Reclaimed water (RW), as a reliable and renewable secondary water source, has become a crucial strategy for many countries to supplement agricultural water usage and alleviate water scarcity. However, despite the increasing use of RW, there has been limited research on the factors affecting soil nitrous oxide (N2O) emissions under RW irrigation. Understanding these factors is essential for guiding RW irrigation practices and controlling greenhouse gas emissions. This research, conducted from 2014 to 2015, includes field experiments designed to systematically assess the effects of soil chemistry properties and temperature on soil N2O emissions under RW irrigation. Subsequent to these field studies, soil samples were collected for 15N isotope trials to examine the impact of RW on the soil N2O production process, including autotrophic nitrification, heterotrophic nitrification, and denitrification. The results showed that RW irrigation influenced soil N2O emissions by affecting soil pH, but not through changes in soil total nitrogen (TN) or soil organic carbon (SOC) content. Moreover, compared to groundwater (UW) irrigation, RW irrigation significantly reduced the temperature sensitivity of soil N2O emissions. The 15N isotope labeling trial indicated that autotrophic nitrification was the primary pathway for soil N2O production under RW irrigation, contributing 60.46%—significantly higher than that observed with UW irrigation. Primary treated sewage (PW) significantly increased soil N2O emissions through the heterotrophic nitrification process compared to RW, with contributions rising from 11.31% to 13.23%. Additionally, RW, compared to UW, significantly increased the copy numbers of soil nitrification genes (ammonia-oxidizing archaea [AOA-amoA]) and denitrification genes (nitrite reductase [nirK and nirS]). Therefore, it is important to appropriately control the nitrification process and balance soil pH to manage soil N2O emissions under RW irrigation.
Gut bacteria employ quorum sensing (QS) to coordinate their activities and communicate with one another, this process relies on the production, detection, and response to autoinducers, which are extracellular signaling molecules. In addition to synchronizing behavioral activities within the species, QS plays a crucial role in the gut host-microbiota interaction. In this review, an overview of classical QS systems is presented as well as the interspecies communication mediated by QS, and recent advances in the host-microbiota interaction mediated by QS. A greater knowledge of the communication network of gut microbiota is not only an opportunity and a challenge for developing nutritional and therapeutic strategies against bacterial illnesses, but also a means for improving gut health.
Determination of relative root-zone water depletion (RRWD) thresholds to trigger irrigation is crucial to create optimal irrigation schedules targeting maximum yield and/or water productivity with limited water supply for a crop. In this study, a numerical procedure to determine RRWD thresholds was developed through coupling AquaCrop software with genetic-simplex algorithms. Using a two-year field lysimetric experiment for winter wheat conducted in the North China Plain (NCP), AquaCrop adequately simulated canopy cover, final aboveground biomass, grain yield, seasonal evapotranspiration, and soil water storage, with the normalized root mean squared error (NRMSE) smaller than 15 % and determination coefficient (R2) larger than 0.84. The global optimum range of RRWD thresholds was preliminarily determined using the genetic algorithm, and subsequently final RRWD thresholds were optimized by fine tuning using the simplex algorithm. The RRWD threshold combinations (composed of the RRWD thresholds to trigger different sequential irrigation events) for varying number of irrigation events (i.e.1–4) were optimized based on 39 years of historical meteorological data, and the effects of climate change on the optimal crop yield (Ya, opt), water productivity (WPopt), and the combinations of optimized RRWD threshold (RRWDopt) were investigated. The results indicated that both Ya, opt and WPopt generally increased with time showing a tendency of gradually elevated annual CO2 concentration and seasonal average effective temperature. Irrespective of the number of irrigation events during the winter wheat growing season, the differences of RRWDopt for different combinations of irrigation sequence and event in the same kind of hydrological year were relatively small, with a coefficient of variation consistently less than 23 % and a mean of 8 %. When combinations of mean RRWDopt were applied into AquaCrop to trigger irrigation for winter wheat in various hydrological years, the simulated yield (Ya, sim) and water productivity (WPsim) under 1–4 irrigation events were found to be comparable to their respective optimums (Ya, opt and WPopt), with all the values of Ya, sim (WPsim) falling in the range of 92 %Ya, opt (90 %WPopt). Therefore, the mean RRWDopt should be helpful to formulate rational irrigation management strategies of winter wheat under changing climatic conditions in the NCP.
Intestinal stem cells (ISCs), which locate at the base of intestinal crypts, are key determinants of governing proliferation and differentiation of the intestinal epithelium. The surrounding cells of ISCs and their related growth factors form ISC niche, supporting ISC function and self-renewal. ISC has an underappreciated but emerging role as a sensor of dietary nutrients, which fate decisions is adjusted in response to nutritional states to regulate gut homeostasis. Here, we review endogenous and exogenous factors, such as caloric restriction, fasting, fat, glucose and trace element. They instruct ISCs via mTORC1, PPAR/CPT1α, PPARγ/β-catenin, Wnt/GSK-3β pathway, respectively, jointly affect intestinal homeostasis. These dietary responses regulate ISC regenerative capacity and may be a potential target for cancer prevention. However, without precise definitions of nutrition intervene, it will be difficult to generate sufficient data to extending our knowledge of the biological response of ISC on nutrients. More accurately modeling organoids or high-throughput automated organoid culture in microcavity arrays have provided unprecedented opportunities for modeling diet-host interactions. These major advances collectively provide new insights into nutritional regulation of ISC proliferation and differentiation and drive us ever closer to breakthroughs for regenerative medicine and disease treatment by nutrition intervention in the clinic.
Intestinal epithelium undergoes rapid cellular turnover, relying on the local niche, to support intestinal stem cells (ISCs) function and self-renewal. Research into the association between ISCs and disease continues to expand at a rapid rate. However, the detailed interaction of ISCs and gut microbes remains to be elucidated. Thus, this review witnessed major advances in the crosstalk between ISCs and gut microbes, delivering key insights into (1) construction of ISC niche and molecular mechanism of how to jointly govern epithelial homeostasis and protect against intestinal diseases with the participation of Wnt, bone morphogenetic protein, and Notch; (2) differentiation fate of ISCs affect the gut microbiota. Meanwhile, the presence of intestinal microbes also regulates ISC function; (3) microbiota regulation on ISCs by Wnt and Notch signals through pattern recognition receptors; (4) how do specific microbiota-related postbiotics influence ISCs to maintain intestinal epithelial regeneration and homeostasis that provide insights into a promising alternative therapeutic method for intestinal diseases. Considering the detailed interaction is still unclear, it is necessary to further explore the regulatory role of gut microbiota on ISCs to utilize microbes to alleviate gut disorders. Furthermore, these major advances collectively drive us ever closer to breakthroughs in regenerative medicine and cancer treatment by microbial transplantation in the clinic.
Weaned piglets stayed in transitional stages of internal organ development and external environment change. The dual stresses commonly caused intestinal disorders followed by damaged growth performance and severe diarrhea. High dose of zinc oxide could improve production efficiency and alleviate disease status whereas caused serious environmental pollution. This research investigated if coated ZnO (C_ZnO) in low dose could replace the traditional dose of ZnO to improve the growth performance, intestinal function, and gut microbiota structures in the weaned piglets. A total of 126 cross-bred piglets (7.0 ± 0.5 kg body weight) were randomly allocated into three groups and fed a basal diet or a basal diet supplemented with ZnO (2,000 mg Zn/kg) or C_ZnO (500 mg Zn/kg), respectively. The test lasted for 6 weeks. C_ZnO improved average daily gain (ADG) and feed efficiency, alleviated diarrhea, decreased the lactulose/mannitol ratio (L/M) in the urine, increased the ileal villus height, and upregulated the expression of Occludin in the ileal tissue and the effect was even better than a high concentration of ZnO. Importantly, C_ZnO also regulated the intestinal flora, enriching Streptococcus and Lactobacillus and removing Bacillus and intestinal disease-associated pathogens, including Clostridium_sensu_stricto_1 and Cronobacter in the ileal lumen. Although, colonic microbiota remained relatively stable, the marked rise of Blautia, a potential probiotic related to body health, could still be found. In addition, C_ZnO also led to a significant increase of acetate and propionate in both foregut and hindgut. Collectively, a low concentration of C_ZnO could effectively promote growth performance and reduce diarrhea through improving small intestinal morphology and permeability, enhancing the barrier function, adjusting the structure of gut microbiota, and raising the concentration of short-chain fatty acids (SCFAs) in the weaned piglets.
Maintainance of sulfomucin is a key end point in the treatment of diarrhea and inflammatory bowel disease (IBD). However, the mechanisms underlying the microbial sense to sulfomucin are poorly understood, and to date, there are no therapies targeting the secretion and maturation of sulfomucin in IBD. Herein, we biosynthesized poly-β-hydroxybutyrate (PHB) and found that PHB could alleviate inflammation caused by diarrhea and colitis by enhancing the differentiation of sulfomucin. Microbiota transplantation and clearance together demonstrate that PHB promoting sulfomucin is mediated by Lactobacillus johnsonii ( L. johnsonii ). Further studies revealed that PHB provides a favorable niche for L. johnsonii biofilm formation to resist disturbance and support its growth. L. johnsonii -biofilm alleviates colitis by regulating fucose residues to promote goblet cell differentiation and subsequent sulfomucin maturation. Importantly, PHB alleviates colitis by enhancing sulfomucin secretion and maturation in a L. johnsonii -dependent manner. PHB represents a class of guardians, acting as a safe probiotic-biofilm delivery system that significantly promotes probiotic proliferation. Altogether, this study adds weight to the possible role of probiotics and functional materials in the treatment of intestinal inflammation. The application of PHB and biofilm self-coating L. johnsonii carries high translational potential and may be of clinical relevance.
Based on the characteristic of low diarrhea in native Chinese breeds, we introduce the enterotype model for piglets, which is a new perspective to decipher the colonization and the transition of the gut microbiota among various pig breeds. After eliminating environmental influences represented by diet, the microbiota, mainly shaped by host genetics, is focused. Three representative enterotype clusters were identified, which were represented by Bacteroides, Streptococcus, and Lactobacillus. Chinese native breeds were distributed in enterotype 1 (E1) and E3, which collectively drove the diversification and functionality of the microbial community of various Chinese pig breeds. Next, the Lactobacillus reuteri (L. reuteri), which is the representative strain of E3, was specifically isolated in all three enterotypes. The excellent stress-resistance of L. reuteri-E3 not only highlighted the stronger disease resistance of Chinese breeds but also had a great potential to intervene in weaned piglet diseases. Enterotype classification based on host genetics is much more deterministic and predictable, clarifying the driver of the host-microbiome dynamics and constructing the picture of the micro-coevolution of human host genetics with the gut microbiome.
Reclaimed water is an alternative water source which could alleviate the shortage of water resources in agricultural systems. Many researchers have studied the effect of reclaimed water on soil environment, crop yield, etc. However, carbon sequestration in reclaimed water irrigated agricultural systems is less studied. This study investigates methane uptake and photosynthesis in reclaimed water irrigation systems contributing to carbon sequestration estimation and analyzes the important factors impacting them. The results show that CH4 uptake is related to soil water-filled pore space (WFPS) with a quadratic and it has the highest uptake when WFPS is between 40 and 50%. Long-term reclaimed water irrigation could significantly decrease (p < 0.05) CH4 uptake and macroaggregate stability in the topsoil. However, reclaimed water had no significant impact on photosynthesis in comparison. The type of fertilizer is an important factor which impacts CH4 emission from soil; urea had a lower CH4 uptake and a higher CO2 emission than slow-released fertilizer. Overall, reclaimed water irrigation could effectively decrease soil carbon sequestration. A soil wetted proportion level of 40–50% was recommended in this study for favorable methane oxidation. Slow-released fertilizer in reclaimed water irrigated agriculture could better control soil carbon emission and soil carbon absorption.
Background: Iliopsoas bursal cystic lesion (IBCL), a rare disease on groin area, posing a significant threat to the lower limb thrombosis, but it is easy to misdiagnose or missed diagnose. Doppler ultrasonography (DU) with certain advantages could be used to detect the enlarged iliopsoas bursa (EIB) and compression of lower extremity vein. Case presentation: A 60-year-old man was admitted to our department complaining of pain and swelling in his right groin area for 3 weeks. DU demonstrated that there was a well-defined, echo-free, cystic mass in the right inguinal region, which severely compressed the common femoral vein (CFV), and the blood flow velocity was extremely slow. Then, surgery was performed to exclude the lesion, consequently, corresponding signs and symptoms had resolved completely. Histopathological results suggested the mass is an iliopsoas bursa filled with mucinous materials. After that, DU was displayed again and the results suggested that the EIB has almost been excised and there was a slight echogenic structure in the deep layer communicating to the hip joint space. Conclusion: Although, IBCL is rare and easy to misdiagnose and missed diagnose, the DU with certain advantages could be used to diagnose effectively this disease and guide the clinical prevention and intervention of thromboembolic events.
The intestinal homeostasis is an orchestrated dynamic equilibrium state composed of the coexistence and interactions among the nutrients, microbial flora, and immune system. The intestinal balance disorder can trigger a series of diseases, such as inflammatory bowel disease (IBD). Many of tryptophan (Trp) metabolites, such as kynurenine and indole, generated under a series of endogenous enzymes or microbial metabolism, have been reported enable to bind and activate the aryl hydrocarbon receptor (AhR), this series of process is termed the Trp-AhR pathway. The activated Trp-AhR pathway can induce the expression of downstream cytokines such as interleukin-22 (IL-22) and interleukin-17 (IL-17), thereby regulating the intestinal homeostasis. This review highlights the advance of Trp-AhR pathway in the regulation of intestinal homeostasis and provides some insights for the clinical strategies that expect to effectively prevent and treat gut diseases via intervening the Trp-AhR pathway.
Over the last 27 years (1990-2017), based on the revolutionary progresses of basic nutrition research, novel methods and techniques have been developed which bring a profound technological revolution to pig production from free-range system to intensive farming all over the world. Basic theoretical innovations and feed production studies have provided vital advancements in pig nutrition by developing formula feed, utilizing balanced diets, determining feed energy value, dividing pig physiological stages, enhancing gut health, and improving feed processing technique. Formula feed is the primary contributor of the rise of the mechanized farming industry, and meets comprehensive nutritional needs of the pig. The focuses of the development of a balanced diet by optimizing nutrient levels are the amino acids balance, the balance between amino acids and energy, the balance between calcium and phosphorus. Multiple-site-production and targeted feeding program have been applied extensively. Early weaning of piglets improves production efficiency, but piglets that have not yet fully developed their intestine are prone to diarrhea. Therefore, intestinal health has received special attention in recent years. Feed processing technologies, such as granulation, puffing, fermentation and enzymatic hydrolysis, can improve the utilization of feed nutrients and reduce production cost. However, increasing a sow's potential for production, seeking alternatives to antibiotics, reducing drug treatment in piglets, developing functional additives and improving meat quality remain future challenges. Herein, we outline the important progresses of pig nutrition in the past 27 years, which will shed light on the basic nutrition rules of pig production, and help to push forward its future development. © 2018 Society of Chemical Industry.
In a complex, diverse intestinal environment, commensal microbiota metabolizes excessive dietary tryptophan to produce more bioactive metabolites connecting with kinds of diverse process, such as host physiological defense, homeostasis, excessive immune activation and the progression and outcome of different diseases, such as inflammatory bowel disease, irritable bowel syndrome and others. Although commensal microbiota includes bacteria, fungi, and protozoa and all that, they often have the similar metabolites in tryptophan metabolism process via same or different pathways. These metabolites can work as signal to activate the innate immunity of intestinal mucosa and induce the rapid inflammation response. They are critical in reconstruction of lumen homeostasis as well. This review aims to seek the potential function and mechanism of microbiota-derived tryptophan metabolites as targets to regulate and shape intestinal immune function, which mainly focused on two aspects. First, analyze the character of tryptophan metabolism in bacteria, fungi, and protozoa, and assess the functions of their metabolites (including indole and eight other derivatives, serotonin (5-HT) and d-tryptophan) on regulating the integrity of intestinal epithelium and the immunity of the intestinal mucosa. Second, focus on the mediator and pathway for their recognition, transfer and crosstalk between microbiota-derived tryptophan metabolites and intestinal mucosal immunity. Disruption of intestinal homeostasis has been described in different intestinal inflammatory diseases, available data suggest the remarkable potential of tryptophan-derived aryl hydrocarbon receptor agonists, indole derivatives on lumen equilibrium. These metabolites as preventive and therapeutic interventions have potential to promote proinflammatory or anti-inflammatory responses of the gut.
Nowadays, melatonin, previously considered only as a pharmaceutical product for rhythm regulation and sleep aiding, has shown its potential as a co-adjuvant treatment in intestinal diseases, however, its mechanism is still not very clear. A firm connection between melatonin at a physiologically relevant concentration and the gut microbiota and inflammation has recently established. Herein, we summarize their crosstalk and focus on four novelties. First, how melatonin is synthesized and degraded in the gut and exerts potentially diverse phenotypic effects through its diverse metabolites. Second, how melatonin mediates the activation and proliferation of intestinal mucosal immune cells with paracrine and autocrine properties. By modulating T/B cells, mast cells, macrophages and dendritic cells, melatonin immunomodulatory involved in regulating T-cell differentiation, intervening T/B cell interaction and attenuating the production of pro-inflammatory factors, achieving its antioxidant action via specific receptors. Third, how melatonin exerts antimicrobial action and modulates microbial components, such as lipopolysaccharide, amyloid-beta peptides via nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappa B) or signal transducers and activators of transcription (STAT1) pathway to modulate intestinal immune function in immune-pineal axis. The last, how melatonin mediates the effect of intestinal bacterial activity signals on the body rhythm system through the NF-kappa B pathway and influences the mucosal epithelium oscillation via clock gene expression. These processes are achieved at mitochondrial and nuclear levels to control the host immune cell development. Considering unclear mechanisms and undiscovered actions of melatonin in gut-microbiome-immune axis, it's time to reveal them and provide new insight for the outlook of melatonin as a potential therapeutic target in the treatment and management of intestinal diseases.
The intestinal tract is the shared locus of intestinal epithelial cells, immune cells, nutrient digestion and absorption, and microbial survival. The gut in animals faces continuous challenges in communicating with the external environment. Threats from endogenous imbalance and exogenous feeds, especially pathogens, could trigger a disorder of homeostasis, leading to intestinal disease and even systematic disease risk. As a part of the intestinal protective barrier, endogenous host defense peptides (HDPs) play multiple beneficial physiological roles in the gut mucosa. Moreover, enhancing endogenous HDPs is being developed as a new strategy for resisting pathogens and commensal microbes, and to maintain intestinal health and reduce antibiotic use. In recent years, multiple nutrients such as branched-chain amino acids, SCFAs, lactose, zinc, and cholecalciferol (vitamin D3) have been reported to significantly increase HDP expression. Nutritional intervention has received more attention and is viewed as a promising means to defend against pathogenic infections and intestinal inflammation. The present review focuses on current discoveries surrounding HDP expression and nutritional regulation of mechanisms in the gut. Our aim is to provide a comprehensive overview, referable tactics, and novel opinions.
Tryptophan (Trp) is not only a nutrient enhancer but also has systemic effects. Trp metabolites signaling through the well-known aryl hydrocarbon receptor (AhR) constitute the interface of microbiome-gut-brain axis. However, the pathway through which Trp metabolites affect central nervous system (CNS) function have not been fully elucidated. AhR participates in a broad variety of physiological and pathological processes that also highly relevant to intestinal homeostasis and CNS diseases. Via the AhR-dependent mechanism, Trp metabolites connect bidirectional signaling between the gut microbiome and the brain, mediated via immune, metabolic, and neural (vagal) signaling mechanisms, with downstream effects on behavior and CNS function. These findings shed light on the complex Trp regulation of microbiome-gut-brain axis and add another facet to our understanding that dietary Trp is expected to be a promising noninvasive approach for alleviating systemic diseases.
The use of fertilizers as addition inputs in agricultural systems can increase the yield of wheat and maize, while also stimulating the emission of carbon dioxide from soil that the main man-made greenhouse gas. Our objectives focused on the impact of different types of synthetic fertilizers and water quality. The purposes were to determine the feasibility of using wasted water for irrigation and to relate CO2 fluxes to the yield of maize and wheat, as well as to select the best fertilizer type with low CO2 emission and high yield. The experiment consisted of a double factors test focusing on four forms of fertilizer (urea, amine and slow release fertilizer) and the quality of water (reclaimed water and underground water). The results showed that the reclaimed water was not significant on the CO2 discharge rate, the maize-wheat yield or the soil properties in 2014 or 2015; however, the CO2 emission increased slightly in 2015. Focusing on fertilizer treatments, the reclaimed water & amine fertilizer treatment (CAF) that had higher cumulative CO2 emissions was 32.75 t·ha-1 in 2014 and 33.86 t·ha-1 in 2015. According to the ratio CO2/Y, the slow released fertilizer that reduces CO2 emissions and keeps the yield high is the preferred choice.
The intestine is the shared site of nutrient digestion, microbiota colonization and immune cell location and this geographic proximity contributes to a large extent to their interaction. The onset and development of a great many diseases, such as inflammatory bowel disease and metabolic syndrome, will be caused due to the imbalance of body immune. As competent assistants, the intestinal bacteria are also critical in disease prevention and control. Moreover, the gut commensal bacteria are essential for development and normal operation of immune system and the pathogens are also closely bound up with physiological disorders and diseases mediated by immune imbalance. Understanding how our diet and nutrient affect bacterial composition and dynamic function, and the innate and adaptive status of our immune system, represents not only a research need but also an opportunity or challenge to improve health. Herein, this review focuses on the recent discoveries about intestinal bacteria-immune crosstalk and nutritional regulation on their interplay, with an aim to provide novel insights that can aid in understanding their interactions.
Background. Evidence from experimental studies showed that Th1, Th2, and Th17 play a pivotal role in hypertension and target organ damage. However, whether changes in the circulating Th1, Th2, and Th17 levels are associated with nondipper hypertension and carotid atherosclerotic plaque in hypertension has yet to be investigated. Methods. Th1, Th2, and Th17 levels were detected using a flow cytometric analysis, and their related cytokines were measured by enzyme-linked immunosorbent assay in 45 hypertensive patients and 15 normotensive subjects. Results. The frequencies of Th1 and Th17 in hypertensive patients, especially in nondipper patients and patients with carotid atherosclerotic plaque, were markedly higher than those in the control group; this was accompanied by higher IFN-γ and IL-17 levels. In contrast, the Th2 frequencies and IL-4 levels in hypertensive patients, especially in nondipper patients and patients with carotid atherosclerotic plaque, were significantly lower than those in the control group. Conclusions. The changes in Th1, Th2, and Th17 activity are associated with the onset of the nondipper type and carotid atherosclerotic plaque in hypertensive patients.
OBJECTIVE To evaluate the mid-term clinical outcome of endoscopic greater saphenous vein harvesting (EVH) in coronary artery bypass grafting (CABG). Method A total of 205 patients receiving off-pump CABG between July, 2012 and April, 2013 at our department were enrolled in this study, including 66 patients (35 male and 31 female patients with a mean age of 60.3±7.92 years) undergoing EVH and 139 patients (109 male and 30 female patients with a mean age of 59.20±8.37 years) undergoing open greater saphenous vein harvesting (OVH). RESULTS The surgical procedures were completed smoothly in all the cases. The perioperative mortality rates was 3.03% (2/66) in EVH group, as compared with 3.60% (5/139) in OVH group (P=1.00). Acute myocardial infarction (AMI) occurred during the perioperative period in 3 (2.16%) patients in OVH group and in 1 (1.52%) patient in EVH group. Perioperative low cardiac output syndrome was diagnosed in 4 (2.88%) patients in OVH group and in 2 (3.03%) in EVH group (P>0.05). During the follow-up, 8 (8.80%) patients in OVH group and 5 (8.06%) in EVH group had recurrent angina (P=0.93). No patients experienced AMI during the follow-up. The 2-year patency rate of the venous grafts was 83.59% in OVH group and 82.22% in EVH group (P=0.73). CONCLUSION EVH has significant advantage in reducing the complications of the incision in the lower limbs. The mid-term patency rates of venous grafts are similar between OVH and EVH, but the long-term patency rate needs further evaluation.