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1.
Biol. Res ; 52: 14, 2019. graf
Article in English | LILACS | ID: biblio-1011416

ABSTRACT

BACKGROUND: Drought is a major abiotic stress affecting global wheat (Triticum aestivum L.) production. Exploration of drought-tolerant genes is essential for the genetic improvement of drought tolerance in wheat. Previous studies have shown that some histone encoding genes are involved in plant drought tolerance. However, whether the H2B family genes are involved in drought stress response remains unclear. METHODS: Here, we identified a wheat histone H2B family gene, TaH2B-7D, which was significantly up-regulated under drought stress conditions. Virus-induced gene silencing (VIGS) technology was used to further verify the function of TaH2B-7D in wheat drought tolerance. The phenotypic and physiological changes were examined in the TaH2B-7D knock-down plants. RESULTS: In the TaH2B-7D knock-down plants, relative electrolyte leakage rate and malonaldehyde (MDA) content significantly increased, while relative water content (RWC) and proline content significantly decreased compared with those in the non-knocked-down plants under drought stress conditions. TaH2B-7D knock-down plants exhibited severe sagging, wilting and dwarf phenotypes under drought stress conditions, but not in the non-knocked-down plants, suggesting that the former were more sensitive to drought stress. CONCLUSION: These results indicate that TaH2B-7D potentially plays a vital role in conferring drought tolerance in wheat.


Subject(s)
Plant Proteins/genetics , Stress, Physiological/genetics , Triticum/genetics , Gene Expression Regulation, Plant/genetics , Gene Silencing , Droughts , Phenotype , Plant Proteins/metabolism , Stress, Physiological/physiology , Triticum/metabolism , Plants, Genetically Modified/genetics , Plant Physiological Phenomena/genetics , Real-Time Polymerase Chain Reaction
2.
Biol. Res ; 52: 20, 2019. tab, graf
Article in English | LILACS | ID: biblio-1011422

ABSTRACT

BACKGROUND: Histone acetylation is an important epigenetic modification that regulates gene activity in response to stress. Histone acetylation levels are reversibly regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs). The imperative roles of HDACs in gene transcription, transcriptional regulation, growth and responses to stressful environment have been widely investigated in Arabidopsis. However, data regarding HDACs in kenaf crop has not been disclosed yet. RESULTS: In this study, six HDACs genes (HcHDA2, HcHDA6, HcHDA8, HcHDA9, HcHDA19, and HcSRT2) were isolated and characterized. Phylogenetic tree revealed that these HcHDACs shared high degree of sequence homology with those of Gossypium arboreum. Subcellular localization analysis showed that GFP-tagged HcHDA2 and HcHDA8 were predominantly localized in the nucleus, HcHDA6 and HcHDA19 in nucleus and cytosol. The HcHDA9 was found in both nucleus and plasma membranes. Real-time quantitative PCR showed that the six HcHDACs genes were expressed with distinct expression patterns across plant tissues. Furthermore, we determined differential accumulation of HcHDACs transcripts under salt and drought treatments, indicating that these enzymes may participate in the biological process under stress in kenaf. Finally, we showed that the levels of histone H3 and H4 acetylation were modulated by salt and drought stress in kenaf. CONCLUSIONS: We have isolated and characterized six HDACs genes from kenaf. These data showed that HDACs are imperative players for growth and development as well abiotic stress responses in kenaf.


Subject(s)
Stress, Physiological/physiology , Hibiscus/enzymology , Histone Acetyltransferases/physiology , Droughts , Histone Deacetylases/physiology , Transcriptional Activation/physiology , Cloning, Molecular , Hibiscus/growth & development , Hibiscus/physiology , Real-Time Polymerase Chain Reaction
3.
Biol. Res ; 52: 39, 2019. tab, graf
Article in English | LILACS | ID: biblio-1019503

ABSTRACT

In the growth condition(s) of plants, numerous secondary metabolites (SMs) are produced by them to serve variety of cellular functions essential for physiological processes, and recent increasing evidences have implicated stress and defense response signaling in their production. The type and concentration(s) of secondary molecule(s) produced by a plant are determined by the species, genotype, physiology, developmental stage and environmental factors during growth. This suggests the physiological adaptive responses employed by various plant taxonomic groups in coping with the stress and defensive stimuli. The past recent decades had witnessed renewed interest to study abiotic factors that influence secondary metabolism during in vitro and in vivo growth of plants. Application of molecular biology tools and techniques are facilitating understanding the signaling processes and pathways involved in the SMs production at subcellular, cellular, organ and whole plant systems during in vivo and in vitro growth, with application in metabolic engineering of biosynthetic pathways intermediates.


Subject(s)
Plant Growth Regulators/metabolism , Stress, Physiological/physiology , Plant Physiological Phenomena , Secondary Metabolism/physiology , Plants/metabolism , Signal Transduction , Plant Shoots/metabolism , Plant Roots/metabolism , Gene Expression Regulation, Plant/physiology , Cell Culture Techniques
4.
Rev. bras. ter. intensiva ; 30(3): 286-293, jul.-set. 2018. tab
Article in Portuguese | LILACS | ID: biblio-977969

ABSTRACT

RESUMO Objetivo: Verificar a incidência da hiperglicemia de estresse em crianças em condição grave e investigar a etiologia da hiperglicemia com base em um modelo de avaliação da homeostasia. Métodos: Estudo prospectivo de coorte, conduzido em uma unidade de terapia intensiva pediátrica da Cairo University, que incluiu 60 crianças com doença grave e 21 controles saudáveis. Utilizaram-se os níveis séricos de glicose, insulina e peptídeo C, avaliados em até 24 horas após a admissão. O modelo de avaliação da homeostasia foi utilizado para analisar a função das células beta e a sensibilidade à insulina. Resultados: A hiperglicemia foi estimada em 70% dos pacientes. Valores de glicemia ≥ 180mg/dL se associaram com desfechos piores. Os níveis de glicemia se correlacionaram de forma positiva com o Pediatric Risk for Mortality (PRISM III) e o número de órgãos com disfunção (p = 0,019 e p = 0,022, respectivamente), enquanto os níveis de insulina se correlacionaram de forma negativa com o número de órgãos com disfunção (r = -0,33; p = 0,01). O modelo de avaliação da homeostasia revelou que 26 (43,3%) das crianças em condições graves tinham baixa função de células beta e 18 (30%) baixa sensibilidade à insulina. Detectou-se patologia combinada em apenas dois (3,3%) pacientes. Baixa função de células beta se associou de forma significante com a presença de disfunção de múltiplos órgãos, disfunção respiratória, cardiovascular e hematológica, e presença de sepse. Conclusões: A disfunção de células beta pareceu ser prevalente em nossa coorte e se associou com disfunção de múltiplos órgãos.


ABSTRACT Objective: This study aimed to study the incidence of stress hyperglycemia in critically ill children and to investigate the etiological basis of the hyperglycemia based on homeostasis model assessment. Methods: This was a prospective cohort study in one of the pediatric intensive care units of Cairo University, including 60 critically ill children and 21 healthy controls. Serum blood glucose, insulin, and C-peptide levels were measured within 24 hours of admission. Homeostasis model assessment was used to assess β-cell function and insulin sensitivity. Results: Hyperglycemia was estimated in 70% of patients. Blood glucose values ≥ 180mg/dL were associated with a poor outcome. Blood glucose levels were positively correlated with Pediatric Risk for Mortality (PRISM III) score and number of organ dysfunctions (p = 0.019 and p = 0.022, respectively), while insulin levels were negatively correlated with number of organ dysfunctions (r = −0.33, p = 0.01). Homeostasis model assessment revealed that 26 (43.3%) of the critically ill patients had low β-cell function, and 18 (30%) had low insulin sensitivity. Combined pathology was detected in 2 (3.3%) patients only. Low β-cell function was significantly associated with the presence of multi-organ dysfunction; respiratory, cardiovascular, and hematological dysfunctions; and the presence of sepsis. Conclusions: β-Cell dysfunction appeared to be prevalent in our cohort and was associated with multi-organ dysfunction.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Stress, Physiological/physiology , Sepsis/complications , Hyperglycemia/etiology , Multiple Organ Failure/physiopathology , Blood Glucose/metabolism , C-Peptide/blood , Intensive Care Units, Pediatric , Case-Control Studies , Incidence , Prospective Studies , Cohort Studies , Critical Illness , Sepsis/epidemiology , Egypt , Insulin-Secreting Cells/pathology , Homeostasis , Hyperglycemia/epidemiology , Insulin/blood , Multiple Organ Failure/epidemiology
5.
Acta cir. bras ; 33(9): 806-815, Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-973500

ABSTRACT

Abstract Purpose: To evaluate the effects of oxidative stress in pregnant rats submitted to acute and chronic stress, relating to alterations in the uterus, placenta and fetus. Methods: Twenty-four female Wistar albino (Rattus norvegicus), were divided into four groups, for induction of oxidative stress the animals were submitted to cold and physical immobilization. Plasma fasting glucose and MDA were determined in all groups and the fetuses and placentas were measured. Results: There were no statistical differences in the levels of malonic dialdehyde (MDA), however the averages of chronic stress group were higher compared to control groups, which could explain the observed adverse effects; there was no correlation between puppies' size, the weight of the placenta and MDA values. Conclusions: Chronic stress causes adverse effects, when compared to control groups; chronic stress group had fetuses, placentas and number of puppies, significantly lower compared to other groups. The rats exposed to chronic stress, also presented a higher frequency of fetal resorption.


Subject(s)
Animals , Male , Female , Pregnancy , Rats , Placenta/physiopathology , Stress, Physiological/physiology , Uterus/physiopathology , Lipid Peroxidation/physiology , Oxidative Stress/physiology , Fetus/physiopathology , Blood Glucose/analysis , Acute Disease , Chronic Disease , Rats, Wistar , Fetal Weight/physiology , Disease Models, Animal
6.
Biol. Res ; 51: 47, 2018. tab, graf
Article in English | LILACS | ID: biblio-983951

ABSTRACT

Increased levels of greenhouse gases in the atmosphere and associated climatic variability is primarily responsible for inducing heat waves, flooding and drought stress. Among these, water scarcity is a major limitation to crop productivity. Water stress can severely reduce crop yield and both the severity and duration of the stress are critical. Water availability is a key driver for sustainable cotton production and its limitations can adversely affect physiological and biochemical processes of plants, leading towards lint yield reduction. Adaptation of crop husbandry techniques suitable for cotton crop requires a sound understanding of environmental factors, influencing cotton lint yield and fiber quality. Various defense mechanisms e.g. maintenance of membrane stability, carbon fixation rate, hormone regulation, generation of antioxidants and induction of stress proteins have been found play a vital role in plant survival under moisture stress. Plant molecular breeding plays a functional role to ascertain superior genes for important traits and can offer breeder ready markers for developing ideotypes. This review highlights drought-induced damage to cotton plants at structural, physiological and molecular levels. It also discusses the opportunities for increasing drought tolerance in cotton either through modern gene editing technology like clustered regularly interspaced short palindromic repeat (CRISPR/Cas9), zinc finger nuclease, molecular breeding as well as through crop management, such as use of appropriate fertilization, growth regulator application and soil amendments.


Subject(s)
Stress, Physiological/physiology , Adaptation, Physiological/physiology , Plants, Genetically Modified/physiology , Gene Expression Regulation, Plant/physiology , Gossypium/physiology , Droughts , Stress, Physiological/genetics , Adaptation, Physiological/genetics , Plants, Genetically Modified/genetics , Gene Expression Regulation, Plant/genetics , Gossypium/genetics , Acclimatization/genetics
7.
Biol. Res ; 51: 46, 2018. tab, graf
Article in English | LILACS | ID: biblio-983950

ABSTRACT

The negative effects of environmental stresses, such as low temperature, high temperature, salinity, drought, heavy metal stress, and biotic stress significantly decrease crop productivity. Plant hormones are currently being used to induce stress tolerance in a variety of plants. Brassinosteroids (commonly known as BR) are a group of phytohormones that regulate a wide range of biological processes that lead to tolerance of various stresses in plants. BR stimulate BRASSINAZOLE RESISTANCE 1 (BZR1)/BRI1-EMS SUPPRESSOR 1 (BES1), transcription factors that activate thousands of BR-targeted genes. BR regulate antioxidant enzyme activities, chlorophyll contents, photosynthetic capacity, and carbohydrate metabolism to increase plant growth under stress. Mutants with BR defects have shortened root and shoot developments. Exogenous BR application increases the biosynthesis of endogenous hormones such as indole-3-acetic acid, abscisic acid, jasmonic acid, zeatin riboside, brassinosteroids (BR), and isopentenyl adenosine, and gibberellin (GA) and regulates signal transduction pathways to stimulate stress tolerance. This review will describe advancements in knowledge of BR and their roles in response to different stress conditions in plants.


Subject(s)
Stress, Physiological/physiology , Transcription Factors/genetics , Signal Transduction/genetics , Gene Expression Regulation, Plant/genetics , Brassinosteroids/metabolism , Stress, Physiological/genetics , Signal Transduction/physiology , Gene Expression Regulation, Plant/physiology
8.
Biol. Res ; 51: 43, 2018. tab, graf
Article in English | LILACS | ID: biblio-983944

ABSTRACT

BACKGROUND: CircRNAs are widespread in plants and play important roles in response to abiotic stresses. Low nitrogen (LN) promotes the growth of plant root system, allowing it to explore more nitrogen. However, whether circRNAs involved in the response to LN stress and the regulation of LN-promoted root growth in wheat remains unclear. METHODS: Two wheat varieties (LH9 and XN979) with contrasting root phenotypes to LN stress were used as materials to identify circRNAs under control and LN conditions by using high-throughput sequencing technology. RESULTS: Six differentially expressed circRNAs (DECs) involved in the common response to LN stress and 23 DECs involved in the regulation of LN-promoted root growth were successfully identified. GO analysis of the DEC-host genes involved in the regulation of LN-promoted root growth showed that GO terms related to biological regulation, responses to stimuli and signalling were significantly enriched. Moreover, seven DECs were predicted to have miRNA binding sites and may serve as miRNA sponges to capture miRNAs from their target genes. CONCLUSIONS: LN stress altered the expression profiles of circRNAs in wheat. This is the first report of LN stress responsive circRNAs in plants. Our results provided new clues for investigating the functions of circRNAs in response to LN stress and in the regulation of LN-promoted wheat root growth.


Subject(s)
Stress, Physiological/physiology , Triticum/growth & development , RNA/isolation & purification , Plant Roots/growth & development , Gene Expression Regulation, Plant/physiology , Nitrogen/metabolism , Triticum/physiology , RNA/metabolism , RNA, Circular
9.
Clinics ; 73: e256, 2018. tab, graf
Article in English | LILACS | ID: biblio-952810

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate systemic inflammatory factors and their relation to success or failure in a spontaneous ventilation test. METHODS: This cross-sectional study included a sample of 54 adult patients. Demographic data and clinical parameters were collected, and blood samples were collected in the first minute of the spontaneous ventilation test to evaluate interleukin (IL)-1β, IL-6, IL-8, and IL-10, tumour necrosis factor alpha (TNFα) and C-reactive protein. RESULTS: Patients who experienced extubation failure presented a lower rapid shallow breathing index than those who passed, and these patients also showed a significant increase in C-reactive protein 48 hours after extubation. We observed, moreover, that each unit increase in inflammatory factors led to a higher risk of spontaneous ventilation test failure, with a risk of 2.27 (1.001 - 4.60, p=0.049) for TNFα, 2.23 (1.06 - 6.54, p=0.037) for IL-6, 2.66 (1.06 - 6.70, p=0.037) for IL-8 and 2.08 (1.01 - 4.31, p=0.04) for IL-10, and the rapid shallow breathing index was correlated with IL-1 (r=-0.51, p=0.04). CONCLUSIONS: C-reactive protein is increased in patients who fail the spontaneous ventilation test, and increased ILs are associated with a greater prevalence of failure in this process; the rapid shallow breathing index may not be effective in patients who present systemic inflammation.


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Aged, 80 and over , Ventilator Weaning , Inflammation/blood , Respiratory Function Tests , Stress, Physiological/physiology , C-Reactive Protein/analysis , Cross-Sectional Studies , Prospective Studies , Interleukins/blood , Tumor Necrosis Factor-alpha/blood
10.
An. acad. bras. ciênc ; 89(4): 3015-3029, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-886874

ABSTRACT

ABSTRACT Castor bean is one of the crops with potential to provide raw material for production of oils for biodiesel. This species possess adaptive mechanisms for maintaining the water status when subjected to drought stress. A better understanding these mechanisms under field conditions can unravel the survival strategies used by this species. This study aimed to compare the physiological adaptations of Ricinus communis (L.) in two regions with different climates, the semi-arid and semi-humid subject to water stress. The plants showed greater vapor pressure deficit during the driest hours of the day, which contributed to higher values of the leaf temperature and leaf transpiration, however, the VPD(leaf-air) had the greatest effect on plants in the semi-arid region. In both regions, between 12:00 p.m. and 2:00 p.m., the plants presented reduction in the rates of photosynthesis and intracellular CO2 concentration in response to stomatal closure. During the dry season in the semi-arid region, photoinhibition occurred in the leaves of castor bean between 12:00 p.m. and 2:00 p.m. These results suggest that castor bean plants possess compensatory mechanisms for drought tolerance, such as: higher stomatal control and maintenance of photosynthetic capacity, allowing the plant to survive well in soil with low water availability.


Subject(s)
Photosynthesis/physiology , Ricinus/physiology , Stress, Physiological/physiology , Adaptation, Physiological/physiology , Water , Seasons , Tropical Climate , Plant Transpiration , Desert Climate , Droughts , Humidity
11.
An. acad. bras. ciênc ; 89(4): 3051-3066, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-886847

ABSTRACT

ABSTRACT Water deficit is one of the major stresses affecting plant growth and productivity worldwide. Plants induce various morphological, physiological, biochemical and molecular changes to adapt to the changing environment. Safflower (Carthamus tinctorius L.), a potential oil producer, is highly adaptable to various environmental conditions, such as lack of rainfall and temperatures. The objective of this work was to study the physiological and production characteristics of six safflower lines in response to water deficit followed by rehydration. The experiment was conducted in a protected environment and consisted of 30 days of water deficit followed by 18 days of rehydration. A differential response in terms of photosynthetic pigments, electrolyte leakage, water potential, relative water content, grain yield, oil content, oil yield and water use efficiency was observed in the six lines under water stress. Lines IMA 04, IMA 10, IMA 14 showed physiological characteristics of drought tolerance, with IMA 14 and IMA 16 being the most productive after water deficit. IMA 02 and IMA 21 lines displayed intermediate characteristics of drought tolerance. It was concluded that the lines responded differently to water deficit stress, showing considerable genetic variation and influence to the environment.


Subject(s)
Stress, Physiological/physiology , Water/physiology , Carthamus tinctorius/physiology , Water/metabolism , Principal Component Analysis , Carthamus tinctorius/growth & development , Carthamus tinctorius/metabolism , Droughts , Fluid Therapy
12.
Braz. j. biol ; 77(1): 52-59, Jan-Mar. 2017. tab, graf
Article in English | LILACS | ID: biblio-839168

ABSTRACT

Abstract Some macrophytes species show a high growth potential, colonizing large areas on aquatic environments. Cattail (Typha angustifolia L.) uncontrolled growth causes several problems to human activities and local biodiversity, but this also may lead to competition and further problems for this species itself. Thus, the objective of this study was to investigate anatomical modifications on T. angustifolia plants from different population densities, once it can help to understand its biology. Roots and leaves were collected from natural populations growing under high and low densities. These plant materials were fixed and submitted to usual plant microtechnique procedures. Slides were observed and photographed under light microscopy and images were analyzed in the UTHSCSA-Imagetool software. The experimental design was completely randomized with two treatments and ten replicates, data were submitted to one-way ANOVA and Scott-Knott test at p<0.05. Leaves from low density populations showed higher stomatal density and index. These modifications on stomatal characteristics were more evident on the leaf abaxial surface. Plants from low density populations showed thicker mesophyll and higher proportion of aerenchymal area. Roots from low density populations showed a higher proportion of the vascular cylinder. Whereas, plants from higher density populations showed greater thickness of the endodermis, exodermis, phloem and root cortex. Higher density populations showed a higher proportion of aerenchymal gaps in the root cortex. Therefore, cattail plants from populations growing under high density population show anatomical traits typical of plants under stress, which promotes the development of less functional anatomical modifications to aquatic environments.


Resumo Algumas espécies de macrófitas podem apresentar um elevado potencial de crescimento, colonizando extensas áreas de ambientes aquáticos. O crescimento descontrolado da taboa (Typha angustifolia L.) causa problemas para a biodiversidade local e para atividades antrópicas, isso também pode levar à competição e problemas para a própria espécie. Dessa forma, o objetivo desse trabalho foi verificar se ocorrem modificações anatômicas em plantas de Typha angustifolia L. de diferentes densidades populacionais, uma vez que essas podem auxiliar na compreensão da biologia dessa espécie. Raízes e folhas de T. angustifolia foram coletadas de populações naturais com alto e baixo adensamento populacional. Esse material vegetal foi fixado e submetido a procedimentos usuais de microtécnica vegetal. As lâminas foram observadas e fotografadas em microscopia de luz e as imagens analisadas no software UTHSCSA-Imagetool. O delineamento experimental foi inteiramente casualizado com dois tratamentos e dez repetições, os dados foram submetidos à análise de variância e ao teste de Scott-Knott para p<0,05. As folhas das populações com baixa densidade demonstraram maior densidade e índice estomáticos. Essas características foram mais evidentes na superfície abaxial em comparação com a superfície adaxial. As plantas de populações com baixo adensamento demonstraram maior espessura do mesofilo e área de aerênquima foliar. As raízes das populações com baixo adensamento demonstraram maior proporção do cilindro vascular. Por outro lado, as plantas de populações com alto adensamento demonstraram maior espessura da endoderme, exoderme, floema e do córtex nas raízes. Populações de alto adensamento demonstraram maior proporção de aerênquima no córtex radicular. Portanto, plantas de taboa sob alto adensamento populacional estão sob estresse o qual promove o desenvolvimento de modificações anatômicas menos funcionais para os ambientes aquáticos.


Subject(s)
Stress, Physiological/physiology , Typhaceae/anatomy & histology , Adaptation, Physiological/physiology , Random Allocation , Analysis of Variance , Population Density , Plant Roots/anatomy & histology , Plant Leaves/growth & development , Typhaceae/physiology , Biodiversity , Aquatic Organisms/physiology
13.
Rev. bras. anestesiol ; 67(1): 28-34, Jan.-Feb. 2017. tab, graf
Article in English | LILACS | ID: biblio-843354

ABSTRACT

Abstract Objective: General anesthesia causes reduction of functional residual capacity. And this decrease can lead to atelectasis and intrapulmonary shunting in the lung. In this study we want to evaluate the effects of 5 and 10 cmH2O PEEP levels on gas exchange, hemodynamic, respiratory mechanics and systemic stress response in laparoscopic cholecystectomy. Methods: American Society of Anesthesiologist I-II physical status 43 patients scheduled for laparoscopic cholecystectomy were randomly selected to receive external PEEP of 5 cmH2O (PEEP 5 group) or 10 cmH2O PEEP (PEEP 10 group) during pneumoperitoneum. Basal hemodynamic parameters were recorded, and arterial blood gases (ABG) and blood sampling were done for cortisol, insulin and glucose level estimations to assess the systemic stress response before induction of anesthesia. Thirty minutes after the pneumoperitoneum, the respiratory and hemodynamic parameters were recorded again and ABG and sampling for cortisol, insulin, and glucose levels were repeated. Lastly hemodynamic parameters were recorded; ABG analysis and sampling for stress response levels were taken after 60 minutes from extubation. Results: There were no statistical differences between the two groups about hemodynamic and respiratory parameters except mean airway pressure (P mean). P mean, compliance and PaO2; pH values were higher in 'PEEP 10 group'. Also, PaCO2 values were lower in 'PEEP 10 group'. No differences were observed between insulin and lactic acid levels in the two groups. But postoperative cortisol level was significantly lower in 'PEEP 10 group'. Conclusion: Ventilation with 10 cmH2O PEEP increases compliance and oxygenation, does not cause hemodynamic and respiratory complications and reduces the postoperative stress response.


Resumo Objetivo: A anestesia geral causa a redução da capacidade residual funcional e essa diminuição pode levar à atelectasia pulmonar e ao shunt intrapulmonar. Neste estudo pretendemos avaliar os efeitos de níveis de 5 e 10 cmH2O de pressão expiratória final positiva (PEEP) sobre as trocas gasosas, a hemodinâmica, a mecânica respiratória e a resposta ao estresse sistêmico em colecistectomia laparoscópica. Método: Foram selecionados aleatoriamente 43 pacientes, estado físico ASA I-II, agendados para colecistectomia laparoscópica, para receber PEEP a 5 cmH2O (grupo PEEP-5) ou PEEP de 10 cmH2O (grupo PEEP-10) durante o pneumoperitônio. Os parâmetros hemodinâmicos foram registrados, gasometria arterial e coleta de sangue foram feitas para estimativa dos níveis de cortisol, insulina e glicose para avaliar a resposta ao estresse sistêmico antes da indução anestésica. Trinta minutos após o pneumoperitônio, os parâmetros hemodinâmicos e respiratórios foram registrados novamente e gasometria e amostragem para os níveis de cortisol, insulina e glicose foram repetidos. E os últimos parâmetros hemodinâmicos foram registrados, análise e amostragem de gasometria para os níveis de resposta ao estresse foram feitas após 60 minutos da extubação. Resultados: Não houve diferença estatística entre dois grupos quanto aos parâmetros hemodinâmicos e respiratórios, exceto pressão média das vias aéreas (Pmédia). Os valores de Pmédia, complacência, PaO2 e do pH foram maiores no grupo PEEP-10. Também os valores de PaCO2 foram menores no grupo PEEP-10. Não foram observadas quaisquer diferenças entre os níveis de insulina e de ácido láctico nos dois grupos. Porém, o nível de cortisol no pós-operatório foi significativamente menor no grupo PEEP-10. Conclusão: Ventilação com PEEP de 10 cmH2O aumenta a complacência e a oxigenação, não causa hemodinâmica e complicações respiratórias e reduz a resposta ao estresse no pós-operatório.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Aged , Young Adult , Stress, Physiological/physiology , Respiratory Mechanics/physiology , Cholecystectomy, Laparoscopic , Hemodynamics/physiology , Blood Pressure/physiology , Prospective Studies , Positive-Pressure Respiration , Electrocardiography , Heart Rate/physiology , Middle Aged
14.
Rev. argent. microbiol ; 48(4): 347-357, dic. 2016. ilus, graf, tab
Article in Spanish | LILACS | ID: biblio-1041772

ABSTRACT

El hongo Macrophomina phaseolina (Tassi) Goid., agente causal de la enfermedad denominada «pudrición carbonosa¼, provoca pérdidas significativas en la producción de cultivos como maíz, sorgo, soya y frijol en México. Este hongo, parásito facultativo, muestra amplia capacidad de adaptación a ambientes estresantes, donde existen altas temperaturas y deficiencia hídrica, condiciones frecuentes en gran parte de la agricultura de dicho país. En este trabajo se describen algunos aspectos básicos de la etiología y la epidemiología de M. phaseolina. Asimismo, se revisa la importancia que guardan las respuestas de este hongo a ambientes estresantes, particularmente la deficiencia hídrica, de acuerdo con caracteres morfológicos y del crecimiento, así como fisiológicos, bioquímicos y de patogenicidad. Finalmente, se presentan algunas perspectivas de estudio del género, que enfatizan la necesidad de mejorar su conocimiento, con base en la aplicación de herramientas tradicionales y de biotecnología, y de dilucidar mecanismos de tolerancia al estrés ambiental, extrapolables a otros microorganismos útiles al hombre.


Fungus Macrophomina phaseolina (Tassi) Goid. is the causative agent of charcoal rot disease which causes significant yield losses in major crops such as maize, sorghum, soybean and common beans in Mexico. This fungus is a facultative parasite which shows broad ability to adapt itself to stressed environments where water deficits and/or high temperature stresses commonly occur. These environmental conditions are common for most cultivable lands throughout Mexico. Here we describe some basic facts related to the etiology and epidemiology of the fungus as well as to the importance of responses to stressed environments, particularly to water deficits, based on morphology and growth traits, as well as on physiology, biochemistry and pathogenicity of fungus M. phaseolina. To conclude, we show some perspectives related to future research into the genus, which emphasize the increasing need to improve the knowledge based on the application of both traditional and biotechnological tools in order to elucidate the mechanisms of resistance to environmental stress which can be extrapolated to other useful organisms to man.


Subject(s)
Adaptation , Environment , Crop Production/economics , Fungi/growth & development , Fungi/physiology , Fungi/pathogenicity , Stress, Physiological/physiology
15.
ImplantNewsPerio ; 1(3): 571-576, abr.-mai. 2016. tab
Article in Portuguese | LILACS, BBO | ID: biblio-847622

ABSTRACT

O objetivo deste trabalho foi verificar na literatura possíveis interações entre doença periodontal, patologia de caráter infeccioso e altamente prevalente na população adulta brasileira, e o cortisol salivar através de uma revisão da literatura. Foram pesquisados artigos científicos nas bases de dados Scielo e PubMed, a partir do ano de 2002. Foram excluídos artigos científicos sobre pesquisas experimentais e que não estivessem redigidos em português ou inglês. Através da revisão da literatura, foi possível aclarar as relações entre estresse, cortisol e doença periodontal, que parecem ocorrer através da ativação do eixo hipotálamo-pituitária adrenal e pela ativação do sistema nervoso autônomo. Isto gera alterações no padrão imunológico do paciente, pela liberação e ativação de catecolaminas, citocinas e outros mediadores da inflamação, fazendo com que o paciente se torne mais suscetível à doença periodontal. Além disto, também foi verificado que o cortisol, dependendo de sua concentração, pode favorecer o crescimento de patógenos periodontais. Finalmente, a maioria dos trabalhos avaliados revela uma correlação positiva entre estresse e doença periodontal, que pode ser útil na avaliação clínica destes pacientes. Porém, ainda faltam estudos longitudinais para aumentar a evidência científica clínica e alinhar a metodologia das pesquisas nesta área.


The aim of this study was to assess in the literature possible interactions between periodontal disease, an infectious pathology and highly prevalent in the adult Brazilian population, and salivary cortisol, through a literature review. Scientific articles were searched in PubMed and Scielo databases from 2002 to 2015. Papers on experimental research and not written in the English language were excluded. It was possible to clarify the relationship between stress, cortisol and periodontal disease, which seem to occur through activation of the hypothalamic-pituitary-adrenal axis and the activation of the autonomic-nervous system. This leads to changes in the patient's immune system, by release and activation of catecholamine, cytokines and other infl ammation mediators, making the patient more susceptible to periodontal disease. In addition, it was also found that cortisol, depending on its concentration, may upregulate the growth of periodontal pathogens. Finally, most of the evaluated studies showed a positive correlation between stress and periodontal disease, which can be useful in the clinical evaluation of these patients. However, longitudinal studies are lacking to increase the clinical scientific evidence and align the research methods in this area.


Subject(s)
Humans , Hydrocortisone/analysis , Hydrocortisone/metabolism , Periodontal Diseases , Saliva/chemistry , Stress, Physiological/physiology
16.
Biol. Res ; 49: 1-10, 2016. ilus, graf
Article in English | LILACS | ID: biblio-950843

ABSTRACT

Schizophrenia is a severe psychiatric disorder that results in a significant disability for the patient. The disorder is characterized by impairment of the adaptive orchestration of actions, a cognitive function that is mainly dependent on the prefrontal cortex. This behavioral deficit, together with cellular and neurophysiological alterations in the prefrontal cortex, as well as reduced density of GABAergic cells and aberrant oscillatory activity, all indicate structural and functional deficits of the prefrontal cortex in schizophrenia. Among the several risk factors for the development of schizophrenia, stress during the prenatal period has been identified as crucial. Thus, it is proposed that prenatal stress induces neurodevelopmental alterations in the prefrontal cortex that are expressed as cognitive impairment observed in schizophrenia. However, the precise mechanisms that link prenatal stress with the impairment of prefrontal cortex function is largely unknown. Reelin is an extracellular matrix protein involved in the development of cortical neural connectivity at embryonic stages, and in synaptic plasticity at postnatal stages. Interestingly, down-regulation of reelin expression has been associated with epigenetic changes in the reelin gene of the prefrontal cortex of schizophrenic patients. We recently showed that, similar to schizophrenic patients, prenatal stress induces down-expression of reelin associated with the methylation of its promoter in the rodent prefrontal cortex. These alterations were paralleled with altered prefrontal cortex functional connectivity and impairment in prefrontal cortex-dependent behavioral tasks. Therefore, considering molecular, cellular, physiological and behavioral evidence, we propose a unifying framework that links prenatal stress and prefrontal malfunction through epigenetic alterations of the reelin gene.


Subject(s)
Humans , Female , Pregnancy , Prenatal Exposure Delayed Effects/physiopathology , Schizophrenia/etiology , Schizophrenia/physiopathology , Stress, Physiological/physiology , Brain/embryology , Serine Endopeptidases/genetics , Cell Adhesion Molecules, Neuronal/genetics , Extracellular Matrix Proteins/genetics , Epigenesis, Genetic/physiology , Nerve Tissue Proteins/genetics , Social Behavior Disorders/physiopathology , Brain/physiopathology , Gene Expression , Risk Factors , Cognition Disorders/physiopathology , DNA Methylation
17.
Pesqui. vet. bras ; 35(10): 859-862, out. 2015. graf
Article in English | LILACS | ID: lil-767752

ABSTRACT

Blood samples collection is a common method in biological research using domestic animals. However, most blood sampling techniques are complicated and highly invasive and may therefore not be appropriate for wildlife animals in research concerning stress. Thus, a non-invasive method to measure steroid hormones is critically needed. The first goal of this study was to determine how glucocorticoids concentrations are impacted by translocation and reproductive activity in crab-eating-fox (Cerdocyoun thous) in captivity. The physiological relevance of fecal glucocorticoid metabolites was further validated by demonstrating: (1) The translocation of a male to a females enclosure resulted in a 3.5-fold increase compared to baseline concentrations, (2) changes in adrenocortical activity, as reflected in concentrations of fecal cortisol metabolites during reproduction, gestation and lactation in females foxes, indicating that social interactions resulted in large increases of fecal glucocorticoids metabolites during the reproductive season. From these findings we conclude that fecal samples can be used for the non-invasive assessment of adrenocortical status in crab-eating-fox...


Coleta de sangue é um método comumente utilizado na pesquisa com animais domésticos. Entretanto, a técnica de coleta de sangue torna-se complicada e altamente invasiva em animais selvagens devido ao estresse, tornando-a inapropriada para pesquisa. Dessa maneira, métodos não invasivos utilizados na mensuração de hormonios tornam-se necessários. O principal objetivo deste estudo foi determinar como as concentrações de glucocorticoides atuam durante a translocação e a atividade reprodutiva de cachorro-do-mato (Cerdocyoun thous) em cativeiro. A relevância fisiológica da análise de metabolitos fecais de glucocorticoides pôde ser validada pela demonstração de que: (1) A translocação de machos para o recinto de fêmeas resultou em um aumento de 3.5 vezes comparado a concentrações basais; (2) mudanças na atividade adrenocortical, como reflexo das concentrações de metabolitos de cortisol fecal durante a reprodução, gestação e lactação em femeas de cachorro-do-mato (Cerdocyoun thous), indicaram que interações sociais resultaram em aumento de glucocorticoides fecais durante a época reprodutiva. Com estas constatações podemos concluir que amostras fecais podem ser usadas para acesso não invasivo da atividade adrenocortical em cachorro-do-mato (Cerdocyoun thous)...


Subject(s)
Animals , Stress, Physiological/physiology , Feces/chemistry , Glucocorticoids/metabolism , Hydrocortisone/metabolism , Foxes/physiology , Animals, Wild/physiology , Reproduction/physiology , Diagnostic Techniques and Procedures/veterinary
18.
Arq. bras. med. vet. zootec ; 67(3): 747-754, May-Jun/2015. graf
Article in Portuguese | LILACS | ID: lil-753919

ABSTRACT

As lesões coronarianas já foram relatadas em espécies de peixes anádromos, com características semelhantes às observadas em aterosclerose humana, mas não em peixes cultivados sem interferência de padrões reprodutivos. Objetivou-se descrever lesões coronarianas em beijupirá (Rachycentron canadum) criado em sistema offshore, em 54 exemplares coletados ao longo do cultivo de oito meses. Amostras de tecido cardíaco de alevinos e juvenis foram submetidas à análise histopatológica e à microscopia eletrônica de transmissão (MET), para visualização de lesões coronarianas, sendo as lâminas histológicas coradas pela técnica de hematoxilina-eosina, ácido periódico de Schiff, alcian blue e reticulina de Gomori. Exames realizados pela fotomicroscopia de luz evidenciaram lesões arteriais caracterizadas por hiperplasia das túnicas íntima e média de artérias coronárias em, respectivamente, 29,63% e 79,63% dos animais, com redução do lúmen arterial. Na MET, foram observadas alterações na estrutura das coronárias com espessamento do endotélio e membrana basal, proliferação de fibroblastos e fibras colágenas, com acúmulo de material lipídico subendotelial, resíduos celulares aderidos à membrana basal e vesículas pinocitóticas com presença de lisossomos isolados. Constatou-se que os peixes da espécie Rachycentron canadum criados em cativeiro desenvolvem lesão arterial do tipo crônica degenerativa inflamatória.


The coronary lesions have been reported in species of anadromous fish with similar characteristics as those observed in human atherosclerosis, but not in farmed fish without interference of reproductive patterns. This study aimed to describe coronary lesions in beijupirá (Rachycentron canadum) farmed in an offshore system, in 54 specimens collected along an eight month cultivation period. Samples of heart tissue of fry and juveniles were subjected to histopathological analysis and transmission electron microscopy (TEM) for visualization of coronary lesions, the histology slides were stained using hematoxylin-eosin, periodic acid Schiffh, alcian blue, and reticulin of Gomori. Examinations performed by light microscopy showed arterial lesions characterized by hyperplasia of the intima and media tunics, respectively in 29.63% and 79.63 % of the animals, with reduced lumen. In TEM changes in the structure of the coronary endothelium and thickening of the basement membrane, proliferation of fibroblasts and collagen fibers, with subendothelial accumulation of lipid material, cellular debris adhering to the basement membrane and presence of pinocytotics vesicles and isolated lysosomes were observed. It has been found that the Rachycentron canadum fish species farmed in captivity develop arterial lesion of the chronic inflammatory degenerative type.


Subject(s)
Animals , Coronary Artery Disease/veterinary , Perciformes , Tunica Intima/pathology , Tunica Media/pathology , Stress, Physiological/physiology , Microscopy, Electron, Transmission/veterinary , Histological Techniques/veterinary , Coronary Vessels/pathology
19.
Arq. bras. med. vet. zootec ; 67(3): 837-845, May-Jun/2015. tab, graf
Article in Portuguese | LILACS | ID: lil-753933

ABSTRACT

Objetivou-se com este trabalho estimar o bem-estar de suínos a partir de registros de sua vocalização, durante alojamento em granja comercial. Foram utilizados 150 suínos machos castrados, distribuídos aleatoriamente em cinco baias. Os suínos foram submetidos a diferentes situações de estresse: sede (sem acesso a água), fome (sem acesso ao alimento), estresse térmico (Índice de temperatura e umidade - ITU >74). Para o tratamento controle, os animais foram mantidos em situação de conforto, com acesso a alimento e água, e ambiente com ITU <70. Foram registrados os sinais acústicos a cada 30 minutos, durante período ininterrupto de três horas, totalizando seis coletas para cada situação de estresse. Os sinais foram digitalizados a uma frequência de até 44.100Hz, por um período de 3 minutos. Posteriormente, os áudios foram analisados pelo software Praat(r) 5.1.19. Os atributos gerados a partir desse software foram a energia do sinal (Pa²*s), amplitude máxima e amplitude mínima (Pa), a frequência de picht (Hz), a intensidade sonora (dB) e quatro níveis de formantes (F1; F2; F3 e F4), também chamados de harmônicas (Hz). Verificou-se que, dependendo do estímulo estressor e de sua duração, os atributos acústicos energia e intensidade do sinal, frequência de pitch e as formantes 2 e 4 apresentaram diferenciação. Os atributos sonoros da vocalização de suínos variam de maneira distinta em função do tipo e duração do estímulo estressante, funcionando, quando associados, como ferramenta eficiente para quantificar o grau de estresse dos animais.


This work aimed to estimate the welfare of pigs using their vocalization records during rearing in a commercial swine farm. A total of 150 barrow pigs were randomly distributed into five pens. Pigs were exposed to different stressful situations: Thirst (no access to water), hunger (no access to the food), thermal stress (Temperature and Humidity Index - THI >74). For the control treatment, the animals were kept in a situation of comfort, with full access to food and water, and environment THI <70. Acoustic signals were recorded every 30 minutes during a continuous period of three hours, totaling six samples for each stress exposure. The signals were digitized at a frequency of up to 44,100 Hz, for a period of 3 minutes. Later the audios were analyzed using the Praat (r) 5.1.19 software. The attributes generated from this software were the signal energy (Pa² * s), the maximum amplitude and the minimum amplitude (Pa), the frequency of pitch (Hz), the sound intensity (dB) and four levels of formants (F1, F2, F3 and F4), also called harmonics (Hz). It was found that depending on the acoustic attributes, the stressor stimuli and its duration indicate energy and signal strength, frequency of pitch and formants 2 and 4 showed differentiation. The sound attributes of the pig vocalization varied in different ways depending on the type and duration of the stressful exposure, functioning as an efficient tool to quantify the degree of animal degree.


Subject(s)
Animals , Male , Animal Welfare , Stress, Physiological/physiology , Swine/metabolism , Vocalization, Animal/classification , Heat Stress Disorders/veterinary
20.
Nutrire Rev. Soc. Bras. Aliment. Nutr ; 40(2): 145-152, 2015. tab
Article in Portuguese | LILACS | ID: biblio-881939

ABSTRACT

Exposure to stress and undernutrition alone are important risk factors in the development of neurobehavioral disorders. However, few studies focus on how chronic postnatal stress affects adaptive behavioral response to undernutrition in utero. OBJECTIVE: to investigate whether chronic postnatal stress exposure constitutes a risk factor in addition to undernutrition in utero to developing neurobehavioral disorders in young rats. METHODS: we evaluated the overall activity in the Open Field, and anxiety in the Elevated Plus Maze of male Wistar rats (35 days) from dams submitted or not to food restriction (50%) throughout pregnancy and exposed or not to restraint stress (single sections 1 h/day, 5 days/week for 2 weeks from weaning). RESULTS: postnatal stress and undernutrition in utero, alone and in combination, did not cause changes to the young rats behavior, except for a decrease of locomotion in the central and middle zone of the Open Field in the offsprings subjected to undernutrition in utero. The postnatal stress, alone and in combination, did not change the activity in Elevated Plus Maze. However, the time spent in the open arms decreased while the time in the closed arms increased in undernourished rats in utero. The anxiety index was decreased by undernutrition in utero. CONCLUSION: the absence of behavioral changes in young rats exposed to undernutrition in utero in association with chronic postnatal stress suggests that the physiological changes that lead to anxiogenic condition induced by undernutrition in utero alone take place mainly during the postnatal development


Exposição ao estresse e desnutrição, isoladamente, são importantes fatores de risco no desenvolvimento de transtornos neurocomportamentais. Entretanto, poucos estudos focam como o estresse pós-natal crônico afeta a resposta comportamental adaptativa à desnutrição in utero. OBJETIVO: investigar se a exposição pós-natal crônica ao estresse constitui-se em fator de risco adicional à desnutrição in utero para o desenvolvimento de transtornos neurocomportamentais em ratos jovens. MÉTODOS: avaliou-se a atividade geral, em Campo Aberto, e a ansiedade, no Labirinto em Cruz Elevado, de ratos machos Wistar (35 dias) provenientes de ratas submetidas ou não à restrição alimentar (50%) durante toda a prenhez, e expostos ou não ao estresse de contenção (seções únicas 1 h/dia, 5 dias/semana, durante 2 semanas a partir do desmame). RESULTADOS: o estresse pós-natal e a desnutrição in utero, isoladamente e em associação, não determinaram alterações no comportamento de ratos jovens, exceto pela diminuição da locomoção na zona central e mediana do Campo Aberto em proles submetidas à desnutrição in utero. O estresse pós-natal, isoladamente e em associação, não alterou a atividade no Labirinto em Cruz Elevado. Entretanto, o tempo de permanência nos braços abertos diminuiu enquanto o tempo nos braços fechados aumentou em ratos desnutridos in utero. O índice de ansiedade foi diminuído pela desnutrição in utero. CONCLUSÃO: a ausência de alterações comportamentais em ratos jovens expostos à desnutrição in utero em associação ao estresse pós-natal crônico sugere que as alterações fisiológicas que levam à condição ansiogênica induzida pela desnutrição in utero, isoladamente, têm lugar principalmente durante o desenvolvimento pós-natal


Subject(s)
Animals , Rats , Anxiety Disorders , Behavior, Animal , Fetal Nutrition Disorders , Stress, Physiological/physiology
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