Effects of different types of Ringer's solution on patients with traumatic haemorrhagic shock: a prospective cohort study

OBJECTIVE

To compare the fluid resuscitation effect of sodium acetate Ringer's solution and sodium bicarbonate Ringer's solution on patients with traumatic haemorrhagic shock.

METHOD

We conducted a prospective cohort study in our emergency department on a total of 71 patients with traumatic haemorrhagic shock admitted between 1 December 2020 and 28 February 2022. Based on the time of admission, patients were randomly divided into a sodium bicarbonate Ringer's solution group and sodium acetate Ringer's solution group, and a limited rehydration resuscitation strategy was adopted in both groups. General data were collected separately, and the patients' vital signs (body temperature, respiration, blood pressure and mean arterial pressure (MAP)), blood gas indices (pH, calculated bicarbonate (cHCO3-), partial pressure of oxygen (PaO2), partial pressure of carbon dioxide (pCO2) and clearance of lactate (CLac)), shock indices, peripheral platelet counts, prothrombin times and plasma fibrinogen levels were measured and compared before and 1 h after resuscitation.

RESULTS

The post-resuscitation heart rate of the sodium bicarbonate Ringer's solution group was significantly lower than that of the sodium acetate Ringer's solution group (p < 0.05), and the MAP was also significantly lower (p < 0.05). The patients in the sodium bicarbonate Ringer's solution group had significantly higher pH, cHCO3- and PaO2 values and lower pCO2 and CLac values (p < 0.05) than those in the sodium acetate Ringer's solution group, and the post-resuscitation peripheral platelet counts and fibrinogen levels were significantly higher, with shorter plasma prothrombin times and smaller shock indices (p < 0.001).

CONCLUSION

Sodium bicarbonate Ringer's solution is beneficial for maintaining MAP at a low level after resuscitation. The use of sodium bicarbonate Ringer's solution in limited fluid resuscitation has positive results and is of high clinical value.

Physical and Chemical Compatibility of Medications Commonly Used in Critically Ill Patients With Balanced Crystalloids: A Systematic Review

OBJECTIVE

Evaluate available evidence of physical and/or chemical compatibility of commonly used medications in critically ill patients with balanced crystalloids.

DATA SOURCES

Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews were queried from inception to September 2022.

STUDY SELECTION AND DATA EXTRACTION

This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. English-language studies reporting physical and/or chemical compatibility data between 50 selected medications and balanced crystalloids were included. A previously designed tool to assess risk of bias was adapted for use.

DATA SYNTHESIS

Twenty-nine studies encompassing 39 (78%) medications and 188 unique combinations with balanced crystalloids were included. Combinations included 35 (70%) medications with lactated Ringer's, 26 (52%) medications with Plasma-Lyte, 10 (20%) medications with Normosol, and one (2%) medication with Isolyte. Studies commonly evaluated physical and chemical compatibility (55.2%). More medications were evaluated via Y-site than admixture. Incompatibilities were identified in 18% of combinations comprising 13 individual drugs.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This systematic review evaluates the compatibility of select critical care medications with balanced crystalloid solutions. Results may be used as a tool to guide clinicians on balanced crystalloid compatibility, potentially increasing ubiquitous use and reducing patient exposure to normal saline.

CONCLUSION AND RELEVANCE

Data are limited regarding chemical/physical compatibility of commonly used medications in critically ill patients with balanced crystalloids. Additional compatibility studies are warranted, particularly methodologically rigorous studies assessing Plasma-Lyte, Normosol, and Isolyte. Of the evaluated medications, there was a low frequency of incompatibilities with balanced crystalloids.

Carbon metabolism characteristics of quorum quenching bacteria Rhodococcus sp. BH4 determine the bioaugmentation efficiency under different carbon source conditions

Carbon sources are critical factors influencing bacterial bioaugmentation, however, the underlying mechanisms, particularly the metabolic characteristics of bioaugmented bacteria remain poorly understood. The bioaugmented bacterium Rhodococcus sp. BH4 secretes the quorum quenching (QQ) enzyme QsdA to disrupt the quorum sensing (QS) in the activated sludge (AS) process, reducing AS yield in-situ. This study investigated the carbon metabolic characteristics of BH4 and explored the effects on bioaugmentation with different influent carbon sources. Because of the absence of glucose-specific phosphoenol phosphotransferase system (PTS), BH4 prefers sodium acetate to glucose. However, the lactones produced during extracellular glucose metabolism enhance BH4 qsdA expression. Moreover, BH4 possess carbon catabolite repression (CCR), acetate inhibits glucose utilization. BH4 microbeads were added to reactors with different carbon sources (R1: sodium acetate; R2: glucose; R3: a mixture of sodium acetate and glucose) for in-situ AS yield reduction. During operation, AS reduction efficiency decreased in the following order: R1 > R3 > R2. R2 and R3 microbeads exhibited similar QQ activity to R1, with less BH4 biomass at 5 d. 13C labeling and Michaelis-Menten equation showed that, due to differences in the competitiveness of carbon sources, R1 BH4 obtained the most carbon, whereas R2 BH4 obtained the least carbon. Moreover, acetate inhibited glucose utilization of R3 BH4. Transcriptome analysis showed that R1 BH4 qsdA expression was the lowest, R2 BH4 was the most serious form of programmed cell death, and the R3 BH4 PTS pathway was inhibited. At 10 d, R1 BH4 biomass and microbead QQ activity were higher than that in R3, and the R2 BH4 lost viability and QQ activity. This study provides new insights into bioaugmentation from the perspectives of carbon source competitiveness, carbon metabolism pathways, and CCR.

Effect of sodium butyrate treatment at the basolateral membranes on the tight junction barrier function via a monocarboxylate transporter in goat mammary epithelial cells

In lactating mammary glands, tight junctions (TJs) prevent blood from mixing with milk and maintain epithelial cell polarity, which is important for milk production. This study aimed to investigate the effect of sodium acetate and sodium butyrate (SB) stimulation direction on the TJ barrier function, which is measured with regard to transepithelial electrical resistance and fluorescein flux, in goat mammary epithelial cells. The expression and localization of the TJ proteins claudin-3 and claudin-4 were examined using Western blotting and immunofluorescence. SB treatment in the lower chamber of cell culture inserts adversely affected the TJ barrier function, whereas sodium acetate barely had any effect, regardless of stimulation direction. In addition, SB treatment in the lower chamber significantly upregulated claudin-3 and claudin-4, whereas TJ proteins showed intermittent localization. Moreover, SB induced endoplasmic reticulum (ER) stress. ARC155858, a monocarboxylate transporter-1 inhibitor, alleviated the adverse impact of SB on TJs and the associated ER stress. Interestingly, sodium β-hydroxybutyrate, a butyrate metabolite, did not affect the TJ barrier function. Our findings indicate that sodium acetate and SB influence the TJ barrier function differently, and excessive cellular uptake of SB can disrupt TJs and induce ER stress.

Effect of 5% albumin on endothelial glycocalyx degradation during off-pump coronary artery bypass

PURPOSE

The integrity of the endothelial glycocalyx (EG), a critical player in vascular homeostasis, reportedly influences the outcomes of critically ill patients. We investigated the effect of 5% albumin, which preserved EG integrity in preclinical studies, vs balanced crystalloid solution on EG degradation in patients undergoing off-pump coronary surgery.

METHODS

Patients were randomized to receive either 5% albumin (N = 51) or balanced crystalloid solution (Plasma-Lyte [Baxter Incorporated, Seoul, Republic of Korea]; N = 53) for intravenous volume replacement during surgery (double-blinded). The primary outcome was plasma syndecan-1 concentration, a marker of EG degradation, measured after anesthetic induction (baseline), completion of grafting, and sternal closure. Secondary outcomes were atrial natriuretic peptide (ANP), tumour necrosis factor (TNF)-α, soluble thrombomodulin, and perioperative fluid balance.

RESULTS

The mean (standard deviation) fluid requirements were 833 (270) mL and 1,323 (492) mL in the albumin and Plasma-Lyte group, respectively (mean difference, -489 mL; 95% confidence interval [CI], -643 to -335; P < 0.001). Plasma syndecan-1 concentration increased after completion of grafting (median difference, 116 ng·mL-1; 95% CI, 67 to 184; P < 0.001) and sternal closure (median difference, 57 ng·mL-1; 95% CI, 36 to 80; P < 0.001) compared with those at baseline, without any intergroup differences. Atrial natriuretic peptide, TNF-α, and soluble thrombomodulin concentrations were similar between the two groups. The amount of chest tube drainage was greater in the albumin group than that in the Plasma-Lyte group (median difference, 190 mL; 95% CI, 18 to 276; P = 0.03).

CONCLUSION

Off-pump coronary surgery was associated with significant EG degradation. Yet, intraoperative fluid therapy with 5% albumin could not ameliorate EG degradation when compared with balanced crystalloid solution.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03699462); first posted 9 October 2018.

Short-chain fatty acids ameliorate experimental anti-glomerular basement membrane disease

BACKGROUND

Short-chain fatty acids (SCFAs), as the link between gut microbiota and the immune system, had been reported to be protective in many autoimmune diseases by the modulation of T cell differentiation. The pathogenic role of autoreactive Th1 and Th17 cells and the protective role of Treg cells in the pathogenesis of anti-GBM disease have been fully demonstrated. Thus, the present study aimed to investigate the therapeutic effects of SCFAs in a rat model of anti-GBM disease.

MATERIALS AND METHODS

Experimental anti-GBM disease was constructed by immunizing Wistar Kyoto rats with a nephrogenic T cell epitope α3127-148, and intervened by sodium acetate, sodium propionate, or sodium butyrate, 150 mM in the drinking water from day 0 to 42. Kidney injury was accessed by the biochemical analyzer, immunofluorescence, and immunohistochemistry. Antibody response was detected by ELISA. T cell clustering and proliferation were detected by flow cytometry. Human kidney 2 (HK2) cells were stimulated in vitro and cytokines were assessed by quantitative real-time PCR.

RESULTS

Treatment with sodium acetate, sodium propionate, or sodium butyrate ameliorated the severity of kidney impairment in rats with anti-GBM glomerulonephritis. In the sodium butyrate-treated rats, the urinary protein, serum creatinine, and blood urea nitrogen levels were significantly lower; the percentage of crescent formation in glomeruli was significantly reduced; and the kidneys showed reduced IgG deposition, complement activation, T cell, and macrophage infiltration as well as the level of circulating antibodies against anti-α3(IV)NC1. The treatment of sodium butyrate reduced the α3127-148-specific T cell activation and increased the Treg cells differentiation and the intestinal beneficial bacteria flora. It also alleviated the damage of HK2 cells treated with inflammatory factors and complement.

CONCLUSION

Treatment with SCFAs, especially butyrate, alleviated anti-GBM nephritis in rat model, indicating its potential therapeutic effects in clinical usage.

A pragmatic, open-label, randomized controlled trial of Plasma-Lyte-148 versus standard intravenous fluids in children receiving kidney transplants (PLUTO)

Acute electrolyte and acid-base imbalance is experienced by many children following kidney transplant. This is partly because doctors give very large volumes of artificial fluids to keep the new kidney working. When severe, fluid imbalance can lead to seizures, cerebral edema and death. In this pragmatic, open-label, randomized controlled trial, we randomly assigned (1:1) pediatric kidney transplant recipients to Plasma-Lyte-148 or standard of care perioperative intravenous fluids (predominantly 0.45% sodium chloride and 0.9% sodium chloride solutions). We then compared clinically significant electrolyte and acid-base abnormalities in the first 72 hours post-transplant. The primary outcome, acute hyponatremia, was experienced by 53% of 68 participants in the Plasma-Lyte-148 group and 58% of 69 participants in the standard fluids group (odds ratio 0·77 (0·34 - 1·75)). Five of 16 secondary outcomes differed with Plasma-Lyte-148: hypernatremia was significantly more frequent (odds ratio 3·5 (1·1 - 10·8)), significantly fewer changes to fluid prescriptions were made (rate ratio 0·52 (0·40-0·67)), and significantly fewer participants experienced hyperchloremia (odds ratio 0·17 (0·07 - 0·40)), acidosis (odds ratio 0·09 (0·04 - 0·22)) and hypomagnesemia (odds ratio 0·21 (0·08 - 0·50)). No other secondary outcomes differed between groups. Serious adverse events were reported in 9% of participants randomized to Plasma-Lyte-148 and 7% of participants randomized to standard fluids. Thus, perioperative Plasma-Lyte-148 did not change the proportion of children who experienced acute hyponatremia compared to standard fluids. However fewer fluid prescription changes were made with Plasma-Lyte-148, while hyperchloremia and acidosis were less common.

Modulation of antioxidant defense and PSII components by exogenously applied acetate mitigates salinity stress in Avena sativa

Salinity stress has detrimental effects on various aspects of plant development. However, our understanding of strategies to mitigate these effects in crop plants remains limited. Recent research has shed light on the potential of sodium acetate as a mitigating component against salinity stress in several plant species. Here, we show the role of acetate sodium in counteracting the adverse effects on oat (Avena sativa) plants subjected to NaCl-induced salinity stress, including its impact on plant morphology, photosynthetic parameters, and gene expression related to photosynthesis and antioxidant capacity, ultimately leading to osmoprotection. The five-week experiment involved subjecting oat plants to four different conditions: water, salt (NaCl), sodium acetate, and a combination of salt and sodium acetate. The presence of NaCl significantly inhibited plant growth and root elongation, disrupted chlorophylls and carotenoids content, impaired chlorophyll fluorescence, and down-regulated genes associated with the plant antioxidant defense system. Furthermore, our findings reveal that when stressed plants were treated with sodium acetate, it partially reversed these adverse effects across all analyzed parameters. This reversal was particularly evident in the increased content of proline, thereby ensuring osmoprotection for oat plants, even under stressful conditions. These results provide compelling evidence regarding the positive impact of sodium acetate on various plant development parameters, with a particular focus on the enhancement of photosynthetic activity.

Alleviation of adipose-hepatic glycolipid dysregulation by acetate in experimental PCOS model is associated with NF-κB/NLRP3 repression

This study hypothesized that acetate breaks the vicious cycle driving adipose-hepatic metabolic dysregulation in a rat model of polycystic ovarian syndrome (PCOS), possibly by suppression of nuclear factor-kappaB (NF-κB)/NOD-like receptor protein 3 (NLRP3) inflammasome. Female Wistar rats (8-week-old) were randomly allocated into four groups of n =6/group, which received vehicle, sodium acetate (200 mg), letrozole (1 mg/kg), and letrozole plus sodium acetate, respectively. The animals were treated by oral gavage, once daily for a period of 21 days. The PCOS animals were insulin-resistant, hyperandrogenic, and hypoestrogenic with decreased sex-hormone binding globulin. In addition, the hepatic tissue had increased lipid profile and decreased glycogen synthesis, while the adipose tissue showed decreased lipid profile with elevated glycogen synthesis. Besides, the results also showed increased malondialdehyde, γ-glutamyl transferase, lactate dehydrogenase, and inflammatory mediators with corresponding decrease in antioxidant defense in the hepatic and adipose tissues. Immunohistochemical evaluation also demonstrated severe expression with Bcl2-associated X protein/NLRP3 antibodies. Nonetheless, concomitant acetate supplementation attenuated these derangements. The present data collectively suggest that acetate ameliorates adipose-hepatic glycolipid dysregulation in experimental PCOS model by attenuating androgen excess and NF-κB/NLRP3 immunoreactivity.

Enhanced biological wastewater treatment supplemented with anaerobic fermentation liquid of primary sludge

The wastewater treatment performance in an inverted A2/O reactor supplemented with fermentation liquid of primary sludge was explored comparing to commercial carbon sources sodium acetate and glucose. Similar COD removal rate was observed with the effluent COD stably reaching the discharge standard for those 3 carbon sources. However, the fermentation liquid distributed more carbon source in the anaerobic zone. Fermentation liquid and sodium acetate tests achieved better nitrogen removal rate than glucose test. The fermentation liquid test showed the best biological phosphorus removal performance with the effluent phosphorus barely reaching the discharge standard. The microbial community characterization revealed that the fermentation liquid test was dominated by phylum Proteobacter in all the anoxic, anaerobic and aerobic zones. Denitrifying phosphorus accumulating organisms (PAOs) (i.e., genera Dechloromonas and unclassified_f__Rhodocyclaceae) were selectively enriched with high abundances (over 20%), which resulted in improved phosphorus removal efficiency. Moreover, the predicted abundances of enzymes involved in nitrogen and phosphorus removal were also enhanced by the fermentation liquid.

Effect of bio-chemical changes due to conventional ageing or chemical soaking on the texture changes of common beans during cooking

To establish the HTC defect development, the cooking kinetics of seeds of ten bean accessions (belonging to seven common bean market classes), fresh and conventionally aged (35 °C, 83% RH, 3 months) were compared to those obtained after soaking in specific salt solutions (in 0.1 M sodium acetate buffer at pH 4.4, 41 °C for 12 h, or 0.01 M CaCl2 at pH 6.2, 25 °C for 16 h and subsequently cooking in CaCl2 solution, or deionised water). The extent of phytate (inositol hexaphosphate, IP6) hydrolysis was evaluated to better understand the role of endogenous Ca2+ in the changes of the bean cooking kinetics. A significant decrease in the IP6 content was observed after conventional ageing and after soaking in a sodium acetate solution suggesting phytate hydrolysis (release of endogenous Ca2+). These changes were accompanied by an increase in the cooking time of the beans. Smaller changes in cooking times after soaking in a sodium acetate solution (compared to conventionally aged beans) was attributed to a lower ionisation level of the COOH groups in pectin (pH 4.4, being close to pKa value of pectin) limiting pectin Ca2+ cross-linking. In beans soaked in a CaCl2 solution, the uptake of exogenous cations increased the cooking times (with no IP6 hydrolysis). The change in cooking time of conventionally aged beans was strongly correlated with the extent of IP6 hydrolysis, although two groups of beans with low or high IP6 hydrolysis were distinguished. Comparable trends were observed when soaking in CaCl2 solution (r = 0.67, p = 0.14 or r = 0.97, p = 0.03 for two groups of beans with softer or harder texture during cooking). Therefore a test based on the Ca2+ sensitivity of the cooking times, implemented through a Ca2+ soaking experiment followed by cooking can be used as an accelerated test to predict susceptibility to HTC defect development during conventional ageing. On the other hand, a sodium acetate soaking experiment can be used to predict IP6 hydrolysis of conventionally aged bean accessions and changes of cooking times for these bean accessions (with exception of yellow bean-KATB1).

Delignified wheat straw for production of xylo-oligosaccharides and monosaccharides using acetic acid/sodium acetate solution

The production of xylo-oligosaccharides (XOS) from lignocelluloses with conjugated acid-base system is highly efficient. However, XOS production from wheat straw with conjugated system of acetic acid/sodium acetate (HAc/NaAc) has not been reported. In addition, the impact of delignification of wheat straw for XOS production was not clear. In this study, the optimal conditions for HAc/NaAc hydrolysis were: 0.4 M, molar ratio 10:1, 170 °C, and 60 min. The yield of XOS could be rose to 50.2% after the HAc/NaAc hydrolysate was hydrolyzed using xylanase. After 70.3% of lignin in wheat straw was removed by hydrogen peroxide-acetic acid treatment, the XOS yield of delignified wheat straw using HAc/NaAc reached 54.7%. Finally, a glucose yield of 96.6% was gained by cellulase from wheat straw solid. This work suggested that HAc/NaAc hydrolysis could efficiently produce XOS from wheat straw and the delignification of wheat straw was conducive to XOS and monosaccharides production.

Heterogeneous uptake of NO2 by sodium acetate droplets and secondary nitrite aerosol formation

The high NO₃^- concentration in fine particulate matters (PM_2.5) during heavy haze events has attracted much attention, but the formation mechanism of nitrates remains largely uncertain, especially concerning heterogeneous uptake of NO_X by aqueous phase. In this work, the heterogeneous uptake of NO₂ by sodium acetate (NaAc) droplets with different NO₂ concentrations and relative humidity (RH) conditions is investigated by microscopic Fourier transform infrared spectrometer (micro-FTIR). The IR feature changes of aqueous droplets indicate the acetate depletion and nitrite formation in humid environment. This implies that acetate droplets can provide the alkaline aqueous circumstances caused by acetate hydrolysis and acetic acid (HAc) volatilization for nitrite formation during the NO₂ heterogeneous uptake. Meanwhile, the nitrite formation will exhibit a pH neutralizing effect on acetate hydrolysis, further facilitating HAc volatilization and acetate depletion. The heterogeneous uptake coefficient increases from 5.2 × 10^-6 to 1.27 × 10^-5 as RH decreases from 90% to 60% due to the enhanced HAc volatilization. Furthermore, no obvious change in uptake coefficient with different NO₂ concentrations is observed. This work may provide a new pathway for atmospheric nitrogen cycling and secondary nitrite aerosol formation.

Robustness and stability of acetate-driven partial denitrification (PD) in response to high COD/NO3--N

Partial Denitrification (PD) producing nitrite for anammox may face the issue of relatively high chemical oxygen demand (COD) loading (i.e., COD/NO₃^--N) due to real wastewater being changed in substrate concentration and flowrate. In this study, three PD systems (R1, R2, R3) with sodium acetate providing electrons were developed to investigate the influence of the relatively high COD/NO₃^--N ratios (4.0, 6.0, and 8.0) on NO₂^--N production and the subsequent recoverability. It was found that a relatively high NO₂^--N production with nitrate-to-nitrite transformation ratio (NTR) of 74.0% could be still obtained despite COD/NO₃^--N even improving to 8.0 under limited reaction time (10 min) with small nitrate remaining. However, a deteriorated nitrite production was observed with sufficient reaction time (15 min) with NTR being lowered to 19.2%. Delightedly, when reducing influent COD/NO₃^--N to a normal level of 3.0, PD with high nitrite production was rapidly achieved after suffering from a relatively high COD/NO₃^--N (4.0-8.0) for 130 cycles. Besides, it was found the relatively high COD/NO₃^--N had a minor influence on the recoverability of PD, as evidenced by the close NTRs. Microbial analysis revealed the relative abundance of PD functional bacteria, Thauera, decreased under high COD/NO₃^--N, while it is still highly dominated in the systems, varying from 75.1% in R1 to 62.8% in R3 after around 110-cycles recovery. Furthermore, it appeared that the high pH (9.1-9.2) induced by sodium acetate also likely played a role in maintaining the excellent PD. Overall, this study demonstrated the robustness and stability of acetate-driven PD in response to high COD/NO₃^--N, further informing the technological superiority of PD in supplying stable and efficient nitrite, which provided solid technical support to apply it with anammox for high-efficient N removal.

The effects of acetate and glucose on carbon fixation and carbon utilization in mixotrophy of Haematococcus pluvialis

The culture method using sodium acetate and glucose, widely used as organic carbon sources in the mixotrophy of Haematococcus pluvialis, was compared with its autotrophy. In the 12-day culture, mixotrophy using sodium acetate and glucose increased by 40.4% and 77.1%, respectively, compared to autotrophy, but the mechanisms for the increasing biomass were different. The analysis of the mechanism was divided into autotrophic and heterotrophic metabolism. The mixotrophy with glucose increased the biomass by directly supplying the substrate and ATP to the TCA cycle while inhibiting photosynthesis. Gene expressions related to glycolysis and carbon fixation pathway were confirmed in autotrophy and mixotrophy with glucose and acetate. The metabolism predicted in the mixotrophy with acetate and glucose was proposed via autotrophic and heterotrophic metabolism analysis. The mechanism of Haematococcus pluvialis under mixotrophic conditions with high CO₂ concentration was confirmed through this study.

Acetate: A therapeutic candidate against renal disorder in a rat model of polycystic ovarian syndrome

Various endocrinometabolic diseases, inclusively polycystic ovarian syndrome (PCOS) has been linked with increased risk of renal dysfunction with attendant cardiovascular disease (CVD) in women of reproductive age. Short chain fatty acids (SCFAs) especially acetate have been suggested as an immunometabolic modulator. However, the impact of SCFAs, particularly acetate on renal disorder in PCOS individuals is unknown. The present study therefore hypothesized that acetate would circumvent renal dysfunction in a rat model of PCOS, probably by suppressing NF-κB-dependent mechanism. Eight-week-old female Wistar rats were randomly distributed into four groups (n = 6), which received vehicle, sodium acetate (200 mg/kg), letrozole (1 mg/kg) and letrozole plus sodium acetate, respectively. The administrations were done by oral gavage once daily for a duration of 21 days. Animals with PCOS showed insulin resistance, lipid dysmetabolism, hyperandrogenism, hyperleptinemia and hypoadiponectinemia. Besides, the result also revealed increased renal malondialdehyde, lactate production, inflammatory mediators (NF-κB and TNF-α), urea and creatinine concentration. Immunohistochemical evaluation of renal tissue also demonstrated severe expression of apoptosis and inflammation with BAX/NLRP3 antibodies. However, supplementation with acetate significantly attenuated these anomalies. Collectively, the present results suggest that acetate abolishes renal dysfunction in experimentally induced PCOS animals by attenuating androgen excess, apoptosis, oxidative stress and NF-κB/NLRP3 immunoreactivity.

The organics-mediated microbial dynamics and mixotrophic metabolisms in anammox consortia under micro-aerobic conditions

The engineering applications of mainstream anaerobic ammonium oxidation (anammox) have raised increasing attention due to its energy-efficient, however, the organics-mediated microbial dynamics and mixotrophic metabolisms in anammox consortia under micro-aerobic conditions are still elusive. Here, the response of the anammox process to sodium acetate and glucose at a C/N ratio ranging from 0 to 0.5 was investigated under micro-aerobic conditions, respectively. Results showed that the additional glucose could promote the nitrogen removal efficiency (NRE) and nitrogen removal rate (NRR) of anammox processes at a low C/N ratio (0.3), representing 84.00% and 0.53 N kg·m^-3·d^-1. The introduced organics could regulate the diversity of the microbial community and simplify the microbial relationship in anammox consortia. Anammox could not benefit from the introduced sodium acetate, while glucose could effectively enhance the anammox activity and microbial interactions in anammox consortia. Glucose might also stimulate the mixotrophic mechanism of Ca. Kuenenia, further promotes the proliferation of anammox sludge under micro-aerobic conditions. This study reveals that glucose could positively mediate microbial interactions and mixotrophic metabolism in anammox consortia under micro-aerobic conditions, which raises a new horizon for the proliferation of anammox sludge for mainstream engineering applications.

Enhancement of nutrients removal and biomass accumulation of algal-bacterial symbiosis system by optimizing the concentration and type of carbon source in the treatment of swine digestion effluent

The algae-bacteria symbiosis system (ABS) is used to effectively solve the problems of low carbon/nitrogen (C/N) ratio, low biodegradability and high ammonia toxicity in swine digestion effluent. This study examined the effects of the concentration and type of carbon source on ABS in the pollutants removal especially ammonia. When C/N ratio was 30:1 and carbon source was sodium acetate, the ABS was most conducive to the removal of nitrogen, phosphorus and COD, and to the accumulation of biomass and lipids. To make the wastewater discharge meet the relevant standard, the ABS + mono-cultivation of algae reprocessing system (MAS), was applied to actual swine digestion effluent. Through adjusting the C/N ratio in ABS to 30:1, the biomass concentration was 2.06 times higher than that of raw wastewater, and the removal efficiencies of NH₄⁺-N, TN, TP and COD increased by 1.43, 1.46, 1.95 and 1.28 times, respectively. The final concentrations of NH₄⁺-N, TN, TP and COD after the treatment of ABS (C/N ratio of 30:1) + MAS, were 16.98 ± 1.07 mg L^-1, 18.72 ± 1.81 mg L^-1, 0.48 ± 0.01 mg L^-1 and 263.49 ± 11.89 mg L^-1, respectively, reached the Chinese discharge standards for livestock and poultry wastewater. Bacterial community analysis showed that the dominant species of the ABS (C/N ratio of 30:1) was Corynebacterium (genus level). This study revealed that adjusting the concentration and type of carbon source was helpful to the nutrient cycling and resource utilization of ABS, indicating a feasible technique for treating high ammonia nitrogen digestate.

Low-temperature aerobic carbonization and activation of cellulosic materials for Pb2+ removal in water source

Targeting the removal of Pb²⁺ in wastewater, cellulosic materials were carbonized in an aerobic environment and activated via ion exchange. The maximum adsorption capacity reached 243.5 mg/g on an MCC-derived adsorbent activated with sodium acetate. The modified porous properties improved the adsorption capacity. The capacity could be completely recovered five times through elution with EDTA. Because of the negative effects of Ni, Mg, and Ca elements, the adsorption capacities of activated carbonized natural materials were lower than that of pure cellulose. N₂ adsorption measurement showed that the adsorbent had a large specific surface area as well as abundant micropores and 4-nm-sized mesopores. FTIR and surface potential results proved that carboxyl group was generated in the aerobic carbonization, and was deprotonated during ion exchange. This adsorbent consisted of C-C bonds as the building blocks and hydrophilic groups on the surface. XPS results demonstrated that the Pb 4f binding energies were reduced by 0.7-0.8 eV due to the interaction between Pb²⁺ and the activated adsorbent, indicating that the carboxylate groups bonded with Pb²⁺ through coordination interactions. Pseudo-second-order and Elovich kinetic models were well fitted with the adsorption processes on the pristine and activated carbonized adsorbents, indicative of chemisorption on heterogeneous surfaces. The Freundlich expression agreed well with the data measured, and the pristine and activated adsorbents had weak and strong affinities for Pb²⁺, respectively. The Pb²⁺ adsorption process was exothermic and spontaneous, and heat release determined the spontaneity. The adsorption capacity is attributed to the carboxylate groups and pores generated in the aerobic oxidation and ion exchange procedures.

Construction and carbon source optimization of a microbial-plant coupled reactor for treating acid mine drainage

Acid mine drainage (AMD) is recognized as one of the most serious contamination sources in the nonferrous metal mining industry. In this study, aerobic strains VCZ02 and VCZ09, which were identified as Leclercia adecarboxylata and Klebsiella aerogenes, were screened from 11 strains of copper-zinc-resistant bacteria in the soil of the Dexing copper mine with Cu²⁺/Zn²⁺ removal rates of 46.32%/41.03% and 57.96%/67.05%, respectively. The composition of extracellular polymers plays an important role in the removal of heavy metals by these two strains. A mixed community consisting of VCZ02 and VCZ09 was coupled with Sagittaria trifolia L.var.sinensis (Sims) Mak to construct a microbial-plant coupled reactor to remediate AMD. Under the optimal condition of sodium acetate as carbon source, the pH of AMD increased from less than 5 to above 6.5, showing Cu²⁺/Zn²⁺ removal rates of 70-80% and above 30%, respectively. SEM-EDS results showed that VZC02 and VZC09 in the coupled reactor also helped with resisting the toxicity of heavy metals to plants by forming biofilms on the root surface and increasing the content of heavy metals on the surface of roots, thus improving the treatment effect of plants. This study provides a theoretical basis for the bioremediation of AMD and its application.

Promotion of nitrogen removal in a zero-valent iron-mediated nitrogen removal system operated in co-substrate mode

In this study, the performance and mechanism of nitrogen removal were investigated in a zero-valent iron-mediated nitrogen removal system operated in co-substrate mode with sodium acetate as the organic carbon source. The results showed that the additional organic matter had the capacity to promote NH4+-N and total inorganic nitrogen (TIN) removal with efficiencies of 91.09% and 84.10%, and increases of 60.06% and 75.32% compared with the control group, respectively. The organic matter also stimulated the production of extracellular polymer substances that reduced the passivation and toxicity of iron to microorganisms. The ammonia oxidation activity was 2.5 times higher than that in the control group, and the anammonia oxidation activity and denitrification activity were substantially higher than in the control group with TIN removal efficiencies of 1.02 and 1.19 mgN/(gVSS·d), respectively. In addition, the organic matter increased the enrichment of the heterotrophic denitrification bacterium Diaphorobacter and facultative iron salt-based bacterium Dechloromonas.

Dissolved organic nitrogen derived from wastewater denitrification: Composition and nitrogenous disinfection byproduct formation

Microbially derived dissolved organic nitrogen (mDON) is a major fraction of effluent total nitrogen at wastewater treatment plants with enhanced nutrient removal, which stimulates phytoplankton blooms and formation of toxic nitrogenous disinfection by-products (N-DBPs). This study identified denitrifiers as major contributors to mDON synthesis, and further revealed the molecular composition, influential factors and synthetic microorganisms of denitrification-derived mDON compounds leading to N-DBP formation. The maximum mDON accumulated during denitrification was 8.92% of converted inorganic nitrogen, higher than that of anammox (4.24%) and nitrification (2.76%). Sodium acetate addition at relatively high C/N ratio (5-7) favored mDON formation, compared with methanol and low C/N (1-3). Different from acetate, methanol-facilitated denitrification produced 13-69% more lignin-like compounds than proteins using Orbitrap LC-MS. The most abundant N-DBPs formed from denitrification-derived mDON were N-nitrosodibutylamine and dichloroacetonitrile (13.32 μg/mg mDON and 12.21 μg/mg mDON, respectively). Major amino acids, aspartate, glycine, and alanine were positively correlated with typical N-DBPs. Biosynthesis and degradation pathways of these N-DBP precursors were enriched in denitrifiers belonging to Rhodocyclaceae, Mycobacteriaceae and Hyphomicrobiaceae. As intensive disinfection is applied at worldwide wastewater treatment plants during COVID-19, carbon source facilitated denitrification should be better managed to reduce both effluent inorganic nitrogen and DON, mitigating DON and N-DBP associated ecological risks in receiving waters.

A process-based model for describing redox kinetics of Cr(VI) in natural sediments containing variable reactive Fe(II) species

Sediment-associated Fe(II) is a critical reductant for immobilizing groundwater contaminants, such as Cr(VI). The reduction reactivity of sediment-associated Fe(II) is dependent on its binding environment and influenced by the biogeochemical transformation of other elements (i.e., C, N and Mn), challenging the description and prediction of the reactivity of Fe(II) in natural sediments. Here, anaerobic batch experiments were conducted to study the variation in sediment-associated Fe(II) reactivity toward Cr(VI) in natural sediments collected from an intensive agricultural area located in Guangxi, China, where nitrate is a common surface water and groundwater contaminant. Then, a process-based model was developed to describe the coupled biogeochemical processes of C, N, Mn, Fe, and Cr. In the process-based model, Cr(VI) reduction by sediment-associated Fe(II) was described using a previously developed multirate model, which categorized the reactive Fe(II) into three fractions based on their extractabilities in sodium acetate and HCl solutions. The experimental results showed that Fe(II) generation was inhibited by NO₃^- and/or NO₂^-. After NO₃^- and NO₂^- were exhausted, the Fe(II) content and its reduction rate toward Cr(VI) increased rapidly. As the Fe(II) content increased, the three reactive Fe(II) fractions exhibited approximately linear correlations with aqueous Fe(II) concentrations ( [Formula: see text] ), which was probably driven by sorptive equilibrium and redox equilibrium between aqueous and solid phases. The model results indicated that the reaction rate constants of the three Fe(II) fractions (k_n) significantly increased with incubation time, and log(k_n) correlated well with [Formula: see text] [ [Formula: see text] , [Formula: see text] and [Formula: see text] ]. The numerical model developed in this study provides an applicable method to describe and predict Cr(VI) removal from groundwater under dynamic redox conditions.

Microbial Fuel Cell-Based Biosensor for Simultaneous Test of Sodium Acetate and Glucose in a Mixed Solution

Most microbial fuel cell (MFC) sensors only focus on the detection of mixed solutions with respect to the chemical oxygen demand (COD) or toxicity; however, the concentrations of the individual analytes in a mixed solution have rarely been studied. Herein, we developed two types of MFC sensors, adapted with sodium acetate (MFC-A) and glucose (MFC-B) as organic substrates in the startup period. An evident difference in the sensor sensitivities (the slope value of the linear-regression curve) was observed between MFC-A and MFC-B. MFC-A exhibited a superior performance compared with MFC-B in the detection of sodium acetate (4868.9 vs. 2202 mV/(g/L), respectively) and glucose (3895.5 vs. 3192.9 mV/(g/L), respectively). To further compare these two MFC sensors, the electrochemical performances were evaluated, and MFC-A exhibited a higher output voltage and power density (593.76 mV and 129.81 ± 4.10 mW/m², respectively) than MFC-B (484.08 mV and 116.21 ± 1.81 mW/m², respectively). Confocal laser scanning microscopy (CLSM) and microbial-community analysis were also performed, and the results showed a richer anode biomass of MFC-A in comparison with MFC-B. By utilizing the different sensitivities of the two MFC sensors towards sodium acetate and glucose, we proposed and verified a novel method for a simultaneous test on the individual concentrations of sodium acetate and glucose in a mixed solution. Linear equations of the two variables (concentrations of sodium acetate and glucose) were formulated. The linear equations were solved according to the output voltages of the two MFC sensors, and the solutions showed a satisfactory accuracy with regard to sodium acetate and glucose (relative error less than 20%).

[Effects of External Carbon Sources on Ultimate Nitrogen Removal Performance and Microbial Community in Secondary Effluent Treating Process]

Adding external carbon sources is an important method for advanced nitrogen removal of secondary effluent in wastewater treatment plants (WWTPs). In order to compare the denitrification performance and economy of different carbon sources sufficiently, as well as the effect of long-term addition of carbon sources on the microbial population structure, four single carbon sources (methanol, ethanol, glucose, and sodium acetate) and four types of composite carbon sources were prepared by mixing sodium acetate and ethanol with a higher reaction rate and cheap glucose. The results showed that the effluent ρ(NO_x^--N) concentration of all systems was less than 1.0 mg·L^-1 during the experiment. For single-carbon source systems, ethanol had the fastest denitrification rate, followed by sodium acetate and methanol; that of the glucose was the slowest. In the composite carbon source systems, the sodium acetate/glucose (1:1) with COD/ρ(N) was 6, which was equivalent to the results of sodium acetate/glucose (1:3), ethanol/glucose(1:1), and ethanol/glucose (1:3) with COD/ρ(N) of 9, 10, and 10, respectively. The sodium acetate/glucose (1:1) system had the fastest reaction rate and the best economy. High-throughput sequencing results showed that after more than 70 days of operation, the structure of the microbial community had changed completely. In the glucose-related system, the abundance of Candidatus Saccharibacteria, which is not popular in typical nitrogen removal systems, increased from 1.16% of seed sludge to 47.37%, and Saccharibacteria_genera_incertae_sedis correspondingly became the dominant community. This study not only provides a more comprehensive comparison for the selection of carbon sources in WWTPs with ultimate nitrogen removal but also provides basic data for the role of carbon sources in the domestication of microbial communities.

Effect of carbon source conditions on response of nitrifying sludge to 3,5-dichlorophenol

Nutritional conditions of activated sludge had a significant influence on nitrification inhibition response. This study comprehensively investigated the inhibition of 3,5-dichlorophenol (3,5-DCP) on nitrification of activated sludge with different C/N ratios and carbon source types. The corresponding extracellular polymeric substances (EPS), microbial communities and functional genes were analysed. The results indicated that the addition of carbon source would reduce the nitrification activity and nitrification sensitivity to 3,5-DCP, and the order of the EC₅₀ was sequenced as sodium acetate > methanol > glucose. The response mechanisms of activated sludge under diverse carbon source conditions to 3,5-DCP were summarised as follows. When the 3,5-DCP content was increased from 0.4 mg/L to 0.8 mg/L, the protein content increased from 73.2 ± 2.6 mg/g SS ∼122.4 ± 4 mg/g SS to 92.2 ± 11.2 mg/g SS ∼130.8 ± 9.6 mg/g SS in the tightly bound EPS (TB-EPS). The increase of protein content was attributed to cellular self-protection mechanisms. Furthermore, fluorescence characteristic analysis revealed that tyrosine and tryptophan in loosely bound EPS (LB-EPS) might account for higher EC₅₀ in activated sludge fed with methanol and sodium acetate. In addition, the redundancy analyses (RDA) showed activated sludge with organics enriched the resistant species, such as Proteobacteria and Patescibacteria, while activated sludge without organics enriched the sensitive species, such as Ferruginibacter. Finally, the nitrification genes were found to be consistent with nitrification activity. Thus, the findings provide new insights into nitrification inhibition mechanism under different carbon source conditions.

Influence of Carbon Sources on Biomass and Biomolecule Accumulation in Picochlorum sp. Cultured under the Mixotrophic Condition

The major downfalls of the microalgal biorefinery are low volume of high value product accumulation, low biomass productivity and high cultivation costs. Here, we aimed to improve the biomass productivity of the industrially relevant Picochlorum sp. BDUG 100241 strain. The growth of Picochlorum sp. BDUG 100241 was investigated under different cultivations conditions, including photoautotrophic (with light), mixotrophic (1% glucose, with light) and heterotrophic (1% glucose, without light). Among them, Picochlorum sp. BDUG100241 showed the highest growth in the mixotrophic condition. Under different (1%) carbon sources’ supplementation, including glucose, sodium acetate, glycerol, citric acid and methanol, Picochlorum sp. BDUG100241 growth was tested. Among them, sodium acetate was found to be most suitable carbon source for Picochlorum sp. BDUG 100241 growth, biomass (1.67 ± 0.18 g/L) and biomolecule productivity. From the different concentrations of sodium acetate (0, 2.5, 5.0, 7.5 and 10 g/L) tested, the maximum biomass production of 2.40 ± 0.20 g/L with the biomass productivity of 95 ± 5.00 mg/L/d was measured from 7.5 g/L in sodium acetate. The highest total lipid (53.50 ± 1.70%) and total carotenoids (0.75 ± 0.01 µg/mL) contents were observed at the concentration of 7.5 g/L and 5.0 g/L of sodium acetate as a carbon source, respectively. In conclusion, the mixotrophic growth condition containing 7.5 g/L of sodium acetate showed the maximum biomass yield and biomolecule accumulation compared to other organic carbon sources.

Multicentre randomised controlled trial: protocol for Plasma-Lyte Usage and Assessment of Kidney Transplant Outcomes in Children (PLUTO)

INTRODUCTION

Acute electrolyte and acid-base imbalance is experienced by many children following kidney transplantation. When severe, this can lead to complications including seizures, cerebral oedema and death. Relatively large volumes of intravenous fluid are administered to children perioperatively in order to establish perfusion to the donor kidney, the majority of which are from living and deceased adult donors. Hypotonic intravenous fluid is commonly used in the post-transplant period due to clinicians' concerns about the sodium, chloride and potassium content of isotonic alternatives when administered in large volumes.Plasma-Lyte 148 is an isotonic, balanced intravenous fluid that contains sodium, chloride, potassium and magnesium with concentrations equivalent to those of plasma. There is a physiological basis to expect that Plasma-Lyte 148 will reduce the incidence of clinically significant electrolyte and acid-base abnormalities in children following kidney transplantation compared with current practice.The aim of the Plasma-Lyte Usage and Assessment of Kidney Transplant Outcomes in Children (PLUTO) trial was to determine whether the incidence of clinically significantly abnormal plasma electrolyte levels in paediatric kidney transplant recipients will be different with the use of Plasma-Lyte 148 compared with intravenous fluid currently administered.

METHODS AND ANALYSIS

PLUTO is a pragmatic, open-label, randomised controlled trial comparing Plasma-Lyte 148 to current care in paediatric kidney transplant recipients, conducted in nine UK paediatric kidney transplant centres.A total of 144 children receiving kidney transplants will be randomised to receive either Plasma-Lyte 148 (the intervention) intraoperatively and postoperatively, or current fluid. Apart from intravenous fluid composition, all participants will receive standard clinical transplant care.The primary outcome measure is acute hyponatraemia in the first 72 hours post-transplant, defined as laboratory plasma sodium concentration of <135 mmol/L. Secondary outcomes include symptoms of acute hyponatraemia, other electrolyte and acid-base imbalances and transplant kidney function.The primary outcome will be analysed using a logistic regression model adjusting for donor type (living vs deceased donor), patient weight (<20 kg vs ≥20 kg pretransplant) and transplant centre as a random effect.

ETHICS AND DISSEMINATION

The trial received Health Research Authority approval on 20 January 2020. Findings will be presented to academic groups via national and international conferences and peer-reviewed journals. The patient and public involvement group will play an important part in disseminating the study findings to the public domain.

TRIAL REGISTRATION NUMBERS

2019-003025-22 and 16586164.

Optimized production of xylooligosaccharides from poplar: A biorefinery strategy with sequential acetic acid/sodium acetate hydrolysis followed by xylanase hydrolysis

The preparation of xylooligosaccharides (XOS) from lignocelluloses by organic acid hydrolysis has the advantages of high efficiency and simplicity, but reducing the production of by-products, especially xylose, is a prerequisite for commercial preparation of XOS using organic acid. In this work, to reduce the production of by-products, the acetic acid/sodium acetate conjugate system (AC/SA) was used to prepare XOS from poplar. Under the optimal conditions (0.15 M AC/SA, molar ratio of 3.0, 175 °C, 60 min), the maximum XOS yield was 33.6% with a low xylose/XOS ratio of 0.19. Xylanase hydrolysis effectively converted XOS with DP above 6 in the AC/SA hydrolysate to X2-X6 with little xylose produced. The XOS yield increased to 42.1%, with a xylose/XOS ratio was only 0.17. This work shows that AC/SA in combination with xylanase hydrolysis of poplar successfully achieved high XOS yield with low by-products yields without the extraction of xylan from the substrate.

Enhanced bioremediation of sediment contaminated with polycyclic aromatic hydrocarbons by combined stimulation with sodium acetate/phthalic acid

In this study, four groups of laboratory scale experiments were performed by adding sodium acetate (SA), phthalic acid (PA), and SA-PA to river sediment to observe the microbial response and biodegradation efficiency of polycyclic aromatic hydrocarbons (PAHs). The results showed that the amount of total organic carbon consumed and the amount of sulfate reduction were both positively correlated (p < 0.01) with the biodegradation efficiency of the sum (∑) PAHs (∼40.5%). The lower the number of rings, the more PAHs were biodegraded, with an efficiency of 63.0% for ∑ (2 + 3) ring PAHs. Based on high-throughput sequencing and molecular ecological network analysis, it was found that the combined stimulation of SA and PA not only increased the relative abundance of PAHs-degrading bacterial (eg., Proteobacteria, Desulfobacterota, Campilobacterota and Firmicutes), but also had a strengthening effect on microbes in sediments. The altered microbial structure caused a variation in metabolic functions, which increased the amino acid metabolism to 12.2%, thus increasing the positive correlations among genera and improving the connectivity of the microbial network (p < 0.01). These changes may be responsible for the enhanced biodegradation of PAHs under SA-PA dosing in comparison to SA or PA dosing alone. This study revealed that the microbial community was stimulated by the combined addition of SA and PA, and indicated its role in enhancing biodegradation of PAHs in contaminated river sediments.

Two-step acetic acid/sodium acetate and xylanase hydrolysis for xylooligosaccharides production from corncob

At present, xylooligosaccharides (XOS) from corncob using acid-base conjugate system has not been reported. In this study, XOS production from corncob by two-step acetic acid/sodium acetate (AC/SA) conjugate system hydrolysis and xylanase hydrolysis was optimized, and monosaccharides were subsequently produced from corncob residues by cellulase hydrolysis. The XOS of 19.9 g/L was obtained from corncob (10%, w/v) using 0.15 M AC/SA hydrolysis at a molar ratio of 3.0 at 170 °C for 60 min, followed by xylanase hydrolysis. The second-step AC/SA hydrolysis of hydrolyzed corncob (10%, w/v) produced 3.1 g/L of XOS. Finally, the maximum XOS yield of 74.8% (based on xylan in corncob) was achieved, which is the highest yield among yields reported previously. The purity of XOS was high, whereas the contents of by-products were very low. This work presents a novel and promising strategy for co-production of XOS and monosaccharides from corncob without xylan isolation and purification.

Could co-substrate sodium acetate simultaneously promote Chlorella to degrade amoxicillin and produce bioresources?

Integrating microalgae culture and wastewater purification is a promising technology for sustainable bioresource production. However, the challenge is that toxins in wastewater usually limit risk elimination and cause poor bioresource production. Easy-to-biodegrade substrates could alleviate the resistant stress on a bacterial community but we know little about how they function with microalgae. In this study, we tested if Easy-to-biodegrade substrates could simultaneously promote Chlorella to degrade antibiotic amoxicillin (AMO) and produce bioresources. Sodium acetate (NaAC) was used as the representative co-substrate. The results showed NaAC could enhance AMO removal by 76%. The β-lactam structure was destroyed and detoxified to small molecules, due to the up-regulation of hydrolase, oxidoreductase, reductase, and transferase. Chlorella biomass production increased by 36%. The genes encoding the glutathione metabolism and peroxisome pathways were significantly up-regulated to alleviate the antibiotic stress, and the DNA replication pathway was activated. As a result, the production of lipid, carbohydrate, and protein was enhanced by 61%, 122%, and 34%, respectively. This study provides new insights for using microalgae to recover bioresources from toxic wastewater and reveals the critical underlying mechanisms.

Isolation of a Novel Polyketide from Neodidymelliopsis sp

Fungi have become an invaluable source of bioactive natural products, with more than 5 million species of fungi spanning the globe. Fractionation of crude extract of Neodidymelliopsis sp., led to the isolation of a novel polyketide, (2Z)-cillifuranone (1) and five previously reported natural products, (2E)-cillifuranone (2), taiwapyrone (3), xylariolide D (4), pachybasin (5), and N-(5-hydroxypentyl)acetamide (6). It was discovered that (2Z)-cillifuranone (1) was particularly sensitive to ambient temperature and light resulting in isomerisation to (2E)-cillifuranone (2). Structure elucidation of all the natural products were conducted by NMR spectroscopic techniques. The antimicrobial activity of 2, 3, and 5 were evaluated against a variety of bacterial and fungal pathogens. A sodium [1-¹³C] acetate labelling study was conducted on Neodidymelliopsis sp. and confirmed that pachybasin is biosynthesised through the acetate polyketide pathway.

Simultaneously enhanced intracellular lipogenesis and β-carotene biosynthesis of Rhodotorula glutinis by light exposure with sodium acetate as the substrate

In this study, light exposure was applied to simultaneously enhance lipogenesis and β-carotene biosynthesis of Rhodotorula glutinis with sodium acetate as the sole carbon source. The results showed that cell growth, intracellular lipogenesis and carotene biosynthesis were improved with an optimal exposure condition at 10 g/L and 20 g/L sodium acetate. Under high light exposure condition (8000 lx), cell growth and lipid production were inhibited while β-carotene accumulation was promoted. The fatty acid compositions moreover revealed that more polyunsaturated fatty acids and linoleic acid were generated under light exposure, which demonstrated its crucial role in the oxidative stress resistance in R. glutinis. The expression levels of some genes in acetate consumption, lipogenesis and β-carotene biosynthesis were found significantly upregulated under light exposure. The results proved that light exposure could be applied as an effective method to improve lipid and β-carotene production with sodium acetate as the substrate in R. glutinis.

Effect of Balanced Crystalloid, Gelatin and Hydroxyethyl Starch on Coagulation Detected by Rotational Thromboelastometry In Vitro

BACKGROUND

Fluid resuscitation with crystalloid and colloid solutions is a common treatment in perioperative medicine. However, a variety of unbalanced or balanced solutions are used in clinical practice and there is still vivid debate going on regarding selection of optimal fluid with minimal negative effect on coagulation to minimize bleeding and blood transfusion requirements. The aim of the study was to investigate adverse effects of balanced crystalloids and colloids on coagulation measured by thromboelastometry in vitro.

METHODS

Blood samples were obtained from healthy volunteers undergoing knee arthroscopy. Adverse effects of balanced crystalloid, hydroxyethyl starch, and gelatin were evaluated by thromboelastometry after 20% dilution of blood with the solution in vitro. Parameters of EXTEM and FIBTEM test were evaluated.

RESULTS

Clotting time of EXTEM was not significantly influenced by any of the investigated solutions (p > 0.05). However, significant impairment of clot formation time of EXTEM was detected in hydroxyethyl starch and gelatin groups in comparison with controls (p < 0.05), while crystalloid did not affect this parameter significantly (p > 0.05). Similar results were found in α angle although significant coagulopathy effect was found only in hydroxyethyl starch samples (p < 0.05). Maximum clot firmness of EXTEM and FIBTEM tests was significantly affected by both hydroxyethyl starch and gelatin (p < 0.05) but not by crystalloid.

CONCLUSIONS

Balanced crystalloid solution does not seem to have a negative influence on the coagulation process as measured by thromboelastometry. On the other hand, balanced colloids may impair propagation phase of coagulation, strength of coagulum, and level of functional fibrinogen. Hydroxyethyl starch seems to have a stronger anticoagulant effect compared to gelatin.

[Effects of Long-term Poly-P Deficiency on the Metabolic Properties of Accumulibacter in AO-SBR System]

To investigate the changes in microbial community structure and metabolic properties of Accumulibacter under long-term Poly-P deficiency, an activated sludge enriched with Accumulibacter was inoculated into two SBR reactors, where sodium acetate and sodium propionate were used separately as organic carbon sources. The two reactors were operated for 60 days with an influent PO₄^3--P concentration of 2.5 mg·L^-1. The phosphorus removal performance, sludge production, and changes in the microbial community structure of the systems were analyzed. The results indicated that both SBR systems showed good performance of phosphorus and organic matter removal. However, microorganisms in both systems showed glycogen-accumulating metabolism properties under long-term Poly-P deficiency. In the unfavorable environment of long-term Poly-P deficiency, Accumulibacter Ⅰ maintained a high abundance (40%±7%) in the propionate SBR system, indicating that Accumulibacter Ⅰ had higher metabolic activity and its metabolic properties could be independent of Poly-P for survival under Poly-P deficiency for a long period. In comparison, propionate is more conducive to Accumulibacter adaptation to lower phosphorus loads, and Accumulibacter Ⅰ is more competitive than Accumulibacter Ⅱ under lower phosphorus loads.

[Nitrite Accumulation Characteristics of Partial Denitrification in Different Sludge Sources Using Sodium Acetate as Carbon Source]

In order to explore the characteristics of nitrite accumulation during the operational period of partial denitrification in different sludge sources using sodium acetate as a carbon source, No.1 SBR and No.2 SBR were used to inoculate with surplus sludge taken separately from a secondary sedimentation tank of a sewage treatment plant and simultaneous nitrification and denitrifying phosphorus removal system. By reasonably controlling the initial nitrate concentration and anoxic time, partial denitrification was realized. The carbon and nitrogen removal characteristics under different initial COD and NO₃^--N concentrations were investigated. The results showed that, using sodium acetate as the carbon source, the partial denitrification process in No.1 SBR and No.2 SBR sludge successfully began in 21 d and 20 d, respectively. The accumulation of NO₂^--N and nitrite accumulation rate (NAR) in reactors were maintained at high levels (12.61 mg·L^-1, 79.76% and 13.85 mg·L^-1, 87.60%, respectively). When the initial NO₃^--N concentration of No.2 SBR was 20 mg·L^-1 and the initial COD concentration increased from 60 mg·L^-1 to 140 mg·L^-1, the operation time for achieving the highest NO₂^--N accumulation in the system was shortened from 160 min to 6 min. The NO₃^--N ratio of the denitrification rate (in VSS) increased from 3.84 mg·(g·h)^-1 to 7.35 mg·(g·h)^-1. Increased initial COD concentration was beneficial to the accumulation of NO₂^--N during partial denitrification. When the initial COD concentration of No.2 SBR was 100 mg·L^-1 and the initial NO₃^--N concentration increased from 20 mg·L^-1 to 30 mg·L^-1, NAR was maintained above 90% and up to 100% (the initial NO₃^--N concentration was 25 mg·L^-1). When the initial NO₃^--N concentration was ≥ 35 mg·L^-1, insufficient COD caused NO₃^--N to be completely reduced to NO₂^--N. Under different initial COD concentrations (80, 100, or 120 mg·L^-1) and different initial NO₃^--N concentrations (20, 25, 30, or 40 mg·L^-1), the nitrogen and carbon removal and partial denitrification performance of the No.2 SBR was better than that of No.1 SBR.

Effect of saline 0.9% or Plasma-Lyte 148 therapy on feeding intolerance in patients receiving nasogastric enteral nutrition

OBJECTIVE

To compare the effect of Plasma-Lyte (PL)-148 and saline 0.9% (saline) on gastrointestinal (GI) feeding intolerance in mechanically ventilated patients receiving nasogastric (NG) feeding in an intensive care unit.

DESIGN AND SETTING

A single-centre pilot study, nested within a multicentre, double-blind, cluster-randomised, double-crossover trial, performed in a mixed medical and surgical ICU.

PARTICIPANTS

All adult patients who required crystalloid fluid therapy as part of the 0.9% Saline versus Plasma-Lyte 148 for Intensive Care Unit Fluid Therapy (SPLIT) trial, were expected to need mechanical ventilation for more than 48 hours and were receiving enteral nutrition exclusively by NG tube were eligible. We enrolled 69 patients and assigned 35 to PL-148 and 34 to saline.

INTERVENTIONS

We randomly allocated saline or PL-148 for four alternating 7-week blocks, with staff blinded to the solution.

MAIN OUTCOME MEASURES

The primary outcome was the proportion of patients with GI feeding intolerance, defined as high gastric residual volume (GRV), diarrhoea or vomiting while receiving NG feeding in the ICU. The proportions of patients with each of high GRV, diarrhoea and vomiting were secondary outcomes.

RESULTS

In the PL-148 group, 21 of 35 patients (60.0%) developed GI feeding intolerance, compared with 22 of 34 patients (64.7%) in the saline group (odds ratio [OR], 0.82; 95% CI, 0.31-2.17; P = 0.69). A high GRV was seen in four of 35 patients (11.4%) in the PL-148 group, and in 11 of 34 patients (32.4%) in the saline group (OR, 0.27; 95% CI, 0.08-0.96; P = 0.04).

CONCLUSION

Among mechanically ventilated patients receiving NG feeding, the use of PL-148, compared with saline, did not reduce the proportion of patients developing GI feeding intolerance, but was associated with a decreased incidence of high GRV.

Evaluation of the ecotoxicological impact of the organochlorine chlordecone on soil microbial community structure, abundance, and function

The insecticide chlordecone applied for decades in banana plantations currently contaminates 20,000 ha of arable land in the French West Indies. Although the impact of various pesticides on soil microorganisms has been studied, chlordecone toxicity to the soil microbial community has never been assessed. We investigated in two different soils (sandy loam and silty loam) exposed to different concentrations of CLD (D0, control; D1 and D10, 1 and 10 times the agronomical dose) over different periods of time (3, 7, and 32 days): (i) the fate of chlordecone by measuring (14)C-chlordecone mass balance and (ii) the impact of chlordecone on microbial community structure, abundance, and function, using standardized methods (-A-RISA, taxon-specific quantitative PCR (qPCR), and (14)C-compounds mineralizing activity). Mineralization of (14)C-chlordecone was inferior below 1 % of initial (14)C-activity. Less than 2 % of (14)C-activity was retrieved from the water-soluble fraction, while most of it remained in the organic-solvent-extractable fraction (75 % of initial (14)C-activity). Only 23 % of the remaining (14)C-activity was measured in nonextractable fraction. The fate of chlordecone significantly differed between the two soils. The soluble and nonextractable fractions were significantly higher in sandy loam soil than in silty loam soil. All the measured microbiological parameters allowed discriminating statistically the two soils and showed a variation over time. The genetic structure of the bacterial community remained insensitive to chlordecone exposure in silty loam soil. In response to chlordecone exposure, the abundance of Gram-negative bacterial groups (β-, γ-Proteobacteria, Planctomycetes, and Bacteroidetes) was significantly modified only in sandy loam soil. The mineralization of (14)C-sodium acetate and (14)C-2,4-D was insensitive to chlordecone exposure in silty loam soil. However, mineralization of (14)C-sodium acetate was significantly reduced in soil microcosms of sandy loam soil exposed to chlordecone as compared to the control (D0). These data show that chlordecone exposure induced changes in microbial community taxonomic composition and function in one of the two soils, suggesting microbial toxicity of this organochlorine.

[Experimental Conditions and Reliability Analysis of Results of COD components]

The present study attempts to use SF( OUR(max)/OUR(en)) instead of S(0)/X(0) as an index of optimal initial conditions for determination of COD components by means of respirometry, thereby simplifying the measuring process and the operation can be automated. Further, the ratio of COD consumed by the growth of biomass can be used for the reliability assessment of results. Experimental results show that, experimental conditions for obtaining good results as follows: (1) for samples that composed of a large amount of easily biodegradable components (e. g., synthetic wastewater made by sodium acetate), SF should be in the range of 2.8 to 5.3, and the ratio of COD consumed by growth of biomass should be less than 30%; (2) for samples that composed of both readily biodegradable and slowly biodegradable components (i. e., typical domestic wastewater), SF should be in the range of 5.8 to 6.4, and the ratio of COD consumed by growth of biomass should be less than 30%; (3) and for samples that composed of a large amount of slowly biodegradable industrial wastewater (i. e., landfill leachate), SF should be 15 or less, and the ratio of COD consumed by growth of biomass should be approximately 40%. Therefore, when respirometry is used for the determination of COD components, the optimal conditions in terms of SF increase with the complexity of carbon source.

Agreement of the Kato-Katz test established by the WHO with samples fixed with sodium acetate analyzed at 6 months to diagnose intestinal geohelminthes

The aim of this study was to evaluate the performance of the Kato-Katz test (WHO version) with stool samples from a rural area, fixed with sodium acetate (SAF). The Kato-Katz test was used to compare unfixed samples (conventional test) with the same samples containing SAF fixative at time 0 and at 6 months. The study included stools from 154 subjects. A marginally statistically significant decrease in prevalence was estimated only for hookworm, when comparing unfixed samples versus the SAF fixed samples read at 6 months (p=0.06). A significant reduction in parasite load was found for hookworm (p<0.01) and Trichuris trichiura (p<0.01) between the unfixed and the fixed sample read at 6 months, but not for Ascaris lumbricoides (p=0.10). This research suggests that the SAF fixative solution is a good option for transporting samples for diagnosis, especially in rural areas in developing countries.

Impact of carbon source on nitrous oxide emission from anoxic/oxic biological nitrogen removal process and identification of its emission sources

Wastewater treatment is an important source of nitrous oxide (N(2)O), which is a strong greenhouse gas and dominate ozone-depleting substance. The purpose of this study was to evaluate the effect of carbon source on N(2)O emission from anoxic/oxic biological nitrogen removal process. The mechanisms of N(2)O emission were also studied. Long-term experiments were operated to evaluate the effect of three different carbon sources (i.e., glucose, sodium acetate, and soluble starch) on N(2)O emission characteristics. And batch experiments, in the presence or absence of specific inhibitors, were carried out to identify the sources of N(2)O emission. The ammonia-oxidizing bacteria (AOB) and denitrifiers community compositions under different circumstances were also analyzed based on which the underlying mechanisms of N(2)O emission were elucidated. The conversion ratios of N(2)O in reactors with glucose, sodium acetate, and soluble starch were 5.3 %, 8.8 %, and 2.8 %, respectively. The primary process responsible for N(2)O emission was nitrifier denitrification by Nitrosomonas-like AOB, while denitrification by heterotrophic denitrifiers acted as the sink. Reactor with sodium acetate showed the highest N(2)O emission, together with the highest nitrogen and phosphate removal ratios. Carbon source has a significant impact on N(2)O emission quantity and relatively minor effect on its production mechanism.

Characteristics and photo-responsive release property of liposome containing 7-acetoxy coumarin

A photo-responsive liposome was developed by loading 7-acetoxy coumarin (ATC) in egg phosphatidylcholine (EPC) liposome. ATC was derivetized from 7-hydroxy coumarin using sodium acetate. The ATC-loaded liposomes were prepared by suspending the dry mixture film of ATC/EPC in distilled water and sonicating the suspension. When the ATC to EPC ratio was less than 1:8, homogeneous liposomal suspensions were obtained without any precipitate. On 1H NMR spectra, the unsaturated chains of liposomal EPCs were somewhat deteriorated by a subsequent irradiation, the irradiation of lambda = 365 nm and then the irradiation of lambda = 254 nm. On TEM photos, the size of liposomes incorporating ATC markedly increased by the subsequent irradiation. Photo-dimerization (under lambda = 365 nm) and de-dimerization (under lambda = 254 nm) of ATC took a place even in EPC liposomes. Upon the irradiation of lambda = 254 nm, liposome containing ATC dimers exhibited an enhanced release of 5(6)-carboxyfluorescein compared with liposome containing ATC monomer and liposome free of ATC. The de-dimerization of ATC dimers is believed to fluidize the liposomal membrane and promote the release.

Gustatory feedback affects feeding related motor pattern generation in starved 3rd instar larvae of Calliphora vicina

Gustatory feedback allows animals to distinguish between edible and noxious food and adapts centrally generated feeding motor patterns to environmental demands. In reduced preparations obtained from starved Calliphora larvae, putatively appetitive (ethanol), aversive (sodium acetate) and neutral (glucose) gustatory stimuli were applied to the anterior sense organs. The resulting sensory response was recorded from the maxillary and antennal nerves. All three stimuli increased the neural activity in both nerves. Recordings obtained from the antennal nerve to monitor the activation pattern of the cibarial dilator muscles, demonstrated an effect of gustatory input on the central pattern generator for feeding. Ethanol consistently enhanced the rhythmic activity of the CDM motor neurons either by speeding up the rhythm or by increasing the burst duration. Ethanol also had an enhancing effect on the motor patterns of a protractor muscle which moves the cephalopharyngeal skeleton relative to the body. Sodium acetate showed a state dependent effect: in preparations without spontaneous CDM activity it initiated rhythmic motor patterns, while an ongoing CDM rhythm was inhibited. Surprisingly glucose had an enhancing effect which was less pronounced than that of ethanol. Gustatory feedback therefore can modify and adapt the motor output of the multifunctional central pattern generator for feeding.

[Studies on NACE-DAD fingerprint of Cortex Phellodendri]

OBJECTIVE

To establish the analytical method for the fingerprint of Cortex Phellodendri by NACE-DAD and estimate the quality of Cortex Phellodendri from different habitats and species.

METHODS

Based on the mode of nonaqueous capillary electrophoresis, 40 mmol/L sodium acetate and 40 mmol/L ammonium acetate methanol solution was selected for the buffer (pH 5.8). The separation voltage was 25 kV and detection wavelength was set at 210 nm. Berberine was used as a reference standard, the chromatographic fingerprint was determined. The data were analysed by Fuzzy Cluster and Fingerprint Similarity Evaluation Software to compare the similarity of samples.

RESULTS

NACE-DAD fingerprints with 9 common peaks were established preliminarily. It was discovered that a small number of samples differed from others. Regarding to the fingerprints of Cortex Phellodendri and its processed products, there were obvious differences in the relative areas of common peaks.

CONCLUSION

The method is reliable, accurate and can be used for quality control of Cortex Phellodendri.

Inhibition effects on fermentation of hardwood extracted hemicelluloses by acetic acid and sodium

Extraction of hemicellulose from hardwood chips prior to pulping is a possible method for producing ethanol and acetic acid in an integrated forest bio-refinery, adding value to wood components normally relegated to boiler fuel. Hemicellulose was extracted from hardwood chips using green liquor, a pulping liquor intermediate consisting of aqueous NaOH, Na(2)CO(3), and Na(2)S, at 160 degrees C, held for 110 min in a 20 L rocking digester. The extracted liquor contained 3.7% solids and had a pH of 5.6. The organic content of the extracts was mainly xylo-oligosaccharides and acetic acid. Because it was dilute, the hemicellulose extract was concentrated by evaporation in a thin film evaporator. Concentrates from the evaporator reached levels of up to 10% solids. Inhibitors such as acetic acid and sodium were also concentrated by this method, presenting a challenge for the fermentation organisms. Fermentation experiments were conducted with Escherichia coli K011. The un-concentrated extract supported approximately 70% conversion of the initial sugars in 14 h. An extract evaporated down to 6% solids was also fermentable while a 10% solids extract was not initially fermentable. Strain conditioning was later found to enable fermentation at this level of concentration. Alternative processing schemes or inhibitor removal prior to fermentation are necessary to produce ethanol economically.

Gastric emptying before and after cholecystectomy in patients with cholecystolithiasis

BACKGROUND/AIMS

The objective of the present study was to measure gastric emptying time of solids and semisolids in dyspeptic individuals with cholecystolithiasis before and 6 months after cholecystectomy in order to determine whether cholecystectomy interferes with gastric emptying.

METHODOLOGY

A prospective, self-pairing study was conducted on 29 patients selected according to appropriate inclusion and exclusion criteria. Gastric emptying time of solids and semisolids was determined before and six months after laparoscopic cholecystectomy by the 13C-octanoic acid and 13C-acetate breath tests, respectively. The samples were analyzed by infrared spectrometry. The gastric retention time (lag phase) and gastric emptying half-time of solid and semisolid were determined and the results obtained before and after surgery were compared in the same patient. In addition, the effects of surgery on dyspeptic symptoms were assessed.

RESULTS

No significant differences (p>0.05) in gastric retention time and gastric emptying half-time of solid and semisolid test meals were observed before and after cholecystectomy. Dyspeptic symptoms (pain, upper abdominal gases, early satiety, nausea and vomiting) improved after surgery.

CONCLUSIONS

Laparoscopic cholecystectomy does not interfere with the gastric emptying time of solids or semisolids in dyspeptic individuals with cholecystolithiasis.

Modulation of Caenorhabditis elegans chemotaxis by cultivation and assay temperatures

The chemotaxis behaviors of the nematode Caenorhabditis elegans cultivated at various temperatures (15 degrees C, 20 degrees C and 25 degrees C) were examined at various temperatures (10 degrees C, 15 degrees C, 20 degrees C and 25 degrees C) to determine the multi-sensory integration of physical (thermal) and chemical sensory information within its nervous system. Chemotaxis behavior toward sodium acetate and ammonium chloride were differently affected by both assay and cultivation temperatures, suggesting that the temperature effect on chemotaxis is not general, but rather distinctive for each chemosensory pathway. Since thermosensory cues are likely encountered constantly in C. elegans, we supposed that the chemotaxis behaviors of worms are achieved by the integration of chemo- and thermosensory information. To verify the possible contribution of thermosensory function in chemotaxis, we examined the chemotaxis behaviors of ttx-1(p767) mutant worms with defective AFD thermosensory neurons. The chemotaxis behaviors toward sodium acetate or ammonium chloride of mutant worms cultivated at 20 degrees C and 25 degrees C were reduced relative to those of wild-type worms. These results indicate the important role of multi-sensory integration of chemosensory and thermosensory information in chemotaxis behavior of the C. elegans.

Extraction of plant RNA

This protocol details an RNA preparation for medium-scale, high-purity RNA production from higher plants. It uses hot acid phenol with standard sodium acetate ethanol precipitation and is suitable for producing RNA for both Northern blotting and enzyme-based downstream applications such as RT-PCR and microarray studies.