bluuebunny/crossref_metadata_2025 huggingface dataset:
The Distance Learning as the Reason of Child Abuse under Pandemic of COVID-19
Authors: Afanasiev Dmytro , Oros Oleksandra
Published: June 2021

Researches suggest that child abuse is related to a previous history of violence within the family setting and the evolution of the learning process. The current study was aimed to investigate the exposure of child abuse in the case of distance learning and its relationship to some variables of the social-cognitive processing among parents who potentially assaulted their children. The survey research method was applied. The questionnaire consisted of three blocks of questions: socio-demographic block, parents' impressions of distance learning at school, violence, and parents' aggression towards children. The sample included 308 primary school children’s parents from the Zakarpatska region (Ukraine). Results show that parents' reaction to learning difficulties is not always constructive because most stressful situations provoke verbal aggression and physical violence towards the child. Distance learning and related difficulties have become a major factor in violent and aggressive behavior towards children during quarantine. Most parents who allowed maltreatment toward their children before pandemic COVID-19 also demonstrated it during distance learning. Our study found a link between parents' use of physical violence and verbal aggression with the following variables: duration of lockdown, the function of the teacher in distance learning, parents' assessment of the process and learning outcome, qualitative changes in the relationship between parents and children during quarantine. The study of violent situations against children during distance learning will provide an opportunity to develop effective preventive and corrective measures. The process of informing about situations of violence against children can have a psychoprophylactic effect
O índice de mortalidade das startups brasileiras e a necessidade de políticas públicas para o ecossistema empreendedor
Authors: Lima Iago Ervelee da Silva , Dib Alfredo , Albuquerque Helen Morais de
Published: June 2021

O setor empresarial, em seus diversos nichos de atuação, constitui o mais importante pilar para sustentação econômica e social de qualquer nação, e apresenta, como grande desafio, a necessidade de planejamento para o sucesso no processo de inserção no mercado, esta ausência tem, como um dos principais reflexos, a alta taxa de mortalidade de empreendimentos nos primeiros meses. Isso tanto pode ocorrer em razão da inviabilidade do empreendimento quanto em decorrência da ausência de um planejamento que considere todas as variáveis e condicionantes para o sucesso e sustentabilidade dos empreendimentos. Neste sentido, é necessária a modernização da legislação empresarial brasileira, priorizando novas perspectivas para o planejamento, a exemplo das incubadoras, que se constituem como espaços importantes na colaboração com o processo de planejamento estratégico de empresas que querem se inserir no mercado com riscos mínimos de insucesso.
Cultura cidadã no Brasil: aproximações entre educação fiscal e gestão social
Authors: Almeida Rodrigo José Lima , Lima Isnaya Almeida Brandão
Published: June 2021

Gestão Social e Educação Fiscal são temas recentes que problematizam a questão da cidadania como instrumento regulador da relação Estado e sociedade, a partir de um processo de formação cultural, voltado à conscientização dos cidadãos. Assim sendo, o objetivo deste artigo é discutir a aproximação dos temas educação fiscal e gestão social, baseado na perspectiva de construção da cultura cidadã no Brasil. Para isso, realizou-se uma análise crítica em aportes teóricos de trabalhos publicados a respeito dos temas, na forma de uma revisão narrativa, com o intuito de melhor apresentar as discussões sobre as matérias.  Inicialmente, apresenta-se um resgate histórico do processo de formação do Estado brasileiro, com maior enfoque para as questões político-sociais. Em seguida, aborda-se a influência internacional na construção da cultura cidadã do país, os principais conceitos de cultura política, social e cidadã, além das transformações sociais e populacionais ocorridas no Brasil, desde a colonização portuguesa. Após, expõe-se as principais aproximações e características comuns que tornam a educação fiscal e a gestão social, políticas com forte poder de transformação da sociedade, enfatizando que o somatório da educação fiscal com a gestão social alimenta a esperança por dias melhores, já que possuem a participação popular (cidadão) como a principal estratégia de mudança social no país.
Indicadores da NBC T 15: uma análise da adesão no balanço social da EPAMIG
Authors: Moura Tiago de , Mamedes Amanda David , Brun Sergio Adelar
Published: June 2021

A preocupação da população com os aspectos sociais e ambientais nos últimos anos faz com que as empresas se adequem a apresentar informações contábeis exigidas pela legislação, além de demonstrarem informações sobre ações sociais e ambientais. Este estudo tem como objetivo principal analisar o nível de adesão dos indicadores da Norma Brasileira de Contabilidade NBC T 15 - Informações de Natureza Social e Ambiental, no balanço social da Empresa de Pesquisa Agropecuária de Minas Gerais (EPAMIG). Para atingir o objetivo foram analisados os balanços sociais da EPAMIG dos anos 2016 e 2017. Os demonstrativos foram extraídos do site da empresa, e solicitados via Lei de Acesso à Informação, sendo comparados com os indicadores da NBC T 15. O estudo se justifica pela importância da responsabilidade social e ambiental e da contabilidade como ferramenta na apresentação das informações aos interessados. Trata-se de uma pesquisa de caráter descritiva com abordagem qualitativa, com dados obtidos a partir de análise bibliográfica e documental. Constatou-se que a EPAMIG apresenta informações acerca dos recursos humanos, sendo a maior adesão aos indicadores. Por sua vez, as informações sobre a interação com o ambiente externo e com o meio ambiente não apresentaram nenhum indicador proposto na norma.
Governança corporativa e ética: reflexos em empresa investigada pós Lava Jato
Authors: Borrego Andrea Lopes , Rossini Clauber de Oliveira
Published: June 2021

O presente estudo propõe uma análise da condução empresarial contemporânea envolvida em caso de corrupção de repercussão mundial. Nesse sentido, é avaliado como estudo de caso de um grupo empresarial investigado, no âmbito da Operação Lava Jato, o comportamento ético no enfrentamento das questões ao longo do tempo, seu papel na trajetória da resistência, conflitos de estratégias, contradições e a mudança do discurso visando reverter os abalos na imagem e reputação, rigor e as medidas adotadas pela governança corporativa, a reestruturação e o fortalecimento do compliance, na busca em atender os compromissos assumidos com as autoridades e implementados pelos órgãos de justiça brasileiros e internacionais, bem como o enfrentamento dos impactos socioeconômicos ocorridos até os dias atuais. Avalia-se as transformações em diversos aspectos na condução administrativa do grupo empresarial, na busca por um novo posicionamento no mercado, após abalo em sua reputação. A metodologia de pesquisa utilizada foi de natureza qualitativa, de caráter investigativo. O corpus selecionado para este estudo é a revisão bibliográfica acerca do tema, exame de documentos e registros de comunicados a imprensa, disponibilizados pela própria organização em seu site e/ou através de releases públicos sobre a empresa, e nos processos públicos de investigação judicial, em depoimentos oficiais, desde período anterior ao fato crítico até após exposição do escândalo. Como arcabouços deste estudo foram traçados aspectos ocorridos com as Teorias da Agência e do Custo de Transação.
Forensic handwriting examination and human factors:
Authors:   The Expert Working Group for Human Factors in Handwriting Examination
Published: June 2021

For some 6,000 years, humans have made an indelible mark on history through the loops, strokes, and other characters that constitute the written form of language - handwriting. The study of handwriting is also an important part of forensic science. By analyzing the characteristics of a handwritten note or signature, a trained forensic document examiner may be able to extract valuable information for determining whether a note or signature is genuine, as well as the likely writer. As with all human endeavors, handwriting examination is not immune to errors. In June 2015, the US National Institute of Standards and Technology convened the Expert Working Group for Human Factors in Handwriting Examination to conduct a scientific assessment of the effects of human factors on forensic handwriting examination with the goal of recommending strategies and approaches to improve its practice and reduce the likelihood of errors. This report provides a comprehensive discussion of how human factors relate to all aspects of handwriting examinations including communicating conclusions to all relevant parties through reports and testimony. The report also discusses education, training, and certification as well as the role of quality assurance, quality control, and management in reducing errors.
The image of goddess on the throne in the Bosporan coroplast of the archaic and classical periods (VI – IV centuries BC): iconography and sacred meaning
Authors: Bykovskaya Aleksandra Viktorovna
Published: June 2021

This article explores the peculiarities of application of compositional pattern of the enthroned goddess in the coroplast of the European part of Bosporus. A number of figurines of the East Crimean Historical and Cultural Museum-Reserve of such iconography is published for the first time, including the discarded coroplast products dating back to the IV century BC. The article reviews the emergence of iconography, its origins in the Neolithic cultures of Anatolia, and proliferation. The following sections are dedicated to the analysis of Bosporan terracotta of the enthroned goddess of the archaic and classical periods. The research methodology employs iconographic and semantic analysis, which implies the interpretation of religious representations reflected in the image of deity. A peculiarity Bosporan coroplast lies in popularity of the composition of enthroned goddess from the archaic period, which indicates a special role of the high status goddesses with a variety of features, such as Demeter, Aphrodite, Artemis, and Hecate in the beliefs of Bosporans. Terracotta complexes of the classical period demonstrate diversity of this iconographic type, as well as mark the emergence of characteristic attributes that allow identifying the image of deity. Coroplast data testify to the growing popularity of the goddess of Phrygian origin Cybele in the IV century BC. A hypothesis is advanced on the existence of a prototype of the number of figurines – the local cult statue of Cybele.
Understanding the evolution of multiple drug resistance in structured populations
Authors: McLeod David V , Gandon Sylvain
Published: June 2021

The evolution of multidrug resistance (MDR) is a pressing public health concern. Yet many aspects, such as the role played by population structure, remain poorly understood. Here, we argue that studying MDR evolution by focusing upon the dynamical equations for linkage disequilibrium (LD) can greatly simplify the calculations, generate more insight, and provide a unified framework for understanding the role of population structure. We demonstrate how a general epidemiological model of MDR evolution can be recast in terms of the LD equations. These equations reveal how the different forces generating and propagating LD operate in a dynamical setting at both the population and metapopulation levels. We then apply these insights to show how the LD perspective: (i) explains equilibrium patterns of MDR, (ii) provides a simple interpretative framework for transient evolutionary dynamics, and (iii) can be used to assess the consequences of different drug prescription strategies for MDR evolution.
Handling of intracellular K+ determines voltage dependence of plasmalemmal monoamine transporter function
Authors: Bhat Shreyas , Niello Marco , Schicker Klaus , Pifl Christian , Sitte Harald H , Freissmuth Michael , Sandtner Walter
Published: June 2021

The concentrative power of the transporters for dopamine (DAT), norepinephrine (NET), and serotonin (SERT) is thought to be fueled by the transmembrane Na+ gradient, but it is conceivable that they can also tap other energy sources, for example, membrane voltage and/or the transmembrane K+ gradient. We have addressed this by recording uptake of endogenous substrates or the fluorescent substrate APP+(4-(4-dimethylamino)phenyl-1-methylpyridinium) under voltage control in cells expressing DAT, NET, or SERT. We have shown that DAT and NET differ from SERT in intracellular handling of K+. In DAT and NET, substrate uptake was voltage-dependent due to the transient nature of intracellular K+ binding, which precluded K+ antiport. SERT, however, antiports K+ and achieves voltage-independent transport. Thus, there is a trade-off between maintaining constant uptake and harvesting membrane potential for concentrative power, which we conclude to occur due to subtle differences in the kinetics of co-substrate ion binding in closely related transporters.
You can keep your coat on
Authors: Bedwell Gregory J , Engelman Alan N
Published: June 2021

High-resolution imaging techniques reveal new insights into the actions of the retrovirus HIV-1 inside host cells.
Natural infection with Trypanosoma cruzi in bats captured in Campeche and Yucatán, México
Authors: Torres-Castro Marco , Cuevas-Koh Naomi , Hernández-Betancourt Silvia , Noh-Pech Henry , Estrella Erendira , Herrera-Flores Belén , Panti-May Jesús A. , Waleckx Etienne , Sosa-Escalante Javier , Peláez-Sánchez Ronald
Published: June 2021

Introduction: Bats have been reported as hosts of the Trypanosoma cruzi protozoan, the etiologic agent of American trypanosomiasis, an endemic zoonotic disease in México.Objective: To describe T. cruzi infection in bats from the states of Campeche and Yucatán, México.Materials and methods: Captures were made from March to November, 2017, at three sites in Yucatán and one in Campeche. Up to four mist nets on two consecutive nights were used for the capture. The bats’ species were identified and euthanasia was performed to collect kidney and heart samples for total DNA extraction. Trypanosoma cruzi infection was detected by conventional PCR with the amplification of a fragment belonging to the T. cruzi DNA nuclear.Results: Eighty-six bats belonging to five families (Vespertilionidae, Noctilionidae, Mormoopidae, Phyllostomidae, and Molossidae) and 13 species (Rhogeessa aeneus, Noctilio leporinus, Pteronotus davyi, P. parnellii, Artibeus jamaicensis, A. lituratus, A. phaeotis, Glossophaga soricina, Carollia sowelli, Chiroderma villosum, Uroderma bilobatum, Sturnira parvidens, and Molossus rufus) were captured. Infection frequency by PCR was 30,2% (26/86) detected only in the renal tissue. The infected species were P. parnellii, G. soricina, A. lituratus, A. jamaicensis, S. parvidens, C. villosum, and R. aeneus.Conclusions: Our results confirmed the participation of several bat species as hosts in the T. cruzi transmission cycle in the region. Further studies are necessary to establish the importance of these animals in the zoonotic transmission of T. cruzi.
Chronic Cystoisospora belli infection in a Colombian patient living with HIV and poor adherence to highly active antiretroviral therapy
Authors: Galván-Díaz Ana Luz , Alzate Juan Carlos , Villegas Esteban , Giraldo Sofía , Botero Jorge , García-Montoya Gisela
Published: June 2021

Cystoisospora belli is an intestinal Apicomplexan parasite associated with diarrheal illness and disseminated infections in humans, mainly immunocompromised individuals such as those living with the human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS). An irregular administration of highly active antiretroviral therapy (HAART) in HIV patients may increase the risk of opportunistic infections like cystoisosporiasis.We describe here a case of C. belli infection in a Colombian HIV patient with chronic gastrointestinal syndrome and poor adherence to HAART. His clinical and parasitological cure was achieved with trimethoprim-sulfamethoxazole treatment. Although a reduction in the number of C. belli cases has been observed since the use of HAART, this parasite still has to be considered as a differential diagnosis of diarrheal disease in HIV/AIDS patients.Effective interventions enhancing adherence to HAART should be included in HIV patient care programs.
Neuromedin U and neurotensin may promote the development of the tumour microenvironment in neuroblastoma
Authors: Yang Daheng , Zhang Xianwei , Li Zheqian , Xu Fei , Tang Chenjie , Chen Hongbing
Published: June 2021

Stage 4S neuroblastoma, as defined by the International Neuroblastoma Staging System committee (INSS), is known to regress spontaneously and have a more favourable outcome compared with stage 4 tumours. Comparing the molecular differences between these two stages may provide insights into the progression of neuroblastoma. Our study aimed to explore the molecular differences in the tumour microenvironment (TME) between INSS stage 4S and stage 4 tumours to provide an insight into the mechanisms underlying the biological processes of neuroblastoma. We downloaded the datasets GSE120572 and GSE73517 from the GEO database and pre-processed them using the limma package. CIBERSORT deconvolution agorithm was applied to analyse the differences in 22 infiltrating immune leukocyte subsets between the two stages. We used gene ontology (GO) enrichment analysis to determine the biological process (BP) annotation of differentially expressed genes (DEGs) using the online WebGestalt tool. Hub genes were determined in the STRING database and Cytoscape, and the expression of these genes was verified in the Oncomine database. Then these critical genes were performed survival analysis in TARGET database. We further validated the hub genes using a transwell assay and wound healing assay to detect the function of the genes in the neuroblastoma cell line SK-N-BE(2). GO analysis revealed that the 216 DEGs between stage 4S and stage 4 were enriched in aggressive biological processes. Neuromedin U (NMU) and neurotensin (NTS), which were significantly associated with patients’ overall survival rate, were verified to be elevated in stage 4, and to promote the proliferation and invasion of the SK-N-BE(2) cell. Tumour infiltrating leukocyte analysis showed a high infiltration of regulatory T cells and type 2 tumour-associated macrophages in stage 4 but not in stage 4S. Results of gene co-expression correlation, and the results of previous studies, suggest that NMU and NTS may play certain roles in modulating TME, thus facilitating the progression of neuroblastoma.
Influence of Anxiety, Depression and Self-Esteem on Quality of Life in Patients with Rheumatoid Arthritis
Authors: Bae Sanghyun , Hong Insook , Cho Ok-Hee
Published: June 2021

Purpose: The purpose of this study was to investigate the influence and relationship among anxiety, depression, self-esteem, and quality of life, along with factors affecting quality of life, on patients with rheumatoid arthritis.Methods: This study was a cross-sectional descriptive study, and 200 individuals with rheumatoid arthritis who visited a single university hospital as outpatients were recruited through convenience sampling. Using a structured questionnaire, a survey was conducted regarding the general characteristics, anxiety, depression, self-esteem, and quality of life. Collected data were analyzed using t-test, ANOVA, and regression analysis.Results: Results showed that lower levels of anxiety or depression and higher levels of self-esteem were associated with improved quality of life. Depression was identified as the main factor affecting quality of life, followed by anxiety, glucocorticoid treatment, time elapsed after diagnosis, and occupational status.Conclusion: These findings confirmed that depression, anxiety, and glucocorticoid medication are factors influencing quality of life in patients with rheumatoid arthritis, Duration since diagnosis, and occupation should be considered in order to improve the quality of life of these patients with rheumatoid arthritis. The occupation and treatment-related characteristics of the patients must be considered, with particular focus on depression and anxiety.
HeLa cell messenger RNAs of widely differing sizes encode certain heat shock proteins in the Mr region of 72 000–74 000
Authors: Cato Andrew C.B. , Sillar Gillian M. , Kioussis Joanna , Burdon Roy H.
Published: July 2002

Cloned cDNA sequences coding for specific 72 000–74 000 M
r HeLa cell heat shock proteins (HSPs) have been used as probes to examine cytoplasmic and nuclear RNA of heat shocked HeLa cells. The mRNAs for these HSPs vary widely in size. Whilst the β‐, δ‐ and ε‐HSPs are encoded in mRNAs of 1.9 kb, the γ‐HSP arises from an mRNA three times that size. A search for putative nuclear precursors to these mRNAs revealed high M
r candidates at 15.8 kb which accumulate 1–2 h after the initial heat shock, thus supporting the notion that transcriptional control is important in the initial heat shock response.
Amino acid sequence at the major phosphorylation site on bovine kidney branched‐chain 2‐oxoacid dehydrogenase complex
Authors: Cook Kenneth G. , Lawson Rowena , Yeaman Stephen J. , Aitken Alastair
Published: July 2002

Inactivation of branched‐chain 2‐oxoacid dehydrogenase complex correlates with phosphorylation at one site on the α subunit of the E1 component. The amino acid sequence surrounding this phosphorylated serine residue has now been determined. This sequence shows certain similarities with the sequence surrounding phosphorylated residue(s) on pyruvate dehydrogenase complex.
Angiotensin II inhibits hepatic cAMP accumulation induced by glucagon and epinephrine and their metabolic effects
Authors: Morgan Noel G. , Exton John H. , Blackmore Peter F.
Published: July 2002

Incubation of isolated hepatocytes containing normal Ca2+ levels with angiotensin II, vasopressin or A23187 caused significant inhibition of the cAMP response to glucagon. Angiotensin II also inhibited cAMP accumulation induced by either glucagon or epinephrine in Ca2+‐depleted hepatocytes. When sub‐maximal doses of hormone were employed such that cell cAMP was elevated only 3–4‐fold (∼2 pmol cAMP/mg wet wt cells) inhibition by angiotensin II was correlated with a decrease in phosphorylase activation. The data demonstrate that inhibition of hepatic cAMP accumulation results in reduced metabolic responses to glucagon and epinephrine and do not support the contention that the hepatic actions of glucagon are independent of cAMP.
Oxygen‐derived radicals from Trypanosoma cruzi‐stimulated human neutrophils
Authors: Docampo Roberto , Casellas Angela M. , Madeira Eliana D. , Cardoni Rita L. , Moreno Silvia N.J. , Mason Ronald P.
Published: July 2002

This study provides biochemical and electron spin resonance spectroscopic evidence that contract of human polymorphonuclear leukocytes with antibody‐coated Trypanosoma cruzi triggers the respiratory burst. Oxygen consumption, superoxide anion and hydrogen peroxide release were stimulated under conditions of polymorphonuclear leukocyte‐mediated killing. This stimulation did not occur under non‐killing conditions when antibody was omitted. A common mechanism of cytotoxicity of human polymorphonuclear leukocytes against different T. cruzi forms is suggested by the triggering of the respiratory burst by antibody‐coated epimastigotes and trypomastigotes.
An enzyme synthesizing fructose 2,6‐bisphosphate occurs in leaves and is regulated by metabolite effectors
Authors: Cséke Csaba , Buchanan Bob B.
Published: July 2002

An enzyme catalyzing the ATP and fructose 6‐phosphate‐dependent synthesis of fructose 2,6‐bisphosphate, a regulator of glycolysis and gluconeogenesis, has been identified and partially purified from plants, specifically the cytoplasmic fraction of spinach leaf parenchyma cells. The enzyme, designated fructose 6‐phosphate, 2‐kinase, showed no response to a protein phosphorylation system known to inhibit the corresponding enzyme in mammalian cells, but it responded strikingly to metabolite effectors (Pi, an activator/PGA, an inhibitor) through changes in substrate affinity and maximal velocity. The observed pattern of regulation suggests a role for chloroplasts in controlling cytoplasmic carbon processing.
Stable isotope containing peptides as probes of ligand—receptor interactions
Authors: Wu Arthur , Muthukumaraswamy Natesa , Glasel Jay A. , Mackin William M. , Becker Elmer L. , Freer Richard J.
Published: July 2002

The synthesis and biological evaluation of the stable isotope containing chemotactic peptide, deuteroformyl‐methionyl‐leucyl‐phenylalanine (C2DO‐Met‐Leu‐Phe‐OH) is reported. The results, using lysosomal enzyme release from cytochalasin B‐treated rabbit neutrophils for biological evaluation indicates a 3–4 fold enhancement over CHO‐Met‐Leu‐Phe‐OH itself. This is consistent with previous speculation that the formyl proton hydrogen bonds with a critical area of the chemotactic peptide receptor of rabbit neutrophils.
Interstrand DNA crosslinks due to AP (apurinic/apyrimidinic) sites
Authors: Goffin Colette , Verly Walter G.
Published: July 2002

Storage of a solution of DNA containing apurinic sites, even at 4°C leads to the appearance of interstrand crosslinks. Possible biological consequences of these crosslinks, when they appear in cell DNA, are briefly discussed. Formation of interstrand crosslinks in DNA containing tritium‐labelled thymine and kept in an aqueous solution might be due, at least partly, to the loss of bases by the autoirradiated DNA.
Cellular localization of the receptor‐dependent and receptor‐independent uptake of human LDL in the liver of normal and 17α‐ethinyl estradiol‐treated rats
Authors: Harkes Leen , Berkel Theo J.C.van
Published: July 2002

The cellular localization in the liver of the receptor‐dependent and ‐independent uptake of human low density lipoprotein (LDL) in normal and 17α‐ethinyl estradiol‐treated rats was investigated by the simultaneous in vivo injection of human 131I‐LDL and human reductive methylated 125I‐LDL. The cells were subsequently isolated by a low temperature method. In untreated rats, after 30 min of in vivo circulation of human LDL, 57% of the receptor‐dependent liver‐association of human LDL occurs in non‐parenchmal cells and 43% in parenchymal cells. Estradiol treatment of rats for 3 days selectively increases the receptor‐dependent cell‐association of human LDL with hepatocytes (17‐fold), while the receptor‐dependent cell‐association with non‐parenchymal cells is not affected.
The relaxation time for a cruciform structure in superhelical DNA
Authors: Vologodskii A.V. , Frank-Kamenetskii M.D.
Published: July 2002

We have calculated the relaxation time of a cruciform structure in superhelical DNA as a function of the superhelix density for palindromic regions of different lengths. The relaxation time has a sharp maximum at the superhelix density which corresponds to the equilibrium transition point between the cruciform structure and the regular double helix. This maximal value is shown to depend dramatically on the length of the palindromic region.
The cellulolytic enzymes of Trichoderma reesei as a system of homologous proteins
Authors: Bhikhabhai Ramagauri , Göran Pettersson L.
Published: July 2002

The partial amino acid sequences of cyanogen bromide peptides of endoglucanase II, 1,4‐β‐glucan glucanohydrolase (from Trichoderma reesei) were determined by automated Edman degradation with liquid and solid phase techniques. Computer programs for finding distant relationships between the two amino acid sequences were used to compare the partial sequences of endoglucanase II with the complete sequence of cellobiohydrolase I. Homologous regions were found for all the cyanogen bromide peptides.
Fluorescence polarization study of tertiary structure of DNA within bacteriophage γ
Authors: Shurdov M.A. , Gruzdev A.D.
Published: July 2002

The fluorescence polarization of acridine orange‐stained oriented γ phages was measured. The parameters of DNA packing within the phage head and were calculated (φ, angle between the direction of a small segment of DNA and the phage axis). It is shown that simple models of γ phage DNA tertiary structure are not consistent with calculated values. A new model is proposed.
The effect of carbacyclin, a prostaglandin analogue, on adenylate cyclase activity in platelet membranes
Authors: Stein Janet M. , Martin B.R.
Published: July 2002

The effect of carbacyclin, a chemically stable analogue of prostacyclin, on the activity of adenylate cyclase in platelet membrane was measured, and compared with the effect of PGE1. When GTP was added in concentrations up to 10 μM the activation of adenylate cyclase by carbacyclin was increased, whereas higher concentrations of GTP were inhibitory. The addition of a non‐hydrolysable analogue of GDP, guanosine 5′‐[β‐thio]diphosphate (GDP[βS]) resulted in a dose‐dependent inhibition of adenylate cyclase activation by carbacyclin; this inhibition was relieved by adding increased amounts of GTP.
GTPase activity associates with the inhibitory GTP‐binding regulatory component of adenylate cyclase purified from rat brain
Authors: Enomoto Keiichi , Asakawa Takeo
Published: July 2002

The inhibitory regulatory component of adenylate cyclase (Ni) was highly purified from rat brain synaptic membranes. A low K
m GTPase activity was always associated with Ni through the purification, and the recovery of GTPase activity correlated well with that of Ni. Purified Ni was hardly ADP‐ribosylated by islet‐activating protein (IAP). A heat‐labile factor in the fraction of the stimulative regulatory component (Ns) restored ADP‐ribosylation and also activated the GTPase about 2‐fold. NaF which was reported to interact with Ni markedly reduced GTPase activity. The purified Ni fraction inhibited adenylate cyclase only in the presence of a heat‐stable factor found in the partially purified regulatory component. GTPase and inhibitory activities were weak in myelin which contained only a small amount of Ni. These findings support the view that GTPase activity is an intrinsic activity of Ni and some factors are necessary for the function of Ni.
Stimulation by serotonin of 40 kDa and 20 kDa protein phosphorylation in human platelets
Authors: de Chaffoy de Courcelles D. , Roevens P. , van Belle H.
Published: July 2002

In human platelets, serotonin is known to induce a shape change followed by (reversible) aggregation. Recently, it was found that the amine triggers the elevation of cytosolic free calcium and activates phospholipase C. On stimulation of human platelets with serotonin we found an immediate increase in protein kinase C activity, phosphorylating its 40 kDa substrate protein. A 20 kDa protein, most likely the myosin light chain, was phosphorylated to the same extent. Ketanserin, a highly selective serotonin‐S2 antagonist inhibited both phosphorylation processes at subnanomolar concentrations.
Effect of the phorbol ester TPA on PTH secretion Evidence for a role for protein kinase C in the control of PTH release
Authors: Brown Edward M. , Redgrave Jamie , Thatcher Joseph
Published: July 2002

Parathyroid hormone (PTH) secretion is stimulated by low extracellular calcium (Ca2+) in association with a reduction in cyosolic Ca2+, indicating that this cell type does not conform to classical models of stimulus‐secretion coupling. We used the phorbol ester TPA (12‐O‐tetradecanoyl phorbol 13‐acetate), which directly activates protein kinase C, to investigate the possible role of this enzyme in the unusual secretory properties of the parathyroid cell. TPA causes a dose‐dependent stimulation of PTH release inhibited by high extracellular Ca2+ (EC50 = 10 nM) but has relatively little effect on secretion stimulated by low Ca2+. This effect was mimicked by the β4‐isomer of phorbol 12,13‐didecanoate which also activates kinase C, but not by the α4‐isomer, which has no effect on this enzyme. TPA does not modify cellular cAMP or cytosolic Ca2+ in the parathyroid cell indicating that its effects on PTH secretion are not mediated indirectly via changes in these second messengers. These results suggest that inhibition of PTH release at high Ca2+ might be related to a reduction in protein kinase C activity which can be overcome when the enzyme is directly activated by TPA.
Activation of yeast 6‐phosphofructo‐2‐kinase by protein kinase and phosphate
Authors: Yamashoji Shiro , Hess Benno
Published: July 2002

6‐phosphofructo‐2‐kinase (PFK2) is activated by a cAMP‐dependent protein kinase, and inactivated by phosphatase, indicating the interconversion of PFK2. Inorganic phosphate also activates PFK2, and the optimum pH for the PFK2 activity varies with the concentration of phosphate. Phosphate also enhances the inactivation of PFK2 by citrate, suggesting that phosphate acts as a regulator of PFK2.
Assignment of resonances of exchangeable protons in the NMR spectrum of the complex formed by Escherichia coli ribosomal protein L25 and uniformly nitrogen‐15 enriched 5 S RNA fragment
Authors: Kime Matthew J.
Published: July 2002

The downfield proton NMR spectrum of the aqueous nucleoprotein complex formed by Escherichia coli ribosomal protein L25 and uniformly nitrogen‐15 enriched 5 S RNA fragment is presented. Many proton resonances show the effects of scalar coupling to nitrogen‐15 and these resonances arc assigned to nucleic acid imino protons. Selective nitrogen‐15 decoupling difference proton spectroscopy revealed nitrogen‐15 and proton chemical shift correlations from which the base types of nucleic acid imino proton resonances could be assigned because the nitrogen‐15 chemical shifts of nucleic acid guanine and uracil imino nitrogens have separate small ranges for both nucleoproteins and isolated nucleic acids.
Effect of pertussis toxin on α2‐adrenoceptors: decreased formation of the high‐affinity state for agonists
Authors: García-Sáinz J.Adolfo , Luis Boyer José , Michel Thomas , Sawyer Diane , Stiles Gary L. , Dohlman Henrik , Lefkowitz Robert J.
Published: July 2002

Administration of pertussis toxin to hamsters abolishes the α2‐adrenergic inhibition of adenylate cyclase in their adipocytes. The toxin did not modify the number of adipocyte α2‐adrenoceptors or their affinity for antagonists. In contrast, the affinity for agonists was significantly diminished in adipocyte membranes obtained from pertussis toxin‐treated hamsters as compared to the controls. This decrease in affinity was due to a significant diminution in the proportion of sites displaying the high‐affinity state for agonists. It is concluded that pertussis toxin induces a shift in the proportion of sites in high‐ and low‐affinity states for agonists towards the low‐affinity conformation.
The roles of intrinsic kinase and of kinase/activator protein in the enhanced phosphorylation of pyruvate dehydrogenase complex in starvation
Authors: Kerbey Alan L. , Richardson Lynne J. , Randle Philip J.
Published: July 2002

Extracts of heart mitochondria from fed and from 48 h starved rats subjected to gel filtration on Sephacryl S‐300 gave 4 major protein peaks. Pyruvate dehydrogenase complex eluted in the void volume and was assayed for intrinsic pyruvate dehydrogenase kinase activity which was increased approximately 3‐fold by 48 h starvation of the rat. A second fraction, containing peaks 2 and 3 which overlapped, enhanced the activity of the intrinsic kinase and corresponds to kinase/activator protein described previously. Its activity was increased 1.5‐fold by starvation.
Amino acid sequence round the site of phosphorylation in isocitrate dehydrogenase from Escherichia coli ML308
Authors: Borthwick A.C. , Holms W.H. , Nimmo H.G.
Published: July 2002

Isocitrate dehydrogenase from Escherichia coli is regulated by a reversible phosphorylation mechanism. We report here the amino acid sequence round the phosphorylation site; this is the first such sequence to be reported for a bacterial protein kinase. The sequence does not resemble sequences phosphorylated by cyclic AMP‐dependent protein kinase.
Characterization of new enkephalin‐containing peptides in the adrenal medulla by immunoblotting
Authors: Patey Gilles , Liston Dane , Rossier Jean
Published: July 2002

Immunoblotting combined with radioimmunoassays (RIAs) directed specifically towards certain sequences of the proenkephalin molecule has been used to characterize the enkephalin‐containing peptides (ECPs) present in the bovine adrenal medulla. Immunoblotting allowed the simultaneous visualization of all ECPs present in a crude extract of this gland. Combining this technique with RIAs we have been able to characterize a new high molecular mass ECP, a 23.3‐kDa protein which contains the amino‐terminal part of proenkephalin and ends with the sequence of Leu‐enkephalin at its carboxy‐terminus.
Fusion between Sendai virus envelopes and biological membranes as monitored by energy transfer methods
Authors: Chejanovsky N. , Eytan G.D. , Loyter A.
Published: July 2002

Membrane fusion
Sendai virus
Energy transfer
Intermediates in the conversion of prekeratin into keratin molecules in human epidermis
Authors: Katagata Yohtaro , Aso Kazuo
Published: July 2002

In order to elucidate the relationship between prekeratin and keratin, we performed pulse‐chase experiments using [35S]methionine (35S‐Met) in vitro. Of 6 prekeratin molecules (49, 52, 55, 62, 69 and 71 kDa) that incorporated 35S‐Met, the 55‐kDa prekeratin incorporated the most 35S‐Met. In 3 molecules (52, 55 and 62 kDa) incorporation was decreased at 30 min after being chased; however, incorporation of only two molecules (55 and 62 kDa) of the 6 prekeratins was increased at 60 min. From these results and our previous data, we conclude that the initial stage of processing is as follows: 3 prekeratin molecules (52, 55 and 62 kDa) are first cleaved in the N‐terminal region, then two prekeratin molecules (55 and 69 kDa) are processed to intermediates (52 and 62 kDa) by some proteolytic enzyme(s).
Amino acid sequence and S‐S bonds of Penicillium brevicompactum guanyl‐specific ribonuclease
Authors: Shlyapnikov S.V. , Kulikov V.A. , Yakovlev G.I.
Published: July 2002

Ribonuclease
Penicillium brevicompactum
Covalent structure
Primary sequence differences between Chido and Rodgers variants of tryptic C4d of the human complement system
Authors: Hellman Ulf , Eggertsen Gösta , Lundwall Åke , Engström Åke , Sjöquist John
Published: July 2002

Human tryptic C4d of the Chido and Rodgers variant was fragmented by cyanogen bromide and trypsin. The fragments were characterized by amino acid analysis and sequence determination. Polymorphism between the two genetic variants was detected in 5 positions. Four were closely located (residues 141, 142, 145, 146), where Leu, Ser, Ile, His occurred in the Chido variant and Pro, Cys, Leu, Asp in the Rodgers variant, respectively. In position 94 Gly was found in Chido and Asp in Rodgers. Alignment of the fragments was performed and it is concluded that tryptic C4d of both variants contains 346 residues.
Primary structure of the major glycans of the N‐acetyllactosamine type derived from the human immunoglobulins M from two patients with Waldenström's macroglobulinemia
Authors: Cahour A. , Debeire P. , Hartmann L. , Montreuil J. , Van Halbeek H. , Vliegenthart J.F.G.
Published: July 2002

The carbohydrate chains of the pathological human immunoglobulins M from two patients with Waldenström's macroglobulinemia were released by hydrazinolysis. The N‐acetyllactosamine‐type glycans were obtained by affinity chromatography on concanavalin A and fractionated by high‐voltage paper electrophoresis. The primary structure of the major compounds was elucidated on the basis of carbohydrate analysis, methylation analysis, including mass‐spectrometry, and 500 MHz 1H‐NMR spectroscopy. For both patients, this appeared to be a monosialyl monofucosyl biantennary structure; the compounds differed by the presence of an intersecting N‐acetylglucosamine residue.
The synergistic action of caffeine or adenosine on glucose stimulation of liver glycogen synthase phosphatase activity
Authors: Gilboe Daniel P. , Nuttall F.Q.
Published: July 2002

Recent studies indicate that glucose directly stimulates synthase phosphatase activity in vitro but only at high, non‐physiological concentrations. Present results demonstrate that at a physiological concentration glucose can be stimulatory, provided that an appropriate second effector is present. Caffeine and adenosine are examples of such effectors which act synergistically with glucose to enhance synthase phosphatase activity. Caffeine but not adenosine enhances glucose stimulation of phosphorylase phosphatase activity. In the absence of glucose, caffeine but not adenosine stimulates both synthase and phosphorylase phosphatase reactions. Thus, glucose regulation of glycogen synthase activation in vivo could require a second effector. Neither the identity nor source of such an effector is known. The putative regulator could be a mediator for a hormone such as insulin. The present work suggests that the chemical nature of the effector might be that of a derivatized purine of which nucleosides are an example.
Primary structure of a regulating factor, 15 kDa protein, of ATP synthase in yeast mitochondria
Authors: Yoshida Yukuo , Wakabayashi Sadao , Matsubara Hiroshi , Hashimoto Tadao , Tagawa Kunio
Published: July 2002

The amino acid sequence of a factor, 15 kDa protein, which facilitates the formation of, and stabilizes the inactivated complex between mitochondrial ATPase and intrinsic inhibitor was established. The factor was found to be composed of 83 amino acid residues and to have an M
r of 9450, though the apparent M
r was 15 000 when determiend by SDS—polyacrylamide gel electrophoresis. The factor was characterized as a basic protein with 18 basic and 12 acidic amino acid residues. The amino acid sequence of the factor showed significant homology with those of yeast ATPase inhibitor and the 9 kDa protein which acts in concert with the 15 kDa protein in stabilizing the inactivated ATPase complex.
Extensions of the signal hypothesis ‐ sequential insertion model versus amphipathic tunnel hypothesis
Authors: Rapoport Tom A.
Published: July 2002

Signal hypothesis
Protein translocation
Membrane insertion
Amphipathic tunnel hypothesis
Identification of glycine spin systems in 1H NMR spectra of proteins using multiple quantum coherences
Authors: Boyd Jonathan , Dobson Christopher M. , Redfield Christina
Published: July 2002

Double‐quantum filtered COSY and triple‐quantum filtered COSY techniques have been compared for the tripeptide Gly‐Tyr‐Gly and for human lysozyme. The insertion of a triple‐quantum filter in the COSY experiment leads to dramatic spectral simplification in the fingerprint region of the spectrum and permits the specific identification of glycine spin systems in the complex 1H NMR spectra of proteins. The assignment of these peaks to glycine Hα can be confirmed using 2D double‐quantum correlated spectroscopy.
Amino acid sequence of rubredoxin from Desulfovibrio desulfuricans strain 27774
Authors: Hormel Scott , Walsh Kenneth A. , Prickril Ben C. , Titani Koiti , LeGall Jean , Sieker Larry C.
Published: July 2002

The amino acid sequence of a rubredoxin from Desulfovibrio desulfuricans (strain 27774) has been determined. Comparison with rubredoxins from other species reveals pervasive homology, including the regions known to provide the cysteine ligands to the iron atom in several rubredoxins. Neither an extra cysteinyl residue nor a unique histidyl residue in the new sequence is located in the sequence in such a way that, by homology, a functional role in the structure is suggested.
A possible model for the organic prosthetic group of the water‐splitting complex in the cyanobacterium Anacystis nidulans
Authors: Pistorius Elfriede K. , Gau Achim E.
Published: July 2002

O2‐evolving photosystem II complexes, which were isolated from the cyanobacterium Anacystis nidulans as described previously [(1986) Biochim. Biophys. Acta 849, 203‐210], were further purified on a Sepharose 6B column. These complexes retain the L‐amino acid oxidase protein. Moreover, various types of photosystem II inhibitors were tested for their effect on L‐amino acid oxidase activity. The results show that chlorpromazine, 2,4,6,2',4',6'‐hexanitrodiphenylamine, and o‐phenanthroline inhibited photosynthetic O2 evolution as well as L‐amino acid oxidase activity, while 3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea and 4‐hydroxy‐3,5‐diiodobenzonitrile only inhibited photosynthetic O2 evolution. These results further support a functional role of the L‐amino acid oxidase protein in photosynthetic O2 evolution. We suggest that a flavin‐derived molecule ‐ possibly a 10,10a‐ring‐opened derivative of FAD ‐ is the organic prosthetic group of the water‐splitting complex in A. nidulans and that this flavin derivative is able to chelate mangenese.
Kurloff cell proteoglycans
Authors: Landemore Gérard , Letaïef Slim-Eric , Bocquet Jean , Izard Jacques
Published: July 2002

This paper reports the first direct demonstration of de novo synthesis ofchondroitin sulphate proteoglycans by Kurloff cells. This was achieved using highly purified splenic Kurloff cells labelled in vitro with [35S]sulphate and D‐[U‐3H]glucosamine. A single population of sulphated proteoglycans was observed after dissociative extraction, DEAE‐cellulose chromatography, Sepharose CL 6B chromatography and fluorography after electrophoresis. These were large, highly anionic proteoglycans and were completely digested by chondroitinase AC or ABC. Moreover, glycosaminoglycan extracted from Kurloff cells had the electrophoretic mobility of control chondroitin sulphate.
Somatostatin and α2‐adrenergic agonists selectively inhibit vasopressin‐induced cyclic AMP accumulation in MDCK cells
Authors: Friedlander Gerard , Amiel Claude
Published: July 2002

The effect of somatostatin and α2‐adrenergic agonists on cyclic AMP accumulation was examined in MDCK cells, grown in denned medium. These hormones inhibited vasopressin‐induced cyclic AMP formation, without affecting either the basal or the glucagon‐ and prostaglandin E2‐stimulated level. Pretreating the cells with pertussis toxin, or incubating them with MnCl2 at a low concentration reversed the effect of somatostatin and α2‐agonists. These results suggest that somatostatin and norepinephrine could selectively modulate the renal effect of vasopressin, via the inhibitory regulatory subunit (Ni) of adenylate cyclase.
Use of fluoride ion as a probe for the guanine nucleotide‐binding protein involved in the phosphoinositide‐dependent neutrophil transduction pathway
Authors: Strnad Colette F. , Parente Janice E. , Wong Kenneth
Published: July 2002

Fluoride activation of neutrophils was found to be associated with phosphoinositide turnover, as monitored by the time‐dependent accumulation of inositol phosphates. Unlike phosphoinositide turnover induced by the chemotactic peptide, formylmethionylleucylphenylalanine, that induced by fluoride was not inhibited by pretreatment with pertussis toxin. The translocation of protein kinase C activity from the cytosolic to the membrane compartment was also observed in fluoride‐stimulated cells. We have proposed that the mode of action of this halide ion involves interaction with a GTP‐binding protein which serves as an intermediary unit between the receptors for inflammatory sttimuli and the phosphoinositide‐specific phosphodiesterase.
Processing of precursor tRNAs in a chloroplast lysate
Authors: Yamaguchi-Shinozaki Kazuko , Shinozaki Kazuo , Sugiura Masahiro
Published: July 2002

An in vitro tRNA processing system using either a spinach or tobacco chloroplast lysate has been constructed. Monomeric tRNAPhe precursors were prepared using an SP6 transcription vector system. tRNA precursors were processed to mature tRNA molecules by incubation in an S30 fraction of a chloroplast lysate. Both 5′ leader and 3′ extension sequences were processed endonucleolytically. Processing of the 5′ leader was demonstrated to precede 3′‐end maturation. RNase P‐like endoribonuclease is likely to function in the 5′‐end processing.