Growth regulators and their reflection on different hop genotypes cultivated under in vitro conditions / Reguladores de crescimento e seu reflexo em diferentes genótipos de lúpulo cultivados in vitro

Hops is a new culture in Brazil. Tissue culture can be an important technique for rapid hop propagation. This paper aims to characterize responses from different genotypes under different growth regulators through the interrelationship of response variables important to hop in vitro growth. Three genotypes were cultivated in six culture media with different combinations of growth regulators, BAP (6-benzylaminopurine), IAA (3-indolacetic acid) and GA3 (gibberellic acid). The means were compared by orthogonal contrasts and the interrelationship of the response variables was performed by path analysis. American genotypes showed favorable root development under the BAP + IAA combination, while the use of IAA improved shoot development. The origin of genotypes was important for defining the best protocol for in vitro cultivation. The path coefficient showed that the variable number of shoots has stronger direct effect on the number of nodal segments. Additionally, in tissue culture assays, the use of a covariable and proper error distribution significantly increased experimental accuracy.

O lúpulo é uma nova cultura no Brasil. A cultura de tecidos pode ser uma técnica importante para a propagação rápida do lúpulo. Este artigo tem como objetivo caracterizar respostas de diferentes genótipos sob diferentes reguladores de crescimento através da inter-relação de variáveis de resposta importantes para o crescimento in vitro. Três genótipos foram cultivados em seis meios de cultura com diferentes combinações de reguladores de crescimento, BAP (6-benzilaminopurina), AIA (ácido 3-indolacético) e GA3 (ácido giberélico). As médias foram comparadas por contrastes ortogonais e a inter-relação das variáveis de resposta foi realizada por análise de trilha. Os genótipos americanos apresentaram desenvolvimento radicular favorável sob a combinação BAP + AIA, enquanto o uso do AIA melhorou o desenvolvimento da parte aérea. A origem dos genótipos foi importante para definir o melhor protocolo para o cultivo in vitro. O coeficiente de trilha mostrou que a variável número de brotos tem um efeito direto mais forte no número de segmentos nodais. Adicionalmente, em experimentos com cultura de tecidos, o uso de uma covariável e distribuição de erro adequada aumentou significativamente a precisão experimental.

Growth regulators and their reflection on different hop genotypes cultivated under in vitro conditions / Reguladores de crescimento e seu reflexo em diferentes genótipos de lúpulo cultivados in vitro

Hops is a new culture in Brazil. Tissue culture can be an important technique for rapid hop propagation. This paper aims to characterize responses from different genotypes under different growth regulators through the interrelationship of response variables important to hop in vitro growth. Three genotypes were cultivated in six culture media with different combinations of growth regulators, BAP (6-benzylaminopurine), IAA (3-indolacetic acid) and GA3 (gibberellic acid). The means were compared by orthogonal contrasts and the interrelationship of the response variables was performed by path analysis. American genotypes showed favorable root development under the BAP + IAA combination, while the use of IAA improved shoot development. The origin of genotypes was important for defining the best protocol for in vitro cultivation. The path coefficient showed that the variable number of shoots has stronger direct effect on the number of nodal segments. Additionally, in tissue culture assays, the use of a covariable and proper error distribution significantly increased experimental accuracy.

O lúpulo é uma nova cultura no Brasil. A cultura de tecidos pode ser uma técnica importante para a propagação rápida do lúpulo. Este artigo tem como objetivo caracterizar respostas de diferentes genótipos sob diferentes reguladores de crescimento através da inter-relação de variáveis de resposta importantes para o crescimento in vitro. Três genótipos foram cultivados em seis meios de cultura com diferentes combinações de reguladores de crescimento, BAP (6-benzilaminopurina), AIA (ácido 3-indolacético) e GA3 (ácido giberélico). As médias foram comparadas por contrastes ortogonais e a inter-relação das variáveis de resposta foi realizada por análise de trilha. Os genótipos americanos apresentaram desenvolvimento radicular favorável sob a combinação BAP + AIA, enquanto o uso do AIA melhorou o desenvolvimento da parte aérea. A origem dos genótipos foi importante para definir o melhor protocolo para o cultivo in vitro. O coeficiente de trilha mostrou que a variável número de brotos tem um efeito direto mais forte no número de segmentos nodais. Adicionalmente, em experimentos com cultura de tecidos, o uso de uma covariável e distribuição de erro adequada aumentou significativamente a precisão experimental.

Growth regulators and their reflection on different hop genotypes cultivated under in vitro conditions

Abstract Hops is a new culture in Brazil. Tissue culture can be an important technique for rapid hop propagation. This paper aims to characterize responses from different genotypes under different growth regulators through the interrelationship of response variables important to hop in vitro growth. Three genotypes were cultivated in six culture media with different combinations of growth regulators, BAP (6-benzylaminopurine), IAA (3-indolacetic acid) and GA3 (gibberellic acid). The means were compared by orthogonal contrasts and the interrelationship of the response variables was performed by path analysis. American genotypes showed favorable root development under the BAP + IAA combination, while the use of IAA improved shoot development. The origin of genotypes was important for defining the best protocol for in vitro cultivation. The path coefficient showed that the variable number of shoots has stronger direct effect on the number of nodal segments. Additionally, in tissue culture assays, the use of a covariable and proper error distribution significantly increased experimental accuracy.

Resumo O lúpulo é uma nova cultura no Brasil. A cultura de tecidos pode ser uma técnica importante para a propagação rápida do lúpulo. Este artigo tem como objetivo caracterizar respostas de diferentes genótipos sob diferentes reguladores de crescimento através da inter-relação de variáveis de resposta importantes para o crescimento in vitro. Três genótipos foram cultivados em seis meios de cultura com diferentes combinações de reguladores de crescimento, BAP (6-benzilaminopurina), AIA (ácido 3-indolacético) e GA3 (ácido giberélico). As médias foram comparadas por contrastes ortogonais e a inter-relação das variáveis de resposta foi realizada por análise de trilha. Os genótipos americanos apresentaram desenvolvimento radicular favorável sob a combinação BAP + AIA, enquanto o uso do AIA melhorou o desenvolvimento da parte aérea. A origem dos genótipos foi importante para definir o melhor protocolo para o cultivo in vitro. O coeficiente de trilha mostrou que a variável número de brotos tem um efeito direto mais forte no número de segmentos nodais. Adicionalmente, em experimentos com cultura de tecidos, o uso de uma covariável e distribuição de erro adequada aumentou significativamente a precisão experimental.

Growth regulators and their reflection on different hop genotypes cultivated under in vitro conditions.

Hops is a new culture in Brazil. Tissue culture can be an important technique for rapid hop propagation. This paper aims to characterize responses from different genotypes under different growth regulators through the interrelationship of response variables important to hop in vitro growth. Three genotypes were cultivated in six culture media with different combinations of growth regulators, BAP (6-benzylaminopurine), IAA (3-indolacetic acid) and GA3 (gibberellic acid). The means were compared by orthogonal contrasts and the interrelationship of the response variables was performed by path analysis. American genotypes showed favorable root development under the BAP + IAA combination, while the use of IAA improved shoot development. The origin of genotypes was important for defining the best protocol for in vitro cultivation. The path coefficient showed that the variable number of shoots has stronger direct effect on the number of nodal segments. Additionally, in tissue culture assays, the use of a covariable and proper error distribution significantly increased experimental accuracy.

Prevalence of Frailty in Brazilian Older Adults: A Systematic Review and Meta-analysis.

OBJECTIVES: Frailty is characterized by a functioning decline in multiple systems accompanied by an increase in individual's vulnerability to stressors. It appears to be higher in low and middle-income countries compared with high-income ones. This study aimed to evaluate the prevalence of frailty in non-institutionalized Brazilian older adults. DESIGN: a systematic review and meta-analysis study. SETTING: Cross-sectional and prospective data from Brazil. PARTICIPANTS: non-institutionalized adults aged 60 and older. METHODS: Electronic searches were performed in PubMed/MEDLINE, LILACS, SCOPUS and Web of Science, considering the studies published between March 2001 and July 2018, using a combination of the following terms and correlates: "elder" AND "frail" AND "prevalence" AND "Brazil". Two independent reviewers selected studies according to the inclusion criteria. Disagreements were resolved by a third reviewer (title/abstract) and by consensus. Studies with samples ≥221 subjects were considered for meta-analysis. RESULTS: 28 studies were included, while 18 had the data meta-analyzed. The majority of studies (61%) included older adults only from the Southeastern region. The number of subjects ranged from 53 to 5,532 individuals (N = 17,604) and the average age ranged from 65.6 to 85.5 years. The overall prevalence of frailty was 24%. When considering the different assessment methods, the prevalence was lower for frailty phenotype (16%) compared with other criteria (40%). Regarding sex, the prevalence of frailty was similar for women (28%) and men (25%). The prevalence of frailty was higher in older adults recruited from health care services (30%) compared to community ones (22%). CONCLUSION: In Brazil, the overall prevalence of frailty in non-institutionalized older adults is higher than observed from more developed countries. However, it may vary according to the assessment methods and settings.

Revisiting the human seminiferous epithelium cycle.

STUDY QUESTION: Can all types of testicular germ cells be accurately identified by microscopy techniques and unambiguously distributed in stages of the human seminiferous epithelium cycle (SEC)? SUMMARY ANSWER: By using a high-resolution light microscopy (HRLM) method, which enables an improved visualization of germ cell morphological features, we identified all testicular germ cells in the seminiferous epithelium and precisely grouped them in six well-delimitated SEC stages, thus providing a reliable reference source for staging in man. WHAT IS ALREADY KNOWN: Morphological characterization of germ cells in human has been done decades ago with the use of conventional histological methods (formaldehyde-based fixative -Zenker-formal- and paraffin embedding). These early studies proposed a classification of the SEC in six stages. However, the use of stages as baseline for morphofunctional evaluations of testicular parenchyma has been difficult because of incomplete morphological identification of germ cells and their random distribution in the human SEC. STUDY DESIGN, SIZE, DURATION: Testicular tissue from adult and elderly donors with normal spermatogenesis according to Levin's, Johnsen's and Bergmann's scores were used to evaluate germ cell morphology and validate their distribution and frequency in stages throughout human spermatogenesis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Testicular tissue from patients diagnosed with congenital bilateral agenesis of vas deferens (n = 3 adults) or prostate cancer (n = 3 elderly) were fixed in glutaraldehyde and embedded in araldite epoxy resin. Morphological analyses were performed by both light and transmission electron microscopy. MAIN RESULTS AND THE ROLE OF CHANCE: HRLM method enabled a reliable morphological identification of all germ cells (spermatogonia, spermatocytes and spermatids) based on high-resolution aspects of euchromatin, heterochromatin and nucleolus. Moreover, acrosomal development of spermatids was clearly revealed. Altogether, our data redefined the limits of each stage leading to a more reliable determination of the SEC in man. LIMITATIONS, REASONS FOR CAUTION: Occasionally, germ cells can be absent in some tubular sections. In this situation, it has to be taken into account the germ cell association proposed in the present study to classify the stages. WIDER IMPLICATIONS OF THE FINDINGS: Our findings bring a new focus on the morphology and development of germ cells during the SEC in human. Application of HRLM may be a valuable tool for research studies and clinical andrology helping to understand some testicular diseases and infertility conditions which remain unsolved. STUDY FUNDING/COMPETING INTEREST: Experiments were partially supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Fundação de Amparo à Pesquisa de Minas Gerais (FAPEMIG) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). The authors declare that there are no conflicts of interest. TRIAL REGISTRATION NUMBER: Not applicable.

Eosinophil-derived cytokines in health and disease: unraveling novel mechanisms of selective secretion.

Over the past two decades, our understanding of eosinophils has evolved from that of categorically destructive effector cells to include active participation in immune modulation, tissue repair processes, and normal organ development, in both health and disease. At the core of their newly appreciated functions is the capacity of eosinophils to synthesize, store within intracellular granules, and very rapidly secrete a highly diverse repertoire of cytokines. Mechanisms governing the selective secretion of preformed cytokines from eosinophils are attractive therapeutic targets and may well be more broadly applicable to other immune cells. Here, we discuss recent advances in deciphering pathways of cytokine secretion, both from intact eosinophils and from tissue-deposited cell-free eosinophil granules, extruded from eosinophils undergoing a lytic cell death.

The effect of eccentric strength training on heart rate and on its variability during isometric exercise in healthy older men.

The purpose of this study was to investigate if chronic eccentric strength training (ST) affects heart rate (HR) and heart rate variability (HRV) during sub-maximal isometric voluntary contractions (SIVC). The training group (TG) (9 men, 62 +/- 2) was submitted to ST (12 weeks, 2 days/week, 2-4 sets of 8-12 repetitions at 75-80% peak torque (PT). The control group (CG) (8 men, 64 +/- 4) did not perform ST. The HR and the HRV (RMSSD index) were evaluated during SIVC of the knee extension (15, 30 and 40% of PT). ST increased the eccentric torque only in TG, but did not change the isometric PT and the duration of SIVC. During SIVC, the HR response pattern and the RMSSD index were similar for both groups in pre- and post-training evaluations. Although ST increased the eccentric torque in the TG, it did not generate changes in HR or HRV.

High eccentric strength training reduces heart rate variability in healthy older men.

BACKGROUND: Evaluation of non-pharmacological therapies that improve autonomic control of the heart rate in older subjects has a clinical significance, because reduced heart rate variability (HRV) can be associated with higher cardiovascular morbidity and mortality rates. OBJECTIVE: To investigate if strength training improves cardiac autonomic control in healthy older men. METHODS: The HRV of nine older healthy men (mean age 62 (2.0) years) was evaluated before and after 12 weeks of isokinetic eccentric strength training (2 days/week, 2-4 sets of 8-12 repetitions at 75-80% peak torque, involving knee flexion and extension. Electrocardiogram was continuously recorded for 15 min at rest, in supine and seated positions, before and after the strength training period. To estimate strength gains, the eccentric peak torque of the dominant leg was measured at 60 degrees /s by the same isokinetic dynamometer. RESULTS: Mean systolic blood pressure decreased (123.78 (8.3) to 117.67 (10.2) mmHg, p<0.05) and peak torque increased (extension 210.02 (38.5) to 252.71 (60.9) N.m; flexion: 117.56 (25.1) to 132.96 (27.3) N.m, p<0.05) after the strength training. The frequency domain indices showed a significant training effect (p<0.05), since low frequency in normalised units and low frequency/high frequency ratio increased (supine, 57 (14) to 68 (14), 1.56 (0.85) to 2.35 (1.48); seated, 65 (15) to 74 (8.0), 2.48 (1.09) to 3.19 (1.31), respectively), and high frequency in normalised units decreased (supine, 43 (14) to 32 (14); seated, 35 (15) to 26 (8)) after the training period. CONCLUSION: The results of the present investigation suggest that high eccentric strength training performed by healthy older men increases peak torque and reduces systolic blood pressure. However, an autonomic imbalance towards sympathetic modulation predominance was induced by an unknown mechanism.

On the characterization of energy networks of proteins.

The construction of a realistic theoretical model of proteins is determinant for improving the computational simulations of their structural and functional aspects. Modeling proteins as a network of non-covalent connections between the atoms of amino acid residues has shown valuable insights into these macromolecules. The energy-related properties of protein structures are known to be very important in molecular dynamics. However, these same properties have been neglected when the protein structures are modeled as networks of atoms and amino acid residues. A new approach for the construction of protein models based on a network of atoms is presented. This method, based on interatomic interaction, takes into account the energy and geometric aspects of the protein structures that were not employed before, such as atomic occlusion inside the protein, the use of solvation, protein modeling and analysis, and the use of energy potentials to estimate the energies of interatomic non-covalent contacts. As a result, we achieved a more realistic network model of proteins. This model has the virtue of being more robust in face of different unknown variables that usually are arbitrarily estimated. We were able to determine the most connected residues of all the proteins studied, so that we are now in a better condition to study their structural role.

Finding protein-protein interaction patterns by contact map matching.

We propose a novel method for defining patterns of contacts present in protein-protein complexes. A new use of the traditional contact maps (more frequently used for representation of the intra-chain contacts) is presented for analysis of inter-chain contacts. Using an algorithm based on image processing techniques, we can compare protein-protein interaction maps and also obtain a dissimilarity score between them. The same algorithm used to compare the maps can align the contacts of all the complexes and be helpful in the determination of a pattern of conserved interactions at the interfaces. We present an example for the application of this method by analyzing the pattern of interaction of bovine pancreatic trypsin inhibitors and trypsins, chymotrypsins, a thrombin, a matriptase, and a kallikrein - all classified as serine proteases. We found 20 contacts conserved in trypsins and chymotrypsins and 3 specific ones are present in all the serine protease complexes studied. The method was able to identify important contacts for the protein family studied and the results are in agreement with the literature.

Finding protein-protein interaction patterns by contact map matching

We propose a novel method for defining patterns of contacts present in protein-protein complexes. A new use of the traditional contact maps (more frequently used for representation of the intra-chain contacts) is presented for analysis of inter-chain contacts. Using an algorithm based on image processing techniques, we can compare protein-protein interaction maps and also obtain a dissimilarity score between them. The same algorithm used to compare the maps can align the contacts of all the complexes and be helpful in the determination of a pattern of conserved interactions at the interfaces. We present an example for the application of this method by analyzing the pattern of interaction of bovine pancreatic trypsin inhibitors and trypsins, chymotrypsins, a thrombin, a matriptase, and a kallikrein - all classified as serine proteases. We found 20 contacts conserved in trypsins and chymotrypsins and 3 specific ones are present in all the serine protease complexes studied. The method was able to identify important contacts for the protein family studied and the results are in agreement with the literature.

On the characterization of energy networks of proteins

The construction of a realistic theoretical model of proteins is determinant for improving the computational simulations of their structural and functional aspects. Modeling proteins as a network of non-covalent connections between the atoms of amino acid residues has shown valuable insights into these macromolecules. The energy-related properties of protein structures are known to be very important in molecular dynamics. However, these same properties have been neglected when the protein structures are modeled as networks of atoms and amino acid residues. A new approach for the construction of protein models based on a network of atoms is presented. This method, based on interatomic interaction, takes into account the energy and geometric aspects of the protein structures that were not employed before, such as atomic occlusion inside the protein, the use of solvation, protein modeling and analysis, and the use of energy potentials to estimate the energies of interatomic non-covalent contacts. As a result, we achieved a more realistic network model of proteins. This model has the virtue of being more robust in face of different unknown variables that usually are arbitrarily estimated. We were able to determine the most connected residues of all the proteins studied, so that we are now in a better condition to study their structural role.

The Star STING server: a multiplatform environment for protein structure analysis.

Star STING is the latest version of the STING suite of programs and corresponding database. We report on five important aspects of this package that have acquired some new characteristics, designed to add key advantages to the whole suite: 1) availability for most popular platforms and browsers, 2) introduction of the STING_DB quality assessment, 3) improvement in algorithms for calculation of three STING parameters, 4) introduction of five new STING modules, and 5) expansion of the existing modules. Star STING is freely accessible at: http://sms.cbi.cnptia.embrapa.br/SMS/, http://trantor.bioc.columbia.edu/SMS, http://www.es.embnet.org/SMS/, http://gibk26.bse.kyutech.ac.jp/SMS/ and http://www.ar.embnet.org/SMS.

Lipid bodies: Structural markers of inflammatory macrophages in innate immunity.

OBJECTIVE AND DESIGN: The correlation between innate immune responses and formation of cytoplasmic lipid bodies (LBs) was investigated in vivo in inflammatory macrophages from rats infected with Trypanosoma cruzi, the intracellular parasite which causes Chagas' disease. MATERIAL AND METHODS: We used an experimental model of high-dose irradiation prior to infection, which depletes the humoral and cellular immune responses except for the phagocytic activity of macrophages. Rats, irradiated or not, were infected with T. cruzi and macrophages from different origins (peritoneum, heart, uterus) were studied by transmission electron microscopy (TEM). RESULTS: As documented by quantitative TEM, innate immune responses induced prominent formation, structural changes and intracellular interactions of LBs. LBs significantly increased their size and changed their osmiophilia in response to both infection alone and when macrophages were challenged with irradiation-induced increased parasite load. Remarkably, a consistent LB-phagolysosome association was identified. LBs were surrounding, attached to or internalized by phagolysosomes. CONCLUSIONS: We demonstrated that LBs are dynamic organelles notably involved in the host response to acute T. cruzi infection, an event that may be important for pathogen control during innate immunity. Our findings highlight LBs as structural markers of the innate immune responses in phagocytic cells.

Determinação do limiar de anaerobiose de idosos saudáveis: comparação entre diferentes métodos / Determination of anaerobic threshold in healthy elderly people: comparison between different methods

OBJETIVO: Determinar o limiar de anaerobiose (LA) pelo método ventilatório (visual gráfico), pelos modelos matemáticos, Heteroscedástico e Hinkley, aplicados aos conjuntos de dados de freqüência cardíaca (FC), RMS do sinal mioelétrico (Root Mean Square) e VCO2 e comparar o LA obtido pelos três métodos. METODOLOGIA: Foram estudados 9 idosos ativos (61,4±1,8 anos) durante teste de exercício físico dinâmico contínuo do tipo rampa, em cicloergômetro, com incrementos de potência variando de 10 a 15 Watts/min. Foram coletados os dados de FC batimento a batimento, eletromiografia de superfície do músculo vasto lateral e variáveis ventilatórias respiração a respiração. Após a aplicação dos modelos matemáticos e identificados os pontos de quebra de comportamento, foram registrados neste momento os valores de potência, VO2 e FC, comparados e correlacionados aos obtidos pelo método visual gráfico (padrão ouro). Foi utilizado o teste de Friedman para comparações múltiplas e o teste de correlação de Spearman (nível de significância de 5 por cento). RESULTADOS: Não foram encontradas diferenças significantes, em relação ao padrão ouro, entre os valores de potência, VO2 e FC, no momento do LA identificado pelos diferentes modelos. Foram encontradas correlações significantes entre os valores de FC identificados pelos modelos matemáticos entre os valores de VO2 quando identificados pela freqüência cardíaca e de potência somente quando identificada pelo modelo de Hinkley aplicado aos dados de RMS do sinal mioelétrico. CONCLUSÕES: No grupo estudado, os modelos matemáticos mostraram-se adequados na determinação não-invasiva do LA, sendo que ambos ajustaram-se melhor aos dados de FC, seguido pela VCO2 e RMS.

OBJECTIVE: To determine the anaerobic threshold by the graphic visual ventilatory method and the Hinkley and heteroscedastic mathematical models, applied to heart rate, myoelectric root mean square (RMS) signal and VCO2 datasets, and to compare the anaerobic threshold obtained by the three methods. METHOD: Nine active elderly subjects were studied (aged 61.4 ± 1.8 years) during a ramp-load continuous dynamic physical exercise test on a cycle ergometer, with power ranging from 10 to 15 Watts/min. Beat-to-beat heart rate data, electromyographic data from the surface of the vastus lateralis muscle, and breath-to-breath ventilatory data were collected. After applying mathematical models and identifying the behavioral shift points, these power levels, heart rates and VO2 values were noted and these were compared and correlated with those obtained by the graphic visual model (gold standard). The Friedman test for multiple comparisons and the Spearman correlation test were utilized (significance level: 5 percent). RESULTS: No significant differences were found in relation to the gold standard, between the power levels, VO2 values and heart rates at the anaerobic threshold identified by the different models. Significant correlations were found between the heart rates identified by the mathematical models, between the VO2 values identified by the heart rates, and between power rates only when identified by the Hinkley model applied to myoelectric RMS signal data. CONCLUSION: In this study group, the mathematical models were shown to be adequate for non-invasively determining the anaerobic threshold. Both models worked best on the heart rate data, followed by VCO2 and RMS.

A contact map matching approach to protein structure similarity analysis

We modeled the problem of identifying how close two proteins are structurally by measuring the dissimilarity of their contact maps. These contact maps are colored images, in which the chromatic information encodes the chemical nature of the contacts. We studied two conceptually distinct image-processing algorithms to measure the dissimilarity between these contact maps; one was a content-based image retrieval method, and the other was based on image registration. In experiments with contact maps constructed from the protein data bank, our approach was able to identify, with greater than 80% precision, instances of monomers of apolipoproteins, globins, plastocyanins, retinol binding proteins and thioredoxins, among the monomers of Protein Data Bank Select. The image registration approach was only slightly more accurate than the content-based image retrieval approach.