Background: This article reports an experiment based on the measurement of the academic about the... more Background: This article reports an experiment based on the measurement of the academic about the use of medicinal plants is increasing, this article aims to analyze the behavior of future health professionals regarding the use of medicinal plants, since they will be responsible for the orientation and education of patients and the population. Methods: The present study involved 50 students of the academic health care Anhanguera College of Brasilia (Biological Sciences, Biomedicine, Nursing and Pharmacy), selected randomly. Questions about the use of medicinal plants were made and 96% confirmed having used medicinal plants. We used the Descriptive statistic to compare the answers. Results: Most academics reported self-consumption of medicinal plants, with a positive result after use (*p<0.001). The most used medicinal plants were, in addition to the mixture of herbs, boldo and Mexican tea, for the treatment of stomach pains, headaches, coughs, and colds. Self-usage was mainly due...
Background: This article reports an experiment based on the measurement of the academic achieveme... more Background: This article reports an experiment based on the measurement of the academic achievement of students submitted to self-experiments during practical classes compared with students who attended regular practical classes (control group) to assess whether this intervention could help assess the influence of self-experiments on student learning. Methods: This study involved 71 students in the second terms of the degree of Bachelor of Pharmaceutical Sciences, studying the Cell Biology unit. Experiments were conducted using the students themselves as subjects under conditions that mimic situations observed in daily life, fasting and ingestion of carbohydrates. The performance of students in health college student assessments and the degree of motivation in performing these experiments was assessed at the Anhanguera college, Brasilia, Brazil. In total, 33 students (46.5%) participated actively in the experiment and the rest only observed the experiment carried out by the first gr...
Background: Scientific writing guidelines recommend that a scientific text should be straightforw... more Background: Scientific writing guidelines recommend that a scientific text should be straightforward, without prolixity, and informative, without obscurity. However, the extent to which researchers follow these recommendations is unknown. Considering that the most cited journals provide more detailed instructions for authors, we aimed to investigate the degree of relative prolixity (i.e., length versus amount of information) among journals with different citation impact scores. Methods: We analyzed journals whose articles follow the classic Introduction, Method, Results, and Discussion structure, written in English and with a CiteScore value ≥ 0.01 classified in the ‘Pharmaceutical Science’ area. Relative prolixity was calculated as the ratio between the number of characters and the number of citations contained in the introductory section of original articles. Additionally, we collected the number of paragraphs and words. Results: The number of characters, words and citations in th...
Background: Active learning strategies and the use of technology in classes have been widely indi... more Background: Active learning strategies and the use of technology in classes have been widely indicated to enhance learning. Although much has been discussed on these topics, few studies have addressed them with adequate experimental designs. Therefore, this study investigated the effect of a strategy coupling active learning methodology and technology –video lectures production by students – on the students’ learning in comparison with traditional approaches. Methods: To investigate the impact of video production on students’ learning, approximately half of one class of undergraduate students in a Pharmacy program attended traditional classes on one of its modules, while the other half was instructed to elaborate video lectures about the same content. We recorded their scores in two exams on the topic covered by the video lectures, one prior to intervention and the second after the intervention. We also recorded their score in a final exam at the end of the course, which covered all...
Juvenile tegu lizards (Salvator merianae) experience gradual and mild temperature changes from au... more Juvenile tegu lizards (Salvator merianae) experience gradual and mild temperature changes from autumn to winter in their habitat. This tropical/subtropical reptile enter a state of dormancy, with an 80% reduction in metabolic rate, that remains almost constant during winter. The redox metabolism in non-mammalian vertebrates that hibernate under such distinguished conditions is poorly understood. We analyzed the redox metabolism in the intestine of juvenile tegus during different stages of their first annual cycle. The effect of food deprivation (in spring) was also studied to compare with fasting during hibernation. Both winter dormancy and food deprivation caused decreases in reduced glutathione levels and glutathione transferase activity. While glutathione peroxidase and glutathione transferase activities decreased during winter dormancy, as well as glutathione (GSH) levels, other antioxidant enzymes (catalase, superoxide dismutase and glutathione reductase) remained unchanged. No...
Humans and most mammals suffer severe damage when exposed to ischemia and reperfusion episodes du... more Humans and most mammals suffer severe damage when exposed to ischemia and reperfusion episodes due to an overproduction of reactive oxygen species (ROS). In contrast, several hypoxia/anoxia-tolerant animals survive very similar situations. We evaluated herein the redox metabolism in the anoxia-tolerant land snail Helix aspersa after catalase inhibition by 3-amino-1,2,4-triazole (ATZ) injection during a cycle of wide and abrupt change in oxygen availability. The exposure to anoxia for 5 h caused a change of only one of several parameters related to free radical metabolism: a rise in selenium-dependent glutathione peroxidase (Se-GPX) activity in muscle of both saline- and ATZ-injected animals (by 1.9- and 1.8-fold, respectively). Catalase suppression had no effect in animals under normoxia or anoxia. However, during reoxygenation catalase suppression kept high levels of muscle Se-GPX activity (twofold higher than in saline-injected snails up to 30 min reoxygenation) and induced the increase in hepatopancreas SOD activity (by 22 %), indicating higher levels of ROS in both organs than in saline-injected animals. Additionally, catalase-suppressed snails showed 12 % higher levels of carbonyl protein-a sign of mild oxidative stress-in muscle during reoxygenation than those animals with intact catalase. No changes were observed in glutathione parameters (GSH, GSSG and GSSG:GSH ratio), TBARS, and GST activity in any of the experimental groups, in both organs. These results indicate that catalase inhibition inflicts changes in the free radical metabolism during reoxygenation, prompting a stress-response that is a reorganization in other enzymatic antioxidant defenses to minimize alterations in the redox homeostasis in land snails.
Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology, 2003
This study explored the effects of fasting on body fuel mobilization in the common vampire bat (D... more This study explored the effects of fasting on body fuel mobilization in the common vampire bat (Desmodus rotundus) fed a high-protein diet (bovine blood). An uncommon fragility during food deprivation has been reported for this species to the point of untimely deaths after only 2-3 nights of fasting. The immediate biochemical responses to fasting, however, have not been established. Thus, blood glucose, plasma FFA, glycogen, protein, and fat concentrations in the liver and muscles were determined in fed and 24-, 48- and 72 h-fasted individuals. The results indicate that D. rotundus is unable to maintain adequate levels of blood glucose during fasting, probably due to low tissue stores of energy fuels or difficulty in mobilizing them. Other factors may play an important role in this species abundance, such as the previously reported behavior of reciprocal blood regurgitation.
Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2013
Large changes in oxygen availability in aquatic environments, ranging from anoxia through to hype... more Large changes in oxygen availability in aquatic environments, ranging from anoxia through to hyperoxia, can lead to corresponding wide variation in the production of reactive oxygen species (ROS) by animals with aquatic respiration. Therefore, animals living in marine, estuarine and freshwater environments have developed efficient antioxidant defenses to minimize oxidative stress and to regulate the cellular actions of ROS. Changes in oxygen levels may lead to bursts of ROS generation that can be particularly harmful. This situation is commonly experienced by aquatic animals during abrupt transitions from periods of hypoxia/anoxia back to oxygenated conditions (e.g. intertidal cycles). The strategies developed differ significantly among aquatic species and are (i) improvement of their endogenous antioxidant system under hyperoxia (that leads to increased ROS formation) or other similar ROS-related stresses, (ii) increase in antioxidant levels when displaying higher metabolic rates, (iii) presence of constitutively high levels of antioxidants, that attenuates oxidative stress derived from fluctuations in oxygen availability, or (iv) increase in the activity of antioxidant enzymes (and/or the levels of their mRNAs) during hypometabolic states associated with anoxia/hypoxia. This enhancement of the antioxidant system - coined over a decade ago as &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;preparation for oxidative stress&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; - controls the possible harmful effects of increased ROS formation during hypoxia/reoxygenation. The present article proposes a novel explanation for the biochemical and molecular mechanisms involved in this phenomenon that could be triggered by hypoxia-induced ROS formation. We also discuss the connections among oxygen sensing, oxidative damage and regulation of the endogenous antioxidant defense apparatus in animals adapted to many natural or man-made challenges of the aquatic environment.
ABSTRACT This chapter contains sections titled: Estuarine/Intertidal HabitatsTemperature Increase... more ABSTRACT This chapter contains sections titled: Estuarine/Intertidal HabitatsTemperature Increase as Stress InducerVariation of Environmental Oxygen Levels, Especially Hypoxia-Reoxygenation as a Stress InducerSalinity Variation as a Stress InducerPost-Transcriptional and Post-Translational Controls on Antioxidant EnzymesOxidative Stress and Transcription Factor Control of Gene ExpressionOxidative Stress and Gene Screening in Marine and Estuarine OrganismsConclusion References
AJP Regulatory Integrative and Comparative Physiology
The specific contribution of each antioxidant enzyme to protection against the reoxygenation-asso... more The specific contribution of each antioxidant enzyme to protection against the reoxygenation-associated oxidative stress after periods of hypoxia is not well understood. We assessed the physiological role of catalase during posthypoxic reoxygenation by the combination of two approaches. First, catalase activity of Nile tilapias (Oreochromis niloticus) was 90% suppressed by intraperitoneal injection of 3-amino-1,2,4-triazole (ATZ, 1g/kg). In ATZ-injected fish, liver GSH levels, oxidative stress markers, and activities of other antioxidant enzymes remained unchanged. Second, animals with depleted catalase activity (or those saline-injected) were subjected to a cycle of severe hypoxia (dissolved O(2) = 0.28 mg/l for 3 h) followed by reoxygenation (0.5 to 24 h). Hypoxia did not induce changes in the above-mentioned parameters, either in saline- or in ATZ-injected animals. Reoxygenation increased superoxide dismutase activity in saline-injected fish, whose levels were similar to ATZ-inje...
Background: This article reports an experiment based on the measurement of the academic about the... more Background: This article reports an experiment based on the measurement of the academic about the use of medicinal plants is increasing, this article aims to analyze the behavior of future health professionals regarding the use of medicinal plants, since they will be responsible for the orientation and education of patients and the population. Methods: The present study involved 50 students of the academic health care Anhanguera College of Brasilia (Biological Sciences, Biomedicine, Nursing and Pharmacy), selected randomly. Questions about the use of medicinal plants were made and 96% confirmed having used medicinal plants. We used the Descriptive statistic to compare the answers. Results: Most academics reported self-consumption of medicinal plants, with a positive result after use (*p<0.001). The most used medicinal plants were, in addition to the mixture of herbs, boldo and Mexican tea, for the treatment of stomach pains, headaches, coughs, and colds. Self-usage was mainly due...
Background: This article reports an experiment based on the measurement of the academic achieveme... more Background: This article reports an experiment based on the measurement of the academic achievement of students submitted to self-experiments during practical classes compared with students who attended regular practical classes (control group) to assess whether this intervention could help assess the influence of self-experiments on student learning. Methods: This study involved 71 students in the second terms of the degree of Bachelor of Pharmaceutical Sciences, studying the Cell Biology unit. Experiments were conducted using the students themselves as subjects under conditions that mimic situations observed in daily life, fasting and ingestion of carbohydrates. The performance of students in health college student assessments and the degree of motivation in performing these experiments was assessed at the Anhanguera college, Brasilia, Brazil. In total, 33 students (46.5%) participated actively in the experiment and the rest only observed the experiment carried out by the first gr...
Background: Scientific writing guidelines recommend that a scientific text should be straightforw... more Background: Scientific writing guidelines recommend that a scientific text should be straightforward, without prolixity, and informative, without obscurity. However, the extent to which researchers follow these recommendations is unknown. Considering that the most cited journals provide more detailed instructions for authors, we aimed to investigate the degree of relative prolixity (i.e., length versus amount of information) among journals with different citation impact scores. Methods: We analyzed journals whose articles follow the classic Introduction, Method, Results, and Discussion structure, written in English and with a CiteScore value ≥ 0.01 classified in the ‘Pharmaceutical Science’ area. Relative prolixity was calculated as the ratio between the number of characters and the number of citations contained in the introductory section of original articles. Additionally, we collected the number of paragraphs and words. Results: The number of characters, words and citations in th...
Background: Active learning strategies and the use of technology in classes have been widely indi... more Background: Active learning strategies and the use of technology in classes have been widely indicated to enhance learning. Although much has been discussed on these topics, few studies have addressed them with adequate experimental designs. Therefore, this study investigated the effect of a strategy coupling active learning methodology and technology –video lectures production by students – on the students’ learning in comparison with traditional approaches. Methods: To investigate the impact of video production on students’ learning, approximately half of one class of undergraduate students in a Pharmacy program attended traditional classes on one of its modules, while the other half was instructed to elaborate video lectures about the same content. We recorded their scores in two exams on the topic covered by the video lectures, one prior to intervention and the second after the intervention. We also recorded their score in a final exam at the end of the course, which covered all...
Juvenile tegu lizards (Salvator merianae) experience gradual and mild temperature changes from au... more Juvenile tegu lizards (Salvator merianae) experience gradual and mild temperature changes from autumn to winter in their habitat. This tropical/subtropical reptile enter a state of dormancy, with an 80% reduction in metabolic rate, that remains almost constant during winter. The redox metabolism in non-mammalian vertebrates that hibernate under such distinguished conditions is poorly understood. We analyzed the redox metabolism in the intestine of juvenile tegus during different stages of their first annual cycle. The effect of food deprivation (in spring) was also studied to compare with fasting during hibernation. Both winter dormancy and food deprivation caused decreases in reduced glutathione levels and glutathione transferase activity. While glutathione peroxidase and glutathione transferase activities decreased during winter dormancy, as well as glutathione (GSH) levels, other antioxidant enzymes (catalase, superoxide dismutase and glutathione reductase) remained unchanged. No...
Humans and most mammals suffer severe damage when exposed to ischemia and reperfusion episodes du... more Humans and most mammals suffer severe damage when exposed to ischemia and reperfusion episodes due to an overproduction of reactive oxygen species (ROS). In contrast, several hypoxia/anoxia-tolerant animals survive very similar situations. We evaluated herein the redox metabolism in the anoxia-tolerant land snail Helix aspersa after catalase inhibition by 3-amino-1,2,4-triazole (ATZ) injection during a cycle of wide and abrupt change in oxygen availability. The exposure to anoxia for 5 h caused a change of only one of several parameters related to free radical metabolism: a rise in selenium-dependent glutathione peroxidase (Se-GPX) activity in muscle of both saline- and ATZ-injected animals (by 1.9- and 1.8-fold, respectively). Catalase suppression had no effect in animals under normoxia or anoxia. However, during reoxygenation catalase suppression kept high levels of muscle Se-GPX activity (twofold higher than in saline-injected snails up to 30 min reoxygenation) and induced the increase in hepatopancreas SOD activity (by 22 %), indicating higher levels of ROS in both organs than in saline-injected animals. Additionally, catalase-suppressed snails showed 12 % higher levels of carbonyl protein-a sign of mild oxidative stress-in muscle during reoxygenation than those animals with intact catalase. No changes were observed in glutathione parameters (GSH, GSSG and GSSG:GSH ratio), TBARS, and GST activity in any of the experimental groups, in both organs. These results indicate that catalase inhibition inflicts changes in the free radical metabolism during reoxygenation, prompting a stress-response that is a reorganization in other enzymatic antioxidant defenses to minimize alterations in the redox homeostasis in land snails.
Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology, 2003
This study explored the effects of fasting on body fuel mobilization in the common vampire bat (D... more This study explored the effects of fasting on body fuel mobilization in the common vampire bat (Desmodus rotundus) fed a high-protein diet (bovine blood). An uncommon fragility during food deprivation has been reported for this species to the point of untimely deaths after only 2-3 nights of fasting. The immediate biochemical responses to fasting, however, have not been established. Thus, blood glucose, plasma FFA, glycogen, protein, and fat concentrations in the liver and muscles were determined in fed and 24-, 48- and 72 h-fasted individuals. The results indicate that D. rotundus is unable to maintain adequate levels of blood glucose during fasting, probably due to low tissue stores of energy fuels or difficulty in mobilizing them. Other factors may play an important role in this species abundance, such as the previously reported behavior of reciprocal blood regurgitation.
Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2013
Large changes in oxygen availability in aquatic environments, ranging from anoxia through to hype... more Large changes in oxygen availability in aquatic environments, ranging from anoxia through to hyperoxia, can lead to corresponding wide variation in the production of reactive oxygen species (ROS) by animals with aquatic respiration. Therefore, animals living in marine, estuarine and freshwater environments have developed efficient antioxidant defenses to minimize oxidative stress and to regulate the cellular actions of ROS. Changes in oxygen levels may lead to bursts of ROS generation that can be particularly harmful. This situation is commonly experienced by aquatic animals during abrupt transitions from periods of hypoxia/anoxia back to oxygenated conditions (e.g. intertidal cycles). The strategies developed differ significantly among aquatic species and are (i) improvement of their endogenous antioxidant system under hyperoxia (that leads to increased ROS formation) or other similar ROS-related stresses, (ii) increase in antioxidant levels when displaying higher metabolic rates, (iii) presence of constitutively high levels of antioxidants, that attenuates oxidative stress derived from fluctuations in oxygen availability, or (iv) increase in the activity of antioxidant enzymes (and/or the levels of their mRNAs) during hypometabolic states associated with anoxia/hypoxia. This enhancement of the antioxidant system - coined over a decade ago as &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;preparation for oxidative stress&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; - controls the possible harmful effects of increased ROS formation during hypoxia/reoxygenation. The present article proposes a novel explanation for the biochemical and molecular mechanisms involved in this phenomenon that could be triggered by hypoxia-induced ROS formation. We also discuss the connections among oxygen sensing, oxidative damage and regulation of the endogenous antioxidant defense apparatus in animals adapted to many natural or man-made challenges of the aquatic environment.
ABSTRACT This chapter contains sections titled: Estuarine/Intertidal HabitatsTemperature Increase... more ABSTRACT This chapter contains sections titled: Estuarine/Intertidal HabitatsTemperature Increase as Stress InducerVariation of Environmental Oxygen Levels, Especially Hypoxia-Reoxygenation as a Stress InducerSalinity Variation as a Stress InducerPost-Transcriptional and Post-Translational Controls on Antioxidant EnzymesOxidative Stress and Transcription Factor Control of Gene ExpressionOxidative Stress and Gene Screening in Marine and Estuarine OrganismsConclusion References
AJP Regulatory Integrative and Comparative Physiology
The specific contribution of each antioxidant enzyme to protection against the reoxygenation-asso... more The specific contribution of each antioxidant enzyme to protection against the reoxygenation-associated oxidative stress after periods of hypoxia is not well understood. We assessed the physiological role of catalase during posthypoxic reoxygenation by the combination of two approaches. First, catalase activity of Nile tilapias (Oreochromis niloticus) was 90% suppressed by intraperitoneal injection of 3-amino-1,2,4-triazole (ATZ, 1g/kg). In ATZ-injected fish, liver GSH levels, oxidative stress markers, and activities of other antioxidant enzymes remained unchanged. Second, animals with depleted catalase activity (or those saline-injected) were subjected to a cycle of severe hypoxia (dissolved O(2) = 0.28 mg/l for 3 h) followed by reoxygenation (0.5 to 24 h). Hypoxia did not induce changes in the above-mentioned parameters, either in saline- or in ATZ-injected animals. Reoxygenation increased superoxide dismutase activity in saline-injected fish, whose levels were similar to ATZ-inje...
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