scholarly journals Deactivation of Ascaris suum eggs using electroporation and sequential inactivation with chemical disinfection

2020 ◽  
Vol 10 (3) ◽  
pp. 558-568
Author(s):  
C. Niven ◽  
C. B. Parker ◽  
S. D. Wolter ◽  
M. H. Dryzer ◽  
C. B. Arena ◽  
...  
Keyword(s):  
Pulse Train ◽  
Ascaris Suum ◽  
Chemical Exposure ◽  
Alternative Technique ◽  
Buffer Solution ◽  
Helminth Eggs ◽  
Low Concentrations ◽  
Pass Through ◽  
Sequential Inactivation ◽  
Initial Results

Abstract Electroporation has been evaluated as a potential backend wastewater treatment for deactivation of Ascaris suum eggs in buffer solution. Initial results indicate that eggshell permeability is affected by the pulse train electric field strength and duration. Coupling electroporation with chemical exposure, using low concentrations of commercially available disinfectants, allows oxidizing agents to pass through the complex strata of the A. suum eggshell, specifically reaching the innermost embryonic environment, which leads to successful deactivation compared to either method used separately. The aim of this work is to identify and develop an alternative technique that efficiently inactivates helminth eggs present in wastewater.

scholarly journals Siphon-Induced Droplet Break-Off for Enhanced Mixing on a Centrifugal Platform

Inventions ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 1 ◽  
Author(s):  
Robert Burger ◽  
David J Kinahan ◽  
Hélène Cayron ◽  
Nuno Reis ◽  
João Fonseca ◽  
...  
Keyword(s):  
Human Plasma ◽  
Spectroscopic Method ◽  
Colorimetric Method ◽  
Phosphate Buffer Solution ◽  
Potassium Thiocyanate ◽  
Single Step ◽  
Buffer Solution ◽  
Batch Mode ◽  
Two Fluids ◽  
Pass Through

We present a powerful and compact batch-mode mixing and dilution technique for centrifugal microfluidic platforms. Siphon structures are designed to discretize continuous flows into a sequence of droplets of volumes as low as 100 nL. Using a passive, self-regulating 4-step mechanism, discrete volumes of two fluids are alternatingly issued into a common intermediate chamber. At its base, a capillary valve acts as a fluidic shift register; a single droplet is held in place while two or more droplets merge and pass through the capillary stop. These merged droplets are advectively mixed as they pass through the capillary valve and into the receiving chamber. Mixing is demonstrated for various combinations of liquids such as aqueous solutions as well as saline solutions and human plasma. The mixing quality is assessed on a quantitative scale by using a colorimetric method based on the mixing of potassium thiocyanate and iron(III) chloride, and in the case of human plasma using a spectroscopic method. For instance, volumes of 5 µL have been mixed in less than 20 s. Single-step dilutions up to 1:5 of plasma in a standard phosphate buffer solution are also demonstrated. This work describes the preliminary development of the mixing method which has since been integrated into a commercially available microfluidic cartridge.

Ozonation by-products issued from the destruction of microorganisms present in wastewaters treated for reuse

2004 ◽  
Vol 50 (2) ◽  
pp. 187-193 ◽  
Author(s):  
M.N. Rojas-Valencia ◽  
M.T. Orta-de-Velásquez ◽  
M. Vaca-Mier ◽  
V. Franco
Keyword(s):  
Amino Acids ◽  
Ascaris Suum ◽  
Correlation Coefficients ◽  
Salmonella Typhi ◽  
Faecal Coliforms ◽  
Excellent Correlation ◽  
Low Concentrations ◽  
Micro Organisms ◽  
By Products ◽  
Cellular Lysis

This work demonstrates the reaction of ozone on the amino acids comprising the covering layer of resistant micro-organisms. A secondary aim was to check the byproducts generated when ozone was applied to synthetic samples (such as Vibrio cholerae NO 01 WFCC-449, Salmonella typhi ATTC-6539, faecal coliforms and Ascaris suum). The ozone was applied at a concentration of 18.4 mgO3/min at pH 3, for different lengths of time. In the case of bacteria, results showed that, at 8 minutes, the number was reduced to the level of the Official Mexican Standards set for treated water destined for irrigation purposes (1,000 MPN/100 mL). Excellent correlation coefficients (0.95 to 0.99) were obtained for microbial concentrations versus ozone contact time. Destruction times required for 100% removal of the initial bacteria population varied between 2 and 14 minutes, while Ascaris suum required 1 hour. When Gram-negative bacteria die due to the effects of ozone, cellular lysis and the liberation of endotoxins (biodegradable) were observed. The ozonation of amino acids in the shell of Ascaris suum eggs, leads to the formation of aldehydes, such as formaldehyde and acetaldehyde, in low concentrations (0.0003 and 0.0005 μg/mL respectively). These levels are not hazardous to human health.

scholarly journals Inhibition of fly head acetylcholinesterase by bis-[(m-hydroxyphenyl)trimethylammonium iodide] esters of polymethylenedicarbamic acids

1970 ◽  
Vol 117 (2) ◽  
pp. 221-230 ◽  
Author(s):  
J. H. Davies ◽  
W. R. Campbell ◽  
C. W. Kearns
Keyword(s):  
Functional Group ◽  
Straight Chain ◽  
Experimental Conditions ◽  
Maximum Slope ◽  
Large Molecules ◽  
High Affinity ◽  
Affinity Constants ◽  
Low Concentrations ◽  
High Concentrations ◽  
Pass Through

A series of bis-[(m-hydroxyphenyl)trimethylammonium iodide] esters of polymethylenedicarbamic acids and a number of (m-hydroxyphenyl)trimethylammonium iodide esters of straight-chain N-alkylcarbamic acids have been examined as inhibitors of acetylcholinesterase from fly head. Evidence is presented suggesting that inhibition of acetylcholinesterase by the bis-carbamates is due to carbamoylation of the enzyme, as is generally thought to be the case with esters of N-alkylcarbamic acids. Inhibition is irreversible. The (m-hydroxyphenyl)trimethylammonium iodide ester of N-hexylcarbamic acid also inhibits fly head acetylcholinesterase irreversibly. There is therefore no need to implicate a second functional group in bis-carbamate esters to explain the irreversible inhibition of the enzyme. An unusual feature of the inhibition is that inhibition lines do not pass through 100% enzyme activity at t=0, except for rather low concentrations of inhibitor (<10μm for the octamethylene compound). Also, inhibition lines tend towards a maximum slope as inhibitor concentration is increased. The first observation indicates complex-formation, even in the presence of high concentrations of substrate, and by using measurements of inhibition at relatively high inhibitor concentrations, affinity constants K′a have been calculated. K′a varies from 0.1μm for the dodecamethylene compound to 10μm for the tetramethylene compound, in the presence of 3.75mm-acetylthiocholine, indicating high affinity for the enzyme. The second observation shows that, owing to this high affinity, the enzyme becomes saturated with inhibitor under the experimental conditions employed, and from the limiting slope values of the carbamoylation rate constant (k2) have been calculated. k2 varies from 0.15min−1 for the tetramethylene compound to 1min−1 for the decamethylene compound. Variations of potency in this series are therefore mainly due to changes in affinity (100-fold) rather than in carbamoylation rate (sevenfold). The observation that large molecules may acylate the enzyme raises certain problems, which are discussed.

Viability of Ascaris suum eggs in stored raw and separated liquid slurry

Parasitology ◽  
2012 ◽  
Vol 140 (3) ◽  
pp. 378-384 ◽  
Author(s):  
KIRAN KUMAR KATAKAM ◽  
ALLAN ROEPSTORFF ◽  
OLGA POPOVIC ◽  
NIELS C. KYVSGAARD ◽  
STIG MILAN THAMSBORG ◽  
...  
Keyword(s):  
Ascaris Suum ◽  
Fecal Pollution ◽  
Pig Slurry ◽  
Egg Viability ◽  
Initial Analysis ◽  
Helminth Eggs ◽  
High Ammonia ◽  
Pathogen Survival ◽  
Liquid Slurry

SUMMARYSeparation of pig slurry into solid and liquid fractions is gaining importance as a way to manage increasing volumes of slurry. In contrast to solid manure and slurry, little is known about pathogen survival in separated liquid slurry. The viability of Ascaris suum eggs, a conservative indicator of fecal pollution, and its association with ammonia was investigated in separated liquid slurry in comparison with raw slurry. For this purpose nylon bags with 6000 eggs each were placed in 1 litre bottles containing one of the two fractions for 308 days at 5 °C or 25 °C. Initial analysis of helminth eggs in the separated liquid slurry revealed 47 Ascaris eggs per gramme. At 25 °C, egg viability declined to zero with a similar trend in both raw slurry and the separated liquid slurry by day 308, a time when at 5 °C 88% and 42% of the eggs were still viable in separated liquid slurry and raw slurry, respectively. The poorer survival at 25 °C was correlated with high ammonia contents in the range of 7·9–22·4 mm in raw slurry and 7·3–23·2 mm in liquid slurry compared to 3·2–9·5 mm in raw slurry and 2·6–9·5 mm in liquid slurry stored at 5 °C. The study demonstrates that at 5 °C, A. suum eggs have a higher viability in separated liquid slurry as compared to raw slurry. The hygiene aspect of this needs to be further investigated when separated liquid slurry is used to fertilize pastures or crops.

scholarly journals Analysis of Emission Infrared Spectra of Protein Solutions in Low Concentrations

2020 ◽  
Vol 8 ◽  
Author(s):  
Nikita Penkov ◽  
Nadezda Penkova
Keyword(s):  
Emission Spectra ◽  
Infrared Emission ◽  
Water Control ◽  
Three Solutions ◽  
Buffer Solution ◽  
Radiation Level ◽  
Low Concentration ◽  
Spectral Bands ◽  
Distant Effect ◽  
Low Concentrations

In this work, based on the method of infrared emission spectroscopy, the study of emission spectra of interferon-gamma (IFNγ) solution in a mixture or surrounded by three low-concentration solutions (IFNγ, antibodies to IFNγ, glycine buffer) or water control was performed. First of all, the solutions of low concentrations themselves were studied. It was shown that low-concentration solutions of IFNγ and antibodies to IFNγ had lower emission intensity in three spectral bands near 800, 1,300 and 2000 cm−1 compared to water control. Glycine buffer solution had a radiation level indistinguishable from that of the control. In this work, the effect of adding these low-concentration solutions to IFNγ (1 mg/ml) was compared to the effect of adding water control to IFNγ. All solutions or water were added in 10% (v/v). It was found that adding each of the three test solutions induced an increase in the radiation intensity of the IFNγ solution in the spectral range of 400–1700 cm−1 (compared to the IFNγ solution with control spike). It was also tested whether the radiation of the studied low-concentration solutions surrounding the IFNγ solution (1 mg/ml) affected the IFNγ radiation. The measurement results were compared to the data obtained for IFNγ surrounded by water control. All three solutions were found to exert a distant effect on the IFNγ solution (1 mg/ml), which was manifested in a decrease in the intensity of its radiation near 1,000 and 1,500 cm−1 compared to the control solution of IFNγ. Thus, the emission spectra of low-concentration aqueous solutions were measured for the first time, and differences in the emission spectra of the IFNγ solution depending on low-concentration additives and the environment were shown. The paper interprets the observed differences and discusses possible mechanisms underlying the observed phenomena.

Effect of post-treatment conditions on the inactivation of helminth eggs (Ascaris suum) after the composting process

2015 ◽  
Vol 37 (8) ◽  
pp. 920-928 ◽  
Author(s):  
Hamidatu S. Darimani ◽  
Ryusei Ito ◽  
Ynoussa Maiga ◽  
Mariam Sou ◽  
Naoyuki Funamizu ◽  
...  
Keyword(s):  
Ascaris Suum ◽  
Post Treatment ◽  
Composting Process ◽  
Helminth Eggs ◽  
Treatment Conditions

Contrast Medium-Induced Vasoconstrictions

1995 ◽  
Vol 36 (2) ◽  
pp. 198-203 ◽  
Author(s):  
J. Karstoft ◽  
L. Bååth ◽  
I. Jansen ◽  
L. Edvinsson
Keyword(s):  
Smooth Muscle ◽  
Calcium Antagonist ◽  
Contrast Media ◽  
Contrast Medium ◽  
Vessel Wall ◽  
Nerve Terminals ◽  
Buffer Solution ◽  
Low Concentrations ◽  
Isolated Arteries

Angiographic contrast media (CM) may cause both vasodilatation and vasoconstriction. This study evaluates a contrast medium-induced vasoconstriction that occurs when isolated arteries are exposed directly to a CM. Segments of rabbit coronary arteries were mounted in tissue baths containing buffer solution. During the experiments the buffer solution was exchanged with iohexol iso-osmolar with plasma, which caused a temporary vasoconstriction of the vessel segments. The constriction did not depend on the degree of oxygenation of iohexol. The endothelium was not involved in the vasoconstriction. Prazosin slightly decreased the vasoconstriction and a small part of the constriction might thus depend on liberation of norepinephrine by iohexol. The constriction was totally inhibited by the calcium antagonist nifedipine, while it was augmented by addition of low concentrations of KCl to ihoexol. It is concluded that the otherwise safe CM iohexol causes vasoconstriction in vitro by depolarizing the smooth muscle cells and the nerve terminals in the vessel wall.

Investigating helminth eggs and Salmonella sp. in stabilization ponds treating septage

2005 ◽  
Vol 51 (12) ◽  
pp. 239-247 ◽  
Author(s):  
G.S. Sanguinetti ◽  
C. Tortul ◽  
M.C. García ◽  
V. Ferrer ◽  
A. Montangero ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Analytical Method ◽  
Salmonella Enteritidis ◽  
Storage Time ◽  
Initial Concentration ◽  
Native Flora ◽  
Sludge Disposal ◽  
Helminth Eggs ◽  
Low Concentrations ◽  
Salmonella Survival

Sludge management arises as a relevant problem after being accumulated in primary ponds of septage treatment plants. One of the most attractive options for sludge disposal is its use in agriculture and then specific guidelines regarding hygienic quality must be fulfilled. This study aimed at evaluating the storage time needed to inactivate Ascaris eggs and Salmonella in sludge accumulated in a primary pond treating septage. Raw septage exhibited very low concentrations of viable Ascaris eggs, thus experiments with Ascaris suum eggs spiking were conducted. The concentration of Ascaris eggs in the solids accumulated at the bottom of the pond was 20 eggs/g of total solids (g TS) at the time of pond closure. Although it decreased, some eggs remained viable (0.59 mean viable eggs/g TS) up to 20 months of in-pond storage of the biosolids. Salmonella survival was studied after developing an analytical method that inhibited the native flora. Sludge was seeded with Salmonella enteritidis. An equation adequately describing Salmonella die-off in biosolids subjected to 115 days of in-pond storage/dewatering, was found to be represented by the regression: y = log MPN Salmonella/g TS = 6.67·t−0.086, with t= storage time elapsed in days. The initial concentration was 7.0 × 106 MPN/g TS and the removal efficiency was 99 %.

scholarly journals Measuring Ciliary Neurotrophic Factor (CNTF) in Lacrimal Fluid Using Optimized Commercial ELISA

2018 ◽  
Vol 1 (4) ◽  
pp. e00079 ◽  
Author(s):  
T.A. Druzhkova ◽  
A.A. Shpak ◽  
K.I. Kozlova ◽  
A.A. Yakovlev ◽  
A.B. Guekht ◽  
...  
Keyword(s):  
Neurotrophic Factor ◽  
Sandwich Elisa ◽  
Phosphate Buffer Solution ◽  
Ciliary Neurotrophic Factor ◽  
Buffer Solution ◽  
Lacrimal Fluid ◽  
Standard Curve ◽  
Low Concentrations ◽  
Detectable Concentration ◽  
Commercial Kits

The concentration of ciliary neurotrophic factor (CNTF) was measured in lacrimal fluid (LF) using Human CNTF Quantikine ELISA kit (“R&D Systems”, USA) on a ChemWell 2910 automatic analyzer (“Awareness Technology Inc.”, USA). We initially attempted to use commercial kits, designed for serum and plasma CNTF detection, to quantify lacrimal CNTF. The results, however, were rarely above the minimum detection level of the kits, most likely due to matrix complexity and low concentrations of CNTF in diluted LF (LF had to be diluted because of the small volume of collected samples). The optimal sensitivity and the lowest background for the best minimum quantifiable value were determined empirically. Phosphate buffer solution containing 1% bovine serum albumin was selected as an optimal diluent for CNTF measurements in small fluid samples. A standard curve was produced using the calibrating solutions 0-250 pg/ml. Acid treatment of LF samples before the analysis allowed to increase the detectable concentration of the CNTF two-fold. The 1:3 dilution was selected based on the available volume of collected LF and a reasonable variation coefficient. The described protocol allowed to develop a sandwich ELISA optimized for lacrimal CNTF.

scholarly journals Prevalence of Swine Nematodes in Moscow, Russia

2021 ◽  
Vol 14 (4) ◽  
pp. 1463-1467
Author(s):  
Igor G. Glamazdin
Keyword(s):  
Comparative Analysis ◽  
Detailed Analysis ◽  
Ascaris Suum ◽  
Moscow Region ◽  
Helminth Eggs ◽  
Current Prevalence ◽  
Prophylactic Measures

To continue the fight against pig helminthiasis, a detailed analysis of the current prevalence of nematodes in these productive animals is required. The assessment of the material after the technological slaughter of pigs kept in the Moscow region revealed the presence of parasitization in their intestines of four nematodes (Ascaris suum, Metastrongylus spp., Trichocephalus spp., Strongyloides spp.) In the form of monoinvasion and any combination thereof. The total infestation of pigs with intestinal nematodes was 55.24%. Trichocytic invasion (Trichocephalus spp.) Occurred in pigs most often (23.77%), ascarous invasion (Ascaris suum) reached 22.38%, strongyloid invasion (Strongyloides spp.) Was noted in 9.09% of cases, metastrongylous (Metastrongylus spp.) was present in 1.75% of cases. In conditions of an increase in the severity of monoinvasion, the size of helminth eggs decreased in Trichuris: size in length by 5.9%, size in width by 7.4%, in Ascaris: length by 4.9%, width by 4.6%, in strongulata eggs a decrease in size is also noted. In the case of mixed Ascaris-Metastrongylous invasion, there was a clear antagonistic relationship, manifested in a decrease in the size of Ascaris eggs. The size of the eggs of Trichuris in the case of an invasion mixed with Ascaris decreased, which is apparently associated with the development of antagonism between them. Comparative analysis of information on the prevalence of nematodes in pigs in farms of the Moscow region and their size can help to increase the effectiveness of treatment and prophylactic measures against helminthiasis, and can be taken into account in the course of further examination of pigs in the Moscow.

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