bluuebunny/crossref_metadata_2025 huggingface dataset:
The development of health insurance system in China in the period of socialist modernization (1978 – 2001)
Authors: Lyu Khentsze
Published: October 2020

  This article explores the development of health insurance system in China over the period from 1978 to 2001. The author reviews the implementation of market mechanisms in health insurance system; provides statistical data on the number of insured persons residing in the city or rural localities. Analysis is conducted on legislation that regulates insurance activity in the sphere of medicine. The conclusion is made that the implementation of such systems affected by migration from rural to urban areas led to imbalance in the quality and availability of medical services. It is noted that despite the efforts of Chinese authorities, health insurance system did not expand neither the number of insured rural or urban residents; dependence of the level of medical care on the level of salaries led to segregation of rich and poor citizens. The employees with insufficient salary level were trying to reduce the cost treatment, as it partially compensated from their personal savings, which also led to severe sanitary consequences. Therefore, the implementation of market mechanisms in health insurance led to inequality of the citizens with regards to availability of medical services.  
Problem of the meaning of life in Russian philosophy and its reflection in the worldview of modern student youth
Authors: Sytykh Olga Leonidovna , Sintsova Lyudmila Konstantinovna
Published: October 2020

The subject of this research is the problem of the meaning of life in Russian philosophy and in perception of modern students. Based on the analysis of essays on the topic “The problem of the meaning of life in Russian philosophy and personal perspective on the problem” written by the students of Altai State University, it was determined that the students understand the positions of Russian philosophers in this regard, accept or reject certain points of view described in their philosophical works. Main attention is given to the personal perspective of students on the meaning of life. The article compares the results of analysis of the essays with sociological research presented in the literature. The author revels the life-meaning orientations of modern student youth and their stance on one of the fundamental problems of Russian philosophy. Freedom in choosing the path of life, and right to seek their meaning in life, fulfilling of personal creative potential, good intentions – these are the ideas of Russian philosophers most affined to modern students. The students expressed both negative and positive opinions on the writings of Russian philosophers, which is an expected result of comprehension of a profound topic and attempt at self-determination in modern realties.
Cerebellar patients have intact feedback control that can be leveraged to improve reaching
Authors: Zimmet Amanda M , Cao Di , Bastian Amy J , Cowan Noah J
Published: October 2020

It is thought that the brain does not simply react to sensory feedback, but rather uses an internal model of the body to predict the consequences of motor commands before sensory feedback arrives. Time-delayed sensory feedback can then be used to correct for the unexpected—perturbations, motor noise, or a moving target. The cerebellum has been implicated in this predictive control process. Here, we show that the feedback gain in patients with cerebellar ataxia matches that of healthy subjects, but that patients exhibit substantially more phase lag. This difference is captured by a computational model incorporating a Smith predictor in healthy subjects that is missing in patients, supporting the predictive role of the cerebellum in feedback control. Lastly, we improve cerebellar patients’ movement control by altering (phase advancing) the visual feedback they receive from their own self movement in a simplified virtual reality setup.
Eater cooperates with Multiplexin to drive the formation of hematopoietic compartments
Authors: Csordás Gábor , Grawe Ferdinand , Uhlirova Mirka
Published: October 2020

Blood development in multicellular organisms relies on specific tissue microenvironments that nurture hematopoietic precursors and promote their self-renewal, proliferation, and differentiation. The mechanisms driving blood cell homing and their interactions with hematopoietic microenvironments remain poorly understood. Here, we use the Drosophila melanogaster model to reveal a pivotal role for basement membrane composition in the formation of hematopoietic compartments. We demonstrate that by modulating extracellular matrix components, the fly blood cells known as hemocytes can be relocated to tissue surfaces where they function similarly to their natural hematopoietic environment. We establish that the Collagen XV/XVIII ortholog Multiplexin in the tissue-basement membranes and the phagocytosis receptor Eater on the hemocytes physically interact and are necessary and sufficient to induce immune cell-tissue association. These results highlight the cooperation of Multiplexin and Eater as an integral part of a homing mechanism that specifies and maintains hematopoietic sites in Drosophila.
Collagen-rich omentum is a premetastatic niche for integrin α2-mediated peritoneal metastasis
Authors: Huang Yen-Lin , Liang Ching-Yeu , Ritz Danilo , Coelho Ricardo , Septiadi Dedy , Estermann Manuela , Cumin Cécile , Rimmer Natalie , Schötzau Andreas , Núñez López Mónica , Fedier André , Konantz Martina , Vlajnic Tatjana , Calabrese Diego , Lengerke Claudia , David Leonor , Rothen-Rutishauser Barbara , Jacob Francis , Heinzelmann-Schwarz Viola
Published: October 2020

The extracellular matrix (ECM) plays critical roles in tumor progression and metastasis. However, the contribution of ECM proteins to early metastatic onset in the peritoneal cavity remains unexplored. Here, we suggest a new route of metastasis through the interaction of integrin alpha 2 (ITGA2) with collagens enriched in the tumor coinciding with poor outcome in patients with ovarian cancer. Using multiple gene-edited cell lines and patient-derived samples, we demonstrate that ITGA2 triggers cancer cell adhesion to collagen, promotes cell migration, anoikis resistance, mesothelial clearance, and peritoneal metastasis in vitro and in vivo. Mechanistically, phosphoproteomics identify an ITGA2-dependent phosphorylation of focal adhesion kinase and mitogen-activated protein kinase pathway leading to enhanced oncogenic properties. Consequently, specific inhibition of ITGA2-mediated cancer cell-collagen interaction or targeting focal adhesion signaling may present an opportunity for therapeutic intervention of metastatic spread in ovarian cancer.
Relationships Between Total Cholesterol Levels and Specific Alterations in Impulsivity and Attention
Authors: GENDLE MATHEW H. , GLAZER KIMBERLY S. , OLSZEWSKI ELIZABETH A. , NOVAK CINDY A.
Published: October 2020

The relationship between total cholesterol (TC) levels in whole blood and error rates on the Conners Continuous Performance Test II (CPT; a standardized computer-based assessment of visual attention and reaction time) was investigated in a sample of generally healthy adults, and followed up previous research that tentatively suggested a positive relationship between TC and behavioral impulsivity. TC levels were gathered from capillary blood samples taken from each participant (n  =  30). Measures of life stress and various socio-demographic and health variables were also obtained. Each participant also completed the CPT, and a covariate-adjusted analysis was completed to examine the relationship between TC and CPT performance. Adjusting for several relevant covariates, increases in TC were significantly positively associated with a greater rate of CPT commission errors, which are widely assumed to serve as an indicator of behavioral impulsivity. Noteworthy behavioral consequences of elevated TC may exist, particularly in situations that require impulse control and sustained visual attention.
Changes in North Carolina's Marine Fish Faunas: Good or Bad?
Authors: Schwartz Frank J.
Published: October 2020

Populations of 86 Atlantic Ocean marine fishes have changed during the last 45 years off North Carolina. Examination of the ocean conditions and its fish faunal interrelationships explain reasons for these changes.
A digital mapping application for quantifying and displaying air temperatures at high spatiotemporal resolutions in near real-time across Australia
Authors: Webb Mathew , Minasny Budiman
Published: October 2020

Surface air temperature (Ta) required for real-time environmental modelling applications should be spatially quantified to capture the nuances of local-scale climates. This study created near real-time air temperature maps at a high spatial resolution across Australia. This mapping is achieved using the thin plate spline interpolation in concert with a digital elevation model and ‘live’ recordings garnered from 534 telemetered Australian Bureau of Meteorology automatic weather station (AWS) sites. The interpolation was assessed using cross-validation analysis in a 1-year period using 30-min interval observation. This was then applied to a fully automated mapping system—based in the R programming language—to produce near real-time maps at sub-hourly intervals. The cross-validation analysis revealed broad similarities across the seasons with mean-absolute error ranging from 1.2 °C (autumn and summer) to 1.3 °C (winter and spring), and corresponding root-mean-square error in the range 1.6 °C to 1.7 °C. The R2 and concordance correlation coefficient (Pc ) values were also above 0.8 in each season indicating predictions were strongly correlated to the validation data. On an hourly basis, errors tended to be highest during the late afternoons in spring and summer from 3 pm to 6 pm, particularly for the coastal areas of Western Australia. The mapping system was trialled over a 21-day period from 1 June 2020 to 21 June 2020 with majority of maps completed within 28-min of AWS site observations being recorded. All outputs were displayed in a web mapping application to exemplify a real-time application of the outputs. This study found that the methods employed would be highly suited for similar applications requiring real-time processing and delivery of climate data at high spatiotemporal resolutions across a considerably large land mass.
COVID-19: molecular and serological detection methods
Authors: Dhamad Ahmed E. , Abdal Rhida Muna A.
Published: October 2020

Since COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was declared as a pandemic disease by the World Health Organization in early 2020, many countries, organizations and companies have tried to find the best way to diagnose the virus and contain its spreading. SARS-CoV-2 is a positive-sense single RNA (+ssRNA) coronavirus and mainly spreads through droplets, respiratory secretions, and direct contact. The early detection of the virus plays a central role in lowering COVID19 incidents and mortality rates. Thus, finding a simple, accurate, cheap and quick detection approach for SARS-CoV-2 at early stage of the viral infection is urgent and at high demand all around the world. The Food and Drug Administration and other health agencies have declared Emergency Use Authorization to develop diagnostic methods for COVID-19 and fulfill the demand. However, not all developed methods are appropriate and selecting a suitable method is challenging. Among all detection methods, rRT-PCR is the gold standard method. Unlike molecular methods, serological methods lack the ability of early detection with low accuracy. In this review, we summarized the current knowledge about COVID-19 detection methods aiming to highlight the advantages and disadvantages of molecular and serological methods.
Effects of taphonomic deformation on geometric morphometric analysis of fossils: a study using the dicynodontDiictodon feliceps(Therapsida, Anomodontia)
Authors: Kammerer Christian F. , Deutsch Michol , Lungmus Jacqueline K. , Angielczyk Kenneth D.
Published: October 2020

Taphonomic deformation, the distortion of fossils as a result of geological processes, poses problems for the use of geometric morphometrics in addressing paleobiological questions. Signal from biological variation, such as ontogenetic trends and sexual dimorphism, may be lost if variation from deformation is too high. Here, we investigate the effects of taphonomic deformation on geometric morphometric analyses of the abundant, well known Permian therapsidDiictodon feliceps. DistortedDiictodoncrania can be categorized into seven typical styles of deformation: lateral compression, dorsoventral compression, anteroposterior compression, “saddle-shape” deformation (localized collapse at cranial mid-length), anterodorsal shear, anteroventral shear, and right/left shear. In simulated morphometric datasets incorporating known “biological” signals and subjected to uniform shear, deformation was typically the main source of variance but accurate “biological” information could be recovered in most cases. However, in empirical datasets, not only was deformation the dominant source of variance, but little structure associated with allometry and sexual dimorphism was apparent, suggesting that the more varied deformation styles suffered by actual fossils overprint biological variation. In a principal component analysis of all anomodont therapsids, deformedDiictodonspecimens exhibit significant dispersion around the “true” position of this taxon in morphospace based on undistorted specimens. The overall variance associated with deformation for Anomodontia as a whole is minor, and the major axes of variation in the study sample show a strong phylogenetic signal instead. Although extremely problematic for studying variation in fossil taxa at lower taxonomic levels, the cumulative effects of deformation in this study are shown to be random, and inclusion of deformed specimens in higher-level analyses of morphological disparity are warranted. Mean morphologies of distorted specimens are found to approximate the morphology of undistorted specimens, so we recommend use of species-level means in higher-level analyses when possible.
Physico-Chemical Analysis of Various Samples of Tomato Ketchup
Authors: N. Patil Pandurang , Moqbali Fatima H. Al , Rabaani Mizna A. Al , Ghaithi Nada A. Al
Published: October 2020

Aim of our present study was to analyze physico-chemical properties of tomato ketchup samples available in the local market. Major part of tomato consumption comes under processed products like tomato juice, ketchup and sauce. Recent studies have indicated the potential health benefits of a diet that are rich in tomatoes. Study of various physico-chemical parameter testing of four different types of tomato ketchup samples. Study was performed in Department of Applied Sciences, Chemistry section, University of Technology and Applied Sciences, Muscat, Oman during the September 2017 – April 2018. 

We have selected four different tomato ketchup samples from the local brand and tested for their various physical and chemical parameters such as, pH, conductivity, viscosity, solubility, acidity total, moisture, ash, vitamin C, sodium, potassium, calcium and magnesium. We have used routine and simple techniques for analysis. Such as some chemical methods, Flame photometer etc.  We have found that, pH was in the range of 3.6 – 3.8, conductivity 5.38 – 8.71 MS/cm, viscosity 3.93 – 6.76 Pa s, solubility 53.35 – 61.12, titratable acidity 3.2 – 4.01 g/100 gm, (pH metric 3.6 – 4.3 g/100 gm), ash 1.62 – 2.98%, vitamin C 17.25 – 55.23 mg/100 gm, sodium 294.5 – 475.85 ppm, potassium 93.5 – 153.3 ppm, magnesium 106 – 163 ppm, calcium 67 – 117 ppm. The result found in our analysis was more or less close to each other. On the basis of result obtained during the analysis of four tomato ketchup samples Jumbo sample was good amount of vitamin C, less ash value lowest sodium content.
Rural Women Involvement in Post-Harvest Rice Production Activities in Ekiti State, Nigeria
Authors: Okunlola J. O. , Ajileye A. , Owolabi O.
Published: October 2020

Women play important roles in food production most especially in the rural areas of Nigeria. The study therefore assessed the involvement of women in post-harvest rice production activities in Ekiti State, Nigeria. A well-structured interview schedule was used to collect primary data from one hundred and twenty (20) women who were rice farmers. The data collected were analyzed using descriptive statistics and inferential statistics. The study revealed that the mean age of the respondents was 41 years. Majority of the respondents were married (90.0%) with an average household size of 6persons. High cost of mechanical threshing machine ( 2.96) and inadequate finance ( 2.66) were the major constraints to respondents’ involvement in post-harvest rice production activities in the study area. The study recommends that women processors should form cooperative societies to procure combined harvesters, de-stoner, threshers and milling machines so as to reduce the drudgery involved in the processing of rice and rice processors should be given opportunity of financial assistance to procure essential storage equipment for their processing activities.
Effect of Fertigation on Yield, Fertilizer Use Efficiency and Economics in Hybrid Ridge Gourd
Authors: Murthy H. C. Ananda , Nair A. K. , Kalaivanan D. , Anjanappa M. , Hebbar S. Shankara , Laxman R. H.
Published: October 2020

A field Investigation was carried out to study the effect of fertigation on yield, fertilizer use efficiency and economics of hybrid ridge gourd [Luffa acutangula (L.) Roxb] Arka Vikram during 2018-2019 at Vegetable Research Block of ICAR- Indian Institute of Horticultural Research, Bengaluru, Karnataka. The experiment was laid out in randomized complete block design having eight treatments and three replications. The results of the experiment revealed   that   the  treatment  T3    i.e  application of water soluble  fertilizers @ 150:90:150  kg  NPK  ha-1 through fertigation recorded maximum number of female flower per vine (29.73), number of fruits per vine (19.68), fruit length (49.76 cm), fruit girth (18.40 cm), average fruit weight (454.03 g), fruit yield per vine (4.03 kg) and fruit yield per hectare (53.73 t). Application of water soluble fertilizers @ 150:90:150 kg NPK ha-1 through fertigation (T3) recorded significantly higher fruit yield per hectare (53.73 t ha-1), which was higher to the tune of 23.8 to 70.4 per cent than other treatments tested in hybrid ridge gourd. The second highest fruit yield was obtained with T2 (43.40 t ha-1) followed by T1 (42.10 t ha-1). However, T5 i.e application of water soluble fertilizers @ 50:30:50 kg NPK ha-1 resulted in highest fertilizer use efficiency (245.38 kg yield kg-NPK-1) compared to other treatments. Fertigation at 100% NPK dose along with mulching with silver-black plastic mulch gave the highest net income (Rs.555435.0 ha-1) and B: C ratio of 2.22.
Production and Characterization of Polyhydroxyalkanoates from Lactic Acid Bacteria Isolated from Dairy Wastewater, Fermented Cow Milk and ‘Ogi’
Authors: Monilola Wakil Sherifah , Makinde Oluwatobi Esther
Published: October 2020

Aims: This study aimed at screening, producing and characterizing polyhydroxyalkanoates (PHA) from lactic acid bacteria (LAB) isolated from dairy wastewater, fermented cow milk and “ogi”.

Place and Duration of Study: Department of Microbiology, Faculty of Science, University of Ibadan, Ibadan between August 2018 and February 2019.

Methodology: The initial screening of isolated LAB was carried out by Sudan Black staining method followed by secondary screening on liquid medium. Isolates that tested positive for Sudan Black stain and had the highest PHA yield from liquid medium was used for further analysis. The cell walls of selected isolates were lysed with sodium hypochlorite and PHA extracted using chloroform. Optimization of PHA production was carried out using different carbon and nitrogen sources, incubation temperature, pH and agitation speed. Extracted PHA was characterized by FTIR spectroscopy and the microstructure and surface morphology were observed using Scanning Electron Microscope.

Results: Seven isolates tested positive for Sudan Black stain of which two isolates identified as Lactobacillus plantarum CW10 and Lactobacillus casei WWD3 had the highest PHA yield from liquid medium. From the optimization experiment, highest PHA production was observed in Lactobacillus plantarum CW10 (20.5%) and Lactobacillus casei WWD3 (19.7%) when glucose and ammonium sulphate was used as carbon and nitrogen sources respectively, and at pH 6, agitation speed of 200 rpm and incubation temperature of 35oC and 40oC. The spectra of extracted PHA as characterized by FTIR showed absorption peaks for the carbonyl, C-H, -OH, aliphatic -CH3 and ester groups that are characteristics of PHA. The microstructure and surface morphology shows grains that are pseudo-spherical in shape with fairly regular distribution.

Conclusion: There is an appreciable production of PHA from the Lactobacillus strains and can be considered as part of the choice of organisms for PHA production in commercial quantity.
Preparation d'invertase insolubilisée par fixation sur bentonite
Authors: Monsan P. , Durand G.
Published: July 2002

Invertase was linked by means of a multi‐functional agent, cyanuric chloride to a clay, bentonite. Properties of insolubilized invertase were compared to free invertase and to invertase adsorbed on bentonite. Several enzyme have been insolubilized by coupling to bentonite using the method described in this paper.
Properties of a mutant lactose carrier of Escherichia coli with a Cys148 → Ser148 substitution
Authors: Neuhaus Jean-Marc , Soppa Jörg , Wright J.Keith , Riede Isolde , Blöcker Helmut , Frank Ronand , Overath Peter
Published: July 2002

The cysteine residue at position 148 in the lactose carrier protein of Escherichia coli has been replaced by serine using oligonucleotide‐directed, site‐specific mutagenesis of the lacY gene. The mutant carrier is incorporated into the cytoplasmic membrane to the same extent as the wild‐type carrier, confers a lactose‐positive phenotype on cells, and actively transports lactose and other galactosides. However, the maximum rate of transport for several substrates is reduced by a factor of 6–10 while the apparent affinity is reduced by a factor of 2–4. Carrier activity in the mutant is much less sensitive to sulfhydryl reagents (HgCl2, p‐(chloro‐mercuri)benzenesulfonate and N‐ethylmaleimide) than in the wild type, and β‐D‐galactosyl 1‐thio‐β‐D‐galactoside does not protect the mutant carrier against slow inactivation by N‐ethylmaleimide. It is concluded that the Cys148 residue is not essential for carrier‐catalyzed galactoside: proton symport and that its alkylation presumbly prohibits access of the substrate to the binding site by steric hindrance. A serine residue at position 148 in the amino acid sequence appears to alter the protein structure in such a way that one or more sulfhydryl groups elsewhere in the protein become accessible to alkylating agents thereby inhibiting transport. Recently, Trumble et al. [(1984) Biochem. Biophys. Res. Commun. 119, 860‐867] arrived at similar conclusions by investigating a mutant carrier with a Cys148→ Gly148 replacement.
Site‐selective cAMP analogs induce nuclear translocation of the RII cAMP receptor protein in Ha‐MuSV‐transformed NIH/3T3 cells
Authors: Clair Timothy , Ally Shamsia , Tagliaferri Pierosandro , Robins Roland K. , Sang Cho-Chung Yoon
Published: July 2002

Site‐selective cAMP analogs, depending on the position of their substituents on the adenine ring, selectively bind to either site 1 or site 2 of the known cAMP binding sites of protein kinase. Treatment of Harvey murine sarcoma virus‐transformed NIH/3T3 cells with such site‐selective analogs results in growth inhibition and phenotypic reversion, and the combination of a C‐8 thio or halogen analog (site 1 selective) with an N
6 analog (site 2 selective) produces a synergistic effect. We report here that the growth inhibitory effect of the analogs correlates with the nuclear translocation of the RII cAMP receptor protein, the regulatory subunit of protein kinase type it. The transformed NIH/3T3 cells contained no detectable level of RII in the nucleus, whereas nontransformed NIH/3T3 cells exhibited a high level of nuclear RII. Within 30 min after treatment of the transformed cells with the site‐selective analogs, immunofluorescence against the RII protein markedly increased in the cell nucleus. The nuclear translocation of the RII cAMP receptor protein is an early event in the reverse transformation of the fibroblasts treated with site‐selective cAMP analogs.
Photolabelling of a mitochondrially encoded subunit of NADH dehydrogenase with [3H]dihydrorotenone
Authors: Earley Fergus G.P. , Patel Salil D. , Ragan C.Ian , Attardi G.
Published: July 2002

Mitochondrial NADH dehydrogenase from bovine heart was photolabelled with the inhibitor [3H]dihydrorotenone. A constituent of the hydrophobic domain of the enzyme of M
r 33 000 was the major site of labelling. The identity of this protein with the mitochondrially encoded ND‐1 gene product was established by immunoblotting and immunoprecipitation with an antiserum raised to the expected C‐terminal sequence of the human ND‐1 gene product.
The importance of the phenyl‐tropolone ‘aS’ configuration in colchicine's binding to tubulin
Authors: Yeh Herman J.C. , Chrzanowska Maria , Brossi Arnold
Published: July 2002

Measuring ellipticities of (±)‐colchicine and (±)‐deacetamidocolchicine in the presence of tubulin afforded net positive CD bands with maxima at 340 nm resulting from reduction of the negative ellipticities upon binding of (−) enantiomers to the protein. Results of optical studies together with earlier NMR conformational analysis of these molecules substantiate the hypothesis that colchicinoids bind to tubulin with the phenyl‐tropolone moiety in the ‘aS’ configuration. Natural colchicine which binds to tubulin, therefore, should be referred to as (−)‐(aS, 7S)‐colchicine.
Stereospecific assignment of the methyl 1H NMR lines of valine and leucine in polypeptides by nonrandom 13C labelling
Authors: Senn H. , Werner B. , Messerle B.A. , Weber C. , Traber R. , Wüthrich K.
Published: July 2002

An alternative method for the stereospecific assignment of the methyl groups of valine and leucine in the nuclear magnetic resonance (NMR) spectra of peptides and proteins is proposed, and its practical application is demonstrated with the assignment of all valine and leucine methyl groups in cyclosporin A. The method is based on the use of a mixture of fully 13C‐labelled and unlabelled glucose as the sole carbon source for the biosynthetic production of the polypeptide studied, knowledge of the independently established stereoselectivity of the reaction pathways of valine and leucine biosynthesis, and analysis of the distribution of 13C labels in the valyl and leucyl residues of the product by two‐dimensional heteronuclear NMR correlation experiments.
Kidney fatty acid‐binding protein: Identification as α2U‐globulin
Authors: Kimura Hideka , Odani Shoji , Suzuki Jun-ichi , Arakawa Masaai , Ono Teruo
Published: July 2002

A fatty acid‐binding protein was purified from male rat kidney by the method of Fujii et al. [(1987) Arch. Biochem. Biophys. 254, 552–558]. Based on the close similarity of amino acid composition and the identity of the amino acid sequence in the amino‐terminal region, the fatty acid‐binding protein was identified as α2U‐globulin, which is the major male‐specific protein in rat urine. The amino‐terminal residue of the isolated kidney protein corresponds to residue 10 of α2U‐globulin, suggesting that the protein has been proteolytically processed in the kidney. This fatty acid‐binding protein could not be immunologically detected in female rat kidney.
Sensitivity of the retinal circular dichroism of bacteriorhodopsin to the mutagenetic single substitution of amino acids: tyrosine
Authors: Du-Jeon-Jang  , El-Sayed M.A. , Stern Lawrence J. , Mogi Tatsushi , Gobind Khorana H.
Published: July 2002

Bacteriorhodopsin (bR) in the native purple membrane, in wild type expressed in E. coli and reconstituted in lipid vesicles, and its constituted mutants with substitutions of Tyr‐185 by Phe all are found to have different visible retinal CD spectra. The results strongly suggest that the environment of the retinal in bR determines the sign and heterogeneity of its visible retinal CD spectrum. This supports the recent proposal that the observed biphasic CD spectrum of bR is due to the superposition of the CD spectra having opposite signs of more than one type of bR rather than due to exciton coupling.
Molecular conformation of achatin‐I, an endogenous neuropeptide containing D‐amino acid residue
Authors: Kamatani Yoshimi , Minakata Hiroyuki , Iwashita Takashi , Nomoto Kyosuke , In Yasuko , Doi Mitsunobu , Ishida Toshimasa
Published: July 2002

The molecular conformation of achatin‐I neutral form (H‐Gly‐D‐Phe‐Ala‐Asp‐OH), an endogenous neuropeptide, was elucidated by X‐ray crystal analysis. The molecule has a type II' β‐turn structure with the D‐Phe‐Ala residues at the corner of the bend, which is further stabilized by two NH(Gly)βCγ=Oδ(Asp) and NH(Asp)βCγ=Oδ(Asp) intramolecular hydrogen bonds. This turn conformation may be an important feature of achatin‐I related to its neuroexcitatory activity.
Intramitochondrial formation of oxidized glutathione during the oxidation of benzylamine by monoamine oxidase
Authors: Werner Peter , Cohen Gerald
Published: July 2002

Oxidation of benzylamine by MAO results in an accumulation of GSSG in mouse liver mitochondria. Formation of GSSG is prevented by deprenyl, an inhibitor of MAO‐B, but not by catalase. GSSG accumulation also occurs with dopamine as substrate. Oxidation of monoamines by mitochondrial MAO represents a potential oxidant stress for mitochondria.
Troponin I and caldesmon restrict alterations in actin structure occurring on binding of myosin subfragment I
Authors: Nowak Ewa , Borovikov Yurii S. , Khoroshev Mikhail I. , Dabrowska Renata
Published: July 2002

The effect of troponin I and caldesmon on phalloidin‐rhodamine‐ and 1,5‐IAEDANS‐labelled actin in skeletal muscle ghost fibers was investigated by polarized fluorescence. Both these proteins inhibited the structural alterations in the actin monomer and the increase of flexibility of actin filaments occurring on binding of myosin heads, and their effects were potentiated by tropomyosin. This immobilization of the actin filament through troponin I and caldesmon seems to originate from restriction of the relative motions of the two domains within the monomer.
Identification and immunohistochemical mapping of GABAA receptor subtypes containing the δ‐subunit in rat brain
Authors: Benke D. , Mertens S. , Trzeciak A. , Gillessen D. , Mohler H.
Published: July 2002

Synaptic inhibition in brain is mainly mediated via GABAA receptors which display a striking structural heterogeneity. A novel type of GABAA receptor subunit, the δ‐subunit, has recently been described based on molecular cloning of its cDNA [1]. To identify the prevalence and distrubution of GABAA receptors which contain the δ‐subunit protein in situ, polyclonal site‐directed antisera were developed against three synthetic peptides derived form the rat δ‐subunit cDNA‐sequence. All antisera specifically recognized a 54 kDa protein in GABAA receptor preparation. Nearly 30% of the GABAA receptors contained the δ‐subunit immunoreactivity and displayed high affinity GABA and high affinity benzodiazepine binding sites as shown by immunoprecipitation. Receptors which contain the δ‐subunit were immunohistochemically shown to be restricted to a few brain areas such as the cerebellum, thalamus and dentate gyrus of the hippocampal formation. Thus, those neurons which express GABAA receptors with a δ‐subunit have now been visualized and made accessible for a functional analysis of this GABAA receptors subtype in situ.
Codon bias and gene expression
Authors: Kurland C.G.
Published: July 2002

The frequencies with which individual synonymous codons are used to code their cognate amino acids is quite variable from genome to genome and within genomes, from gene to gene. One particularly well documented codon bias is that associated with highly expressed genes in bacteria as well as in yeast; this is the so‐called major codon bias. Here, it is suggested that the major codon bias is not an arrangement for regulating individual gene expression. Instead, the data suggest that this codon bias, which is correlated with a corresponding bias of tRNA abundance, is a global arrangement for optimizing the growth efficiency of cells. On the practical side, it is suggested that heterologous gene expression is not as sensitive to codon bias as previously thought, but that it is quite sensitive to other characteristics of the heterologous gene.
Low resolution solution structure of the Bacillus subtilis glucose permease IIA domain derived from heteronuclear three‐dimensional NMR spectroscopy
Authors: Fairbrother Wayne J. , Gippert Garry P. , Reizer Jonathan , Saier Milton H. , Wright Peter E.
Published: July 2002

A low resolution solution structure of the IIA domain of the Bacillus subtilis phosphoenolpyruvate‐sugar phosphotransferase system (PTS) glucose permease has been determined using 945 inter‐residue and 724 intra‐residue distance constraints derived from three‐dimensional 15N and 13C edited NOESY spectra. A total of 15 structures was generated using distance geometry calculations. The protein is comprised of 13 β‐strands forming an antiparallel β‐barrel, The average backbone atomic RMS deviation about the average distance geometry structure for the β‐sheet residues is 1.1 Å. The conformations of the loop regions between the β‐strands are less well determined. Backbone distance constraints obtained during the process of sequential assignment were insufficient to correctly calculate the polypeptide fold.
DNA intervention in transcriptional activation
Authors: Bhargava Purnima , Chatterji Dipankar
Published: July 2002

Accurate initiation of eukaryotic mRNA synthesis takes place as a result of the interplay between general transcription factors and RNA polymerase II. Activation of transcription from the basal level involves a number of promoter‐specific trans‐acting factors which interact with cis elements in the promoter DNA. In this paper we have emphasized the importance of even those portions of the promoter stretch which do not have any identifiable binding sites for regulatory proteins. The length and structure of the DNA between cognate binding sites of trans‐acting factors may interfere with the level of transcriptional activation. Depending upon the length of the intervening DNA we describe three cases of transcriptional activation. In addition, based on this classification we propose a new third domain, the other two being DNA binding and transcriptional activation domains, which is involved in bending the intervening DNA so that activation from a distance can take place successfully.
Phorbol esters induce nitric oxide synthase and increase arginine influx in cultured peritoneal macrophages
Authors: Hortelano Sonsoles , Genaro Ana M. , Boscá Lisardo
Published: July 2002

Incubation of peritoneal macrophages with β‐phorbol 12,13‐dibutyrate promotes a time‐dependent release of NO to the incubation medium. This effect was antagonized by LPS, a well known inducer of nitric oxide synthase (NOS) expression in macrophages, and was inhibited by N
G‐methyl‐l‐arginine and N
ω‐nitro‐l‐arginine. An increase in intracellular cGMP and NOS activity was observed in parallel with NO release. The induction of NOS was accompanied by a stimulation of arginine influx within the cell. These results suggest that activation of protein kinase C by phorbol esters is sufficient to promote NOS induction in macrophages.
Two‐step epoxidation of hyoscyamine to scopolamine is catalyzed by bifunctional hyoscyamine 6β‐hydroxylase
Authors: Hashimoto Takashi , Matsuda Jun , Yamada Yasuyuki
Published: July 2002

In several solanaceous plants, hyoscyamine is first hydroxylated at the 6β‐position, and then epoxidized to scopolamine. We expressed hyoscyamine 6β‐hydroxylase (H6H) in Escherichia coli as a fusion protein with maltose‐binding protein. The crude cell extract from the bacterium that expressed the soluble fusion protein showed a strong hydroxylase activity and a weak epoxidase activity. When 100 μM of hyoscyamine was fed to the recombinant bacterium, the alkaloid was first converted to 6β‐hydroxyhyoscyamine, and then to scopolamine, which was almost the only alkaloid found in the culture after one week. Therefore, H6H catalyzes two consecutive reactions that oxidize hyoscyamine to scopolamine.
Molecular weight‐determination of biosynthetically modified monomeric and oligomeric muropeptides from Escherichia coli by plasma desorption‐mass spectrometry
Authors: Caparrós Marta , Pittenauer Ernst , Schmid Erich R. , de Pedro Miguel A. , Allmaier Günter
Published: July 2002

The presence of certain d‐amino acids in the growth media of Escherichia coli results in the accumulation of 2 major and 3–5 minor new muropeptides in the murein sacculus. Preliminary data suggested that the major muropeptides correspond to a monomer and a cross‐linked dimer with one residue of d‐amino acid per molecule. We have analyzed several d‐amino acid‐modified muropeptides by plasma desorption‐mass spectrometry. Our results confirmed that the general structures of the major modified muropeptides are: GlucNAc‐MurNAc‐l‐Ala‐d‐Glu‐m‐A2pm‐d‐X, and GlucNAc‐MurNAc‐l‐Ala‐d‐Glu‐m‐A2pm‐d‐Ala; GlucNAc‐MurNAc‐l‐Ala‐d‐Glu‐m‐A2pm‐d‐X, being X a residue of the d‐amino acid. These results corroborate the usefulness of this technique for the structural analysis of muropeptides.
Is thermotolerance of yeast dependent on trehalose accumulation?
Authors: Nwaka Solomon , Kopp Meinrad , Burgert Markus , Deuchler Inge , Kienle Iris , Holzer Helmut
Published: July 2002

During heat stress, trehalose concentration increases in yeast cells in parallel to thermotolerance. This parallelism suggested that trehalose mediated thermotolerance. We show in this work that, under certain conditions, trehalose accumulation and increase in thermotolerance do not go in parallel. A mutant deficient in the trehalose‐degrading neutral trehalase shows, after shift from 40°C to 30°C, low thermotolerance in spite of a high trehalose concentration. When glucose is added to stationary yeast cells with high trehalose concentration and high thermotolerance, trehalose concentration decreases while thermotolerance remains high. A mutant deficient in ubiquitin‐conjugating genes, ubc4ubc5, shows during exponential growth a low trehalose concentration, but a high thermotolerance, in contrast to wild‐type cells. Because the ubc4ubc5 mutant synthesizes heat‐shock proteins constitutively, it is proposed that, under these conditions, accumulation of heat‐shock proteins, and not trehalase, mediates thermotolerance.
Cloning of a Xenopus laevis muscarinic receptor encoded by an intronless gene
Authors: Herrera Luisa , Carvallo Pilar , Antonelli Marcelo , Olate Juan
Published: July 2002

The Xenopus laevis oocyte has endogenous sites that bind muscarinic agonists, which have been pharmacologically characterized as M3 and/or M1 receptor subtypes. In order to define the molecular identity of the receptor protein we have analyzed a Xenopus oocyte cDNA library and cloned a 2.9 kb cDNA fragment encoding a muscarinic receptor (xMR). The deduced amino acid sequence reveals a protein of 484 residues with an apparent molecular weight of 54,188 Da. Amino acid comparison with previously cloned mammalian muscarinic receptors showed a 78% identity with the human m4 subtype, presenting at the same time clustered differences within the amino‐terminal region and third intracellular loop. Genomic Southern analysis displayed the presence of one main gene belonging to this subtype, and the PCR analysis revealed an intronless gene.
Dephosphorylation of microtubule‐associated protein tau by protein phosphatase‐1 and ‐2C and its implication in Alzheimer disease
Authors: Gong Cheng-Xin , Grundke-Iqbal Inge , Damuni Zahi , Iqbal Khalid
Published: July 2002

Microtubule‐associated protein tau is abnormally hyperphosphorylated and forms the major protein subunit of paired helical filaments (PHF) in Alzheimer disease brains. The abnormally phosphorylated sites Ser‐199, Ser‐202, Ser‐396 and Ser‐404 but not Ser‐46 and Ser‐235 of Alzheimer tau were found to be dephosphorylated by protein phosphatase‐1 and this dephosphorylation was activated by Mn2+. In contrast, protein phosphatase‐2C did not dephosphorylate any of these sites. Both protein phosphatase‐1 and ‐2C had high activities towards [32P]tau phosphorylated by cAMPdependent protein kinase. These results suggest that both protein phosphatase‐1 and ‐2C might be associated with normal phosphorylation state of tau, but only the former and not the latter phosphatase is involved in its abnormal phosphorylation in Alzheimer disease.
An oocytic membrane receptor for biotin‐binding protein
Authors: Vieira Amandio V. , White Harold B. , Vieira Päivi M.
Published: July 2002

The chicken oocyte accumulates a biotin‐binding protein (BBP) in the yolk that is distinct from the avidin in the ‘egg white’. An identical BBP to that of yolk is also present in the circulation of the laying hen. We report the first evidence for the existence of a BBP receptor in the oocyte vitelline membrane. Reduction of the 100 kDa receptor results in loss of BBP‐binding activity; this suggests that a disulfide‐bonded region of the receptor is necessary for maintaining BBP‐binding activity. We show further that the levels of serum BBP are strictly dependent on the presence of estrogen. As expected, BBP is not detected in significant quantities in rooster serum. Thus, these results suggest that circulatory BBP, like other estrogen‐dependent components of serum, has a cognate binding activity on the oocyte membrane that may mediate its endocytosis.
Enhancement of nucleocytoplasmic export of HTLV‐1 Rex mRNA through cis and trans interactions of the mRNA with the complex of Rex protein and Rex‐responsive element
Authors: Fu Litao , White Kenneth N.
Published: July 2002

p27 rex of HTLV‐1 promotes nucleocytoplasmic export of viral mRNAs through binding of the Rex‐response element (RexRE) present at the 3′ end of the viral transcripts in cis with respect to the ORFs of the viral mRNAs. We have found that expression of the RexRE in trans, as a separate RNA, still allows Rex protein to promote export of viral mRNAs lacking the RexRE. The data suggest the formation of a ternary complex between Rex protein, RexRE and upstream elements of viral mRNA and hence the existence of secondary sites of interaction between Rex protein and viral RNAs.
Neuropathogenic actions of cytokines assessed in transgenic mice
Authors: Campbell Iain L.
Published: July 2002

Cytokines are potent biological response modifiers that exhibit a spectrum of cellular actions. These factors have been implicated as important mediators of physiologic and possibly pathophysiologic processes within the CNS. Targeting the expression of cytokines to specific tissues in transgenic mice has provided a powerful approach to the investigation of complex cellular responses at a localized level and also recapitulated more closely the expression of these mediators as found in pathogenetic processes. This review will focus on the recent application of transgenic technology to achieve the specific cerebral expression of cytokines. The targeting of cytokine gene expression to astrocytes in transgenic mice has provided new and dramatic insights into the CNS pathobiology of these host‐response molecules. Specifically: (1) transgenic expression of the cytokines IL‐6, IL‐3 and IFN‐α in the CNS results in the development of acute (high expression) or chronic progressive (low expression) CNS disease associated with a spectrum of clinical, physiologic and pathologic manifestations; (2) although the clinical, cellular and molecular phenotype produced by the cerebral expression of the various cytokines showed some overlap, the differences were more prominent reflecting the unique actions of each cytokine; (3) these transgenic models which recapitulate many of the structural and functional impairments seen in human neurodegenerative diseases, highlight the point that cytokines, which normally function as primary regulators of the host response, also have the potential to mediate significant injury in the CNS. Therefore, these transgenic models have provided a valuable tool for adbancing our understanding of the CNS pathobiology of cytokines and will no doubt offer a unique resource for the development and testing of therapies aimed at abrogating the toxic actions of these important mediators.
Pentobarbital modulatory effect on GABA binding sites in developing chick optic lobe
Authors: de Plazas S. Fiszer , Viapiano M.S. , de Novara A. Mitridate
Published: July 2002

Barbiturates are allosteric modulators of the CNS GABAA receptor, increasing [3H]‐GABA binding to its receptor sites. In the present work we have studied the modulatory effect of the barbiturate pentobarbital on low‐affinity GABA binding sites during ontogenetic development of the chick optic lobe. Our results indicate that [3H]‐GABA binding enhancement by pentobarbital shows a differential profile during development, following a two‐component enhancement model at early stages of development and a single‐component enhancement model in the adult stage. Kinetic analysis performed at different stages of development showed that barbiturate enhancement was invariably due to an increase in [3H]‐GABA binding affinity, while maximal binding capacity remained unchanged. Using GABA antagonists, picrotoxinin and bicuculline, convulsant sensitivity of high‐affinity barbiturate modulatory sites was found at early stages.

These data suggest that barbiturate action displays receptor heterogeneity during development, with high‐ and low‐affinity modulatory sites only at early stages, while the high‐affinity sites disappear between hatching and adulthood. Kinetic data indicate that both barbiturate modulatory sites are coupled to the GABAA receptor at early stages. The presence of high‐affinity modulatory sites at early stages and at hatching suggests a major role during visual pathway maturation.
In vitro induction of apoptosis of developing brain cells by 5‐azacytidine
Authors: Hossain M.M. , Nakayama H. , Goto N.
Published: July 2002

We had found that 5‐azacytidine (5Az), a cytidine analogue, could produce apoptosis of fetal developing neuronal cells on the day after injection of the agent into dams by the i.p. route at 11 days of gestation. To make a further understanding of the phenomenon by comparing the results between the in‐vivo and in‐vitro system, this study was carried out. Entire cephalic parts of the fetuses were collected aseptically at days 11 of gestation and a mixed culture, consisting of neuronal and mesenchymal cells, was established after one week of incubation. The silver‐staining revealed pyknotic nuclei and loss of dendrites of neuronal cells in the lower (5 μg/ml) dose of the 5 Az‐added group. SEM showed shrinkage of the cell body and blebbing formation on the cell surface. TEM evoked margination, segmentation and complete condensation of the nuclear chromatin. Scattered positive signals identical to the apoptotic cells and aggregated fragmented DNA were detected by the TUNEL method. Treatment of higher doses of 5Az (50 and 500 μg/ml), however, induced necrosis of both neuronal and mesenchymal cells, light‐ and electron‐microscopically. On the contrary, the control group (0 μg/ml) showed normal development of neuronal cells and very few positive signals of physiological apoptosis. It was concluded that 5Az could induce apoptosis of developing neuronal cells at lower doses, but necrosis of a wider cell population at higher doses. Involvement of hypomethylation, an important biochemical function of 5Az, in apoptosis was also speculated.