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Nature Communications Jan 2024Industrial hydrogen peroxide (HO) is synthesized using carbon-intensive H gas production and purification, anthraquinone hydrogenation, and anthrahydroquinone oxidation....
Industrial hydrogen peroxide (HO) is synthesized using carbon-intensive H gas production and purification, anthraquinone hydrogenation, and anthrahydroquinone oxidation. Electrochemical hydrogenation (ECH) of anthraquinones offers a carbon-neutral alternative for generating HO using renewable electricity and water instead of H gas. However, the HO formation rates associated with ECH are too low for commercialization. We report here that a membrane reactor enabled us to electrochemically hydrogenate anthraquinone (0.25 molar) with a current efficiency of 70% at current densities of 100 milliamperes per square centimeter. We also demonstrate continuous HO synthesis from the hydrogenated anthraquinones over the course of 48 h. This study presents a fast rate of electrochemically-driven anthraquinone hydrogenation (1.32 ± 0.14 millimoles per hour normalized per centimeter squared of geometric surface of electrode), and provides a pathway toward carbon-neutral HO synthesis.
PubMed: 38278793
DOI: 10.1038/s41467-024-44741-1 -
The Western Journal of Emergency... Nov 2023Euglycemic diabetic ketoacidosis (DKA) (glucose <250 milligrams per deciliter (mg/dL) has increased in recognition since introduction of sodium-glucose co-transporter 2...
INTRODUCTION
Euglycemic diabetic ketoacidosis (DKA) (glucose <250 milligrams per deciliter (mg/dL) has increased in recognition since introduction of sodium-glucose co-transporter 2 (SGLT2) inhibitors but remains challenging to diagnose and manage without the hyperglycemia that is otherwise central to diagnosing DKA, and with increased risk for hypoglycemia with insulin use. Our objective was to compare key resource utilization and safety outcomes between patients with euglycemic and hyperglycemic DKA from the same period.
METHODS
This is a retrospective review of adult emergency department patients in DKA at an academic medical center. Patients were included if they were >18 years old, met criteria for DKA on initial laboratories (pH ≤7.30, serum bicarbonate ≤18 millimoles per liter [mmol/L], anion gap ≥10), and were managed via a standardized DKA order set. Patients were divided into euglycemic (<250 milligrams per deciliter [mg/dL]) vs hyperglycemic (≥250 mg/dL) cohorts by presenting glucose. We extracted and analyzed patient demographics, resource utilization, and safety outcomes. Etiologies of euglycemia were obtained by manual chart review. For comparisons between groups we used independent-group -tests for continuous variables and chi-squared tests for binary variables, with alpha 0.05.
RESULTS
We identified 629 patients with DKA: 44 euglycemic and 585 hyperglycemic. Euglycemic patients had milder DKA on presentation (higher pH and bicarbonate, lower anion gap; < 0.05) and lower initial glucose (195 vs 561 mg/dL, < 0.001) and potassium (4.3 vs 5.3 mmol/L, < 0.001). Etiologies of euglycemia were insulin use prior to arrival (57%), poor oral intake with baseline insulin use (29%), and SGLT2 inhibitor use (14%). Mean time on insulin infusion was shorter for those with euglycemic DKA: 13.5 vs 19.4 hours, = 0.003. Mean times to first bicarbonate >18 mmol/L and first long-acting insulin were similar. Incidence of hypoglycemia (<70 mg/dL) while on insulin infusion was significantly higher for those with euglycemic DKA (18.2 vs 4.8%, = 0.02); incidence of hypokalemia (<3.3 mmol/L) was 27.3 vs 19.1% ( = 0.23).
CONCLUSION
Compared to hyperglycemic DKA patients managed in the same protocolized fashion, euglycemic DKA patients were on insulin infusions 5.9 hours less, yet experienced hypoglycemia over three times more frequently. Future work can investigate treatment strategies for euglycemic DKA to minimize adverse events, especially iatrogenic hypoglycemia.
Topics: Adult; Humans; Adolescent; Diabetic Ketoacidosis; Bicarbonates; Insulin; Hypoglycemia; Glucose; Diabetes Mellitus
PubMed: 38165186
DOI: 10.5811/westjem.60361 -
Medical Science Monitor : International... Jul 2023BACKGROUND Human visceral adipose tissue (VAT), now identified as an endocrine organ, plays a significant role in impaired fasting glucose and diabetes through the...
BACKGROUND Human visceral adipose tissue (VAT), now identified as an endocrine organ, plays a significant role in impaired fasting glucose and diabetes through the deregulated metabolism and adipogenesis of visceral adipocytes in obesity. Our study focuses on exploring the link between inflammation, oxidative stress, and glucose metabolism-associated genes with corresponding miRNAs in human visceral adipocytes and VAT from individuals with glucose metabolism disorders. MATERIAL AND METHODS We examined the expression of ATM, NFKB1, SOD2, INSR, and TIGAR, along with their related miRNAs using PCR, in two contexts:1 - During the three-stage visceral adipogenesis under normal glucose levels (5.5 millimoles), intermittent, and chronic hyperglycemia (30 millimoles).2 - In visceral adipose tissue from subjects (34 F, 18 M) with normal glucose metabolism, impaired fasting glucose, and type 2 diabetes mellitus. RESULTS Both chronic and intermittent hyperglycemia similarly influenced ATM, NFKB1, TIGAR, SOD2, INSR gene expression in visceral adipocytes, with corresponding changes in a few tested miRNAs (eg, let-7g-5p, miR-145-5p, miR-21-5p). Anthropometric and biochemical parameters led us to focus on female subjects. Our results showed transactivation of NFKB1, TIGAR, miR-10b-5p, miR-132-3p, miR-20a-5p, miR-21-5p, and miR-26a-5p exclusively in type 2 diabetes mellitus. Upregulated molecules (excluding miR-10b-5p and miR-20a-5p) positively correlated with glucose metabolism markers. CONCLUSIONS The genes studied may undergo miRNA interferences and hyperglycemic memory in visceral adipocytes under hyperglycemic conditions. VAT from women with type 2 diabetes mellitus, but not with impaired fasting glucose, showed transactivated miRNAs and a molecular dysregulation of TIGAR and NFKB1, possibly enhancing inflammation, oxidative stress, and disrupted glucose metabolism. These findings highlight the epigenetic and molecular disturbances in VAT related to glucose metabolism abnormalities. However, additional research is necessary to further understand their biological significance.
Topics: Humans; Female; MicroRNAs; Diabetes Mellitus, Type 2; Intra-Abdominal Fat; Inflammation; Hyperglycemia; Glucose; Oxidative Stress; Adipose Tissue
PubMed: 37422695
DOI: 10.12659/MSM.939299 -
Surgical Endoscopy Oct 2023In metabolic surgery, hemorrhage is the most common major complication. This study investigated whether peroperative administration of tranexamic acid (TXA) reduced the... (Randomized Controlled Trial)
Randomized Controlled Trial
INTRODUCTION
In metabolic surgery, hemorrhage is the most common major complication. This study investigated whether peroperative administration of tranexamic acid (TXA) reduced the risk of hemorrhage in patients undergoing laparoscopic sleeve gastrectomy (SG).
METHODS
In this double-blind randomized controlled trial, patients undergoing primary SG in a high-volume bariatric hospital were randomized (1:1) to receive 1500-mg TXA or placebo peroperatively. Primary outcome measure was peroperative staple line reinforcement using hemostatic clips. Secondary outcome measures were peroperative fibrin sealant use and blood loss, postoperative hemoglobin, heart rate, pain, major and minor complications, length of hospital stay (LOS), side effects of TXA (i.e., venous thrombotic event (VTE)) and mortality.
RESULTS
In total, 101 patients were analyzed and received TXA (n = 49) or placebo (n = 52). There was no statistically significant difference in hemostatic clip devices used in both groups (69% versus 83%, p = 0.161). TXA administration showed significant positive changes in hemoglobin levels (millimoles per Liter; 0.55 versus 0.80, p = 0.013), in heart rate (beats per minute; -4.6 versus 2.5; p = 0.013), in minor complications (Clavien-Dindo ≤ 2, 2.0% versus 17.3%, p = 0.016), and in mean LOS (hours; 30.8 versus 36.7, p = 0.013). One patient in the placebo-group underwent radiological intervention for postoperative hemorrhage. No VTE or mortality was reported.
CONCLUSION
This study did not demonstrate a statistically significant difference in use of hemostatic clip devices and major complications after peroperative administration of TXA. However, TXA seems to have positive effects on clinical parameters, minor complications, and LOS in patients undergoing SG, without increasing the risk of VTE. Larger studies are needed to investigate the effect of TXA on postoperative major complications.
Topics: Humans; Tranexamic Acid; Antifibrinolytic Agents; Postoperative Hemorrhage; Double-Blind Method; Blood Loss, Surgical; Administration, Intravenous
PubMed: 37400687
DOI: 10.1007/s00464-023-10232-5 -
Science Advances Aug 2023Porous physisorbents are attractive candidates for selective capture of trace gas or volatile compounds due to their low energy footprints. However, many physisorbents...
Porous physisorbents are attractive candidates for selective capture of trace gas or volatile compounds due to their low energy footprints. However, many physisorbents suffer from insufficient sorbate-sorbent interactions, resulting in low uptake or inadequate selectivity when gases are present at trace levels. Here, we report a strategy of programmed fluorine binding engineering in anion-pillared metal-organic frameworks to maximize CH binding affinity for benchmark trace CH capture from CH. A robust material (ZJU-300a) was elaborately designed to provide multiple-site fluorine binding model, resulting in an ultrastrong CH binding affinity. ZJU-300a exhibits a record-high CH uptake of 3.23 millimoles per gram (at 0.01 bar and 296 kelvin) and one of the highest CH/CH selectivity (1672). The adsorption binding of CH and CH was visualized by gas-loaded ZJU-300a structures. The separation capacity was confirmed by breakthrough experiments for 1/99 CH/CH mixtures, affording the maximal dynamic selectivity (264) and CH productivity of 436.7 millimoles per gram.
PubMed: 37540740
DOI: 10.1126/sciadv.adh0135 -
ChemSusChem Feb 2024The first enantioselective reduction of 2-substituted cyclic imines to the corresponding amines (pyrrolidines, piperidines, and azepines) by imine reductases (IREDs) in...
The first enantioselective reduction of 2-substituted cyclic imines to the corresponding amines (pyrrolidines, piperidines, and azepines) by imine reductases (IREDs) in non-conventional solvents is reported. The best results were obtained in a glycerol/phosphate buffer 1 : 1 mixture, in which heterocyclic amines were produced with full conversions (>99 %), moderate to good yields (22-84 %) and excellent S-enantioselectivities (up to >99 % ee). Remarkably, the process can be performed at a 100 mM substrate loading, which, for the model compound, means a concentration of 14.5 g L . A fed-batch protocol was also developed for a convenient scale-up transformation, and one millimole of substrate 1 a was readily converted into 120 mg of enantiopure amine (S)-2 a with a remarkable 80 % overall yield. This aspect strongly contributes to making the process potentially attractive for large-scale applications in terms of economic and environmental sustainability for a good number of substrates used to produce enantiopure cyclic amines of high pharmaceutical interest.
Topics: Oxidoreductases; Imines; Solvents; Stereoisomerism; Amines
PubMed: 37751248
DOI: 10.1002/cssc.202301243 -
Nature Communications Jan 2024The direct oxidation of methane to methanol under mild conditions is challenging owing to its inadequate activity and low selectivity. A key objective is improving the...
The direct oxidation of methane to methanol under mild conditions is challenging owing to its inadequate activity and low selectivity. A key objective is improving the selective oxidation of the first carbon-hydrogen bond of methane, while inhibiting the oxidation of the remaining carbon-hydrogen bonds to ensure high yield and selectivity of methanol. Here we design ultrathin PdAu nanosheets and revealed a volcano-type relationship between the binding strength of hydroxyl radical on the catalyst surface and catalytic performance using experimental and density functional theory results. Our investigations indicate a trade-off relationship between the reaction-triggering and reaction-conversion steps in the reaction process. The optimized PdAu nanosheets exhibits a methanol production rate of 147.8 millimoles per gram of Pd per hour, with a selectivity of 98% at 70 °C, representing one of the most efficient catalysts for the direct oxidation of methane to methanol.
PubMed: 38233390
DOI: 10.1038/s41467-024-44839-6 -
Optics Express Mar 2024While bright terahertz sources are used to perform nonlinear experiments, they can be advantageous for high-precision linear measurements of opaque samples. By placing...
While bright terahertz sources are used to perform nonlinear experiments, they can be advantageous for high-precision linear measurements of opaque samples. By placing the sample away from the focus, nonlinearities can be suppressed, and sizeable amounts of transmitted radiation detected. Here, this approach is demonstrated for a 0.5 mm thick layer of liquid water in a static sample holder. Variations of the index of refraction as small as (7 ± 2) · 10 were detected at 0.58 THz for an aqueous salt solution containing ten millimoles of sodium chloride. To my knowledge, this precision is unprecedented in time-domain spectroscopy studies of diluted aqueous systems or other optically thick and opaque materials.
PubMed: 38570962
DOI: 10.1364/OE.510393 -
Life (Basel, Switzerland) Oct 2023The aim of the study was to perform a comprehensive fundamental analysis of the factors of inflammation, oxidative stress, fibrosis, myocardial dysfunction, ischemia and...
The aim of the study was to perform a comprehensive fundamental analysis of the factors of inflammation, oxidative stress, fibrosis, myocardial dysfunction, ischemia and omega-3 index associated with postoperative atrial fibrillation (POAF) after coronary artery bypass graft (CABG) surgery in patients with coronary artery disease. The study involved 158 patients who were admitted to the hospital to undergo CABG surgery. Patients were divided into two groups: group 1 comprised 111 patients without POAF (82% males, median age-62.0 (56.0; 66.0) years), and group 2 comprised 47 patients with POAF (84.4% males, median age-65.0 (61.0; 70.0) years). POAF occurred 5.2 (2.0; 7.0) days after CABG. In all the patients, we evaluated laboratory tests before and 3-4 days after CABG. All the patients also underwent echocardiography. According to results of multifactorial regression analysis, the odds ratio of POAF development for left atrial diameter >41 mm was 4.3 (95% confidence interval (CI) 2.0-9.7, < 0.001), interleukin (IL)-6 postoperative levels >22.07 pg/mL-3.0 (95% CI 1.4-8.2, = 0.006), IL-8 postoperative levels >9.67 pg/mL-2.3 (95% CI 1.2-7.3, = 0.006), superoxide dismutase postoperative levels in plasma >1100.5 U/g-3.2 (95% CI 1.4-9.2, = 0.03), glutathione postoperative levels ≤0.194 micromole/g of hemoglobin-1.9 (95% CI 1.2-6.3, < 0.001), glutathione peroxidase postoperative levels ≤17.36 millimole/g of hemoglobin-2.2 (95% CI 1.1-8.2, < 0.001), glutathione reductase postoperative levels ≤2.99 millimole/g of hemoglobin-2.3 (95% CI, 1.1-5.7, < 0.001), malondialdehyde postoperative levels >1.25 micromole/g of hemoglobin-2.0 (95% CI, 1.2-7.9, < 0.001), NO postoperative levels in plasma >36.4 micromole/L-1.5 (95% CI, 1.1-5.9, < 0.001) and omega-3 index ≤1.59%-2.6 (95% CI 1.5-9.1, < 0.001). Our study showed that increased left atrial diameter, high postoperative levels of inflammatory factors, oxidative stress, fibrosis indicators and omega-3 index were associated with POAF in patients who underwent CABG.
PubMed: 37895417
DOI: 10.3390/life13102035