Sample records for dimercaprol
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Unilateral rubral tremors in Wilson′s disease treated with dimercaprol
Directory of Open Access Journals (Sweden)
Rahul T Chakor
2015-01-01
Full Text Available Tremors are reported as the most frequent neurological manifestation of Wilson′s disease (WD in some series. Postural tremors, rest tremors, action tremors and wing-beating (rubral tremors are the different types of tremors seen in WD. We report a patient of WD with unilateral rubral tremors refractory to 1-year therapy with Penicillamine and anti-tremor medications. The tremors decreased considerably after adding chelation therapy with dimercaprol. Combination of Penicillamine and dimercaprol is an effective decoppering measure in rubral tremors of WD.
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Tian, Ran; Shi, Riyi
2017-06-01
Acrolein is one of the most toxic byproducts of lipid peroxidation, and it has been shown to be associated with multiple pathological processes in trauma and diseases, including spinal cord injury, multiple sclerosis, and Alzheimer's disease. Therefore, suppressing acrolein using acrolein scavengers has been suggested as a novel strategy of neuroprotection. In an effort to identify effective acrolein scavengers, we have confirmed that dimercaprol, which possesses thiol functional groups, could bind and trap acrolein. We demonstrated the reaction between acrolein and dimercaprol in an abiotic condition by nuclear magnetic resonance spectroscopy. Specifically, dimercaprol is able to bind to both the carbon double bond and aldehyde group of acrolein. Its acrolein scavenging capability was further demonstrated by in vitro results that showed that dimercaprol could significantly protect PC-12 cells from acrolein-mediated cell death in a dose-dependent manner. Furthermore, dimercaprol, when applied systemically through intraperitoneal injection, could significantly reduce acrolein contents in spinal cord tissue following a spinal cord contusion injury in rats, a condition known to have elevated acrolein concentration. Taken together, dimercaprol may be an effective acrolein scavenger and a viable candidate for acrolein detoxification. © 2017 International Society for Neurochemistry.
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Archer, Stephen Lawrence
2008-01-01
A case of left bundle branch block and a dilated, nonhypertrophic cardiomyopathy associated with ingestion of colloidal gold and silver as an ‘energy tonic’ is described. The cardiac disease was reversed within two months by a course of dimercaprol (Akorn Inc, USA) (British antiLewisite) and vitamin E. This is the first case of gold and silver cardiomyopathy in humans, and highlights the risks of these colloidal metal ‘health supplements’. PMID:18464946
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Energy Technology Data Exchange (ETDEWEB)
Mouret, Stéphane, E-mail: stephane.mouret@irba.fr [Département de Toxicologie et Risques Chimiques, Institut de Recherche Biomédicale des Armées, Centre de Recherches du Service de Santé des Armées, 24 avenue Maquis du Grésivaudan, 38700 La Tronche (France); Wartelle, Julien; Emorine, Sandy; Bertoni, Marine; Nguon, Nina; Cléry-Barraud, Cécile [Département de Toxicologie et Risques Chimiques, Institut de Recherche Biomédicale des Armées, Centre de Recherches du Service de Santé des Armées, 24 avenue Maquis du Grésivaudan, 38700 La Tronche (France); Dorandeu, Frédéric [Département de Toxicologie et Risques Chimiques, Institut de Recherche Biomédicale des Armées, Centre de Recherches du Service de Santé des Armées, 24 avenue Maquis du Grésivaudan, 38700 La Tronche (France); Ecole du Val-de-Grâce, 1 place Alphonse Laveran, Paris (France); Boudry, Isabelle [Département de Toxicologie et Risques Chimiques, Institut de Recherche Biomédicale des Armées, Centre de Recherches du Service de Santé des Armées, 24 avenue Maquis du Grésivaudan, 38700 La Tronche (France)
2013-10-15
Lewisite is a potent chemical warfare arsenical vesicant that can cause severe skin lesions. Today, lewisite exposure remains possible during demilitarization of old ammunitions and as a result of deliberate use. Although its cutaneous toxicity is not fully elucidated, a specific antidote exists, the British anti-lewisite (BAL, dimercaprol) but it is not without untoward effects. Analogs of BAL, less toxic, have been developed such as meso-2,3-dimercaptosuccinic acid (DMSA) and have been employed for the treatment of heavy metal poisoning. However, efficacy of DMSA against lewisite-induced skin lesions remains to be determined in comparison with BAL. We have thus evaluated in this study the therapeutic efficacy of BAL and DMSA in two administration modes against skin lesions induced by lewisite vapor on SKH-1 hairless mice. Our data demonstrate a strong protective efficacy of topical application of dimercapto-chelating agents in contrast to a subcutaneous administration 1 h after lewisite exposure, with attenuation of wound size, necrosis and impairment of skin barrier function. The histological evaluation also confirms the efficacy of topical application by showing that treatments were effective in reversing lewisite-induced neutrophil infiltration. This protective effect was associated with an epidermal hyperplasia. However, for all the parameters studied, BAL was more effective than DMSA in reducing lewisite-induced skin injury. Together, these findings support the use of a topical form of dimercaprol-chelating agent against lewisite-induced skin lesion within the first hour after exposure to increase the therapeutic management and that BAL, despite its side-effects, should not be abandoned. - Highlights: • Topically applied dimercapto-chelating agents reduce lewisite-induced skin damage. • One topical application of BAL or DMSA is sufficient to reverse lewisite effects. • Topical BAL is more effective than DMSA to counteract lewisite-induced skin damage.
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Interventions for paracetamol (acetaminophen) overdose
DEFF Research Database (Denmark)
Chiew, Angela L; Gluud, Christian; Brok, Jesper
2018-01-01
BACKGROUND: Paracetamol (acetaminophen) is the most widely used non-prescription analgesic in the world. Paracetamol is commonly taken in overdose either deliberately or unintentionally. In high-income countries, paracetamol toxicity is a common cause of acute liver injury. There are various...... of paracetamol. Acetylcysteine should be given to people at risk of toxicity including people presenting with liver failure. Further randomised clinical trials with low risk of bias and adequate number of participants are required to determine which regimen results in the fewest adverse effects with the best...... was abandoned due to low numbers recruited), assessing several different interventions in 700 participants. The variety of interventions studied included decontamination, extracorporeal measures, and antidotes to detoxify paracetamol's toxic metabolite; which included methionine, cysteamine, dimercaprol...
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Animals afflicted with lead poisoning from motor exhaust
Energy Technology Data Exchange (ETDEWEB)
Scheel-Thomsen, A
1956-01-01
Three cases of dogs treated for ulcerous conditions of the oral cavity and a trembling of the limbs, which were eventually discovered to be lead poisoning derived from constant exposure to gasoline and automotive exhaust, are reported. The first case, typical of all three, was first treated in April 1951. The lesions healed after a stay in the hospital but recurred after he returned home. The dog was also asymptomatic when at the owner's summer home for any length of time. It was discovered that at his winter home the dog spent much of his time around a large automobile garage. After treatment with Antoxol (dimercaprol) and benzyl benzoate, he recovered and had no more symptoms of lead poisoning until his death from cancer several years later. Each of the three involved an animal whose daily activities exposed him to the continual presence of gasolines and exhaust fumes containing tetraethyl lead.
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Chelation in Metal Intoxication
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Swaran J.S. Flora
2010-06-01
Full Text Available Chelation therapy is the preferred medical treatment for reducing the toxic effects of metals. Chelating agents are capable of binding to toxic metal ions to form complex structures which are easily excreted from the body removing them from intracellular or extracellular spaces. 2,3-Dimercaprol has long been the mainstay of chelation therapy for lead or arsenic poisoning, however its serious side effects have led researchers to develop less toxic analogues. Hydrophilic chelators like meso-2,3-dimercaptosuccinic acid effectively promote renal metal excretion, but their ability to access intracellular metals is weak. Newer strategies to address these drawbacks like combination therapy (use of structurally different chelating agents or co-administration of antioxidants have been reported recently. In this review we provide an update of the existing chelating agents and the various strategies available for the treatment of heavy metals and metalloid intoxications.
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Quadriplegia due to lead-contaminated opium--case report.
Beigmohammadi, Mohammad Taghi; Aghdashi, Moosa; Najafi, Atabak; Mojtahedzadeh, Mojtaba; Karvandian, Kassra
2008-10-01
Utilization of lead-contaminated opium may lead to severe motor neuron impairment and quadriplegia. Forty years oriented old male, opium addict, was admitted to the ICU, with headache, nausea and abdominal pain, and weakness in his lower and upper extremities without definitive diagnosis. The past medical and occupational history was negative. Laboratory investigation showed; anemia (Hb 7.7 g/dl), slightly elevated liver function tests, elevated total bilirubin, and ESR. Abdominal sonography and brain CT scan were normal. EMG and NCV results and neurologic examination were suggestive for Guillain-Barre. He underwent five sessions of plasmapheresis. Blood lead level was > 200 microg/dl. He received dimercaprol (BAL) and calcium disodium edetate (CaEDTA) for two five days session. Upon discharge from ICU all laboratory tests were normal and blood lead level was reduced, but he was quadriplegic. The delayed treatment of lead poisoning may lead to irreversible motor neuron defect.
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Cao, B J; Chen, Z K; Chi, Z Q
1990-03-01
Sodium dimercaptopropanesulphonate (DMPS) and sodium dimercaptosuccinate (DMS) were discovered to be effective antidotes for acute poisoning of insecticides SCD [sodium ammonium dimethyl-2-(propane-1,3-dithiosulfate) monohydrate], nereistoxin (4-N,N-dimethylamino-1,2-dithiolane) and cartap (dihydronereistoxin dicarbamate). In mice, DMPS (250 mg/kg) or DMS (1000 mg/kg) ip 20 min before SCD increased LD50 of ig SCD from 97 to 374 or 251 mg/kg, respectively. The prophylactic effect of DMPS was better than that of DMS. Administration of DMPS prior to cartap increased LD50 of ig cartap from 130 to 375 mg/kg. The therapeutic effect of DMPS was also demonstrated in SCD-poisoned conscious rabbits. DMPS 62.5 mg/kg or DMS 500 mg/kg iv completely antagonized the neuromuscular blockade and respiratory depression caused by SCD, nereistoxin and cartap in anesthetized rabbits. The antagonism of SCD-induced neuromuscular blockade by cysteine (400 mg/kg, iv) was less effective and of shorter duration than that by DMPS and DMS. Dimercaprol 50 mg/kg im showed little effect on SCD-induced paralysis. The antagonistic actions of sulfhydryl compounds on neuromuscular blockade induced by these insecticides probably belong to chemical antagonism.
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The putative cocaine receptor in striatum is a glycoprotein with thiol function
International Nuclear Information System (INIS)
Cao, C.J.; Young, M.M.; Wang, J.B.; Mahran, L.; Eldefrawi, M.E.
1990-01-01
Dopamine transporters of bovine and rat striata are identified by their specific [ 3 H] cocaine binding and cocaine-sensitive [ 3 H] dopamine ([ 3 H]DA) uptake. Both binding and uptake functions of bovine striatal transporters were potentiated by lectins. Concanavalin A (Con A) increased the velocity but did not change the affinity of the transporter for DA. On the other hand, ConA increased its affinity for cocaine without changing the number of binding sites. The data suggest that the DA transporter is a glycoprotein. Inorganic and organic mercury reagents inhibited both [ 3 H] cocaine binding, though they were all more potent inhibitors of the former. N-ethylmaleimide inhibited [ 3 H]DA uptake totally but [ 3 H]cocaine binding only partially. Also, N-pyrenemaleimide had different effects on uptake and binding, inhibiting uptake and potentiating binding. [ 3 H]DA uptake was not affected by mercaptoethanol up to 100 mM whereas [ 3 H]cocaine binding was inhibited by concentration above 10 mM. On the other hand, both uptake and binding were fairly sensitive to dimercaprol ( 10 mM). Loss of activity after treatment with the dithio reagents may be a result of reduction of a disulfide bond, which may affect the transporter conformation
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Decontamination of radioactive materials (part II)
Energy Technology Data Exchange (ETDEWEB)
Akashi, Makoto; Shimomura, Satoshi; Hachiya, Misao [National Inst. of Radiological Sciences, Chiba (Japan)
1998-06-01
Drifting agents accelerate the exchange process and thus promote to eliminate radioactive materials from human body. The earlier is the administration of the agent, the more effective is the elimination. Against the uptake of radioiodine by thyroid, anti-thyroid drug like NaI, Lugol`s iodine solution, propylthiouracil and methimazole are recommended. Ammonium chloride can be a solubilizer of radioactive strontium. Diuretics may be useful for excretion of radioisotopes of sodium, chlorine, potassium and hydrogen through diuresis. Efficacy of expectorants and inhalants is not established. Parathyroid extract induces decalcification and thus is useful for elimination of 32P. Steroids are used for compensating adrenal function and for treatment of inflammation and related symptoms. Chelating agents are useful for removing cations and effective when given early after contamination. EDTA and, particularly, DTPA are useful for elimination of heavy metals. For BAL (dimercaprol), its toxicity should be taken into consideration. Penicillamine is effective for removing copper and deferoxamine, for iron. Drugs for following radioisotopes are summarized: Am, As, Ba, Br, Ca, Cf, C, Ce, Cs, Cr, Co, Cm, Eu, fission products, F, Ga, Au, H, In, I, Fe, Kr, La, PB, Mn, Hg, Np, P, Pu, Po, K, Pm, Ra, Rb, Ru, Sc, Ag, Na, Sr, S, Tc, Th, U, Y, Zn and Zr. Lung and bronchia washing are effective for treatment of patients who inhaled insoluble radioactive particles although their risk-benefit should be carefully assessed. The present review is essentially based of NCRP Report No.65. (K.H.) 128 refs.
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International Nuclear Information System (INIS)
Coveney, J.R.; Robbins, M.S.
1986-01-01
There is clinical interest in /sup 195m/Hg//sup 195m/Au generators for radionuclide angiocardiography. Generators are /sup 195m/Hg-impregnated columns through which S 2 O 3 2- /NO 3 - eluant is passed to recover /sup 195m/Au daughter (t/sub 1/2p/ approx. 30s) permitting repeated patient study at short intervals, but co-elution of some /sup 195m/Hg (t/sub 1/2p approx. 40h) limits per-study dose: eluate was injected i.v. to male and female New Zealand White rabbits (1.4-2.4 kg, 12 ml eluate ea.); approx. 40% of injected dose (ID) of /sup 195m/Hg was in kids by 3d and approx. 20% ID remained after 14d; only 37% ID was excreted (2/3 in feces) at 7d. To evaluate DMPS action upon kid /sup 195m/Hg burden, male Sprague-Dawley rats (187-240 g) were injected i.v. with 2ml eluate containing 0.02 mg DMPS/ml or eluate alone. DMPS slightly reduced % ID /sup 195m/Hg in kids 22h later: 12.2 +/- 0.3 to 8.5 +/- 0.3 (mean +/- s.e.m., n = 4). Additional rats were given 5 mg BAL/kg, i.p., or 2ml propylene glycol vehicle/kg 3-4' before 2ml eluate, i.v.; % ID of Hg was again only slightly reduced (14.4 +/- 0.2 to 10.7 +/- 0.1). Neither BAL nor DMPS, useful in repeat-dose regimens in heavy metal poisoning, are suitable in single doses for reducing absorbed radiation dose in /sup 195m/Au angiocardiography
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Quadriplegia due to lead-contaminated opium: a case report
Directory of Open Access Journals (Sweden)
Baigmohammadi MT
2008-10-01
Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Lead poisoning could be associated with gastrointestinal renal, hematologic complications and neurologic deficit."n"n Case report: The patient was an opium addict, forty one years old male, to hospital admitted with gastrointestinal signs, constipation, abdominal pain, severe weakness of upper and lower limbs without any sensory impairment and with anemia, leukocytosis, and slightly increased liver function tests. Serum level of lead was more than 200µg/dl. After treatment with dimercaprol (BAL, CaNa2EDTA for two five days sessions that followed with oral succimer for three days, signs and symptoms relieved, all laboratory tests became normal and blood level of lead reduced but the patient was discharged with quadriplegia. There was no fecal or urinary incontinence."n"n Conclusions: Because of irreversibility and severity of lead related neuronal injury, we should suspect to lead poisoning in each patient with neuronal involvement and concurrent GI and hematologic signs."n"n Keywords: Lead poisoning, motor palsy, opium, neuropathy, quadriplegia.
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Inhibition of lipase and inflammatory mediators by Chlorella lipid extracts for antiacne treatment.
Sibi, G
2015-01-01
Acne vulgaris is a chronic inflammatory disease, and its treatment is challenging due to the multifactorial etiology and emergence of antibiotic-resistant Propionibacterium acnes strains. This study was focused to reduce antibiotics usage and find an alternate therapeutic source for treating acne. Lipid extracts of six Chlorella species were tested for inhibition of lipase, reactive oxygen species (ROS) production, cytokine production using P. acnes (Microbial Type Culture Collection 1951). Lipase inhibitory assay was determined by dimercaprol Tributyrate - 5, 5'- dithiobis 2-nitrobenzoic acid method and ROS production assay was performed using nitro-blue tetrazolium test. The anti-inflammatory activity of algal lipid extracts was determined by in vitro screening method based on inhibition of pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α) produced by human peripheral blood mononuclear cells. Minimum inhibitory concentration (MIC) values of lipid extracts were determined by microdilution method, and the fatty acid methyl esters (FAME) were analyzed by gas chromatography-mass spectroscopy. Chlorella ellipsoidea has the highest lipase inhibitory activity with 61.73% inhibition, followed by Chlorella vulgaris (60.31%) and Chlorella protothecoides (58.9%). Lipid extracts from C. protothecoides and C. ellipsoidea has significantly reduced the ROS production by 61.27% and 58.34% respectively. Inhibition of pro-inflammatory cytokines TNF-α showed the inhibition ranging from 58.39% to 78.67%. C. vulgaris has exhibited the MICvalue of 10 μg/ml followed by C. ellipsoidea, C. protothecoides and Chlorella pyrenoidosa (20 μg/ml). FAME analysis detected 19 fatty acids of which 5 were saturated fatty acids, and 14 were unsaturated fatty acids ranging from C14 to C24. The results suggest that lipid extracts of Chlorella species has significant inhibitory activity on P. acnes by inhibiting lipase activity. Further, anti-inflammatory reaction caused by the
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Inhibition of lipase and inflammatory mediators by Chlorella lipid extracts for antiacne treatment
Directory of Open Access Journals (Sweden)
G Sibi
2015-01-01
Full Text Available Acne vulgaris is a chronic inflammatory disease, and its treatment is challenging due to the multifactorial etiology and emergence of antibiotic-resistant Propionibacterium acnes strains. This study was focused to reduce antibiotics usage and find an alternate therapeutic source for treating acne. Lipid extracts of six Chlorella species were tested for inhibition of lipase, reactive oxygen species (ROS production, cytokine production using P. acnes (Microbial Type Culture Collection 1951. Lipase inhibitory assay was determined by dimercaprol Tributyrate - 5, 5′- dithiobis 2-nitrobenzoic acid method and ROS production assay was performed using nitro-blue tetrazolium test. The anti-inflammatory activity of algal lipid extracts was determined by in vitro screening method based on inhibition of pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α produced by human peripheral blood mononuclear cells. Minimum inhibitory concentration (MIC values of lipid extracts were determined by microdilution method, and the fatty acid methyl esters (FAME were analyzed by gas chromatography-mass spectroscopy. Chlorella ellipsoidea has the highest lipase inhibitory activity with 61.73% inhibition, followed by Chlorella vulgaris (60.31% and Chlorella protothecoides (58.9%. Lipid extracts from C. protothecoides and C. ellipsoidea has significantly reduced the ROS production by 61.27% and 58.34% respectively. Inhibition of pro-inflammatory cytokines TNF-α showed the inhibition ranging from 58.39% to 78.67%. C. vulgaris has exhibited the MICvalue of 10 μg/ml followed by C. ellipsoidea, C. protothecoides and Chlorella pyrenoidosa (20 μg/ml. FAME analysis detected 19 fatty acids of which 5 were saturated fatty acids, and 14 were unsaturated fatty acids ranging from C14 to C24. The results suggest that lipid extracts of Chlorella species has significant inhibitory activity on P. acnes by inhibiting lipase activity. Further, anti-inflammatory reaction caused
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Energy Technology Data Exchange (ETDEWEB)
Tran, Lytuong [College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006 (China); QuangBinh University, QuangBinh (Viet Nam); Wu, Pingxiao, E-mail: pppxwu@scut.edu.cn [College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006 (China); The Key Laboratory of Environmental Protection and Eco-Remediation of Guangdong Regular Higher Education Institutions (China); Zhu, Yajie; Liu, Shuai; Zhu, Nengwu [College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006 (China)
2015-11-30
Graphical abstract: - Highlights: • Novel adsorbents were prepared by functionalization with BAL to remove Hg(II). • Thiol and hydroxyl groups contributed to the enhancement of Hg(II) removal. • BAL-Vm showed the most adsorption capacity of Hg(II). • The adsorption mechanism was discussed based on the adsorption behaviors. - Abstract: A novel approach to prepare adsorbents for Hg(II) uptake from aqueous media based on the grafting of dimercaprol (BAL), containing thiol and hydroxyl groups, onto the natural montmorillonite and vermiculite was investigated concerning the evaluation of the adsorption capacity. The kinetic study showed that the adsorption process abided by pseudo-second-order model. The adsorption behavior of Hg(II) onto the obtained samples fitted well with Langmuir isotherm model, exhibiting an enhanced maximum adsorption capacity of 8.57 and 3.21 mg g{sup −1} for BAL-Vm and BAL-Mt, respectively. The feasibility of Hg(II) uptake onto the the samples was studied thermodynamically and the calculated coefficients such as ΔH, ΔS and ΔG indicated a physical and spontaneous process. The pH values and coexisting cations had a great influence on Hg(II) removal, confirming the optimal pH value of 4.0–5.0 and the negative correlation between the ionic strength and the adsorption capacity of Hg(II). In general, BAL-Vm possessed a higher efficiency of Hg(II) uptake than BAL-Mt, contrary to that of the pristine clays. The pristine and functionalized materials were investigated by XRD, FTIR, BET, SEM and zeta potential analysis to gain in-depth insight into the structure and surface morphology. The results showed that BAL was successful grafted on montmorillonite and vermiculite surface, providing plentiful adsorption sites as chelating ligands. The mechanisms of Hg(II) adsorption on these samples could be further explained as ion exchange and electrostatic attraction for Vm and Mt, and formation of complexes for BAL-Vm and BAL-Mt.
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International Nuclear Information System (INIS)
Tran, Lytuong; Wu, Pingxiao; Zhu, Yajie; Liu, Shuai; Zhu, Nengwu
2015-01-01
Graphical abstract: - Highlights: • Novel adsorbents were prepared by functionalization with BAL to remove Hg(II). • Thiol and hydroxyl groups contributed to the enhancement of Hg(II) removal. • BAL-Vm showed the most adsorption capacity of Hg(II). • The adsorption mechanism was discussed based on the adsorption behaviors. - Abstract: A novel approach to prepare adsorbents for Hg(II) uptake from aqueous media based on the grafting of dimercaprol (BAL), containing thiol and hydroxyl groups, onto the natural montmorillonite and vermiculite was investigated concerning the evaluation of the adsorption capacity. The kinetic study showed that the adsorption process abided by pseudo-second-order model. The adsorption behavior of Hg(II) onto the obtained samples fitted well with Langmuir isotherm model, exhibiting an enhanced maximum adsorption capacity of 8.57 and 3.21 mg g −1 for BAL-Vm and BAL-Mt, respectively. The feasibility of Hg(II) uptake onto the the samples was studied thermodynamically and the calculated coefficients such as ΔH, ΔS and ΔG indicated a physical and spontaneous process. The pH values and coexisting cations had a great influence on Hg(II) removal, confirming the optimal pH value of 4.0–5.0 and the negative correlation between the ionic strength and the adsorption capacity of Hg(II). In general, BAL-Vm possessed a higher efficiency of Hg(II) uptake than BAL-Mt, contrary to that of the pristine clays. The pristine and functionalized materials were investigated by XRD, FTIR, BET, SEM and zeta potential analysis to gain in-depth insight into the structure and surface morphology. The results showed that BAL was successful grafted on montmorillonite and vermiculite surface, providing plentiful adsorption sites as chelating ligands. The mechanisms of Hg(II) adsorption on these samples could be further explained as ion exchange and electrostatic attraction for Vm and Mt, and formation of complexes for BAL-Vm and BAL-Mt.
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Interventions for paracetamol (acetaminophen) overdose.
Chiew, Angela L; Gluud, Christian; Brok, Jesper; Buckley, Nick A
2018-02-23
benefits and underestimation of harms). We used Trial Sequential Analysis to control risks of random errors (i.e. play of chance) and GRADE to assess the quality of the evidence and constructed 'Summary of findings' tables using GRADE software. We identified 11 randomised clinical trials (of which one acetylcysteine trial was abandoned due to low numbers recruited), assessing several different interventions in 700 participants. The variety of interventions studied included decontamination, extracorporeal measures, and antidotes to detoxify paracetamol's toxic metabolite; which included methionine, cysteamine, dimercaprol, or acetylcysteine. There were no randomised clinical trials of agents that inhibit cytochrome P-450 to decrease the activation of the toxic metabolite N-acetyl-p-benzoquinone imine.Of the 11 trials, only two had two common outcomes, and hence, we could only meta-analyse two comparisons. Each of the remaining comparisons included outcome data from one trial only and hence their results are presented as described in the trials. All trial analyses lack power to access efficacy. Furthermore, all the trials were at high risk of bias. Accordingly, the quality of evidence was low or very low for all comparisons. Interventions that prevent absorption, such as gastric lavage, ipecacuanha, or activated charcoal were compared with placebo or no intervention and with each other in one four-armed randomised clinical trial involving 60 participants with an uncertain randomisation procedure and hence very low quality. The trial presented results on lowering plasma paracetamol levels. Activated charcoal seemed to reduce the absorption of paracetamol, but the clinical benefits were unclear. Activated charcoal seemed to have the best risk:benefit ratio among gastric lavage, ipecacuanha, or supportive treatment if given within four hours of ingestion. There seemed to be no difference between gastric lavage and ipecacuanha, but gastric lavage and ipecacuanha seemed more