bluuebunny/crossref_metadata_2025 huggingface dataset:
Musculoskeletal symptoms and presentism among professionals of public health management of Belem-PA, Brazil
Authors: Moraes William Rafael Almeida , Neves Laura Maria Tomazi , Alcântara Rita Cristina Cotta
Published: July 2021

Introduction: Work-related musculoskeletal disorders affect the performance of workers and can increase presenteeism, a condition in which the employee comes to the workplace but does not produce satisfactory results because he is ill. Objective: To identify the prevalence of musculoskeletal symptoms and its association with presenteeism among public health management professionals of Belem-PA, Brazil. Methods: Cross-sectional study carried out with 88 professionals from the Municipal Health Department of Belem. A sociodemographic questionnaire was used to characterize the sample; the Nordic Musculoskeletal Questionnaire to identify the prevalence of pain, numbness, and tingling symptoms in the body; and the Stanford Presenteeism Scale to characterize presenteeism. Associations between variables were analyzed using a 5% significance level. Results: Musculoskeletal symptoms in the upper and lower back were the most prevalent. Presenteeism was significantly associated with daily workload, physical activity, and the presence of diagnosed musculoskeletal diseases or injuries. In the past 12 months, musculoskeletal symptoms in the neck, upper and lower back, wrists/hands, and hips/thighs have been associated with presenteeism. In the past 7 days, presenteeism has been associated with symptoms in the upper back and lower back. Conclusion: The most prevalent musculoskeletal disorders in health management professionals are associated with presenteeism.
Recommendations for specimen collection for detection and diagnosis of COVID-19
Authors: Dall'Agnol Juliana , Schwartz Eda , Lise Fernanda
Published: July 2021

Introduction: The spread of SARS-CoV-2 has caused a global public health crisis (pandemic). One of the most important measures to control the transmission chain of the new coronavirus is to identify those infected through laboratory testing. Objective: Synthesize the recommendations for the specimen collection for detection and diagnosis of COVID-19. Methods: This is an integrative review, considering the publications of the following databases: PubMed and Google Academic from January 2020. Results: 468 publications were identified, 20 of which were considered eligible. The publications recommend that technical training for specimen collection and careful observation of infection prevention protocols are fundamental. This manuscript highlights the steps for specimen collection as materials for collection, storage, transportation, individual protection, and laboratory analysis of samples. Currently, the Reverse Transcription - Polymerase Chain Reaction test is the recommended and gold standard method of identifying COVID-19 cases. Serological tests play an important role in research and surveillance. Conclusion: In summary, the documents ensure that the RT-PCR is the gold standard for SARS-CoV-2 detection and recommend standardization of collection and conditioning methods to avoid errors related to the collection and false negative results.
Laughing with machines
Authors: Hietalahti Jarno
Published: July 2021

This article will analyse the preconditions of sense of humour for artificial intelligence. Can artificial intelligence have a sense of humour? Is there a difference between human and machine laughter? Some machines already fulfil certain conditions which are associated with the human sense of humour: on the most superficial level machines appear to laugh and produce jokes, and they recognize sarcasm and punchlines, and they can evaluate funniness. In short, artificial intelligence is already able to recognize humour, and reacts to it accordingly. Furthermore, people laugh with humorous machines. However, it is still uncertain whether artificial intelligence can have a sense of humour or not, at least in comparison to a human sense of humour. To build bridges between AI research and philosophy of humour, this article proposes that there are (at least) five notable philosophical issues to be addressed if we are to accept that machines can have a (humanlike) sense of humour. These principles are: 1) worldview, 2) self-consciousness, 3) self-reflection, 4) self-criticism, and 5) losing control.
Laughter in the context of urban soundscapes
Authors: Vasileva Daria
Published: July 2021

Fifty people compiled diaries in which they described the sounds of their daily life in cities around the world. Of the 940 hours of observation there were 200 entries that referred to sounds of laughter, both live and recorded. The participants of the research always identified laughter sounds explicitly, unlike other urban sounds. The sound of laughter has a powerful cultural-symbolic superstructure. Learning how we use laughter, what we hear and how we react when someone laughs can help us to understand the key processes taking place in the urban space today. Laughter can at once attract and repel, signal danger and relieve social tension. It can lead equally to social agents’ inclusion and exclusion in the situation of interaction, and can largely determine the form and extent of their inclusion. A citizen’s interpretation of the sound of laughter depends directly on the media technologies which predominate in the urban environment and channel their cultural experience and sonic imagination.
Natural language understanding of map navigation queries in Roman Urdu by joint entity and intent determination
Authors: Hassan Javeria , Tahir Muhammad Ali , Ali Adnan
Published: July 2021

Navigation based task-oriented dialogue systems provide users with a natural way of communicating with maps and navigation software. Natural language understanding (NLU) is the first step for a task-oriented dialogue system. It extracts the important entities (slot tagging) from the user’s utterance and determines the user’s objective (intent determination). Word embeddings are the distributed representations of the input sentence, and encompass the sentence’s semantic and syntactic representations. We created the word embeddings using different methods like FastText, ELMO, BERT and XLNET; and studied their effect on the natural language understanding output. Experiments are performed on the Roman Urdu navigation utterances dataset. The results show that for the intent determination task XLNET based word embeddings outperform other methods; while for the task of slot tagging FastText and XLNET based word embeddings have much better accuracy in comparison to other approaches.
The effects of genetic drift and genomic selection on differentiation and local adaptation of the introduced populations of Aedes albopictus in southern Russia
Authors: Konorov Evgenii A. , Yurchenko Vyacheslav , Patraman Ivan , Lukashev Alexander , Oyun Nadezhda
Published: July 2021

Background

Asian tiger mosquito Aedes albopictus is an arbovirus vector that has spread from its native habitation areal in Southeast Asia throughout North and South Americas, Europe, and Africa. Ae. albopictus was first detected in the Southern Federal District of the Russian Federation in the subtropical town of Sochi in 2011. In subsequent years, this species has been described in the continental areas with more severe climate and lower winter temperatures.

Methods

Genomic analysis of pooled Ae. albopictus samples collected in the mosquito populations in the coastal and continental regions of the Krasnodar Krai was conducted to look for the genetic changes associated with the spread and potential cold adaptation in Ae. albopictus.

Results

The results of the phylogenetic analysis based on mitochondrial genomes corresponded well with the hypothesis that Ae. albopictus haplotype A1a2a1 was introduced into the region from a single source. Population analysis revealed the role of dispersal and genetic drift in the local adaptation of the Asian tiger mosquito. The absence of shared haplotypes between the samples and high fixation indices suggest that gene flow between samples was heavily restricted. Mitochondrial and genomic differentiation together with different distances between dispersal routes, natural and anthropogenic barriers and local effective population size reduction could lead to difficulties in local climatic adaptations due to reduced selection effectiveness. We have found genomic regions with selective sweep patterns which can be considered as having been affected by recent selection events. The genes located in these regions participate in neural protection, lipid conservation, and cuticle formation during diapause. These processes were shown to be important for cold adaptation in the previous transcriptomic and proteomic studies. However, the population history and relatively low coverage obtained in the present article could have negatively affect sweep detection.
Dose-response relationship among body mass index, abdominal adiposity and atrial fibrillation in patients undergoing cardiac surgery: a meta-analysis of 35 cohorts
Authors: Liu Menglu , Mei Kaibo , Xie Lixia , Ma Jianyong , Yu Peng , Niu Siquan , Xu Ya , Zhao Yujie , Liu Xiao
Published: July 2021

Background

Whether overweight increases the risk of postoperative atrial fibrillation (POAF) is unclear, and whether adiposity independently contributes to POAF has not been comprehensively studied. Thus, we conducted a meta-analysis to clarify the strength and shape of the exposure-effect relationship between adiposity and POAF.

Methods

The PubMed, Cochrane Library, and EMBASE databases were searched for revelant studies (randomized controlled trials (RCTs), cohort studies, and nest-case control studies) reporting data regarding the relationship between adiposity and the risk of POAF.

Results

Thirty-five publications involving 33,271 cases/141,442 patients were included. Analysis of categorical variables showed that obesity (RR: 1.39, 95% CI [1.21–1.61]; P < 0.001), but not being underweight (RR: 1.44, 95% CI [0.90–2.30]; P = 0.13) or being overweight (RR: 1.03, 95% CI [0.95–1.11]; P = 0.48) was associated with an increased risk of POAF. In the exposure-effect analysis (BMI) was 1.09 (95% CI [1.05–1.12]; P < 0.001) for the risk of POAF. There was a significant linear relationship between BMI and POAF (Pnonlinearity = 0.44); the curve was flat and began to rise steeply at a BMI of approximately 30. Notably, BMI levels below 30 (overweight) were not associated with a higher risk of POAF. Additionally, waist obesity or visceral adiposity index was associated with the risk of POAF.

Conclusion

Based on the current evidence, our findings showed that high body mass index or abdominal adiposity was independently associated with an increased risk of POAF, while underweight or overweight might not significantly increase the POAF risk.
In vivo glucose activation of the yeast plasma membrane ATPase
Authors: Serrano Ramón
Published: July 2002

The addition of glucose to yeast cells activates proton efflux mediated by the plasma membrane ATPase. Accordingly, the ATPase activity of purified plasma membranes is increased up to 10‐fold. The activated ATPase has a more alkaline pH optimum, better affinity for ATP and greater sensitivity to vanadate than the non‐activated enzyme. All these changes are reversed by washing the cells free of glucose. This suggests two states of the ATPase which are interconverted by a covalent modification. As glucose does not affect the phosphorylation of plasma membrane polypeptides, other type of covalent modification may be involved.
The functional domain of hirudin, a thrombin‐specific inhibitor
Authors: Chang Jui-Yoa
Published: July 2002

Hirudin is a thrombin‐specific of M
r 8000 (65 amino acid residues). Native hirudin contains 3 disulfide linkages within the first 39 amino‐terminal residues, and highly C‐terminal segment which is freely accessible to enzyme digestion by both endo‐ and exo‐peptidases. Removal of the acidic C‐terminal amino acids of native hirudin by both chemical and enzymatic methods resulted in a concomitant loss of hirudin inhibition activity. It is concluded that this acidic C‐terminal segment of hirudin is essential for hirudin—thrombin interaction. The implication of the hirudin—thrombin interaction for the enzymatic specificity of thrombin is also discussed.
Isocitrate dehydrogenase of the thermoacidophilic archaebacterium Sulpholobus acidocaldarius
Authors: Danson Michael J. , Wood Pauline A.
Published: July 2002

The thermoacidophilic archaebacterium, Sulpholobus acidocaldarius has been found to possess both NAD‐ and NADP‐dependent isocitrate dehydrogenase activities. Evidence is presented to suggest that both enzymic activities are functions of the same protein: NAD+ and NADP+ compete with each other for the enzyme and do so with K
i values equal to their K
m values; thermal inactivation results in the loss of both activities at the same rate and copurification was observed on gel filtration, ion‐exchange chromatography and polyacrylamide gel electrophoresis. The evolutionary significance of this unique isocitrate dehydrogenase is discussed.
4‐Hydroxyalk‐2‐enals are substrates for glutathione transferase
Authors: Ålin Per , Danielson U.Helena , Mannervik Bengt
Published: July 2002

The 4‐hydroxyalk‐2‐enals are established products of lipid peroxidation that are conjugated with intracellular glutathione. Cytosolic glutathione transferases from rat liver were shown to give high specific activities with 4‐hydroxynonenal and 4‐hydroxydecenal. The isoenzyme giving the highest specific activity was glutathione transferase 4‐4. The rate of the spontaneous conjugation reaction is negligible in comparison with the rate calculated for the cellular concentration of the glutathione transferases. It is proposed that a major biological function of the glutathione transferases is to protect the cell against products of oxidative metabolism, such as epoxides, organic hydroperoxides, and 4‐hydroxyalkenals.
NADPH‐dependent generation of H2O2 in a thyroid particulate fraction requires Ca2+
Authors: Deme Danielle , Virion Alain , Hammou Néfissa Ait , Pommier Jacques
Published: July 2002

The action of Ca2+ on H2O2 formation catalyzed by an NADPH‐dependent H2O2‐generating system was studied in a thyroid particulate fraction. It was shown that H2O2 formation was inhibited by EGTA and restored in the presence of micromolar concentrations of free Ca2+, and that Mg2+ was unable to restore the activity of the EGTA‐inhibited particulate fraction. Consequently, NADPH‐dependent H2O2 formation requires Ca2+, and the Ca2+ stimulation of this process is specific and reversible.
Spectral properties of fluorescent flavoproteins of isolated rat liver mitochondria
Authors: Kunz Wolfram S.
Published: July 2002

The different flavoproteins contributing to flavin fluorescence of isolated rat liver mitochondria have distinct excitation and emission spectra. The NAD‐linked flavin component was identified as α‐lipoamide dehydrogenase, while the non‐NAD‐linked component was found to be electron transfer flavoprotein. The differences in excitation and emission properties of the mitochondrial flavoproteins permit selective recording of their redox state changes in isolated mitochondria.
A portal‐arterial glucose concentration gradient as a signal for an insulin‐dependent net glucose uptake in perfused rat liver
Authors: Gardemann Andreas , Strulik Hannelore , Jungermann Kurt
Published: July 2002

Since in the usual perfusion of isolated rat liver via the portal vein an insulin‐dependent increase of hepatic glucose uptake could not be demonstrated, the possibility was considered that hepatic glucose uptake might not be a function of the absolute concentration of this substrate but of its concentration gradient between the portal vein and the hepatic artery. Therefore a new method was established for the simultaneous perfusion of isolated rat liver via both the hepatic artery (20–35% flow) and the portal vein (80–6596 flow). When glucose was offered in a concentration gradient, 9.5 mM in the portal vein and 6 mM in the hepatic artery, insulin given via both vessels caused a shift from net glucose release to uptake. This insulin‐dependent shift was not observed when glucose was offered without a gradient or with an inverse gradient, 6 mM in the portal vein and 9.5 mM in the hepatic artery. Using a portal‐arterial glucose gradient as a signal the liver might be able to differentiate between endogenous and exogenous glucose.
Bacterial lectins, cell‐cell recognition and infectious disease
Authors: Sharon Nathan
Published: July 2002

Numerous bacterial strains produce surface lectins, commonly in the form of fimbriae that are filamentous assemblies of protein subunits. Among the best characterized of these are the type 1 (mannose specific) fimbrial lectins of Escherichia coli that consist almost exclusively of one class of subunit with a molecular mass of 17 kDa. They possess an extended combining site corresponding to a trisaccharide and preferentially bind carbohydrate units of oligomannose or hybrid type. Type 1 fimbriae also possess a hydrophobic region close to the carbohydrate‐binding site, since aromatic α‐mannosides inhibit strongly (up to 1000‐times more than methyl α‐mannoside) the agglutination of yeasts by the bacteria and the adherence of the latter to pig ileal epithelial cells. The combining sites of type 1 fimbriae of the salmonellae and of other enteric bacteria are different from those of E. coli in that they are smaller and do not possess a hydrophobic region. The various bacterial surface lectins appear to function primarily in the initiation of infection by mediating bacterial adherence to epithelial cells, e.g. in the urinary and gastrointestinal tracts. The mannose specific lectins also act as recognition molecules in lectinophagocytosis (i.e. phagocytosis of the bacteria in the absence of opsonins) by mouse, rat and human peritoneal macrophages, and human polymorphonuclear leukocytes. Affinity chromatography of membrane lysates from human polymorphonuclear leukocytes on immobilized type 1 fimbrial lectin, using methyl α‐mannoside as eluent, showed that glycoproteins with apparent molecular masses of 70–80, 100 and 150 kDa act as receptors for the bacteria. Inhibition experiments with monoclonal antibodies suggest that the glycoprotein bands of 100 and 150 kDa may be identical with the α and β subunits of leukocyte complement receptors and adhesion glycoproteins involved in complement‐mediated opsonophagocytosis. The systems described serve as a fine illustration for the biological role of lectin‐carbohydrate interactions. Further studies of these systems will lead to a deeper understanding of the molecular basis of infectious diseases, and perhaps also to new approaches for their prevention.
1H NMR studies of human blood plasma Assignment of resonances for lipoproteins
Authors: Bell Jimmy D. , Sadler Peter J. , Macleod Andrew F. , Turner Peter R. , La Ville Agnes
Published: July 2002

Single‐pulse and Hahn spin‐echo 500 MHz 1H NMR spectra of human blood plasma and isolated chylomicrons, VLDL, LDL and HDL are reported. The comparison has enabled specific assignments to be made for the resonances of individual lipoproteins in the CH2 and CH3 (fatty acid), and NMe+
3 (phospholipid choline head group) regions of the spectra of plasma (0.8–1.3 and ∼ 3.25 ppm, respectively). Fasting, and freeze‐thawing of plasma samples led to marked changes in the intensities and linewidths of lipid resonances. Analysis of lipid resonances in the spectra of plasma in terms of individual lipoproteins may shed new light on many conditions of clinical and biochemical interest.
Biologically significant scavenging of the myeloperoxidase‐derived oxidant hypochlorous acid by ascorbic acid
Authors: Halliwell Barry , Wasil Mohammed , Grootveld Martin
Published: July 2002

Ascorbic acid, at physiological concentrations, can scavenge the myeloperoxidase‐derived oxidant hypochlorous acid at rates sufficient to protect α1‐antiprotease against inactivation by this molecule. The rapid depletion of ascorbic acid at sites of inflammation, as in the inflamed rheumatoid joint, may therefore facilitate proteolytic damage.
Estrogen‐controlled gene expression in tissue culture cells by zearalenone
Authors: Mayr Ulrich E.
Published: July 2002

In two estrogen‐sensitive cell lines, Le42 and MCF‐7, the estrogenic potential of the nonsteroidal mycotoxin zearalenone has been investigated. The chloramphenicol acetyltransferase (CAT) gene expression in Le42 cells is induced by zearalenone after transfection with a CAT‐gene construct controlled by an estrogen responsive element [(1986) Cell 46, 1053–1061]. In MCF‐7 cells zearalenone induces at least 2 exoproteins (52 and 160 kDa) which are estrogen‐specific [(1980) Cell 20, 353–362). These data suggest that zearalenone acts by activating the estrogen receptor. Due to the high sensitivity of these cell lines for zearalenone both test systems are proposed as assays for a quantitative estimation of the biological (estrogenic) activity of this widespread mycotoxin.
Immunodetection of Na,K‐ATPase α3‐isoform in renal and nerve tissues
Authors: Arystarkhova E.A. , Lakhtina O.E. , Modyanov N.N.
Published: July 2002

At least three types of mRNA of the catalytic subunit of Na,K‐ATPase namely α‐,α+‐ and α3‐isoforms are identified in different tissues. Only two of them α and α+ have well known structural and catalytic properties. Here we present immunochemical data indicating that the α3 protein really exists in pig and human kidney, and human brain. Crude membrane fractions and purified membrane‐bound Na,K‐ATPases were immunoblotted with α3‐specific antibodies raised against the synthetic peptide corresponding to the unique sequence of this isoform. The mature α3‐subunit is shown to include the sequence GDKKDDKSSPK followed by the initiating methionine residue. Nephron collecting tubules are proposed to specifically contain Na,K‐ATPase α3‐isoform.
Molecular structure of the human alcohol dehydrogenase 1 gene
Authors: Matsuo Yoshinori , Yokoyama Shozo
Published: July 2002

The structure and nucleotide sequence of an allele at the ADH1 locus have been determined. The nucleotide sequence of this allele is identical to that of a cDNA clone [(1986) Biochemistry 25, 2465–2470] and the intron positions of the ADH1 gene are identical to that of the ADH2 gene [(1986) J. Biol. Chem. 261, 2027–2033].
Inhibition of cGMP‐dependent protein kinase by (Rp)‐guanosine 3',5'‐monophosphorothioates
Authors: Butt Elke , Van Bemmelen Michael , Fischer Lilo , Walter Ulrich , Jastorff Bernd
Published: July 2002

The activation of the cGMP‐dependent protein kinase and cAMP‐dependent protein kinase by the diastereomers of guanosine 3',5'‐monophosphorothioate, (Sp)‐cGMPS and (Rp)‐cGMPS, and 8‐chloroguanosine 3',5'‐monophosphorothioate, (Sp)‐8‐Cl‐cGMPS and (Rp)‐8‐Cl‐cGMPS, was investigated using the peptide Kemptide as substrate. The (Sp)‐diastereomers, which have an axial exocyclic sulfur atom, bound to the cGMP‐dependent protein kinase and stimulated its phosphotransferase activity. In contrast, the (Rp)‐isomers, which have an equatorial exocyclic sulfur atom, bound to the enzyme without stimulation of its activity. (Rp)‐cGMPS and (Rp)‐8‐Cl‐cGMPS antagonized the activation of the cGMP‐dependent protein kinase with a K
i of 20 μM and 1.5 μM, respectively. (Rp)‐cGMPS also antagonized the activation of cAMP‐dependent protein kinase with a K
i of 20 μM. In contrast, (Rp)‐8‐Cl‐cGMPS was a weak inhibitor of the cAMP‐dependent protein kinase with a K
i of 100 μM. (Rp)‐8‐Cl‐cGMPS appears to be a rather selective inhibitor of the cGMP‐dependent protein kinase and may be a useful tool for studying the role of cGMP in broken and intact cell systems.
Two of the three actin‐binding domains of gelsolin bind to the same subdomain of actin Implications for capping and severing mechanisms
Authors: Pope B. , Way M. , Weeds A.G.
Published: July 2002

Gelsolin binds two monomers in the nucleating complex with G‐actin in calcium and caps actin filaments. However, 3 actin‐binding domains have been identified within its 6 repeating sequence segments corresponding to S1,S2–3 and S4–6, S1 and S4–6 bind only G‐actin whereas S2–3 binds specifically to F‐actin. Two of the three domains (S2–3 and S4–6) are required for nucleation and a different pair (S1 and S2–3) for severing. Here we show for the first time that the domains unique to nucleation (S4–6) or severing (S1) compete for the same region on subdomain 1 of G‐actin. We further show that S2–3 binds actin monomers weakly in G‐buffer conditions and that this interaction persists when S1 or S4–6 are also bound. Thus gelsolin associates with two distinct regions on actin. Since S2–3 does not bind monomeric actin in F‐buffer, we suggest that its high affinity 1:1 stoichiometry for filament subunits reflects interaction with two adjacent subunits.
Localization of metallothionein in nuclei of growing primary cultured adult rat hepatocytes
Authors: Tsujikawa Kazutake , Imai Takumi , Kakutani Makoto , Kayamori Yuzo , Mimura Tsutomu , Otaki Noriko , Kimura Masami , Fukuyama Ryuichi , Shimizu Nobuyoshi
Published: July 2002

In primary cultured adult rat hepatocytes stimulated by epidermal growth factor and insulin, dramatic changes in the subcellular distribution of metallothionein were clarified by indirect immunofluorescence using antisera specific for this protein. Metallothionein was detected only in the cytoplasm of cultured hepatocytes in the G0 and G1 phases, but was concentrated in the cell nuclei in the early S phase. The strongest staining pattern in the nuclei was observed 12 h after stimulation. Subsequently, the intensity of metallothionein staining in the nuclei decreased. These results suggests that primary cultured hepatocytes are suitable for examining the relation between subcellular localization of metallothionein and cell growth.
Rapid purification and characterisation of HIV‐1 reverse transcriptase and RNaseH engineered to incorporate a C‐terminal tripeptide α‐tubulin epitope
Authors: Stammers D.K. , Tisdale M. , Court S. , Parmar V. , Bradley C. , Ross C.K.
Published: July 2002

The C‐termini of p66 and p51 forms of HIV‐1 reverse transcriptase have been engineered to contain a Glu‐Glu‐Phe sequence recognized by a monoclonal antibody to α‐tubulin YL. Mututed RTs were purified in a single step using peptide elution from columns of immobilized YL. The known sequence requirements of the YL epitope arc consistent with protein eluting from the column with an intact C‐terminus. Kinetic parameters of these mutated RTs are essentially unchanged from wild‐type enzyme. The p15 RNaseH domain has been purified using this method and shown to have low enzyme activity compared to the parental p66 subunit.
Extended N‐terminal sequencing of proteins of the large ribosomal subunit from yeast mitochondria
Authors: Grohmann Lutz , Graack Hanns-Rüdiger , Kruft Volker , Choli Theodora , Goldschmidt-Reisin Sabine , Kitakawa Madoka
Published: July 2002

We have determined the N‐termini of 26 proteins of the large ribosomal subunit from yeast mitochondria by direct amino acid micro‐sequencing. The N‐terminal sequences of proteins YmL33 and YmL38 showed a significant similarity to eubacterial ribosomal (r‐) proteins L30 and L14, respectively. In addition, several proteins could be assigned to their corresponding yeast nuclear genes. Based on a comparison of the protein sequences deduced from the corresponding DNA regions with the N‐termini of the mature proteins, the putative leader peptides responsible for mitochondrial matrix‐targeting were compiled. In most leader sequences a relative abundance of aromatic amino acids, preferentially phenylalanine, was found.
Protein prenylation in Schizosaccharomyces pombe
Authors: Giannakouros Thomas , Armstrong John , Magee Anthony I.
Published: July 2002

S. pombe is shown to be a powerful system for studies concerning attachment or polyisoprenoid moieties to proteins, due to its ability to take up exogenous mevalonic acid efficiently. The fission yeast can take up about 5% of the exogenously added mevalonic acid and incorporate ∼10% of this into protein. By contrast, the uptake obtained with the budding yeast S. cerevisiae is less than 0.5% HPLC analysis of total S. pombe protein‐bound isoprenoids revealed that ∼55% of the counts co‐migrated with the geranylgeraniol standard, while ∼45 of the counts co‐migrated with farnesol. We could not detect any effects of mevinolin or other HMG‐CoA reductase inhibitors in S. pombe.
Molecular cloning and characterization of human endothelial nitric oxide synthase
Authors: Marsden Philip A. , Schappert Keith T. , Chen Hai Sheine , Flowers Michele , Sundell Cynthia L. , Wilcox Josiah N. , Lamas Santiago , Michel Thomas
Published: July 2002

The constitutive calcium/calmodulin‐dependent nitric oxide (NO) synthase expressed in vascular endothelium shares common biochemical and pharmacologic properties with neuronal NO synthase. However, recent cloning and molecular characterization of NO synthase from bovine endothelial cells indicated the existence of a family of constitutive NO synthases. Accordingly, we undertook molecular cloning and sequence analysis of human endothelial NO synthase. Complementary DNA clones predict a protein of 1,203 amino acids sharing 94% identity with the bovine endothelial protein, but only 60% identity with the rat brain NO synthase isoform. Northern blot analysis with an endothelial‐derived cDNA identified a 4.6–4.8 kb mRNA transcript in HUVEC and in situ hybridization localized transcripts to vascular endothelium but not neuronal tissue.
Carboxyl‐terminal processing may be essential for production of active NiFe hydrogenase in Azotobacter vinelandii
Authors: Gollin David J. , Mortenson Leonard E. , Robson Robert L.
Published: July 2002

The NiFe hydrogenase from Azotobacter vinelandii is a membrane‐bound αβ heterodimer that can oxidize H2 to protons and electrons and thereby provide energy. Genes encoding the α and β subunits, hoxG and hoxK respectively, followed by thirteen contiguous accessory genes potentially involved in H2 oxidation, have been previously sequenced. Mutations in some of these accessory genes give rise to inactive enzyme containing an α subunit with decreased electrophoretic mobility. Mass spectral analysis of the subunits demonstrated that the α subunit had a molecular weight 1,663 Da less than that predicted from hoxG. Since the N‐terminal sequence of the purified α subunit matches the sequence predicted from hoxG we suggest this difference is due to removal of the C‐terminus of the α subunit which may be an important step linked to metal insertion, localization, and formation of active hydrogenase.
Expression of protein kinase C subspecies in rat retina
Authors: Fujisawa Naoko , Ogita Kouji , Saito Naoaki , Nishizuka Yasutomi
Published: July 2002

An extract of rat retina was subjected to Mono Q followed by chromatography on hydroxyapatite, and the protein kinase C (PKC) subspecies were identified by immunobiol and biochemical analysis. It was found that, although the relative activities assayed with myelin basic protein as a common phosphate acceptor vary greatly with one another, the α‐, βI‐, βII‐, γ‐, δ‐, ε‐, ξ‐, and another structurally unknown PKC subspecies are expressed in this tissue. Thus, the retina is a unique tissue which expresses most of the PKC subspecies so far identified in mammals.
Reconstitution of functional muscarinic receptors by co‐expression of amino‐ and carboxyl‐terminal receptor fragments
Authors: Maggio Roberto , Vogel Zvi , Wess Jürgen
Published: July 2002

Truncated m2 and m3 muscarinic receptors (referred to as m2‐ and m3‐trunc), containing transmembrane domains I‐V and the N‐terminal portion of the third cytoplasmic loop, were co‐expressed in COS‐7 cells with the corresponding C‐tenninal receptor fragments (referred to as m2‐ and m3‐tail; containing transmembrane domains VI and VII). Expression of any of these four polypeptides alone did not result in any detectable [3H]N‐methylscopolamine ([3H]NMS) binding activity. However, specific [3H]NMS binding sites were observed after co‐expression of m2‐trunc with m2‐tail and m3‐trunc with m3‐tail. These sites displayed ligand binding properties similar to those of the two wild‐type receptors. The ‘reconstituted’ m3‐trunc/m3‐tail receptor was also able to stimulate agonist‐dependent phosphatidyl inositol hydrolysis in a fashion similar to the wild‐type m3 receptor, whereas all other polypeptide combinations were inactive. These data suggest that muscarinic receptors are assembled in a fashion analogous to two‐subunit receptors.
Structure and localization of mRNA encoding a pigment dispersing hormone (PDH) in the eyestalk of the crayfish Orconectes limosus
Authors: de Kleijn Dominique P.V. , Linck Birgit , Klein Jörg M. , Weidemann Wolfgang M. , Keller Rainer , van Herp François
Published: July 2002

The pigment‐dispersing hormone (PDH) is produced in the eyestalks of Crustacea where it induces light‐adapting movements of pigment in the compound eye and regulates the pigment dispersion in the chromatophores. To study this hormone at the mRNA level, we cloned and sequenced cDNA encoding PDH in the crayfish Orconectes limosus. The structure of the PDH preprohormone consists of a signal peptide, a PDH precursor‐related peptide (PPRP) and the highly conserved PDH peptide at the carboxy‐terminal end. In situ hybridization in combination with immunocytochemistry revealed four cell clusters expressing PDH in the optic ganglia of the eyestalk. Three clusters stained both with the PDH cRNA probe and the PDH antiserum, however, the perikarya in the lamina ganglionaris (LG) only stained with the PDH antiserum, suggesting the presence of a PDH‐like peptide in the LG.
Carboxy‐terminal processing of the large subunit of [NiFe] hydrogenases
Authors: Menon Nanda K. , Robbins Jeff , Der Vartanian Marie , Patil Daulat , Peck Harry D. , Menon Angeli L. , Robson Robert L. , Przybyla Alan E.
Published: July 2002

Two electrophoretic forms of the large subunit of the soluble periplasmic [NiFe] hydrogenase from Desulfovibrio gigas have been detected by Western analysis. The faster moving form co‐migrates with the large subunit from purified, active enzyme. Amino acid sequence and composition of the C‐terminal tryptic peptide of the large subunit from purified hydrogenase revealed that it is 15 amino acids shorter than that predicted by the nucleotide sequence. Processing of the nascent large subunit occurs by C‐terminal cleavage between His536 and Val537, residues which are highly conserved among [NiFe] hydrogenases. Mutagenesis of the analogous residues, His582 and Val583, in the E. coli hydrogenase‐1 (HYD1) large subunit resulted in significant decrease in processing and HYD1 activity.
5‐lipoxygenase‐activating protein is an arachidonate binding protein
Authors: Mancini Joseph A. , Abramovitz Mark , Cox Martha E. , Wong Elizabeth , Charleson Stella , Perrier Hélène , Wang Zhaoyin , Prasit Peptiboon , Vickers Philip J.
Published: July 2002

5‐Lipoxygenase‐activating protein (FLAP) is an 18‐kDa integral membrane protein which is essential for cellular leukotriene (LT) synthesis, and is the target of LT biosynthesis inhibitors. However, the mechanism by which FLAP activates 5‐LO has not been determined. We have expressed high levels of human FLAP in Spodoptera frugiperda (Sf9) insect cells infected with recombinant baculovirus, and used this system to demonstrate that FLAP specifically binds [125I]L‐739,059, a novel photoaffinity analog of arachidonic acid. This binding is inhibited by both arachidonic acid and MK‐886, an LT biosynthesis inhibitor which specifically interacts with FLAP. These studies suggest that FLAP may activate 5‐LO by specifically binding arachidonic acid and transferring this substrate to the enzyme.
Development of congenic strains of mice carrying amyloidogenic apolipoprotein A‐II (Apoa2c)
Authors: Higuchi Keiichi , Kitado Haruo , Kitagawa Kaori , Kogishi Kumiko , Naiki Hironobu , Takeda Toshio
Published: July 2002

A congenic strain of mice with amyloidogenic apolipoprotein A‐II (Apoa2c) on the genetic background of the amyloidosis‐resistant SAM‐R/1 strain was produced by 12 generations of backcrossing. Genome mapping using endogenous murine leukemia proviral markers was done in the congenic strain, termed R1·P1‐Apoa2c. We confirmed that only a small region surrounding the apoA‐II gene on chromosome 1 was transferred from the genome of the donor SAM‐P/1 strain. The level and particle size of plasma high density lipoprotein were decreased in RI · Pl‐Apoa2c mice compared to those in the progenitor SAM‐R/1 mice. The function of apoA‐II can be studied using this strain of mice.
An investigation of the abnormal metabolic status of synovial fluid from patients with rheumatoid arthritis by high field proton nuclear magnetic resonance spectroscopy
Authors: Naughton Declan , Whelan Michael , Smith Elaine C. , Williams Richard , Blake David R. , Grootveld Martin
Published: July 2002

The 1H Hahn spin‐echo NMR profiles of rheumatoid synovial fluids have been investigated and compared with those of matched serum samples. In addition to markedly elevated lactate and diminished glucose concentrations, inflammatory synovial fluids contained (i) substantially lower levels of NMR‐detectable chylomicron‐ and very‐low‐density‐lipoprotein‐associated triacylglycerols which appear to have a shortened mean chain‐length, and (ii) high concentrations of ketone bodies (predominantly 3‐d‐hydroxybutyrate), relative to those of corresponding paired serum samples. These observations confirm the abnormal metabolic status of the inflamed rheumatoid joint and provide evidence for an increased utilisation of lipids for fuel therein.
Na+,K+‐ATPase of gastric cells A target of Helicobacter pylori cytotoxic activity
Authors: Ricci V. , Sommi P. , Cova E. , Fiocca R. , Romano M. , Ivey K.J. , Solcia E. , Ventura U.
Published: July 2002

The present study shows a direct impairing action of a cytotoxin‐producing Helicobacter pylori strain on the Na+,K−‐ATPase (evaluated as K+‐dependent phosphatase activity) of human gastric epithelial cells in culture. The toxin itself is likely involved in this action which may also account for the cell edema found in vivo in Helicobacter pylori‐colonized stomach.
Molecular mechanism of action of Pb2+ and Zn2+ on water oxidizing complex of photosystem II
Authors: Rashid Abdur , Camm Edith L. , Ekramoddoullah Abul K.M.
Published: July 2002

Pb2+ and Zn2+ inhibition of photosystem II (PSII) activity was reported to be mediated via displacement of native inorganic cofactors (Cl−, Ca2+ and Mn2+) from the oxygen evolving complex, OEC [Rashid and Popovic (1990) FEBS Lett. 271, 181–184; Rashid et al. (1991) Photosynth. Res. 30, 123–130]. Since the binding sites of these cofactors are protected by a shield of three extrinsic polypeptides (17, 23 and 33 kDa), we investigated whether these metal ions affect the extrinsic polypeptide shield of OEC. By immunoblotting with antibodies recognizing the 23 and 33 kDa polypeptides, we showed that both the metal ions significantly dissociated the 23 kDa (+17 kDa) polypeptide, and partially dissociated the 33 kDa. Ca2+, one of the important inorganic cofactors of oxygen evolution, strongly prevented the dissociating action of Pb2+ but did not prevent the action of Zn2+. The probable molecular mechanism of action of Pb2+ and Zn2+ on PSII OEC is discussed.
Formation of 50 kbp chromatin fragments in isolated liver nuclei is mediated by protease and endonuclease activation
Authors: Zhivotovsky Boris , Wade David , Gahm Annie , Orrenius Sten , Nicotera Pierluigi
Published: July 2002

Isolated rat liver nuclei were incubated in the presence of divalent cations, and the mechanisms underlying the subsequent chromatin fragmentation were investigated. Either of the two cations, Ca2+ or Mg2+ was sufficient to produce chromatin fragments with sizes between 700 and 300 kbp. The formation of chromatin fragments of 50 kbp as well as the following internucleosomal DNA cleavage ‐ which are characteristic of apoptosis ‐ were markedly stimulated in the presence of Ca2+. Chromatin degradation to 50 kbp and smaller (oligonucleosome‐size) fragments was prevented by inhibitors of endonucleases and serine proteases. We suggest a mechanism whereby the concerted activity of both proteases and endonucleases results in the widespread chromatin cleavage observed in cellls undergoing apoptosis.
Oxidative DNA base damage and antioxidant enzyme activities in human lung cancer
Authors: Jaruga Pawel , Zastawny Tomasz H. , Skokowski Jan , Dizdaroglu Miral , Olinski Ryszard
Published: July 2002

We have investigated levels of antioxidant enzymes and free radical‐induced DNA base modifications in human cancerous lung tissues and in their cancer‐free surrounding tissues. Various DNA base lesions in chromatin of lung tissues were measured by gas chromatography‐mass spectrometry. Activities of superoxide dismutase, catalase and glutathione peroxidase were also measured in lung tissues. Higher levels of DNA lesions were observed in cancerous tissues than in cancer‐free surrounding tissues. Antioxidant enzyme levels were lower in cancerous tissues. The results indicate an association between decreased activities of antioxidant enzymes and increased levels of DNA lesions in cancerous tissues. Higher levels of DNA lesions suggest that free radical reactions may be increased in malignant tumor cells.
High‐level expression of fully active human glutaredoxin (thioltransferase) in E. coli and characterization of Cys7 to Ser mutant protein
Authors: Alicia Padilla C. , Spyrou Giannis , Holragren Arne
Published: July 2002

Glutaredoxin (Grx) (12 kDa) is a hydrogen donor for ribonucleotide reductase and also a general GSH‐disulfide reductase of importance for redox regulation. To overexpress human glutaredoxin in Escherichia coli, a cDNA encoding human Grx was modified and cloned into the vector pET‐3d and expressed in E. coli BL21(DE3) by IPTG induction. High‐level expression of Grx was verified by GSH‐disulfide oxidoreductase activity, SDS‐PAGE and immunoblotting analysis. The recombinant human Grx in its reduced form was purified to homogenity with 50% yield and exhibited the same dehydroascorbate reductase and hydrogen donor activity for ribonucleotide reductase (K
m ∼ 0.2 μM) as the human placenta protein. Human Grx contains a total of 5 half‐cystine residues including a non‐conserved Cys7 residue and is easily oxidized to form dimers during storage. A Grx mutant Cys7 to Ser was generated by site‐directed mutagenesis and the protein was purified to homogeneity. The mutant protein showed full activity and exhibited a much reduced tendency to form dimers compared with the wild type protein. Peptide sequencing confirmed the mutation and removal of the N‐terminal Met residue in both wild type and mutant proteins. Fluorescence spectra demonstrated only tyrosine fluorescence in human Grx with a peak at 310 nm which increased 20% upon reduction and decreased by addition of GSSG demonstrating that glutathionecontaining disulfides are excellent substrates.
Active peptides from the carboxyl‐terminal globular domain of laminin α2 and Drosophila α chains
Authors: Nomizu Motoyoshi , Song Sang-Yong , Kuratomi Yuichiro , Tanaka Masahiko , Woo Ho Kim , Kleinman Hynda K. , Yamada Yoshihiko
Published: July 2002

The laminin α1 chain carboxyl‐terminal globular domain (G domain) contains multiple biological activities. Recently, we identified five cell binding sequences from the G domain by screening with overlapping 12‐mer peptides encompassing the entire domain. The structures of these five sequences in the α1 chain are conserved in the corresponding regions of the different laminin α chains. Here we characterize the adhesion activities of the corresponding peptide segments from both the mouse laminin α2 chain and Drosophila laminin α chain using peptide‐coated plastic plates and peptide‐conjugated Sepharose beads. Using several cell lines, the laminin α2 chain peptides showed cell attachment and/or spreading activities with cell type specificities. Cell spreading on MG‐10 was inhibited by integrin antibodies. Four of the Drosophila laminin peptides showed cell attachment activities. These results suggest that biologically active regions in the G domain are conserved in the laminin α1 and α2 chains, and that these regions in laminin play an important role in cell surface receptor interactions.
Ethanol neurotoxicity on neuroblast‐enriched cultures from three‐day‐old chick embryo is attenuated by the neuronotrophic action of GABA
Authors: Spoerri P.E. , Srivastava N. , Vernadakis A.
Published: July 2002

In the present study, using neuroblast‐enriched cultures derived from three‐day‐old chick embryos (E3WE), we examined the morphological effects of ethanol and/or GABA, as well as the developmental profile of the cholinergic and GABAergic neuronal phenotypes, as assessed by the activities of choline acetyltransferase (ChAT) and glutamate decarboxylase (GAD). Cultures exposed to ethanol (50 mM) exhibited smaller and fewer aggregates than controls with a neuritic network that lacked fasciculation. In cultures treated with GABA (10−5 M) alone or ethanol + GABA the size and number of the neuronal aggregates was increased and also neuritic arborization and fasciculation was enhanced. Thus, addition of GABA restored the normal growth pattern in the ethanol‐treated cultures. As previously shown, E3WE culture treated with ethanol alone showed a decrease in both ChAT and GAD activities compared to controls. Both cholinergic and GABAergic neuronal phenotypes were enhanced in cultures treated with GABA as assessed by increases in ChAT and GAD activities, respectively, compared to controls. Moreover, in cultures treated concomitantly with ethanol and GABA both ChAT and GAD activities were higher than in ethanol‐alone‐treated cultures. Thus, the presence of GABA in the ethanol‐treated cultures counteracted the decline in ChAT and GAD activities observed in the ethanol‐alone‐treated cultures. We concluded that GABA through its neuronotrophic actions can rescue neuroblasts from ethanol insult and restore neuronal phenotypes.
Measuring the unmeasurable: the role and importance of quality of life measurement in economic evaluations of sleep disorder treatment
Authors: der Schulenburg JM Graf von
Published: July 2002

Sleep disorder is a widespread chronic disease. Its treatment and the disease itself causes losses to society, eg treatment cost and cost of sick leaves. On the other hand an appropriate treatment increases patients' quality of life and work productivity. The basic methods for evaluating the costs and benefits of treating sleep disorders are described.
Internal validation of a French version of the Dutch eating behaviour questionnaire
Authors: Lluch A , Kahn JP , Stricker-Krongrad A , Ziegler O , Drouin P , Méjean L
Published: July 2002

This study is the first part of the validation of a French version of the Dutch Eating Behaviour Questionnaire (DEBQ), among a population of obese and normal-weight patients. The questionnaire was administered to 166 subjects. Construct validity was assessed by orthogonal factor analysis with a varimax procedure and reliability was measured by Cronbach's alpha coefficient. Results showed the presence of three major factors (“emotional”, “restrained” and “external eating”) with loadings similar to those of the original questionnaire. A high internal consistency was found in the different scales. This study clearly demonstrates the factorial validity and the reliability of a French version of the DEQB.
Mutilation of RNA phage Qβ virus‐like particles: from icosahedrons to rods
Authors: Cielens Indulis , Ose Velta , Petrovskis Ivars , Strelnikova Anna , Renhofa Regina , Kozlovska Tatyana , Pumpens Paul
Published: July 2002

Icosahedral virus‐like particles (VLPs) of RNA phage Qβ are stabilized by four disulfide bonds of cysteine residues 74 and 80 within the loop between β‐strands F and G (FG loop) of the monomeric subunits, which determine the five‐fold and quasi‐six‐fold symmetry contacts of the VLPs. In order to reduce the stability of Qβ VLPs, we mutationally converted the amino acid stretch 76‐ANGSCD‐81 within the FG loop into the 76‐VGGVEL‐81 sequence. It led to production in Escherichia coli cells of aberrant rod‐like Qβ VLPs, along with normal icosahedral capsids. The length of the rod‐like particles exceeded 4–30 times the diameter of icosahedral Qβ VLPs.