bluuebunny/crossref_metadata_2025 huggingface dataset:
Pustulosis exantemática generalizada aguda inducida por meropenem
Authors: Coras Natalia , Pulido Alfredo , Rodríguez Cindy
Published: December 2019

Presentamos el caso de una paciente mujer de 91 años, hospitalizada por infección de herida operatoria secundaria a cirugía de cadera. Se administró tratamiento antibiótico con meropenem, presentando a los 4 días: fiebre, astenia y una erupción eritematosa diseminada con pústulas no foliculares a predominio de tronco, extremidades y áreas de pliegues; además, se observó leucocitosis con neutrofilia. Al estudio histopatológico de biopsia de piel, se evidenciaron pústulas subcorneales con exocitosis de neutrófilos. Se suspendió antibiótico, con mejoría clínica a los 5 días posteriores de la suspensión de meropenem. Existen pocos reportes de casos de pustulosis exantemática generalizada aguda producido por meropenem.
Prácticas y conocimientos sobre prevención primaria de tuberculosis en estudiantes universitarios de ciencias de la salud en la región Tacna, Perú
Authors: Quispe-Prieto Silvia , Caipa-Ramos Manuel , Salas-Hallasi Solange , Salvador-Oré Karen , Romani Franco
Published: December 2019

Introducción. La tuberculosis (TB) es un riesgo laboral para los trabajadores y estudiantes de salud. Objetivo. Describir las prácticas y conocimientos sobre prevención primaria de TB en estudiantes de ciencias de la salud, e identificar los factores asociados a las prácticas de prevención. Métodos. Estudio transversal en estudiantes del penúltimo año de cuatro universidades de Tacna. En 2018, aplicamos un cuestionario de 16 preguntas sobre conocimientos y 13 sobre prácticas de prevención en TB. Realizamos un análisis descriptivo para prácticas y conocimientos, además los factores asociados al puntaje de prácticas fueron determinados con un análisis de regresión lineal. Resultados. Participaron 264 estudiantes. 60,3% refiere que siempre usa el respirador N95 cuando interactúa con pacientes con TB. La carrera universitaria (β: -1,23, IC95%: -1,98 a -0,48) y el antecedente de prácticas en servicios de emergencia (β: 3,08, IC95%: 0,618 a 5,541) estuvieron asociados a prácticas de prevención. Conclusión. Existe una importante brecha en los conocimientos y prácticas sobre prevención primaria en TB en estudiantes antes de ingresar al internado.
La ejecución presupuestal de ESSALUD del Perú como un instrumento de gestión
Authors: Yactayo Chávez Elsa Luz
Published: December 2019

El modelo actual de Gestión Presupuestaria del Seguro Social de Salud en el Perú - ESSALUD, según normas y procedimientos vigentes que regulan su operatividad, no está articulada a la producción de las Metas de Servicios de Salud; actividades que a pesar de estar orientados hacia un mismo objetivo no tienen un punto de convergencia, lo que limita la realización de un análisis integral del comportamiento de la producción de los servicios de salud y la utilización de los recursos presupuestales que materializan su ejecución; dificultando esta situación, la optimización de la asignación y perfeccionamiento del uso de los recursos presupuestales, y con ello, la eficiencia y la calidad de la prestación de servicios de salud. Por lo tanto, surge la necesidad de replantear el esquema presupuestal actual a un nuevo modelo presupuestario como el de Presupuesto por Resultados impulsado por el Estado actualmente. Esta alternativa corregiría los vacíos del presupuesto tradicional, mediante la articulación de Producto y Resultado, aplicando criterios de eficiencia y equidad, lo que ocasionaría cambios significativos en el manejo de la gestión presupuestal de ESSALUD.
A Compreensão e a Vivência da Santidade em Dom Helder Camara Breves apontamentos
Authors: Rampon Ivanir Antonio
Published: January 2020

O artigo quer ressaltar que Dom Helder Camara viveu profundamente a santidade, ou seja, ele permitiu que a graça santificante conferida no sacramento do Batismo (e da Ordem) produzisse nele bons frutos para a Igreja e para a humanidade. Depois de observar que Dom Helder zelava pela santidade da “família humana”, mantendo amizades com “santos da terra” e com “santos do céu”, e de mostrar que, ao longo de seu desenvolvimento espiritual, amadureceu a compreensão de santidade, o texto aponta para algumas das principais características da santidade do Servo de Deus e dos Pobres, a saber, uma santidade de “pastor com cheiro de ovelhas”, com “espírito de Vaticano II”, com “audácia profética”, de “intensa mística” e de “compromisso com a libertação dos pobres”. O artigo apresenta de forma notória a sintonia espiritual entre a compreensão e a vivência da santidade por parte de Dom Helder com os ensinamentos da Exortação Apostólica Gaudete et Exsultate, do Papa Francisco
Atualidade brasileira: a democracia substantiva e a pedagogia do oprimido
Authors: Paludo Conceição , Santos Magda Gisela Cruz dos , Taddei Paulo Eduardo Dias
Published: January 2020

Pautados pelo conceito de democracia substantiva, neste artigo, analisamos algumas das dimensões da atual crise econômica, política e social brasileira e, com base em um estudo bibliográfico, explicitamos as principais contribuições das categorias de ‘opressão’ e ‘educação libertadora’ cunhadas por Freire. O estudo demonstrou que as referidas categorias contribuem para a análise crítica da atualidade brasileira e, portanto, para a efetivação de processos de ‘contrainternalização’ da ordem burguesa, como define Mészáros (2008). Com isso, concluímos que a obra de Freire, especialmente por meio das categorias de ‘opressão’ e ‘educação libertadora’, apresenta uma importância significativa para a consolidação de processos educativos que contribuam com o aprofundamento de uma democracia substantiva (MÉSZÁROS, 2015), um elemento fundamental à superação da sociabilidade fundada na exploração de uma classe por outra.
Reindustrialization of the economy as a basis of industrial policy of Russia
Authors: Masyutin S. A. , Zhivotovskaia A. G.
Published: January 2020

The article discusses the process of de-industrialization of the Russian economy. Particular attention is paid to the most affected branch of engineering – machine-tool industry, its dominant role in the development of production of means of production. The definition of reindustrialization policy as an industrial policy aimed at modernization and innovative development of the country’s economy is given. The process of re-industrialization is considered as the basis of industrial policies of the United States and several European countries. Among the analyzed countries, the authors distinguish Germany, which has retained its industrial potential. A comparative analysis of the industrial sector in Germany and Russia is given. The article analyzes the industrial policy of Germany: «Standort» policy, the transition to the policy of «green» growth, the introduction and implementation of the concept of Industry 4.0. Recommendations on application of tools and measures of industrial policy in Russia are given. The structure of foreign trade is analyzed; estimations of development of economy and industry of Germany and Russia are calculated. The dynamics of the share of employment in the industrial sector of Germany and Russia is given. Taking into account the peculiarities of the industrial policy of Germany, recommendations are made that can be taken into account in Russia’s industrial policy. The emphasis is placed on the development of the national industrial sector as one of the strategic priorities. It is concluded that reindustrialization is one of the means to ensure the accelerated development of the Russian economy and should become the basis of its industrial policy.
Actual problems of developing a mentoring system at industrial enterprises in Russia
Authors: Loktyukhina N. V. , Nazarova Ul. A. , Shabaeva S. V.
Published: January 2020

The authors prove that in modern conditions the demand for such personnel technology as mentoring in the workplace is growing. The reasons underlying this are as follows: the mentoring system cost is less than the traditional methods of staff development (training, retraining, participation in seminars, etc.); retirement age increasing and the federal project implementation «older generation», contributing to the transition of older workers to the mentors category; theory development of the mirror neurons, «reverse mentoring» phenomenon, etc. Actual problems of the mentoring system development at Russian industrial enterprises are examined and solution directions are substantiated. One of the key proposals is the designing of mentoring training systems, which includes a competency level (soft skills development) and a technological level (professional mentors training in systems similar to TWI). The events on the exchange of experience of mentoring, motivation of mentors, providing for moral motivation (through raising the status of a mentor) and material motivation are justified. It is proposed to develop and adopt a professional standard in the field of mentoring, as well as develop a regulatory legal framework in the field of mentoring (changes in labour legislation, provisions of social partnership agreements, guidelines for mentoring, local acts of enterprises).
Online resources and software for teaching and learning Latin
Authors: Balalaieva Olena
Published: January 2020

ABSTRACT: The aim of this article is to review electronic resources in Latin, analyzing their didactic potential to help Classical teachers to effectively organize the educational process, diversifying the set of tools, and enhancing their work. Today, most of the useful links are accumulated on domestic professional sites devoted to the study of Latin. Many foreign scientists and teachers simply do not know about their existence. From time to time, attempts are made to summarize information and provide content for studying Classic languages in scientific publications, but such information quickly becomes outdated and needs to be regularly updated. This article provides an overview of the current most popular resources on Latin: digital libraries and databases, online courses, electronic textbooks, dictionary, translators etc.; describing the current state of the development of e-learning tools and websites for the study of Latin in Ukraine.

KEYWORDS: electronic educational resources; online resources; language learning; Latin language.

 

RESUMO: O objetivo do artigo é revisar recursos eletrônicos em Latim, analisando seu potencial didático para ajudar os professores clássicos a organizar efetivamente o processo educacional, diversificando o conjunto de ferramentas e aprimorando o seu trabalho. Hoje, a maioria dos links úteis é acumulada em vários sites domésticos dedicados ao estudo do Latim. Muitos cientistas e professores estrangeiros simplesmente não sabem sobre sua existência. De tempos em tempos, são feitas tentativas de resumir informações e fornecer conteúdo para o estudo de línguas clássicas em publicações científicas, mas essas informações rapidamente ficam desatualizadas e precisam ser atualizadas regularmente. Este artigo fornece uma visão geral dos recursos mais populares da atualidade em Latim: bibliotecas digitais e bancos de dados, cursos online, livros eletrônicos, dicionário, tradutores etc.; descreve o estado atual de desenvolvimento das ferramentas de e-learning e sites para o estudo do Latim na Ucrânia.

PALAVRAS-CHAVE: recursos educacionais eletrônicos; recursos online; aprendizagem de línguas; língua latina.
Restoran Seçimi Kriterlerinin Müşteri Sadakatine Etkisi: Mersin’de Bir Araştırma
Authors: AKGÜNDÜZ Yılmaz , AKDAĞ Gürkan , METİN Uğurcan
Published: January 2020

Sadık müşteriler, restoranların rekabet gücünü pozitif olarak etkilemektedir. Bu araştırmanın amacı restoran seçim faktörlerini ve bu faktörlerin müşterilerin sadakatleri üzerindeki etkisini belirlemektedir. Bu kapsamda Müşteri Sadakat Ölçeği, Müşteri Restoran Seçim Ölçeği ve demografik sorulardan oluşan bir anket formu kolayda örnekleme yöntemi ile 6 Nisan – 5 Mayıs 2017 tarihleri arasında uygulanmış ve 387 adet geçerli anket toplanmıştır. Ölçeklerin geçerliliği keşfedici faktör analizi ile güvenirlikleri ise Cronbach Alpha değerleri ile belirlenmiştir. Araştırma hipotezi çoklu regresyon analizi ile test edilmiştir. Bulgular restoran seçim faktörlerinin restoran özellikleri, kolaylıklar, menü, servis, personel kalitesi, sipariş ve yiyeceklerden oluştuğunu göstermektedir. Ayrıca araştırma sonuçlarına göre sadece restoran özellikleri ve kolaylıkların müşterilerin sadakati üzerinde pozitif etkiye sahiptir.
Geç Kapitalist Dönemde Başarı-Başarısızlık: Dizi Gerçekliği
Authors: AKKOÇ Aslıhan
Published: January 2020

Bu çalışmayla başarı ve başarısızlığın toplumsal boyutlarını tartışmak amaçlanmaktadır. Geç kapitalist dönemde, modern ilişkiler sistemi içinde insanlar toplumsal ve toplumlar arası koşullardan büyük oranda etkilenmektedirler. Özellikle de geç kapitalist dönemde küresel, toplumsal, iktisadi ve kültürel unsurlardan insanlar büyük ölçüde etkilenmektedirler. Pek çok şey gibi, kişisel başarı-başarısızlık da toplumsal koşullarla yakından ilişkilidir. Bir diğer açıdan da başarı, toplum tarafından insanlara atfedilen bir sıfattır. Başarı hem toplumda kazanılan bir şeydir, hem de bireysel koşulların ürünü olmanın yanında toplumsal koşullarla da ilişkilidir. Bunun yanında, geç kapitalist dönemin başarı algısı dikkat çekmektedir. Bu bağlamda televizyon dizilerinde aktarılan başarı algısını incelemek amaçlanmıştır. Çalışmanın kapsamı, bir televizyon dizisinde yer alan başarı sunumunun incelenmesi ve bunun yanında geç kapitalist koşullarda başarının toplumsal koşullar ile ilişkisi üzerine olacaktır.
Gazete Haberlerini Konu Alan Yüksek Lisans Tezlerine Dair Bibliyometrik Bir Analiz
Authors: PELİVAN Mehmet
Published: January 2020

Bilginin geçmişi ve geleceği ile ilgili iki temel yaklaşımdan ilki, bilginin birikimli bir şekilde ilerlediği ve yapılacak çalışmaların geçmişteki bilgiden yararlanarak gelişme sağlayacağı fikrine dayanmakta ve günümüzde güçlü bir şekilde kabul görmektedir. İkinci olarak ise varolan bilginin yıkılarak yenilerinin inşa edileceği, gelişmelerin sağlanacağı kabulüdür ve birinci yaklaşımın tam karşısına konumlanmaktadır. Özellikle bazı kuramsal yaklaşımların, varolan bilgiyi tamamen ortadan kaldırarak kurulduğu hatırlandığında bu bakış açısının da önemli bir kapsayıcılığı olduğu kabul edilmelidir. Bilgiyle ilgili her iki yaklaşımda da bir alanı, konuyu ya da literatürü ele alan çalışmaların bütünlüklü bir değerlendirilmesi kaçınılmazdır. Kısacası bir kuramsal anlayışı yıkmak ya da doğrulamak için ilgili literatüre kapsamlı bir şekilde hâkim olmak ve literatürü tartışmak ihtiyacı her zaman vardır. Bu çalışmada da Türkiye'de gazete haberlerini konu alan ve dolaylı ya da doğrudan ideoloji tartışması yapan yüksek lisans tezlerinin, değerlendirme için gerekli literatürü oluşturduğu varsayımından hareketle söz konusu çalışmaların yıl ve üniversite bağlamında dağılımlarını ve değişimlerini ortaya koymak amaçlanmıştır. Bu amaç doğrultusunda üniversite ve yıl başlıkları altında çalışmaların, anabilim dallarına, konularına, kuramsal yaklaşımlarına, yöntemlerine, hipotezlerine ve inceledikleri gazetelerin kapsamına göre nasıl dağılım ve değişim gösterdiği sorularına cevap aranmıştır. Sorulara cevap bulmak için bibliyometrik çözümleme yöntemi kullanılmış, nicel olarak toplanan veriler, tablolar şeklinde sunulmuş ve incelenmiştir.
Goebbels Liderliğinde Nazi Almanyası'nda Propaganda Sineması
Authors: ÇAKI Caner , GAZİ Mehmet Ali , ÇAKI Gül , ALMAZ Fulya
Published: January 2020

Nasyonal Sosyalist Alman İşçi Partisi'nin (NSDAP) 30 Ocak 1933 tarihinde iktidara gelmesi ile birlikte Almanya'da Halkı Aydınlatma ve Propaganda Bakanlığı kurulmuştu. NSDAP lideri Adolf Hitler, kurulan bu yeni bakanlığın başına partisinin önde gelen isimlerinden Joseph Goebbels'i getirmişti. Goebbels, bakanlığın başına geçtikten kısa bir süre sonra ülkedeki tüm medya kuruluşları üzerinde sıkı bir denetim kurma yoluna gitmişti. Goebbels, medya üzerinde kurulan sıkı denetim sayesinde, ülkedeki tüm kitle iletişim araçlarını Nazi rejiminin propaganda faaliyetleri için kullanmayı hedeflemişti. Özellikle bu aşamada sinema, Goebbels'in en önemli propaganda araçlarından bir haline gelmişti. Goebbels, Nazizm ideolojisinin kitleler üzerinde tahakküm kurabilmesinde sinemanın etkili bir propaganda aracı olacağına inanmıştı. Bundan dolayı Goebbels, propaganda bakanı olarak görev aldığı 12 yıl boyunca (1933-1945), Almanya'da dünya tarihinin en etkili propaganda filmlerinin çekilmesini sağlamıştı. Çalışmada Goebbels'in bakanlığı döneminde Almanya'da sinema sektörünün gelişim süreci, uygulanan sansürler, boykotlar, yaşanan krizler, devlet teşvikleri ve Nazi rejimi tarafından çekilen propaganda filmleri detaylı bir şekilde açıklanmaya çalışılmıştır. Çalışma kapsamında propaganda sinemasının dönüm noktalarından biri olan Goebbels liderliğindeki Alman sinemasına ışık tutulması amaçlanmıştır.
İmalat İşletmelerinde Bilgi Yönetimi ile Performans Arasındaki İlişkide Sosyal Sermayenin Rolü
Authors: YILMAZ Celal
Published: January 2020

Bu çalışmanın amacı bilgi yönetimi ile işlevsel ve finansal performans arasındaki ilişkide sosyal sermayenin aracılık rolünü ortaya koymaktır. Bununla birlikte değişkenler arasındaki ilişkillerin varlığının belirlenmesi amaçlanmıştır. Araştırmanın örneklemini Konya ili imalat işletmelerinde görev yapan 412 çalışan oluşturmaktadır. Bu doğrultuda yapısal eşitlik modeli (YEM) yöntemi ile veriler analiz edilmiştir. Araştırmanın bulguları değişkenler arasında pozitif ilişkilerin olduğunu ortaya koyarken, sosyal sermayenin bilgi yönetimi ile işlevsel performans ve finansal performans arasındaki ilişkide aracılık etkisine sahip olmadığını göstermektedir. Çalışmada birtakım teorik ve yönetsel çıkarımlarla birlikte çalışmanın sınırlılıkları ve gelecek araştırmalara dair öneriler sunulmaktadır. Çalışmanın temel teorik çıkarımı, bilgi yönetimi uygulamalarının sosyal sermayeyi istikrara kavuşturup işlevsel ve finansal performansı artırma üzerinde ciddi bir rol oynadığı yönündedir. Temel yönetsel çıkarım ise uygulayıcıların bilgi yönetimini işletmeyi geleceğe hazırlama sanatı ve bilimi olarak ele almaları ve sosyal sermayeye nitel ve nicel yatırım yapmaları gerektiği doğrultusundadır.
Mobilization of intracellular calcium by intracellular flash photolysis of caged dihydrosphingosine in cultured neonatal rat sensory neurones.
Authors: Ayar A , Thatcher N M , Zehavi U , Trentham D R , Scott R H
Published: January 2020

The ability of dihydrosphingosine to release Ca2+ from intracellular stores in neurones was investigated by combining the whole cell patch clamp technique with intracellular flash photolysis of caged, N-(2-nitrobenzyl)dihydrosphingosine. The caged dihydrosphingosine (100 microM) was applied to the intracellular environment via the CsCl-based patch pipette solution which also contained 0.3% dimethylformamide and 2 mM dithiothreitol. Cultured dorsal root ganglion neurones from neonatal rats were voltage clamped at -90 mV and inward whole cell Ca2+-activated currents were recorded in response to intracellular photorelease of dihydrosphingosine. Intracellular photorelease of dihydrosphingosine (about 5 microM) was achieved using a Xenon flash lamp. Inward Ca2+-activated currents were evoked in 50 out of 57 neurones, the mean delay to current activation following photolysis was 82+/-13 s. The responses were variable with neurones showing transient, oscillating or sustained inward currents. High voltage-activated Ca2+ currents evoked by 100 ms voltage step commands to 0 mV were not attenuated by photorelease of dihydrosphingosine. Controls showed that alone a flash from the Xenon lamp did not activate currents, and that the unphotolysed caged dihydrosphingosine, and intracellular photolysis of 2-(2-nitrobenzylamino) propanediol also did not evoke responses. The dihydrosphingosine current had a reversal potential of -11+/-3 mV (n = 11), and was carried by two distinct Cl- and cation currents which were reduced by 85% and about 20% following replacement of monovalent cations with N-methyl-D-glucamine or application of the Cl- channel blocker niflumic acid (10 microM) respectively. The responses to photoreleased dihydrosphingosine were inhibited by intracellular application of 20 mM EGTA, 10 microM ryanodine or extracellular application of 10 microM dantrolene, but persisted when Ca2+ free saline was applied to the extracellular environment. Intracellular application of uncaged dihydrosphingosine evoked responses which were attenuated by photolysis of the caged Ca2+ chelator Diazo-2. Experiments also suggested that extracellular application of dihydrosphingosine can activate membrane conductances. We conclude that dihydrosphingosine directly or indirectly mobilises Ca2+ from ryanodine-sensitive intracellular stores in cultured sensory neurones.
Contents of total and protein-bound carbohydrates are low in leukemic leukocytes from patients with acute myelogenous leukemia.
Authors: Smoleńska-Sym G , Zdebska E , Gołaszewska E , Woźniak J , Durzyński T , Maj S , Mokras U , Kościelak J
Published: January 2020

Leukemic leukocytes from 12 patients with acute myelogenous leukemia (AML) and two patients with chronic myelogenous leukemia (CML) were isolated by centrifugations in Percoll gradients, and examined for total carbohydrates. In leukemic leukocytes from 10 of these patients ceramide-bound carbohydrates were also determined. Protein-bound carbohydrates were calculated by subtraction of ceramide-bound carbohydrates from total carbohydrates. In all samples analysed the contents of total and protein-bound carbohydrates were much lower in leukemic leukocytes than in normal neutrophils, irrespective whether the results were expressed relative to protein, DNA, cell number or dry mass. For immature leukemic cells of M0-M1 phenotype differences up to 10-fold were observed. Contents of ceramide-bound carbohydrates, i.e. those of neutral and acidic glycosphingolipids (GSLs) were also low in leukemic cells. However, when GSL carbohydrates were calculated as percentage of total carbohydrates, GSLs in leukemic leukocytes were elevated in half of the AML patients but depressed in the other half. The results are discussed in the light of the hypothesis on GSL function by one of us (Kościelak J., 1986, Glycoconjugate J. 3, 95-108). According to one element of the hypothesis, during cell differentiation newly synthesized glycoproteins (GPs) that perform specific functions are added to house-keeping GPs that are present in plasma membranes of all types of cells. Thus, during differentiation, the GP content of the cell membrane should increase and that of the so called "membrane packing" glycosphingolipids should decrease.
Photochemical labeling of HL-60 cell membrane proteins with radioiodinated, 4-azidosalicylic acid acylated derivatives of gangliosides.
Authors: Pacuszka T , Panasiewicz M , Hoser G , Kawalec M
Published: January 2020

To detect HL-60 human promyelocytic leukemia cell proteins involved in the uptake of gangliosides from the culture medium we used photoreactive, 4-azidosalicylic acid (ASA) acylated and radioiodinated (200 Ci/mmole) derivatives of GM3, GD3, GM1, and FucGM1 gangliosides. Gangliosides-ASA, added to the medium at 15-20 nM concentration, followed a similar time course of uptake. After 1 min incubation cell bound gangliosides-ASA could not be removed with trypsin, but only 5-10% remained after incubation with BSA. The proportion of cell bound gangliosides-ASA resistant to BSA treatment increased with time of incubation up to 76% after 20 h. As shown on TLC, GM3- and GD3-ASA were catabolized to LacSph-ASA and ceramide-ASA, while GM1-ASA was hydrolyzed to GM2-ASA. FucGM1-ASA was converted to GM1-ASA very slowly. Upon irradiation with UV lamp, cell bound gangliosides-ASA crosslinked to and photolabeled many proteins but the distribution of radioactivity after SDS/PAGE was very uneven and did not correlate with Coomassie staining. In all experiments the 42 kDa protein bands were most intensely photolabeled. Photolabeling of 42 kDa proteins decreased with time of incubation as compared to lower molecular mass pro teins. With all gangliosides-ASA used similar but not identical protein photolabeling patterns were obtained. Photolabeling patterns with GM3- and GD3-ASA differed from those with GM1- and FucGM1-ASA.
Purification and characterization of avian glycolipid: beta-galactosyltransferases (GalT-4 and GalT-3): cloning and expression of truncated betaGalT-4.
Authors: Basu S S , Dastgheib S , Ghosh S , Basu M , Kelly P , Basu S
Published: January 2020

Acidic glycolipid of ganglio-(containing sialic acid) and sialyl-lactofucosyl-type, SA-Lex (containing sialic acid and fucose) are developmentally regulated and appear to be ubiquitous on neuronal and cancer cell surfaces of animals. Two glycolipid: beta-galactosyltransferases, GalT-3 and GalT-4, were characterized in embryonic chicken brain (ECB). Based on substrate competition experiments, these two activities were believed to be due to expression of two gene products. A cDNA fragments (about 600 bp) encoding the catalytic domain of the GalT-4 (UDP-Gal:LcOse3Cer beta1,4galactosyltransferase) from ECB and human Colo-204 were isolated. These cDNAs were expressed as a soluble glutathione-S-transferase fusion protein (48 kDa) in Escherichia coli. Interactions between GlcNAc-, UDP-hexanolamine-, and alpha-lactalbumin were studied with the purified fusion protein (recombinant and truncated). Functionally it was similar to that of native GalT-4 purified (40000-fold) from 11-day-old ECB. GalT-3 (UDP-Gal:GM2beta1,3galactosyltransferase) was purified from 19-day-old ECB, and a polyclonal antibody was produced against the peptide backbone for immunoscreening of a lambdaZAP ECB cDNA expression library. Each of the GalT-3 peptides (62 and 65 kDa was analyzed by protein fingerprinting analysis indicating a similar peptide mapping pattern.
Distinct roles for sphingolipids and glycosphingolipids at different stages of neuronal development.
Authors: Futerman A H
Published: January 2020

Studies on the roles of sphingolipids (SLs) and glycosphingolipids (GSLs) at distinct stages of neuronal development have been performed using primary cultures of hippocampal neurons, which are unique among neuronal cultures inasmuch as they develop by a well-characterized and stereotypic sequence of events that gives rise to fully differentiated axons and dendrites. Our data demonstrate that SLs and GSLs play at least three distinct roles in regulating neuronal development, namely: (i) ceramide enhances the formation of minor neuronal processes from lamellipodia and the subsequent stage of axonogenesis; (ii) glucosylceramide synthesis, but not the synthesis of higher-order GSLs, is required for normal axon growth and for accelerated axonal growth upon stimulation by growth factors; and (iii) at both of these stages, ceramide at high concentrations can induce apoptotic cell death. Together, these observations are consistent with the possibility that minor process formation and apoptosis are regulated by ceramide-dependent signaling pathways, whereas axonal growth requires glucosylceramide synthesis, perhaps to support an intracellular transport pathway.
Photochemical labeling of human erythrocyte membrane proteins with radioiodinated 4-azidosalicylic acid derivatives of G(M3), G(D3), G(M1), and FucG(M1) gangliosides.
Authors: Pacuszka T , Panasiewicz M
Published: January 2020

Photoreactive gangliosides of high specific radioactivity may prove useful for studies on glycosphingolipid functions. We prepared 4-azidosalicylic acid (ASA) acylated derivatives of GM3, GD3, GM1, and FucGM1 gangliosides (gangliosides-ASA). Gangliosides-ASA were characterized by their TLC mobility, UV spectra, carbohydrate composition, and digestion with leech endoceramidase. After radioiodination to about 200 Ci/mmole gangliosides-ASA were used for photochemical labeling of human erythrocytes. Radioiodinated gangliosides-ASA were incorporated into erythrocytes in a time and concentration dependent manner, the kinetics and extent of incorporation being similar for all the gangliosides-ASA used. Radioiodinated gangliosides-ASA incorporated into erythrocytes were resistant to trypsin digestion while treatment with 1% BSA removed about 90% of the label. Incubation with cholera toxin protected radioiodinated GM1-ASA and, to a lesser extent, FucGM1-ASA but not GM3-ASA and GD3-ASA, against removal with BSA. After photolysis about 40-50% of radioactivity was firmly bound to erythrocyte lipids and proteins. The ratio of lipid- to protein-bound radioactivity ranged from 2.2:1 to 3.2:1. Photolabeled proteins were analyzed by SDS/PAGE followed by autoradiography. Band 3 was the most extensively photolabeled protein with all the radioiodinated gangliosides-ASA used. DIDS, an inhibitor of band 3 protein activity, caused reduction in photolabeling of this protein by about 20%.
Endogenous and exogenous DNA lesions recognized by N-alkylpurine-DNA glycosylases.
Authors: Borys E , Kuśmierek J T
Published: January 2020

The combined action of glycosylases and abasic site-specific endonucleases on damaged bases in DNA results in single strand breaks. In plasmid DNA, as a consequence, the covalently closed circular (ccc) form is converted to the open circular (oc) form, and this can be quantitated by agarose gel electrophoresis. We studied DNA lesions sensitive to E. coli 3-methyladenine-DNA glycosylase II (AlkA) and cloned human N-alkylpurine-DNA glycosylase (ANPG-40) which are known to excise alkylated bases and etheno adducts. pBR322 and pAlk10 plasmids not pretreated with mutagens were cleaved by both glycosylases in the presence of enzymes possessing endonucleolytic activity, which indicates that plasmids contain unknown, endogenously formed adducts. Plasmids pretreated with chloroacetaldehyde, a mutagen forming etheno adducts, exhibited enhanced sensitivity to both glycosylases. Adducts formed by acrolein and croton aldehyde were excised by AlkA, but not by ANPG-40, whereas malondialdehyde adducts were not excised by either glycosylase. Bulky p-benzochinone adducts were not excised by AlkA, however, the plasmid pretreated with this mutagen was incised by endonucleases, possibly without prior generation of an abasic site. These examples show that examination of conformational changes of plasmid DNA can be taken advantage of to study the specificity of N-alkylpurine-DNA-glycosylases.
Template-directed base pairing of 2-chloro-2'-deoxyadenosine catalyzed by AMV reverse transcriptase.
Authors: Bukowska-Maciejewska A M , Kuśmierek J T
Published: January 2020

2-Chloro-2'-deoxyadenine (2CldA) is used for treatment of several lymphoid malignancies. Since this drug is incorporated into DNA, we have undertaken studies on base pairing of 2-chloroadenine (2ClA). 2CldA phosphoramidite was synthesized and used for preparation of 25-mer templates with 2ClA located at site 21 from the 3'-end. Kinetic parameters (Km and Vmax) for the incorporation of deoxynucleoside-5'-triphosphates by AMV reverse transcriptase opposite the 2ClA template, as well as for the extension of 2ClA.T pair, were determined. The efficiency (Vmax/Km) of incorporation of dGTP, dCTP, and dATP opposite 2ClA is at least one order of magnitude lower than opposite unmodified A. The efficiency of incorporation of dTTP opposite 2ClA is about 30-fold lower than opposite A and extension of 2ClA.T pair is 3-fold lower than of A.T pair. From the analysis of the parameters of dTTP incorporation we conclude that formation of 2ClA.T pair is thermodynamically, but not kinetically controlled. The difference in binding energy (deltadeltaG) between 2ClA.T and A.T pairs in the environment of the polymerase active site is 2 kcal/mol. Our results indicate that the presence of 2ClA in DNA slows down replication, but does not lead to base-substitution mutations.
Reconstitution of UV-damaged DNA into chromatin using Xenopus oocyte extracts.
Authors: Widłak P
Published: January 2020

Chromatin was reconstituted in vitro using Xenopus oocyte extracts and plasmid DNA containing UV radiation-induced damage. Damaged DNA was assembled into minichromosomes with an efficiency similar to that of control, non-irradiated DNA. Oocyte extracts were competent to carry out DNA repair, which was elicited by nicking damaged templates followed by DNA synthesis during chromatin assembly. Newly synthesized DNA was efficiently reconstituted into nucleosomes.
Modified RNAs as potential drug targets.
Authors: Guenther R , Forrest B , Newman W , Małkiewicz A , Agris P F
Published: January 2020

Bleomycin (BLM) is a natural antibiotic that is effective in treatment of selected cancers. Although the exact therapeutic mechanism of bleomycin is not known, its target is thought to be a nucleic acid. Besides cleaving DNA, in vitro, Fe-bleomycin cleaves the anticodon of yeast tRNA(Phe) specifically. Using CD and fluorescence spectroscopy we have found that apo-bleomycin binds to synthetic RNA analogs of the anticodon of yeast tRNA(Phe) with an affinity similar to that previously reported for DNA. In order to understand BLM's selectivity, the role magnesium ions play in RNA recognition should be explained. Many RNA substrates for Fe-BLM, including yeast tRNA(Phe), are not cleaved by the drug when the Mg2+ concentration exceeds 1 mM. Competition experiments with anticodon analogs provide insight into the role of magnesium ions in RNA recognition by BLM. These simple modified RNAs may be useful as model systems for investigating BLM/RNA recognition and development of highly selective drugs toward RNA targets.
The induction of cytochrome P450 isoform, CYP4A1, by clofibrate coincides with activation of ethanolamine-specific phospholipid base exchange reaction in rat liver microsomes.
Authors: Lenart J , Komańska I , Jasińska R , Pikuła S
Published: January 2020

Administration of a hypolipidaemic drug, clofibrate, to rats resulted, 24 h after a single intraperitoneal injection (250 mg/kg body weight), in pronounced enhancement of the rate of phosphatidylethanolamine (PE) synthesis via the PE-specific base exchange (PEBE) reaction in liver microsomes. This was accompanied by 3.4-fold activation of microsomal omega-hydroxylation of lauric acid by cytochrome P450 4A1 isoform (CYP4A1) and an increase in the protein content of this isoform in endoplasmic reticulum (ER) membranes. Since PE represents a class of phospholipids (PL) prerequisite for proper functioning of CYP4A1, and the PEBE reaction is an inducible pathway of PL synthesis in hepatocytes under metabolic stress, one may speculate that this reaction is switched on when extensive remodelling of PL molecular species or/and massive synthesis of lipid bilayer components for membrane assembly is required.
Use of repair endonucleases for characterization of DNA damage induced by N-heterocyclic aromatic hydrocarbons.
Authors: Gábelová A , Bacová G , Slamenová D , Périn F
Published: January 2020

Several repair endonucleases were used to characterize and quantify various types of DNA damage induced by 7H-dibenzo[c,g]carbazole (DBC) and its methyl derivative, N-methyldibenzo[c,g]carbazole (MeDBC). Differences in the DNA damage profile induced by these two derivatives were found to be related to their chemical structure and dependent on the way of their metabolic activation. Different ways of activation gave rise to different numbers of single strand breaks and DNA modifications or, at least, to different ratios of common modifications. DBC induced the highest level of breaks in human hepatal cell line Hep G2, while MeDBC induced most of the breaks in V79 cell line with stable expression of human cytochrome P4501A1. Our results support the idea of two different pathways of biotransformation of DBC and MeDBC.
Nucleosomes and regulation of gene expression. Structure of the HIV-1 5'LTR.
Authors: Widłak P , Garrard W T
Published: January 2020

Packaging of DNA into chromatin adds complexity to the problem of regulation of gene expression. Nucleosomes affect the accessibility of transcription factors to occupy their binding sites in chromatin of eukaryotic cells. The disruption of nucleosome structure within the enhancer/promoter region of the integrated HIV-1 proviral genome is an instructive example of a chromatin remodeling process during transcriptional activation. To investigate the mechanism responsible for generating nuclease hypersensitive sites that exist in vivo in the promoter/enhancer region of the 5'LTR (long terminal repeat) of integrated HIV-1 we have utilized an in vitro chromatin assembly system with Xenopus oocyte extracts. Chromatin assembly in the presence of Sp1 and NFkappaB transcription factors induces DNase I hypersensitive sites on either side of their binding sites and positions the adjacent nucleosomes. This structure can also be formed in a factor-induced, ATP-dependent chromatin remodeling process and closely resembles the in vivo chromatin structure. The DNase I hypersensitive sites that form within the HIV LTR are probably histone-free and remain after removal of transcription factors.
Binding of SPXK- and APXK-peptide motifs to AT-rich DNA. Experimental and theoretical studies.
Authors: Brzeski J , Grycuk T , Lipkowski A W , Rudnicki W , Lesyng B , Jerzmanowski A
Published: January 2020

The binding properties of the SPXK- and APXK-type peptides to the AT-rich DNA fragments of different length were studied by measuring the competition of peptides with Hoechst 33258 dye for DNA binding and by the gel shift assay analysis. In parallel to the experimental studies, molecular modeling techniques were used to analyze possible binding modes of the SPXZ and APXK motifs to the AT-rich DNA. The results of the competition measurements and gel shift assays suggest that serine at the i-1 position (i is proline) can be replaced by alanine without affecting the binding properties of the motif. Thus, the presence of the conserved serine in this motif in many DNA-binding proteins is probably not dictated by structural requirements. Based on the results of molecular modeling studies we propose that the binding mode of the SPXK-type motifs to the AT-rich DNA resembles closely that between the N-terminal arm of the homeodomain and DNA. This model confirms that serine in the SPXK motifs is not essential for the DNA binding. The model also indicates that if X in the motif is glutamic acid, this residue is probably protonated in the complex with DNA.
Mutation in the regulatory region of the EDA gene coincides with the symptoms of anhidrotic ectodermal dysplasia.
Authors: Kobielak K , Kobielak A , Limon J , Trzeciak W H
Published: January 2020

We have investigated a fragment of the regulatory region of the EDA gene in a patient with clinical symptoms of anhidrotic ectodermal dysplasia (EDA), whose DNA sequence of exon 1 was normal. The single-strand conformation polymorphism (SSCP) analysis of PCR-amplified fragments of the regulatory region of the EDA gene suggested a mutation localized within the fragment extending from nucleotide -571 to -182 upstream of the 5' end of the cDNA. Sequence analysis of this fragment documented an additional adenine in position -452, located 32 nucleotides upstream from the response element HK-1, a target for transcription factor LEF-1, involved in the differentiation of tissues of ectodermal and mesodermal origin. We postulate that this mutation might interfere with the transcription process of the EDA gene and might be responsible, at least in part, for the clinical symptoms of anhidrotic ectodermal dysplasia.
Biochemical and genetic analysis of lambdaW, the newly isolated lambdoid phage.
Authors: Wróbel B , Srutkowska S , Wegrzyn G
Published: January 2020

Otherwise isogenic Escherichia coli CP78 (relA+) and CP79 (relA-) strains are commonly used in studies on the stringent control, the bacterial response to amino acid starvation. We found that these strains are lysogenic for a phage which is spontaneously induced with a low frequency, producing virions able to infect other E. coli strains. Genetic studies, restriction analysis of the phage DNA genome, and electron microscopy revealed that this phage is very similar to, but not identical with, bacteriophage lambda. We called the newly isolated phage lambdaW, and found that most of CP78/CP79 ancestor strains are lysogenic for this phage.
Molecular modelling of the vasopressin V2 receptor/antagonist interactions.
Authors: Czaplewski C , Kaźmierkiewicz R , Ciarkowski J
Published: January 2020

We predict some essential interactions between the V2 vasopressin renal receptor (V2R) and its selective peptide antagonist desGly9-[Mca1,D-Ile2,Ile4]AVP, and compare these predictions with the earlier ones for the non-peptide OPC-36120 antagonist- and the [Arg8]vasopressin (AVP) agonist-V2 receptor interactions. V2R controls antidiuresis in mammals and belongs to the superfamily of the heptahelical transmembrane (7TM) G protein-coupled receptors (GPCR)s. V2R was built, the ligands docked and the structures relaxed using advanced molecular modeling techniques. Both the agonist and the antagonists (no matter whether of peptide- or non-peptide type) appear to prefer a common V2R compartment for docking. The receptor amino-acid residues, potentially important in ligand binding, are mainly in the TM3-TM7 helices. A few of these residues are invariant for the whole GPCR superfamily while most of them are conserved in the subfamily of neurohypophyseal receptors, to which V2R belongs. Some of the equivalent residues in a related V1a receptor have been earlier reported as critical for the ligand affinity.
Acyclic analogues of 5-fluoro-dUMP and 5-fluoro-2'-deoxyuridine: synthesis and inhibition of thymidylate synthase and tumour cell growth.
Authors: Felczak K , Gołos B , Dzik J M , Rode W , Bretner M , Shugar D , Kulikowski T
Published: January 2020

1-[(2-Hydroxyethoxy)methyl]-5-fluorouracil (HEMFU) and 1-[(1,3-dihydroxy-2-propoxy)methyl]-5-fluorouracil (DHPFU) were prepared by alkylation of the di-O-TMS derivative of 5-fluorouracil and phosphorylated with the use of the wheat shoot phosphotransferase system to their monophosphates, HEMFUMP and DHPFUMP. 1-(2-Phosphonylmethoxyethyl)-5-fluorouracil (PMEFU) was obtained by condensation of diethyl-2-chloroethoxymethanephosphonate with 5-fluorouracil and cleavage of the alkylphosphoester with trimethylbromosilane. Inhibition of highly purified thymidylate synthase from mouse tumour Ehrlich carcinoma and leukemia L1210 cells by each of the nucleotide analogues, DHPFUMP, PMEFU and HEMFUMP, and of L5178Y mouse leukemia cell growth by the nucleoside (HEMFU) analogue, were studied. DHPFUMP proved to be the strongest inhibitor, non-competitive vs dUMP, with K(i)app 2.8 microM for time-independent interaction with the enzyme and N5,N10-methylenetetrahydrofolate (CH2H4PteGlu). In the presence of CH2H4PteGlu, DHPFUMP exhibited time-dependent inactivation of the enzyme, the inactivation rate plots being biphasic and pointing to Ki values in the microM range (10(3)-fold higher than for 5-fluoro-dUMP). HEMFUMP and PMEFU were much weaker inhibitors of the enzyme, with K(i)app values of 0.26 mM (non-competitive vs dUMP) and 30 mM (non-competitive vs dUMP), respectively. HEMFU, despite the weak interaction of its nucleotide analogue with the enzyme, proved to be a strong cell (L5178Y) growth inhibitor, with IC50 in the range 10(-5) M.
The effect of chemo- and chemoimmunotherapy on the presence of circulating melanoma cells in peripheral blood. Preliminary results.
Authors: Szenajch J , Kozak A , Kruszewski A A , Babiej E , Chomicka M , Struzyna J , Wiktor-Jedrzejczak W
Published: January 2020

Reverse transcription and polymerase chain reaction (RT/PCR) with primers specific for tyrosinase allow for a new method of early detection of individual melanoma cells in peripheral blood. Using this test the effect of chemo- and chemoimmunotherapy on the spread of early micrometastatic cancer cells has been evaluated. No significant correlations have been found between RT/PCR results on the one hand and stage of disease, a kind of the therapy protocol used and usage of the therapy as an adjuvant or palliative on the other hand. Thus, although the RT/PCR test for detection of circulating individual melanoma cells might help in identification of minimal residual disease in some patients, it has no application for routine staging of more advanced disease and in monitoring the response to therapy.
Cloning of the groE operon of the marine bacterium Vibrio harveyi using a lambda vector.
Authors: Kuchanny D , Klein G , Krzewska J , Czyz A , Lipińska B
Published: January 2020

groES and groEL genes encode two co-operating proteins GroES and GroEL, belonging to a class of chaperone proteins highly conserved during evolution. The GroE chaperones are indispensable for the growth of bacteriophage lambda in Escherichia coli cells. In order to clone the groEL and groES genes of the marine bacterium Vibrio harveyi, we constructed the V. harveyi genomic library in the lambdaEMBL1 vector, and selected clones which were able to complement mutations in both groE genes of E. coli for bacteriophage lambda growth. Using Southern hybridization, in one of these clones we identified a DNA fragment homologous to the E. coli groE region. Analysis of the nucleotide sequence of this fragment showed that the cloned region contained a sequence in 71.7% homologous to the 3' end of the groEL gene of E. coli. This confirmed that the lambda clone indeed carries the groE region of V. harveyi. The positive result of our strategy of cloning with the use of the genomic library in lambda vector suggests that the same method might be useful in the isolation of the groE homologues from other bacteria. The V. harveyi cloned groE genes did not suppress thermosensitivity of the E. coli groE mutants.
The Escherichia coli RNA polymerase alpha subunit and transcriptional activation by bacteriophage lambda CII protein.
Authors: Gabig M , Obuchowski M , Ciesielska A , Latała B , Wegrzyn A , Thomas M S , Wegrzyn G
Published: January 2020

Bacteriophage lambda is not able to lysogenise the Escherichia coli rpoA341 mutant. This mutation causes a single amino acid substitution Lys271Glu in the C-terminal domain of the RNA polymerase alpha subunit (alphaCTD). Our previous studies indicated that the impaired lysogenisation of the rpoA341 host is due to a defect in transcriptional activation by the phage CII protein and suggested a role for alphaCTD in this process. Here we used a series of truncation and point mutants in the rpoA gene placed on a plasmid to investigate the process of transcriptional activation by the cII gene product. Our results indicate that amino-acid residues 265, 268 and 271 in the a subunit may play an important role in the CII-mediated activation of the pE promoter (most probably residue 271) or may be involved in putative interactions between alphaCTD and an UP-like element near pE (most probably residues 265 and 268). Measurement of the activity of pE-lacZ, pI-lacZ and p(aQ)-lacZ fusions in the rpoA+ and rpoA341 hosts demonstrated that the mechanism of activation of these CII-dependent promoters may be in each case different.
Accumulation of collagen in ovarian benign tumours.
Authors: Wolańska M , Sobolewski K , Bańkowski E , Drozdzewicz M
Published: December 2019

Extracellular matrix components of benign ovarian tumours (cystadenoma, adenofibroma, cystadenofibroma) were analysed. The investigated tumours contained twice as much collagen than control ovarian tissues. Significant alterations in mutual quantitative relationships between collagens of various types were observed. The proportion of type I collagen decreased and that of type III collagen increased. The accumulation of collagen was accompanied by a reduction in sulphated glycosaminoglycan content whereas the amount of hyaluronic acid was not changed. Dermatan sulphate was the most abundant glycosaminoglycan component. It is suggested that the accumulation of collagen (natural barrier to the migration of tumour cells) and underexpression of glycosaminoglycans/proteoglycans (binding some growth factors and interleukins) may exert an inhibitory effect on tumour growth.