bluuebunny/crossref_metadata_2025 huggingface dataset:
Size and domain structure of collagen VI produced by cultured fibroblasts
Authors: Aumailley Monique , von der Mark Helga , Timpl Rupert
Published: July 2002

Disulfide‐bonded forms of collagen VI were analyzed by immunoblotting of fibroblast culture medium and cell extracts. The protein consists of pepsin and collagenase‐resistant domains of about equal size indicating a molecular mass of 340 kDa for collagen VI monomers.
Comparative calcium binding and conformational studies of turkey and rabbit skeletal troponin C
Authors: McCubbin William D. , Oikawa Kimio , Kay Cyril M.
Published: July 2002

Troponin C from turkey skeletal muscle has been compared with its chicken counterpart in terms of amino acid composition and fragmentation patterns and with rabbit TN‐C by Ca2+ binding and conformational response to Ca2+ as monitored by CD and fluorescence. Cyanogen bromide and tryptic digestion mixtures of chicken and turkey TN‐C have been separated by reversed‐phase HPLC. The similarity of the elution profiles, along with the almost identical amino acid compositional data, suggest that the sequences are essentially equivalent. Both turkey and rabbit TN‐C bound 2 mol Ca2+/mol protein at pH 5.3, while at pH 6.8, this figure was raised to 4 mol/mol protein. Circular dichroism and fluorescence measurements indicated that the conformations of the two proteins responded in a very similar manner to the presence of Ca2+
A plausible mechanism for flagellar rotation in bacteria
Authors: Wagenknecht Terence
Published: July 2002

A novel model for the action of the flagellar motor of bacteria is presented in which rotational motion is produced by conformational changes in a helically or rotationally symmetric multi‐subunit component of the basal body. The model is consistent with the known properties of the motor, including its ability to rotate equally well clockwise and counterclockwise. Formally, the model is similar to mechanisms that have been proposed for other biologic transducers of free energy, such as active transporters.
Binding of ATP to nucleoside‐diphosphate kinase: a kinetic study
Authors: Lascu Ioan , Presecan Elena , Proinov Ioan
Published: July 2002

The binding of nucleotides to pig heart nucleoside‐diphosphate kinase was studied using Rose Bengal as an optical probe. ATP, in the absence of Mg2+, binds slowly to the enzyme, with a second order rate constant of about 3000 M−1·s−1, whereas in its presence the binding is much faster. This finding suggests the regulation of the nucleoside‐diphosphate kinase activity by uncomplexed ATP, and that ATP binds normally to the enzyme via a metal ion bridge.
Phorbol ester inhibition of vasopressin‐induced calcium efflux from cultured rat aortic myocytes
Authors: Lassegue Bernard , Stoclet Jean-Claude
Published: July 2002

The effect of the protein kinase C activator TPA was investigated on AVP‐induced 45Ca release from rat aortic myocytes. In the nanomolar range TPA, but not 4β‐phorbol, reduced the brief 45Ca efflux produced by AVP in the presence or in the absence of extracellular calcium. The maximal effect of TPA was to abolish the response to a half maximally active concentration of AVP, and to reduce by 50% the maximal response to the hormone. These results suggest that protein kinase C activation can exert a negative control on the early AVP‐induced calcium mobilization in vascular smooth muscle.
Presence of three pertussis toxin substrates and Goα immunoreactivity in both plasma and granule membranes of chromaffin cells
Authors: Toutant Madeleine , Aunis Dominique , Bockaert Joël , Homburger Vincent , Rouot Bruno
Published: July 2002

GTP‐binding proteins have been proposed to be involved in some secretory processes. Bordetella pertussis toxin is known to catalyze ADP‐ribosylation of several GTP‐binding proteins. In this paper, the subcellular localization of B. pertussis toxin substrates has been explored in chromaffin cells of bovine adrenal medulla. With appropriate gel electrophoresis conditions, three ADP‐ribosylated substrates of 39, 40 and 41 kDa were detectable in both plasma and granule membranes. The more intense labelling occurred on the 40 kDa component, while the 41 kDa species exhibited electrophoretic mobility similar to that of Giα. Significant immunoreactivity with anti‐Goα antibodies was detected at the level of the 39 kDa faster component. The association of G‐proteins with granule and plasma membranes suggests the involvement of these proteins in the exocytotic process or in its regulation.
α‐Bungarotoxin interacts with the rat brain tachykinin receptors
Authors: Utkin Yu.N. , Lazakovich E.M. , Kasheverov I.E. , Tsetlin V.I.
Published: July 2002

α‐Bungarotoxin (αBgt) was shown to inhibit the binding of the 125I‐labeled substance P (SP) and eledoisin (EL) to the rat brain membranes with K
1 values of 8.0±5.0 × 10−8 and 1.1±0.5 × 10−6 M, respectively. Lower inhibitory activity was manifested by several other postsynaptically acting snake venom neurotoxins. The αBgt inhibition of SP binding with a K
1 value of 8.5±5.5 × 10−8 M to solubilized preparations of the rat brain membranes was demonstrated. The capacity to displace SP was found for d‐tubocurarine and phencyclidine, although at concentrations considerably higher than those affecting the nicotinic acetylcholine receptors (AChRs). The results obtained suggest that some of the αBgt‐binding polypeptides, distinct from neuronal AChRs, may be functionally associated with the tachykinin receptors (TchR).
Expression of voltage‐gated K+ channels in insulin‐producing cells
Authors: Betsholtz Christer , Baumann Arnd , Kenna Susan , Ashcroft Frances M. , Ashcroft Stephen J.H. , Berggren Per-Olof , Grupe Andrew , Pongs Olaf , Rorsman Patrik , Sandblom John , Welsh Michael
Published: July 2002

We have used the polymerase chain reaction (PCR) with primers against the S5 and S6 regions of voltage‐gated K+ channels to identify 8 different specific amplification products using poly(A)+ RNA isolated from islets of Langerhans from obese hyperglycémic (ob/ob) mice and from the two insulin‐producing cell lines HIT T15 and RINmSF. Sequence analysis suggests that they derive from mRNAs coding for a family of voltage‐gated K+ channels; 5 of these have been recently identified in mammalian brain and 3 are novel. These hybridize in classes to different mRNAs which distribute differently to a number of tissues and cell lines including insulin‐producing cells.
A new protein inhibitor of trypsin and activated hageman factor from pumpkin (Cucurbita maxima) seeds
Authors: Krishnamoorthi Ramaswamy , Gong YuXi , Richardson Michael
Published: July 2002

A protein inhibitor (CMTI‐V; M
r 7106) of trypsin and activated Hageman factor (Factor XIIa), a serine protease involved in blood coagulation, has been isolated for the first time from pumpkin (Cucurbita maxima) seeds by means of trypsin‐affinity chromatography and reverse phase high performance liquid chromatography (HPLC). The dissociation constants of the inhibitor complexes with trypsin and Factor XIIa have been determined to be 1.6 × 10−8 and 4.1 × 10−8 M, respectively. The primary structure of CMTI‐V is reported. The protein has 68 amino acid residues and one disulfide bridge and shows a high level of sequence homology to the Potato I inhibitor family. Furthermore, its amino terminus consists of an N‐acetylates Ser. The reactive site has been established to be the peptide bond between Lys44‐Asp45. The modified inhibitor which has the reactive site peptide bond hydrolyzed inhibits trypsin but not the Hageman factor.
Three C‐phycoerythrin‐associated linker polypeptides in the phycobilisome of green‐light‐grown Calothrix sp. PCC 7601 (cyanobacteria)
Authors: Glauser Manuel , Sidler Walter A. , Graham Karl W. , Bryant Donald A. , Frank Gerhard , Wehrli Ernst , Zuber Herbert
Published: July 2002

Microanalyses by SDS‐PAGE and microsequencing demonstrate that, under green‐light conditions, 3 C‐phycoerythrin associated rod‐linker polypeptides with different N‐terminal amino acid sequences are present in phycobilisomes (PBS) from Calothrix sp. 7601 cells. Two of these polypeptides, corresponding to SDS‐PAGE bands at 36 and 37 kDa, could be assigned, respectively, to the cpeC and epeD genes found on a separate cpeCD‐operon in Calothrix sp. 7601 (Federspiel, N.A. and Grossman, A.R. (1990) J. Bacteriol. 172, 4072‐4081). The third C‐PE rod‐linker polypeptide, LR,2
PE,33, requires, therefore, a third gene with the suggested locus designation ‘cpeE’. A C‐PE (αβ)6‐LR,2
PE,33 complex containing this third rod‐linker polypeptide could be isolated from phycobilisomes and characterized. PBS from both green‐ and red‐light cells of Calothrix contain a single, unique LRC
28 rod‐core linker polypeptide which is not altered during chromatic adaptation.
Histone deacetylase
Authors: López-Rodas Gerardo , Brosch Gerald , Georgieva Elena I. , Sendra Ramón , Franco Luis , Loidl Peter
Published: July 2002

Core histones can be modified by reversible, posttranslational acetylation of specific lysine residues within the N‐terminal protein domains. The dynamic equilibrium of acetylation is maintained by two enzyme activities, histone acetyltransferase and histone deacetylase. Recent data on histone deacetylases and on anionic motifs in chromatin‐ or DNA‐binding regulatory proteins (e.g. transcription factors, nuclear proto‐oncogenes) are summarized and united into a hypothesis which attributes a key function to histone deacetylation for the binding of regulatory proteins to chromatin by a transient, specific local increase of the positive charge in the N‐terminal domains of nucleosomal core histones. According to our model, the rapid deacetylation of distinct lysines in especially H2A and H2B would facilitate the association of anionic protein domains of regulatory proteins to specific nucleosomes. Therefore histone deacetylation (histone deacetylases) may represent a unique regulatory mechanism in the early steps of gene activation, in contrast to the more structural role of histone acetylation (histone acetyltransferases) for nucleosomal transitions during the actual transcription process.
Identification and partial purification of a Bacillus thuringiensis CryIC δ‐endotoxin binding protein from spodoptera littoralis gut membranes
Authors: Sanchis Vincent , Ellar David J.
Published: July 2002

Immunoblotting experiments were performed using CryIC and CryIA(c) Bacillus thuringiensis δ‐endotoxins to detect the presence of specific toxin binding proteins on Spodoptera littoralis brush border membrane vesicles. The CryIC toxin binds two proteins of 40 and 65 kDa and the CryIA(c) binds a protein of 40 kDa. The CryIA(c) toxin also binds faintly to a 120 kDa protein on S. littoralis brush border membrane vesicles as does a polyclonal antiserum raised against a putative CryIA(c) 120 kDa binding protein from Manduca sexta. The 40 kDa CryIC binding protein was partially purified by affinity chromatography and is therefore a strong candidate for in vivo S. littoralis CryIC toxin receptor.
Forskolin stimulates porcine sperm capacitation by increasing calcium uptake
Authors: Okamura Naomichi , Tanba Michiko , Fukuda Atsunori , Sugita Yoshiki , Nagai Taku
Published: July 2002

Using the fluorescent calcium indicator fura‐2, forskolin was found to dose‐dependently cause an immediate increase in the concentration of intracellular free calcium of porcine cauda epididymal sperm. This stimulatory effect of forskolin is due to the enhancement of Ca2+ uptake by the verapamil‐sensitive transporter on the sperm plasma membrane and results in the promotion of the sperm capacitation and subsequent acrosome reaction.
Molecular cloning of a novel rat G‐protein‐coupled receptor gene expressed prominently in lung, adrenal, and liver
Authors: Harrison Jeffrey K. , Barber Cynthia M. , Lynch Kevin R.
Published: July 2002

A gene and cDNA (named G10d) encoding a novel member of the G‐protein‐coupled receptor (GCR) superfamily has been isolated from a rat genomic library and a rat liver cDNA library by tandom polymerase chain reaction (PCR) amplification and hybridization screening. Comparison of the sequence of the encoded protein to other members of the rhodopsin family of the GCR superfamily suggests that this new member is a peptide receptor. The G10d gene is present as a single copy in the rat genome and its translational open reading frame is intronless. Northern analysis demonstrates a wide and uneven distribution of G10d mRNA in the adult rat, with the highest mRNA abundance in lung, liver and adrenal gland extracts.
Association of N‐ethylmaleimide‐sensitive factor with synaptic vesicles
Authors: Hong Rong-Mao , Mori Hiroyuki , Fukui Toshio , Moriyama Yoshinori , Futai Masamitsu , Yamamoto Akitsugu , Tashiro Yutaka , Tagaya Mitsuo
Published: July 2002

N‐Ethylmaleimide‐sensitive factor (NSF) mediates docking and/or fusion of transport vesicles in the multi‐pathways of vesicular transport. NSF was highly expressed in brain and adrenal gland. Immunostaining of cerebellum with an anti‐NSF monoclonal antibody showed that NSF is predominantly localized in the molecular layers and the glomeruli of the granule cell layers. This distribution coincided well with that of synaptophysin, a marker protein of synaptic vesicles. Purification and immunoprecipitation revealed that NSF is associated with brain synaptic vesicles. The present results suggest that NSF is associated with synaptic vesicles without Ca2+ influx.
Transforming growth factor‐β1 downregulates dexamethasone‐indunced tetranectin gene expression during the in vitro mineralization of the human osteoblastic cell line SV‐HFO
Authors: Iba Kousuke , Sawada Norimasa , Chiba Hideki , Wewer Ulla M. , Ishii Seiichi , Mori Michio
Published: July 2002

In the present study, we examined the regulation of tetranectin gene expression using a human osteoblastic cell line, SV‐HFO, that undergoes mineralization upon treatment with dexamethasone. We found that the expression of tetranectin and alkaline phosphatase mRNA was induced by dexamethasone treatment as evidenced by Northern blotting. When transforming growth factor‐β
1 (TGF‐β
1) was added together wwith dexamethasone to the SV‐HFO cell cultures, the mineralization process was markedly suppressed and the expression of tetra nectin and alkaline phosphatase was downregulated in a dosedependent manner. These results demonstrate that the expression of tetranectin in these osteoblastic cells is regulated by dexamethasone and TGF‐β
1 and that tetranectin expression is tightly linked to the process of mineralization.
Expression of the gene for the receptor of gonadotropin‐releasing hormone in the rat mammary gland
Authors: Levi Linet Nur , Ben-Aroya Nurit , Tel-Or Shoshana , Palmon Aaron , Burstein Yigal , Koch Yitzhak
Published: July 2002

Recent findings have demonstrated that the GnRH gene is expressed in the mammary gland of pregnant and lactating rats but not of virgin rats. Indeed, significant concentrations of biologically active GnRH have been found in milk of human, cow, sheep and rat. We have, therefore, looked for expression of the GnRH receptor in the rat mammary gland. By reverse transcription (RT)‐PCR amplification, we have demonstrated the presence of GnRH receptor mRNA in mammary gland samples derived from virgin, pregnant and lactating rats. The GnRH receptor transcript cloned from the mammary gland was sequenced and found to have an identical coding region to the one cloned from the pituitary gland. In addition, we have found that the mammary gland, as the pituitary gland, contains at least two transcripts having the same coding region but different 5′ non‐coding regions. Binding studies, however, could demonstrate only low‐affinity binding sites. These results, therefore, suggest that the regulation of the GnRH receptor occurs posttranscriptionally rather than at the level of transcription.
Differential reactivities of the Arachis hypogaea (peanut) and Vicia villosa B4 lectins with human ovarian carcinoma cells, grown either in vitro or in vivo xenograft model
Authors: Avichezer Dody , Arnon Ruth
Published: July 2002

PNA and VVA B4 recognize the tumor‐associated T antigen and its immediate precursor Tn, respectively. We found that both lectins are highly reactive in vitro, with human ovarian carcinoma cell lines, but only VVA B4 bound significantly to breast and oral cancer cells. This binding is inhibited by specific monosaccharides. The lectin binding receptors were purified, revealing a glycoprotein of 32 kDa for PNA, and two glycoproteins of 35 and 38 kDa for VVA B4. In vivo localization of PNA was almost exclusive (except for the kidneys) to the ovarian tumor xenografts. VVA B4 showed wider tissue biodistribution being preferentially accumulated in the tumors and ovaries.
Time course of luciferyl adenylate synthesis in the firefly luciferase reaction
Authors: Dukhovich Alexey , Sillero Antonio , Günther Sillero Maria A
Published: July 2002

The time course of luciferyl adenylate formation in the reaction catalyzed by firefly luciferase (EC 1.13.12.7) has been followed. The properties of luciferyl adenylate, enzymatically or chemically synthesized, as substrate of luciferase, have been compared. The potential use of luciferyl adenylate for luciferase detection is here proposed.
Cesarean and postpartum hysterectomy
Authors: Chanrachakul B. , Chaturachinda K. , Phuapradit W. , Roungsipragarn R.
Published: July 2002

Objective: To review the cases of cesarean and postpartum hysterectomy. Method: A retrospective study of all cases of cesarean and postpartum hysterectomy during 1985–1994. Maternal characteristics, method of delivery, indications for hysterectomy and complications were reviewed. Results: The rate of cesarean and postpartum hysterectomy was 1:1667 deliveries. Half of these cases were delivered by cesarean section. The main indications for hysterectomy were massive bleeding due to uterine atony, abnormal placental adhesions or uterine rupture. Maternal morbidity was high and there was one maternal death. Conclusion: Cesarean and postpartum hysterectomy is a necessary life‐saving operation. Although maternal mortality is rare, morbidity remains high. Prevention of complications that give rise to hysterectomy and optimally timed surgery should decrease maternal morbidity and mortality.
THE NANOMELIC MUTATION IN THE AGGRECAN GENE IS EXPRESSED IN CHICK CHONDROCYTES AND NEURONS
Authors: Domowicz Miriam , Krueger Richard C. , Li Hao , Mangoura Dimitra , Vertel Barbara M. , Schwartz Nancy B.
Published: July 2002

We have established the presence of at least two large chondroitin sulfate proteoglycans in the developing chick brain, one that reacts exclusively with HNK‐1, a carbohydrate epitope found on several neural specific molecules, and one that reacts with S103L, a defined peptide epitope in the CS‐2 domain of the cartilage‐specific chondroitin sulfate proteoglycan (CSPG), aggrecan. In order to determine the relationships between the two distinct S103L‐reactive CSPGs from cartilage (chondrocytes) and brain (neurons), as well as among the three large CSPGs expressed in brain, S103L, HNK‐1 and versican, we studied the expression of these multiple proteoglycan species in the brain of nanomelic chicks. We have previously shown that homozygous embryos expressing the nanomelic phenotype exhibit a single point mutation in the aggrecan gene. In the present study, the S103L CSPG is not accumulated or synthesized by embryonic chick CNS tissue or E8CH neuronal cultures derived from nanomelic chick embryo cerebral hemispheres. In contrast, expression of both versican and the HNK‐1 CSPG was normal in the mutant embryo CNS. Pulse chase experiments demonstrated the presence of the 380 kDa precursor in normal neurons and the 300 kDa truncated precursor in nanomelic neurons. Northern blot analysis revealed normal‐sized mRNA but reduced levels of expression of the S103L CSPG message in nanomelic neurons, while expression of the versican message was comparable in normal and nanomelic neurons. Most conclusively, the point mutation previously identified in nanomelic cartilage mRNA was also identified in nanomelic brain mRNA. Together these results provide evidence that a single aggrecan gene is expressed in both cartilage and CNS tissue leading to the production of identical core proteins which then undergo differential and tissue‐specific post‐translation processing, resulting in the characteristic tissue‐specific proteoglycans. Furthermore, versican and the HNK‐1 CSPG, although structurally and chemically similar to the S103L CSPG, are the products of separate genes.
Structural significance of the acyl group at the C‐10 position and the A ring of the taxane core of paclitaxel for inducing nitric oxide and tumor necrosis factor production by murine macrophages
Authors: Kirikae Teruo , Ojima Iwao , Fuero-Oderda Cecilia , Lin Songnian , Kirikae Fumiko , Hashimoto Masahito , Nakano Masayasu
Published: July 2002

The antitumor agent, paclitaxel (Taxol®), mimics the actions of lipopolysaccharide (LPS) on murine macrophages (Mφ). Various synthetic analogs of paclitaxel were examined for their potencies to induce nitric oxide (NO) and tumor necrosis factor (TNF) production by murine peritoneal Mφ, and by human peripheral blood cells. The benzoyl group at C‐2, the hydroxy group at C‐7 and the acetyl group at C‐10 were found to be critically important sites to activate murine Mφ. Nor‐seco‐taxoid analogs lacking the A ring of the taxane core of paclitaxel were inactive, but inhibit paclitaxel‐ or LPS‐induced NO production. All the compounds tested did not induce TNF production by human blood cells.
Assignment of haem ligands and detection of electronic absorption bands of molybdenum in the di‐haem periplasmic nitrate reductase of Paracoccus pantotrophus
Authors: Butler Clive S. , Ferguson Stuart J. , Berks Ben C. , Thomson Andrew J. , Cheesman Myles R. , Richardson David J.
Published: July 2002

The periplasmic nitrate reductase (NAP) from Paracoccus pantotrophus is a soluble two‐subunit enzyme (NapAB) that binds two c‐type haems, a [4Fe–4S] cluster and a bis‐molybdopterin guanine dinucleotide cofactor that catalyses the reduction of nitrate to nitrite. In the present work the NapAB complex has been studied by magneto‐optical spectroscopy to probe co‐ordination of both the NapB haems and the NapA active site Mo. The absorption spectrum of the NapAB complex is dominated by features from the NapB c‐type cytochromes. Using a combination of electron paramagnetic resonance spectroscopy and magnetic circular dichroism it was demonstrated that both haems are low‐spin with bis‐histidine axial ligation. In addition, a window between 600 and 800 nm was identified in which weak absorption features that may arise from Mo could be detected. The low‐temperature MCD spectrum shows oppositely signed bands in this region (peak 648 nm, trough 714 nm) which have been assigned to S‐to‐Mo(V) charge transfer transitions.
Cellulysin from the plant parasitic fungus Trichoderma viride elicits volatile biosynthesis in higher plants via the octadecanoid signalling cascade
Authors: Piel Jörn , Atzorn Rainer , Gäbler Ralph , Kühnemann Frank , Boland Wilhelm
Published: July 2002

Cellulysin, a crude cellulase from the plant parasitic fungus Trichoderma viride, induces the biosynthesis of volatiles in higher plants (Nicotiana plumbaginifolia, Phaseolus lunatus, and Zea mays) when applied to cut petioles by the transpiration stream. The pattern of the emitted volatiles largely resembles that from a herbivore damage or treatment of the plants with jasmonic acid (JA) indicating that cellulysin acts via activation of the octadecanoid signalling pathway. The treatment with cellulysin raises the level of endogenous JA after 30 min and is followed by a transient emission of ethylene after 2–3 h. Volatile production becomes significant after 12–24 h. Inhibitors of the JA pathway effectively block the cellulysin‐dependent volatile biosynthesis.
Sequence‐specific recognition of peptide substrates by the low Mr phosphotyrosine protein phosphatase isoforms
Authors: Bucciantini Monica , Stefani Massimo , Taddei Niccolò , Chiti Fabrizio , Rigacci Stefania , Ramponi Giampietro
Published: July 2002

A number of phosphotyrosine‐containing peptides derived from the PDGF receptor phosphorylation sites have been synthesised. The peptides were assayed as substrates of the two isoforms (IF1 and IF2) of the low M
r PTPase. The calculated k
cat, K
m, and k
cat/K
m values indicate that only one peptide is best hydrolysed by IF2 (but not IF1), whose catalytic efficiency averages those previously reported for most PTPases (except the Yersinia enzyme). This peptide is the only one containing a couple of no bulky hydrophobic residues at the phosphotyrosine N‐side. The determination of the same catalytic parameters in the presence of analogues of the best hydrolysed peptide in which one or both hydrophobic residues were replaced by Asp or Lys residues confirmed the importance of the hydrophobic cluster at the phosphotyrosine N‐side for optimal enzymatic hydrolysis. These findings are discussed in the light of the known IF2 X‐ray structure.
Impact of the lysine‐188 and aspartic acid‐189 inversion on activity of trypsin
Authors: Briand Loı̈c , Chobert Jean-Marc , Gantier René , Declerck Nathalie , Tran Vinh , Léonil Joëlle , Mollé Daniel , Haertlé Thomas
Published: July 2002

The impact of the charge rearrangement on the specificity of trypsin was tested by an inversion of sequence K188D/D189K maintaining the integrity of the charges of the substrate binding pocket when switching their polarity. In native trypsin, aspartate 189 situated at the bottom of the primary substrate binding pocket interacts with arginine and lysine side chains of the substrate. The kinetic parameters of the wild‐type trypsin and K188D/D189K mutant were determined with synthetic tetrapeptide substrates. Compared with trypsin, the mutant K188D/D189K exhibits a 1.5‐ to 6‐fold increase in the K
m for the substrates containing arginine and lysine, respectively. This mutant shows a ∼30‐fold decrease of its k
cat and its second‐order rate constant k
cat/K
m decreases ∼40‐ and 150‐fold for substrates containing arginine and lysine, respectively. Hence, trypsin K188D/D189K displays a large increase in preference for arginine over lysine.
Holding up a mirror: changing obstetric practice through criterion‐based clinical audit in developing countries
Authors: Wagaarachchi P.T. , Graham W.J. , Penney G.C. , McCaw‐Binns A. , Yeboah Antwi K. , Hall M.H.
Published: July 2002

The objective of the study described is to assess the feasibility and effectiveness of using a criterion‐based clinical audit to measure and improve the quality of obstetric care at the district hospital level in developing countries. The focus is on the management of five life‐threatening obstetric complications — hemorrhage, eclampsia, genital tract infection, obstructed labor and uterine rupture was audited using a ‘before and after’ design. The five steps of the audit cycle were followed: establish criteria of good quality care; measure current practice (Review I); feedback findings and set targets; take action to change practice; and re‐evaluate practice (Review II). Systematic literature review, panel discussions and pilot work led to the development of 31 audit criteria. Review I included 555 life‐threatening complications occurring over 66 hospital‐months; Review II included 342 complications over 42 hospital‐months. Many common areas for improvement were identified across the four hospitals. Agreed mechanisms for achieving these improvements included clinical protocols, reviews of staffing, and training workshops. Some aspects of clinical monitoring, drug use and record keeping improved significantly between Reviews I and II. Criterion‐based clinical audit in four typical district hospitals in Ghana and Jamaica is a feasible and acceptable method for quality assurance and appears to have improved the management of life‐threatening obstetric complications.
Maternal and fetal outcomes in hyperemesis gravidarum
Authors: Tsang I.S. , Katz V.L. , Wells S.D.
Published: July 2002

Objective: This study sought to evaluate maternal characteristics and pregnancy outcomes among women with hyperemesis gravidarum. Methods: We performed a retrospective analysis of pregnancy records of obstetric admissions during a 6‐year period. Women treated as out‐patients for hyperemesis were also identified. Hyperemesis was defined as excessive nausea and vomiting resulting in dehydration, extensive medical therapy, and/or hospital admission. Statistical analysis was by t‐test and chi square. Results: We identified 193 women (1.5%) who developed hyperemesis among 13053 women. Racial status, marital status, age, and gravidity were similar between the hyperemesis patients and the general population. However, there were less women with hyperemesis who were para 3 or greater. Forty‐six women (24%) required hospitalization for hyperemesis, mean hospital stay 1.8 days, range 1–10 days. One patient required parenteral nutrition, two had yeast esophagitis, none had HIV infection, psychiatric pathology or thyroid disease. Pregnancy outcomes between hyperemesis patients and the general population were similar for mean birth weight, mean gestational age, deliveries less than 37 weeks, Apgar scores, perinatal mortality or incidence of fetal anomalies. Our incidence of hyperemesis (1.5%) is similar to that of other published reports. Conclusion: Women with hyperemesis have similar demographic characteristics to the general obstetric population, and have similar obstetric outcomes.
Intraoperative blood salvage in abdominal simple total hysterectomy for uterine myoma
Authors: Yamada T , Ikeda A , Okamoto Yu , Okamoto Yo , Kanda T , Ueki M
Published: July 2002

Objective: To investigate the safety and usefulness of salvage‐type autologous blood transfusion for abdominal simple total hysterectomy for uterine myoma. Methods: Forty patients with uterine myoma diagnosed histologically were treated by abdominal simple total hysterectomy using an intraoperative blood salvage apparatus. Bacterial contamination in the processed blood was studied. Results: Homologous blood transfusion was unnecessary. There was a positive relationship between bleeding volume and the hemoglobin (g) level in the processed blood. All vaginal swabs were positive for bacteria. Bacterial cultures of all processed blood samples without an antibiotic were positive whereas results were negative in 11 (50%) of the processed blood samples with an antibiotic. There were no significant side effects after reinfusion. Conclusion: Salvage‐type autologous blood transfusion in abdominal simple total hysterectomy for uterine myoma was safe and its future use is promising.
Chronic low‐dose maternal exposure to methylmercury enhances epileptogenicity in developing rats
Authors: Szász A. , Barna B. , Szupera Z. , De Visscher G. , Galbács Z. , Kirsch‐Volders M. , Szente M.
Published: July 2002

Effects of continuous low‐dose maternal methylmercury intoxication on the induction and propagation of ictal epileptiform activity induced by 3‐aminopyridine, were investigated on the neocortex of 4‐weeks‐old offspring rats. Epileptogenicity was significantly increased in offspring of mercury‐treated animals compared to those of controls, characterized by more frequent occurrence of periodic ictal activity, a facilitated propagation of epileptiform discharges and a strong tendency to generalization. The latency of first ictal event was slightly shorter and the average duration of individual ictal periods slightly longer in treated animals. However, the amplitude of seizure discharges was significantly smaller in treated animals than in controls.

We conclude, that the synaptic and membrane mechanisms responsible for initiation and propagation of paroxysmal activity were probably facilitated, while the efficacy of cortical inhibition, in preventing initiation and spread of epileptiform discharges was reduced by mercury treatment in the developing nervous system. The smaller amplitude of paroxysmal discharges could be a sign of a remarkable loss of cortical neurons.
Hierarchical arrangement of psychiatric symptoms in the context of schizophrenia
Authors: Angelopoulos N.V. , Economou M.
Published: July 2002

Foulds’ model proposing a four-class hierarchical structure of mental illness represents an interesting dimension of psychiatric research and discussion and probably has a significant potential on diagnosis, taxonomy, therapeutics and theory. Psychiatric symptoms were investigated in a group of 244 schizophrenic patients with the purpose of analyzing Foulds and Bedford’s notion that psychiatric symptoms are arranged hierarchically. To achieve this the R (recent) version of the Delusions, Symptoms, States, Inventory (DSSI) was administered in the form of a constructed interview to these patients. The hierarchical arrangement of psychiatric symptoms was verified since a great majority of the cases (80.8%) produced symptom patterns conforming to the hierarchy model. However, patients with duration of illness longer than 10 years reported conforming patterns in a lower percentage (77%), whereas 84.6% of those with a duration of illness less than 2 years reported conforming patterns. The non-conforming patterns were those in which integrated delusions were absent in the presence of delusions of disintegration, neurotic symptoms were absent in the presence of integrated delusions, and dysthymic states were absent in the presence of neurotic symptoms.
Technical Note: Extended field‐of‐view (FOV) MRI distortion determination through multi‐positional phantom imaging
Authors: Schüler Emil , Mallozzi Richard , Levy Joshua , Hristov Dimitre
Published: October 2020

Comprehensive characterization of geometric distortions for MRI simulators and MRI‐guided treatment delivery systems is typically performed with large phantoms that are costly and unwieldy to handle. Here we propose an easily implementable methodology for MR distortion determination of the entire imaging space of the scanner through the use of a compact commercially available distortion phantom. The MagphanRT phantom was scanned at several locations within a MR scanner. From each scan, an approximate location of the phantom was determined from a subset of the fiducial spheres. The fiducial displacements were determined, and a displacement field was fitted to the displacement data using the entire multi‐scan data set. An orthogonal polynomial expansion fitting function was used that had been augmented to include independent rigid‐body transformations for each scan. The rigid‐body portions of the displacement field were thereafter discarded, and the resultant fit then represented the distortion field. Multi‐positional scans of the phantom were used successfully to determine the distortion field with extended coverage. A single scan of the phantom covered 20 cm in its smallest dimension. By stitching together overlapping scans we extended the distortion measurements to 30 cm. No information about the absolute location or orientation of each scan was required. The method, termed the Multi‐Scan Expansion (MSE) method, can be easily applied for larger field‐of‐views (FOVs) by using a combination of larger phantom displacements and more scans. The implementation of the MSE method allows for distortion determination beyond the physical limitations of the phantom. The method is scalable to the user’s needs and does not require any specialized equipment. This approach could open up for easier determination of the distortion magnitude at distances further from the scanner’s isocenter. This is especially important in the newly proposed methodologies of MR‐only simulation in RT and in adaptive replanning in MR linac systems.
Individual differences in face and voice matching abilities: The relationship between accuracy and consistency
Authors: Kramer Robin S. S. , Jones Alex L. , Gous Georgina
Published: October 2020

Deciding whether two different face photographs or voice samples are from the same person represent fundamental challenges within applied settings. To date, most research has focussed on average performance in these tests, failing to consider individual differences and within‐person consistency in responses. Here, participants completed the same face (Experiment 1) or voice matching test (Experiment 2) on two separate occasions, allowing comparison of overall accuracy across the two timepoints as well as consistency in trial‐level responses. In both experiments, participants were highly consistent in their performances. In addition, we demonstrated a large association between consistency and accuracy, with the most accurate participants also tending to be the most consistent. This is an important result for applied settings in which organisational groups of super‐matchers are deployed in real‐world contexts. Being able to reliably identify these high performers based upon only a single test informs regarding recruitment for law enforcement agencies worldwide.
Area‐Selective Growth of HfS2 Thin Films via Atomic Layer Deposition at Low Temperature
Authors: Cao Yuanyuan , Wähler Tobias , Park Hyoungwon , Will Johannes , Prihoda Annemarie , Moses Badlyan Narine , Fromm Lukas , Yokosawa Tadahiro , Wang Bingzhe , Guldi Dirk M. , Görling Andreas , Maultzsch Janina , Unruh Tobias , Spiecker Erdmann , Halik Marcus , Libuda Jörg , Bachmann Julien
Published: October 2020

The transition‐metal dichalcogenide HfS2 is a promising alternative semiconductor with adequate band gap and high carrier mobility. However, a controllable growth of continuous HfS2 films with selectivity for specific surfaces at a low temperature on a large scale has not been demonstrated yet. Herein, HfS2 films are grown at 100 °C by atomic layer deposition (ALD) based on the precursors tetrakis(dimethylamido)hafnium and H2S. In situ vibrational spectroscopy allows for the definition of the temperature range over which (Me2N)4Hf chemisorbs as one monolayer. In that range, sequential exposures of the solid surface with (Me2N)4Hf and H2S result in self‐limiting reactions that yield alternating surface termination with dimethylamide and thiol. Repeating the cycle grows smooth, continuous, stoichiometric films of thicknesses adjustable from angstroms to >100 nm, as demonstrated by spectroscopic ellipsometry, XRR, AFM, UV–vis and Raman spectroscopy, XPS, and TEM. The well‐defined surface chemistry enables one to deposit HfS2 selectively using, for example, patterns generated in molecular self‐assembled monolayers. This novel ALD reaction combines several attractive features necessary for integrating HfS2 into devices.
Soil‐test biological activity with short‐term and long‐term carbon contributions
Authors: Franzluebbers Alan J. , Assmann Tangriani S.
Published: October 2020

Soil‐test biological activity (STBA) is a key indicator of soil health because of its relevance to ecosystem processing, broad applicability, and simple and rapid analysis. Short‐term and long‐term influences of carbon (C) availability on STBA were assessed. A short‐term factor was root‐derived C inputs from a sudangrass (Sorghum × drummondii) test crop grown under greenhouse conditions. Long‐term factors were from soil at two depths in three sections of a field varying in soil texture and exposed to 16 yr of different pasture–crop rotation management. Soil‐test biological activity was determined after 0, 14, 21, 31, and 45 d of greenhouse growth. Total variation in STBA was 7% from the short‐term factor and 81% from the long‐term factors. Soil depth was the primary long‐term factor influencing STBA (57%) and soil texture was intermediate (24%). Results indicate that short‐term changes in STBA are important but modest compared with variations due to soil depth and texture.
pH‐Responsive Torpedo‐Like Persistent Luminescence Nanoparticles for Autofluorescence‐Free Biosensing and High‐Level Information Encryption
Authors: Li Juan , Huang Xiaolin , Zhao Xu , Chen Li‐Jian , Yan Xiu‐Ping
Published: October 2020

Persistent luminescent nanoparticles (PLNPs) with intrinsic stimuli‐responsive properties are desirable because of no autofluorescence background and natural responsive luminescence. However, the stimuli‐responsive features of pure PLNPs have been unexplored. Here we show a facile one‐pot hydrothermal synthesis of green‐emitting Zn2GeO4:Mn2+,Pr3+ nanoparticles (ZGMP) with regular shape, uniform size and good afterglow luminescent performance. We also report the pH stimuli‐responsive luminescent behavior of ZGMP and its possible mechanism. Taking the intriguing feature of pH responsive persistent luminescence, we explore ZGMP as autofluorescence‐free probes to achieve stimuli‐activated signal switch for biosensing by integrating enzyme catalysis reaction mediated pH modulation. The pH‐responsive persistent luminescence also makes ZGMP promising for high‐level information encryption.
Design, synthesis, molecular docking, anticancer evaluations, and in silico pharmacokinetic studies of novel 5‐[(4‐chloro/2,4‐dichloro)benzylidene]thiazolidine‐2,4‐dione derivatives as VEGFR‐2 inhibitors
Authors: El‐Adl Khaled , El‐Helby Abdel‐Ghany A. , Sakr Helmy , Ayyad Rezk R. , Mahdy Hazem A. , Nasser Mohamed , Abulkhair Hamada S. , El‐Hddad Sanadelaslam S. A.
Published: October 2020

The anticancer activity of novel thiazolidine‐2,4‐diones was evaluated against HepG2, HCT‐116, and MCF‐7 cells. MCF‐7 was the most sensitive cell line to the cytotoxicity of the new derivatives. In particular, compounds 18, 12, 17, and 16 were found to be the most potent derivatives over all the tested compounds against the cancer cell lines HepG2, HCT116, and MCF‐7, with IC50 = 9.16 ± 0.9, 8.98 ± 0.7, 5.49 ± 0.5 µM; 9.19 ± 0.5, 8.40 ± 0.7, 6.10 ± 0.4 µM; 10.78 ± 1.2, 8.87 ± 1.5, 7.08 ± 1.6 µM; and 10.87 ± 0.8, 9.05 ± 0.7, 7.32 ± 0.4 µM, respectively. Compounds 18 and 12 have nearly the same activities as sorafenib (IC50 = 9.18 ± 0.6, 5.47 ± 0.3, and 7.26 ± 0.3 µM, respectively), against HepG2 cells, but slightly lower activity against HCT116 cells and slightly higher activity against the MCF‐7 cancer cell line. Also, these compounds displayed lower activities than doxorubicin against HepG2 and HCT‐116 cells but higher activity against MCF‐7 cells (IC50 = 7.94 ± 0.6, 8.07 ± 0.8, and 6.75 ± 0.4 µM, respectively). In contrast, compounds 17 and 16 exhibited lower activities than sorafenib against HepG2 and HCT116 cells, but nearly equipotent activity against the MCF‐7 cancer cell line. Also, these compounds displayed lower activities than doxorubicin against the three cell lines. All the synthesized derivatives 7–18 were evaluated for their inhibitory activities against VEGFR‐2. The tested compounds displayed high to medium inhibitory activity, with IC50 values ranging from 0.17 ± 0.02 to 0.27 ± 0.03 µM. Compounds 18, 12, 17, and 16 potently inhibited VEGFR‐2 at IC50 values of 0.17 ± 0.02, 0.17 ± 0.02, 0.18 ± 0.02, and 0.18 ± 0.02 µM, respectively, which are nearly more than half of that of the IC50 value for sorafenib (0.10 ± 0.02 µM).
Resource allocation explains lactic acid production in mixed‐culture anaerobic fermentations
Authors: Regueira Alberte , Rombouts Julius. L. , Wahl S. Aljoscha , Mauricio‐Iglesias Miguel , Lema Juan M. , Kleerebezem Robbert
Published: October 2020

Lactate production in anaerobic carbohydrate fermentations with mixed cultures of microorganisms is generally observed only in very specific conditions: the reactor should be run discontinuously and peptides and B vitamins must be present in the culture medium as lactic acid bacteria (LAB) are typically auxotrophic for amino acids. State‐of‐the‐art anaerobic fermentation models assume that microorganisms optimise the adenosine triphosphate (ATP) yield on substrate and therefore they do not predict the less ATP efficient lactate production, which limits their application for designing lactate production in mixed‐culture fermentations. In this study, a metabolic model taking into account cellular resource allocation and limitation is proposed to predict and analyse under which conditions lactate production from glucose can be beneficial for microorganisms. The model uses a flux balances analysis approach incorporating additional constraints from the resource allocation theory and simulates glucose fermentation in a continuous reactor. This approach predicts lactate production is predicted at high dilution rates, provided that amino acids are in the culture medium. In minimal medium and lower dilution rates, mostly butyrate and no lactate is predicted. Auxotrophy for amino acids of LAB is identified to provide a competitive advantage in rich media because less resources need to be allocated for anabolic machinery and higher specific growth rates can be achieved. The Matlab™ codes required for performing the simulations presented in this study are available at https://doi.org/10.5281/zenodo.4031144.
Teaching concepts related to finite automata using ComVis
Authors: Jovanović Nenad , Miljković Dragiša , Stamenković Srećko , Jovanović Zoran , Chakraborty Pinaki
Published: October 2020

This paper describes educational software for visualization and finite automata simulation. The system was developed in Java programming language, and its main purpose is learning process improvement. Using this software, finite automata can be defined in a graphical editor in the form of a state diagram, or by defining the transition function using the transition table. Upon defining an automaton, it is possible to run a visual simulation of the automaton operation for an arbitrary input string, whereby a textual description of the automaton simulation is also obtained. Furthermore, the system allows for conversion of regular expressions to deterministic finite automata and nondeterministic finite automata. The simulation of Thompson's construction algorithm is implemented, so that transformation of a regular expression to the corresponding NFA can be monitored in a step‐by‐step process. The quantitative analysis and evaluation of the effectiveness of the simulator are based on a survey of undergraduate students at two universities. The majority of students found the tool a useful means for better understanding and mastering of finite automata concepts.
Renal Thrombotique microangiopathy: An unusual renal involvement in Niemann‐Pick disease type B
Authors: Jerbi Mouna , Sayhi Mariem , Gaied Hanene , Hedri Hafedh , Aoudia Raja , Goucha Rim , Abdallah Taieb Ben
Published: October 2020

Renal involvement in Niemann‐Pick disease type B is very rare. Kidney check‐up and renal biopsy should be performed in any patient presented with hypertension and kidney disease. Histology identifies the lesion, the prognosis, and guide treatment.
Dynamic Helicates Self‐Assembly from Homo‐ and Heterotopic Dynamic Covalent Ligand Strands
Authors: Santoro Antonio , Holub Jan , Fik‐Jaskółka Marta A. , Vantomme Ghislaine , Lehn Jean‐Marie
Published: October 2020

The understanding and the application of reversible covalent reactions and coordination chemistry together with the proper design of the molecular frameworks, allow to achieve not only well‐defined output architectures but also different grades of complex behavior. In this work, the dynamic nature of the helical systems offers an additional level of complexity by combining self‐sorting on two levels: 1) the build‐up of the ligand strand constituents from their components through dynamic covalent chemistry; 2) the assembly of the helicates from the ligands and the metal cations through dynamic metallo‐supramolecular chemistry. The information encoded in the ligands constituent molecule was read differently (and accurately at the same time) by metal cations that varied in the coordination algorithms. It enabled the selective formation of a specific type of helicates from a wide library of helicates formed by the possible combination of subcomponents. Ligands containing dynamic tridentate and/or bidentate binding motifs in the same strand were studied to explore the helicates self‐assembly with appropriate metal cations.