Negative Staining of F-Actin and Actin-Like Microfilaments using Tannic Acid

1976 ◽  
Vol 34 ◽  
pp. 324-325
Author(s):  
J.R. LaFountain ◽  
C.R. Zobel ◽  
H.R. Thomas ◽  
C. Galbreath
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Tannic Acid ◽  
Actin Filaments ◽  
Striated Muscle ◽  
Standard Technique ◽  
Muscle Cells ◽  
Negative Staining

Subsequent to its introduction a few years ago by Mizuhira and Fukaesaku (1) the practice of using tannic acid (TA) in glutaraldehyde (GA) fixatives followed by heavy metal postfixation has become a standard technique for revealing the substructure of microtubules. We showed in a previous report that a reaction similar to that between TA and tubulin also occurs between TA and actin. Actin filaments of striated muscle appear negatively stained in situafter GA-TA fixation and osmium postfixation (2). That result suggested that GA-TA fixatives might be applied to studies of actin-like filaments in non-muscle cells. However, in light of the results of Szamier et at(3) showing that naked (not protected by tropomyosin) F-actin is destroyed by osmium, it was questionable whether it was possible to preserve and negatively stain naked F-actin, as well as actin-like microfilaments, with GA-TA fixatives. Also, we did not know if osmium must be used as a postfixative or whether other heavy metals could be substituted for it.

Negative Staining of F-Actin in situ with Tannic Acid

1975 ◽  
Vol 33 ◽  
pp. 628-629
Author(s):  
James R. LaFountain ◽  
Herbert R. Thomas
Keyword(s):  
Electron Microscopy ◽  
Tannic Acid ◽  
Actin Filaments ◽  
Striated Muscle ◽  
Vastus Lateralis ◽  
Muscle Cells ◽  
Cacodylate Buffer ◽  
Spindle Apparatus ◽  
Ultrastructural Findings

Since the introduction of tannic acid as an additive in glutaraldehyde fixatives for electron microscopy, there have been numerous reports of ultrastructural findings that were not detectable after fixation without tannic acid. We have used tannic acid in studies on the spindle apparatus in insect spermatocytes to show that microtubules of the spindle are composed of 13 protofilaments. Tannic acid accumulates at the periphery of subunits of microtubules and with osmium stains those regions, leaving the subunits unstained. Hence, the subunits appear negatively stained.We have found that in addition to microtubules, other filamentous structures in cells appear negatively stained after fixation with glutaraldehyde-tannic acid. The most noteable are actin filaments in muscle cells. We report here results obtained from mouse striated muscle.Segments of gastrocnemius and vastus lateralis muscles are dissected in 3% glutaraldehyde in 0.1 M cacodylate buffer and subsequently fixed for 1 hr in the above fixative containing tannic acid (Mallinckrodt) in concentrations of 4 and 8%. Both concentrations gave similar results.

Removal of heavy metal from soil and groundwater by in-situ electrokinetic remediation

2000 ◽  
Vol 42 (7-8) ◽  
pp. 335-343 ◽  
Author(s):  
S. Shiba ◽  
S. Hino ◽  
Y. Hirata ◽  
T. Seno
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Electric Potential ◽  
Potential Gradient ◽  
Electrokinetic Remediation ◽  
Contaminated Aquifer ◽  
Physico Chemical ◽  
Operational Variables ◽  
Mass Transport Process

The operational variables of electrokinetic remediation have not been cleared yet, because this method is relatively new and is an innovative technique in the aquifer remediation. In order to investigate the operational variables of the electrokinetic remediation, a mathematical model has been constructed based on the physico chemical mass transport process of heavy metals in pore water of contaminated aquifer. The transport of the heavy metals is driven not only by the hydraulic flow due to the injection of the purge water but also by the electromigration due to the application of the electric potential gradient. The electric potential between anode and cathode is the important operational variable for the electrokinetic remediation. From the numerical simulations with use of this model it is confirmed that the remediation starts from the up stream anode and gradually the heavy metal is transported to the down stream cathode and drawn out through the purge water.

Assessing Soil and Plant Pollution by Abandoned Rural Waste Dumping Sites in Ningbo, China

2011 ◽  
Vol 138-139 ◽  
pp. 1149-1155 ◽  
Author(s):  
Yi Dong Guan ◽  
Ye Hong Du ◽  
Zhen Dong Li ◽  
An Cheng Luo
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Reference Value ◽  
Dry Weight ◽  
Rice Grain ◽  
Contamination Assessment ◽  
Plant Parts ◽  
Metal Contents ◽  
Plant Pollution

This paper reports the concentration of heavy metals (Cr, Cu, Zn, Cd and Pb) in the soils and rices surrounding the abandoned rural waste dumping sites in Ningbo. Igeo (geoaccumulation index) was calculated to assess the contamination degree of heavy metals in soils. The mean contents of Cr, Cu, Cd, Zn and Pb of soils were 33.3, 24.1, 1.5, 118.9 and 45.6 mg/(kg DW) (dry weight), respectively. All of them were much higher than that of the reference value (i.e. CK), but there were no coherent trend of the metal contents within 1-120m distance from the dumping site. Igeo of heavy metals reveals the order of Cd>Cu>Cr>Pb>Zn, and the contamination assessment of soils using Igeo indicate the moderate Cd pollution, while the soils were unpolluted-moderately overall by Cr, Cu, Zn as well as Pb. The heavy metal contents in root, stem & leaf and rice grains were all remarkable higher than that of the CK at 20-120 m distances, and the heavy metal contents in root were evidently much higher than other plant parts, while those in rice grain were lowest, indicating the great bioaccumulation trend of heavy metals. Although the metal contents in the rice grain were within the legislation limit, its bioaccumulation trend of heavy metals was remarkable, whose contents were 4.38-fold for Cr, 1.76-fold for Cu, 1.28-fold for Zn, 2.67-fold for Cd and 3.03-fold for Pb higher than that of reference value, respectively. Finally, we proposed a decentralized in-situ restoration approach for the dumping sites.

scholarly journals Heavy Metal Polluted Soils: Effect on Plants and Bioremediation Methods

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
G. U. Chibuike ◽  
S. C. Obiora
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Growth Performance ◽  
Anthropogenic Activities ◽  
Polluted Soils

Soils polluted with heavy metals have become common across the globe due to increase in geologic and anthropogenic activities. Plants growing on these soils show a reduction in growth, performance, and yield. Bioremediation is an effective method of treating heavy metal polluted soils. It is a widely accepted method that is mostly carried outin situ; hence it is suitable for the establishment/reestablishment of crops on treated soils. Microorganisms and plants employ different mechanisms for the bioremediation of polluted soils. Using plants for the treatment of polluted soils is a more common approach in the bioremediation of heavy metal polluted soils. Combining both microorganisms and plants is an approach to bioremediation that ensures a more efficient clean-up of heavy metal polluted soils. However, success of this approach largely depends on the species of organisms involved in the process.

scholarly journals Fungal-bacterial biofilm mediated heavy metal rhizo-remediation

2021 ◽  
Author(s):  
Amila Henagamage ◽  
C.M Peries ◽  
G. Seneviratne
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Removal ◽  
Bacterial Biofilm ◽  
Microbial Consortia ◽  
Tolerance Index ◽  
Chemical Fertilizers ◽  
Plant Toxicity ◽  
Microbial Biofilms

Abstract Heavy metal pollution due to excessive use of chemical fertilizers (CF) causes a major damage to the environment. Microbial consortia, closely associated with the rhizosphere are able to remediate heavy metal-contaminated soil by reducing plant toxicity. Thus, this study was undertaken to examine the remedial effects of microbial biofilms against contaminated heavy metals. Fungi and bacteria isolated from soil were screened for their tolerance against Cd2+, Pb2+ and Zn2+. Fungal-bacterial biofilms (FBBs) were developed with the highest tolerant isolates and were further screened for their bioremediation capabilities against heavy metals. The best biofilm was evaluated for its rhizoremediation capability with different CF combinations using a pot experiment conducted under greenhouse conditions with potato. Three bacterial and two fungal isolates were selected to develop FBBs upon the tolerance index (TI) percentage. Significantly (P < 0.05) the highest metal removal percentage was observed in Trichoderma harzianum and Bacillus subtilis biofilm under in situ condition. The biofilm with 50% of recommended CF (50CB) significantly (P < 0.05) reduced the soil available Pb2+ by 77%, Cd2+ by 78% and Zn2+ by 62% compared to 100% recommended CF (100C). In comparison to initial soil, it was 73%, 76% and 57% lower of Pb2+, Cd2+ and Zn2+, respectively. In addition, 50CB treatment significantly (P < 0.05) reduced the metal penetration into the tuber tissues in comparison with 100C. Thus, it is concluded that T. harzianum–B. subtilis biofilm is an ideal combination to remediate soil contaminated with Cd2+, Pb2+ and Zn2+.

Heavy Metals in the Water Column of Iloilo- Guimaras Jetty Port (Parola Wharf )

2013 ◽  
Vol 6 (1) ◽  
Author(s):  
BRIAN GIL S. SARINAS ◽  
LORNA D. GELLADA ◽  
MELCHOR M. MAGRAMO ◽  
MARLON R. TERUÑEZ
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Water Column ◽  
Physicochemical Parameters ◽  
Bottom Layer ◽  
Sampling Area ◽  
The Public ◽  
Ph Values ◽  
Seawater Samples

Jetty Port (Parola Wharf) in Iloilo City is a depot of passengers going toGuimaras, Philippines. Considering the dearth of studies on the presence of heavymetals in this area, this study was conducted. It aimed to determine the presenceand quantities of available heavy metals specifically lead, cadmium and chromiumin the water column (surface, middle and bottom) of Iloilo-Guimaras Jetty Port. Inaddition, water physicochemical parameters were also measured such as pH, salinityand temperature, in situ. Three sampling areas were identified in the Jetty Port.One liter was collected in the surface, middle and bottom layer of each sampling area for a total of nine seawater samples. The seawater samples were immediatelytransported to the CAS-Analytical Service Laboratory of UPV, Miag-ao, Iloilofor the quantification of available heavy metals through flame atomic absorptionspectrophotometric (FAAS) method. Ph values range from 6.0-7.333, 12.0-13.167ppm for salinity and 27.333-27.567 0C for three sampling areas. Average cadmium,chromium and lead were higher at station 3 with 0.69 mg/L, 0.81 mg/L and 0.339mg/L, respectively. The results showed that mean of Cr > Pb > Cd < Cr in the watercolumn of the three sampling areas, however is not significant, p>.05. Availablecadmium, chromium and lead exceeded the permissive value. This study will giveinformation to the public about the present heavy metal status of the Jetty Port.

IN-SITU DETECTION OF HEAVY METAL POLLUTION IN SEAWATER WITH DIAMOND COATED ELECTRODES

2019 ◽  
Vol 26 (04) ◽  
pp. 1850179
Author(s):  
BIN ZHAO ◽  
JIA LI ◽  
XIANG YU ◽  
JING ZHANG ◽  
YI REN
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Pollution ◽  
Heavy Metal Pollution ◽  
Mercury Electrode ◽  
In Situ Monitoring ◽  
National Standard ◽  
Electrochemical Window ◽  
Multiple Heavy Metals

Heavy metal pollution endangers seawater and there is urgent need for the development of effective detectors that can provide warning of heavy metal pollution. Anodic stripping voltammetry is applicable for the detection of heavy metal pollution in sea water, but it suffers from two problems that are associated with the mercury electrode used: one is insufficient sensitivity and the other is secondary pollution caused by toxic mercury. In this work, we employed boron-doped diamond electrode as an alternative to mercury electrode for the detection of heavy metals. The BDD electrode was fabricated and its electrochemical properties were ascertained. The results of this work showed that: (1) the electrode prepared has a wide electrochemical window (4.2 V) and low background current ([Formula: see text]A). (2) multiple heavy metals (Pb[Formula: see text], Cd[Formula: see text], Zn[Formula: see text] and Cu[Formula: see text]) in seawater samples are detected simultaneously with the optimized electrode, with high sensitivity and good repeatability. (3) the repeatability of the detection meets the values stipulated in the national standard. The detection period is less than 15[Formula: see text]min, and in situ monitoring of heavy metals in seawater can be achieved by automatic sampling and wireless data transmission.

scholarly journals Romanian bentonite and fly ash characterization and their use in heavy metal “in-situ” immobilization in polluted soils

2017 ◽  
Vol 18 ◽  
pp. 01022
Author(s):  
Săndica Liliana Gherghe ◽  
Ildiko Anger ◽  
Georgiana Moise ◽  
Roxana Trusca
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Fly Ash ◽  
Contact Time ◽  
In Situ Immobilization ◽  
Polluted Soils ◽  
Ft Ir ◽  
Metallurgical Activities

This article presents the characterization of the Romanian bentonite and fly ash, using different techniques: FAAS, XRD, FT-IR, SEM and EDAX and their evaluation as sorbents for heavy metals immobilization in polluted soils coming from mining and metallurgical activities. The applicability of bentonite and fly ash for Pb (II) and Zn (II) immobilization was studied using aqueous solutions of these metals. The influence of the pH and contact time were studied. The results shown that the Romanian bentonite and fly ash could be used for Pb (II) and Zn (II) immobilization in polluted soils from brownfields.

Temporal Variations in Heavy Metal Partitioning and Loading in Urban Highway Pavement Sheet Flow: Implications for In Situ Treatment Design

2000 ◽  
Vol 1720 (1) ◽  
pp. 100-111 ◽  
Author(s):  
John J. Sansalone ◽  
Donald W. Glenn
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Best Management Practices ◽  
Storm Water ◽  
Water Runoff ◽  
Rainfall Runoff ◽  
Metal Partitioning ◽  
Sheet Flow ◽  
Treatment Design

In situ treatment design for pavement storm water runoff continues to pose unique challenges because of the unsteady nature of processes such as rainfall runoff, mobilization, partitioning, and delivery of heavy metals. Storm water from pavements and roadways transports dissolved, colloidal, and suspended solids in a heterogeneous mixture, and along with pH, alkalinity, traffic levels, and residence time, influences the partitioning of heavy metals. For effective in situ treatment design, an understanding of heavy metal partitioning and temporal wash-off during a rainfall runoff event is a prerequisite. This study investigates zinc (Zn), cadmium (Cd), copper (Cu), and lead (Pb) partitioning, cumulative loadings, and wash-off in storm water pavement sheet flow from a heavily traveled urban interstate pavement site. Results are presented for a series of eight rainfall runoff events at the instrumented site. Results from partitioning analysis (heavy metal mass transfer) between the dissolved and particulate-bound fractions indicate that Zn, Cd, and Cu masses are predominately dissolved in pavement sheet flow, qsf. Although a relatively insoluble heavy metal, Pb mass was also mostly dissolved. These high dissolved fractions can be attributed to low urban rainfall pH levels, relatively short pavement residence times for the qsf, and low pavement runoff alkalinity. Plots of cumulative heavy metal mass as a function of elapsed runoff time clearly demonstrate that during all events the qsf dissolved fractions dominated the particulate fractions for Zn, Cd, Cu, and Pb. As far as delivery, results also indicate that the dissolved masses for Zn, Cd, Cu, and Pb generally exhibited a “first flush” compared with their particulate masses. The design of in situ treatment systems or source control best management practices loaded by qsf require data on partitioning and loading for effective treatment.

scholarly journals Advances in Heavy Metal Bioremediation: An Overview

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Ali Sayqal ◽  
Omar B. Ahmed
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Heavy Metal Contamination ◽  
Ex Situ ◽  
Toxic Heavy Metals ◽  
Heavy Metal Remediation ◽  
Land Farming ◽  
Biological Methods ◽  
Metal Bioremediation

The pollution of toxic heavy metals is considered one of the most important environmental issues which has accelerated dramatically due to changing industrial activities. This review focuses on the most common methods, strategies, and biological approaches of heavy metal bioremediation. Also, it provides a general overview of the role of microorganisms in the bioremediation of heavy metals in polluted environments. Advanced methods of heavy metal remediation include physicochemical and biological methods; the latter can be further classified into in situ and ex situ bioremediation. The in situ process includes bioventing, biosparging, biostimulation, bioaugmentation, and phytoremediation. Ex situ bioremediation includes land farming, composting, biopiles, and bioreactors. Bioremediation uses naturally occurring microorganisms such as Pseudomonas, Sphingomonas, Rhodococcus, Alcaligenes, and Mycobacterium. Generally, bioremediation is of very less effort, less labor intensive, cheap, ecofriendly, sustainable, and relatively easy to implement. Most of the disadvantages of bioremediation relate to the slowness and time-consumption; furthermore, the products of biodegradation sometimes become more toxic than the original compound. The performance evaluation of bioremediation might be difficult as it has no acceptable endpoint. There is a need for further studies to develop bioremediation technologies in order to find more biological solutions for bioremediation of heavy metal contamination from different environmental systems.

Sign in / Sign up

Export Citation Format

Share Document