RESUMO
This study aimed to evaluate the effect of chemical gasification and HEPES as alternative systems to pH control during in vitro maturation on bovine oocytes competence. Groups of 20 bovine cumulus oocytes complexes (COCs) were randomly distributed and cultured for 24 h in one of the following experimental groups: (i) chemical reaction (ChRG) system: CO2 generated from sodium bicarbonate and citric acid reaction (ii) culture media TCM-HEPES (HEPES-G); and (iii) control group (CNTG) in conventional incubator. After in vitro maturation (IVM), the COCs were in vitro fertilized (IVF), and in vitro cultivated (IVC) in a conventional incubator. We evaluated oocyte nuclear maturation, cleavage and blastocyst rates, in addition to the relative mRNA expression of BAX, BMP-15, AREG and EREG genes in oocytes and cumulus cells. The proportion of oocytes in metaphase II was higher in CNTG and ChRG (77.57% and 77.06%) than in the HEPES-G (65.32%; p = .0408 and .0492, respectively). The blastocyst production was similar between CNTG and ChRG (26.20% and 28.47%; p = .4232) and lower (p = .001) in the HEPES-G (18.71%). The relative mRNA expression of BAX gene in cumulus cells was significantly higher (p = .0190) in the HEPES-G compared to the CNTG. Additionally, the relative mRNA expression of BMP-15 gene was lower (p = .03) in oocytes from HEPES-G compared to the CNTG. In conclusion, inadequate atmosphere control has a detrimental effect on oocyte maturation. Yet, the use of chemical gasification can be an efficient alternative to bovine COCs cultivation.
Assuntos
Fertilização in vitro , Técnicas de Maturação in Vitro de Oócitos , Oócitos , Animais , Bovinos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos/efeitos dos fármacos , Fertilização in vitro/veterinária , Feminino , Meios de Cultura , Blastocisto/efeitos dos fármacos , Células do Cúmulo/efeitos dos fármacos , Dióxido de Carbono/farmacologia , Bicarbonato de Sódio/farmacologia , Ácido Cítrico/farmacologia , Técnicas de Cultura Embrionária/veterináriaRESUMO
The objectives of this study were to estimate genetic parameters for citric acid content (CA) and lactic acid content (LA) in sheep milk and to identify the associated candidate genes in a New Zealand dairy sheep flock. Records from 165 ewes were used. Heritability estimates based on pedigree records for CA and LA were 0.65 and 0.33, respectively. The genetic and phenotypic correlations between CA and LA were strong-moderate and negative. Estimates of genomic heritability for CA and LA were also high (0.85, 0.51) and the genomic correlation between CA and LA was strongly negative (-0.96 ± 0.11). No significant associations were found at the Bonferroni level. However, one intragenic SNP in C1QTNF1 (chromosome 11) was associated with CA, at the chromosomal significance threshold. Another SNP associated with CA was intergenic (chromosome 15). For LA, the most notable SNP was intragenic in CYTH1 (chromosome 11), the other two SNPs were intragenic in MGAT5B and TIMP2 (chromosome 11), and four SNPs were intergenic (chromosomes 1 and 24). The functions of candidate genes indicate that CA and LA could potentially be used as biomarkers for energy balance and clinical mastitis. Further research is recommended to validate the present results.
Assuntos
Ácido Cítrico , Estudo de Associação Genômica Ampla , Ácido Láctico , Leite , Polimorfismo de Nucleotídeo Único , Animais , Leite/química , Feminino , Ovinos/genética , Nova Zelândia , Polimorfismo de Nucleotídeo Único/genética , Ácido Cítrico/análise , Ácido Láctico/metabolismoRESUMO
AIM: This study aimed to compare the effectiveness of initial irrigation with sodium hypochlorite (NaOCl) and final irrigation with QMix, 40% citric acid, and 17% ethylenediaminetetraacetic acid (EDTA) on smear layer removal and dentin erosion. METHODOLOGY: Forty extracted human mandibular premolar teeth were randomly divided into four groups (n = 10) according to the type of final irrigants used: 17% EDTA, QMix, citric acid, and control (normal saline). Canals were mechanically prepared using ProTaper Next instruments to an apical size of X3. Subsequently, the roots were sectioned in a buccolingual direction. Scanning electron microscopy (SEM) was used to assess the presence of the smear layer and the amount of dentin erosion in the coronal, middle, and apical thirds of the root canals. RESULTS: In regards to smear layer removal, there was a significant difference between the control group and the other tested groups. Moreover, it was significantly higher in the coronal and middle thirds than in the apical third. However, there were no significant differences between the groups of EDTA, QMix, and citric acid. Concerning dentin erosion, citric acid produced significantly more dentin erosion than the other tested groups. CONCLUSION: Final irrigation with solutions had a higher ability to remove the smear layer in the coronal and middle thirds compared to the apical third. Of all the solutions tested, 40% citric acid had the most pronounced impact on dentin erosion, followed by 17% EDTA and QMix.
Assuntos
Ácido Cítrico , Dentina , Ácido Edético , Microscopia Eletrônica de Varredura , Irrigantes do Canal Radicular , Camada de Esfregaço , Hipoclorito de Sódio , Humanos , Irrigantes do Canal Radicular/farmacologia , Ácido Cítrico/farmacologia , Ácido Cítrico/química , Ácido Edético/química , Ácido Edético/farmacologia , Hipoclorito de Sódio/farmacologia , Dentina/efeitos dos fármacos , Dentina/ultraestrutura , Dente Pré-Molar/efeitos dos fármacos , Preparo de Canal Radicular/métodos , Irrigação Terapêutica/métodos , Biguanidas/farmacologia , Erosão Dentária , PolímerosRESUMO
Itaconic acid (IA) is one of the twelve high value-added platform compounds applied in various fields including coatings, adhesives, plastics, resins, and biofuels. In this study, we established a one-pot catalytic synthesis system for IA from citric acid based on the engineered salt-tolerant bacterial strain Halomonas bluephagenesis TDZI-08 after investigating factors that hindered the process and optimizing the carbon source, nitrogen source, inducer addition time, and surfactant dosage. The open, non-sterile, one-pot synthesis with TDZI-08 in a 5 L fermenter achieved the highest IA titer of 40.50 g/L, with a catalytic yield of 0.68 g IA/g citric acid during the catalytic stage and a total yield of 0.42 g IA/g (citric acid+gluconic acid). The one-pot synthesis system established in this study is simple and does not need sterilization or aseptic operations. The findings indicate the potential of H. bluephagenesis for industrial production of IA.
Assuntos
Halomonas , Succinatos , Halomonas/metabolismo , Halomonas/genética , Succinatos/metabolismo , Engenharia Metabólica , Microbiologia Industrial , Ácido Cítrico/metabolismo , FermentaçãoRESUMO
CLINICAL RELEVANCE: Awareness of the causes of hypercalcemia is essential for timely diagnosis of calcium disorders and optimal treatment. Citrate is commonly used as an anticoagulant during continuous renal replacement therapy (CRRT). Accumulation of citrate in the systemic circulation during CRRT may induce several metabolic disturbances, including total hypercalcemia and ionized hypocalcemia. The aim of the present study is to increase awareness of citrate accumulation and toxicity as a cause of hypercalcemia by relating three cases and reviewing the pathophysiology and clinical implications. OBSERVATIONS: We utilized electronic health records to examine the clinical cases and outlined key studies to review the consequences of citrate toxicity and general approaches to management. CONCLUSIONS: Citrate toxicity is associated with high mortality. A safe threshold for tolerating hypercalcemia during citrate anticoagulation is not clearly defined, and whether citrate toxicity independently increases mortality has not been resolved. Greater attention to citrate toxicity as a cause of hypercalcemia may lead to earlier detection, help to optimize the management of systemic calcium levels, and foster interest in future clinical studies.
Assuntos
Anticoagulantes , Ácido Cítrico , Terapia de Substituição Renal Contínua , Hipercalcemia , Humanos , Hipercalcemia/induzido quimicamente , Hipercalcemia/etiologia , Anticoagulantes/efeitos adversos , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Terapia de Substituição Renal Contínua/métodos , Ácido Cítrico/efeitos adversos , Ácido Cítrico/administração & dosagem , Ácido Cítrico/uso terapêutico , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Cálcio/sangueRESUMO
Nanofibers show promise for wound healing by facilitating active agent delivery, moisture retention, and tissue regeneration. However, selecting suitable dressings for diverse wound types and managing varying exudate levels remains challenging. This study synthesized carbon quantum dots (CQDs) from citrate salt and thiourea using a hydrothermal method. The CQDs displayed antibacterial activity against Staphylococcus aureus and Escherichia coli. A nanoscaffold comprising gelatin, chitosan, and polycaprolactone (GCP) was synthesized and enhanced with silver nanoparticle-coated CQDs (Ag-CQDs) to form GCP-Q, while citrate addition yielded GCP-QC. Multiple analytical techniques, including electron microscopy, FT-IR spectroscopy, dynamic light scattering, UV-Vis, photoluminescence, X-ray diffraction, porosity, degradability, contact angle, and histopathology assessments characterized the CQDs and nanofibers. Integration of CQDs and citrate into the GCP nanofibers increased porosity, hydrophilicity, and degradability-properties favorable for wound healing. Hematoxylin and eosin staining showed accelerated wound closure with GCP-Q and GCP-QC compared to GCP alone. Overall, GCP-Q and GCP-QC nanofibers exhibit significant potential for skin tissue engineering applications.
Assuntos
Antibacterianos , Bandagens , Carbono , Ácido Cítrico , Escherichia coli , Nanofibras , Pontos Quânticos , Staphylococcus aureus , Cicatrização , Pontos Quânticos/química , Nanofibras/química , Cicatrização/efeitos dos fármacos , Carbono/química , Ácido Cítrico/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Animais , Quitosana/química , Poliésteres/química , Gelatina/química , Nanopartículas Metálicas/químicaRESUMO
Immunodetection of cardiac isoforms of troponin I (cTnI) and troponin T (cTnT) in blood samples is widely used for the diagnosis of acute myocardial infarction. The cardiac troponin complex (ITC-complex), comprising cTnI, cTnT, and troponin C (TnC), makes up a large portion of troponins released into the bloodstream after the necrosis of cardiomyocytes. However, the stability of the ITC-complex has not been fully investigated. This study aimed to investigate the stability of the ITC-complex in blood samples. A native ITC-complex was incubated in buffer solutions, serum, and citrate, heparin, or EDTA plasma at various temperatures. Western blotting and gel filtration were performed, and troponins were detected using specific monoclonal antibodies. The ITC-complex dissociated at 37 °C in buffers with or without anticoagulants, in citrate, heparin, and EDTA plasmas, and in serum, into a binary cTnI-TnC complex (IC-complex) and free cTnT. In plasma containing heparin and EDTA, the IC-complex further dissociated into free TnC and cTnI. No dissociation was found at 4 °C or at room temperature (RT) in all matrices within 24 h except for EDTA plasma. After incubation at 37 °C in EDTA plasma and serum, dissociation was accompanied by proteolytic degradation of both cTnI and cTnT. The presence of anti-troponin autoantibodies in the sample impeded dissociation of the ITC-complex. The ITC-complex dissociates in vitro to form the IC-complex and free cTnT at 37 °C but is mostly stable at 4 °C or RT. Further dissociation of the IC-complex occurs at 37 °C in plasmas containing heparin and EDTA.
Assuntos
Anticoagulantes , Troponina I , Troponina T , Anticoagulantes/farmacologia , Humanos , Troponina I/sangue , Troponina T/sangue , Troponina C/sangue , Ácido Edético/química , Ácido Edético/farmacologia , Heparina , Ácido CítricoRESUMO
Regional citrate anticoagulation use in intermittent hemodialysis is limited by the increased risk of metabolic complications due to faster solute exchanges than with continuous renal replacement therapies. Several simplifications have been proposed. The objective of this study was to validate a mathematical model of hemodialysis anticoagulated with citrate that was then used to evaluate different prescription scenarios on anticoagulant effectiveness (free calcium concentration in dialysis filter) and calcium balance. A study was conducted in hemodialyzed patients with a citrate infusion into the arterial line and a 1.25 mmol/L calcium dialysate. Calcium and citrate concentrations were measured upstream and downstream of the citrate infusion site and in the venous line. The values measured in the venous lines were compared with those predicted by the model using Bland and Altman diagrams. The model was then used with 22 patients to make simulations. The model can predict the concentration of free calcium, bound to citrate or albumin, accurately. Irrespective of the prescription scenario a decrease in free calcium below 0.4 mmol/L was obtained only in a fraction of the dialysis filter. A zero or slightly negative calcium balance was observed, and should be taken into account in case of prolonged use.
Assuntos
Anticoagulantes , Cálcio , Ácido Cítrico , Diálise Renal , Humanos , Diálise Renal/métodos , Anticoagulantes/administração & dosagem , Feminino , Masculino , Pessoa de Meia-Idade , Cálcio/metabolismo , Cálcio/sangue , Idoso , Modelos Teóricos , Simulação por ComputadorRESUMO
Rahnella aquatilis causes seafoods to spoil by metabolizing sulfur-containing amino acids and/or proteins, producing H2S in products. The type II secretion system (T2SS) regulates the transport of proteases from the cytoplasm to the surrounding environment and promotes bacterial growth at low temperatures. To prevent premature fish spoilage, new solutions for inhibiting the T2SS of bacteria should be researched. In this study, global transcriptome sequencing was used to analyze the spoilage properties of R. aquatilis KM05. Two of the mapped genes/coding sequences (CDSs) were matched to the T2SS, namely, qspF and gspE, and four of the genes/CDSs, namely, ftsH, rseP, ptrA and pepN, were matched to metalloproteases or peptidases in R. aquatilis KM05. Subinhibitory concentrations of citric (18 µM) and acetic (41 µM) acids caused downregulation of T2SS-related genes (range from - 1.0 to -4.5) and genes involved in the proteolytic activities of bacteria (range from - 0.5 to -4.0). The proteolytic activities of R. aquatilis KM05 in vitro were reduced by an average of 40%. The in situ experiments showed the antimicrobial properties of citric and acetic acids against R. aquatilis KM05; the addition of an acidulant to salmon fillets limited microbial growth. Citric and acetic acids extend the shelf life of fish-based products and prevent food waste.
Assuntos
Ácido Cítrico , Rahnella , Alimentos Marinhos , Animais , Ácido Cítrico/metabolismo , Alimentos Marinhos/microbiologia , Rahnella/genética , Rahnella/metabolismo , Salmão/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Ácido Acético/metabolismo , Ácido Acético/farmacologia , Microbiologia de Alimentos , Transcriptoma , Regulação Bacteriana da Expressão GênicaRESUMO
The choice of dialysate buffer in hemodialysis is crucial, with acetate being widely used despite complications. Citrate has emerged as an alternative because of its favorable effects, yet concerns persist about its impact on calcium and magnesium levels. This study investigates the influence of citrate dialysates (CDs) with and without additional magnesium supplementation on CKD-MBD biomarkers and assesses their ability to chelate divalent metals compared to acetate dialysates (ADs). A prospective crossover study was conducted in a single center, involving patients on thrice-weekly online hemodiafiltration (HDF). The following four dialysates were compared: two acetate-based and two citrate-based. Calcium, magnesium, iPTH, iron, selenium, cadmium, copper, zinc, BUN, albumin, creatinine, bicarbonate, and pH were monitored before and after each dialysis session. Seventy-two HDF sessions were performed on eighteen patients. The CDs showed stability in iPTH levels and reduced post-dialysis total calcium, with no significant increase in adverse events. Magnesium supplementation with CDs prevented hypomagnesemia. However, no significant differences among dialysates were observed in the chelation of other divalent metals. CDs, particularly with higher magnesium concentrations, offer promising benefits, including prevention of hypomagnesemia and stabilization of CKD-MBD parameters, suggesting citrate as a viable alternative to acetate. Further studies are warranted to elucidate long-term outcomes and optimize dialysate formulations. Until then, given our results, we recommend that when a CD is used, it should be used with a 0.75 mmol/L Mg concentration rather than a 0.5 mmol/L one.
Assuntos
Acetatos , Ácido Cítrico , Estudos Cross-Over , Hemodiafiltração , Magnésio , Humanos , Masculino , Feminino , Hemodiafiltração/métodos , Pessoa de Meia-Idade , Magnésio/administração & dosagem , Idoso , Estudos Prospectivos , Soluções para Diálise/química , CálcioRESUMO
Mortierella alpina is popular for lipid production, but the low carbon conversion rate and lipid yield are major obstacles for its economic performance. Here, external addition of organic acids involved in tricarboxylic acid cycle was used to tune carbon flux and improve lipid production. Citrate was determined to be the best organic acid that can be used for enhancing lipid production. By the addition of citrate, the lipid titer and content were approximately 1.24 and 1.34 times higher, respectively. Meanwhile, citrate supplement also promoted the accumulation of succinate, an important value-added platform chemical. Owing to the improved lipid and succinate production through adding citrate, the carbon conversion rate of M. alpina reached up to 52.17%, much higher than that of the control group (14.11%). The addition of citrate could redistribute carbon flux by regulating the expression level of genes related to tricarboxylic acid cycle metabolism. More carbon fluxes flow to lipid and succinate synthesis, which greatly improved the carbon conversion efficiency of M. alpina. This study provides an effective and straightforward strategy with potential economic benefits to improve carbon conversion efficiency in M. alpina.
Assuntos
Carbono , Ciclo do Ácido Cítrico , Ácido Cítrico , Mortierella , Ácido Succínico , Mortierella/metabolismo , Mortierella/genética , Ácido Succínico/metabolismo , Carbono/metabolismo , Ácido Cítrico/metabolismo , Lipídeos/biossíntese , Metabolismo dos Lipídeos , Regulação Fúngica da Expressão Gênica , FermentaçãoRESUMO
OBJECTIVE: This study compares two methods of citric acid-induced cough in guinea pigs in whole-body plethysmography (WBP) and double chamber plethysmography (DCP) to evaluate their efficacy. METHODS: Sixteen specific pathogen-free (SPF) and sixteen conventionally-bred (CON) animals were exposed to 0.4â¯M citric acid aerosol. They underwent cough provocation using both DCP and WBP methods. The number of coughs and latency to the first cough were recorded and analysed using statistical methods to determine significant differences between the two techniques. RESULTS: WBP resulted in significantly higher cough counts (WBP vs. DCP: 13±9 vs 2±3 for SPF; 14±8 vs 5±5 for CON; p<0.0001) and shorter latency (WBP vs. DCP: 59±6â¯s vs 159±14â¯s for SPF; 77±4â¯s vs 112±12â¯s for CON; p<0.0001) compared to DCP in both groups. CONCLUSION: Methodological differences substantially impact cough responses. WBP provides a more reliable and physiologically relevant methodology for cough assessment, suggesting the need for standardized protocols in cough research to enhance translational relevance.
Assuntos
Ácido Cítrico , Tosse , Modelos Animais de Doenças , Pletismografia Total , Animais , Tosse/fisiopatologia , Tosse/induzido quimicamente , Cobaias , Ácido Cítrico/farmacologia , MasculinoRESUMO
Three environmentally friendly organic acids, acetic acid, citric acid and oxalic acid, were used to treat citrus insoluble dietary fiber (CIDF) in present study, aiming to explore the changes in structural properties as well as their inhibitory effects on starch digestion. The results showed that organic acid treatment significantly reduced the particle size of all three CIDFs, with rougher and folded surfaces, improved crystallinity and thermal stability. During in vitro digestion, it was found that organic acid treatment could increase the particle size and viscosity of digestion, and also effectively enhance the inhibitory ability of α-glucosidase activity, resulting in a further blockage of starch digestion. The starch digestion in oxalic acid-treated group (with 3 wt% addition) was significantly reduced by 18.72 % compared to blank group and 9.05 % compared to untreated. These findings provide evidence of the potential of organic acid-treated insoluble dietary fiber as a functional food.
Assuntos
Citrus , Fibras na Dieta , Solubilidade , Amido , Citrus/química , Amido/química , Amido/metabolismo , Digestão/efeitos dos fármacos , Tamanho da Partícula , Ácido Cítrico/química , Viscosidade , alfa-Glucosidases/metabolismo , alfa-Glucosidases/química , Ácido Acético/química , Ácido Oxálico/químicaRESUMO
This article employs six organic acids to selectively dissolve Mo, Ni and V from spent catalysts, and the most effective acid is identified. Then, the effects of key leaching parameters, including acid concentration, temperature, and S/L ratio, on metal leaching are systematically explored to determine the leaching mechanism. The results demonstrate that the leaching ability of organic acids followed the order: oxalic acid > citric acid > tartaric acid > malonic acid > acetic acid > formic acid. The leaching process of metals was jointly influenced by acidolysis and complexolysis. Among them, more than 93.07 % of Mo, 86.64 % of V, and 74.21 % of Ni were selectively leached with oxalic acid at the optimum condition: S/l: 1/20, oxalic acid: 1.0 mol/L, temp: 60 °C. From the correlation coefficients, the resulting activation energies, and n values, it was demonstrated that Mo and V followed the Avrami dissolution reaction model, V leaching was controlled by the diffusion mode, and Mo leaching was controlled by a mixed mode of chemical reaction and diffusion. The dissolution behavior of both metals consistently adhered to the linear trend of the Avrami kinetic model under varying S/L ratios and oxalic acid concentrations.
Assuntos
Molibdênio , Níquel , Ácido Oxálico , Cinética , Níquel/química , Catálise , Ácido Oxálico/química , Molibdênio/química , Tartaratos/química , Ácido Cítrico/química , Formiatos/química , Ácido Acético/química , MalonatosRESUMO
Excessive heavy metal contaminants in soils have serious ecological and environmental impacts, and affect plant growth and crop yields. Phytoremediation is an environmentally friendly means of lowering heavy metal concentrations in soils. In this study, we analyzed phenotypic and physiological traits, and the transcriptome and metabolome, of sheepgrass (Leymus chinensis) exposed to cadmium (Cd), lead (Pb), or zinc (Zn). Phenotypic and physiological analysis indicated that sheepgrass had strong tolerance to Cd/Pb/Zn. Transcriptomic analysis revealed that phenylpropanoid biosynthesis and organic acid metabolism were enriched among differentially expressed genes, and metabolomic analysis indicated that the citrate cycle was enriched in response to Cd/Pb/Zn exposure. Genes encoding enzymes involved in the phenylpropanoid and citrate cycle pathways were up-regulated under the Cd/Pb/Zn treatments. Organic acids significantly reduced heavy metal accumulation and improved sheepgrass tolerance of heavy metals. The results suggest that synergistic interaction of the phenylpropanoid and citrate cycle pathways in sheepgrass roots induced organic acid secretion to alleviate heavy metal toxicity. A cascade of enzymes involved in the interacting pathways could be targeted in molecular design breeding to enhance phytoremediation.
Assuntos
Biodegradação Ambiental , Metais Pesados , Poluentes do Solo , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Cádmio/toxicidade , Cádmio/metabolismo , Poaceae/metabolismo , Poaceae/efeitos dos fármacos , Ciclo do Ácido Cítrico/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Zinco/metabolismo , Chumbo/toxicidade , Chumbo/metabolismo , Transcriptoma/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácido Cítrico/metabolismoRESUMO
Recognizing the pervasive presence of alumina minerals and low-molecular-weight organic acids (LMWOAs) in the environment, this study addressed the gap in the interaction mechanisms within the ternary system involving these two components and Fe(II). Specifically, the impacts of LMWOAs on hydroxyl radicals (â¢OH) production and iron species transformation during Fe(II) oxidation on γ-Al2O3 mineral surface were examined. Results demonstrated that adding 0.5 mM oxalate (OA) or citrate (CA) to the γ-Al2O3/Fe(II) system (28.1 µM) significantly enhanced â¢OH production by 1.9-fold (51.9 µM) and 1.3-fold (36.2 µM), respectively, whereas succinate (SA) exhibited limited effect (30.7 µM). Raising OA concentration to 5 mM further promoted â¢OH yield to 125.0 µM after 24 h. Deeper analysis revealed that CA facilitated the dissolution of adsorbed Fe(II) and its subsequent oxygenation by O2 through both one- and two-electron transfer mechanisms, whereas OA enhanced the adsorption of dissolved Fe(II) and more efficient two-electron transfer for H2O2 production. Additionally, LMWOAs presence favored the formation of iron minerals with poor crystallinity like ferrihydrite and lepidocrocite rather than well-crystallized forms such as goethite. The distinct impacts of various LMWOAs on Fe(II) oxidation and â¢OH generation underscore their unique roles in the redox processes at mineral surface, consequently modulating the environmental fate of prototypical pollutants like phenol.
Assuntos
Óxido de Alumínio , Radical Hidroxila , Oxirredução , Radical Hidroxila/química , Óxido de Alumínio/química , Minerais/química , Ferro/química , Adsorção , Ácido Cítrico/químicaRESUMO
Light exposure during manufacturing, storage, and administration can lead to the photodegradation of therapeutic proteins. This photodegradation can be promoted by pharmaceutical buffers or impurities. Our laboratory has previously demonstrated that citrate-Fe(III) complexes generate the â¢CO2- radical anion when photoirradiated under near UV (λ = 320-400 nm) and visible light (λ = 400-800 nm) [Subelzu, N.; Schöneich, C. Mol. Pharmaceutics 2020, 17 (11), 4163-4179; Zhang, Y. Mol. Pharmaceutics 2022, 19 (11), 4026-4042]. Here, we evaluated the impact of citrate-Fe(III) on the photostability and degradation mechanisms of disulfide-containing proteins (bovine serum albumin (BSA) and NISTmAb) under pharmaceutically relevant conditions. We monitored and localized competitive disulfide reduction and protein oxidation by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis depending on the reaction conditions. These competitive pathways were affected by multiple factors, including light dose, Fe(III) concentration, protein concentration, the presence of oxygen, and light intensity.
Assuntos
Anticorpos Monoclonais , Compostos Férricos , Luz , Oxirredução , Soroalbumina Bovina , Espectrometria de Massas em Tandem , Raios Ultravioleta , Soroalbumina Bovina/química , Espectrometria de Massas em Tandem/métodos , Animais , Anticorpos Monoclonais/química , Compostos Férricos/química , Cromatografia Líquida de Alta Pressão , Soluções Tampão , Fotólise , Bovinos , Ácido Cítrico/química , Dissulfetos/química , Ferro/químicaRESUMO
This study evaluated the effect of fluoride varnishes containing micrometric or nanosized sodium trimetaphosphate (TMP) on dentin erosive wear in vitro. Bovine root dentin blocks were selected by surface hardness and randomly divided into five experimental groups/varnishes (n = 20/group): placebo, 5% sodium fluoride (NaF); 5% NaF+5% micrometric TMP; 5% NaF+2.5% nanosized TMP; and 5% NaF+5% nanosized TMP. Half of the surface of all blocks received a single application of the assigned varnish, with subsequent immersion in artificial saliva for 6 h. Varnishes were then removed and the blocks were immersed in citric acid (90 s, 4×/day, 5 days). After each erosive cycle, ten blocks of each group were immersed in a placebo dentifrice for 15 s (ERO), while the other ten blocks were subjected to abrasion by brushing (ERO+ABR). Dentin erosive wear was assessed by profilometry. Data were submitted to 2-way ANOVA and to the Holm-Sidak test (p<0.05). Dentin erosive wear was significantly higher for ERO+ABR than for ERO for all varnishes. TMP-containing varnishes promoted superior effects against dentin erosive wear compared with 5% NaF alone; and 5% nanosized TMP led to the lowest wear among all varnishes. In conclusion, the addition of TMP to conventional fluoride varnish (i.e., varnish containing only NaF) enhanced its protective effects against bovine root dentin erosion and erosion+abrasion. Additionally, the use of 5% nanosized TMP led to superior effects in comparison to 5% micrometric TMP, both for erosion and erosion+abrasion in vitro.
Assuntos
Dentina , Fluoretos Tópicos , Teste de Materiais , Polifosfatos , Fluoreto de Sódio , Propriedades de Superfície , Erosão Dentária , Bovinos , Animais , Polifosfatos/farmacologia , Polifosfatos/química , Dentina/efeitos dos fármacos , Fluoreto de Sódio/farmacologia , Erosão Dentária/prevenção & controle , Fluoretos Tópicos/farmacologia , Análise de Variância , Fatores de Tempo , Propriedades de Superfície/efeitos dos fármacos , Distribuição Aleatória , Reprodutibilidade dos Testes , Nanopartículas/química , Abrasão Dentária/prevenção & controle , Saliva Artificial/química , Ácido Cítrico/farmacologia , Valores de Referência , Testes de DurezaRESUMO
BACKGROUND: Regional citrate anticoagulation (RCA) is recommended during continuous renal replacement therapy. Compared to systemic anticoagulation, RCA provides a longer filter lifespan with the risk of metabolic alkalosis and impaired calcium homeostasis. Surprisingly, most RCA protocols are designed for continuous veno-venous hemodialysis or hemodiafiltration. Effective protocols for continuous veno-venous hemofiltration (CVVH) are rare, although CVVH is a standard treatment for high-molecular-weight clearance. Therefore, we evaluated a new RCA protocol for postdilution CVVH. METHODS: This is a monocentric prospective interventional study to evaluate a new RCA protocol for postdilution CVVH. We recruited surgical patients with stage III acute kidney injury who needed renal replacement therapy. We recorded dialysis and RCA data and hemodynamic and laboratory parameters during treatment sessions of 72 h. The primary endpoint was filter patency at 72 h. The major safety parameters were metabolic alkalosis and severe hypocalcemia at any time. RESULTS: We included 38 patients who underwent 66 treatment sessions. The mean filter lifespan was 66 ± 12 h, and 44 of 66 (66%) filters were patent at 72 h. After censoring for non-CVVH-related cessation of treatment, 83% of all filters were patent at 72 h. The delivered dialysis dose was 28 ± 5 ml/kgBW/h. The serum levels of creatinine, urea and beta2-microglobulin decreased significantly from day 0 to day 3. Metabolic alkalosis occurred in one patient. An iCa++ below 1.0 mmol/L occurred in four patients. Citrate accumulation did not occur. CONCLUSIONS: We describe a safe, effective, and easy-to-use RCA protocol for postdilution CVVH. This protocol provides a long and sustained filter lifespan without serious adverse effects. The risk of metabolic alkalosis and hypocalcemia is low. Using this protocol, a recommended dialysis dose can be safely administered with effective clearance of low- and middle-molecular-weight molecules. TRIAL REGISTRATION: The study was approved by the medical ethics committee of Heinrich-Heine University Duesseldorf (No. 2018-82KFogU). The trial was registered in the local study register of the university (No: 2018044660) on 07/04/2018 and was retrospectively registered at ClinicalTrials.gov (ClinicalTrials.gov Identifier: NCT03969966) on 31/05/2019.
Assuntos
Injúria Renal Aguda , Anticoagulantes , Ácido Cítrico , Terapia de Substituição Renal Contínua , Hemofiltração , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Injúria Renal Aguda/terapia , Alcalose/etiologia , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Ácido Cítrico/administração & dosagem , Ácido Cítrico/uso terapêutico , Protocolos Clínicos , Hemofiltração/métodos , Hipocalcemia/etiologia , Estudos Prospectivos , Resultado do TratamentoRESUMO
Vitamin C is extensively used in cosmetic formulation, howbeit stability is the supreme demerit that limits its use in beautifying products. Numerous techniques are being employed to inhibit the degradation of vitamin C caused by formulation components to facilitate the use in skin rejuvenating products. Diverse materials are being exercised in formulation to stabilize the ascorbic acid and ingredients selected in this formulation composition help for stabilization. The initial stable prototype is developed and further optimization is accomplished by applying the design of experiment tools. The stable pharmaceutical formulations were evaluated for the evaluation parameters and designated as two optimized formulations. The analytical method for the assay of ascorbic acid from the United States pharmacopeia and the related substance method from European pharmacopeia has been modified to be used for cream formulation. The DoE design exhibited that the stability of formulation is impacted by citric acid and tartaric acid but not by propylene glycol and glycerin. The analysis results of topical formulations for the evaluation parameter exhibited satisfactory results. The in-vitro release study method has been developed, optimized, and validated to fit the analysis. The in-vitro studies have been performed for selected compositions and both the formulation has similar kinds of release patterns. The stability study as per ICH guidelines exhibited that the product is stable for accelerated, intermediate, and room-temperature storage conditions. The optimized formulation shows constant release and permeation of ascorbic acid through the skin. The formulation with the combinations of citric acid, tartaric acid, and tocopherol is more stable and the degradation of vitamin C has been reduced significantly. The beaucoup strategies in the unique composition help to protect the degradation by inhibiting the multitudinous degradation pathways.