition, and AD neuropathology in mild cognitive impairment (MCI)/AD and cognitively normal (CN) subjects. High WMH volume was associated with brain aging and cognitive decline occurring in an ≈10‐year period in CN subjects. WMHs were associated with doubling the likelihood of amyloid beta (Aβ) positivity after age 65. Brain aging, AD‐like atrophy, and WMHs were better predictors of cognition than chronological age in MCI/AD.

Discussion

A Brain Chart quantifying brain‐aging trajectories was established, enabling the systematic evaluation of individuals’ brain‐aging patterns relative to this large consortium.
Biallelic Intronic AAGGG Expansion of RFC1 is Related to Multiple System Atrophy
Authors: Wan Linlin , Chen Zhao , Wan Na , Liu Mingjie , Xue Jin , Chen Hongsheng , Zhang Youming , Peng Yun , Tang Zhichao , Gong Yiqing , Yuan Hongyu , Wang Shang , Deng Qi , Hou Xuan , Wang Chunrong , Peng Huirong , Shi Yuting , Peng Linliu , Lei Lijing , Duan Ranhui , Xia Kun , Qiu Rong , Shen Lu , Tang Beisha , Ashizawa Tetsuo , Jiang Hong
Published: September 2020

Objective

A recessive biallelic repeat expansion, (AAGGG)exp, in the RFC1 gene has been reported to be a frequent cause of late‐onset ataxia. For cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS), the recessive biallelic (AAGGG)exp genotype was present in ~92% of cases. This study aimed to examine whether the pentanucleotide repeat (PNR) was related to multiple system atrophy (MSA), which shares a spectrum of symptoms with CANVAS.

Methods

In this study, we screened the pathogenic (AAGGG)exp repeat and 5 other PNRs in 104 Chinese sporadic adult‐onset ataxia of unknown aetiology (SAOA) patients, 282 MSA patients, and 203 unaffected individuals. Multiple molecular genetic tests were used, including long‐range polymerase chain reaction (PCR), repeat‐primed PCR (RP‐PCR), Sanger sequencing, and Southern blot. Comprehensive clinical assessments were conducted, including neurological examination, neuroimaging, nerve electrophysiology, and examination of vestibular function.

Results

We identified biallelic (AAGGG)exp in 1 SAOA patient and 3 MSA patients. Additionally, 1 MSA patient had the (AAGGG)exp/(AAAGG)exp genotype with uncertain pathogenicity. We also described the carrier frequency for different PNRs in our cohorts. Furthermore, we summarized the distinct phenotypes of affected patients, suggesting that biallelic (AAGGG)exp in RFC1 could be associated with MSA and should be screened routinely in the MSA diagnostic workflow.

Interpretation

Our results expanded the clinical phenotypic spectrum of RFC1‐related disorders and raised the possibility that MSA might share the same genetic background as CANVAS, which is crucial for re‐evaluating the current CANVAS and MSA diagnostic criteria. ANN NEUROL 2020;88:1132–1143
Post‐Synthetic Modification: Systematic Study on a Simple Access to Nitridophosphates
Authors: Wendl Sebastian , Seidl Lisa , Schüler Patrick , Schnick Wolfgang
Published: September 2020

Nitridophosphates are a well‐studied class of nitrides with diverse materials properties, such as luminescence or ion conductivity. Despite the growing interest in this compound class, their synthesis mostly works through direct combination of starting materials. Herein, we present a systematic study on a promising method for post‐synthetic modification by treating pre‐synthesized nitridophosphates with halides under elevated pressures and temperatures. Herein, we focus on the applicability of this approach to P/N compounds with different degrees of condensation. Accordingly, BaP2N4, Ba3P5N10Br, SrH4P6N12, CaP8N14, and Ca2PN3are investigated as model compounds for framework‐, layer‐, and chain‐type nitridophosphates. The formation of structurally related, as well as, completely unrelated compounds, compared to the starting materials, shows the great potential of the approach, which increases the synthetic possibilities for nitridophosphates significantly.