A Novel Non-invasive Approach for Measuring Upper Airway Collapsibility in Mice

Introduction: Invasive procedures were previously developed for measuring pharyngeal collapsibility in rodents during expiration, when declining neuromuscular activity makes the airway unstable. We developed a non-invasive approach for streamlining collapsibility measurements by characterizing responses in physiologic markers of dynamic expiratory airflow obstruction to negative nasal pressure challenges.Methods: Anesthetized mice were instrumented to monitor upper airway pressure-flow relationships with head-out plethysmography while nasal pressure was ramped down from ~ +5 to −20 cm H2O over several breaths. Inspiratory and expiratory flow, volume, and timing characteristics were assessed breath-wise. Pcrit was estimated at transitions in expiratory amplitude and timing parameters, and compared to gold standard PCRIT measurements when nasal and tracheal pressures diverged during expiration. Predictions equations were constructed in a development data set (n = 8) and applied prospectively to a validation data set (n = 16) to estimate gold standard PCRIT.Results: The development data demonstrated that abrupt reversals in expiratory duration and tidal volume during nasal pressure ramps predicted gold standard PCRIT measurements. After applying regression equations from the development to a validation dataset, we found that a combination of expiratory amplitude and timing parameters proved to be robust predictors of gold standard PCRIT with minimal bias and narrow confidence intervals.Conclusions: Markers of expiratory airflow obstruction can be used to model upper airway collapsibility, and can provide sensitive measures of changes in airway collapsibility in rodents. This approach streamlines repeated non-invasive PCRIT measurements, and facilitates studies examining the impact of genetic, environmental, and pharmacologic factors on upper airway control

Descriptive of Brazilian Journals implemented in Open Journal Systems

Open Journal System (OJS) is widely used in Brazil, with journals in various disciplines linked to various institutions, on portals or stand alone installations. This scenario presents an opportunity to journal's studies, requiring approaches that enable comprehension of this diversity. Therefore, this study aims to describe the use of OJS in Brazil, regarding versions, areas of knowledge, use of Digital Object Identifier (DOI), among others aspects. The study contributes to the knowledge of the use of free tools in the context of Brazilian scientific communication under a quantitative approach, using computer processing, due to the amount of selected journals. As a result, it was revealed that Brazil has 1,827 OJS journals, but only 1,637 are active. Similarly, most of magazines are on the most current version (2.4). Social sciences are the ​​knowledge area that have the highest number of journals; on its turn, the use of DOI can be seen as incipient, but promising. A complex scenario, but with opportunities for more detailed studies, given the growth of Brazilian research, with great use of OJS on the creation of open access journals

Guia do usuário do OJS 3

The present work is an adaptation and expansion of the official documentation of the Open Journal Systems (OJS), published by the Public Knowledge Project (PKP) and available entirely on the internet, freely, with the necessary adjustments to the Portuguese language of Brazil and to the context of the Brazilian publication.A presente obra é uma adaptação e ampliação da documentação oficial do Open Journal Systems (OJS), publicada pelo Public Knowledge Project (PKP) e disponível integralmente na internet, de forma livre, com os ajustes necessários a língua portuguesa do Brasil e ao contexto da publicação brasileira

Intranasal leptin relieves sleep-disordered breathing in mice with diet-induced obesity

Copyright © 2019 by the American Thoracic Society. Rationale: Leptin treats upper airway obstruction and alveolar hypoventilation in leptin-deficient ob/ob mice. However, obese humans and mice with diet-induced obesity (DIO) are resistant to leptin because of poor permeability of the blood–brain barrier. We propose that intranasal leptin will bypass leptin resistance and treat sleep-disordered breathing in obesity. Objectives: To assess if intranasal leptin can treat obesity hypoventilation and upper airway obstruction during sleep in mice with DIO. Methods: Male C57BL/6J mice were fed with a high-fat diet for 16 weeks. A single dose of leptin (0.4 mg/kg) or BSA (vehicle) were administered intranasally or intraperitoneally, followed by either sleep studies (n = 10) or energy expenditure measurements (n = 10). A subset of mice was treated with leptin daily for 14 days for metabolic outcomes (n = 20). In a separate experiment, retrograde viral tracers were used to examine connections between leptin receptors and respiratory motoneurons. Measurements and Main Results: Acute intranasal, but not intraperitoneal, leptin decreased the number of oxygen desaturation events in REM sleep, and increased ventilation in non-REM and REM sleep, independently of metabolic effects. Chronic intranasal leptin decreased food intake and body weight, whereas intraperitoneal leptin had no effect. Intranasal leptin induced signal transducer and activator of transcription 3 phosphorylation in hypothalamic and medullary centers, whereas intraperitoneal leptin had no effect. Leptin receptor–positive cells were synaptically connected to respiratory motoneurons. Conclusions: In mice with DIO, intranasal leptin bypassed leptin resistance and significantly attenuated sleep-disordered breathing independently of body weight

Intranasal Leptin Relieves Sleep Disordered Breathing in Mice with Diet Induced Obesity.

Copyright © 2019 by the American Thoracic Society. Rationale: Leptin treats upper airway obstruction and alveolar hypoventilation in leptin-deficient ob/ob mice. However, obese humans and mice with diet-induced obesity (DIO) are resistant to leptin because of poor permeability of the blood–brain barrier. We propose that intranasal leptin will bypass leptin resistance and treat sleep-disordered breathing in obesity. Objectives: To assess if intranasal leptin can treat obesity hypoventilation and upper airway obstruction during sleep in mice with DIO. Methods: Male C57BL/6J mice were fed with a high-fat diet for 16 weeks. A single dose of leptin (0.4 mg/kg) or BSA (vehicle) were administered intranasally or intraperitoneally, followed by either sleep studies (n = 10) or energy expenditure measurements (n = 10). A subset of mice was treated with leptin daily for 14 days for metabolic outcomes (n = 20). In a separate experiment, retrograde viral tracers were used to examine connections between leptin receptors and respiratory motoneurons. Measurements and Main Results: Acute intranasal, but not intraperitoneal, leptin decreased the number of oxygen desaturation events in REM sleep, and increased ventilation in non-REM and REM sleep, independently of metabolic effects. Chronic intranasal leptin decreased food intake and body weight, whereas intraperitoneal leptin had no effect. Intranasal leptin induced signal transducer and activator of transcription 3 phosphorylation in hypothalamic and medullary centers, whereas intraperitoneal leptin had no effect. Leptin receptor–positive cells were synaptically connected to respiratory motoneurons. Conclusions: In mice with DIO, intranasal leptin bypassed leptin resistance and significantly attenuated sleep-disordered breathing independently of body weight

Geobiological and diagenetic insights from Malvinokaffric devonian biota (Chapada Group, Paran? Basin, Brazil) : paleobiological and paleoenvironmental implications.

This study tests the presence of differential preservation in the Devonian Malvinokaffric fauna from the Chapada Group (Parana? Basin, Brazil). Results of EDXRF, EDS, Raman Spectroscopy, and petrographic analyses show differential preservation of shells that were originally calcite as hematite and goethite fossils, while organisms with original calcium phosphate shells tend to be preserved inside phosphatic concretions. Both preservation types are commonly associated with pseudoframboids, while calcium sulfate minerals are commonly associated with hematized fossils. From this evidence, a diagenetic model for these fossils is proposed. The model includes an early diagenetic phase (characterized by anaerobic sulfate reduction and precipitation of pyrite and carbonate-fluorapatite) and a second, near-surface chemical weathering phase (characterized by the oxidation of pyrite and precipitation of iron oxyhydroxides and calcium sulfates). Acidic conditions in both phases may account for the dissolution of less stable minerals compared to calcium phosphate. It is considered that this model may assist in understanding other similarly preserved biotas, as well as enhancing understanding of the taphonomic overprint that may occur within this important and endemic Devonian biota

Melhoria contínua e aprendizagem organizacional: múltiplos casos em empresas do setor automobilístico Continuous improvement and organizational learning: multiple cases in automotive industry companies

A acirrada competição, ressaltada pela disputa globalizada, exige que as organizações estabeleçam inovações cada vez mais frequentes e rápidas a fim de atender às mudanças tecnológicas, econômicas e políticas que a sociedade atravessa. Neste contexto, a melhoria contínua dos produtos e processos produtivos é necessária para manter a empresa competitiva, entretanto, muitas destas iniciativas fracassam dentro das organizações. Com o objetivo de analisar como os mecanismos de aprendizagem sustentam as atividades de melhoria, é realizada uma pesquisa de campo, baseada no estudo de caso em três empresas do setor automobilístico. O artigo conclui que, além de implantar programas e ferramentas para resolução de problemas, as organizações precisam desenvolver ambientes que estimulem a aprendizagem e a cooperação entre seus indivíduos, trabalhando no desenvolvimento dos recursos humanos para que as iniciativas de melhoria sejam, de fato, contínuas.<br>Fierce competition, highlighted by global competition has increasingly required organizations to adopt frequent and quick innovations to meet the current technological, economic, and political changes in society. Accordingly , the continuous improvement of products and production processes is necessary to keep the company competitive. However, many of these initiatives fail in organizations. In order to analyze how the mechanisms of learning support improvement activities, a field research based on case study of three companies in the automotive sector was carried out. The article concludes that in addition to programs and tools for solving problems, organizations need to develop environments that encourage learning and cooperation among its individuals working in human resources development to achieve continuous improvement