The role of superoxide dismutase in the susceptibility of bean leaves to ozone injury

1984 ◽  
Vol 62 (2) ◽  
pp. 236-240 ◽  
Author(s):  
C. P. Chanway ◽  
V. C. Runeckles
Keyword(s):  
Superoxide Dismutase ◽  
Ozone Exposure ◽  
Acute Injury ◽  
Ozone Injury ◽  
Stomatal Behaviour ◽  
Bean Plants ◽  
Ozone Pretreatment ◽  
Low Levels ◽  
Pass Through

The primary leaves of bush bean plants pretreated daily with very low levels of ozone (0.02 or 0.05 ppm) pass through stages of varying susceptibility to a subsequent acute dose. This variation in response can only partly be accounted for by stomatal behaviour. Present studies indicate that the levels of the oxyradical scavenger, superoxide dismutase (SOD), assayed in leaf homogenates, appear to play no role in the phenomenon. No observed changes in the levels of extracted SOD following various low ozone pretreatment regimes could be related to changes in susceptibility to acute injury, in comparisons with control plants maintained in charcoal-filtered air prior to acute fumigation. The only significant increases in SOD levels which appeared to be directly related to ozone exposure occurred simultaneously with the appearance of visible symptoms of injury from either the cumulative chronic or acute ozone exposures.

Effects of ambient ozone pretreatment on transpiration and susceptibility to ozone injury

1977 ◽  
Vol 55 (2) ◽  
pp. 193-197 ◽  
Author(s):  
V. C. Runeckles ◽  
P. M. Rosen
Keyword(s):  
Acute Injury ◽  
Relative Susceptibility ◽  
Ambient Ozone ◽  
Ozone Injury ◽  
Early Increase ◽  
Initial Decrease ◽  
Ozone Pretreatment ◽  
Low Levels ◽  
Ozone Levels ◽  
Bean Leaves

The effects of daily pretreatment with low levels of ozone (0.02 μl litre−1) on the susceptibility of primary bean leaves to acute ozone injury involve several stages. Plants subjected daily to low ozone from the time of sowing exhibit an early resistance to acute injury which decreases with time. When the low ozone pretreatments begin about 10 days after sowing, there is no change in susceptibility for 2–3 days, then it increases to a level which remains constant. At the start of this period of greater susceptibility, such pretreated plants are more susceptible than controls in filtered air; after about 8 days, they are less susceptible because of the marked increase insusceptibility of the controls with time. In contrast, daily pretreatments with higher (0.05 μl litre−1) levels, beginning 8 days after sowing, cause an initial decrease in susceptibility followed by a marked increase, leading to predisposition to acute injury.The early increase in susceptibility of plants transferred from filtered air to 0.02 μl ozone litre−1appears to be the result of the decreased ability of stomates to close in response to high ozone levels. The later stage of decreased relative susceptibility is associated with a dampening of stomatal activity, which is independent of the presence of high ozone levels.

Social Motives Predict Loneliness During a Developmental Transition

2017 ◽  
Vol 76 (4) ◽  
pp. 145-153 ◽  
Author(s):  
Jana Nikitin ◽  
Alexandra M. Freund
Keyword(s):  
Social Relationships ◽  
Well Being ◽  
Social Avoidance ◽  
Social Approach ◽  
Social Motives ◽  
Developmental Transitions ◽  
Avoidance Motivation ◽  
Negative Effect ◽  
Low Levels

Abstract. Establishing new social relationships is important for mastering developmental transitions in young adulthood. In a 2-year longitudinal study with four measurement occasions (T1: n = 245, T2: n = 96, T3: n = 103, T4: n = 85), we investigated the role of social motives in college students’ mastery of the transition of moving out of the parental home, using loneliness as an indicator of poor adjustment to the transition. Students with strong social approach motivation reported stable and low levels of loneliness. In contrast, students with strong social avoidance motivation reported high levels of loneliness. However, this effect dissipated relatively quickly as most of the young adults adapted to the transition over a period of several weeks. The present study also provides evidence for an interaction between social approach and social avoidance motives: Social approach motives buffered the negative effect on social well-being of social avoidance motives. These results illustrate the importance of social approach and social avoidance motives and their interplay during developmental transitions.

Social and Temporal Comparisons as Moderators of Psychological Resources Associations With Wellbeing

2016 ◽  
Vol 37 (2) ◽  
pp. 96-104 ◽  
Author(s):  
Hasida Ben-Zur
Keyword(s):  
Life Satisfaction ◽  
Positive Affect ◽  
Subjective Wellbeing ◽  
Social Comparisons ◽  
Self Esteem ◽  
Psychological Resources ◽  
Low Levels ◽  
Age Range ◽  
General Wellbeing

Abstract. The current study investigated the associations of psychological resources, social comparisons, and temporal comparisons with general wellbeing. The sample included 142 community participants (47.9% men; age range 23–83 years), who compared themselves with others, and with their younger selves, on eight dimensions (e.g., physical health, resilience). They also completed questionnaires assessing psychological resources of mastery and self-esteem, and three components of subjective wellbeing: life satisfaction and negative and positive affect. The main results showed that high levels of psychological resources contributed to wellbeing, with self-enhancing social and temporal comparisons moderating the effects of resources on certain wellbeing components. Specifically, under low levels of mastery or self-esteem self-enhancing social or temporal comparisons were related to either higher life satisfaction or positive affect. The results highlight the role of resources and comparisons in promoting people’s wellbeing, and suggest that self-enhancing comparisons function as cognitive coping mechanisms when psychological resources are low.

Ups and downs on the roller coaster of task conflict: the role of group cognitive complexity, collective emotional intelligence and team creativity

2020 ◽  
Vol 18 (1) ◽  
pp. 23-37
Author(s):  
Andreea Gheorghe ◽  
Oana Fodor ◽  
Anișoara Pavelea
Keyword(s):  
Emotional Intelligence ◽  
Cognitive Complexity ◽  
Empirical Support ◽  
Task Conflict ◽  
Team Creativity ◽  
Mediating Role ◽  
Low Levels ◽  
Explanatory Mechanism ◽  
The Relationship

This study explores the association between task conflict and team creativity and the role of group cognitive complexity (GCC) as a potential explanatory mechanism in a sample of 159 students organized in 49 groups. Moreover, we analyzed the moderating effect of collective emotional intelligence (CEI)in the relationship between task conflict and GCC.As hypothesized, we found that task conflict has a nonlinear relationship with GCC, but contrary to our expectations, it follows a U-shaped association, not an inversed U-shape. In addition,the moderating role of CEI was significant only at low levels. Contrary to our expectation, the mediating role of GCC did not receive empirical support. Theoretical and practical contributions are discussed.

scholarly journals Parental Warmth, Gratitude, and Prosocial Behavior among Chinese Adolescents: The Moderating Effect of School Climate

2021 ◽  
Vol 18 (13) ◽  
pp. 7033
Author(s):  
Haocheng Luo ◽  
Qingqi Liu ◽  
Chengfu Yu ◽  
Yangang Nie
Keyword(s):  
School Climate ◽  
Prosocial Behavior ◽  
Longitudinal Design ◽  
Positive Association ◽  
Theoretical Explanation ◽  
Parental Warmth ◽  
Physical And Mental Health ◽  
Low Levels ◽  
Moderating Role

Parental warmth plays an important role in the development of adolescents’ physical and mental health. There are numerous empirical studies indicating a relationship between parental warmth and prosocial behavior among adolescents, although the underlying mechanisms of this association remain unclear. Adopting a longitudinal design across two time points, the present study proposes a moderated mediation model to explore the mediating role of gratitude and the moderating role of the school climate between parental warmth and prosocial behavior. The sample consisted of 943 participants (483 boys and 451 girls) who participated in the second assessment and completed questionnaires assessing gratitude, school climate, and prosocial behavior in April 2019. Their parents participated in the first assessment and completed a questionnaire pertaining to parental warmth in October 2018. After controlling for the gender and age of the adolescents, the results showed that the positive association between parental warmth and prosocial behavior is mediated by gratitude, and school climate does play a moderating role in the second half of the mediating path. Specifically, the school climate can play a protective role in adolescents with low levels of gratitude. For adolescents with less gratitude, a strong school climate can promote more prosocial behaviors and can effectively alleviate the negative prediction of low levels of gratitude. This study provides a theoretical explanation for the generation of adolescents’ prosocial behavior and provides theoretical guidance for the interventions of schools and parents.

scholarly journals Low level of plasminogen increases risk for mortality in COVID-19 patients

2021 ◽  
Vol 12 (8) ◽  
Author(s):  
David Della-Morte ◽  
Francesca Pacifici ◽  
Camillo Ricordi ◽  
Renato Massoud ◽  
Valentina Rovella ◽  
...  
Keyword(s):  
Fasting Blood Glucose ◽  
Multidimensional Analysis ◽  
Strongly Correlated ◽  
Analysis Model ◽  
Inflammatory Parameters ◽  
Number Of Patients ◽  
Caucasian Patients ◽  
Low Levels ◽  
Organ Dysfunctions

AbstractThe pathophysiology of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and especially of its complications is still not fully understood. In fact, a very high number of patients with COVID-19 die because of thromboembolic causes. A role of plasminogen, as precursor of fibrinolysis, has been hypothesized. In this study, we aimed to investigate the association between plasminogen levels and COVID-19-related outcomes in a population of 55 infected Caucasian patients (mean age: 69.8 ± 14.3, 41.8% female). Low levels of plasminogen were significantly associated with inflammatory markers (CRP, PCT, and IL-6), markers of coagulation (D-dimer, INR, and APTT), and markers of organ dysfunctions (high fasting blood glucose and decrease in the glomerular filtration rate). A multidimensional analysis model, including the correlation of the expression of coagulation with inflammatory parameters, indicated that plasminogen tended to cluster together with IL-6, hence suggesting a common pathway of activation during disease’s complication. Moreover, low levels of plasminogen strongly correlated with mortality in COVID-19 patients even after multiple adjustments for presence of confounding. These data suggest that plasminogen may play a pivotal role in controlling the complex mechanisms beyond the COVID-19 complications, and may be useful both as biomarker for prognosis and for therapeutic target against this extremely aggressive infection.

scholarly journals Platelet and Erythrocyte Extravasation across Inflamed Corneal Venules Depend on CD18, Neutrophils and Mast Cell Degranulation

2021 ◽  
Vol 22 (14) ◽  
pp. 7360
Author(s):  
Angie De La Cruz ◽  
Aubrey Hargrave ◽  
Sri Magadi ◽  
Justin A. Courson ◽  
Paul T. Landry ◽  
...  
Keyword(s):  
Mast Cell ◽  
Cell Types ◽  
Mast Cell Degranulation ◽  
Wild Type ◽  
Delayed Wound Healing ◽  
Corneal Epithelial ◽  
Corneal Abrasion ◽  
Low Levels ◽  
Endothelial Pores

Platelet extravasation during inflammation is under-appreciated. In wild-type (WT) mice, a central corneal epithelial abrasion initiates neutrophil (PMN) and platelet extravasation from peripheral limbal venules. The same injury in mice expressing low levels of the β2-integrin, CD18 (CD18hypo mice) shows reduced platelet extravasation with PMN extravasation apparently unaffected. To better define the role of CD18 on platelet extravasation, we focused on two relevant cell types expressing CD18: PMNs and mast cells. Following corneal abrasion in WT mice, we observed not only extravasated PMNs and platelets but also extravasated erythrocytes (RBCs). Ultrastructural observations of engorged limbal venules showed platelets and RBCs passing through endothelial pores. In contrast, injured CD18hypo mice showed significantly less venule engorgement and markedly reduced platelet and RBC extravasation; mast cell degranulation was also reduced compared to WT mice. Corneal abrasion in mast cell-deficient (KitW-sh/W-sh) mice showed less venule engorgement, delayed PMN extravasation, reduced platelet and RBC extravasation and delayed wound healing compared to WT mice. Finally, antibody-induced depletion of circulating PMNs prior to corneal abrasion reduced mast cell degranulation, venule engorgement, and extravasation of PMNs, platelets, and RBCs. In summary, in the injured cornea, platelet and RBC extravasation depends on CD18, PMNs, and mast cell degranulation.

scholarly journals Role of superoxide dismutase in the fallopian tube function: Immunohistochemical assessment of superoxide dismutase in the fallopian tube.

1991 ◽  
Vol 24 (1) ◽  
pp. 85-91 ◽  
Author(s):  
KATSUHIKO NARIMOTO ◽  
YOICHI NODA ◽  
MASAHIDE SHIOTANI ◽  
SATOSHI NATSUYAMA ◽  
TAKAHIDE MORI ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Fallopian Tube ◽  
Tube Function ◽  
Immunohistochemical Assessment
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