High Anion Research Articles

Energy recovery and waste treatment using the co-pyrolysis of biomass waste and polymer.

The pyrolysis of spent coffee grounds (SCG) and polymers was examined as a waste treatment option for energy recovery and carbon sequestration. Rice straw-derived biochar was used as control biochar to evaluate the sorption capacity and energy production capability of SCG-derived biochar. SCG are characterised by high levels of volatile matter, rendering them suitable as an energy source. SCG were converted to biochar, bio-oil, and syngas via pyrolysis, with yields of 22%, 33%, and 45%, respectively. The high heating value (HHV) of the biochar and bio-oil was 20.6 and 22.9 MJ kg-1, respectively, indicating that they could be used as supplementary fuels. Co-pyrolysis with polymers (20 v v%-1) increased the HHV of biochar. Accordingly, the maximum production of CH4 and H2 increased from 0.3 and 0.04 mmol g-1 to 3.4-6.3 and 0.8-1.3 mmol g-1, respectively. Polystyrene most strongly enhanced the yields of CH4 and H2, followed by polypropylene and polyethylene; this order was likely to be in accordance with the number of carbon and hydrogen atoms present in the monomers. Similar to rice straw-derived biochar, the biochar produced from SCG demonstrated a high sorption capacity for 2,4-dinitrotoluene and chromate due to its high carbon content and anion exchange capacity, respectively. Laboratory pot tests revealed that the coffee grounds-derived biochar was able to increase the growth of young radish. Our results suggest that the pyrolysis of SCG and polymer may be a promising option for waste treatment, energy production, and carbon sequestration.

Chemically stable and high acid recovery anion exchange membrane

Herein we are reporting a base-catalysed carbanion formation of N-methyl-4-piperidone (NMPi) and thermoset anion exchange membrane thereof. N-methyl-4-piperidone (NMPi) was reacted with formaldehyde in presence of sodium hydroxide to obtain NMPi-formaldehyde based prepolymer. An anion exchange membrane (AEM) was obtained by grafting prepolymer on to polyvinyl alcohol (PVA) by thermal annealing followed by quaternization. By varying the NMPi/PVA ratio, four AEMs namely M1-M4 was synthesized. Detailed physicochemical, microscopic, thermal and dimensional stability studies were performed to assess their applicability. AEMs were explored for acid recovery from hydrochloric acid (HCl), sulphuric acid (H2SO4), acetic acid (CH3COOH), simulated feed (2 M HCl containing 6% FeSO4) and effluent from a local bentonite mine (acid concentration ∼8 M) by diffusion dialysis. Proton dialysis coefficient (UH+) of 22 × 10−3 m h−1, Fe2+ dialysis coefficient (UFe2+) of 1.94 × 10−5 m h−1 and separation factor (S) of 112 units for best performing membrane was obtained for simulated feed. Acid recovery of 80% was achieved in 50 h from effluent obtained from local bentonite mine by changing the permeate side thrice at diffusion equilibrium; encouraging its best applicability and stability in highly acidic environment.

Communication—Electropolymerization of Anion-Conducting Polymer Films

We successfully electropolymerize homopolymer and copolymer from vinylbenzyltrimethylammonium chloride (VBTMA) and divinylbenzene (DVB) by cyclic voltammetry to form ultra-thin anion-conducting polymer films with significant anion conductance. The morphologies of electropolymerized polymers with different monomer compositions are analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). In-situ electrochemical impedance spectroscopy (in situ EIS) is performed to track the electropolymerization (EP) process and film properties. High anion conductance of up to 2 mS is found in the electropolymerized thin films, suggesting that this technique can be suitable for making anion-conducting electrodes for advanced electrochemical devices.

Biomass-Derived Anion-Anchoring Nano-CaCO3Coating for Regulating Ion Transport on Li Metal Surface

The free transport of anions in a Li metal battery can cause multiple issues, including a high anion transference number, space charge, and concentration polarization, eventually leading to uncontrolled dendrite formation and decreased performance. Herein, we report an anion-anchoring nano-CaCO3 (NC) coating derived from eggshell biowaste for stabilizing Li metal anodes. As the adsorption of local TFSI- anions onto the NC adsorbent can undermine the anion concentration gradient and promote rapid Li-ion diffusion, it can effectively inhibit the proliferation of Li dendrites assisted by the NC coating. Consequently, Li/Cu cells with NC@Cu electrode can achieve a high Coulombic efficiency of ∼98.4% for more than 420 cycles and can even reach ∼99.1% at an ultrahigh areal capacity of 20 mAh cm-2. In particular, full cells with NC/Li@Cu electrodes show a stable lifespan of over 240 cycles with an average efficiency of ∼99.8% at a low N/P ratio of ∼3.3.

Cardiovascular manifestations of acute aluminium phosphide poisoning and their impact on survival

Background: Aluminium phosphide (AlP) is a common suicidal poison with a high mortality rate due to its cardiovascular impact and lack of antidote. The aim of the study was to describe the electrocardiographic changes and other cardio-vascular manifestations in acute AlP poisoning and evaluate its impact on survival outcomes.Methods: A prospective cross-sectional study was conducted in a tertiary care hospital including patients who presented with acute AlP ingestion in any form. Patients’ vitals and ECG at the time of admission were taken and outcomes of survival were identified. A descriptive study of echocardiography was also done. The clinical parameters were correlated with the survival outcomes.Results: Fifty patients were included with 30 males and 20 females. The consumption of AlP in tablet form caused more hemodynamic compromise (hypotension and high anion gap metabolic acidosis) as compared to the powder form. ECG changes were seen in 42% of the cases, the most common finding was prolonged QTc interval (26%). The mortality was 30%. Hypotension, bradycardia, and QRS widening were found to be significant predictors of mortality (p<0.05). Echocardiography was performed for 10 patients, of which, one had right ventricular dysfunction and two had left ventricular dysfunction.Conclusions: AlP tablets are more lethal and hemodynamically compromising than AlP powder. Hypotension, bradycardia, and QRS widening are significant predictors of mortality. Direct cardiotoxicity leads to ECG changes, of which, QTc prolongation is the most common.

Oxygen Electrochemical Production from Air by High Performance Anion Exchange Membrane Electrode Assemble Devices

CoNi and FeCoNi hydroxide with narrow voltage distance between oxygen reduction reaction and oxygen evolution reaction was synthetized by electro-deposition in low solvent concentration. 5cm2 Membrane electrode assemble (MEA) electrolyzers composed with anion exchange membrane, homogenerated catalyst on both cathode and anode gas diffusion layer (GDL) was fabricated for oxygen electrochemical production from air. The current and yield of binary CoNi device reached up to 466.7mA and 4.4mmol/h (94.7% conversion rate) at 1.2V. The ternary FeCoNi device showed only 0.5% degradation from 394.0mA during 12h. The applicability of oxygen production from air by high performance electrochemical devices was demonstrated.

Counterion effect on α-Keggin polyoxometalates in water: The peculiar role of H+ on their salting-in effect and co-assembly with organics

Hofmeister effects of ions in aqueous solution strongly affect chemical and biological systems. High and low charge density anions, such as SO42- and SCN- respectively, decrease (salting-out) or increase (salting-in) the solubility of organic solutes in water. Due to their very low charge-density, nanometric anions, e.g. polyoxometalates (POMs), increase the solubility of organic solutes tremendously (highly salting-in) as they bind to neutral hydrated solutes strongly – a property that is attributed to the (super-)chaotropic effect. Here, we show that salting-out anions can be turned into salting-in anions in the presence of a superchaotropic POM, α-PW12O403-. The effect of salts composed of salting-out anions, e.g. SO42-, was investigated on the cloud point (CP) of an ethoxylated surfactant (C8E4) and a propoxylated co-solvent (C3P2) in the presence of SiW12O404- and PW12O403- with different counter-cations (H+, Li+, Na+, K+). SiW12O404- and PW12O403- lead to a monotonic strong CP-increase regardless of the counterion, except for PW12O403- combined with H+. Indeed, H3PW12O40 shows a CP decrease at high POM concentrations. This peculiar behavior is attributed to the formation of large H3PW12O40-C3P2 (and H3PW12O40-C8E4) co-assemblies, as shown by SAXS. The formation of these co-assemblies results from the “bridging” effect of H+ and the lower charge density of PW12O403- compared to SiW12O404-. The addition of (basic) salting-out anions leads to (i) the consumption of H+, then to (ii) the disruption of the large H3PW12O40-C3P2 (and H3PW12O40-C8E4) co-assemblies and subsequently to (iii) a CP-increase. In the peculiar case, this shows how commonly used salting-out anions can become apparently salting-in.

Isolation, Structural Analysis and Anti-Inflammatory Activity of a Polysaccharide from Ilex cornuta Fruits.

In the present study, a polysaccharide from Ilex cornuta fruits (LCFP-3) was obtained by hot water extraction, Diethyaminoethyl cellulose-52 (DEAE-52) chromatography column and Sephadex G-100 gel column purification. Its structural characteristics were further explored using high performance anion exchange chromatography (HPAEC), gas chromatography and mass spectrometry (GC/MS), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Monosaccharide composition analysis revealed LCFP-3 contained mainly Galactose (31.92 %), Arabinose (25.87 %) and Galacturonic acid (23.35 %) while small percentage of Rhamnose, Glucose, Mannose and Xylose. Chemical composition analysis showed that the total sugar content of LCFP-3 was 90.31 % and the protein content was 0.246 %. Gel permeation chromatography (GPC) analysis showed that its average molecular weight was 41.199 kDa. Structural analysis showed that LCFP-3 may be composed of residues, T-α-Arap, T-α-Rhap, 1,3-α-Arap, 1,4-α-Arap, T-β-Galp, 1,4-α-GalpA(OMe), 1,4-β-Glcp, 1,3-β-Galp, 1,3,6-β-Manp, 1,6-β-Galp, 1,3,4-β-GalpA, 1,4,6-β-Manp, 1,3,6-β-Glcp, 1,2,3,4-α-Xylp. The anti-inflammatory activity of LCFP-3 was evaluated using lipopolysaccharide (LPS)-induced RAW246.7 macrophages. The results showed that 1-200 μg/mL LCFP-3 could dose-dependently protect against LPS-induced toxicity and 1 μg/mL LCFP-3 could significantly inhibit LPS-induced NO production. Therefore, LCFP-3 exerted an anti-inflammatory activity and has great potential as a functional ingredient.

IDF21-0180 Alpelisib-induced coexisting of Diabetic Ketoacidosis and Hyperglycemic Hyperosmolar State in Metastatic Breast Cancer

Background: Alpelisib-induced Diabetic ketoacidosis (DKA) has been previously reported in the literature. In this case report, we describe the first case of Alpelisib-induced coexisting of DKA and hyperglycemic hyperosmolar state (HHS). Method: A 59-year-old woman, known to have advanced breast cancer with metastasis to bone, lungs, pleural, presented with a 2-day history of nausea, vomiting, and diffuse abdominal pain. Her breast cancer is ER (+), PR (+), and HER2 (+) with mutation of PIK3CA. She has been treated with hormonal and chemotherapy (Paclitaxel, Epirubicin and cyclophosphamide), but in vain. Further treatment with Alpelisib and fulvestrant was given for the treatment of breast cancer with PIK3CA mutation. Hyperglycemia was developed 7 days after medication. HbA1c level was 6.4%. Sitagliptin was prescribed to treat hyperglycemia. However, persistent hyperglycemia coexisting of DKA and HHS was developed 18 days later. Results: Laboratory data showed high anion gap metabolic acidosis, hyperosmolarity, hyperglycemia, and ketonemia, leading to the diagnosis of Alpelisib-associated HHS coexisting with DKA. Alpelisib was discontinued, and she was treated with intravenous insulin and hydration. After hyperglycemia was resolved, her blood glucose was managed using a regimen combining dapagliflozin and metformin. Discussion: This case highlights the importance of aggressive serum glucose monitoring in patients who taking Alpelisib to prevent hyperglycemic emergencies and notifies Sitagliptin treatment failure. Insulin is required at least during an acute hyperglycemic stage and oral SGLT2 inhibitor combine with metformin might be an effective treatment for Alpelisib-induced hyperglycemia. Future prospective studies are needed.

COMPARISON OF TWO DIFFERENT MODALITIES OF BICARBONATE FOR DETERMINATION OF ANION GAP IN CRITICALLY ILL PATIENTS

OBJECTIVE: To compare anion gap estimated through measured and calculated bicarbonate modalities to be used interchangeably in critically ill metabolic acidosis patients. METHODS: This cross-sectional study was conducted at Rehman Medical Institute, Peshawar, Pakistan from September 2019 to March 2020. Out of 390 critically ill patients, 200 cases of metabolic acidosis were selected by non-probability consecutive sampling technique. Measured and calculated bicarbonate values were obtained through Cobas-c 501© (Roche) using enzymatic method and Cobas-b 221© (Roche) blood gas analyzer respectively. Statistical analysis was done by using SPSS-23. RESULTS: Normal anion gap metabolic acidosis (NAG-MA) and high anion gap metabolic acidosis (HAG-MA) based on calculated bicarbonate levels was observed in 57 (28.5%) and 143 (71.5%) cases as compared to 55 (27.5%) and 145 (72.5%) cases based on measured bicarbonate levels respectively (p>0.45). A significant correlation (r=0.888 and 0.656, r2=0.788 and 0.431) (p<.001) was found between mean values of NAG-MA and HAG-MA respectively, when each was calculated through both modalities of bicarbonate. On applying Bland Altman plot, bias was 1.45±2.89 and -2.14±3.87mmol/L, Upper limit of agreement (LOA) was 7.13 and 5.46 for NAG-MA and HAG-MA, while lower LOA was -4.23 and -9.74 for NAG-MA and HAG-MA respectively. According to the model Bland Altman plot and Story & Postuie criteria, bias and the levels of agreement were not appropriate to conclude that both entities of anion gap could be used interchangeably. CONCLUSION: Normal and high anion gap metabolic acidosis estimated by measured and calculated bicarbonate cannot be used interchangeably in critically ill patients.

Euglycemic diabetic ketoacidosis induced by sodium-glucose cotransporter 2 inhibitor in the setting of prolonged fasting: a case report

BackgroundWe describe a case report of a patient with type 2 diabetes on sodium-glucose cotransporter 2 inhibitor and metformin therapy fasting for Ramadan (a holy month observed in the Islamic nation) diagnosed with euglycemic diabetic ketoacidosis.Case presentationThe patient was a 51-year-old Moroccan male with history of type 2 diabetes mellitus on dapagliflozin and metformin. He presented with abdominal pain, vomiting, loss of appetite, and shortness of breath. He observed Ramadan month by fasting an average of 14 hours daily for 30 days. The patient was admitted with severe metabolic acidosis with a high anion gap and positive ketonuria in the setting of serum glucose of 13.5 mmol/L (243 mg/dL).The patient was rehydrated and started on insulin infusion according to the diabetic ketoacidosis protocol following the diagnosis of euglycemic diabetic ketoacidosis.ConclusionDapagliflozin is associated with euglycemic diabetic ketoacidosis in the setting of prolonged fasting. Counseling and possible medication adjustment should be added to clinical practice in those planning to decrease caloric intake through dedicated fasting including Ramadan or weight-loss-directed behavioral modifications, especially if taking sodium-glucose cotransporter 2 inhibitors.

Assessing the Oxidative Stability of Anion Exchange Membranes in Oxygen Saturated Aqueous Alkaline Solutions

While anion exchange membrane water electrolyzers show promise as a source of green hydrogen using low-temperatures and non-platinum group metal catalysts, many concerns must be addressed. A primary challenge for the development of high-performance anion exchange membrane water electrolyzers is the fabrication of a stable membrane that will be able to survive long-term stability test while maintaining high anion conductivity, which is a necessity for a durable water electrolyzer. This method will present a standardized protocol that can be used by researchers to assess the quality of their AEM materials and be able to provide insight into how materials may be degrading and how to improve the quality of AEMs. Using Mohr or Volhard titration to measure ion-exchange capacity, EIS to determine the ionic conductivity, NMR and FTIR to understand the extent of membrane degradation over time, and mechanical analyzers to determine the strength of their AEMs, this standardized protocol will guide researchers to determining and improving upon the long-term durability and performance of their AEM materials.

Methanol Intoxication After Suicidal Ingestion of Liquid Rodenticides: A Report of Two Cases.

Methanol is highly toxic to humans. Although methanol poisoning is not uncommon in developing countries, poisoning caused by ingestion of commercial products containing undeclared methanol has rarely been reported. Herein, we describe two patients who experienced methanol poisoning after ingestion of liquid rodenticides. A 39-year-old woman attempted suicide by ingesting liquid rodenticide which contained bromadiolone. She developed high anion gap metabolic acidosis and coagulopathy. Methanol poisoning was confirmed 20 hours later. She received oral ethanol therapy and hemodialysis. Vitamin K1 was also administered. She did not develop any hemorrhage or visual impairment and was discharged after 11 days. The rodenticide sample was tested and found to have a methanol concentration of 324 g/L. In another case, a 62-year-old man ingested the same brand of rodenticide. Laboratory data showed mild metabolic acidosis with an increased osmol gap, suggestive of methanol poisoning. He received hemodialysis and eventually recovered without sequelae. Liquid rodenticide may contain methanol as a solvent. Ingestion of a methanol-containing commercial product without a clear label can result in a considerable delay in diagnosis and management. Methanol poisoning should be considered for patients who present with unexplained metabolic acidosis following exposure to liquid rodenticides or other liquid commercial products.

Relationship between seizures and metabolic acidosis: a prospective observational study

Objective: To assess changes in blood gas parameters, such as pH, partial carbon dioxide pressure (PaCO2), bicarbonate (HCO3), base deficit, and lactate values, in patients who present to the emergency care unit after a seizure. Methods: This is a prospective study on patients who suffered a generalized tonic-clonic seizure. The demographic and biochemical data of the patients and their blood gas parameters were recorded both at the time of presentation to the emergency department and during the follow-up examination. Results: A total of 68 patients were included in the study. Among the patients, 60.3% (41) were male. The median age of the patients was 43 years (IQR: 29-65.25). The median initial lactate value was 5.7 mmol/L (25th and 75th percentiles: 3.5–8.5 mmol/L). The median follow-up lactate value was 1.8 mmol/L (25th and 75th percentiles: 1.1–2.8 mmol/L). The statistical analysis of the blood gas parameters revealed a statistically significant difference in the pH, PaCO2, base deficit, and lactate values between the initial and follow-up evaluations (P<0.001). Conclusion: The results of our study suggest that metabolic acidosis with high anion gap may develop due to the increase in the lactate levels as a result of a tonic-clonic seizure.

High-Efficiency Production of Auricularia polytricha Polysaccharides Through Yellow Slurry Water Fermentation and Its Structure and Antioxidant Properties.

Yellow slurry water is a kind of nutrient-rich wastewater of tofu. Firstly, the medium of yellow slurry was optimized. Then, APP40, APP60, and APP80 were obtained by sedimentation with different concentration of ethanol (40, 60, and 80%). The physicochemical properties and primary structures of the three polysaccharides were studied by high performance anion exchange chromatography (HPAEC), high performance gel filtration chromatography (HPGFC), scanning electron microscope (SEM), atomic force microscope (AFM), and Fourier transform infrared (FT-IR) spectrometer. Finally, the effects of three polysaccharides on antioxidation activity were studied. According to the experimental optimization the results, the biomass and the production of Auricularia polytricha Polysaccharides (APPS) reached the peak, and they were 13.5 ± .655 and 9.42 ± .253 g/L (p < .05). The SEM and the AFM showed that the height of APP80 gradually increased from 31.1 to 46.7 nm and from APP40 to APP80. The particle size of APP80 increased, the pores decrease or even disappear, and the molecules begin to aggregate. The FT-IR spectrum analysis showed that the three polysaccharides possessed key functional groups. The carbohydrate content of APP40, APP60, and APP80 was 20.2, 34.25, and 31.73%. The molecular weights of APP40, APP60, and APP80 are 9.462 × 104, 8.742 × 104, and 8.091 × 104 Da, respectively. The three polysaccharides were composed of rhamnose, galactose, glucose, mannose, and xylose but with different molar ratio. APP80 showed strong reducing ability and scavenging activity of 2,2–diphenyl–1–picrylhydrazyl (DPPH) and hydroxyl radicals through antioxidant activities evaluated in vitro. This study introduces a way for the effective use of yellow slurry water.

The plasma and urine mineral status of lambs offered diets of perennial wheat or annual wheat, with or without lucerne

The development of perennial wheat is proposed to increase resource-use efficiency and sustainability of crop production. Annual dual-purpose winter wheat and perennial wheat offer grazing potential, however they both have mineral imbalances due to excess forage K and deficient Na, which may lead to metabolic diseases such as hypocalcaemia and hypomagnesaemia. Notwithstanding a low forage Na concentration, it was hypothesised that the addition of forage lucerne (alfalfa), high in forage Ca and Mg, may overcome calcium and magnesium deficiencies of the wheat varieties. A pen feeding study was conducted using 10-month-old Poll Dorset × Merino ewe lambs (46.4 ± 1.8 kg) to test the effect on plasma and urine mineral status with the addition of lucerne to perennial wheat or annual wheat forage. The lambs (n = 48) were individually fed one of four diets, including perennial wheat (PW), annual wheat (W), perennial wheat + lucerne (alfalfa) (PW + L) or annual wheat + lucerne (W + L) and feed intake was calculated daily. Individual blood and urine sampling commenced on entry to the pens and were repeated at 7-day intervals for 3 further weeks. The addition of lucerne increased the dietary supply of Ca, Mg and Na and decreased K and P. When compared to W, PW offered more Ca, Mg, K, and less Na and P. There were mineral intake differences over time (P < 0.001) for all minerals. All diets offered high dietary cation anion difference (45.0 – 94.9), K: (Na + Mg) (7.3 – 12.8), K: Na (305 – 1137) ratios, while the addition of lucerne increased the Ca: P ratio and improved the K: (Mg + Ca) (Tetany index). Plasma Mg, Na, K and P declined significantly throughout the study, under all diets, to varying degrees. In Week 1, plasma Mg was significantly lower in PW lambs when compared to all other diets, but no further diet effects were observed thereafter. By contrast, plasma Ca increased throughout the study, but without dietary effects. The urinary excretion of Mg was higher with the addition of lucerne in the PW + L and W + L diets after 1-week, although this effect declined in subsequent weeks. The excretion of Ca, Na and P was very low in urine and decreased, while K excretion increased during the study. Taken together the results indicate that the greater dietary intake of Ca, Mg and Na due to the addition of lucerne was insufficient to overcome the primary mineral imbalance of high dietary K and low Na in the cereal forages. Furthermore, the addition of lucerne to the diet further decreased P intake and greatly increased the Ca: P ratio. Our calculations suggest lambs grazing any of the diets in the present study still required supplementation with Na and Mg, but the addition of lucerne alleviated the need for Ca supplementation. The need for supplementation with a source of dietary P requires further investigation.

Template-free synthesis of an eco-friendly flower-like Mg/Al/Fe-CLDH for efficient arsenate removal from aqueous solutions

• A novel flower-like Mg/Al/Fe-CLDH was synthesized for As(V) removal. • Mg/Al/Fe-CLDH exhibited excellent acid and alkali resistance and reusability. • The maximum adsorption capacity of the Mg/Al/Fe-CLDH was 70.7 mg/g. • As(V) ions intercalated into the interlayer region to reconstruct the hydrotalcite. Mg/Al-LDH is widely used in the removal of aqueous pollutants due to the large surface and high anion exchange capacity, but the traditional Mg/Al-LDH for arsenic removal has a narrow range of pH application. The present study focused on the modifying of the lamellar Mg/Al-LDH to synthesize flower-like nanoparticles for arsenate removal in a wide pH range. Results showed that Mg/Al/Fe-CLDH (calcined Mg/Al/Fe-LDH) exhibited an extremely high arsenate removal efficiency (e.g., reducing As(V) from 10 mg/L to 1 µg/L) in a wide pH range (2–12). Furthermore, it can keep excellent removal efficiency for arsenate under a complex anions environment (co-existing with CO 3 2− , SO 4 2− , PO 4 3− , and F − ), and maintain 80% removal efficiency for arsenate after 4 regeneration cycles. SEM, XRD, and XPS results unveiled the following enhancing mechanism for arsenate removal by using this modified Mg/Al-LDH: 1) partial content of ferric ions were successfully insert into the layers of Mg/Al-LDH and substituted by aluminium ions, which produce more affiliative sites for arsenate and expand its feasibility in a wide pH ranges; 2) the flower-like structures facilitate to offer more adsorption sites for arsenate due to its larger specific surface area. In brief, this flower-like Mg/Al/Fe-CLDH has great application potential for eco-friendly purity of arsenate from complicated industrial wastewater.

POS-092 SGLT2 INHIBITOR – INDUCED EUGLYCEMIC DIABETIC KETOACIDOSIS IN GUILLAIN-BARRE SYNDROME: A CASE REPORT

Introduction: Euglycemic diabetic ketoacidosis (EuDKA) is a rare but increasingly reported serious adverse effect of SGLT2 inhibitors. There is not much published literature on the incidence of EuDKA and the factors associated with it. Though SGLT2 inhibitors were introduced as glucose lowering agents, recent trials have demonstrated their favourable cardiovascular outcome in heart failure and ability to retard progression of proteinuric kidney disease, including in non-diabetics. Hence use of this class of drugs is anticipated to increase exponentially, given the combined high global burden of diabetes, coronary artery disease and chronic kidney disease. As we embark to use the SGLT2 inhibitors in different clinical scenarios, it becomes imperative to report their adverse effects encountered in uncommon clinical conditions as well. Case history: A 42-year-old gentleman with history of type 2 diabetes mellitus for 15 years and coronary artery disease, presented with difficulty in climbing stairs and walking for 5 days with progressive difficulty in getting up from bed. He did not have past history of covid infection and had been immunised with 1 dose of covid vaccine. On examination, patient had normal hemodynamics. There was flaccid quadriparesis with areflexia and truncal muscle weakness. Nerve conduction study confirmed acute demyelinating polyradiculoneuropathy. His baseline laboratory investigations revealed normal renal parameters but metabolic acidosis was noted at the time of admission. Patient was started on iv immunoglobulin 2mg/kg and the motor weakness improved from grade 2/5 to 4/5. However, the high anion gap metabolic acidosis worsened over the next 4 days and patient developed acidotic breathing. His sugars were within normal limits and the patient was on metformin, glimeperide, vildagliptin, voglibose and dapagliflozin. As blood lactate levels were normal with urine acetone positivity, euglycemic diabetic ketoacidosis secondary to SGLT2 inhibitor was suspected and all the oral hypoglycemic agents were stopped. He was started on hydration and insulin infusion. After 48 hours of stopping dapagliflozin, acidosis resolved completely and the patient was reintroduced back on the other 4 class drugs. At follow-up, there was no recurrence of acidosis and patient was able to walk with support and physiotherapy. Discussion: SGLT2 inhibitors cause glycosuria and directly induce glucagon release from pancreas. Combined with insulin deficiency, this results in lipolysis, fatty acid oxidation and ketogenesis. They also cause increased renal reabsorption of ketone bodies. The precipitating factors for EuDKA identified so far include abrupt reduction in insulin dosage, reduced oral intake, infections, surgery, excess alcohol use, volume depletion, type 1 diabetes and heavy physical exercise. This is the first reported case of SGLT2 inhibitor-induced EuDKA in a patient with Guillain-Barre syndrome. As symptoms of dehydration may not be significant due to lack of hyperglycemia in EuDKA, there may be a delay in the diagnosis of this complication. Conclusion: The possibility of EuDKA to be kept in mind while evaluating metabolic acidosis in a diabetic patient on SGLT2 inhibitors. Temporarily withholding the SGLT2 inhibitors during an intercurrent illness will prevent the occurrence of the above serious adverse effect.

POS-091 THE PERFECT STORM FOR PYROGLUTAMIC ACIDOSIS: AN UNDER-RECOGNISED CAUSE OF HAGMA

Metabolic acidosis is defined as reduced blood pH, accumulation of hydrogen ions (H+) and decreased level of bicarbonate ions (HCO3-). It can be categorised into either normal anion gap (NAGMA) or high anion gap (HAGMA) by using the formula [Na+ - (Cl- + HCO3-)]. There are 2 classical mnemonics (KUSMALE and MUDPILES) to remember the causes of the HAGMA. However, a newer mnemonic GOLDMARK is recommended as we have identified more relevant conditions that can contribute to HAGMA. GOLDMARK signifies Glycols (ethylene and propylene), Oxoproline, L-lactate, D-lactate, Methanol, Aspirin, Renal failure, and Ketoacidosis.

Elovl2-Ablation Leads to Mitochondrial Membrane Fatty Acid Remodeling and Reduced Efficiency in Mouse Liver Mitochondria

The fatty acid elongase elongation of very long-chain fatty acids protein 2 (ELOVL2) controls the elongation of polyunsaturated fatty acids (PUFA) producing precursors for omega-3, docosahexaenoic acid (DHA), and omega-6, docosapentaenoic acid (DPAn-6) in vivo. Expectedly, Elovl2-ablation drastically reduced the DHA and DPAn-6 in liver mitochondrial membranes. Unexpectedly, however, total PUFAs levels decreased further than could be explained by Elovl2 ablation. The lipid peroxidation process was not involved in PUFAs reduction since malondialdehyde-lysine (MDAL) and other oxidative stress biomarkers were not enhanced. The content of mitochondrial respiratory chain proteins remained unchanged. Still, membrane remodeling was associated with the high voltage-dependent anion channel (VDAC) and adenine nucleotide translocase 2 (ANT2), a possible reflection of the increased demand on phospholipid transport to the mitochondria. Mitochondrial function was impaired despite preserved content of the respiratory chain proteins and the absence of oxidative damage. Oligomycin-insensitive oxygen consumption increased, and coefficients of respiratory control were reduced by 50%. The mitochondria became very sensitive to fatty acid-induced uncoupling and permeabilization, where ANT2 is involved. Mitochondrial volume and number of peroxisomes increased as revealed by transmission electron microscopy. In conclusion, the results imply that endogenous DHA production is vital for the normal function of mouse liver mitochondria and could be relevant not only for mice but also for human metabolism.