scholarly journals Low Dose Coagulant and Local Soil Ballast Effectively Remove Cyanobacteria (Microcystis) from Tropical Lake Water without Cell Damage

Water ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 111
Author(s):  
Somjate Thongdam ◽  
Anthony C. Kuster ◽  
Brian J. Huser ◽  
Anootnara T. Kuster
Keyword(s):  
Zeta Potential ◽  
Lake Water ◽  
Cellular Structure ◽  
Lake Restoration ◽  
Low Dose ◽  
Morphological Changes ◽  
Cell Damage ◽  
Tropical Lake ◽  
Chl A ◽  
Local Soil

The combination of a low dose of coagulant with a ballast, also known as “flock and sink,” has been proposed as a lake restoration and cyanobacteria bloom management strategy. The effectiveness of this technique using aluminum sulfate (alum) as a coagulant and a local soil (LS) from Thailand as a ballast in eutrophic water dominated by positively buoyant Microcystis colonies collected from a tropical lake was investigated by measuring changes in chlorophyll-a (chl-a), pH, and zeta potential. Cell integrity was also evaluated using scanning electron microscopy. Results showed that alum alone could reduce chl-a (up to 60% to 83%) at doses (higher than 3 to 6 mg Al/L) dependent on the initial pH (7.6 to 8.2) and initial chl-a concentration (138 to 615 µg/L) of the lake water but resulted in morphological changes to cellular structure and generally required a dose that reduced pH to <7. LS ballast alone was able to reduce chl-a concentrations (up to 26% at highest dose of 400 mg/L) and caused no significant changes to pH or zeta potential. Combining a low dose of alum (2 mg Al/L) with some amount of LS ballast (50 to 400 mg/L) created an interaction effect that resulted in 81 to 88% reduction in chl-a without changes to zeta potential or morphological changes to cellular structure. Flock and sink may serve a niche role in lake restoration when positively buoyant cyanobacteria are present in the water column during time of treatment. This research showed that an 800% increase in ballast dose resulted in about an 8% reduction in chl-a when combined with 2 mg Al/L of alum. Therefore, it is recommended that ballast dose should be determined by considering its phosphorus sorption capacity and the potentially releasable phosphorus in the lake sediment in order to realize long-term reductions in sediment nutrient release.

scholarly journals The Neuroinflammatory Role of Pericytes in Epilepsy

Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 759
Author(s):  
Gaku Yamanaka ◽  
Fuyuko Takata ◽  
Yasufumi Kataoka ◽  
Kanako Kanou ◽  
Shinichiro Morichi ◽  
...  
Keyword(s):  
Proinflammatory Cytokines ◽  
Current Knowledge ◽  
Morphological Changes ◽  
Cell Damage ◽  
Neurovascular Unit ◽  
Experimental Studies ◽  
Intractable Epilepsy ◽  
In Vivo Studies

Pericytes are a component of the blood–brain barrier (BBB) neurovascular unit, in which they play a crucial role in BBB integrity and are also implicated in neuroinflammation. The association between pericytes, BBB dysfunction, and the pathophysiology of epilepsy has been investigated, and links between epilepsy and pericytes have been identified. Here, we review current knowledge about the role of pericytes in epilepsy. Clinical evidence has shown an accumulation of pericytes with altered morphology in the cerebral vascular territories of patients with intractable epilepsy. In vitro, proinflammatory cytokines, including IL-1β, TNFα, and IL-6, cause morphological changes in human-derived pericytes, where IL-6 leads to cell damage. Experimental studies using epileptic animal models have shown that cerebrovascular pericytes undergo redistribution and remodeling, potentially contributing to BBB permeability. These series of pericyte-related modifications are promoted by proinflammatory cytokines, of which the most pronounced alterations are caused by IL-1β, a cytokine involved in the pathogenesis of epilepsy. Furthermore, the pericyte-glial scarring process in leaky capillaries was detected in the hippocampus during seizure progression. In addition, pericytes respond more sensitively to proinflammatory cytokines than microglia and can also activate microglia. Thus, pericytes may function as sensors of the inflammatory response. Finally, both in vitro and in vivo studies have highlighted the potential of pericytes as a therapeutic target for seizure disorders.

Surface phenomena related to applications regarding optimum dosages of casein superplasticizer in self-leveling underlayment cements

2019 ◽  
Vol 74 (7-8) ◽  
pp. 607-611 ◽  
Author(s):  
Hang Bian ◽  
Johann Plank
Keyword(s):  
Zeta Potential ◽  
Low Dose ◽  
Pore Solution ◽  
Time Span ◽  
High Dose ◽  
Surface Phenomena ◽  
Adsorption State ◽  
Test Flow ◽  
Dispersive Power ◽  
Dose Levels

AbstractWe experimentally investigated the optimum dosage of casein superplasticizer (SP) in self-leveling underlayments (SLUs). The undersaturated adsorption state of casein in cement pore solution was characterized by zeta potential measurements. Different amounts of casein were dosed in SLU pastes and their dispersion performance was investigated by a mini slump test. Flow values of the SLU pastes were found to increase with casein dosage, but an obvious segregation of the pastes was observed at high dose levels of SP. At an SP dosage of 0.12 wt.% bwob (by weight of binder), a homogeneous SLU paste with a spread flow of >15 cm over a time span of 30 min was obtained, which was identified as the optimum casein dosage for SLUs. Casein was found to adsorb significantly onto the surface of cement, thus producing strong dispersive power at low dose levels.

scholarly journals Removal of Positively Buoyant Planktothrix rubescens in Lake Restoration

Toxins ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 700 ◽  
Author(s):  
Miquel Lürling ◽  
Maíra Mucci ◽  
Guido Waajen
Keyword(s):  
Hydrogen Peroxide ◽  
The Netherlands ◽  
Chlorophyll A ◽  
Lake Restoration ◽  
Low Dose ◽  
Cyanobacterial Blooms ◽  
Similar Species ◽  
Modified Bentonite ◽  
Planktothrix Rubescens ◽  
Polyaluminium Chloride

The combination of a low-dose coagulant (polyaluminium chloride—‘Floc’) and a ballast able to bind phosphate (lanthanum modified bentonite, LMB—‘Sink/Lock’) have been used successfully to manage cyanobacterial blooms and eutrophication. In a recent ‘Floc and Lock’ intervention in Lake de Kuil (the Netherlands), cyanobacterial chlorophyll-a was reduced by 90% but, surprisingly, after one week elevated cyanobacterial concentrations were observed again that faded away during following weeks. Hence, to better understand why and how to avoid an increase in cyanobacterial concentration, experiments with collected cyanobacteria from Lakes De Kuil and Rauwbraken were performed. We showed that the Planktothrix rubescens from Lake de Kuil could initially be precipitated using a coagulant and ballast but, after one day, most of the filaments resurfaced again, even using a higher ballast dose. By contrast, the P. rubescens from Lake Rauwbraken remained precipitated after the Floc and Sink/Lock treatment. We highlight the need to test selected measures for each lake as the same technique with similar species (P. rubescens) yielded different results. Moreover, we show that damaging the cells first with hydrogen peroxide before adding the coagulant and ballast (a ‘Kill, Floc and Lock/Sink’ approach) could be promising to keep P. rubescens precipitated.

scholarly journals Low-Dose Ribavirin Treatments Attenuate Neuroinflammatory Activation of BV-2 Cells by Interfering with Inducible Nitric Oxide Synthase

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Iva Bozic ◽  
Danijela Savic ◽  
Marija Jovanovic ◽  
Ivana Bjelobaba ◽  
Danijela Laketa ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Low Dose ◽  
Nitrosative Stress ◽  
Morphological Changes ◽  
Necrosis Factor Alpha ◽  
External Threats ◽  
Cytokine Tumor Necrosis Factor ◽  
Induced Apoptosis ◽  
Oxide Synthase

Microglia play a key role in defending central nervous system from various internal and external threats. However, their excessive and/or chronic activation is associated with deleterious effects in a variety of neurodegenerative diseases. Previously, we have shown that ribavirin when applied in clinically relevant dosage (10 μM) modulates activated microglia in complex fashion inducing both anti- and proinflammatory effects, simultaneously causing cytotoxicity. Here, we examined potential of low-dose ribavirin (0.1 and 1 μM) to modulate activated BV-2 microglia. Morphological and functional activation of BV-2 cells was achieved with lipopolysaccharide (LPS) stimulation. Our results demonstrated that low-dose ribavirin did not induce cell death, while 10 μM ribavirin promoted LPS induced apoptosis. We determined that 1 μM ribavirin was equally efficient in deactivation of LPS induced morphological changes as 10 μM ribavirin treatment. Ribavirin showed halfway success in reducing markers of functional activation of microglia. Namely, none of the doses had effect on LPS triggered production of proinflammatory cytokine tumor necrosis factor alpha. On the other hand, low-dose ribavirin proved its effectiveness in reduction of another inflammatory mediator, nitric oxide, by inhibiting inducible form of nitric oxide synthase. Our results imply that low-dose ribavirin may alleviate nitrosative stress during neuroinflammation.

scholarly journals Seasonal forecasting of lake water quality and algal bloom risk using a continuous Gaussian Bayesian network

2022 ◽  
Author(s):  
Leah Jackson-Blake ◽  
François Clayer ◽  
Sigrid Haande ◽  
James Sample ◽  
Jannicke Moe
Keyword(s):  
Water Quality ◽  
Bayesian Network ◽  
Lake Water ◽  
Regression Tree ◽  
Predictive Performance ◽  
Lake Water Quality ◽  
Water Quality Prediction ◽  
Chl A ◽  
First Choice ◽  
Gaussian Bayesian Network

Abstract. Freshwater management is challenging, and advance warning that poor water quality was likely, a season ahead, could allow for preventative measures to be put in place. To this end, we developed a Bayesian network (BN) for seasonal lake water quality prediction. BNs have become popular in recent years, but the vast majority are discrete. Here we developed a Gaussian Bayesian network (GBN), a simple class of continuous BN. The aim was to forecast, in spring, total phosphorus (TP), chlorophyll-a (chl-a), cyanobacteria biovolume and water colour for the coming growing season (May–October) in lake Vansjø in southeast Norway. To develop the model, we first identified controls on inter-annual variability in water quality using correlations, scatterplots, regression tree based feature importance analysis and process knowledge. Key predictors identified were lake conditions the previous summer, a TP control on algal variables, a colour-cyanobacteria relationship, and weaker relationships between precipitation and colour and between wind and chl-a. These variables were then included in the GBN and conditional probability densities were fitted using observations (≤ 39 years). GBN predictions had R2 values of 0.37 (cyanobacteria) to 0.75 (colour) and classification errors of 32 % (TP) to 13 % (cyanobacteria). For all but lake colour, including weather nodes did not improve predictive performance (assessed through cross validation). Overall, we found the GBN approach to be well-suited to seasonal water quality forecasting. It was straightforward to produce probabilistic predictions, including the probability of exceeding management-relevant thresholds. The GBN could be purely parameterised using observed data, despite the small dataset. This wasn’t possible using a discrete BN, highlighting a particular advantage of using GBNs when sample sizes are small. Although low interannual variability and high temporal autocorrelation in the study lake meant the GBN performed similarly to a seasonal naïve forecast, we believe the forecasting approach presented could be useful in areas with higher sensitivity to catchment nutrient delivery and seasonal climate, and for forecasting at shorter time scales (e.g. daily to monthly). Despite the parametric constraints of GBNs, their simplicity, together with the relative accessibility of BN software with GBN handling, means they are a good first choice for BN development, particularly when datasets for model training are small.

scholarly journals Role of Oxidative Stress in the Senescence Pattern of Auditory Cells in Age-Related Hearing Loss

Antioxidants ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1497
Author(s):  
Luz del Mar Rivas-Chacón ◽  
Sofía Martínez-Rodríguez ◽  
Raquel Madrid-García ◽  
Joaquín Yanes-Díaz ◽  
Juan Ignacio Riestra-Ayora ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Hearing Loss ◽  
Molecular Mechanisms ◽  
Morphological Changes ◽  
Cell Damage ◽  
Stria Vascularis ◽  
Organ Of Corti ◽  
Age Related ◽  
Age Related Hearing Loss

Age-related hearing loss (ARHL) is an increasing and gradual sensorineural hearing dysfunction. Oxidative stress is an essential factor in developing ARHL; additionally, premature senescence of auditory cells induced by oxidative stress can produce hearing loss. Hydrogen peroxide (H2O2) represents a method commonly used to generate cellular senescence in vitro. The objective of the present paper is to study H2O2-induced senescence patterns in three auditory cell lines (House Ear Institute-Organ of Corti 1, HEI-OC1; organ of Corti, OC-k3, and stria vascularis, SV-k1 cells) to elucidate the intrinsic mechanisms responsible for ARHL. The auditory cells were exposed to H2O2 at different concentrations and times. The results obtained show different responses of the hearing cells concerning cell growth, β-galactosidase activity, morphological changes, mitochondrial activation, levels of oxidative stress, and other markers of cell damage (Forkhead box O3a, FoxO3a, and 8-oxoguanine, 8-oxoG). Comparison between the responses of these auditory cells to H2O2 is a helpful method to evaluate the molecular mechanisms responsible for these auditory cells’ senescence. Furthermore, this in vitro model could help develop anti-senescent therapeutic strategies for the treatment of AHRL.

scholarly journals Cellular Damage After Prolonged Low-Dose Exposure of Neonicotinoid in Rats

2021 ◽  
Author(s):  
Rahat Naseer ◽  
Affan Tariq ◽  
Munazza Raza Mirza ◽  
Muhammad Rashid ◽  
Syed Qasim Raza ◽  
...  
Keyword(s):  
Vitamin E ◽  
Low Dose ◽  
Prolonged Exposure ◽  
Cell Damage ◽  
Hematological Parameters ◽  
Treated Group ◽  
Alpha Tocopherol ◽  
Cellular Damage ◽  
Control Group ◽  
New Class

Abstract Background; Dinotefuran is a new class of neonicotinoids claimed to be harmless to mammals and humans. This claim was daunted by the documented effect of dinotefuran on honeybees and further studies were required. Aim: The study was designed to assess the capaciousness of damage caused by prolonged exposure of dinotefuran in mammals and probable strategy to neutralize its effect. Methodology: Ninety-day trial using Wistar rats (n=45) was conducted while dividing them into three groups: untreated control group, insecticide (dinotefuran) treated group, and dinotefuran treated and vitamin E supplemented group. Dinotefuran was administrated orally (LD25). Vitamin E (alpha-tocopherol) supplementation was given in water ad libitum. Blood sampling was done twice a month, and hematological and biochemical data were recorded. After expiry of trial period, the experimental rats were anesthetized and sacrificed. Organs (kidneys, liver, and heart) were isolated from each groups, weighed, and stored at approximately -20°C till further processing, analysis and histopathology were performed. Results: All the hematological parameters were affected significantly. Histopathology of tissues showed clear necrosis in all the tissues except kidneys. All the biomarkers of oxidative stress and comet assay demonstrated significant cell damage. All the parameters showed improvement after vitamin E supplementation but non-significantly. Significance: These findings were suggestive that even low dose persistent exposure can lead to mutagenicity and carcinogenicity in mammals and other non-target species hence revised policy guidelines and more intelligent use of these chemicals is required.

scholarly journals Perubahan morfologi sel HeLa setelah paparan ekstrak etanolik Curcuma longa

2017 ◽  
Vol 2 (1) ◽  
pp. 1 ◽  
Author(s):  
Suryani Hutomo ◽  
Heni Susilowati ◽  
Yanti Ivana Suryanto ◽  
Chandra Kurniawan
Keyword(s):  
Hela Cells ◽  
Apoptotic Cell ◽  
Morphological Changes ◽  
Cell Damage ◽  
Curcuma Longa ◽  
Positive Control ◽  
Cell Shrinkage ◽  
Treatment Groups ◽  
Significant Difference ◽  
Almost All

Cell morphological changes on HeLa cells after Curcuma longa etanolik extract exposure. Curcuma is mostly found in the areas with tropical and sub-tropical climate, and is one of original plants of Southeast Asia. In Indonesia, curcuma can be found in almost all regions and areas. Curcumin, which is curcuma’s main constituent, is a potent anti oxidant. Previous studies reported that curcuma longa extract may decrease the growth of cancer cells by interfering with cell proliferation, and by causing the cell apoptosis; however, the mechanism of apoptosis remains unclear. The purpose of this study was to investigate the effect of Curcuma longa extract on the morphological change of HeLa cells, indicating the cell damage. HeLa cells (5x10⁴ cells/well) were cultured in complete RPMI 1640 overnight before stimulation. Etanol extract of Curcuma longa (50 µg/ml, 100 µg/ml, 150 µg/ml) were added to the culture of HeLa cells and were incubated for 24 hours in antibiotic-free of culture medium. HeLa cells morphological analysis was performed under phase contrast microscope after haematoxilent eosin staining. Docsorubisin (0,5625 mg/ml) was used as positive control in this study. The results demonstrated that Curcuma longa extract caused cell morphological changes on HeLa cells indicated by cell shrinkage, lost contact with neighboring cells as the alteration of apoptotic cell death in most of cell population. The nuclei were dark as a result of their capability to absorb haematoxylene dye. Statistical analysis showed a significant difference between controls and treatment groups. It was then concluded that Curcuma longa extract induced cell damage on HeLa cells in a way of cell shrinkage.ABSTRAKKunyit (Curcuma longa) merupakan tanaman yang dapat tumbuh di daerah tropis dan sub tropis, serta merupakan tanaman asli Asia Tenggara. Di Indonesia, kunyit menyebar secara merata di seluruh daerah. Kurkumin yang merupakan unsur utama kunyit, merupakan antioksidan yang kuat. Beberapa penelitian juga menunjukkan bahwa kunyit mampu menghambat pertumbuhan beberapa tipe sel kanker. Mekanisme anti-kanker kurkumin adalah dengan menghambat proliferasi sel. Penelitian terdahulu melaporkan bahwa ekstrak Curcuma longa menginduksi apoptosis pada sel HeLa, tetapi mekanisme kematian sel tersebut belum jelas. Tujuan penelitian ini adalah untuk mengkaji pengaruh ekstrak Curcuma longa pada perubahan morfologi sel HeLa, dimana perubahan morfologi merupakan parameter kerusakan sel. Sel HeLa (5x104 sel/well) dikultur dalam RPMI 1640 semalam sebelum stimulasi. Ekstrak etanol kunyit (50 µg/ml, 100 µg/ml, 150 µg/ml) ditambahkan pada kultur HeLa dan diinkubasi selama 24 jam dalam medium tanpa antibiotik. Analisis morfologi sel HeLa dilakukan dengan menggunakan mikroskop fase kontras setelah pewarnaan haematoksilen eosin. Doksorubisin (0,5625 µg/ml) digunakan sebagai kontrol positif induksi apoptosis. Hasil penelitian menunjukkan bahwa ekstrak Curcuma longa menyebabkan perubahan morfologi sel yang ditandai dengan semakin mengecilnya ukuran sel, hilangnya prosesus sitoplasmik sehingga sel berbentuk bulat, serta hilang kontak dengan sel lain yang merupakan ciri apoptosis pada sebagian besar sel HeLa. Nukleus tampak berwarna gelap karena peningkatan kapasitas penyerapan zat haematoksilen. Analisa statistik menunjukkan perbedaan yang bermakna antara kelompok kontrol positif dan negatif dengan kelompok stimulasi dalam jumlah sel yang mengalami perubahan morfologi menuju apoptosis. Disimpulkan bahwa ekstrak Curcuma longa mampu menginduksi perubahan morfologi sel HeLa yaitu berupa cell shrinkage.

HOCl effects on the tight junctions of rabbit tracheal epithelium

1996 ◽  
Vol 270 (2) ◽  
pp. L224-L231 ◽  
Author(s):  
Y. Guo ◽  
M. Krumwiede ◽  
J. G. White ◽  
O. D. Wangensteen
Keyword(s):  
Tight Junction ◽  
Morphological Changes ◽  
Cell Damage ◽  
Freeze Fracture ◽  
Tracheal Epithelium ◽  
Epithelial Tissue ◽  
Laser Confocal Microscopy ◽  
Transmission Electron ◽  
Junction Protein ◽  
Before And After

We previously found that HOCl, produced from neutrophil products in infected airways, decreases electrical resistance (R) of rabbit tracheal epithelium. Interestingly, HOCl at 6 mM, a reasonable concentration in diseased airways, decreased R without apparent cell damage. This study sought to determine whether this noncytotoxic dose of HOCl causes morphological changes that correlate with the decrease in R. Excised rabbit tracheas were treated with 6 mM HOCl for 15 min, before and after which epithelial R was determined. Epithelial tissue was then fixed and prepared for transmission electron microscopy, immunofluorescent labeling of F-actin or the tight junction protein ZO-1, or freeze fracture to examine tight junction strands. HOCl treatment caused a 50% decrease in R. Electron micrographs showed no cell, cell membrane, or tight junction changes. By laser confocal microscopy, 6 mM HOCl did not affect the distribution of F-actin or ZO-1. However, morphometric analysis of freeze-fracture replicas showed that tight junction strand number was significantly decreased from 7.06 +/- 0.09 to 4.79 +/- 0.11 and junctional width was significantly decreased from 0.306 +/- 0.007 to 0.214 +/- 0.006 microns. These latter changes may have contributed to the observed decrease in epithelial R.

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