Effect of monocultures and polycultures of Typha latifolia and Heliconia psittacorum on the treatment of river waters contaminated with landfill leachate/domestic wastewater in partially saturated vertical constructed wetlands.

Partially Saturated Vertical Constructed Wetlands (PSV-CWs) are novel wastewater treatment systems that work through aerobic and anaerobic conditions that favor the removal of pollutants found in high concentrations, such as rivers contaminated with domestic wastewater and landfill leachate. The objective of the study was to evaluate the efficiency of PSV-CWs using monocultures and polycultures of Typha latifolia and Heliconia psittacorum to treat river waters contaminated with leachates from open dumps and domestic wastewater. Six experimental units of PSV-CWs were used; two were planted with Typha latifolia monoculture, two with Heliconia psittacorum monoculture and two with polycultures of both plants. The results indicated better organic matter and nitrogen removal efficiencies (p < 0.05) in systems with polycultures (TSS:95%, BOD5:83%, COD:89%, TN:82% and NH4+:99%). In general, the whole system showed high average removal efficiencies (TSS:93%, BOD5:79%, COD:85%, TN:79%, NH4+:98% and TP:85%). Regarding vegetation, both species developed better in units with monocultures, being Typha latifolia the one that reached a more remarkable development. However, both species showed high resistance to the contaminated environment. These results showed higher removals than those reported in the literature with conventional Free Flow Vertical Constructed Wetlands (FFV-CWs), so PSV-CWs could be a suitable option to treat this type of effluent.

The research addresses the contamination of water resources in developing countries by landfill leachate and domestic wastewater discharges. It proposes treatment through Partially Saturated Vertical Constructed Wetlands (PSV-CWs), which, despite the limited information available, have been shown to be effective in removing pollutants in effluents with high concentrations. In addition to evaluating PSV-CWs, the study examines the impact of different types of vegetation on pollutant removal efficiency, concluding that PSV-CWs are a promising and viable option for the treatment of these effluents.

Effects of saturated fatty acid consumption on lipoprotein(a): a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: An inverse relationship between saturated fatty acid (SFA) intake and Lp(a) concentration has been observed; however, there has been no quantification of this effect. OBJECTIVES: The objective was to determine if SFA consumption alters Lp(a) levels among adults without atherosclerotic cardiovascular disease (ASCVD). METHODS: A systematic review and meta-analysis of randomized controlled trials contrasting a lower SFA diet(s) with a higher SFA diet(s) among adults without ASCVD was conducted. PubMed, Cochrane Central Register of Clinical Trials, ClinicalTrials.gov, and Web of Science databases and registers were searched through October 2023. The standardized mean difference in Lp(a) between diets lower vs. higher in SFA (percent of energy [%E]) was determined using random-effects meta-analysis. Analyses were also conducted to examine the effect of replacing SFA with carbohydrates (CHO), monounsaturated (MUFA), polyunsaturated (PUFA), or trans fatty acids (TFAs). RESULTS: In total, 6,255 publications were identified in the systematic search. Twenty-six publications reporting 27 randomized controlled trials, including 1,325 participants and 49 diet comparisons, were included. The mean difference in SFA between lower vs. higher SFA diets was 7.6% E (3.7% - 17.8% E). After lower SFA diets, Lp(a) concentration was higher (SMD 0.14 [95%CI: 0.03, 0.24]) compared to higher SFA diets. Subgroup analyses showed higher Lp(a) following diets where SFA was replaced by CHO (trials=8, n=539; SMD 0.21 [95%CI: 0.02, 0.40]) or TFAs (trials=8, n=300; SMD 0.32 [95%CI: 0.17, 0.48]). No differences in Lp(a) were observed when MUFA (trials=16, n=641; SMD 0.04 [95%CI: -0.08, 0.16]) or PUFA (trials=8, n=415; SMD 0.09 [-0.04, 0.22]) replaced SFA. CONCLUSIONS: Lower SFA diets modestly increase Lp(a) compared to higher SFA diets among individuals without ASCVD. This effect appeared to be driven by replacement of SFA with CHO or TFA. Research investigating the atherogenicity of diet induced Lp(a) changes is needed to inform dietary management of lipid/lipoprotein disorders. (PROSPERO Registration number: CRD42020154169).

Steam quality monitoring as a strategy to reduce wet packs and sterilization failure.

BACKGROUND: Hospital articles processed by steam are widely used in the Central Sterile Supply Department (CSSD), responsible for cleaning, disinfection, preparation, and sterilization. Steam sterilization is discussed worldwide, aiming to protect patients, and technical norms help to standardize the entire process. If steam is outside the specified requirements, the sterilization process may fail, resulting in the wet packs at the end of the sterilization cycle. AIM AND METHOD: The present study evaluated the steam quality at Santa Catarina Hospital (São Paulo, SP, Brazil) from 2016 to 2022. Saturated steam containing non-condensable gases, excess condensate, or even superheat was characterized using the methodology indicated in the European Standard EN285:2015. RESULTS: From 2016 to 2020, qualification tests showed that the saturated steam quality does not achieve standards limit parameters for non-condensable gases and dryness values. Infrastructural maintenance actions were taken to adjust the saturated steam quality. In 2021, the steam quality followed technical standards, and its adequacy was confirmed in 2022. CONCLUSION: The points developed by the hospital's maintenance department, following the relevant technical guidelines, the adoption of appropriate devices for this purpose, and the correct preventive maintenance in the autoclaves, together with the correct qualification of the equipment and proof of the steam quality contributed to improve the safety of the hospital sterilization process and reduce the incidence of wet packages.

Assessing the impact of concurrent high-fructose and high-saturated fat diets on pediatric metabolic syndrome: A review.

High-saturated fat (HF) or high-fructose (HFr) consumption in children predispose them to metabolic syndrome (MetS). In rodent models of MetS, diets containing individually HF or HFr lead to a variable degree of MetS. Nevertheless, simultaneous intake of HF plus HFr have synergistic effects, worsening MetS outcomes. In children, the effects of HF or HFr intake usually have been addressed individually. Therefore, we have reviewed the outcomes of HF or HFr diets in children, and we compare them with the effects reported in rodents. In humans, HFr intake causes increased lipogenesis, hypertriglyceridemia, obesity and insulin resistance. On the other hand, HF diets promote low grade-inflammation, obesity, insulin resistance. Despite the deleterious effects of simultaneous HF plus HFr intake on MetS development in rodents, there is little information about the combined effects of HF plus HFr intake in children. The aim of this review is to warn about this issue, as individually addressing the effects produced by HF or HFr may underestimate the severity of the outcomes of Western diet intake in the pediatric population. We consider that this is an alarming issue that needs to be assessed, as the simultaneous intake of HF plus HFr is common on fast food menus.

Increased obesogenic action of palmitic acid during early stage of adipogenesis.

The functional differences between preadipocytes and fully differentiated mature adipocytes derived from stromal vascular fraction stem cells, as well as primary adipocytes have been analysed by evaluating their response to the obesogenic factor (a saturated fatty acid) and TNF-triggered inflammation. The analysis of single adipocytes shows that the saturated fatty acid (palmitic acid) accumulation is accompanied by inflammation and considerably dependent on the stage of the adipogenesis. In particular, preadipocytes show the exceptional potential for palmitic acid uptake resulting in their hypertrophy and the elevated cellular expression of the inflammation marker (ICAM-1). Our research provides new information on the impact of obesogenic factors on preadipocytes that is important in the light of childhood obesity prevention.

A comprehensive review: Impact of oleogel application on food texture and sensory properties.

Oleogels, characterized by their semisolid matrix formed from liquid oil structured by gelators, are emerging as a pivotal innovation in food formulation, primarily due to their capacity to enhance the nutritional profile of products by incorporating healthier fats. This review explored the integration of oleogels into diverse food matrices, examining their impact on texture, mouthfeel, and overall sensory characteristics. Through an extensive analysis of current research, this paper illustrates the versatility of oleogels created with a variety of structuring agents across different food applications. It also addresses the challenges inherent in the use of oleogels, including the preservation of their stability and consistency through varying storage and processing conditions, navigating the regulatory landscape concerning oleogelator safety and acceptability, and confronting higher production costs. Overall, this comprehensive review highlights the potential of oleogels as a promising tool for achieving desirable textural and sensory attributes in food products while also identifying areas for future research and development.

Modeling different infectious phases of hepatitis B with generalized saturated incidence: An analysis and control.

Hepatitis B is one of the global health issues caused by the hepatitis B virus (HBV), producing 1.1 million deaths yearly. The acute and chronic phases of HBV are significant because worldwide, approximately 250 million people are infected by chronic hepatitis B. The chronic stage is a long-term, persistent infection that can cause liver damage and increase the risk of liver cancer. In the case of multiple phases of infection, a generalized saturated incidence rate model is more reasonable than a simply saturated incidence because it captures the complex dynamics of the different infection phases. In contrast, a simple saturated incidence rate model assumes a fixed shape for the incidence rate curve, which may not accurately reflect the dynamics of multiple infection phases. Considering HBV and its various phases, we constructed a model to present the dynamics and control strategies using the generalized saturated incidence. First, we proved that the model is well-posed. We then found the reproduction quantity and model equilibria to discuss the time dynamics of the model and investigate the conditions for stabilities. We also examined a control mechanism by introducing various controls to the model with the aim to increase the population of those recovered and minimize the infected people. We performed numerical experiments to check the biological significance and control implementation.

Dynamical analysis of a network-based SIR model with saturated incidence rate and nonlinear recovery rate: an edge-compartmental approach.

A new network-based SIR epidemic model with saturated incidence rate and nonlinear recovery rate is proposed. We adopt an edge-compartmental approach to rewrite the system as a degree-edge-mixed model. The explicit formula of the basic reproduction number $ \mathit{\boldsymbol{R_{0}}} $ is obtained by renewal equation and Laplace transformation. We find that $ \mathit{\boldsymbol{R_{0}}} < 1 $ is not enough to ensure global asymptotic stability of the disease-free equilibrium, and when $ \mathit{\boldsymbol{R_{0}}} > 1 $, the system can exist multiple endemic equilibria. When the number of hospital beds is small enough, the system will undergo backward bifurcation at $ \mathit{\boldsymbol{R_{0}}} = 1 $. Moreover, it is proved that the stability of feasible endemic equilibrium is determined by signs of tangent slopes of the epidemic curve. Finally, the theoretical results are verified by numerical simulations. This study suggests that maintaining sufficient hospital beds is crucial for the control of infectious diseases.

Maternal fat intake in pregnancy and risk of depressive symptoms in Japanese adolescents: the Kyushu Okinawa Maternal and Child Health Study.

The current prebirth cohort study investigated the association between maternal intake of specific types of fatty acids during pregnancy and adolescent depressive symptoms based on the Center for Epidemiologic Studies Depression Scale. Subjects were 873 mother-child pairs. Dietary intake during the preceding month was assessed using a self-administered diet history questionnaire. The risk of depressive symptoms was 23.3% among the 873 adolescents at 13 years of age. Higher maternal saturated fatty acid intake during pregnancy was independently associated with a reduced risk of depressive symptoms in adolescents. Maternal intake of total fat, monounsaturated fatty acids, n-3 polyunsaturated fatty acids, α-linolenic acid, eicosapentaenoic acid, docosahexaenoic acid, n-6 polyunsaturated fatty acids, linoleic acid, arachidonic acid and cholesterol during pregnancy was not significantly related to depressive symptoms in adolescents. Higher maternal intake of saturated fatty acids during pregnancy may be inversely associated with adolescent depressive symptoms.

Energy and nutrient intake by 11-13-year-old young adolescents attending private schools in Delhi, India.

There are no high-quality data on dietary behavior of adolescents in India. This study aimed to assess the intake of energy (E), macronutrients and selected micronutrients in a sample of 11-13-year-old schoolchildren in Delhi, India. Participants from private schools (n=10) recorded dietary intake using a 3-day food diary. Information was entered into the dietary assessment tool, Intake24, to ascertain portion size and convert data into nutrient intake through integrated food tables. Of the 514 consenting participants, 393 (76.4%) (169 girls, 224 boys) aged 11.4 (± 1.8) years completed the study. The median (interquartile range (IQR) daily E intake was 2580 (2139.3-2989.8) kcal [10.8 (9.0 -12.5) MJ] for girls, and 2941.5 (2466.7- 3599.3) kcal [12.3 (10.3- 15.2) MJ] for boys. The median (IQR) daily nutrient intakes for girls and boys respectively were: protein 64.6 (54.8-79.3) g, 74.4 (61.4; 89.4) g; carbohydrate 336.5 (285.3- 393.6) g, 379.6 (317.8-461.8) g; and saturated fat 45.6 (34.8-58.3) g, 54.6 (41.9-69.5) g. There were no significant between-gender differences in percent E from protein (10.2 (9.2 - 11.4)), or carbohydrate (52.4 (48.7- 56.7)). Girls obtained less percent E from saturated fat (16.1 (11.0-18.2) compared with boys 16.3 (14.2 - 19.1) (P<0.05). E from saturated fat was above Food and Agriculture Organization recommendations in >74% participants. The EAR for iron was achieved by < 40% of girls. In conclusion, strategies to optimize dietary intake of adolescents in India should focus on preventing excess intakes of E and saturated fat, and improving iron intake in girls.

Divergent structural leaf trait spectra in succulent versus non-succulent plant taxa.

BACKGROUND AND SCOPE: Plant functional traits are the result of natural selection to optimize carbon gain, leading to a broad spectrum of traits across environmental gradients. Among plant traits, leaf water storage capacity is paramount for plant drought resistance. We explored whether leaf-succulent taxa follow similar trait correlations as non-leaf-succulent taxa to evaluate whether both are similarly constrained by relationships between leaf water storage and climate. We tested the relationships among three leaf traits related to water storage capacity and resource use strategies in 132 species comprising three primary leaf types: succulent, sclerophyllous, and leaves with rapid returns on water investment - referred to as fast return. Correlation coefficients among specific leaf area (SLA), water mass per unit of area (WMA), and saturated water content (SWC) were tested, along with relationships between leaf trait spectra and aridity determined from species occurrence records. CONCLUSION: Both SWC and WMA at a given SLA were approximately 10-fold higher in succulent leaves than in non-succulent leaves. While SWC actually increased with SLA in non-succulent leaves, no relationship was detected between SWC and SLA in succulent leaves, although WMA decreased with SLA in all leaf types. A principal component analysis revealed that succulent-taxa occupied a widely different mean trait space than either fast-return (P < 0.0001) and sclerophyllous taxa (P < 0.0001) along the first PCA axis, that explained 63% of mean trait expression among species. However, aridity only explained 12% of the variation in PCA1 values. This study is among the first to establish a structural leaf trait spectrum in succulent leaf taxa and quantify contrasts in leaf water storage among leaf types relative to specific leaf area. Results show that trait coordination in succulent leaf taxa may not follow similar patterns as widely studied non-succulent taxa.

Breakfast consumption, saturated fat intake, and body mass index among medical and non-medical students: a cross-sectional analysis.

Changes in dietary patterns and body weight have become a focus of research in undergraduate students. This study compared breakfast consumption, intake of foods high in saturated fat, and BMI between medical and non-medical students. A comparative cross-sectional study was conducted in 4,561 Peruvian university students, of whom 1,464 (32.1%) were from the medical field and 3,097 (67.9%) from the non-medical field. We compared the frequency of breakfast consumption (categorized as regular: 6 to 7 days/week; occasional: 3 to 5 days/week; and rarely or never: 0 to 2 days/week) and the frequency of consumption of foods high in saturated fat. We created simple and multiple linear and Poisson regression models with robust variance to evaluate the association of the mentioned variables with academic fields. Non-medical students (Adjusted Prevalence Ratio [PR] = 0.92, 95% CI 0.86-0.99; p = 0.008) were less likely to eat breakfast regularly compared to medical students. Likewise, consumption of foods high in saturated fats was higher in non-medical students (B = 1.47, 95% CI 0.91-2.04; p < 0.001) compared to medical students. Similarly, the mean BMI of these students was significantly higher than that of medical students (B = 0.33, 95% CI 0.12-0.53; p = 0.002). Although medical students reported relatively healthy eating habits and a lower BMI, there is a widespread need to promote improved diet and lifestyle among the entire university population to reduce the risks of communicable diseases and improve quality of life.

Examining the source and composition of organic matter through saturated hydrocarbons, δ13C, and δ15N in a subtropical water reservoir.

The sources of organic matter in the sediments of the Passaúna reservoir, an important water supply for the local population, were thoroughly investigated. The objective was to identify the origins of organic matter through the analysis of saturated hydrocarbons, elemental composition (total organic carbon and total nitrogen), and the content of δ13C and δ15N isotopes. This comprehensive approach allowed us to trace the sources of organic matter and discerns indicating heightened primary productivity within the reservoir. To achieve this, two sediment cores spanning a 140-year interval (1880-2020) were retrieved from the reservoir. Core 2 accumulates the majority of sediments, particularly near the dam area. In these parts, sediment deposits can reach up to 1 m above the pre-impoundment soil. Sediments near the area where core 1 was collected contain more sand, resulting in lower thickness compared to core 2. Sediment core 1 primarily reflects terrestrial sources of organic matter, as supported by stable isotope values of δ13C and δ15N. The δ13C values ranged from -23.0 ‰ to -25.7 ‰ in core 1 and from -28.4 ‰ to -29.2 ‰ in core 2. Meanwhile, the δ15N values ranged from 6.6 ‰ to 10.8 ‰ in core 1 and from 3.8 ‰ to 7.6 ‰ in core 2. The distribution of saturated hydrocarbons revealed that organic matter originates from both allochthonous and autochthonous sources. Periods of intense primary productivity were indicated by the presence of n-C16, n-C17, n-C18, and n-C19 alkanes. Additionally, we observed periods characterized by high primary productivity, indicative of elevated nutrient input likely resulting from increased urbanization and industrial activity in the area.

Cryo-electron tomography study of the evolution of wormlike micelles to saturated networks and perforated vesicles.

HYPOTHESIS: The formation of micellar aggregates and the changes in their morphology are crucial for numerous practical applications of surfactants. However, a proper structural characterization of complicated micellar nanostructures remains a challenge. This paper demonstrates the advances of cryo-electron tomography (cryo-ET) in revealing the structural characteristics that accompany the evolution of surfactant aggregates. EXPERIMENTS: By using cryo-ET in combination with cryo-transmission electron microscopy (cryo-TEM), small-angle neutron scattering (SANS), and rheometry, studies were carried out on a model system composed of zwitterionic and nonionic surfactants. In this system, the molecular packing parameter was increased gradually by increasing the molar fraction of nonionic surfactant. FINDINGS: A series of structural transformations was observed: linear wormlike micelles (WLMs) â†’ branched WLMs â†’ saturated network of multiconnected WLMs â†’ perforated vesicles (stomatosomes). The transformations occur through an increase in the number of branches at the expense of cylindrical subchains and semispherical endcaps. Exponential distribution of subchains length was confirmed experimentally for multiconnected saturated networks. The stomatosomes were formed when the length of subchains becomes much shorter than the persistence length, causing the three-dimensional (3D) structure to transform into a two-dimensional (2D) membrane. This work identifies the mechanism of the structural changes, which can be further used to design various surfactant self-assemblies.

Brain lipid sensing and the neural control of energy balance.

The central nervous system continuously detects circulating concentrations of lipids such as fatty acids and troglycerides. Once information has been detected, the central nervous system can in turn participate in the control of energy balance and blood sugar levels and in particular regulate the secretion and action of insulin. Neurons capable of detecting circulating lipid variations are located in the hypothalamus and in other regions such as the nucleus accumbens, the striatum or the hippocampus. An excess of lipids will have deleterious effects and may induce central lipotoxicity, in particular following local production of ceramides and the appearance of neuroinflammation which may lead to metabolic diseases such as obesity and type 2 diabetes.

Current status and emerging frontiers in enzyme engineering: An industrial perspective.

Protein engineering mechanisms can be an efficient approach to enhance the biochemical properties of various biocatalysts. Immobilization of biocatalysts and the introduction of new-to-nature chemical reactivities are also possible through the same mechanism. Discovering new protocols that enhance the catalytic active protein that possesses novelty in terms of being stable, active, and, stereoselectivity with functions could be identified as essential areas in terms of concurrent bioorganic chemistry (synergistic relationship between organic chemistry and biochemistry in the context of enzyme engineering). However, with our current level of knowledge about protein folding and its correlation with protein conformation and activities, it is almost impossible to design proteins with specific biological and physical properties. Hence, contemporary protein engineering typically involves reprogramming existing enzymes by mutagenesis to generate new phenotypes with desired properties. These processes ensure that limitations of naturally occurring enzymes are not encountered. For example, researchers have engineered cellulases and hemicellulases to withstand harsh conditions encountered during biomass pretreatment, such as high temperatures and acidic environments. By enhancing the activity and robustness of these enzymes, biofuel production becomes more economically viable and environmentally sustainable. Recent trends in enzyme engineering have enabled the development of tailored biocatalysts for pharmaceutical applications. For instance, researchers have engineered enzymes such as cytochrome P450s and amine oxidases to catalyze challenging reactions involved in drug synthesis. In addition to conventional methods, there has been an increasing application of machine learning techniques to identify patterns in data. These patterns are then used to predict protein structures, enhance enzyme solubility, stability, and function, forecast substrate specificity, and assist in rational protein design. In this review, we discussed recent trends in enzyme engineering to optimize the biochemical properties of various biocatalysts. Using examples relevant to biotechnology in engineering enzymes, we try to expatiate the significance of enzyme engineering with how these methods could be applied to optimize the biochemical properties of a naturally occurring enzyme.

Exploring bacterial community assembly in vadose and saturated zone soil for tailored bioremediation of a long-term hydrocarbon-contaminated site.

Indigenous soil microbial communities play a pivotal role in the in situ bioremediation of contaminated sites. However, research on the distribution characteristics of microbial communities at various soil depths remains limited. In particular, there is little information on the assembly of microbial communities, especially those with degradation potential, in the vadose and saturated zones of hydrocarbon-contaminated sites. In this study, 18 soil samples were collected from the vadose zone and saturated zone at a long-term hydrocarbon-contaminated site. The diversity, composition, and driving factors of assembly of the soil bacterial community were determined by high-throughput sequencing analysis. Species richness and diversity were significantly higher in the vadose zone soils than in the saturated zone soils. Significant differences in abundance at both the phylum and genus levels were observed between the two zones. Soil bacterial community assembly was driven by the combination of pollution stress and nutrients in the vadose zone but by nutrient limitations in the saturated zone. The abundance of dechlorinating bacteria was greater in the saturated zone soils than in the vadose zone soils. Compared with contaminant concentrations, nutrient levels had a more pronounced impact on the abundance of dechlorinating bacteria. In addition, the interactions among dechlorinating bacterial populations were stronger in the saturated zone soils than in the vadose zone soils. These findings underscore the importance of comprehensively understanding indigenous microbial communities, especially those with degradation potential, across different soil layers to devise specific, effective in situ bioremediation strategies for contaminated sites.

A partial siphon operational strategy strengthens nitrogen removal performance in partially saturated vertical flow constructed wetlands.

The carbon‒oxygen balance has always been problematic in constructed wetlands (CWs), putting pressure on stable and efficient nitrogen removal. In this study, a novel partial siphon operational strategy was developed to further optimize the carbon and oxygen distributions of a partially saturated vertical flow CW (SVFCW) to enhance nitrogen removal. The removal performances of the partial siphon SVFCW (S-SVFCW) were monitored and compared with those of the SVFCWs at different partial siphon depths (15 cm, 25 cm and 35 cm) in both the warm and cold seasons. The results showed that the partial siphon operating strategy significantly facilitated the removal of ammonia and total nitrogen (TN) in both the warm and cold seasons. When the partial siphon depth was 25 cm, the S-SVFCWs had the highest TN removal efficiency in both the warm (71%) and cold (56%) seasons, with an average improvement of 46% and 52%, respectively, compared with those of the SVFCWs. The oxidation‒reduction potential (ORP) results indicated that richer OPR environments and longer hydraulic detention times were obtained in the S-SVFCWs, which enriched the denitrification bacteria. Microbial analysis revealed greater nitrification and denitrification potentials in the unsaturated zone with enriched functional genes (e.g., amo_AOA, amo_AOB, nxrA and nirK), which are related to nitrification and denitrification processes. Moreover, the strengthening mechanism was the intensified oxygen supply and carbon utilization efficiency based on the cyclic nitrogen profile analysis. This study provides a novel partial siphon operational strategy for enhancing the nitrogen removal capacity of SVFCWs without additional energy or land requirements.

Molecular mechanism of saturated aldehyde oxidation: A DFT insight into volatiles forming from decanal thermal oxidation.

Decanal is one of the main products of lipid oxidation. It has been shown that decanal can oxidize to form volatiles with shorter carbon chains during heating, but the mechanism is still unclear. In this study, volatile compounds formed in the decanal thermal oxidation were verified using thermal-desorption cryo-trapping combined with GC-MS. A total of 32 volatile compounds were identified. The oxidation mechanism of decanal was studied by applying density functional theory. Results revealed that the carbonyl carbon atom was the thermal oxidation site of decanal and two pathways of peroxide oxidation were determined: the ortho­carbon and the meta­carbon oxidation. The ortho­carbon oxidation pathway is superior to the occurrence of the meta­carbon oxidation pathway. The oxidative mechanism of decanal was finally summarized as the peroxide oxidation based on radical attack on the carbonyl carbon, which would provide a theoretical basis for exploring the oxidation mechanism of other saturated aldehydes.

Substitutions of saturated fat intakes with other macronutrients and foods and risk of NAFLD cirrhosis and all-cause hepatocellular carcinoma: a prospective cohort study.

BACKGROUND: Short-term trials have shown a reduction in liver fat when saturated fatty acids (SFAs) are substituted with polyunsaturated fatty acids (PUFA), or with low-glycemic carbohydrates. However, few cohort studies have been conducted to investigate the associations of replacing SFA and SFA-rich foods with different macronutrients and foods in more severe stages of liver disease; nonalcoholic fatty liver disease (NAFLD) cirrhosis and hepatocellular carcinoma (HCC). OBJECTIVES: To investigate associations between the substitution of SFA and SFA-rich foods with other macronutrients and foods and NAFLD cirrhosis and HCC in a middle-aged to elderly Swedish population of n = 77,059 males and females. METHODS: Time-to-event analyses were performed to investigate associations between the food and macronutrient substitutions and NAFLD cirrhosis and HCC. Multivariable Cox regression models were constructed to estimate hazard ratios (HRs) with corresponding 95% confidence intervals (CIs). Statistical isocaloric and equal-mass substitutions were performed using the leave-one-out method. Prespecified nutrient and food substitutions of interest were SFA with carbohydrates, SFA with fiber, SFA with PUFA, butter with margarine and vegetable oils, unprocessed red meat with fish, and milk with fermented milk. RESULTS: Over a median follow-up of 24 y, 566 cases of NAFLD cirrhosis and 205 cases of HCC were registered. Overall, dietary substitutions showed no clear associations with either NAFLD cirrhosis or HCC. Substituting SFA with carbohydrates showed an HR of 0.87 (95% CI: 0.74, 1.02) for HCC and 1.00 (95% CI: 0.89, 1.11) for NAFLD cirrhosis. Substituting milk with fermented milk showed an HR of 0.93 (95% CI: 0.85, 1.01) for HCC and 0.97 (95% CI: 0.92, 1.03) for NAFLD cirrhosis. CONCLUSIONS: No clear associations were observed between diet and NAFLD cirrhosis or HCC. Although accompanied by low precision, possible lowered risks of HCC by substituting SFA with carbohydrates or milk with fermented milk might be of interest, but needs replication in other cohorts.