Injection Of Ferric Chloride Research Articles

Removal of emerging micropollutants from wastewater by activated carbon adsorption: Experimental study of different activated carbons and factors influencing the adsorption of micropollutants in wastewater

Activated carbon processes, initially designed for drinking water production, are tested for wastewater application in order to characterize their efficiency to remove micropollutants from wastewater treatment plants (WWTPs) discharges. In that purpose, a pilot was studied by the Paris sanitation service (SIAAP) and the water environment and urban systems laboratory (LEESU). The in-situ study raised several additional questions related to the structural and morphological properties of activated carbons, in order to select the proper material, the influence of operational parameters such as the activated carbon dose and the contact time, the role of organic matter concentration and composition, the presence of a residual concentration of methanol or the impact of ferric chloride addition. Thus, various complementary experiments were carried out at laboratory scale to improve the understanding of the micropollutants adsorption process on activated carbon, in particular on powdered activated carbon (PAC).The results have highlighted a strong link between the efficiency of PACs and their specific surface (BET), which can be easily estimated by their bulk density. The study of the sorption process has also confirmed the strong influence of the PAC dose and the rapidity of the sorption kinetic. From an operational point of view, the ferric chloride injection seems to slightly improve most of the detected compounds adsorption, probably thanks to the coagulation of the dissolved organic matter colloidal fraction. In contrary, the presence in the water of a residual concentration of methanol seems to have no impact on the micropollutant fate. The influence of the wastewater matrix is strong, with notably lower adsorption in water from primary settling compared to various WWTP discharges. However, the dissolved organic carbon concentration is not always sufficient to explain sorption competitions in wastewater, and the nature of the organic matter should be considered too. In particular, the carbon removal from biological treatments is the step that clearly modifies both the quantity and the composition of the organic matter. It has been observed that discharges from WWTPs operating with different biological processes (activated sludge, membrane bioreactor or biofiltration) have similar organic matter concentrations and compositions, and allows comparable removals of organic matter and micropollutants by adsorption. The lower performances on micropollutants observed in the settled water can be explained by the higher quantity of protein-like molecules (fluorophores Iδ and Iγ), which compose the most competitive organic matter fraction for adsorption on activated carbon, compared to the other waters.

Electrical Stimulation of the Substantia Nigra Pars Reticulata (SNr) Suppresses Chemically Induced Neocortical Seizures in Rats

Deep brain stimulation is an alternate treatment strategy for intractable epilepsy. The effects of low- and high-frequency electrical stimulation to the substantia nigra pars reticulata (SNr) of different sides on chemically induced neocortical seizure were investigated in the present study. After neocortical seizure was induced by ferric chloride injection into the left sensorimotor cortex, SNr was stimulated ipsilaterally, contralaterally, or bilaterally at frequencies of 130 or 20 Hz in rats. Unilateral and bilateral stimulation at 130 Hz reduced significantly the number of seizures but not their duration. Ipsilateral, contralateral as well as bilateral stimulations at 130 Hz were all equally effective, producing reductions in seizures of 63.62, 77.84, and 68.74% compared with the control group, respectively. Electrical stimulation at 20 Hz did not reduce the number or duration of seizures regardless of the side stimulated. Both unilateral and bilateral stimulations of SNr at 130 Hz can suppress ictogenesis in the cortex, but electrical stimulation at 130 or 20 Hz does not reduce the severity of individual seizures. The frequency of stimulation is paramount in suppressing neocortical seizures in which DBS at least targets SNr.

LIPID PEROXIDATION AFTER INTRACORTICAL INJECTION OF FERRIC CHLORIDE INCREASES THE INCIDENCE OF SEIZURES IN YOUNG RATS

Clinical studies have shown that the incidence of early posttraumatic seizures ishigher in children than in adults and it has been proposed that iron-induced lipidperoxidation has an important role in the development of epileptogenic foci. In this study,we examined some of the hypothesized reasons for the difference in the incidence ofearly posttraumatic seizures between young and adult rats. Twelve young and twelveadult rats were randomized into 4 groups. Group 1 and 2 were control groups, eachcomprising of 6 young rats and 6 adult rats respectively and were given intracorticalinjections of normal saline. Group 3 and 4 were injury groups, again comprising 6 youngrats and 6 adult rats respectively and were given intracortical injections of FeCl3. All ratswere observed for 6 hours post injection for the occurrence of seizures and were thenkilled. The injected hemispheres were extirpated and tested for malondialdehyde (MDA)level and superoxide dismutase (SOD) activity as indices of oxidative damage. Resultsshowed that seizures were observed only in Group 3. Increased MDA level and decreasedSOD activity were observed in Group 3 (ANOVA, p<0.001). Increased MDA levels anddecreased SOD activity were significantly higher in rats with seizures (Group 3) than inthose without seizures (independent t-test, p<0.001). We conclude was that differentlevels of lipid peroxidation induced by intracortical ferric chloride injection may accountfor the different seizure incidence between young and adult rats

Arterial Thrombosis in Mice with Factor V Leiden Mutation

The factor V Leiden (FVL) mutation has been demonstrated to be associated with the development of venous thrombosis in humans. Whether such a propensity also exists in the arterial circulation remains controversial. In an effort to minimize the variability that clouds the clinical study of arterial thrombosis, we studied FVL-associated arterial thrombosis in an experimental model of homozygous, heterozygous, and wild-type mice. Heterozygous FVL mice were crossbred to C57BL/6J mice over several generations. The genotypes of the resulting three genotype groups (wild type, heterozygous FVL, and homozygous FVL) were blinded to the investigators. Arterial injury was produced with the injection of ferric chloride into an isolated segment of carotid artery. Arterial thrombosis was assessed with an ultrasonic flow probe and the time to occlusion (TTO) was recorded. The carotid artery occluded within 60 minutes of injury in 72 of the animals studied (97.3%). The carotid artery remained patent at 60 minutes in the remaining two animals, both of whom were subsequently found to be genotypically wild type. There was a statistically significant relationship between TTO and genotype (p = .002). TTO was greatest in the wild-type mice (p < .001 vs heterozygous, < .001 vs homozygous) and least in the homozygotes (p < .001 vs heterozygotes). Increased thrombogenicity is present in mice with the FVL mutation and is more prolonged in homozygotes than heterozygotes. These findings provide some corroboration to the clinical studies that suggest an increased risk of arterial events in patients with the FVL mutation.

Lipoic acid pretreatment attenuates ferric chloride-induced seizures in the rat

Traumatic brain injury (TBI) is often complicated by the occurrence of seizures, which adversely affect clinical outcome. The risk of seizures increases to the extent that the injury is associated with sub-arachnoid hemorrhage and hematoma. A likely mechanism of seizure development post-TBI is decompartmentalization of iron from extravasated hemoglobin (Hb). It is well known that iron can catalyze formation of reactive oxygen species (ROS). Based on this proposed mechanism, a descriptive model of TBI-induced seizures, using intracortical injection of iron salts, was developed by Willmore. We have added modifications to enhance the quantifiability of seizure activity and have used the model to examine the therapeutic efficacy of lipoic acids (ROS-scavenging antioxidants). Male SD rats were pretreated with alpha-lipoic acid (ALA) and dihydrolipoic acid (DHLA) or appropriate vehicles. Under anesthesia, unilateral intracortical infusions of ferric choride were performed stereotaxically. EEG was recorded via extradural electrodes. EEG was sampled for 10 s of every 60-s interval over a 24-h period following injection of ferric chloride. We measured the number of seconds of epileptiform discharges or seizure activity in every 10-s EEG sample during the 24 h. The EEGs of rats pretreated with ALA and DHLA exhibited 55% less seizure activity than vehicle-treated ferric chloride-injected animals, suggesting that lipoic acids may be of use in preventing or attenuating TBI-induced seizures.

Zonisamide reduces the increase in 8-hydroxy-2'-deoxyguanosine levels formed during iron-induced epileptogenesis in the brains of rats.

To examine the change of 8-hydroxy-2'deoxyguanosine (8-OHdG) levels, which are used as a marker for oxidative DNA damage, in iron-induced epileptogenic foci of the rat cerebrum. Male Wistar rats were given a cortical injection of ferric chloride, and their 8-OHdG levels were determined over time. Additional animals were pretreated with the antiepileptic drug zonisamide (ZNS) before the ferric chloride injection, and their 8-OHdG levels were compared with the nonpretreated rats. Fifteen minutes after ferric chloride solution injection, the level of 8-OHdG increased, reaching a maximum 30 minutes after injection. Sixty minutes after injection, the levels coincided with those of controls. ZNS, in concentrations of 50 and 100 mg/kg body weight, prevented the increase of 8-OHdG levels within the cerebrum 30 minutes after iron solution injection. These results indicate that the formation of iron-induced epileptogenic foci in rats is related to DNA-damage-induced reactive oxygen species and that the inhibition of 8-OHdG formation by ZNS after iron injection may be due to the drug's antioxidant activity. The data suggest that free radical species known to be formed during iron salts-induced focal epileptogenesis cause damage to isocortical DNA. Furthermore, ZNS appears to inhibit the focal injuring response to DNA that occurs following iron salts-induced acute epileptogenesis.

Anticonvulsive and free radical scavenging activities of vanillyl alcohol in ferric chloride-induced epileptic seizures in Sprague-Dawley rats

Vanillyl alcohol (VA) is a component of Gastrodia elata Bl. (GE), which is a traditional Chinese herb widely used to treat convulsive disorders or dizziness. This study examined the role of VA in the anticonvulsive properties of GE in a Sprague-Dawley rat model of epilepsy. The anticonvulsive and free radical scavenging activities of VA were examined after intracortical injection of ferric chloride (100 mM, 8 l) to induce epileptic seizures. These seizures were verified by behavioral observations and electroencephalographic (EEG) and electromyographic (EMG) recordings. Ferric chloride injection resulted in increased lipid peroxide levels in the ipsilateral and contralateral cerebral cortex, and increased luminol-chemiluminescence (CL) and lucigenin-CL counts in the peripheral blood. Intraperitoneal injection (i.p.) of VA (200 mg/kg or 100 mg/kg) or phenytoin 10 mg/kg prior to ferric chloride administration significantly inhibited wet dog shakes (WDS) and lipid peroxide levels in the bilateral cerebral cortex. VA 200 mg/kg also significantly reduced luminol-CL and lucigenin-CL counts in the peripheral blood, but no significant effect was observed following administration of VA 100 mg/kg or phenytoin. These data indicate that VA has both anticonvulsive and suppressive effects on seizures and lipid peroxidation induced by ferric chloride in rats. Data from the present study also demonstrate that VA has free radical scavenging activities, which may be responsible for its anticonvulsive properties. This finding is consistent with the results from previous studies that generation of superoxide radical evoked by injection of iron salt into rat brain plays a critical role in ferric chloride-induced seizures. In addition, the results of the present study suggest that the anticonvulsive effect of GE may be attributable, at least in part, to its VA component.

Subsurface Injection of Dissolved Ferric Chloride to Form a Chemical Barrier: Laboratory Investigations

AbstractA chemical barrier is a permeable zone of reactive materials emplaced in the subsurface to remove ground‐water contaminants while allowing clean ground water to pass through. Because dissolved ferric chloride hydrolyzes to amorphous ferric oxyhydroxide when it contacts calcite (CaCO3), it may be viable to emplace a zone of amorphous ferric oxyhydroxide (an absorbent for U, Mo, and other inorganic contaminants) into calcite‐bearing geologic units by injecting ferric chloride through wells. For a chemical barrier to be successful, it must remain permeable and must be immobile.This investigation monitored chemical compositions, hydraulic conductivity, and iron mobility in laboratory columns and in a two‐dimensional tank to determine the viability of injecting ferric chloride to form an amorphous ferric oxyhydroxide chemical barrier. We introduced a ferric chloride solution (1,345 mg/l [0.024 m] Fe) to calcite‐bearing alluvial gravel to form a chemical barrier of amorphous ferric oxyhydroxide, followed by solutions contaminated with U and Mo. The simulated chemical barriers decreased U and Mo concentrations to less than 0.05 mg/1 (2.1×10‐7 m) and 0.01 (1.0×10‐7 m), respectively; however, the breakthrough front is spread out with concentrations increasing to more than regulatory guideline values sooner than predicted. The hydraulic conductivity of calcite‐bearing alluvial gravel decreased substantially during ferric chloride introduction because of the formation of carbon dioxide but increased to within factors of 1 to 5 of the original value as synthetic ground water flowed through the system. Amorphous ferric oxyhydroxide that formed in these experiments remained immobile at flow rates exceeding those typical of ground water. These laboratory results, in conjunction with site‐specific characterization data, can be used to design chemical barriers emplaced by injection of ferric chloride.

Antioxidant and free radical scavenging activities of Gastrodia elata Bl. and Uncaria rhynchophylla (Miq.) Jacks

Gastrodia elata Bl. (GE) and Uncaria rhynchophylla (Miq.) Jacks (UR) are two traditional Chinese medicinal herbal drugs, used for the treatment of convulsions and epilepsy. Their antioxidant effects in vivo and their free radical scavenging effects in vitro were investigated. Epileptogenic foci in the lateral brain of the rat were induced by the injection of ferric chloride into the lateral cortex. Both extracts significantly inhibited the increase in levels of lipid peroxide in the ipsilateral cortex, at all times observed. In addition, the two extracts also induced an early increase of activity of superoxide dismutase in the mitochondrial fraction of the ipsilateral cortex. In in vitro experiments, the two extracts exhibited significant dose-dependent scavenging effects on free radicals, using electron spin resonance spectroscopy. These results suggest that the proposed antiepileptic effects of GE and UR may be attributable to the antioxidant activity of the active components in these two medicinal herbs.

Biochemical pathogenesis of post-traumatic epilepsy

Head trauma is often followed by epilepsy and may be related to the breakdown of red blood cells and hemoglobin within the CNS. Injection of hemoglobin or iron salts into the rat cortex is known to induce a chronic epileptic focus. We observed the formation of superoxide anion (O2) and hydroxyl radical (.OH) after ferric chloride injection into the rat cerebral cortex and suggest that these radicals, especially .OH, may be responsible for the initiation of lipid peroxidation in neuronal membranes and for the accelerated production of guanidine compounds in the brain, which may in turn lead to epileptogenicity. Then, we found that treatment with epigallocatechin (EGC) or a phosphate diester of vitamins E and C (EPC), which are potent .OH scavengers, significantly inhibited the formation of malondialdehyde and epileptic discharges in the iron-induced epileptic focus.

Lipid Peroxidation and Glutathione Peroxidase, Glutathione Reductase, Superoxide Dismutase, Catalase, and Glucose‐6‐Phosphate Dehydrogenase Activities in FeCl3‐Induced Epileptogenic Foci in the Rat Brain

This study investigated the relationship between lipid peroxidation, subsequent activation of antioxidative enzymes, and development of iron-induced epilepsy in the rat. Epileptic foci were produced in rat cerebral cortex by intracortical injection of ferric chloride (FeCl3). The epileptic foci were identified by electrocorticography (ECoG). Epileptiform ECoG activity was shown to occur in the contralateral homotopic cerebral cortex as well. We measured levels of lipid peroxides and changes in the activities of the enzymes: superoxide dismutase (SOD), glutathione peroxidase (GP), glutathione reductase (GR), catalase (CA), and glucose-6-phosphate dehydrogenase (G6P) in the epileptogenic focus (both ipsilateral and contralateral) at days 3, 8, 15, and 23 after FeCl3 injection. Biochemical estimations were made in subcellular fractions, and changes in the ipsilateral site were compared with those in the contralateral site. The results of this study showed that large increases in lipid peroxidation were associated with development and buildup of the ECoG epileptiform discharges. Lipid peroxides increased in the ipsilateral focus by approximately 100% as compared with control. In the contralateral site, however, the increase in lipid peroxides was marginal only. The increase in lipid peroxidation was concomitant with development of the high level of epileptiform activity. The time course of changes in lipid peroxidation paralleled the time course of development and persistence of the epileptiform activity. Regarding changes in the enzyme activities accompanying development of iron epilepsy, the data showed that although SOD and G6P increased by approximately 60% and GR increased by approximately 40%, the increases in the enzyme GP and CA were much lower, less than 20%. Thus, comparatively less increase in CA and GP activities produces a deficiency of these two enzymes in the iron (ipsilateral) focus. Among the various biochemical disturbances that have been identified as involved in epileptogenesis, peroxidative injury resulting from lipid peroxidation in neural plasma membrane may be causally related to development of paroxysmal epileptiform activity in the iron focus. Since GP is an enzyme of major importance in detoxification of lipid peroxides in the brain, based on the results presented in this article, it appears reasonable to suggest that GP deficiency causes lipid peroxidation to increase tremendously during iron epileptogenesis.

Brain level changes of guanidino compound after ferric chloride injection into rat isocortex

Brain level changes of guanidino compound after ferric chloride injection into rat isocortex

Dopaminergic supersensitivity follows ferric chloride-induced limbic seizures

Injection of ferric chloride (FC) into the left amygdala of rats produced limbic seizures that lasted at least 3 weeks. In addition, FC-injected animals demonstrated motor impairment, decreased protesting vocalizations, and spontaneous stereotypies during a behavioral examination. An increase in apomorphine-induced stereotypies was also noted, and weekly administration of apomorphine for 3 weeks potentiated the increase in stereotypes produced by FC injection. These behavioral changes were associated with changes in postsynaptic dopamine D2 receptors. In animals injected only with FC, an increase in the [ 3H]-spiperone B max in the left nucleus accumbens and an increase in K d in the right nucleus accumbens were noted. In FC-injected animals challenged weekly with apomorphine for 3 weeks, increases in the [ 3H]-spiperone B max in both amygdalae, the left nucleus accumbens, and the right nucleus caudatus and increases in K d in the left amygdala and right nucleus accumbens were noted. Severance of the anterior commissure at the time of FC injection reversed most of these changes in behavior and dopamine receptor binding. Possible mechanisms for these changes are discussed, as well as the implications of these results for research on limbic dysfunction and psychopathology.

Cutaneous calciphylactic reactions in the mouse and the rat and the effects of diphosphonates on the reaction in the rat.

Calciphylaxis is a local tissue calcific reaction at the site of an injection of challenger substance given a critical time period after the oral administration of a sensitizer substance such as dihydrotachysterol (DHT), vitamin D or parathormone. Cutaneous calciphylaxis is readily induced in the rat but not in the mouse and this may be because, in the latter, the challenger substance is absorbed rapidly by macrophages. In the rat the administration of 500 micrograms/0.1 ml of DHT followed after 24 h by the subcutaneous (SC) injection of ferric chloride (FeCl3) (30 micrograms/0.1 ml) is followed rapidly by calcification of the SC site. There is an early transient acute inflammatory reaction with the incrustation of collagen fibres by the iron salt and an apparent exudation of calcium and phosphate ions from the bloodstream. These ions also become associated with collagen fibres. Two days after injection macrophages and multinucleated giant cells become the dominant cells. Calciphylaxis is a useful experimental model of ectopic calcification and is associated with an initial hypercalcaemia. The diphosphonates ethane-1-hydroxy-1, 1-diphosphonate (EHDP) and dichloromethylene diphosphonate (Cl2MDP) are effective inhibitors of the calciphylactic reaction when administered prior to the initiation of the experimental procedure.

Dopaminergic supersensitivity at distant sites following induced epileptic foci

Injection of ferric chloride (FeCl 3) into the left amygdaloid nucleus of the rat produced partial complex seizures. Subsequent repeated apomorphine challenges revealed steady development of behavioral dopaminergic supersensitivity, above that observed in saline-injected controls. The behavioral supersensitibity observed in FeCl 3-injected animals was accompanied by increases in 3H-spiroperidol binding in contralateral amygdala, striatum and ipsilateral nucleus accumbens. In contrast, saline-injected controls demonstrated bilateral decreases in 3H-spiroperidol binding in amygdala and striatum. The effects of FeCl 3 injection on the behavioral dopaminergic supersensitivity and 3H-spiroperidol binding were eliminated when the anterior commissure was severed.

Scale Formation in Sea-water Distilling Plants and its Prevention

The scales found in sea-water evaporators are formed of calcium sulphate, calcium carbonate, and magnesium hydroxide. Calcium sulphate scale can be avoided by using a sufficiently dilute brine concentration to maintain the sulphate in solution. The conditions are indicated under which the formation of this scale can be avoided. Calcium carbonate and magnesium hydroxide scales are shown to be due to the carbonate alkalinity in the sea water, which is limited and reasonably constant. These scales are due to the break-up of the bicarbonate ions in the sea-water as heating and boiling occur. Up to a well-defined range of operating temperatures, a scale that is predominantly of calcium carbonate is experienced. At higher temperatures, a scale predominantly of magnesium hydroxide is formed; but both types of scale may occur in the region of the change-over zone. It is shown that the break-up of the bicarbonate ions produces carbonate ions, which give rise to the calcium carbonate scale and that, with further heating and boiling, break-up of the carbonate ions occurs with the formation of hydroxyl ions, which combine with magnesium ions to form the magnesium hydroxide scale. It is shown that some of the alkalinity leaves the evaporator with the blow-down; as calcium carbonate in solution, or calcium carbonate and/or magnesium hydroxide in suspension. The amount of scale formed is found to be proportional to the amount of sea-water used, and no benefit is obtained by operating at low brine densities. It is shown that the rate of scale formation is greater for low temperatures than high temperatures, and increases with the temperature difference across the heating surface. Tests show that the use of organic dispersive compounds gives rise to a weaker scale structure, which allows some of the scale to be shed by cracking. The calcium carbonate and magnesium hydroxide scales can be completely prevented if the appropriate quantity of hydrogen ions is supplied by the injection of acids such as hydrochloric acid or sulphuric acid, or an acid salt such as sodium bisulphate. These scales can also be prevented by the injection of ferric chloride, which provides a supply of ferric ions. The ferric ions combine preferentially with the hydroxyl ions formed by the break-up of the bicarbonate and carbonate ions— thus allowing the formation of ferric hydroxide, which is very insoluble and is maintained in suspension in the brine without forming scale. Long-period tests on large commercial plants have confirmed the research tests.

STUDIES ON INFLAMMATION

Colloidal iron or ferric chloride injected into the inflamed peritoneal cavity is fixed in the cavity and fails to reach the retrosternal lymphatic nodes, whereas, in the absence of inflammation, iron accumulates in these nodes and becomes demonstrable by the Prussian blue reaction. Quantitative studies show that after intraperitoneal injection of ferric chloride the retrosternal lymphatic nodes of animals with normal peritoneal cavity contain approximately 56 per cent more iron than do the nodes of animals with inflamed peritoneal cavity. Ferric chloride injected into the circulating blood enters an inflamed area in the skin and the inflamed tissue gives the Prussian blue reaction. Quantitative determinations show that the amount of iron in inflamed areas is much greater than that found in inflamed areas of animals that have received no iron.