The freeze-avoidance response of smelt Osmerus mordax

2002 ◽  
Vol 205 (10) ◽  
pp. 1419-1427 ◽  
Author(s):  
Jason R. Treberg ◽  
Connie E. Wilson ◽  
Robert C. Richards ◽  
K. Vanya Ewart ◽  
William R. Driedzic
Keyword(s):  
Avoidance Response ◽  
Liver Enzymes ◽  
Thermal Hysteresis ◽  
Early Spring ◽  
Osmerus Mordax ◽  
Mrna Levels ◽  
Ambient Conditions ◽  
Freeze Avoidance ◽  
Urea Content ◽  
Trimethylamine Oxide

SUMMARY Smelt (Osmerus mordax) were maintained at either ambient water temperature or approximately 5°C and various aspects of their freeze-avoidance response were examined from early winter until early spring. Plasma levels of glycerol, trimethylamine oxide (TMAO) and urea were elevated by December 15 and continued to increase in fish held in ambient conditions. In contrast, fish held under warm conditions exhibited decreased glycerol and urea content in plasma, muscle and liver. Plasma and liver TMAO levels also decreased in these fish while muscle TMAO did not vary from the initial values. The activity of liver enzymes involved with the production of glycerol did not differ significantly between groups and had decreased by the end of the study. Antifreeze protein (AFP) expression increased over the duration of the experiment. In January samples, AFP activity (thermal hysteresis) did not vary significantly between groups but mRNA levels were significantly lower in the smelt held at warm temperatures.

Crocin attenuates CCl4-induced liver fibrosis via PPAR-γ mediated modulation of inflammation and fibrogenesis in rats

2020 ◽  
Vol 39 (12) ◽  
pp. 1639-1649 ◽  
Author(s):  
J Chhimwal ◽  
S Sharma ◽  
P Kulurkar ◽  
V Patial
Keyword(s):  
Liver Fibrosis ◽  
Liver Tissue ◽  
Transforming Growth Factor ◽  
Liver Enzymes ◽  
Pathological Condition ◽  
Smooth Muscle Actin ◽  
Intraperitoneal Administration ◽  
Crocus Sativus ◽  
Mrna Levels ◽  
Ppar Γ

Background: Liver fibrosis is a chronic pathological condition with a leading cause of liver-related mortality worldwide. In the present study, we have evaluated the antifibrotic effect of crocin, a carotenoid present in the stigma of Crocus sativus, and also explored its putative mechanism of action. Methods: Liver fibrosis was induced by intraperitoneal administration of 30% carbon tetrachloride (CCl4). The crocin was administered orally at 20, 40 and 80 mg/kg body weight along with CCl4 up to 8 weeks. Results: Chronic exposure to CCl4 resulted in elevated levels of liver enzymes and reduced cytochrome P450 2E1 (CYP2E1) activity in the liver. The liver tissue showed cellular swelling, vacuolization, necrosis, infiltration of inflammatory cells and fibrotic changes. The crocin treatment significantly lowered the levels of liver enzymes in serum and improved the liver CYP2E1 mRNA levels. The pathological changes in the liver were also lowered by crocin treatment. The level of pro-inflammatory cytokines, nuclear factor-kappa B, interleukin-6 and tumor necrosis factor α and fibrogenic factor, transforming growth factor β, and α-smooth muscle actin were elevated by the CCl4 in the liver tissue. However, crocin treatment at different doses significantly reduced the expression of these factors. The increased caspase 3/7 activity was also lowered by crocin. CCl4 administration decreased the expression of peroxisome proliferator-activated receptor γ (PPAR-γ) in liver tissue. The improved PPAR-γ expression in the liver by crocin treatment indicates its role in the therapeutic effect of crocin. Conclusions: Crocin attenuated the various events in the progression of liver fibrosis via PPAR-γ mediated modulation of inflammatory and fibrogenic pathways.

Intracellular osmoregulatory role of amino acids and urea in marine elasmobranchs

1976 ◽  
Vol 230 (4) ◽  
pp. 925-931 ◽  
Author(s):  
RP Forster ◽  
L Goldstein
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Extracellular Fluid ◽  
Raja Erinacea ◽  
Urea Content ◽  
Intracellular Amino Acid ◽  
Trimethylamine Oxide ◽  
Total Amino Acids ◽  
Positive Materials

Little skates, Raja erinacea, and stingrays, Dasyatis americana, were gradually transferred over a period of 4-5 days from full strength to approximatley 50% seawater. Plasma and muscle osmolarity fell. Hematocrits were essentially unchanged. Extracellular fluid volume (ECF) of muscle, estimated as the chloride space, increased 70% during this period. Regulation of muscle cell volume was associated with sharp declines in cellular concentrations of total amino acids (ninhydrin-positive materials) and urea. The osmoregulatory importance of the free amino acid pool in erythrocytes and muscle was a particularly prominent feature in both species. Intracellular amino acid concentration in R. erinacea muscle fell from 214 to 144 mmol/liter during transfer to 50% seawater, urea from 398 to 264, and trimethylamine oxide (TMAO) dropped from 63.9 to 35.8 mmol/liter. TMAO plasma levels were similar in stingray and skate, but muscle TMAO concentrations were much higher in the former. Urea content in stingray plasma greatly exceeded that in R. erinacea-630 and 574 mmol/liter in two specimens-perhaps the highest recorded.

Effect of Snow Removal on Typhula Blight Development at High Elevation Golf Courses in Colorado

2013 ◽  
Vol 14 (1) ◽  
pp. 12 ◽  
Author(s):  
Tamla Blunt ◽  
Tony Koski ◽  
Ned Tisserat
Keyword(s):  
Kentucky Bluegrass ◽  
High Elevation ◽  
Early Spring ◽  
Disease Suppression ◽  
Late Winter ◽  
Putting Greens ◽  
Freeze Avoidance ◽  
Snow Removal ◽  
Freeze Damage ◽  
High Elevations

Golf course superintendents at high elevations in Colorado apply fungicides in late October before permanent snow cover to suppress Typhula blight development. Many remove snow from putting greens in late winter or early spring assuming this practice helps suppress Typhula blight late into the snow season. They also remove snow to prevent ice formation and freeze damage to turfgrass during snowmelt. However, the benefits of spring snow removal in disease suppression and freeze avoidance have not been demonstrated in Colorado. We compared Typhula blight severity and turfgrass health in Kentucky bluegrass and annual bluegrass fairways where snow was removed weekly from late October through mid-November, from early- to mid-March until the end of the snow period, or not removed. Fall snow removal did not reduce Typhula blight severity compared to no snow removal, but it did result in freeze damage to annual, but not Kentucky bluegrass. Spring snow removal had no effect on Typhula blight severity or freeze damage. Thus the practice of snow removal was of no apparent benefit in our studies. Accepted for publication 3 June 2013. Published 21 August 2013.

scholarly journals Remote Ischemic Preconditioning and Diazoxide Protect from Hepatic Ischemic Reperfusion Injury by Inhibiting HMGB1-Induced TLR4/MyD88/NF-κB Signaling

2019 ◽  
Vol 20 (23) ◽  
pp. 5899 ◽  
Author(s):  
Won Uk Koh ◽  
Jiye Kim ◽  
Jooyoung Lee ◽  
Gi-Won Song ◽  
Gyu Sam Hwang ◽  
...  
Keyword(s):  
Mouse Model ◽  
Protective Effect ◽  
Ischemic Preconditioning ◽  
Liver Enzymes ◽  
Ischemia Reperfusion ◽  
Underlying Mechanism ◽  
Remote Ischemic Preconditioning ◽  
Mrna Levels ◽  
Hepatic Ischemia ◽  
Hepatic Ischemia Reperfusion

Remote ischemic preconditioning (RIPC) is known to have a protective effect against hepatic ischemia-reperfusion (IR) injury in animal models. However, the underlying mechanism of action is not clearly understood. This study examined the effectiveness of RIPC in a mouse model of hepatic IR and aimed to clarify the mechanism and relationship of the ATP-sensitive potassium channel (KATP) and HMGB1-induced TLR4/MyD88/NF-κB signaling. C57BL/6 male mice were separated into six groups: (i) sham-operated control, (ii) IR, (iii) RIPC+IR, (iv) RIPC+IR+glyburide (KATP blocker), (v) RIPC+IR+diazoxide (KATP opener), and (vi) RIPC+IR+diazoxide+glyburide groups. Histological changes, including hepatic ischemia injury, were assessed. The levels of circulating liver enzymes and inflammatory cytokines were measured. Levels of apoptotic proteins, proinflammatory factors (TLR4, HMGB1, MyD88, and NF-κB), and IκBα were measured by Western blot and mRNA levels of proinflammatory cytokine factors were determined by RT-PCR. RIPC significantly decreased hepatic ischemic injury, inflammatory cytokine levels, and liver enzymes compared to the corresponding values observed in the IR mouse model. The KATP opener diazoxide + RIPC significantly reduced hepatic IR injury demonstrating an additive effect on protection against hepatic IR injury. The protective effect appeared to be related to the opening of KATP, which inhibited HMGB1-induced TRL4/MyD88/NF-kB signaling.

Room temperature hysteretic spin crossover in a new cyanoheterometallic framework

2019 ◽  
Vol 55 (23) ◽  
pp. 3359-3362 ◽  
Author(s):  
Volodymyr M. Hiiuk ◽  
Sergiu Shova ◽  
Aurelian Rotaru ◽  
Vadim Ksenofontov ◽  
Igor O. Fritsky ◽  
...  
Keyword(s):  
Room Temperature ◽  
Spin Crossover ◽  
Thermal Hysteresis ◽  
Ambient Conditions

A new iron(ii)-based spin-crossover compound with thermal hysteresis operating under ambient conditions is reported.

scholarly journals Resveratrol Ameliorates Experimental Alcoholic Liver Disease by Modulating Oxidative Stress

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
He Peiyuan ◽  
Hou Zhiping ◽  
Song Chengjun ◽  
Wang Chunqing ◽  
Li Bingqing ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Enzymes ◽  
Liver Disease ◽  
Alcoholic Liver Disease ◽  
Caspase 3 ◽  
Liver Enzymes ◽  
Female Rats ◽  
Transcriptional Level ◽  
Mrna Levels ◽  
Protein Levels

The aim of this study was to investigate the hepatoprotective effects of resveratrol in alcoholic liver disease (ALD). Alcohol was administered to healthy female rats starting from 6% (v/v) and gradually increased to 20% (v/v) by the fifth week. After 16 weeks of intervention, liver enzymes (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) were analyzed using a chemistry analyzer, while hepatic antioxidant enzymes, oxidative stress markers, and caspase 3 activity were assessed using ELISA kits. Furthermore, hepatic CYP2E1 protein levels and mRNA levels of antioxidant and inflammation-related genes were determined using western blotting and RT-PCR, respectively. The results showed that resveratrol significantly attenuated alcohol-induced elevation of liver enzymes and improved hepatic antioxidant enzymes. Resveratrol also attenuated alcohol-induced CYP2E1 increase, oxidative stress, and apoptosis (caspase 3 activity). Moreover, genes associated with oxidative stress and inflammation were regulated by resveratrol supplementation. Taken together, the results suggested that resveratrol alleviated ALD through regulation of oxidative stress, apoptosis, and inflammation, which was mediated at the transcriptional level. The data suggests that resveratrol is a promising natural therapeutic agent against chronic ALD.

Applications of PTC-51 Gas Turbine Inlet Air Conditioning Equipment

2011 ◽  
Author(s):  
Tina L. Toburen
Keyword(s):  
Gas Turbine ◽  
Air Conditioning ◽  
Performance Test ◽  
Early Spring ◽  
Design Phase ◽  
Ambient Conditions ◽  
Ambient Temperatures ◽  
Summer Peak ◽  
Turbine Inlet ◽  
Conditioning Equipment

The ASME Performance Test Code PTC-51 “Gas Turbine Inlet Air Conditioning Equipment” (PTC-51) [1] is currently in its final editing phase prior to publication. This paper will give a brief introduction to the code and outline some examples of how to apply PTC-51 to actual testing scenarios. Many plants are designed for hot summer peak ambient temperatures, but need to be tested in early spring for substantial completion and commercial contractual requirements. PTC-51 puts limits on the ambient conditions in which you can test inlet air conditioning equipment. Understanding these limits during the contract and design phase is critical if code-level testing will be a requirement for final completion.

scholarly journals Overexpression of a SOC1-Related Gene Promotes Bud Break in Ecodormant Poplars

2021 ◽  
Vol 12 ◽  
Author(s):  
Daniela Gómez-Soto ◽  
José M. Ramos-Sánchez ◽  
Daniel Alique ◽  
Daniel Conde ◽  
Paolo M. Triozzi ◽  
...  
Keyword(s):  
Expression Analysis ◽  
Early Spring ◽  
Shoot Meristem ◽  
Bud Break ◽  
Mrna Levels ◽  
Related Gene ◽  
Annual Variations ◽  
Hybrid Poplars ◽  
Growth Transitions ◽  
Temporal Events

Perennial species in the boreal and temperate regions are subject to extreme annual variations in light and temperature. They precisely adapt to seasonal changes by synchronizing cycles of growth and dormancy with external cues. Annual dormancy–growth transitions and flowering involve factors that integrate environmental and endogenous signals. MADS-box transcription factors have been extensively described in the regulation of Arabidopsis flowering. However, their participation in annual dormancy–growth transitions in trees is minimal. In this study, we investigate the function of MADS12, a Populus tremula × alba SUPPRESSOR OF CONSTANS OVEREXPRESSION 1 (SOC1)-related gene. Our gene expression analysis reveals that MADS12 displays lower mRNA levels during the winter than during early spring and mid-spring. Moreover, MADS12 activation depends on the fulfillment of the chilling requirement. Hybrid poplars overexpressing MADS12 show no differences in growth cessation and bud set, while ecodormant plants display an early bud break, indicating that MADS12 overexpression promotes bud growth reactivation. Comparative expression analysis of available bud break-promoting genes reveals that MADS12 overexpression downregulates the GIBBERELLINS 2 OXIDASE 4 (GA2ox4), a gene involved in gibberellin catabolism. Moreover, the mid-winter to mid-spring RNAseq profiling indicates that MADS12 and GA2ox4 show antagonistic expression during bud dormancy release. Our results support MADS12 participation in the reactivation of shoot meristem growth during ecodormancy and link MADS12 activation and GA2ox4 downregulation within the temporal events that lead to poplar bud break.

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