Corrosion Behavior of Homogenized and Extruded 1100 Aluminum Alloy in Acidic Salt Spray.

The 1100 aluminum alloy has been widely used in many industrial fields due to its high specific strength, fracture toughness, excellent thermal conductivity, and corrosion resistance. In this study, the corrosion behavior of the homogenized and hot-extruded 1100 aluminum alloy in acid salt spray environment for different time was studied. The microstructure of the 1100 aluminum alloy before and after corrosion was characterized by an optical microscope (OM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and a laser scanning confocal microscope (LSCM). The difference in corrosion resistance between the homogenized and extruded 1100 aluminum alloy was analyzed via the electrochemical method. The results indicate that after hot extrusion at 400 °C, the microstructure of the 1100 aluminum alloy changes from an equiaxed crystal structure with (111) preferentially distributed in a fibrous structure with (220) preferentially distributed. There was no obvious dynamic recrystallization occurring during extrusion, and the second-phase particles containing Al-Fe-Si were coarse and unevenly distributed. With the increase in corrosion time, corrosion pits appeared on the surface of the 1100 aluminum alloy, and a corrosion product layer was formed on the surface of the homogenized 1100 aluminum alloy, which reduced the corrosion rate. After 96 h of corrosion, the CPR of the extruded samples was 0.619 mm/a, and that of the homogenized samples was 0.442 mm/a. The corrosion resistance of the extruded 1100 aluminum alloy was affected by the microstructure and the second phase, and no protective layer of corrosion products was formed on the surface, resulting in a faster corrosion rate and deeper corrosion pits.

Flavonoids from citrus peel display potential synergistic effects on inhibiting rumen methanogenesis and ammoniagenesis: a microbiome perspective.

Flavonoids have been recognized as potential phytochemicals to reduce enteric methane (CH4) production and improve rumen nitrogen efficiency in ruminants. We evaluated whether naringin, hesperidin, their combination, or a mixed citrus flavonoid extract (CFE) as additives can inhibit methanogenesis and ammoniagenesis in dairy cows using an in vitro rumen batch refermentation system. The rumen inocula from dairy cows were incubated in batch cultures with five groups: no addition (CON), hesperidin (20 g/kg DM), naringin (20 g/kg DM), hesperidin + naringin (10 g/kg DM of hesperidin + 10 g/kg DM of naringin), and CFE (20 g/kg DM). The combination of naringin plus hesperidin and CFE achieved greater reductions in CH4 and ammonia production compared to either naringin or hesperidin alone. Microbiome analysis revealed that the decrease in CH4 emissions may have been caused by both the direct inhibitory impact of citrus flavonoids on Methanobrevibacter and a simultaneous decrease in protozoa Isotricha abundance. The relatively lower proportion of Entodinium in naringin plus hesperidin or CFE was responsible for the lower ammonia concentration. These results suggest that citrus flavonoids possess potential synergistic effects on mitigating ruminal CH4 emissions by cows and improving nitrogen utilization.

Diversity of fungal community and quality evaluation of Spatholobus Suberectus Dunn during the process of mildew.

Spatholobus suberectus Dunn as a traditional Chinese herbal medicine, which is susceptible to being infected by molds during storage. In order to explore the diversity characteristics of fungal community and the quality evaluation of Spatholobus suberectus Dunn during the process of mildew. The study used high-throughput sequencing technology to detect the diversity characteristics of fungal community, high-performance liquid chromatography (HPLC) and ultraviolet spectrophotometry (UV-spectrophotometry) methods to detect the content of flavonoids, and enzyme-linked immunosorbent assay (ELISA) method to detect the content of Aflatoxins B1 (AFB1). The result showed that the fungi of all samples belonged to 14 phyla, 336 genera, and the dominant fungi at the early stage of mildew was not obvious, while that at middle and late stages of mildew was Aspergillus. The species diversity of fungal community was the highest at the early stage of mildew, while the species richness of fungal community was the highest at the late stage of mildew. The content of AFB1 showed an upward trend, while the content of flavonoids showed a downward trend during the process of mildew. In brief, the diversity of fungal community decreased gradually, and the number of dominant fungi increased gradually, and the quality of Spatholobus suberectus Dunn decreased gradually during the process of mildew.

Bioconversion of citrus waste by long-term DMSO-cryopreserved rumen fluid to volatile fatty acids and biogas is feasible: A microbiome perspective.

Preserving rumen fluid as the inoculum for anaerobic digestion of food waste is necessary when access to animal donors or slaughterhouses is limited. This study aims to compare two preservation methods relative to fresh ruminal inoculum: (1) cryoprotected with 5% dimethyl sulfoxide (DMSO) and stored at -20 °C and (2) frozen at -20 °C, both for 6 months. The fermentation activity of different inoculum was evaluated by rumen-based in vitro anaerobic fermentation tests (volatile fatty acids, biomass digestibility, and gas production). Citrus pomace was used as the substrate during a 96-h fermentation. The maximum volatile fatty acids, methane production, and citrus pomace digestibility from fresh rumen fluid were not significantly different from rumen fluid preserved with DMSO. Metagenome analysis revealed a significant difference in the rumen microbial composition and functions between fresh rumen fluid and frozen inoculum without DMSO. Storage of rumen fluid using -20 °C with DMSO demonstrated the less difference compared with fresh rumen fluid in microbial alpha diversity and taxa composition. The hierarchical clustering tree of CAZymes showed that DMSO cryoprotected fluid was clustered much closer to the fresh rumen fluid, showing more similarity in CAZyme profiles than frozen rumen fluid. The abundance of functional genes associated with carbohydrate metabolism and methane metabolism did not differ between fresh rumen fluid and the DMSO-20 °C, whereas the abundance of key functional genes significantly decreased in frozen rumen fluid. These findings suggest that using rumen liquid preserved using DMSO at -20 °C for 180 days is a feasible alternative to fresh rumen fluid. This would reduce the need for laboratories to maintain animal donors and/or reduce the frequency of collecting rumen fluid from slaughterhouses.

Could natural phytochemicals be used to reduce nitrogen excretion and excreta-derived N2O emissions from ruminants?

Ruminants play a critical role in our food system by converting plant biomass that humans cannot or choose not to consume into edible high-quality food. However, ruminant excreta is a significant source of nitrous oxide (N2O), a potent greenhouse gas with a long-term global warming potential 298 times that of carbon dioxide. Natural phytochemicals or forages containing phytochemicals have shown the potential to improve the efficiency of nitrogen (N) utilization and decrease N2O emissions from the excreta of ruminants. Dietary inclusion of tannins can shift more of the excreted N to the feces, alter the urinary N composition and consequently reduce N2O emissions from excreta. Essential oils or saponins could inhibit rumen ammonia production and decrease urinary N excretion. In grazed pastures, large amounts of glucosinolates or aucubin can be introduced into pasture soils when animals consume plants rich in these compounds and then excrete them or their metabolites in the urine or feces. If inhibitory compounds are excreted in the urine, they would be directly applied to the urine patch to reduce nitrification and subsequent N2O emissions. The phytochemicals' role in sustainable ruminant production is undeniable, but much uncertainty remains. Inconsistency, transient effects, and adverse effects limit the effectiveness of these phytochemicals for reducing N losses. In this review, we will identify some current phytochemicals found in feed that have the potential to manipulate ruminant N excretion or mitigate N2O production and deliberate the challenges and opportunities associated with using phytochemicals or forages rich in phytochemicals as dietary strategies for reducing N excretion and excreta-derived N2O emissions.

Integrated multi-omics analysis reveals the positive leverage of citrus flavonoids on hindgut microbiota and host homeostasis by modulating sphingolipid metabolism in mid-lactation dairy cows consuming a high-starch diet.

BACKGROUND: Modern dairy diets have shifted from being forage-based to grain and energy dense. However, feeding high-starch diets can lead to a metabolic disturbance that is linked to dysregulation of the gastrointestinal microbiome and systemic inflammatory response. Plant flavonoids have recently attracted extensive interest due to their anti-inflammatory effects in humans and ruminants. Here, multi-omics analysis was conducted to characterize the biological function and mechanisms of citrus flavonoids in modulating the hindgut microbiome of dairy cows fed a high-starch diet. RESULTS: Citrus flavonoid extract (CFE) significantly lowered serum concentrations of lipopolysaccharide (LPS) proinflammatory cytokines (TNF-α and IL-6), acute phase proteins (LPS-binding protein and haptoglobin) in dairy cows fed a high-starch diet. Dietary CFE supplementation increased fecal butyrate production and decreased fecal LPS. In addition, dietary CFE influenced the overall hindgut microbiota's structure and composition. Notably, potentially beneficial bacteria, including Bacteroides, Bifidobacterium, Alistipes, and Akkermansia, were enriched in CFE and were found to be positively correlated with fecal metabolites and host metabolites. Fecal and serum untargeted metabolomics indicated that CFE supplementation mainly emphasized the metabolic feature "sphingolipid metabolism." Metabolites associated with the sphingolipid metabolism pathway were positively associated with increased microorganisms in dairy cows fed CFE, particularly Bacteroides. Serum lipidomics analysis showed that the total contents of ceramide and sphingomyelin were decreased by CFE addition. Some differentially abundant sphingolipid species were markedly associated with serum IL-6, TNF-α, LPS, and fecal Bacteroides. Metaproteomics revealed that dietary supplementation with CFE strongly impacted the overall fecal bacterial protein profile and function. In CFE cows, enzymes involved in carbon metabolism, sphingolipid metabolism, and valine, leucine, and isoleucine biosynthesis were upregulated. CONCLUSIONS: Our research indicates the importance of bacterial sphingolipids in maintaining hindgut symbiosis and homeostasis. Dietary supplementation with CFE can decrease systemic inflammation by maintaining hindgut microbiota homeostasis and regulating sphingolipid metabolism in dairy cows fed a high-starch diet. Video Abstract.

Nirmatrelvir/ritonavir use in patients with COVID-19 on hemodialysis: a case series.

Patients undergoing hemodialysis (HD) are particularly vulnerable to coronavirus disease 2019 (COVID-19) and are at increased risk of developing severe infection. However, given the exclusion of such patients from clinical trials, there are limited data regarding the effectiveness of the antiviral drug nirmatrelvir/ritonavir (N/R) in patients on HD. We prescribed N/R to 4 patients on HD with COVID-19 after obtaining informed consent. Their clinical symptoms were improved at approximately 3 days after N/R administration. The viral load was reduced after approximately 10 days. The main adverse effects were nausea and vomiting. Rational dosage adjustment obtained good tolerance but did not influence the efficacy. These results suggest that N/R may be a promising agent for patients on HD with COVID-19.

Siliceous Origin of the Cambrian Qiongzhusi Formation Shale in the Middle Part of the Upper Yangtze Platform: Significance of Organic Matter Enrichment.

The early Cambrian Qiongzhusi Formation shale is rich in organic matter and is a high-quality marine Source rock. However, the origin of Qiongzhusi Formation siliceous rocks is unknown, and the role of siliceous rocks in the process of organic matter enrichment or preservation is also lacking. This study combines thin section, scanning electron microscopy, SEM/EDS, major and trace element analysis, and N2 adsorption experiments to analyze and evaluate the shale of the Qiongzhusi Formation in the central region of the Sichuan Basin. The quartz types in the shale of the Qiongzhusi Formation are divided into four types, namely, bioclastic siliceous rocks, terrestrial detrital quartz, siliceous microcrystalline quartz particles, and microcrystalline quartz aggregates; at the same time, according to petrographic and geochemical parameters, the content of authigenic quartz in Qiongzhusi Formation shale decreases from top to bottom, and terrigenous detrital quartz tends to increase, and biogenic silicon accounts for the majority of authigenic quartz components; autogenous quartz has a positive impact on the pore structure of shale, providing sufficient pore space for the development of organic pores and protecting the internal pore network by forming intergranular pores as rigid frameworks. At the same time, it plays a crucial role in the enrichment and preservation of organic matter.

Multi-omics analysis reveals that the metabolite profile of raw milk is associated with dairy cows' health status.

The metabolic status of dairy cows directly influences the nutritional quality and flavor of raw milk. A comprehensive comparison of non-volatile metabolites and volatile compounds in raw milk from healthy and subclinical ketosis (SCK) cows was performed using LC-MS, GC-FID, and HS-SPME/GC-MS. SCK can significantly alter the profiles of water-soluble non-volatile metabolites, lipids, and volatile compounds of raw milk. Compared with healthy cows, milk from SCK cows had higher contents of tyrosine, leucine, isoleucine, galactose-1-phosphate, carnitine, citrate, phosphatidylethanolamine species, acetone, 2-butanone, hexanal, dimethyl disulfide and lower content of creatinine, taurine, choline, α-ketoglutaric acid, fumarate, triglyceride species, ethyl butanoate, ethyl acetate, and heptanal. The percentage of polyunsaturated fatty acids in milk was lowered in SCK cows. Our results suggest that SCK can change milk metabolite profiles, disrupt the lipid composition of milk fat globule membrane, decrease the nutritional value, and increase the volatile compounds associated with off-flavors in milk.

Citrus flavonoid extracts alter the profiling of rumen antibiotic resistance genes and virulence factors of dairy cows.

Citrus flavonoid extracts (CFE) have the potential to reduce rumen inflammation, improve ruminal function, and enhance production performance in ruminants. Our previous studies have investigated the effects of CFE on the structure and function of rumen microbiota in dairy cows. However, it remains unclear whether CFE affects the prevalence of antibiotic resistance genes (ARG) and virulence factors genes (VFG) in the rumen. Therefore, metagenomics was used to identify the rumen ARG and VFG in lactating dairy cows fed with CFE diets. The results showed that CFE significantly reduced the levels of Multidrug and Antiphagocytosis in the rumen (p < 0.05) and increased the levels of Tetracycline, Iron uptake system, and Magnesium uptake system (p < 0.05). Furthermore, the changes were found to have associations with the phylum Lentisphaerae. It was concluded that CFE could be utilized as a natural plant product to regulate virulence factors and antibiotic resistance of rumen microbiota, thereby improving rumen homeostasis and the health of dairy cows.

Feeding citrus flavonoid extracts decreases bacterial endotoxin and systemic inflammation and improves immunometabolic status by modulating hindgut microbiome and metabolome in lactating dairy cows.

The objectives of this study were to determine the effects of dietary supplementation with citrus flavonoid extracts (CFE) on milk performance, serum biochemistry parameters, fecal volatile fatty acids, fecal microbial community, and fecal metabolites in dairy cows. Eight multiparous lactating Holstein cows were used in a replicated 4 × 4 Latin square design (21-day period). Cows were fed a basal diet without addition (CON) or basal diet with added CFE at 50 (CFE50), 100 (CFE10), and 150 g/d (CFE150). Feeding CFE up to 150 g/d increased milk yield and milk lactose percentage. Supplementary CFE linearly decreased milk somatic cell count. Serum cytokines interleukin-1ß (IL-1ß), IL-2, IL-6, and tumor necrosis factor-α (TNF-α) concentrations decreased linearly as the levels of CFE increased. Cows in CFE150 had lower serum lipopolysaccharide and lipopolysaccharide binding protein compared with CON. These results indicate feeding CFE decreased systemic inflammation and endotoxin levels in dairy cows. Furthermore, feeding CFE linearly increased the concentrations of total volatile fatty acids, acetate, and butyrate in feces. The relative abundances of beneficial bacteria Bifidobacterium spp., Clostridium coccoides-Eubacterium rectale group, and Faecalibacterium prausnitzii in feces increased linearly with increasing CFE supplementation. The diversity and community structure of fecal microbiota were unaffected by CFE supplementation. However, supplementing CFE reduced the relative abundances of genera Ruminococcus_torques_group, Roseburia, and Lachnospira, but increased genera Bacteroides and Phascolarctobacterium. Metabolomics analysis showed that supplementary CFE resulted in a significant modification in the fecal metabolites profile. Compared with CON, fecal naringenin, hesperetin, hippuric acid, and sphingosine concentrations were greater in CFE150 cows, while fecal GlcCer(d18:1/20:0), Cer(d18:0/24:0), Cer(d18:0/22:0), sphinganine, and deoxycholic acid concentrations were less in CFE150 cows. Predicted pathway analysis suggested that "sphingolipid metabolism" was significantly enriched. Overall, these results indicate that citrus flavonoids could exert health-promoting effects by modulating hindgut microbiome and metabolism in lactating cows.

Characterization of the Dynamic Changes of Ruminal Microbiota Colonizing Citrus Pomace Waste during Rumen Incubation for Volatile Fatty Acid Production.

Rumen microorganisms are promising for efficient bioconversion of lignocellulosic wastes to biofuels and industrially relevant products. Investigating the dynamic changes of the rumen microbial community colonizing citrus pomace (CtP) will advance our understanding of the utilization of citrus processing waste by rumen fluid. Citrus pomace in nylon bags was incubated in the rumen of three ruminally cannulated Holstein cows for 1, 2, 4, 8, 12, 24, and 48 h. Results showed that total volatile fatty acids concentrations and proportions of valerate and isovalerate were increased over time during the first 12 h. Three major cellulose enzymes attached to CtP rose initially and then decreased during the 48-h incubation. Primary colonization happened during the initial hours of CtP incubation, and microbes compete to attach CtP for degrading easily digestible components and/or utilizing the waste. The 16S rRNA gene sequencing data revealed the diversity and structure of microbiota adhered to CtP were distinctly different at each time point. The increased abundance of Fibrobacterota, Rikenellaceae_RC9_gut_group, and Butyrivibrio may explain the elevated volatile fatty acids concentrations. This study highlighted key metabolically active microbial taxa colonizing citrus pomace in a 48-h in situ rumen incubation, which could have implications for promoting the biotechnological process of CtP. IMPORTANCE As a natural fermentation system, the rumen ecosystem of ruminants can efficiently degrade plant cellulose, indicating that the rumen microbiome offers an opportunity for anaerobic digestion to utilize biomass wastes containing cellulose. Knowledge of the response of the in situ microbial community to citrus pomace during anaerobic fermentation will help improve the current understanding of citrus biomass waste utilization. Our results demonstrated that a highly diverse rumen bacterial community colonized citrus pomace rapidly and continuously changed during a 48-h incubation period. These findings may provide a deep understanding of constructing, manipulating, and enriching rumen microorganisms to improve the anaerobic fermentation efficiency of citrus pomace.

Changing Hydrocarbon-Producing Potential of the Cambrian Niutitang Shale: Insights from Pyrite Morphology and Geochemical Characteristics.

The characteristics of shale gas enrichment conditions at different depositional positions of organic-rich shale in the Niutitang Formation of the Lower Cambrian of the Upper Yangtze in South China vary greatly. The study of pyrite provides a basis for the restoration of the ancient environment and a reference for the prediction of organic-rich shale. In this paper, the organic-rich shale of the Cambrian Niutitang Formation in the Cengong area is analyzed by means of the optical microscope, scanning electron microscope observation, carbon and sulfur analysis, X-ray diffraction whole rock mineral analysis, sulfur isotope test, and image analysis. The morphology and distribution characteristics, genetic mechanism, water column sedimentary environment, and influence of pyrite on the preservation conditions of organic matter are discussed. This study shows that the upper, middle, and lower sections of the Niutitang Formation are rich in pyrite (framboid, euhedral pyrite, subhedral pyrite, etc.). Meanwhile, the sulfur isotopic composition of pyrite (δ34Spy) shows a tight correlation with the framboid size distribution throughout the shale deposits of the Niutang Formation, and the average particle size (9.6 µm; 6.8 µm; 5.3 µm) and distribution range of framboids (2.7-28.1 µm; 2.9-15.8 µm; 1.5-13.7 µm) in the upper, middle, and lower sections show a downward trend. In contrast, the sulfur isotopic composition of pyrite shows a tendency to become heavier from above and below (mean = 0.25‰ to 5.64‰). Together with the covariant mode of pyrite trace elements (such as Mo, U, V, Co, Ni, etc.), the results showed significant differences in the oxygen levels in the water column. They show that the transgression led to long-term anoxic sulfide conditions in the lower water column of the Niutitang Formation. In addition, the main and trace elements in pyrite jointly indicated that there was hydrothermal action at the bottom of the Niutitang Formation, which led to the destruction of the preservation environment of organic matter and the decrease of TOC, which can also explain the reason why the TOC content in the middle part (6.59%) was higher than that in the lower part (4.29%). Finally, the water column became an oxic-dysoxic condition due to the decline of sea level, and the TOC content decreased (1.79%).

Dietary citrus flavonoid extract improves lactational performance through modulating rumen microbiome and metabolites in dairy cows.

The effects of dietary supplementation with citrus flavonoid extract (CFE) on milk performance, rumen fermentation, rumen microbiome, rumen metabolome, and serum antioxidant indexes were evaluated. Eight multiparous lactating cows were allocated to a replicated 4 × 4 Latin square with 25-d periods consisting of 20 d of adaptation and 5 d of sampling. Experimental treatments included a control diet (CON) and CON supplemented with 50 g d-1 (CFE50), 100 g d-1 (CFE100), and 150 g d-1 (CFE150). Feeding CFE to dairy cows increased milk production and milk lactose. Milk somatic cell count linearly reduced with increasing CFE amount. Supplementing CFE linearly increased the ruminal concentrations of total volatile fatty acids, acetate, propionate, butyrate, and microbial crude protein. Ruminal lipopolysaccharide linearly decreased with increasing CFE amount. Compared with CON, CFE150 cows exhibited a greater abundance of Firmicutes and a low abundance of Bacteroidetes. Cellulolytic bacteria (genera Ruminococcus, Clostridium, and Butyrivibrio) and carbohydrate metabolism were enriched in the CFE150 cows. For archaea and viruses, major methanogens (genera Methanobacterium and Methanosarcina) and phylum Uroviricota were inhibited in the CFE150 cows. Compared with CON, the ruminal concentrations of tyrosine, proline, pyruvate, glucose, and glucose-6-phosphate were higher in the CFE150 cows. The metabolites of citrus flavonoids, such as hippuric acid, hesperetin, and naringenin, were increased in the CFE150 cows. Supplementing CFE significantly improved the antioxidant capacity of the dairy cows. This study highlighted that dietary supplementation with CFE led to significant changes in the rumen microbial composition and metabolites, and consequently resulted in an improved lactational performance of dairy cows.

Ceramide on the road to insulin resistance and immunometabolic disorders in transition dairy cows: driver or passenger?

Dairy cows must undergo profound metabolic and endocrine adaptations during their transition period to meet the nutrient requirements of the developing fetus, parturition, and the onset of lactation. Insulin resistance in extrahepatic tissues is a critical component of homeorhetic adaptations in periparturient dairy cows. However, due to increased energy demands at calving that are not followed by a concomitant increase in dry matter intake, body stores are mobilized, and the risk of metabolic disorders dramatically increases. Sphingolipid ceramides involved in multiple vital biological processes, such as proliferation, differentiation, apoptosis, and inflammation. Three typical pathways generate ceramide, and many factors contribute to its production as part of the cell's stress response. Based on lipidomic profiling, there has generally been an association between increased ceramide content and various disease outcomes in rodents. Emerging evidence shows that ceramides might play crucial roles in the adaptive metabolic alterations accompanying the initiation of lactation in dairy cows. A series of studies also revealed a negative association between circulating ceramides and systemic insulin sensitivity in dairy cows experiencing severe negative energy balance. Whether ceramide acts as a driver or passenger in the metabolic stress of periparturient dairy cows is an unknown but exciting topic. In the present review, we discuss the potential roles of ceramides in various metabolic dysfunctions and the impacts of their perturbations. We also discuss how this novel class of bioactive sphingolipids has drawn interest in extrahepatic tissue insulin resistance and immunometabolic disorders in transition dairy cows. We also discuss the possible use of ceramide as a new biomarker for predicting metabolic diseases in cows and highlight the remaining problems.

Microbiome-Metabolomics Insights into the Milk of Lactating Dairy Cows to Reveal the Health-Promoting Effects of Dietary Citrus Peel Extracts on the Mammary Metabolism.

The effects of dietary supplementation with citrus peel extract (CPE) on milk biochemical parameters, milk bacterial community, and milk metabolites were evaluated. Eight lactating cows were allocated to a replicated 4 × 4 Latin square. Experimental treatments included the control diet (CON), and CON supplemented with CPE at 50 g/d (CPE50), 100 g/d (CPE100), and 150 g/d (CPE150). Supplementing with CPE linearly decreased milk interleukin-6 and malondialdehyde concentrations and linearly increased lysozyme activity and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. Compared with CON, the milk of CPE150 cows had fewer abundances of several opportunistic pathogens and psychrotrophic bacteria, such as Escherichia-Shigella, Sphingobacterium, Alcaligenes, Stenotrophomonas, and Ochrobactrum. Supplementing with CPE significantly altered the metabolic profiling in the milk. The metabolites of flavonoids were enriched in the milk of cows fed CPE150, while some proinflammation compounds were decreased compared with CON. Correlation analysis showed that the change in the bacterial community might partly contribute to the alteration in the expression of milk cytokines. In conclusion, CPE exerts health-promoting effects (e.g., antioxidant, anti-microbial, and anti-inflammatory) in the mammary metabolism of cows due to its flavonoid compounds, which also provide additional value in terms of milk quality improvement.

Lipidomic profiling using GC and LC-MS/MS revealed the improved milk quality and lipid composition in dairy cows supplemented with citrus peel extract.

Eight lactating cows were used to determine the effects of citrus peel extract (CPE) on milk performance, antioxidant properties, and milk lipids composition. CPE supplementation up to 150 g/d (CPE150) increased milk yield and the proportions of unsaturated fatty acids of conjugated linoleic acid. CPE with abundant polyphenol and flavonoids can transfer these bioactive substances to mammary gland and improve the antioxidant properties of milk obtained from cows. Lipidomics revealed that 56 lipid species were altered between CON vs CPE150, and there were five key differential metabolic pathways. In particular, milk phosphatidylethanolamine and phosphatidylcholine were significantly increased with dietary CPE supplementation. In summary, our results provide insights into the modifications in the milk components and milk quality of dairy cows received CPE. The inclusion of CPE in the diet of dairy cows may be an effective and natural way to increase the antioxidant amounts and beneficial lipids in milk.

Matrine attenuates bovine mammary epithelial cells inflammatory responses induced by Streptococcus agalactiae through inhibiting NF-κB and MAPK signaling pathways.

Streptococcus agalactiae is one of the main pathogens associated with bovine mastitis. The invasion of S. agalactiae in bovine mammary epithelial cells (BMECs) has been implicated as a key event in the pathogenesis of mastitis. Matrine is known for its various pharmacological activities, such as immune response regulation and anti-inflammation. The primary aim of the research was to investigate the preventive effect of matrine on S. agalactiae-induced inflammation in BMECs along with underlying molecular mechanisms. Our data showed matrine at the concentrations of 50-100 µg/mL promoted BMECs proliferation without infection, and decreased cytotoxicity induced by S. agalactiae. Subsequently, BMECs were pre-treated with matrine (50, 75, or 100 µg/mL) for 24 h, followed by the infection with S. agalactiae for an additional 6 h. Pretreatment with matrine followed by S. agalactiae treatment decreased cell apoptosis of BMECs. Also, pretreatment of matrine to BMECs prevented the invasion of S. agalactiae. The mRNA abundances of IL-1ß, IL-6, IL-8, and TNF-α were down-regulated in S. agalactiae-infected cells pretreated with matrine. In addition, the greater ratios of protein NF-κB p-p65/p65, p-IκBα/IκBα, p-38/38, and p-ERK/ERK induced by S. agalactiae were attenuated due to matrine treatment. Furthermore, pretreatment of BMECs with matrine impeded the degradation of TAK1 induced by S. agalactiae infection. These results suggest matrine could be a potential modulator in immune response of the mammary gland. In conclusion, matrine prevents cellular damage due to S. agalactiae infection by the modulation of NF-κB and MAPK signaling pathways and pro-inflammatory cytokine production.

Decreasing ruminal methane production through enhancing the sulfate reduction pathway.

Methane (CH4) production from ruminants accounts for 16% of the global greenhouse gas emissions and represents 2% to 12% of feed energy. Mitigating CH4 production from ruminants is of great importance for sustainable development of the ruminant industry. H2 is the primary substrate for CH4 production in the processes of ruminal methanogenesis. Sulfate reducing bacteria are able to compete with methanogens for H2 in the rumen, and consequently inhibit the methanogenesis. Enhancing the ruminal sulfate reducing pathway is an important approach to mitigate CH4 emissions in ruminants. The review summarized the effects of sulfate and elemental S on ruminal methanogenesis, and clarified the related mechanisms through the impacts of sulfate and elemental S on major ruminal sulfate reducing bacteria. Enhancing the activities of the major ruminal sulfate reducing bacteria including Desulfovibrio, Desulfohalobium and Sulfolobus through dietary sulfate addition, elemental S and dried distillers grains with solubles can effectively decrease the ruminal CH4 emissions. Suitable levels of dietary addition with different S sources for reducing the ruminal CH4 production, as well as maintaining the performance and health of ruminants, need to be investigated in the future.

Efficacy and safety of expanded hemodialysis in hemodialysis patients: a meta-analysis and systematic review.

BACKGROUND: Expanded hemodialysis (HDx) is a new dialysis modality, but a systematic review of the clinical effects of using HDx is lacking. This systematic review and meta-analysis aimed to assess the efficacy and safety of HDx for hemodialysis (HD) patients. METHODS: PubMed, the Cochrane library, and EMBASE databases were systematically searched for prospective interventional studies comparing the efficacy and safety of HDx with those of high flux HD or HDF in HD patients. RESULTS: Eighteen trials including a total of 853 HD patients were enrolled. HDx increased the reduction ratio (RR) of ß2-microglobulin (SMD 6.28%, 95% CI 0.83, 1.73, p = .02), κFLC (SMD 15.86%, 95% CI 6.96, 24.76, p = .0005), and λFLC (SMD 22.42%, 95% CI, 17.95, 26.88, p < .0001) compared with high flux HD. The RR of ß2-microglobulin in the HDx group was lower than that in the HDF group (SMD -3.53%, 95% CI -1.16, -1.9, p < .0001). HDx increased the RRs of κFLC (SMD 1.34%, 95% CI 0.52, 2.16, p = .001) and λFLC (SMD 7.28%, 95% CI 1.08, 13.48, p = .02) compared to HDF. There was no significant difference in albumin loss into the dialysate between the HDx and HDF groups (SMD 0.35 g/session, 95% CI -2.38, 3.09, p = .8). CONCLUSIONS: This meta-analysis indicated that compared with high-flux HD and HDF, HDx can increase the clearance of medium and large-molecular-weight uremic toxins. And it does not increase the loss of albumin compared with HDF.