Metaphosphoric Acid Research Articles

SNaP-C: Validation of a novel, selective silver nanoparticle antioxidant capacity assay for Vitamin C content in beverages

A validated silver nanoparticle assay (SNaP-C) for quantitation of Vitamin C, as ascorbic acid (AA) and total AA (TAA), was applied to 31 beverages. SNaP-C assay results (LOD of 2.2 mg/L AA) were compared to AA and TAA determined by high-performance liquid chromatography with UV/Vis (LOD = 0.4 mg/L AA), and two well-known assays. All approaches were calibrated using meta-phosphoric acid stabilized AA, where the reducing agent tris(2-carboxyethyl) phosphine hydrochloride was added to convert dehydroascorbic acid to AA for determination of TAA. Statistical comparisons of these four resulting datasets were completed. SNaP-C and HPLC were not statistically significantly different (P > 0.05) for comparison of AA and TAA (mg/L) in these samples, whereas the CUPRAC and Folin-Ciocalteu assays statistically significantly overestimated values of AA and TAA content, respectively. The SNaP-C method is a novel assay that has high specificity for AA capable of quantifying TAA with addition of TCEP.

Hexakis[p-(hydroxymethyl)phenoxy]cyclotriphosphazene as an Environmentally Friendly Modifier for Polyurethane Powder Coatings with Increased Thermal Stability and Corrosion Resistance.

Protection against fire and the corrosion of metals is necessary to ensure human safety. Most of the fire and corrosion inhibitors do not meet the ecological requirements. Therefore, effective and ecological methods of protecting metals are currently a challenge for researchers. In this work, the influence of hexakis(4-(hydroxymethyl)phenoxy)cyclotriphosphazene (HHPCP) on the characteristics of powder coatings was examined. The coatings' properties were investigated by measuring the roughness, hardness, adhesion to the steel surface, cupping, gloss, scratch resistance, and water contact angle. The thermal stability was studied by furnace test and TGA analysis. The corrosion resistance test was carried out in a 3.5% NaCl solution. The distribution of phosphazene-derived segments in the coating was examined by GD-EOS analysis. Modified coatings show better corrosion and thermal resistance and can be used for the protection of the steel surface. Their better corrosion resistance is due to the electroactive properties of the phosphazene ring and its higher concentration at the coating surface, confirmed by GD-EOS analysis. The increase in thermal resistance is due to the effect of the formation of phosphoric metaphosphoric and polyphosphoric acids during the decomposition of HHCPC, which remain in the condensed char phase and play a crucial role in surface protection.

Reduced Vitamin C Levels in Patients with Bleeding of Unknown Cause and Generalized Joint Hypermobility

Introduction Vitamin C is essential for the synthesis of collagen. Ehler-Danlos syndrome (EDS) is a group of collagen disorders associated with generalized joint hypermobility (HM), bleeding and bruising. The genetic cause of the HM EDS subtype (hEDS) is unknown. Referral to haematology clinics may result in the diagnosis: bleeding of unknown cause (BUC), where no specific haemostatic treatment is available. However, it is a clinical experience, published in many textbooks, that bleeding, and bruising associated with EDS improve by oral intake of vitamin C. No previous studies examined vitamin C levels in patients with BUC. The aim of the study is to investigate the association of vitamin C levels with HM and vascular fragility in patients with BUC. Methods Patients with bleeding tendency are referred to our Haemophilia Center. Following ISTH-BAT score, normal coagulation test (INR, APTT, fibrinogen, F8, F9, F11, F13, VWFAg, VWFRist) and inconclusive results of flow cytometry analysis of platelet function, patients are diagnosed with BUC. Patients with a high ISTH-BAT score > 10 were included in this study. We performed clinical examinations by a tourniquet test for capillary fragility and a Beighton score for generalized HM. A skin extensibility test was performed by pulling on the skin off the forearm and the lateral side of the throat until resistance was met. The test was considered positive (abnormal) if the skin extended more than 2 cm in both sites when pulled. Germline DNA was analyzed by whole genome sequencing (WGS) analysis and an in silico panel of 170 genes associated with bleeding and generalized HM was examined. Additionally, homozygous polymorphism in vitamin C genes ( GULOP, SLC23A1, SLC23A2, SVCT1, HP, GST and SOD2) known to cause reduced vitamin C levels, were assessed Vitamin C analysis: The participants received oral and written guidelines regarding intake of vitamin C in relation to the blood sample. The guidelines included no vitamin C supplements for 3 days before the blood sampling and no intake of vitamin C rich food on the day of the appointment. Plasma samples were immediately acidified by addition of 10% meta-phosphoric acid to ensure the stability of ascorbic acid, and subsequently analyzed by high-performance liquid chromatography. Severe vitamin C deficiency was defined as <11µM, deficiency as < 23 µM, suboptimal status as 23-49 µM and adequate status as >49 µM. Results Sixty probands and 20 healthy age- and gender-matched controls (HC) were included. Most patients were women (56/60, 93%), median age 48 (range 21- 75) and median BAT score 13 (range 10-21). By WGS a 67-year woman with Beighton score 7 was diagnosed with Noonan syndrome due to a pathogenic variant in PTPN11 (c.922A>G). Also, a 62-year woman without HM was diagnosed with mild FV deficiency due to a heterozygous variant in F5 (c.449A>G). No other causal variants were identified. In a patient with a homozygous variant in SLC23A1, vitamin C level was suboptimal 42µM.Suboptimal vitamin C levels were found in 19/60 patients and 2/20 HC. One patient was severely vitamin C deficient (7µM). Vitamin C levels were significantly lower in patients compared to HC (median 56 µM vs 76 µM; p = 0.012). Beighton score was positive in 29/60 patients and 1/20 HC (p<0.001). In 18/60 patients versus 0/20 HC the skin extensibility test was abnormal (p = 0.01). In 12/29 patients with a positive Beighton score the test for skin extensibility was also positive indicating a diagnosis of hEDS. Tourniquet test was positive (> 10 petechiae) in 18/60 patients and 4/20 HC (p>0.5). Patients with positive Beighton scores had significantly higher BAT scores than patients without HM (P= 0.014). No significant associations were found between vitamin C levels, a positive Beighton score, a positive Tourniquet test or a high BAT score respectively. Conclusions We found that a high proportion of patients with BUC have generalized HM, abnormal skin extensibility and positive tourniquet test. Indeed, patients with HM had increased ISTH-BAT scores compared to patients with negative Beighton scores. Our data support that hEDS may be an underlying cause of BUC. Further studies are needed to determine the genetic background of hEDS. Levels of vitamin C were reduced in patients with BUC compared to age and sex matched control. Our results could pave the way for a randomized study of vitamin C supplements versus placebo for bleeding and bruising in patients with generalized HM and BUC.

Phosphorylated cellulose nanocrystals: Optimizing production by decoupling hydrolysis and surface modification

Urea and phosphoric acid are essential for the isolation of phosphorylated cellulose nanocrystals (CNCs). Besides limiting dissolution of nanocrystals, urea facilitates the swelling of fibres thus increasing access for the phosphorylating agent. The aim of this study was to determine optimal conditions for isolation of highly charged phosphorylated CNCs. Using a design of experiments approach, seventeen experiments in which reaction time, urea, and acid concentrations were varied, were conducted. A two-step process was used, in which CNCs were first isolated by treatment in phosphoric acid, and then treated with metaphosphoric acid, and urea. It is shown that a design of experiments approach to the phosphorylation of CNCs allows a much lower ratio of urea to acid than has previously been reported. CNCs with high surface charge (~1800 mmol kg−1) are possible using this method. This information is instructive to phosphorylation of cellulose nanomaterials which have a variety of applications e.g., water purification and medical biomaterials.

370 Evaluation of Nutrient Digestibility By Calves Born from Early and Late Shedding Angus Dams

Abstract Researchers have investigated several factors that could alter fetal growth, including nutrient restriction (Valiente et al., 2021), hair shedding (Gray et al., 2011), and extreme hot and cold temperatures (Davidson et al., 2022). Hot temperatures and increased humidity percentages in the southeast United States caused researchers to investigate the hair coats of Angus cattle in the commercial production setting. An improvement in fiber digestibility and calf birth and weaning weights has been observed in Angus dams that shed 50% of the winter hair coat by May (Gray et al., 2011; Burnett et al., 2021). Our objective of this experiment was to investigate the nutrient digestibility of Angus calves born to cows that on average, shed early compared with calves from cows that shed later. Newly weaned, purebred Angus bull calves (early; n = 6, late; n = 6) were housed in metabolism crates for 10 d. Before the trial, calves had a 14-d adaption period to a 14% CP textured feed (CPC 14% Developer, CPC Commodities, Fountain Run, KY) and offered ad libitum Cynodon dactlyon hay and water. After 3 d crate acclimation period, urine, feces, orts, and hay samples were collected for 7 d. Concentrate was offered at 0.25% of average BW. Approximately 5% samples were taken of feces, and urine samples had 1 to 1.5% of 25% metaphosphoric acid added to prevent ammonia volatilization, and both collections were composited by animal. Orts were collected at 0600 h daily, dried, and composited by animal. Laboratory analysis included dry matter (DM), organic matter (OM), ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), Kjeldahl N (CP), and fat. Data were analyzed using the GLM procedure of SAS 9.4 in a completely randomized design with calf as the experimental unit. Significant (P ≤ 0.05) means were separated using Fischer’s protected LSD. The model for intake included average daily DM and OM (kg) and adjusted by body weight (BW%). For digestibility analysis, the model included: DM, OM, ash, NDF, ADF, hemi-cellulose (HC), CP, and fat. The N retention model included: N retained (g/d), N retained/consumed (%), and N retained/DM intake (%). There were no differences between early or late calves for DM intake (5.502 ± 0.2774 kg/d; 2.251 ± 0.1247 %BW), or OM intake (5.199 ± 0.2591 kg/d; 2.128 ± 0.1166 %BW). There were no differences in digestibility for either group for DM, OM, Ash, NDF, ADF, HC, CP, or fat (Table 1.). There were also no differences in N retention in either group of calves (3.686 ± 2.0242 g/d; 4.366 ± 2.3964 %; 0.064 ± 0.0355 %). Further research is needed in this area to adequately understand factors influencing nutrient digestibility in calves born from early and late shedding dams.

To etch or not to etch, Part III: On the hydrophobic-rich content and fatigue strength of universal adhesives after long-term ageing

ObjectivesTo examine whether dentin-etching extension and/or the hydrophobic-rich content of hybrid layers would affect fatigue strengths of a mild universal adhesive after long-term aging. MethodsTwin-bonded resin-dentin interfaces were produced by etching sound midcoronal dentin beams with 32 % ortho-phosphoric acid for 15 s (OPA15s), 3 s (OPA3s) or 10 % meta-phosphoric acid for 15 s (MPA15s). Samples were bonded with a mild universal adhesive with or without additional coating using a solvent-free bisGMA-based bonding resin. Self-etch application served as control. Composite buildups were made with a nanofilled composite. Bar-shaped twin-bonded interfaces (0.9 × 0.9 × 12 mm) were aged for two years in artificial saliva at 37 ℃ and tested under 4-point flexure at quasi-static (n = 16) and cyclic loads (n = 35) until failure. The stress-life fatigue behavior was evaluated using the staircase method at 4 Hz. Crack initiation and fracture patterns were evaluated by SEM. Cyclic-loaded data was analyzed by Kruskal-Wallis on Ranks (α = 0.05). ResultsSignificantly higher fatigue life distributions and higher endurance limits were observed for less aggressive etch-and-rinse protocols (OPA3s and MPA15s) after long-term ageing. Hydrophobic-rich coating produced 20–32 % higher endurance limits, prevented micrometer-sized porosities at bonded interfaces, reduced etching-associated variability and lowered crack formation.SignificanceLong-term hydrolysis produces detrimental effects on the fatigue strength of resin-dentin interfaces. The bond-promotion effect of less aggressive etch-and-rinse protocols and the creation of hybrid layers with higher hydrophobic-rich content are critical to extend the durability of mild universal adhesives. Therefore, current oversimplification trends in adhesive dentistry may limit resin-dentin bonding performance.

A nitrogen‐rich DOPO‐based phosphoramide for improving the fire resistance of polycarbonate with comparable mechanical property

AbstractA nitrogen‐rich DOPO‐based phosphoramide (DPAPZ) was synthesized using aminopyrazine and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) as raw materials, and blended with polycarbonate (PC) through melting method. The chemical structure of DPAPZ was validated by FTIR, 1H NMR and 31P NMR. The presence of DPAPZ endowed PC/DPAPZ composites with better fire safety and smoke suppression. With the incorporation of 6 wt% DPAPZ, PC/DPAPZ‐6 composite reached UL‐94 V‐0 rating and 30.2% of limiting oxygen index value. Simultaneously, the peak of heat release rate and total heat release of PC/DPAPZ‐6 were reduced by 44.8% and 47.0% as compared with the pure PC, respectively. The DPAPZ displayed bi‐phase flame retardant roles. In the gas phase, the decomposition of DPAPZ released phosphorus‐containing free radicals acting as the quencher of reactive H·/OH· and nonflammable NH3 diluting O2/combustible volatiles. In the condensed phase, the phosphorus‐containing components were dehydrated into metaphosphoric acid or polymetaphosphate covering the surface to protect the PC matrix from further combustion, and to promote the formation of a dense carbon layer to interrupt the transmission of O2 and volatiles between the combustion zone and the inner. The tensile strength of the composites displayed almost no change but the elongation at break decreased slightly with the addition of DPAPZ.

Influence of BN doped 2‐hydroxyethyl methacrylate phosphate coated expandable graphite on flame retardancy and thermal conductivity of styrene‐butadiene rubber composites

AbstractAs one of the three general rubbers, styrene‐butadiene rubber (SBR) is widely used in the manufacturing of tires and cables. However, due to its unsatisfactory performance of flame retardancy and thermal conductivity, its rang of application is limited. In order to improve SBR's flame retardancy and thermal conductivity, flame retardant and thermal conductive additive EG microcapsules (BN‐PPEG) were prepared by doping boron nitride (BN) with 2‐hydroxyethyl methacrylate phosphate (HEMAP) as shell. The results of Fourier transform infrared spectroscopy, x‐ray diffraction, scanning electron microscope energy and TG showed that BN‐PPEG was successfully prepared. The thermal conductivity of the SBR composite added with 15 phr BN‐PPEG was 58.0% higher than that of pure SBR, and its limiting oxygen index (LOI) value reached 26.6%, which was 38.5% higher than that of pure SBR. The peak heat release rate (pHRR) of the composites was 53.9% lower than that of pure SBR. The main reasons were that the physical barrier of BN and EG, the phosphorous free radicals captured active free radicals generated by the decomposition of HEMAP when heated, and the carbonization of SBR was promoted by generated phosphoric acid, metaphosphoric acid and other substances.

97 Can Fecal Volatile Fatty Acids be Used as an Indicator of Ruminal Volatile Fatty Acids?

Abstract For in vitro digestibility experiments addressing both horses and cattle, feces have long been thought to be an equivalent surrogate for ruminal or cecal inoculum that would eliminate the need for fistulated animals. However, this assumption requires similar microbial and chemical properties among inoculum sources. Validation of the relationship of fecal to ruminal metabolic properties would allow for more readily accessible information on fermentation across nutrition experiments. Thus, the purpose of this study was to compare ruminal and fecal VFA production from heifers fed four bermudagrass (Cynodon dactylon [L.] Pers.) cultivars. Ruminally-fistulated heifers (n = 4) were assigned randomly to one of four bermudagrass cultivars (Coastal [COS], Russell [RUS], Tifton 44 [T44], or Tifton 85 [T85]) for four 30-d in vivo periods (21-d adaptation and 9-d collection). On d 28, rumen fluid (RF) samples were collected at 13 timepoints (0, 0.25, 0.5, 0.75, 1, 2, 3, 4, 8, 12, 16, 20, 24 h) and rectal fecal samples were collected at 7 timepoints (0, 0.5, 1, 2, 4, 8, 12 h). Samples were acidified with meta-phosphoric acid, and 2-ethylbutyric acid was included as an internal standard. Samples were assayed for acetic (A), propionic (P), isobutyric (IB), butyric (B), isovaleric (IV), valeric (V), 4-methylvalteric (4MV), and caproic (C) acids by gas-liquid chromatography. Data were analyzed using SAS v. 9.4. Heifers receiving COS produced less (P < 0.05) RF concentrations of A (25.01 mM), P (5.21 mM), and total VFA (34.2 mM) than T85 (43.4, 8.9, and 58.0 mM, respectively), T44 (42.0, 9.0, and 57.3 mM, respectively), and RUS (39.8 8.9, and 55.3 mM, respectively), which were all similar. Ruminal B was greatest (P < 0.05) from RUS (5.4 mM) and least from COS (3.1 mmol/L), with T44 and T85 intermediate (4.9 and 4.4 mM, respectively). There was no effect of cultivar (P ≥ 0.10) on RF IB, IV, V, or 4MV concentrations. Fecal IB was correlated (P < 0.05) with RF IV (r = 0.59) and tended to be correlated (P ≤ 0.09) with RF A (r = 0.39), P (r = 0.39), C (r = 0.37), and total VFA (r = 0.38). Fecal P was correlated (P < 0.05) with RF IV (r = 0.51). No other fecal VFA were correlated with RF VFA. Results are interpreted to mean that COS results in decreased ruminal fermentation relative to the other cultivars tested. However, there is little indication that fecal VFA can serve as an indicator for ruminal fermentation.

A rapid GC-FID method for determination of endogenous glutathione in wheat flour

An improved gas chromatographic method using flame ionization detection (GC-FID) for quantification of free glutathione (GSH), free glutathione disulphide (GSSG), total free glutathione (TFG) and protein bound glutathione (PSSG) in wheat flour has been developed. The process involves extraction of GSH and GSSG, wherein the extraction efficiencies of five different solvent systems, including acetonitrile, methanol, trichloroacetic acid (TCA), meta-phosphoric acid (MPA) and perchloric acid (PCA) were tested. A comparison between 1,4-dithiothreitol (DTT) and tris(2-carboxyethyl)phosphine (TCEP) was made in order to evaluate their efficacy to reduce GSSG to GSH. Results showed that TCEP reduced GSSG to GSH, and released GSH from PSSG, whereas DTT did not reduce GSSG to GSH at a sufficient level at the tested experimental conditions. The method showed a linear response for the concentration in the range of 6.25–50 nmol/mL. The limit of detection and the limit of quantification values were 2.03 and 6.08 nmol/mL, respectively. The level of GSH in 40 different wheat flours was in the range of 19.3–137 nmol GSH/g, while GSSG and PSSG levels ranged from 4.32 to 200 and 5.15–61.4 nmol GSH equivalents/g flour. Pearson's correlation coefficients showed minor positive correlations for baking volume, protein and wet gluten to GSH.

Studies on the Phytochemistry, Medicinal Properties of Hippophae Rhamnoides

Because of its anti-inflammatory, antibacterial, and anti-cancer capabilities, Hippophaerhamnoides L. of the Elaeagnaceae family has been known as the "wonder plant." In addition, it shields the body against rheumatoid arthritis, psoriasis, multiple sclerosis, and other conditions that affect the throat, lungs, skin, and cardiovascular system. Seabuckthorn grows in five states in India: Himachal Pradesh, Sikkim, Jammu and Kashmir, Uttrakhand, and Arunachal Pradesh. Two of the four Hippophae species in these five states are in Jammu & Kashmir. Seabuckthorn is abundant in this state's Ladakh area, with populations flourishing in the districts of Leh and Kargil. Because the issue is so essential, the leaves of Hippophaerhamnoides are investigated to discover whether it contains any bioactive compounds. Generally, samples of shade-dried leaves from several Kargil populations are made using one of three distinct organic solvent: acetone, water, and methanol.In other cases, chloroform, meta-phosphoric acid, & petroleum ether were also detected. These were then analysed and subjected to various colour tests. According to the findings, these leaves contain many essential antioxidants and other health-promoting compounds. All three extract types tested positive for ascorbic acid, phenols, tannins, sterols, flavonoids,alkaloids, and saponins. All were devoid of anthocyanides, phlobatannins, steroids, and leucoanthocyanins. The aqueous extract contains terpenoids, flavonols, as well as cardiac glycosides. Their behavior in other solvents, however, is different. This article reviews the research on the medicinal properties of Sea buckthorn (Hippophaerhamnoides L.) for the treatment of both acute and chronic conditions.In many regions of the globe, the plant is eaten and utilised because of its nutritional and therapeutic benefits. Numerous in vitro, in vivo, and even some clinical research have investigated the therapeutic and pharmacological potential of sea buckthorn in the recent past. Several biochemical and pharmacological research has been conducted on sea buckthorn

Effect of the Viscosity and Application Time of Different Phosphoric Acids on the Bond Strength and Nanoleakage of Fiber Posts to Root Dentin.

To evaluate the effect of application time and viscosity of meta-phosphoric acid (MPA) and ortho-phosphoric acid (OPA) on the push-out resin-dentin bond strength (PBS) and nanoleakage (NL) at the adhesive-root dentin interface. Ninety-six roots of premolars were endodontically prepared and randomly assigned into groups according to the (i) acid (OPA and MPA), (ii) viscosity (gel and liquid), and (iii) application time (7 and 15 seconds). Fiber posts were cemented to the roots, which were then transversally sectioned into serial slices. The slices (cervical, medium, and apical) were subjected to PBS or NL. Analysis of the dentin etching pattern was performed using scanning electron microscopy (SEM). The PBS (MPa) and NL (%) data were subjected to three-way repeated-measures analysis of variance (ANOVA) and Tukey's test (α=0.05). The cross-product interaction was significant for both PBS and NL (p<0.001). No significant difference in the PBS was observed with the use of OPA compared to MPA (p>0.05). Higher PBS values were observed in the groups etched for 15 seconds compared to 7 seconds, regardless of the acid, viscosity, or root third (p<0.05). Lower NL was observed for MPA etching when compared to OPA etching (p<0.05), and these values were not affected by increasing the application time or acid viscosity (p>0.05). A more pronounced etching pattern was observed with OPA than MPA regardless of the acid viscosity. The use of 40% meta-phosphoric acid promoted adequate bond strength without increasing dentin demineralization or void spaces in the hybrid layer.

A guanidine phosphate-assisted boron nitride network enabled simultaneous improvements in flame resistance and thermal conductivity of polyvinyl alcohol (PVA)

Polyvinyl alcohol (PVA) plays an important role in many fields, but its flammability in air limits its wider application. In this work, SiO2@BN, a flame-retardant and heat conductive filler, were synthesized by hydrolysis of ethyl orthosilicate, and its structure and morphology were characterized successfully. SiO2@BN and guanidine phosphate (GP) were mixed evenly in the solution and added to PVA to form PVA composites. Based on the data of thermal conductivity, limiting oxygen index (LOI) and cone calorimeter test (CCT), the thermal conductivity and flame retardancy of the composite were studied, and the flame retardancy mechanism was explained. The results showed that the thermal conductivity of the PVA composite added with 2 wt.% SiO2@BN and 8 wt.% GP was 82.4% higher than that of pure PVA, and its LOI value reached 28.4%, which was 38.5% higher than that of pure PVA. The peak heat release rate (pHRR) and total heat release (THR) of the composites was 65.2% and 44.4% lower than those of pure PVA, respectively. The main reasons were the physical barrier effect of BN and SiO2, the dilution of the noncombustible gas generated by the decomposition of GP when heated, and the dehydration and carbonization of PVA promoted by the generated phosphoric acid, metaphosphoric acid and other substances.

Erythrocyte osmotic fragility is not linked to vitamin C nutriture in adults with well-controlled type 2 diabetes.

Erythrocyte fragility is amplified by oxidative stress and linked to diabetes-specific microvascular disease. Vitamin C supplementation improves glycemic indices in adults with type 2 diabetes (T2D) by improving antioxidant status. This cross-sectional study examined the relationships between vitamin C status and erythrocyte osmotic fragility in adults with or without T2D. Participants provided a fasting blood sample for erythrocyte osmotic fragility testing as a function of hypotonic NaCl concentrations. Additionally, plasma was stabilized with metaphosphoric acid prior to vitamin C analysis using isocratic reverse-phase UV-HPLC separation. Participants were grouped as diagnosed T2D (n = 14; 36% female; 55.5 ± 8.2 y; 31.5 ± 9.0 kg/m2; HbA1c: 7.4 ± 1.9%; plasma vitamin C: 36.0 ± 12.2 μM) or no diabetes (n = 16; 69% female; 38.7 ± 13.5 y; 26.8 ± 6.6 kg/m2; HbA1c: 5.4 ± 0.3%; plasma vitamin C: 34.8 ± 10.9 μM). Participant characteristics differed between groups only for age and hemoglobin A1c (HbA1c; p < 0.05). All hemolysis parameters were in normal ranges for the participants with T2D, and no significant differences in hemolysis parameters were noted between those with or without T2D. However, among participants with T2D, the NaCl concentration eliciting 50% hemolysis was higher for those with low (<7%) vs. high (>7%) HbA1c values (p = 0.037) indicating a slightly higher erythrocyte fragility in the former group. Vitamin C status did not impact any of the hemolysis parameters in adults with or without T2D. Thus, erythrocyte fragility was not elevated in T2D, and vitamin C nutriture was not related to erythrocyte fragility in adults with well-controlled T2D.

To etch or not to etch, Part II: On the hydrophobic-rich content and fatigue strength of universal adhesives

ObjectiveTo determine whether smear layer management, via conservative etching protocols, and the hydrophobic-rich content of hybrid layers would affect the fatigue strength of resin-dentin interfaces. MethodsBar-shaped dentin beams obtained from sound third molars were wet-polished for 30 s. Dentin was etched with 32 % ortho-phosphoric acid for 3 or 15 s, 10 % meta-phosphoric acid for 15 s or by a prime-and-rinse application using a mild universal adhesive (Scotchbond Universal, 3M ESPE). Self-etch application served as control. Coating was performed with a solvent-free bisGMA-based resin. Composite buildups were made with a nanofilled composite. Resin-dentin beams with twin-bonded interfaces were sectioned and stored in deionized water for 24 h at 37 ℃ before 4-point flexural quasi-static monotonic testing (n = 16). Stress-life fatigue behavior was evaluated under cyclic loading (n = 35) by the staircase method at 4 Hz. The tension side of cyclic-loaded unfractured beams were evaluated under SEM, along with the micro-morphology of etched dentin surfaces. Monotonic data was analyzed by two-way ANOVA followed by the Tukey Test and cyclic-loaded data by Kruskal-Wallis on Ranks (α = 0.05). ResultsEtching protocols and higher hydrophobic-rich content produced significantly higher fatigue life distributions (p < 0.05). Dentin demineralization was ranked as OPA 15 s > MPA 15 s > OPA 3 s > P + R > SE. Less aggressive etching and coating reduced crack formation at hybrid layers. SignificanceCurrent oversimplification trends in resin-dentin bonding constitute a trade-off between hybridization quality and easier adhesive handling. Controlled dentin etching and increasing the hydrophobic-rich content of hybrid layers may be necessary to extend the longevity of mild universal adhesives.

Relationships Between Erythrocyte Osmotic Fragility and Vitamin C Nutriture in Adults With or Without Type 2 Diabetes

ObjectivesErythrocyte osmotic fragility is noted in Gulo−/− knockout mice unable to synthesize vitamin C, likely due to the decreased production of cytoskeletal β-spectrin, which affects cell deformability. Individuals with type 2 diabetes (T2D) commonly display marginal vitamin C nutriture, a consequence of reduced cellular uptake and recycling of dehydroascorbic acid. This cross-sectional study examined the relationships between vitamin C status and erythrocyte osmotic fragility in adults with or without T2D.MethodsParticipants did not report unresolved disease conditions or supplementation with vitamin C for the previous three months. T2D diagnosis occurred ≥1 year before study enrollment. Participants provided a fasting venous blood sample for erythrocyte osmotic fragility testing based on erythrocyte lysis with varying concentrations of sodium chloride. In addition, plasma was extracted and mixed with equal volume of 10% (w/v) metaphosphoric acid in 2 mmol/L disodium EDTA and centrifuged at 4°C. The supernatant was stored at −80°C until analysis using isocratic reverse-phase UV-HPLC separation. All participants provided written informed consent and the study was approved by the local Institutional Review Board.ResultsParticipant characteristics did not differ significantly between groups with the exception of age (P < 0.01) and HbA1c (p = 0.002). Data are presented for adults with T2D (n = 14; 36% female; 55.5 ± 8.2 y; 31.5 ± 9.0 kg/m2; HbA1c: 7.4 ± 1.9%; plasma vitamin C: 36.0 ± 12.2 mM) and adults without T2D (n = 16; 69% female; 38.7 ± 13.5 y; 26.8 ± 6.6 kg/m2; A1c: 5.4 ± 0.3%; plasma vitamin C: 34.8 ± 10.9 mM). Compared to adults with T2D, erythrocyte osmotic fragility was significantly elevated in adults without T2D at 0.35% saline (+4.4%, p = 0.021). Vitamin C status did not impact erythrocyte osmotic fragility in adults with T2D; however, in adults without T2D, erythrocyte osmotic stability was linked to high vitamin C status at 0.35% saline (p = 0.054 unadjusted and p = 0.022 adjusted for age and gender).ConclusionsIn this small pilot trial, T2D was not related to increased erythrocyte osmotic fragility or marginal vitamin C status. However, vitamin C nutriture was directly linked to erythrocyte osmotic stability in adults without T2D.Funding SourcesThis research received no external funding.

Investigation of the mechanism of phytate-modified biochar-catalyzed persulfate degradation of Ponceau 2R

The mechanism of oxidation and degradation effect of phytate-modified biochar catalyzed persulfate on Ponceau 2R was investigated. Chemical-structural properties of phytate-modified biochar, such as surface morphology and surface oxygen-containing functional groups were characterized. The results suggest that modified biochar has better oxidation performance than unmodified biochar, and the modified biochar generated at 500 ℃ pyrolysis temperature can catalyze peroxymonosulfate (PMS) system with high efficiency, in large pH and temperature scope. And the degradation mechanism of Ponceau 2R by biochar-catalyzed PMS generation (BC-PMS) system was researched. It revealed that PBC300 (phytate-modified biochar pyrolyzed at 300 °C), PBC500 (phytate-modified biochar pyrolyzed at 500 °C), and PBC700 (phytate-modified biochar pyrolyzed at 700 °C) may have metaphosphoric acid linked to oxygen atoms and metaphosphoric acid linked in a bridging manner on the surface of biochar, catalyzing the production of hydroxyl radicals by PMS. PBC700 catalyzes the production of singlet oxygen by PMS through its structural defects, and singlet oxygen is the main catalytic product of PBC700.

PSIV-1 A comparison of chromatography methods to estimate ruminal VFA concentrations

Abstract The objective of this study was to describe two chromatography equipment and their methods (EM) and to evaluate their adequacy in estimating ruminal volatile fatty acid concentrations (VFA). Adequacy was assessed through precision and accuracy using three standard mixtures of known acetate, propionate, and butyrate concentrations. The standard mixtures were prepared for VFA analysis using high-performance liquid chromatography (HPLC) or gas chromatography (GC). Each mixture was injected ten times into each EM. The comparison was assessed with rumen fluid samples from four cannulated steers offered three diets at 2% BW. Diet A simulated a forage-based diet offered to cattle during the winter. Diet B simulated a grower-type diet offered to weaned calves. Diet C simulated a finisher-type diet offered to finishing cattle. Rumen fluid was collected three hours after the morning feeding for seven days for each diet and strained through 8 μm porosity fiberglass wool. Two 2-mL aliquots were stored at -20°C for HPLC analysis, while two 8-mL aliquots were diluted with 2 mL of 25% meta-phosphoric acid and stored at -20°C for GC analysis. Chromatograms without a flat baseline were removed from the analysis. For the adequacy evaluation, HPLC (R2 = 0.997; Cb = 0.874) was more precise and accurate at estimating total VFA than GC (R2 = 0.447; Cb = 0.763). When compared with the standards, HPLC estimated less (P &amp;lt; 0.001) total VFA (98.8 ± 10.3 mM) than GC (110.5 ± 17.4 mM). Concentrations for acetate, propionate, and butyrate in rumen fluid samples were estimated for each EM and analyzed using a random coefficients model. Similarly, estimates for acetate, propionate, and butyrate were less for HPLC than GC (P ≤ 0.002). VFA estimation differs depending on EM chosen. Further research should identify the source of difference in VFA estimation from each EM.

A highly sensitive, simple, and fast gas chromatography-mass spectrometry method for the quantification of serum short-chain fatty acids and their potential features in central obesity.

Short-chain fatty acids (SCFAs) are the main gut microbe metabolites, which have no more than six carbons. SCFAs are an emerging biomarker in metabolic diseases, including central obesity. Commonly, SCFAs are measured in fecal samples, where they are highly abundant, but here they do not reflect direct interactions with related organs. Serum SCFAs are assumed to be more associated with metabolic disease than fecal SCFAs, albeit at very low concentrations. The aim of the present study is to develop a highly sensitive, simple, and fast method for measuring six SCFAs in the serum by gas chromatography-mass spectrometry (GCMS). The serum is mixed with meta-phosphoric acid and 2,2-dimethylbutyric acid, followed by homogenization and centrifugation. Supernatant is then injected into the fused silica capillary column. The method is linear from 0.12-500μmol/L for all SCFAs with an accuracy of 90-117%. The total coefficient of variation for precision ranges from 3.8 to 14.1%. A preliminary study is performed with 32 centrally obese subjects and 17 lean subjects. The mean values of all SCFAs, including acetic, propionic, isobutyric, butyric, isovaleric, and valeric acid, in the centrally obese subjects are significantly higher compared with lean subjects. A significant correlation also exists between all SCFAs, with the waist circumference indicating that serum SCFAs have potential features with respect to metabolic diseases, especially central obesity. The validated GCMS method provides highly sensitive, fast, simple, and reliable SCFA quantitation in the serum and demonstrates the potential features of circulating SCFAs in central obesity.

Catalytic conversion of isopropyl alcohol on the heteropolic acid –titanium oxide system

A complex of modern physicochemical methods (X-ray phase analysis, low-temperature adsorption of nitrogen, scanning electron microscopy, element analysis)was used to studythe phase and texture properties of the phosphomolybdenum heteropoly acid–titanium oxide catalytic system. It was found that the optimal content of phosphomolybdenum heteropoly acid, which leads to an increase in the catalytic activity of titanium dioxide, is 7% wt.: the diisopropyl ether yield is higher,it reaches maximum values in a shorter period of time, and the samples are characterized by greater stability. It is shown that the textural characteristics of the specific surface area and dispersion are not the key factors responsible for the catalytic activity.It has been suggested that the activity of phosphomolybdenum heteropoly acid-containing samples is associated with the emergence of a new type of active centers that exhibit increased electron-donorproperties(terminal oxygen atoms of the outer frag-ments of octahedra М = О heteropolyacids). A drop in the catalytic activity of samples with a phosphomolyb-denum heteropoly acid content of more than 7% wt. associated with the formation of surface metaphosphoric acid and entails a decrease in active centers.