Grammatical comprehension in language and communication disorders.

Autism Spectrum Disorder (ASD) and Developmental Language Disorder (DLD) have traditionally been considered separate disorders, although some similarities and overlaps in certain aspects of language have been detected. In this paper, we compare the deficits in receptive grammar in these two disorders. We analyse the proportion of grammatical errors in relation to semantic complexity in 84 children divided into four groups: children with autism language impairment (ALI), with autism language normal (ALN), with DLD, and with typical development (TD), all groups with the same age of receptive vocabulary. The results show significant differences in the comprehension of grammatical structures, both simple (canonical and non-reversible) and complex (non-canonical and reversible). Children with ASD and DLD show different language profiles depending on the syntactic complexity. In the simplest structures, no differences are found between the groups, starting at an equivalent vocabulary age of 7:8 years. However, there are differences between the ALI and DLD groups with respect to the TD group in the more complex structures, starting at an equivalent vocabulary age of 3 years. Therefore, both groups ALI and DLD present the greatest difficulties compared to ALN and TD. The paper discusses the importance of attending to these differences, since the repercussion of comprehension difficulties increases as children grow.

Genome-wide association analysis for maize stem Cell Wall-bound Hydroxycinnamates.

BACKGROUND: The structural reinforcement of cell walls by hydroxycinnamates has a significant role in defense against pests and pathogens, but it also interferes with forage digestibility and biofuel production. Elucidation of maize genetic variations that contribute to variation for stem hydroxycinnamate content could simplify breeding for cell wall strengthening by using markers linked to the most favorable genetic variants in marker-assisted selection or genomic selection approaches​. RESULTS: A genome-wide association study was conducted using a subset of 282 inbred lines from a maize diversity panel to identify single nucleotide polymorphisms (SNPs) associated with stem cell wall hydroxycinnamate content. A total of 5, 8, and 2 SNPs were identified as significantly associated to p-coumarate, ferulate, and total diferulate concentrations, respectively in the maize pith. Attending to particular diferulate isomers, 3, 6, 1 and 2 SNPs were related to 8-O-4 diferulate, 5-5 diferulate, 8-5 diferulate and 8-5 linear diferulate contents, respectively. This study has the advantage of being done with direct biochemical determinations instead of using estimates based on Near-infrared spectroscopy (NIRS) predictions. In addition, novel genomic regions involved in hydroxycinnamate content were found, such as those in bins 1.06 (for FA), 4.01 (for PCA and FA), 5.04 (for FA), 8.05 (for PCA), and 10.03 and 3.06 (for DFAT and some dimers). CONCLUSIONS: The effect of individual SNPs significantly associated with stem hydroxycinnamate content was low, explaining a low percentage of total phenotypic variability (7 to 10%). Nevertheless, we spotlighted new genomic regions associated with the accumulation of cell-wall-bound hydroxycinnamic acids in the maize stem, and genes involved in cell wall modulation in response to biotic and abiotic stresses have been proposed as candidate genes for those quantitative trait loci (QTL). In addition, we cannot rule out that uncharacterized genes linked to significant SNPs could be implicated in dimer formation and arobinoxylan feruloylation because genes involved in those processes have been poorly characterized. Overall, genomic selection considering markers distributed throughout the whole genome seems to be a more appropriate breeding strategy than marker-assisted selection focused in markers linked to QTL.

Transcriptomic changes in Cucurbita pepo fruit after cold storage: differential response between two cultivars contrasting in chilling sensitivity.

BACKGROUND: Zucchini fruit is susceptible to chilling injury (CI), but the response to low storage temperature is cultivar dependent. Previous reports about the response of zucchini fruit to chilling storage have been focused on the physiology and biochemistry of this process, with little information about the molecular mechanisms underlying it. In this work, we present a comprehensive analysis of transcriptomic changes that take place after cold storage in zucchini fruit of two commercial cultivars with contrasting response to chilling stress. RESULTS: RNA-Seq analysis was conducted in exocarp of fruit at harvest and after 14 days of storage at 4 and 20 °C. Differential expressed genes (DEGs) were obtained comparing fruit stored at 4 °C with their control at 20 °C, and then specific and common up and down-regulated DEGs of each cultivar were identified. Functional analysis of these DEGs identified similarities between the response of zucchini fruit to low temperature and other stresses, with an important number of GO terms related to biotic and abiotic stresses overrepresented in both cultivars. This study also revealed several molecular mechanisms that could be related to chilling tolerance, since they were up-regulated in cv. Natura (CI tolerant) or down-regulated in cv. Sinatra (CI sensitive). These mechanisms were mainly those related to carbohydrate and energy metabolism, transcription, signal transduction, and protein transport and degradation. Among DEGs belonging to these pathways, we selected candidate genes that could regulate or promote chilling tolerance in zucchini fruit including the transcription factors MYB76-like, ZAT10-like, DELLA protein GAIP, and AP2/ERF domain-containing protein. CONCLUSIONS: This study provides a broader understanding of the important mechanisms and processes related to coping with low temperature stress in zucchini fruit and allowed the identification of some candidate genes that may be involved in the acquisition of chilling tolerance in this crop. These genes will be the basis of future studies aimed to identify markers involved in cold tolerance and aid in zucchini breeding programs.

Bilingualism and language in children with autistic spectrum disorder: a systematic review.

INTRODUCTION: Communication and language skills are among the most severely affected domains in individuals with autistic spectrum disorder (ASD). When a child diagnosed with ASD lives in a bilingual environment, the parents often express concerns about whether their child should learn both languages simultaneously, turning to specialists for advice. Despite the lack of evidence of any negative effect, some professionals disagree on this subject. In this systematic review we study whether bilingualism affects language development in children with ASD. METHODS: We reviewed the literature published in 4 different databases. After applying a series of selection criteria, we selected 12 scientific articles, including a total of 328 children diagnosed with ASD (169 bilingual and 159 monolingual), with ages ranging from 3 to 12 years. These patients were evaluated with different receptive and expressive language assessment instruments covering several areas. The assessments were performed directly on the children, although indirect assessment of parents was also performed in some studies. CONCLUSIONS: There seems to be consensus regarding the assertion that bilingualism does not entail any additional difficulty for language development in children with ASD from the age of 3.

Peritoneal scintigraphy and SPECT/TC in the diagnosis of leaks in patients on peritoneal dialysis.

OBJECTIVE: To assess the usefulness of peritoneal cavity scintigraphy and the contribution of SPECT/CT in patients on peritoneal dialysis with suspected leak. METHODOLOGY: An observational case series study is carried out. It consists of a longitudinal, retrospective and descriptive study. 11 patients on peritoneal dialysis were studied and it was realiced a peritoneal cavity scintigraphy test and SPECT/CT to evaluate a peritoneal leak. RESULTS: In 54,5% of the patients, a positive study of peritoneal leak was obtained. The most frequent localitations were in the abdominal wall at the catheter entry level and the inguinal hernia. In the cases with sintomatology like pain and celullitis of the subcutaneous tract of the cateter the frequent of leak was 100%. There was a change in therapeutic management in patients with a positive study. There was not relevant changes in initial dialysis regimen in patients with a negative study. In this cases, except for one patient who required hemodialysis, all patients experienced clinical improvement. CONCLUSIONS: Peritoneal scintigraphy and SPECT/CT study are non-invasive techniques that allow an adequate diagnosis and subsequent management of peritoneal leak.

Bilingualism and language in children with autistic spectrum disorder: a systematic review. / Bilingüismo y lenguaje en niños con trastorno del espectro autista: una revisión sistemática.

INTRODUCTION: Communication and language skills are among the most severely affected domains in individuals with autistic spectrum disorder (ASD). When a child diagnosed with ASD lives in a bilingual environment, the parents often express concerns about whether their child should learn both languages simultaneously, turning to specialists for advice. Despite the lack of evidence of any negative effect, some professionals disagree on this subject. In this systematic review we study whether bilingualism affects language development in children with ASD. METHODS: We reviewed the literature published in 4 different databases. After applying a series of selection criteria, we selected 12 scientific articles, including a total of 328 children diagnosed with ASD (169 bilingual and 159 monolingual), with ages ranging from 3 to 12 years. These patients were evaluated with different receptive and expressive language assessment instruments covering several areas. The assessments were performed directly on the children, although indirect assessment of parents was also performed in some studies. CONCLUSIONS: There seems to be consensus regarding the assertion that bilingualism does not entail any additional difficulty for language development in children with ASD from the age of 3.

[Linguistic impairments in patients with mild cognitive impairment: a systematic review]. / Alteraciones lingüísticas en pacientes con deterioro cognitivo leve. Revisión sistemática.

INTRODUCTION: The neuropsychological profile of patients with mild cognitive impairment (MCI) has been the target of several investigations. However, few works have been published about the language profile in these patients. AIM: To analyse and integrate the published scientific literature about this topic after the systematic review carried out by Johnson and Lin in 2014. SUBJECTS AND METHODS: A systematic review was carried out in which three databases (Web of Science, PubMed and PsycInfo) were consulted. Seventeen studies have been analysed, with adult participants diagnosed with MCI, that included at least one control group, and studies that evaluated language parameters. A self-made registration protocol has been applied to encode the characteristics and results of the studies; and the quality of the studies and articles has been evaluated through a self-elaboration scale based on previously validated instruments. RESULTS: Patients with MCI can present deficits in naming, speech production, oral comprehension, and written comprehension. CONCLUSIONS: It is important to evaluate language in patients with MCI, although this exploration does not allow establishing a diagnosis on by itself. However, the pathology variability associated with the diagnosis, the age, the language, and the educational level of the participants, as well as the sample size, and the instruments and measures used to evaluate the language in the studies reviewed, make impossible to obtain a conclusive statement, so further research about this topic is needed.

TITLE: Alteraciones lingüísticas en pacientes con deterioro cognitivo leve. Revisión sistemática.Introducción. El perfil neuropsicológico de los pacientes con deterioro cognitivo leve ha sido objeto de estudio de diversas investigaciones. Sin embargo, se han publicado relativamente pocos trabajos sobre las características del lenguaje en estos pacientes. Objetivo. Analizar e integrar la bibliografía publicada sobre el tema tras la revisión sistemática realizada por Johnson y Lin en 2014. Sujetos y métodos. Se ha realizado una revisión sistemática en la que se han consultado tres bases de datos (Web of Science, PubMed y PsycInfo). Se han analizado 17 estudios empíricos revisados por pares, con participantes adultos con deterioro cognitivo leve, que incluyen al menos un grupo control y que evalúan parámetros de lenguaje. Se ha aplicado un protocolo de registro de elaboración propia para codificar las características y los resultados de los estudios, y se ha evaluado la calidad de los estudios y los artículos en los que se han publicado a través de una escala de elaboración propia basada en instrumentos validados previamente. Resultados. Los pacientes con deterioro cognitivo leve pueden presentar déficits en denominación, producción del discurso, comprensión oral y comprensión escrita. Conclusiones. Es importante evaluar el lenguaje en pacientes con deterioro cognitivo leve, aunque dicha exploración no permita establecer por sí sola un diagnóstico. No obstante, la variabilidad en la patología asociada al diagnóstico, la edad, el idioma y el nivel educativo de los participantes, así como al tamaño muestral, y los instrumentos utilizados para evaluar el lenguaje en los estudios revisados impiden que se puedan realizar afirmaciones concluyentes y hacen que sea necesario realizar más investigación sobre el tema.

Trend of in-hospital deaths by pulmonary embolism in Ecuador. Findings from 2011-2018 national reports.

BACKGROUND: Pulmonary embolism (PE) is a potentially fatal disease related to venous thromboembolism. Information regarding this pathology in the Ecuadorian population is limited. This study aims to present the PE hospital mortality rates (HMR) in Ecuador, analyze its trend and risk factors. METHODS: An epidemiological, descriptive and cross-sectional study based on the reporting and trend analysis of pulmonary embolism HMR in the Ecuadorian population from 2011 to 2018 through the governmental database of the Ecuadorian National Statistics and Census Institute, was conducted. RESULTS: In Ecuador, PE hospital discharges (HD) varied from 358 in 2011 to 424 in 2018. More than 60% of patients were older than 60 years. Also, the frequency of PE with acute cor pulmonale increased from 3.07% in 2011 to 16.98% in 2018 (P<0.05). The HMR by 100 HD increased between 2011 (12.85/100 HD) and 2018 (17.02/100 HD) (P<0.05), with the highest rate reported in 2017 (21.52/100 HD). In the period studied, 505 in-hospital deaths were reported in patients with PE, the average age in this group was 64.3 years, 58.42% were female, and 10.89% had acute cor pulmonale (ICD-10 I26.0). Risk factors associated with PE in-hospital death were acute cor pulmonale (OR 1.63, 95% CI: 1.18 to 2.25, P<0.01) and 60 years or more (OR 1.73, 95% CI 1.40-2.15, P<0.01). CONCLUSION: A significant increase in PE HMR in Ecuador was found. Also, acute cor pulmonale and age of 60 years or more may be potential risk factors for in-hospital death in patients with PE.

Association mapping for maize stover yield and saccharification efficiency using a multiparent advanced generation intercross (MAGIC) population.

Cellulosic ethanol derived from fast growing C4 grasses could become an alternative to finite fossil fuels. With the potential to generate a major source of lignocellulosic biomass, maize has gained importance as an outstanding model plant for studying the complex cell wall network and also to optimize crop breeding strategies in bioenergy grasses. A genome-wide association study (GWAS) was conducted using a subset of 408 Recombinant Inbred Lines (RILs) from a Multi-Parent Advanced Generation Intercross (MAGIC) Population in order to identify single nucleotide polymorphisms (SNPs) associated with yield and saccharification efficiency of maize stover. We identified 13 SNPs significantly associated with increased stover yield that corresponded to 13 QTL, and 2 SNPs significantly associated with improved saccharification efficiency, that could be clustered into 2 QTL. We have pointed out the most interesting SNPs to be implemented in breeding programs based on results from analyses of averaged and yearly data. Association mapping in this MAGIC population highlight genomic regions directly linked to traits that influence the final use of maize. Markers linked to these QTL could be used in genomic or marker-assisted selection programs to improve biomass quality for ethanol production. This study opens a possible optimisation path for improving the viability of second-generation biofuels.

[Psychological adaptation in children with autism spectrum disorder and its effect on family quality of life]. / Conducta adaptativa en niños con trastorno del espectro autista y su efecto sobre la calidad de vida familiar.

INTRODUCTION: In most children with autism spectrum disorder (ASD), other difficulties that do not fall within the diagnostic criteria arose, and could have an impact on family quality of life. Previous research has shown several relationships among these variables and family quality of life, however results are contradictories. AIM: To examine the role of psychological adaptation (including emotional symptoms, behavioral problems, hyperactivity, problems with peers, and prosocial behavior) in children with ASD and typical development, and its impact on family quality of life. SUBJECTS AND METHODS: Twenty-four families of children with ASD (level 1 of support) and 25 families of children with typical development between 6 and 13 years old. We have considered diagnosis of Asperger syndrome (following DSM-IV-TR) with ASD-level 1 of support (following DSM-5). We have evaluated intelligence, vocabulary, adaptive behavior, and family quality of life. RESULTS: We have found significant differences in those variables related to psychological adaptation, and in some components of the family quality of life (family interaction, physical and emotional wellbeing). In our regression model, prosocial behaviors and the group were the main predictors of satisfaction on family quality of life. CONCLUSION: It is important to pay attention to the prosocial behaviors in ASD due to its potential protective effect.

TITLE: Conducta adaptativa en niños con trastorno del espectro autista y su efecto sobre la calidad de vida familiar.Introducción. En la mayoría de los niños con trastorno del espectro autista (TEA) aparecen dificultades asociadas que, aunque no se incluyen en los criterios diagnósticos, podrían tener impacto sobre la calidad de vida familiar. La bibliografía ha mostrado algunas relaciones entre estas variables y la calidad de vida familiar, aunque los resultados no son concluyentes. Objetivo. Examinar el papel de la conducta adaptativa (incluyendo síntomas emocionales, problemas de conducta, hiperactividad/falta de atención, problemas de relaciones entre compañeros y comportamiento prosocial) en niños con TEA y con desarrollo típico, y su posible impacto sobre la calidad de vida familiar. Sujetos y métodos. Veinticuatro familias de niños con TEA (nivel 1 de apoyo) y 25 familias de niños con desarrollo típico con edades comprendidas entre 6 y 13 años. Se ha igualado el síndrome de Asperger (según el DSM-IV-TR) con el TEA con nivel 1 de apoyo (según el DSM-5). Se han evaluado la inteligencia, el vocabulario, la conducta adaptativa y la calidad de vida familiar. Resultados. Se han encontrado diferencias significativas en las variables relacionadas con la conducta adaptativa y en algunos de los componentes de la calidad de vida familiar (interacción familiar, bienestar físico y emocional). En el modelo de regresión, presentar unos mejores niveles de conducta prosocial y el grupo aparecieron como los principales predictores de la satisfacción percibida en la calidad de vida familiar. Conclusión. Es importante atender a las dificultades en la conducta prosocial en el TEA, dado su potencial efecto protector sobre la calidad de vida familiar.

Consistency and identifiability of football teams: a network science perspective.

We investigated the ability of football teams to develop a particular playing style by looking at their passing patterns. Using the information contained in the pass sequences during matches, we constructed the pitch passing networks of teams, whose nodes are the divisions of the pitch for a given spatial scale and links account for the number of passes from region to region. We translated football passings networks into their corresponding adjacency matrices. We calculated the correlations between matrices of the same team to quantify how consistent the passing patterns of a given team are. Next, we quantified the differences with other teams' matrices and obtained an identifiability parameter that indicates how unique are the passing patterns of a given team. Consistency and identifiability rankings were calculated during a whole season, allowing to detect those teams of a league whose passing patterns are different from the rest. Furthermore, we found differences between teams playing at home or away. Finally, we used the identifiability parameter to investigate what teams imposed their passing patterns over the rivals during a given match.

Study of the coumarate decarboxylase and vinylphenol reductase activities of Dekkera bruxellensis (anamorph Brettanomyces bruxellensis) isolates.

AIM: To evaluate the coumarate descarboxylase (CD) and vinylphenol reductase (VR) activities in Dekkera bruxellensis isolates and study their relationship to the growth rate, protein profile and random amplified polymorphic DNA (RAPD) molecular pattern. METHODS AND RESULTS: CD and VR activities were quantified, as well, the growth rate, intracellular protein profile and molecular analysis (RAPD) were determined in 12 isolates of D. bruxellensis. All the isolates studied showed CD activity, but only some showed VR activity. Those isolates with the greatest growth rate did not present a different protein profile from the others. The FASC showed a relationship between RAPD molecular patterns and VR activity. CONCLUSION: CD activity is common to all of the D. bruxellensis isolates. This was not the case with VR activity, which was detected at a low percentage in the analysed micro-organisms. A correlation was observed between VR activity and the RAPD patterns. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study that quantifies the CD and VR enzyme activities in D. bruxellensis, demonstrating that these activities are not present in all isolates of this yeast.

EXPERIMENTAL EVALUATION OF NEUTRON SHIELDING MATERIALS.

A new proposed design of neutron shielding material-based on the commercial material Borotron UH050 with an addition of Al(OH)3-is evaluated in order to determine if its neutron and gamma shielding properties match those of a reference material, NS4FR. Neutron and gamma dosimetry measurements are performed, as well as neutron spectrometry measurements and Monte Carlo simulations. Negligible differences are found between the materials for neutron shielding, while significant differences are found for gamma shielding. The effect of Al(OH)3 addition to Borotron UH050 is to reduce neutron shielding properties while increasing gamma shielding properties. The resulting material is as efficient as NS4FR for neutron shielding but less efficient for gamma shielding-thicknesses 20% higher are required to match gamma shielding properties of NS4FR. Monte Carlo models of the materials are validated based on the performed measurements of neutron spectra and neutron and gamma ambient dose equivalent.

[Lumbar neuroendocrine carcinoma with invasion of the neural canal]. / Carcinoma neuroendocrino lumbar con invasion al canal neural.

INTRODUCTION: Extraspinal tumors are a rare cause of lumbar root compression and neuroendocrine origin are one of the least frequent of this group. CASE REPORT: A 70 years-old woman complained of pain in low back and her right leg. Following image studies a tumor at the level of the L2 vertebrae was diagnosed. This was operated on and a neuroendocrine carcinoma was removed. CONCLUSION: The neuroendocrine tumors show a slow grows typically and are located in the gastrointestinal tract and lung. These are very rare in others localizations.

[Communicative and social-adaptive profile in children with autism spectrum disorder: a new approach based on the DSM-5 criteria]. / Perfil comunicativo y de adaptacion social en poblacion infantil con trastornos del espectro autista: nuevo enfoque a partir de los criterios del DSM-5.

INTRODUCTION: Following the adoption of the new international diagnosis classification from the Diagnostic and Statistical Manual (DSM-5), autism spectrum disorder (ASD) has been established as a dimensional category that includes other disorders that were previously considered as separate entities. Previous research has shown that some people with this disorder exhibit different communicative and linguistic profiles. Therefore, contradictory results could be found among people who receive the same diagnosis. AIM: To distinguish structural language aspects (expression and comprehension), interactive aspects (pragmatics), and social adaptation between children with an ASD-level 1 of support and children with typical development. SUBJECTS AND METHODS: Seventeen children with Asperger syndrome (according to the DSM-IV-TR), and 20 children with typical development between 7 and 12 years old. We have equated diagnosis of Asperger syndrome with ASD-level 1 of support. We have evaluated intelligence quotient, communication, and social adaptation with direct and indirect standardized parental scales. RESULTS: We have found significant differences in comprehension (p = 0.025), interaction (p = 0.001), and social adaptation (p = 0.001) between the two groups. CONCLUSIONS: Subjects with ASD-level 1 of support demonstrate an average intelligence quotient, and good expressive structure (syntax and semantic level), which may be different from other children who receive the same diagnosis, due to the wide heterogeneity of the disorder. Nevertheless, our subjects have problems related to comprehension of grammar structure, pragmatics, and social adaptation. These difficulties could be related to emotional and social problems.

TITLE: Perfil comunicativo y de adaptacion social en poblacion infantil con trastornos del espectro autista: nuevo enfoque a partir de los criterios del DSM-5.Introduccion. Tras la nueva clasificacion diagnostica del Manual diagnostico y estadistico de los trastornos mentales, quinta edicion (DSM-5), el trastorno del espectro autista (TEA) ha pasado a considerarse una categoria dimensional que engloba una serie de trastornos que antes se consideraban como entidades diferentes. La bibliografia previa ha mostrado perfiles comunicativos y linguisticos diferentes en personas con estos trastornos, por lo que podrian encontrarse resultados contradictorios en los individuos que en la actualidad reciben un diagnostico de TEA. Objetivo. Identificar los aspectos del lenguaje estructural (expresion y comprension), interaccion (pragmatica) y adaptacion social diferenciales en niños con diagnostico de TEA de nivel 1 de apoyo y compararlos con niños con desarrollo tipico. Sujetos y metodos. Diecisiete niños con sindrome de Asperger (segun el DSM-IV-TR) y 20 niños con desarrollo tipico de entre 7 y 12 años. Se ha equiparado el sindrome de Asperger del DSM-IV-TR con el TEA con nivel 1 de apoyo del DSM-5. Se ha evaluado la inteligencia, la comunicacion y la adaptacion social con medidas directas estandarizadas y medidas indirectas paternas. Resultados. Se han encontrado diferencias significativas en comprension (comprension de estructuras gramaticales; p = 0,025), interaccion (cuestionario de capacidades y dificultades total; p = 0,001) y adaptacion social (Children's Communication Checklist-2 total; p = 0,001) entre los grupos. Conclusiones. Los participantes con TEA con nivel 1 muestran un nivel de inteligencia normal y buena expresividad estructural (sintaxis y semantica), lo que podria diferenciarlos sustancialmente, dada la gran heterogeneidad del trastorno, de otros niños que en la actualidad tambien reciben el diagnostico de TEA. No obstante, nuestros participantes tambien presentan problemas de comprension de estructuras gramaticales, interaccion pragmatica y adaptacion social. Estas dificultades podrian relacionarse con posibles problemas emocionales y de socializacion.

Interaction of alkylputrescines with ornithine decarboxylase from rat liver and Escherichia coli: an in vitro and in vivo study.

The inhibitory effect of a series of 2-alkylputrescines on rat liver and Escherichia coli ornithine decarboxylase (L-ornithine carboxy-lyase, EC 4.1.1.17) was examined. At 2.5 mM concentrations, 2-methyl-, 2-propyl-, 2-butyl-, 2-pentyl- and 2-hexylputrescines were stronger inhibitors of the mammalian enzyme than putrescine. Only the higher homologues (from 2-propyl- to 2-hexylputrescine) were inhibitors of the E. coli enzyme. An analysis of the effect of increasing concentrations of the 2-alkylputrescines showed that the main difference in the behaviour of the mammalian and E. coli decarboxylases toward 2-alkylputrescines was that the former was strongly inhibited by 2-methylputrescine whereas the latter was not. 2-Alkylputrescines were found to be competitive inhibitors of both the bacterial and mammalian enzyme. The smallest Ki values (0.1 and 0.5 mM) were found for the 2-hexyl- and 2-pentylputresciens. N-Methyl-, N-ethyl-, N-propyl- and N-butylputrescines (50 mumol per 100 g body weight) were assayed as inhibitors of thioacetamide-induced rat liver ornithine decarboxylase. N-Propylputrescine was found to be the most inhibitory (66% inhibition) and although the N-alkylputrescines were taken up by the liver, they did not inhibit the liver polyamine pools. Both putrescine and N-methylputrescine were found to stabilize the thioacetamide-induced ornithine decarboxylase at the onset of the enzyme's degradation, while 2-alkylputrescines were inhibitory under similar conditions. N-Methylputrescine induced antizyme in thioacetamide-treated rats. In thioacetamide- or dexamethasone-treated rats, 2-methylputrescine was found to be the strongest in vivo inhibitor of the liver decarboxylase. Although 2-alkylputrescines were efficiently taken up by the liver, they did not noticeably inhibit its polyamine pools. 2-methylputrescine decreased the putrescine concentration of the liver, but not its spermidine and spermine content. No induction of ornithine decarboxylase antizyme by 2-methylputrescine could be detected. The intrahepatic concentration of the latter decreased with time, very likely due to its degradation by a diamine oxidase, since the decrease was inhibited by aminoguanidine.

Effect of N-alkyl and C-alkylputrescines on the activity of ornithine decarboxylase from rat liver and E. coli.

N-Methyl-, N-ethyl-, N-propyl-, N-butyl-, N,N-dimethyl- and N,N'-dimethylputrescines were assayed as inhibitors of ornithine decarboxylase (EC 4.1.1.17) from rat liver and from Escherichia coli. They were found to be poor inhibitors, with the exception of N-propylputrescine and N,N-dimethylputrescine, which were inhibitory at 25 mM. A homologous series of 1-alkylputrescines ranging from 1-methylputrescine (1,4-diaminopentane) to 1-heptylputrescine (1,4-diaminoundecane) was assayed for effect on the activity of ornithine decarboxylase from the same sources. 1-Methylputrescine (5 mM) inhibited the mammalian enzyme, while the higher homologues showed significantly less inhibitory activity. When assayed on the bacterial enzyme, 1-methylputrescine (5 mM) was not inhibitory, while the higher homologues showed inhibitory effects. At higher concentrations, 1-methylputrescine and 1-heptylputrescine were the best inhibitors of these series of rat liver ornithine decarboxylase. When 1-methylputrescine, 2-methylputrescine, 1,2-dimethylputrescine, 1,3-dimethylputrescine and 1,4-dimethylputrescine were assayed as inhibitors of the decarboxylase, 2-methylputrescine was found to be the best inhibitor of the rat liver enzyme, while 1,3-dimethylputrescine was the best inhibitor of the bacterial enzyme. 1,4-Dimethylputrescine (2,5-diaminohexane) did not inhibit the enzyme from either source. Both, 2-methylputrescine and 1-methylputrescine, as well as the 1,2- and 1,3-dimethylputrescines were competitive inhibitors of the enzyme, and a Ki of 1 mM was obtained for 2-methylputrescine when the rat liver decarboxylase was used. N-Methyl, 1-methyl and 2-methylputrescines were found to inhibit in vivo the activity of rat liver ornithine decarboxylase which had been previously induced by thioacetamide treatment. 2-Methylputrescine (50 mumol/100 g body weight) was found to be the best in vivo inhibitor (93% inhibition), while putrescine under similar conditions inhibited 56% of the enzymatic activity.

Putrescine distribution in Escherichia coli studied in vivo by 13C nuclear magnetic resonance.

In order to study the intracellular polyamine distribution in Escherichia coli, 13C-NMR spectra of [1,4-13C]putrescine were obtained after addition of the latter to intact bacteria. The 13C-enriched methylene signal underwent line broadening. When the cells were centrifuged after 90 min the cell-bound putrescine peak had a linewidth of 23 Hz, while the supernatant liquid showed an unbound putrescine signal with a linewidth smaller than 1 Hz. By using 13C-enriched internal standards it could be shown that the linewidening was not due to the heterogeneity of the medium or to an in vivo paramagnetic effect. Cell-bound putrescine was liberated by addition of trichloroacetic acid and was therefore non-covalently linked to macromolecular cell structures. Cell-bound [13C]putrescine could be displaced by addition of an excess of [12C]putrescine. When samples of membranes, soluble protein, DNA, tRNA and ribosomes from E. coli were incubated with [1,4-13C]putrescine, strong binding was detected only in the ribosomal and membrane fractions. The ribosome-putrescine complex showed properties similar to those determined with the intact cells. By measuring the nuclear Overhauser enhancements eta, it was possible to estimate that only about 50% of the polyamine was linked to the macromolecules. Determination of the T1 values of free and ribosomal-bound putrescine allowed the calculation of a correlation time, tau c = 4 X 10(-7) s for the latter. T1 and tau c values found for the ribosome-putrescine complex were those expected for a motional regime of slowly tumbling molecules.

Insulin resistance and hypertension in postmenopausal women.

The aim of the study was to elucidate the role of hyperinsulinaemia/insulin resistance in hypertension of lean postmenopausal women. Twenty-four women with essential hypertension (systolic/diastolic > or =140/90 mm Hg) and a body mass index (BMI) less than 26 kg/m(2) not receiving antihypertensive treatment or who had been without treatment for a 4-week washout period, and 10 normotensive postmenopausal weight- and aged-matched controls were compared. Both groups were not receiving hormone replacement therapy. Hip and waist circumferences were measured and waist/hip ratios were calculated. Casual blood pressure was measured in triplicate. Neither the fasting plasma glucose nor serum insulin levels in hypertensive women and normotensives differed significantly. During 2 h oral glucose (75 g)-tolerance test the mean plasma glucose levels after 30 min (172.5 +/- 40.24 mg/dl vs. 143.67 +/- 20.16 mg/dl), 60 min (134.88 +/- 38.78 mg/dl vs. 112.33 +/- 5.44 mg/dl) and 120 min (116.08 +/- 26.65 mg/dl vs. 95.56 +/- 20.17 mg/dl) were significantly higher in hypertensives than that for normotensives (P < 0.05 for all three comparisons). The mean serum insulin levels of hypertensive women were significantly higher than that in normotensives after 15 min (92.04 +/- 59.90 microU/ml vs. 54.89 +/- 33.67 microU/ml) and 120 min (49.63 +/- 44.45 microU/ml vs. 19.22 +/- 24.10 microU/ml; P< 0.05 for both comparisons). The mean serum insulin: plasma glucose ratio for hypertensive women was significantly higher than that for normotensives after 15 min (0.596 +/- 0.46 vs. 0.359 +/- 0.20 microU/mg), 60 min (0.406 +/- 0.30 vs. 0.329 +/- 0.25 microU/mg) and 120 min (0.436 +/- 0.35 vs. 0.205 +/- 0.26 microU/mg) (P < 0.05 for all three comparisons). Significant correlations were observed between the daytime period and 24-h average ambulatory systolic blood pressure and the area under the serum insulin curve (r = 0.41 and 0.36, respectively). For non-dippers we found higher fasting insulinaemias but the AUC(insulin) did not differ. Plasma glucose levels did not differ either during fasting or during OGTT (AUC(glucose)). Insulinogenic index was higher in dippers than in non-dippers. We conclude that in lean, postmenopausal hypertensive women insulin resistance is increased compared with age- and weight-matched normotensive women. Also, hyperinsulinaemia correlates with ambulatory systolic blood pressure. Thus, insulin resistance may possibly be involved as a pathogenetic factor in lean, postmenopausal hypertensive women.

Altered circadian blood pressure profile in patients with active acromegaly. Relationship with left ventricular mass and hormonal values.

To determine the relationships between the circadian blood pressure profile and left ventricular mass, hormonal pattern and insulin sensitivity indices in patients with active acromegaly, ambulatory 24-h blood pressure monitoring (ABPM) was recorded in 25 subjects (47.0 +/- 15.1 years, range 23-72). Serum growth hormone (GH) and insulin-like growth factor-1, fasting and mean plasma glucose and insulin during oral glucose tolerance test (OGTT), insulinogenic index, the sum of the plasma insulin levels and the homeostasis model insulin resistance index (Homa's index) were determined. Left ventricular mass index (LVMI) was calculated from two-dimensional guided M-mode echocardiogram. The prevalence of hypertension was 56% (n = 14) and 40% (n = 10) according to sphygmomanometric measurements and ABPM, respectively. Non-dipping profile was observed in six of 10 hypertensives and in six of 15 normotensives. Serum growth hormone, fasting glucose, the area under the serum insulin curve and LVMI were higher for acromegalics with non-dipping profile than for dippers (all of them, P < 0.05). In non-dippers daytime heart rate was higher than night time (P < 0.001). In conclusion, the main observations in the present study suggested that both normotensive and hypertensive acromegalics had a highly prevalent non-dipping profile with a preserved circadian pattern of heart rate, that was associated with higher levels of serum GH. The disturbance in nocturnal blood fall in normotensives was associated with a decreased insulin sensitivity. The role of GH in blood pressure circadian rhythm regulation in essential hypertension deserves further studies.