bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Knowledge of MDR-TB among Medicine Training Doctors in Tertiary Care Hospital, Karachi, Pakistan
Authors: Saulat Afifa , Jafri Anwar Nabeel
Published: September 2020

Tuberculosis is the oldest documented infectious diseases in humans and they still cause significant morbidity and mortality. Multi-Drug Resistant Tuberculosis (MDR-TB) is a growing hazard to human health worldwide and threat to control of tuberculosis. WHO estimates 3.2% incidence of MDR TB in new cases. MDR-TB new cases are created each year by a combination of poor patient compliance with treatment and physician error. The purpose of the study is to determine the status of knowledge and awareness amongst the medicine resident about the very basic knowledge of MDR-TB and need to strengthen teaching about tuberculosis to postgraduates so the objective of the study is to determine the frequency of knowledge of MDR –TB among medicine residents (postgraduate trainees) at a tertiary health care hospital Karachi. It is a descriptive based cross sectional study. 58 post graduates trainees were included. A simple questionnaire about MDR-TB was asked to fill in 30 minutes, each correct response will be given 10 marks and those who score 70% will be labeled as knowledgeable. The primary outcome measure was the frequency of knowledge of MDR –TB among medicine residents (postgraduate trainees) at a tertiary health care which turned out to be 65.5% knowledge among postgraduate trainees. So we concluded that there is a need of further studies with larger sample size and follow up studies after educating the trainees more of senior levels so that identification of predictors of mortality, so as to timely diagnose, intervene and hence prevent morbidity and fatalities. It is, therefore, important to develop continuous health education to improve TB knowledge and awareness at different levels.
Comparative Study of the Cranio-osteology of Two Lonchophyllinae from Colombia
Authors: Casanova P. M. Parés-
Published: September 2020

Lonchophyllinae comprises four genera of Neotropical nectarivorous bats. Inside this subfamily       the genus Lonchophylla is one of the most diverse. A total of 51 Lonchophylla skulls from       Colombia (L. robusta n=34 and L. thomasi n=17) was studied by means of geometric morphometric methods with the aim to determine their morphological differential characteristics. For this purpose, viscero and neurocranium were evaluated with 12 landmarks on the dorsal aspect of left hemicranium. The two species were statistically different according to size (expressed as skull length) but also to shape (expressed as the set of Procrustes coordinates). Skulls in L. robusta were clearly bigger, with shorter braincase and longer rostra, and their zygomatic process was more latero-caudally displaced, whereas L. thomasi presented a zygomatic process which was        displaced more rostrally as well longer braincases. All these detected skull form dissimilarities between both species would be explained by their different alimentary habits, but a combination of dietary analysis and morphological analysis is needed to make stronger inference about diet preferences.
Efficiency and Response to Nitrogen Use in Maize Genotypes for Silage Production in Tropical Climate
Authors: Santos Weder Ferreira dos , Junior Osvaldo José Ferreira , Maciel Lucas Carneiro , Peluzio Joênes Mucci , Afférri Flávio Sérgio , Sodré Layanni Ferreira , Faria Lucas Alves de , Vieira Lucas Sodré , Barbosa Adriano Silveira , Silva Rafael Marcelino da
Published: September 2020

Aims: This study aimed to select efficient and responsive maize genotypes to the use of nitrogen for silage.

Study Design: The experimental design was randomized blocks in a 2 x 11 factorial scheme, the first factor being two nitrogen levels: 165 kg ha-1 of N and 15 kg ha-1 of N, and second factor eleven maize genotypes: BRS 3046, M 274, AG 8088PRO2, ANHEMBI, PR 27D28, AG 1051, P33-16, P33-11, P29-M12, P36-19, and P40-8.

Place and Duration of Study: The experiment was carried out in the 2017/18 harvest at Sítio Vitória (8º18'32" S, 50º36'58" W), located in the municipality of Santa Maria das Barreiras, southern region of Pará state, Brazil.

Methodology: Sowing fertilization was performed in the furrow with 300 kg ha-1 of NPK 5-25-15. Topdressing nitrogen fertilization was performed only at high N, having as source urea (45% N) at a dose of 150 kg ha-1 of N. Parceled in stages V4 and V8. The shoot fresh mass was evaluated at stages R4 and R5, with the cut performed 20 cm from the soil.

Results: The highest shoots fresh masses were obtained in treatments with high use of N, with a general mean of 628 g plant-1. The mean response of 1.87 g of plants per kg of N applied. Genotypes M 274, AG 8088PRO2, PR 27D28, AG 1051 and P 36-19 were efficient to use N. Genotypes AG 8088PRO2, PR 27D28, P29-M12, and P 36-19 were classified as responsive to N application.

Conclusion: Genotypes AG 8088PRO2, PR 27D28 and P36-19 were efficient in use and responsive to nitrogen application. And they are recommended for cultivation with low and high technological level.
Influence of Number of Suckers in Ratoon Crop on Yield and Quality of Malbhog (AAB) Banana
Authors: Borah Rupshree , Hazarika D. N. , Langthasa Supriya , Das Hemanga
Published: September 2020

An experiment was carried out at instructional cum experimental farm, Department of Horticulture, Biswanath College of Agriculture, Assam Agricultural University, Biswanath Chariali to study the effect of number of suckers per hill on yield and quality of banana cv. Malbhog (AAB) in ratoon crop by maintaining different numbers of suckers per hill as-T1 (one sucker per hill), T2 (two suckers per hill), T3 (three suckers per hill), and T4 (four suckers per hill). Plants for each treatment were planted in two spacing as S1 (2.1 m x 2.1 m) and S2 (2.5 m x 2.5 m). One treatment with recommended package of practice (one sucker retain with mother plant at shooting) was also included in the experiment as control. The treatment combinations were laid out in factorial Randomized Block Design with three replications. Finger length (15.22 cm), finger girth (12.05 cm), finger volume (84.44cc) and finger weight (83.65 g), number of fingers (92.75/bunch), hands (7.27/bunch), bunch weight (9.41 kg/bunch and yield (15.05 t/ha), were highest in S2T1 (2 suckers per hill in 2.5 m x 2.5 m spacing). Lowest duration from harvesting of first crop to harvesting of first ratoon crop (68.50 days) observed in S2T1. Yield of banana was significantly lower in wider spacing of 2.5 m x 2.5 m (S2) than S1 (2.1 m x 2.1 m). There was no significant effect on quality attributing parameters of fingers.
Determination of Nutrient Content, in vitro Digestibilities, Anti-Nutrients, Β-Carotene and Total Antioxidant Activity of Sesame (Sesamum indicum)
Authors: Bansal Tanvi , Kawatra Asha
Published: September 2020

Sesame (Sesamum indicum) is one of the valuable vegetarian sources of dietary protein with good quality amino acids that are very essential for growth. It possesses phytonutrients such as omega-6 fatty acids, flavonoids, antioxidants, and certain vitamins with potential anti-cancerous as well as health-promoting properties. Sesame seeds were analyzed for various nutritional parameters. The amount of moisture, protein, fat, ash, and fibre were found to be 4.17, 21.18, 46.64, 4.62, and 3.06 percent, respectively whereas calcium, iron, and zinc were 1294, 15.37, and 7.74 mg/100g, respectively.  In vitro protein digestibility was estimated to be 79.50% whereas phytic acid was 247.37 mg/100g, and polyphenols 189.30 mg/100g.The values for β-Carotene and total antioxidant activity (TAA) was found to be 12.75 μg/100g and 0.94 mg/g, respectively. Looking at the good nutritional profile of sesame, it can be utilized in various supplementary food products to enhance the product quality by improving its taste and increasing its energy, protein, calcium, and mineral content. Incorporation of sesame seeds into daily food items can make them both micro and macro nutrient-dense, which can be used for feeding people from all the age-groups. And also, the information provided may help plant breeders to develop improved varieties of sesame in the future.
Thermal Power Station and Human Health in an Agriculturally Green Ecology: The Impact and Perception
Authors: Quader Sk Wasaful , Ghosh Arindam , Acharya S. K. , Haque Monirul , Mondal Kabita , Biswas Amitava
Published: September 2020

Thermal power stations are now considered as the foremost global concern as these are responsible to produce detrimental effects on the environment. Environmental Impact Assessment (EIA) is a process of evaluating the likely environmental impact so proposed project or development, taking into account inter-related socio-economic, cultural and human-health impacts, both beneficial and adverse. In this study, the perception of certain(60) farmers in 5 villages of Kolaghat block of Purba Medinipur,West Bengal, India are recorded and analyzed on the basis of their knowledge and views about thermal power, environment and about their individual enterprises. There are 10 independent variables-ages (x1), education (x2), family Member (x3), income (x4), homestead land (x5), total Land (x6), land under Boroj (x7), input cost (x8), and livestock number (x9), distance of villages from Kolaghat thermal power plant (x10) and 1 dependable variables- 1) perceived impacts of Kolaghat thermal power plant on human health(y1).It has been found that toxic elements and fly ash from Kolaghat thermal power plant have several consequences upon local environment, human, agriculture and livestock. It has also revealed that Kolaghat thermal power plant hampers the social ecology of the local areas. The study has further suggested several recommendations to cope with adverse environmental and ecological condition.
Determining Appropriate Fertilizer Scheme for Maize and Sorghum Cultivation in the Sahel Agroecological Zone of Cameroon
Authors: Temegne Nono Carine , Ngome Francis Ajebesone , Suh Christopher , Youri Alphonse , Basga Simon Bjakba
Published: September 2020

The objective of this study was to investigate appropriate fertilization schemes to improve the production of maize and sorghum in the Sahel agroecological zone of Cameroon. The experiment was carried out in 2018 at IRAD (Institute of Agricultural Research for Development) Kismatari experimental field. The experimental setup was a complete randomized block design in four replicates and four treatments for each crop. For maize, treatments were: T1 (No input), T2 (100 kg NPK + 100 kg Urea.ha-1), T3 (150 kg NPK + 150 kg Urea.ha-1), and T4 (200 kg NPK + 200 kg Urea.ha-1). For sorghum, treatments were: T1 (No input), T2 (50 kg NPK + 50 kg Urea.ha-1), T3 (100 kg NPK + 100 kg Urea.ha-1), and T4 (150 kg NPK + 150 kg Urea.ha-1). All fertilizer treatments NPK and urea were applied to both crops respectively at 3 and 5 weeks after sowing. Nine weeks after sowing, the plant height was highest at T3, following by T2 and T4 for the two crops. The treatment T1 exhibited the lowest grain yield while T2 and T3 showed intermediate grain yield. The treatment T4 produced the highest biomass, number of ears.plant-1, and grain yield (maize: 3.3 t. ha-1, sorghum: 2.9 t.ha-1) for the two crops and thus appears to be the most appropriate fertilizer recommendation for maize and sorghum production in the Sahel zone. However, costs-benefits studies for the use of fertilizer NPK and urea are warranted to facilitate adoption by farmers in the agroecological zone.
PENGARUH RELATED PARTY TRANSACTION TERHADAP NILAI PERUSAHAAN
Authors: Anggala Alan , Basana Sautma Ronni
Published: September 2020

Peneltian ini bertujuan untuk menguji pengaruh related party transction terhadap nilai perusahaan dengan dan tanpa menggunakan variabel kontrol. Variabel related party transaction diukur dengan sales of related party transaction (SRPT), purchase of related party transaction (PRPT), account receivable of related party transaction (ARRPT), dan account payable of related party transaction (APRPT). Variabel kontrol terdiri dari ukuran perusahaan dan corporate governance, sedangkan variabel dependen adalah nilai perusahaan yang diukur dengan menggunakan Tobin's Q. Sampel penelitian adalah perusahaan manufaktur yang terdaftar di Bursa Efek Indonesia (BEI) pada periode penelitian 2010-2017. Sampel dipilih dengan menggunakan metode purposive sampling dan diperoleh sebanyak 42 perusahaan untuk dijadikan sampel. Penelitian ini menggunakan metode regresi data panel. Hasil peneltian menunjukkan SRPT, PRPT, ARRPT, APRPT tidak berpengaruh signifikan terhadap nilai perusahaan tanpa dan dengan menggunakan variabel kontrol.
Contributions of the theory of the peaceful end of life to the nursing care for patients under palliative care
Authors: Zaccara Ana Aline Lacet , Batista Patricia Serpa de Souza , Vasconcelos Monica Ferreira de , Dias Kalina Coeli Costa de Oliveira , Aguiar Pamella Kelly Farias de , Costa Solange Fátima Geraldo da
Published: September 2020

Objetivo:Investigar as contribuições da Teoria Final de Vida Pacífico para a assistência de enfermagem ao paciente em Cuidados Paliativos.Método: Pesquisa de campo com abordagem qualitativa, na qual participaram 12 enfermeiros. Para a coleta dos dados utilizou-se a técnica de entrevista semiestruturada. Os dados foram analisados mediante a técnica de análise de conteúdo. Resultados:Da análise do material empírico, emergiram duas categorias: Espiritualidade na promoção de paz nos momentos finais; Atender aos desejos do doente terminal como atitude de respeito à sua dignidade. Conclusão: As principais contribuições da Teoria do Final de Vida Pacífico consistem em fornecer um suporte apropriado para nortear as estratégias utilizadas por enfermeiros, especialmente no que se refere a promoção de paz mediante a atenção a dimensão espiritual e o respeito à dignidade do paciente em fase final de vida relacionada ao atendimento aos últimos desejos do paciente e a solução de situações mal resolvidas.
Stoichiometry of GTP hydrolysis in a poly(U)‐dependent cell‐free translation system
Authors: Gavrilova L.P. , Kakhniashvili D.G. , Smailov S.K.
Published: July 2002

The Stoichiometry of GTP hydrolysis during peptide elongation in the processes of codon‐specific translation and misreading of polyuridylic acid was determined in a cell‐free system in which all ribosomes were active in peptide synthesis. Ribosomes carrying oligophenylalanine presynthesized on poly(U) covalently bound to Sepharose were used. In the codon‐specific translation of poly(Phe) on poly(U)‐Sepharose at optimal Mg2+ concentration (6 mM MgCl2), the ratio of GTP cleaved to Phe polymerized was found to be about 2 (+‐ 0.1). Under the same conditions but during misreading (elongation of polyleucine on poly(U)‐Sepharose) the GTP/Leu ratio increased 10 times (from 16 to 25 in different experiments).
Calcitonin mRNA activity in young obese (fa/fa) Zucker rats
Authors: Segond N. , Jullienne A. , Tahri E.H. , Garel J.-M.
Published: July 2002

Alterations in both calcitonin (CT) secretion and plasma calcium were recently described in adult obese Zucker rats. We have investigated the CT biosynthetic activity of thyroid glands in 30‐day‐old obese Zucker rats (fa/fa), and their controls (Lean). Plasma calcium level was significantly increased (+0.6) in obese animals, but plasma phosphate was unchanged. Plasma CT levels measured by radioimmunoassay (RIA) were significantly decreased in fatty (0.50 ± 0.03 vs 0.68 ± 0.03 in Leans; P < 0.001), but thyroidal hormone content was not different between Lean and fatty rats (68.7 ± 5.1 in Leans vs 60.5 ± 3.6 in fatty rats). mRNA was extracted from 10 thyroids, and translated in a rabbit reticulocyte lysate (NEN) in the presence of [35S]methionine. After polyacrylamide gel electrophoresis, specific immunoprecipitates were autoradiographied and quantified by integration. A 50% decrease in translatable CT mRNA was observed in fatty rats. In basal conditions, the biosynthetic activity of C cells in obese rats correlates with the secretion rate of the hormone in the face of unchanged thyroidal CT contents.
Alanine and lactate as gluconeogenic substrates during late gestation
Authors: Cuezva J.M. , Valcarce C. , Chamorro M. , Franco A. , Mayor F.
Published: July 2002

Rates of alanine incorporation into glucose by isolated liver cells of fed rats are 5‐fold higher than those observed when lactate was used as substrate. The rates of gluconeogenesis from alanine and lactate in isolated liver cells of fed pregnant rats increase 50 and 200–400%, respectively, over virgins during the last 3 days of gestation. The results support the existence of an increase in the alanine‐glucose cycle in the late pregnancy as an important homeostatic pathway in the supply of glucose to the growing fetus.
Stoichiometry of sodium‐ and chloride‐coupled glycine transport in synaptic plasma membrane vesicles derived from rat brain
Authors: Aragón M.Carmen , Giménez Cecilio , Mayor Federico
Published: July 2002

The stoichiometric properties of the glycine transporter were studied in synaptic plasma membrane vesicles from rat brain. The present results, together with previous data from our laboratory, allow us to suggest a Stoichiometry of 2 Na+ and 1 Cl− per glycine zwitterion for the translocation cycle catalyzed by the glycine carrier. We propose a kinetic model with an ordered mechanism for the binding/debinding of solutes.
Adipocyte plasma membranes contain two Gi subtypes but are devoid of Go
Authors: Hinsch K.-D. , Rosenthal W. , Spicher K. , Binder T. , Gausepohl H. , Frank R. , Schultz G. , Joost H.G.
Published: July 2002

Antisera generated against synthetic peptides were used to identify G‐protein α‐subunits in plasma membranes from rat adipocytes. Applying the immunoblot technique, we detected two Gs α‐subunits of 42 and 43 kDa, corresponding to the two cholera toxin substrates, and two Gi α‐subunits of 40 and 41 kDa, corresponding to the two pertussis toxin substrates present in these membranes. The 40 kDa protein was tentatively identified as the Gi2, α‐subunit. A serum specific for the Go α‐subunit failed to detect any immunoreactive protein. Thus plasma membranes of adipocytes possess two forms of Gi but not Go.
Cytosolic ADP enhances the sensitivity to tolbutamide of ATP‐dependent K+ channels from pancreatic B‐cells
Authors: Zünkler B.J. , Lins S. , Ohno-Shosaku T. , Trube G. , Panten U.
Published: July 2002

The effects of intracellular purine nucleotides on tolbutamide‐induced block of ATP‐dependent K+ channels from mouse pancreatic B‐cells were studied using the patch‐clamp technique. When applied to the inside of excised patches tolbutamide alone blocked channel activity half‐maximally at 55μM and the concentration‐response curve for the inhibition of K+ channels by tolbutamide was flat. ADP (1 mM), but not other nucleotides (AMP, GTP or GDP) increased the steepness of the concentration‐response curve and decreased the half‐maximally effective tolbutamide concentration to 4.2 μM. It is suggested that the ATP‐dependent K+ channel or a closely related structure contains a receptor which is accessible for cytosolic ADP and controls the sensitivity to tolbutamide.
SecA protein is directly involved in protein secretion in Escherichia coli
Authors: Kawasaki Hisashi , Matsuyama Shin-ichi , Sasaki Shoichi , Akita Mitsuru , Mizushima Shoji
Published: July 2002

A high‐expression plasmid for the secA gene was constructed. The SecA protein was then overproduced in E. coli and purified. The purified SecA stimulated the in vitro translocation of a model secretory protein into inverted membrane vesicles pretreated with 4 M urea. Membrane vesicles from a secAts mutant exhibited lower translocation activity, which was enhanced by SecA. These results indicate that SecA is directly involved in protein secretion across the cytoplasmic membrane.
Structure and developmental expression of the Dα2 gene encoding a novel nicotinic acetylcholine receptor protein of Drosophila melanogaster
Authors: Jonas Petra , Baumann Arnd , Merz Barbara , Gundelfinger Eckart D
Published: July 2002

Nicotinic acetylcholine receptors (nAChRs) represent a heterogeneous group of excitatory neurotransmitter receptors in the insect brain. We have characterized the Dα2 gene of Drosophila
melanogaster, a new member of the nAChR gene family. The protein coding region is interrupted by six introns. The positions of three of these introns are shared with all other nAChR genes. The deduced Dα2 protein shows the structural features of ligand‐binding nAChR α‐subunits. Cytogenetically, the Dα2 gene maps at position 96A of the 3rd chromosome, close to the ALS gene which also encodes an α‐like nAChR subunit. Dα2 transcripts are predominantly expressed in late embryos and in fly heads.
α‐Haemolysin from E. coli purification and self‐aggregation properties
Authors: Ostolaza Helena , Bartolomé Borja , Serra Juan L. , de la Cruz Fernando , Goñi Félix M.
Published: July 2002

An improved, straightforward purification procedure for E. coli α‐haemolysin has been developed. The protein exists in the form of large aggregates, held together mainly by hydrophobic forces. In the presence of urea or other chaotropic agents, the size of the aggregates decreases, while the specific activity is increased.
Single‐chain ribosome inactivating proteins from plants depurinate Escherichia coli 23S ribosomal RNA
Authors: Hartley Martin R. , Legname Giuseppe , Osborn Rupert , Chen Zhaochun , Lord J.Michael
Published: July 2002

The rRNA N‐glycosidase activities of the catalytically active A chains of the heterodimeric ribosome inactivating proteins (RIPs) ricin and abrin, the single‐chain RIPs dianthin 30, dianthin 32, and the leaf and seed forms of pokeweed antiviral protein (PAP) were assayed on E. coli ribosomes. All of the single‐chain RIPs were active on E. coli ribosomes as judged by the release of a 243 nucleotide fragment from the 3′ end of 23S rRNA following aniline treatment of the RNA. In contrast, E. coli ribosomes were refractory to the A chains of ricin and abrin. The position of the modification of 23S rRNA by dianthin 32 was determined by primer extension and found to be A2660, which lies in a sequence that is highly conserved in all species.
8–37h‐CGRP antagonizes actions of amylin on carbohydrate metabolism in vitro and in vivo
Authors: Wang Ming-Wei , Young Andrew A. , Rink Timothy J. , Cooper Garth J.S.
Published: July 2002

8–37hCGRP is a potent antagonist at calcitonin gene‐related peptide (CGRP) liver membrane receptors; it also blocks vasodilator actions of CGRP and the related peptide, amylin, in intact rats. We now report that 8–37hCGRP antagonizes amylin inhibition of insulin‐stimulated labelled glucose uptake into isolated rat soleus muscle, and inhibits amylin‐evoked elevation of plasma lactate and glucose in fasted anaesthetized rats. The different relative potencies of the 3 ligands (amylin, CGRP, 8–37hCGRP) on the liver receptor and on the soleus muscle point to distinct CGRP receptors in liver membranes and amylin receptors on muscle cells.
Sulfide quinone reductase (SQR) activity in Chlorobium
Authors: Shahak Y. , Arieli B. , Padan E. , Hauska G.
Published: July 2002

Membranes of the green sulfur bacterium, Chlorobium limicola f, thiosulfatophilum, catalyze the reduction of externally added isoprenoid quinones by sulfide. This activity is highly sensitive to stigmatellin and aurachins. It is also inhibited by 2‐n‐nonyl‐4‐hydroxyquinoline‐N‐oxide, antimycin, myxothiazol and cyanide. It is concluded that in sulfide oxidizing bacteria like Chlorobium, sulfide oxidation involves a sulfide‐quinone reductase (SQR) similar to the one found in Oscilatoria limnetica [Arieli, B., Padan, E. and Shahak, Y. (1991) J. Biol. Chem. 266. 104–111].
Effects of a single intrastrand d(GpG) platinum adduct on the strand separating activity of the Escherichia coli proteins RecB and RecA
Authors: Villani Giuseppe , Cazaux Christophe , Pillaire Marie-Jeanne , Boehmer Paul
Published: July 2002

RecB and RecA proteins play key roles in the process ofDNA recombination in Escherichia coli and both possess DNA unwinding activities which can displace short regions of duplex DNA in an ATP‐dependent manner in vitro. We have examined the effect of the most abundant DNA adduct caused by the chemotherapeutic agent cM‐diamminedichloroplatinum(II) on those activities. For this purpose, we have constructed a partially duplex synthetic oligonucleotide containing the intrastrand d(GpG) crosslink positioned at a specific site. We report here that both the DNA strand separating and DNA‐dependent ATPase activities of the RecB protein are inhibited by the d(GpG) cis‐ddp adduct. In contrast, neither the unwinding nor the ATPase activities of RecA protein appear to be perturbed by this lesion.
Presence of eight distinct homeobox‐containing genes in cnidarians
Authors: Naito Morihiro , Ishiguro Hiroshi , Fujisawa Toshitaka , Kurosawa Yoshikazu
Published: July 2002

Using the polymerase chain reaction, we identified four different homeobox‐containing genes in Hydra magnipapillata. Three of them, cnox1‐Hm, cnox2‐Hm and cnox4‐Hm, were equivalent to homeobox genes that had already been identified in other species of cnidarians. cnox5‐Hm was a new homeobox gene and was very similar to Mox1 in the mouse. Together with the published data, our results indicate that there are at least eight distinct classes of homeobox genes in cnidarians. These homeobox genes show a maximum of 60 to 77% identity in terms of the amino acid residues in their homeodomains to certain classes of homeobox genes that have been identified in Drosophila.
Mutational analysis of the specific priming signal essential for DNA replication of the broad host‐range plasmid RSF1010
Authors: Honda Yoichi , Akioka Tae , Takebe So , Tanaka Katsunori , Miao Dengming , Higashi Akihisa , Nakamura Toshiaki , Taguchi Yoshitomo , Sakai Hiroshi , Komano Tohru , Bagdasarian Michael
Published: July 2002

To analyze the RSF1010‐specific priming mechanism, a library of randomly mutagenized ssiA sequences was constructed by chemical synthesis using mixed nucleotide phosphoramidites. Synthetic ssiA sequences with the single base‐substitutions were assayed for the SSI activity in E. coli JM109 expressing RepB' primase. It was demonstrated that the activity of ssiA was damaged markedly by single base‐substitutions within the possible stem‐loop structure and its 3'‐flanking region. It is conceivable that these domains are critical in recognition and primer synthesis by RepB' primase.
The antirepressor of phage P1 Isolation and interaction with the C1 repressor of P1 and P7
Authors: Riedel Hans-Dieter , Heinrich Jochen , Heisig Anke , Choli Theodora , Schuster Heinz
Published: July 2002

Two antirepressor proteins, Ant1 and Ant2, of molecular weight 42 and 32 kDa, respectively, are encoded by P1 as a single open reading frame, with the smaller protein initiating at an in‐frame start codon. Another open reading frame, icd, 5′ upstream of and overlapping ant1 is required for ant1 expression. Using appropriate ant gene‐carrying plasmids we have overproduced and purified Ant½ in the form of a protein complex and Ant2 as a single protein. Sequence analysis confirmed the N‐terminal amino acids predicted from the DNA sequence of ant1/ant2, except that the N‐terminal methionine is missing in the Ant2 protein. Under appropriate conditions the C1 repressors of phages P1 and P7 specifically co‐precipitate with the Ant½ complex but not with Ant2 protein alone. The results suggest that the antirepressor may exert its C1‐inactivating function by a direct protein—protein interaction.
Synthetic peptides in the determination of hepatitis A virus T‐cell epitopes
Authors: Ivanov Vadim S. , Kulik Liudmila N. , Gabrielian Andrei E. , Tchikin Leonid D. , Kozhich Alexander T. , Ivanov Vadim T.
Published: July 2002

Computer search for probable T‐epitopes of hepatitis A virus capsid proteins was performed using an integrated set of programs. Eight segments of the VP1, VP2, VP3 and VP4 proteins were chosen and synthesised. Five peptides previously examined as probable B‐epitopes were used as well. All the peptides were tested for their ability to stimulate proliferation of lymph node T‐cells primed with synthetic peptides. Almost all predicted T‐epitopes affected the T‐cell proliferation. None of the peptides had mitogenic activity. We demonstrated that regions 17–33 and 276–298 of VP1 are possible immunodominant promiscuous sites activating lymphocytes of all mouse haplotypes.
Entry of animal viruses and macromolecules into cells
Authors: Carrasco Luis
Published: July 2002

The entry of animal viruses into cells is mediated by conformational changes in certain virion‐particle components. These changes are triggered by the binding of virions to receptors and are influenced by low pH during receptor‐mediated endocytosis. These conformational alterations promote the interaction of some viral proteins with cellular membranes thereby leading to transient pore formation and the disruption of ionic and pH gradients. The entry of toxins that do not possess receptors on the cell surface is promoted during the translocation of the virus genome or the nucleocapsid to the cytoplasm. A model is now presented which indicates that efficient virus translocation through cellular membranes requires energy, that may be generated by a protonmotive force. The entry of some animal viruses, as promoted by low pH, should thus only take place when a pH gradient and/or a membrane potential exist, but will not take place if these are dissipated, even if virion particles are present in an acidic enviroment.
TGFβ1 suppresses EGF‐induced increase in nuclear type 1 protein phosphatase activity at the G1/S transition of hepatocyte proliferation
Authors: Kakinoki Yasutaka , Mizuno Yusuke , Takizawa Norio , Imai Yoko , Miyazaki Tamotsu , Kikuchi Kunimi
Published: July 2002

Nuclear type 1 protein phosphatase (PP1) activity in primary culture of EGF‐stimulated hepatocytes was significantly and transiently increased at the G1/S transition, being about 2.5‐fold, while that in non‐stimulated hepatocytes showed almost no change. On the other hand, non‐nuclear PP1 activity was gradually increased until the G1/S transition, but the activity showed no difference between EGF‐stimulated and non‐stimulated hepatocytes. Under growth‐inhibited conditions in the presence of TGFβ1, the increase in nuclear PP1 activity was completely suppressed, whereas non‐nuclear PP1 activity was little affected. Such close correlation between nuclear PP1 activity and growth factor‐induced positive or negative growth signaling strongly suggests an involvement of PP1 in progression from G1 to S phase of hepatocytes. On Western immunoblotting using antisera for PP1α, PP1γ1, and PP1δ, no isoform showed any change in amount under these conditions. Mechanism(s) of growth‐associated alterations in nuclear PP1 activity is discussed.
Expression of α2‐macroglobulin receptor/low density lipoprotein receptor‐related protein is increased in reactive and neoplastic glial cells
Authors: Lopes M.Beatriz S. , Bogaev Christopher A. , Gonias Steven L. , VandenBerg Scott R.
Published: July 2002

α2‐Macroglobulin receptor/low density lipoprotein receptor‐related protein (α2M‐R/LRP) is a multi‐functional cell‐surface receptor that has been implicated in diverse physiologic processes. In normal human brain, α2M‐R/LRP is expressed principally by pyramidal neurons with localization to cell bodies and proximal processes. By contrast, α2M‐R/LRP is not present in either the cell bodies or processes of most normal macroglia (including astrocytes). In this investigation, we studied the expression of α2M‐R/LRP in the brain, following tissue injury or neoplastic transformation, by immunohistochemistry. Significantly increased α2M‐R/LRP immunoreactivity was identified in reactive astrocytes, indicating that expression of this receptor is regulated in vivo in response to brain injury. α2M‐R/LRP immunoreactivity was also detected in glial cell tumors; this finding is novel since malignant transformation is typically thought to turn off expression of this receptor.
Differential effects of an acyl‐coenzyme A: cholesterol acyltransferase inhibitor on HDL‐induced cholesterol efflux from rat macrophage foam cells
Authors: Hakamata Hideki , Miyazaki Akira , Sakai Masakazu , Sakamoto Yu-Ichiro , Matsuda Hirofumi , Kihara Kohji , Horiuchi Seikoh
Published: July 2002

When rat macrophages were converted to foam cells with acetylated low density lipoprotein (acetyl‐LDL) and then reacted with high density lipoprotein (HDL) and an inhibitor of acyl‐coenzyme A:cholesterol acyltransferase (58‐035) (sequential incubation system), 58‐035 did not enhance HDL‐induced cholesterol efflux. In contrast, when macrophages were exposed to acetyl‐LDL in the presence of both HDL and 58‐035 (simultaneous incubation system), HDL‐induced cholesterol efflux was enhanced 1.6‐fold by 58‐035. Cholesterol efflux with HDL alone was 2‐fold greater in simultaneous incubation than in sequential incubation. These results suggest the presence of an efficient cholesterol efflux pathway in simultaneous incubation which is not available in sequential incubation. This pathway, which we refer to as the neutral cholesterol ester hydrolase‐independent pathway, is characterized by the efflux of lysosome‐derived cholesterol without re‐esterification.
A link between ferritin gene expression and ribonucleotide reductase R2 protein, as demonstrated by retroviral vector mediated stable expression
Authors: Fan Huizhou , Villegas Cristy , Wright Jim A.
Published: July 2002

We have constructed a retroviral expression vector for the mammalian ribonucleotide reductase R2 component. Stable infectants, which express a myc epitope tagged R2 protein from the vector cDNA were obtained and described for the first time. Cells containing the recombinant protein exhibited increased ribonucleotide reductase activity, and were resistant to the antitumour agent hydroxyurea, which targets the R2 component of ribonucleotide reductase. Furthermore, a direct link between ferritin gene expression and R2 protein was observed, since cells containing vector expressed recombinant R2 protein exhibited increased H‐chain and L‐chain ferritin gene expression.
Generation of VV‐hemorphin‐7 from globin by peritoneal macrophages
Authors: Dagouassat Nathalie , Garreau Isabelle , Sannier Frederic , Zhao Qiuyu , Pio Jean Marie
Published: July 2002

Bovine globin has been incubated with mice peritoneal macrophages in order to study its hydrolysis by lysosomal enzymes, among which chiefly cathepsin D. Analysis of resulting peptides, by reversed‐phase high‐performance liquid chromatography (RP‐HPLC), shown the release of a bioactive peptide, VV‐hemorphin‐7. When a carboxyl proteinase inhibitor such as pepstatin A was added, no hemorphin was generated. Our results clearly demonstrated that VV‐hemorphin‐7 generation was principally due to cathepsin D. This study allowed us to hypothetize a possible pathway for in vivo hemorphins appearance from globin catabolism by macrophages.
The inhibitory effect of nitrite, a stable product of nitric oxide (NO) formation, on arginase
Authors: Hrabák A. , Bajor T. , Temesi Ágnes , Mészáros G.
Published: July 2002

Macrophages contain arginase and an inducible NO synthase, demonstrated by using l‐arginine, the common substrate, for production of both nitric oxide and urea. Arginase was inhibited by nitrite, the stable end product of NO. This inhibition was non‐competitive, and could not be explained by the reaction of nitrite with arginine, or by the irreversible covalent modification of arginase, or by the removal of Mn2+, a cofactor of arginase.
Involvement of histone hyperacetylation in triggering DNA fragmentation of rat thymocytes undergoing apoptosis
Authors: Lee Eibai , Furukubo Taku , Miyabe Takashi , Yamauchi Aiko , Kariya Kimio
Published: July 2002

The treatment of rat thymocytes with trichostatin A and sodium butyrate, which are inhibitors of histone deacetylase, resulted in an increase in DNA fragmentation in a concentration‐dependent manner. A significant increase in DNA fragmentation induced by these compounds was observed after a lag time of 2 h. Analysis of the fragmented DNA revealed the production of approximately 50 kb DNA fragments and DNA ladders, the biochemical hallmarks of apoptotic cell death. Judging from a laser scanning microscopic analysis, the inhibitors of histone deacetylase induced nuclear condensation, the morphological feature of apoptosis. Biochemical and morphological analyses demonstrated that trichostatin A and sodium butyrate induced thymocyte apoptosis. Furthermore, hyperacetylation of nuclear histones was observed in thymocytes treated with the inhibitors of histone deacetylase. These effects of sodium butyrate and trichostatin A were seen 0.5 and 1 h, respectively, after incubation of the cells. These results thus indicate that hyperacetylation of nucleosomal histones precedes DNA fragmentation in thymocytes undergoing apoptosis induced by trichostatin A and sodium butyrate.
Isolation of Acein‐2, a novel angiotensin‐I‐converting enzyme inhibitory peptide derived from a tryptic hydrolysate of human plasma
Authors: Nakagomi Kazuya , Yamada Riho , Ebisu Hidetoshi , Sadakane Yutaka , Akizawa Toshifumi , Tanimura Takenori
Published: July 2002

We previously described a novel angiotensin‐I‐converting enzyme (ACE) inhibitory peptide, designated Acein‐1, that was isolated from a tryptic hydrolysate of human plasma. We now report a second such inhibitory peptide, Acein‐2 obtained from the same hydrolysate. The peptide was purified by gel filtration and cation exchange chromatography followed by reversed‐phase gradient and isocratic high performance liquid chromatography. Acein‐2 was found to be a tripeptide, Leu‐Ile‐Tyr, which is thought to correspond to f(518–520) of human α2‐macroglobulin. The synthetic tripeptide showed a potent dose‐dependent inhibition of ACE, with an IC50 value of 0.82 μmol/l. Lineweaver–Burk plots suggested that Acein‐2 as well as the previously described Acein‐1 are non‐competitive inhibitors.
Specific defects in double‐stranded DNA unwinding and homologous pairing of a mutant RecA protein
Authors: Kurumizaka Hitoshi , Aihara Hideki , Ikawa Shukuko , Shibata Takehiko
Published: July 2002

The DNA molecules bound to RecA filaments are extended 1.5‐fold relative to B‐form DNA. This extended DNA structure may be important in the recognition of homology between single‐stranded DNA (ssDNA) and double‐stranded DNA (dsDNA). In this study, we show that the K286N mutation specifically impaired the dsDNA unwinding and homologous pairing activities of RecA, without an apparent effect on dsDNA binding itself. In contrast, the R243Q mutation caused defective dsDNA unwinding, due to the defective dsDNA binding of the C‐terminal domain of RecA. These results provide new evidence that dsDNA unwinding is essential to homology recognition between ssDNA and dsDNA during homologous pairing.
Pigment–protein architecture in the light‐harvesting antenna complexes of purple bacteria: does the crystal structure reflect the native pigment–protein arrangement?
Authors: Leupold D , Voigt B , Beenken W , Stiel H
Published: July 2002

Structural analysis of crystallized peripheral (LH2) and core antenna complexes (LH1) of purple bacteria has revealed circular aggregates of high rotational symmetry (C8, C9 and C16, respectively). Quantum‐chemical calculations indicate that in particular the waterwheel‐like arrangements of pigments should show characteristic structure‐sensitive spectroscopic behavior in the near infrared absorption region. Laser‐spectroscopic data obtained with non‐crystallized, isolated LH2 of Rhodospirillum molischianum are in line with a highly symmetric (C8) circular aggregate, but deviations have been found for LH2 of Rhodobacter sphaeroides and Rhodopseudomonas acidophila. For both the latter, C‐shaped incomplete circular aggregates (as seen only recently in electron micrographs of crystallized LH1–reaction center complexes) may be a suitable preliminary model.
Inhibition of influenza virus replication in cultured cells by RNA‐cleaving DNA enzyme
Authors: Toyoda Tetsuya , Imamura Yoshihiro , Takaku Hiroshi , Kashiwagi Takahito , Hara Koyu , Iwahashi Jun , Ohtsu Yasushi , Tsumura Naoki , Kato Hirohisa , Hamada Nobuyuki
Published: July 2002

Influenza virus replication has been effectively inhibited by antisense phosphothioate oligonucleotides targeting the AUG initiation codon of PB2 mRNA. We designed RNA‐cleaving DNA enzymes from 10‐23 catalytic motif to target PB2‐AUG initiation codon and measured their RNA‐cleaving activity in vitro. Although the RNA‐cleaving activity was not optimal under physiological conditions, DNA enzymes inhibited viral replication in cultured cells more effectively than antisense phosphothioate oligonucleotides. Our data indicated that DNA enzymes could be useful for the control of viral infection.
Laminin‐induced PC‐12 cell differentiation is inhibited following laser inactivation of cellular prion protein
Authors: Graner Edgard , Mercadante Adriana F. , Zanata Sı́lvio M. , Martins Vilma R. , Jay Daniel G. , Brentani Ricardo R.
Published: July 2002

Prions, the etiological agents for infectious degenerative encephalopathies, act by inducing structural modifications in the cellular prion protein (PrPc). Recently, we demonstrated that PrPc binds laminin (LN) and that this interaction is important for the neuritogenesis of cultured hippocampal neurons. Here we have used the PC‐12 cell model to explore the biological role of LN–PrPc interaction. Antibodies against PrPc inhibit cell adhesion to LN‐coated culture plaques. Furthermore, chromophore‐assisted laser inactivation of cell surface PrPc perturbs LN‐induced differentiation and promotes retraction of mature neurites. These results point out to the importance of PrPc as a cell surface ligand for LN.
Anomalous dystroglycan in carcinoma cell lines
Authors: Losasso Carmen , Di Tommaso Francesca , Sgambato Alessandro , Ardito Raffaele , Cittadini Achille , Giardina Bruno , Petrucci Tamara C. , Brancaccio Andrea
Published: July 2002

Dystroglycan is a receptor responsible for crucial interactions between extracellular matrix and cytoplasmic space. We provide the first evidence that dystroglycan is truncated. In HC11 normal murine and the 184B5 non‐tumorigenic mammary human cell lines, the expected β‐dystroglycan 43 kDa band was found but human breast T47D, BT549, MCF7, colon HT29, HCT116, SW620, prostate DU145 and cervical HeLa cancer cells expressed an anomalous ≈31 kDa β‐dystroglycan band. α‐Dystroglycan was udetectable in most of the cell lines in which β‐dystroglycan was found as a ≈31 kDa species. An anomalous ≈31 kDa β‐dystroglycan band was also observed in N‐methyl‐N‐nitrosurea‐induced primary rat mammary tumours. Reverse transcriptase polymerase chain reaction experiments confirmed the absence of alternative splicing events and/or expression of eventual dystroglycan isoforms. Using protein extraction procedures at low‐ and high‐ionic strength, we demonstrated that both the 43 kDa and ≈31 kDa β‐dystroglycan bands harbour their transmembrane segment.
Ubiquitin and the SCFGrr1 ubiquitin ligase complex are involved in the signalling pathway activated by external amino acids in Saccharomyces cerevisiae
Authors: Bernard Florent , André Bruno
Published: July 2002

In response to external amino acids, the permease‐like sensor Ssy1 of Saccharomyces cerevisiae activates a pathway leading to transcriptional induction of several permease genes including AGP1 and PTR2. We previously reported that AGP1 induction requires Grr1, the F‐box protein part of the SCFGrr1 ubiquitin–ligase complex. We show here that ubiquitin, other components of SCFGrr1 and the ubiquitin‐conjugating enzyme Cdc34 are essential for AGP1 and PTR2 induction. This suggests that transduction to these genes of the amino acid signal generated by Ssy1 involves an SCFGrr1‐catalysed ubiquitination step.
Nuclear export of mRNA
Authors: Zenklusen Daniel , Stutz Françoise
Published: July 2002

Export of mRNA through nuclear pore complexes (NPC) is preceded by multiple and well coordinated processing steps, resulting in the formation of an export competent ribonucleoprotein complex (mRNP). Numerous factors involved in the translocation of the mRNP through the NPC and its release into the cytoplasm have been isolated mainly through genetic approaches in yeast, and putative functional homologues have been identified in metazoan systems. Understanding the mechanism of mRNA export relies, in part, on the functional characterization of these factors and the establishment of a complete network of molecular interactions. Here we summarize recent progress in the characterization of yeast and mammalian components implicated in the export of an mRNA from the nucleus to the cytoplasm.
Binding and regulation of HIF‐1α by a subunit of the proteasome complex, PSMA7
Authors: Cho Sayeon , Choi Youn-Jeong , Kim Jeong-Min , Jeong Seong-Tae , Kim Jae-Hoon , Kim Seung-Ho , Ryu Seong-Eon
Published: July 2002

The hypoxia‐inducible factor‐1α (HIF‐1α) is an important transcription factor for cellular responses to oxygen tension. It is rapidly degraded under normoxic conditions by the ubiquitin‐dependent proteasome pathway. Here we report a critical role of the 20S proteasome subunit PSMA7 in HIF‐1α regulation. PSMA7 was found to interact specifically with two subdomains of HIF‐1α. PSMA7 inhibited the transactivation function of HIF‐1α under both normoxic and hypoxia‐mimicking conditions. In addition, we show that the PSMA7‐mediated regulation of HIF‐1α activity is associated with the proteasome pathway.
Characterization of dominant lethal mutations in the yeast plasma membrane H+‐ATPase gene
Authors: Portillo Francisco
Published: July 2002

Site‐directed mutants of yeast ATPase were studied after introduction of mutant alleles into a yeast strain where these alleles were constitutively expressed and the expression of the wild‐type chromosomal ATPase gene was turned off. One objection to this constitutive expression system was made apparent recently, as dominant lethal mutations are lost by gene conversion with the wild‐type allele during the process. Here, the phenotypes of the mutant alleles, which were studied in a constitutive expression system, are re‐evaluated under conditions in which these site‐directed mutants are conditionally expressed. We show that 12 of 25 site‐directed mutations previously described are actually dominant lethal alleles. In addition, we show that dominant mutant proteins interfere with transport of wild‐type ATPase to the plasma membrane.
Patterned artificial juxtacrine stimulation of cells by covalently immobilized insulin
Authors: Ito Yoshihiro , Kondo Satoshi , Chen Guoping , Imanishi Yukio
Published: July 2002

© 1997 Federation of European Biochemical Societies.
Gcn5p is involved in the acetylation of histone H3 in nucleosomes
Authors: Ruiz-Garcı́a Ana B , Sendra Ramon , Pamblanco Mercè , Tordera Vicente
Published: July 2002

© 1997 Federation of European Biochemical Societies.