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2021 ◽  
Vol 11 (6) ◽  
pp. 137-143
Author(s):  
. Kalpana Devi K. K ◽  
Prakash Sahaya leon J.

In agriculture, excessive use of various pesticides had increased in developing countries. These pesticides may be highly toxic, not only to aquatic organisms like fishes but also to humans. In recent years, synthetic pyrethroids were developed for major uses in various agriculture practices and public health purposes. We aim to find the toxic Effect of Cypermethrin on Freshwater Fish Oreochromis mossambicus (Tilapia). The fish Oreochromis mossambicus were exposed for 30 days to various sub lethal concentrations (1/10, 1/20, and 1/30) of cypermethrin. After completion of a 30 days exposure, the fish Oreochromis mossambicus was sacrificed and tissue samples of muscle, liver, and kidney were analyzed. Decreased value of ALP, ACP, and Increased value of AST, ALT was observed in all the sub lethal exposure of cypermethrin on treated freshwater fish Oreochromis mossambicus at 30 days on comparing with the control group. High variation of AST and ALT were observed in the liver at 1/10th concentration of cypermethrin and elevated variation of ALP and ACP was observed in the liver at 1/10th concentration of sub lethal level for 30 days exposure. While comparing with the control group, the effects of cypermethrin on experimental fish showed increased levels of AST, ALT in the tissues of muscle, liver, and kidney of O. mossambicus, and the level of ACP and ALP were found in a decreased manner. Increased levels of ALT and AST activity observed in freshwater fishes may be due to the reduction of metabolic activity and concentration of ACP and ALP in various tissues due to cellular necrosis. In the present study, we found that the effect of cypermethrin alters the activity of various enzymes in freshwater fish Oreochromis mossambicus. It is concluded from this study that exposure to cypermethrin affects the enzyme activities of fish.


2021 ◽  
Author(s):  
Xia Chaoxu ◽  
Nie Gaozhong ◽  
Fan Xiwei ◽  
Li Huayue ◽  
Zhou Junxue ◽  
...  

Author(s):  
T. Deepak ◽  
G. B. Sanjay ◽  
C. S. Shivakumar

Water sources of almost all regions in India are carrying the unbearable burden of dangerous pollutants. The release of waste products and anthropogenic wastes run-off has contributed to aquatic pollution. The environment has become a storehouse for chemical pollutant which infiltrate into the aquatic environment, including estuarine, thus immobilizing the aquatic biota, among the heavy metals. Chromium is a heavy metal which has both beneficial and harmful effect on organisms. It is highly toxic and carcinogenic. Many industries are disposing of chemical pollutants to the water. These disposals contain many chemicals, including Chromium. The purpose of this review was to check the accumulation and concentration of heavy metals in different organs of freshwater fishes that come in contact with the water contaminated with heavy metals. The subjected fish were exposed to Chromium (Cr) at the sub-lethal level at a concentration of 40mg/L in 96 hours. During the observation period, the fishes shown some behavioral changes like erratic swimming, slow motility, suffocation, and the scales become thin and decolorized. In the gill region, the gill filaments become swollen, and gill rackers become thick, and curling of lamellae was noticed, and it is caused due to the Chromium build-upon gills. At the region of the caudal fin, permanent bending of the tail was observed. The Chromium also affects other vital organs like the spleen and gut region. LC50 was found in 96 hours. The result indicates that Chromium is highly toxic and has deleterious effects on aquatic life. Humans are also affected by the intake of fishes for primary people of those areas where the leading food is fish.


2021 ◽  
Vol 11 ◽  
Author(s):  
Filipa Lopes-Coelho ◽  
Filipa Martins ◽  
Ana Hipólito ◽  
Cindy Mendes ◽  
Catarina O. Sequeira ◽  
...  

The activation of endothelial cells (ECs) is a crucial step on the road map of tumor angiogenesis and expanding evidence indicates that a pro-oxidant tumor microenvironment, conditioned by cancer metabolic rewiring, is a relevant controller of this process. Herein, we investigated the contribution of oxidative stress-induced ferroptosis to ECs activation. Moreover, we also addressed the anti-angiogenic effect of Propranolol. We observed that a ferroptosis-like mechanism, induced by xCT inhibition with Erastin, at a non-lethal level, promoted features of ECs activation, such as proliferation, migration and vessel-like structures formation, concomitantly with the depletion of reduced glutathione (GSH) and increased levels of oxidative stress and lipid peroxides. Additionally, this ferroptosis-like mechanism promoted vascular endothelial cadherin (VE-cadherin) junctional gaps and potentiated cancer cell adhesion to ECs and transendothelial migration. Propranolol was able to revert Erastin-dependent activation of ECs and increased levels of hydrogen sulfide (H2S) underlie the mechanism of action of Propranolol. Furthermore, we tested a dual-effect therapy by promoting ECs stability with Propranolol and boosting oxidative stress to induce cancer cell death with a nanoformulation comprising selenium-containing chrysin (SeChry) encapsulated in a fourth generation polyurea dendrimer (SeChry@PUREG4). Our data showed that novel developments in cancer treatment may rely on multi-targeting strategies focusing on nanoformulations for a safer induction of cancer cell death, taking advantage of tumor vasculature stabilization.


2021 ◽  
Vol 42 (2) ◽  
pp. 58-64
Author(s):  
A. A. Annongu ◽  
O. A. Adeyemi ◽  
S. A. O. Bolu ◽  
R. M. O. Kayode ◽  
F. E. Sola-Ojo

Graded levels of full-fat undecorticated Moringa oleifera seed meal (MOSM) were evaluated in diets of 96-day old broilers at 2.5, 5.0 and 7.5% while a maize-soybean diet was used as a reference diet. Nutrients utilization by the broilers and effects of the virgin dietary MOSMon serum chemistry, haematology and some bio-data-protein efficiency ratio (PER) and nitrogen metabolism (NM) were used as response criteria for the evaluation. The metabolic utilization of nutrients, most of the serum chemistry and haematological parameters decreased in response to increasing dietary levels of MOSM except values on products of metabolism like creatinine, uric acid, bilirubin and conjugated bilirubin that tended to elevate with increasing levels of dietary unprocessed MOSM. Since no mortality was recorded in this experiment even at 7.5% MOSM inclusion, further research is on-going to determine the lethal level to poultry including other monogastric animals. 


2020 ◽  
Vol 82 (8) ◽  
pp. 553-559
Author(s):  
Medelin Kant ◽  
Julie Angle ◽  
William M. Hammond ◽  
Henry D. Adams

Climate change is causing widespread forest mortality due to intensified drought conditions. In light of a dynamically changing planet, understanding when forest die-off will occur is vital in predicting forest response to future climate trends. The Environmental Ecology Lab studies plant physiological response to drought stress to determine the lethal level of drought for pinyon pine. This drought research inspired this high school biology lesson, which addresses the NGSS Performance Expectation HS-LS4-6. Students engage in a climate change discussion regarding the devastation of California wildfires. Ongoing research in the lab is then introduced, leading students to design their own drought experiment using radish plants. Students determine an effective drought detector as a solution to mitigate human-induced climate change. Experimental data are statistically tested using R, to determine the effectiveness of drought detectors. To place their observations in a global context, students research the NASA Global Climate Change website to provide evidence to support their claim of human-induced climate change and relate this to a reduction in biodiversity. In a final presentation, groups share their most effective physiological measurement and propose potential applications of drought detection in mitigating adverse impacts of climate change.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7020 ◽  
Author(s):  
James W.A. Murphy ◽  
Abby C. Collier ◽  
Robert H. Richmond

The impacts of continued degradation of watersheds on coastal coral reefs world-wide is alarming, and action addressing anthropogenic stressors and subsequent rehabilitation of watersheds and adjacent reefs is an urgent priority. The aim of this study is to develop and improve the use of antioxidant enzymes as bioindicators of stress in coral species. In order to fully develop such tools, it is necessary to first understand baseline cycling of these enzymes within coral tissues. Due to inherent links between reproduction and oxidative stress, these aims may be facilitated by sampling coral tissues over reproductively-linked lunar cycles to determine variations from baseline. By developing a greater understanding of biochemical markers of stress in corals, specifically antioxidant defense enzymes catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), and superoxide dismutase (SOD) in Hawaiian Pocillopora damicornis, we have provided molecular tools that identify thresholds of stress on coral reefs. Our results suggest that the coral reproductive state is a significant factor affecting the activity of antioxidant enzymes. Specifically, CAT and GR display maximum activity during peak reproductive state. Whereas significant maximal Se-independent GPx and SOD activity was measured during off-peak reproductive cycles. Such insight into the cyclical variation of the activity of these enzymes should be applied towards differentiating the influence of natural biological activity cycling in diagnostic tests identifying the effects of different physical environmental factors and chemical pollutants on coral health. Through the development and application of these molecular biomarkers of stress, we look to improve our ability to identify problems at the sub-lethal level, when action can be taken to mitigate a/biotic impacts.


Author(s):  
Disha B. Sheth ◽  
Miklόs Gratzl

Blood capillaries deliver oxygen and nutrients to surrounding micro-regions of tissue and carry away metabolic waste. In normal tissue, capillaries are close enough to keep all the cells viable. In solid tumours, the capillary system is chaotic and typical inter-capillary distances are larger than in normal tissue. Therefore, hypoxic regions develop. Drug molecules may not reach these areas at concentrations above the lethal level. The combined effect of low drug concentrations and local hypoxia, often exacerbated by acidity, leads to therapy failure. To better understand the interplay between hypoxia and poor drug penetration, oxygenation needs to be assessed in different areas of inter-capillary tissue. The multicellular tumour spheroid is a well-established three-dimensional (3D) in vitro model of the capillary microenvironment. It is used to mimic nascent tumours and micro-metastases as well. In this work, we demonstrate for the first time that dynamic intra-spheroidal oxygen maps can be obtained at the 3D multicellular tumour hemi-spheroid (MCH) using a non-invasive microelectrode array. The same oxygen distributions exist inside the equivalent but less accessible full spheroid. The MCH makes high throughput—high content analysis of spheroids feasible and thus can assist studies on basic cancer biology, drug development and personalized medicine.


2019 ◽  
Author(s):  
Zuyi C. Gooley ◽  
Aaron C. Gooley

AbstractA twelve-month study was conducted on changes in fatty acid composition and pesticide residues in honeybees and beebread. In honeybees, saturated fatty acid and monounsaturated fatty acid gradually increased as summer began then decreased when spring started, and polyunsaturated fatty acid had an opposite seasonal trend. Similar fluctuation was observed in the beebread collected from the same hive as those honeybees through summer to fall, especially in the essential fatty acids omega-6 and omega-3. Honeybees’ lipid metabolism can be disrupted after being exposed to a sub-lethal level of pesticide. Although three out of sixteen analyzed pesticides were detected in beebread samples summer through fall in our study, we were not able to find any negative affect of those pesticides on the honeybees’ fatty acid composition. Temporary field-realistic pesticide exposure may weaken honeybees but are unlikely to show any reflection in their fat bodies if the colony was otherwise healthy.


2018 ◽  
Author(s):  
James WA Murphy ◽  
Abby C Collier ◽  
Robert H Richmond

The impacts of continued degradation of watersheds on coastal coral reefs world-wide is alarming. Action addressing anthropogenic stressors and subsequent rehabilitation of watersheds and adjacent reefs is an urgent priority. The aim of this study is to develop and improve the use of antioxidant enzymes as biomarkers in coral species. In order to fully develop such tools, it is necessary to perform sampling of coral tissues over reproductive cycles to determine variations from baseline. By developing a greater understanding of biochemical markers of stress in corals, specifically antioxidant defense enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR), we have provided molecular tools that identify thresholds of stress on coral reefs. Our results suggest that the coral reproductive state is a significant factor affecting the activity of antioxidant enzymes. Specifically, CAT (65.92 mmol/min/mg protein, p = 0.0177) and GR (12.64 nmol/min/mg protein, p < 0.0001) display maximum activity during peak reproductive state. Whereas significant maximal SOD (154.92 nmol/min/mg protein, p < 0.0454) and Se-independent GPx (5.35 nmol/min/mg protein, p = 0.0001) activity was measured during off-peak reproductive cycles. Such insight into the cyclical variation of the activity of these enzymes should be applied towards differentiating the influence of natural biological activity cycling in diagnostic tests identifying the effects of different physical environmental factors and chemical pollutants on coral health. Through the development and application of these molecular biomarkers of stress, we look to improve our ability to identify problems at the sub-lethal level, when action can be taken to mitigate a/biotic impacts.


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