Solute transport in partially-saturated porous media plays a key role in multiple applications across scales, from the migration of nutrients and contaminants in soils to geological energy storage and recovery. Our understanding of transport in unsaturated porous media remains limited compared to the well-studied saturated case. The focus of this review is the non-reactive transport driven by the displacement of immiscible fluids, where the fluid-fluid interface acts as a barrier that limits the solute to a single fluid phase. State-of-the-art pore-scale models are described, with a critical analysis of the gaps and challenges. A numerical example is provided to demonstrate the acute sensitivity of solute transport prediction to minute, inevitable uncertainties in the spatial distribution of the fluids' velocities and interface configuration associated with the multiphase flow modeling.

Despite robots being applied in various situations of modern society, some people avoid them or do not feel comfortable interacting with them. Designs that allow robots to interact appropriately with people will make a positive impression on them resulting in a better evaluation of robots, which will solve this problem. To establish such a design, this study conducted two scenario-based experiments focusing on the politeness of the robot's conversation and behavior, and examined the impressions caused when the robot succeeds or slightly fails at a task. These two experiments revealed that regardless of whether the partner is a robot or a human, politeness not only affected the impression of interaction but also the expectations for better task results on the next occasion. Although the effect of politeness on preference toward robot agents was smaller than those toward human agents when agents failed a task, people were more likely to interact with polite robots and human agents again because they thought that they would not fail the next time. This study revealed that politeness motivates people to interact with robots repeatedly even if they make minor mistakes, suggesting that the politeness design is important for encouraging human-robot interaction.

The human ether-a-go-go-related gene (hERG) inhibition is a serious cardiac safety issue. Although the inhibition of hERG by majority of compounds are stable, the strength of the inhibition of a few compounds, including Erythromycin, is remarkably rising from room temperature (RT) to physiological temperature (PT). Understanding the features of erythromycin against hERG could help us to decide which compounds are needed for further study. The whole cell patch clamp technique was used to investigate the effects of erythromycin on hERG channels in different temperatures. We found that erythromycin caused a concentration dependent inhibition of cardiac hERG potassium channels. The half maximal inhibitory concentration (IC50) value was 1671 ± 593 μM (n = 5-10) at RT, about 11 folds higher than its IC50 (150 ± 26 μM, n = 7) at PT. Although temperature does have a profound change of hERG channel dynamic, the erythromycin further left shifted channel’s steady state activation, steady state inactivation, and make onset of inactivation significantly faster at both temperatures. It is interesting that our data suggests that there is critical binding site shifted from V625 at RT to Y652 at PT. By contrast, Cisapride, a well-known hERG blocker and its inhibition is not affected by temperature, does not change its critical binding sites after the temperature is raised to PT. The data suggests that increase strength of the inhibition could be duo to the shift of its binding sites of hERG channels.

Background: Acute respiratory illnesses (ARI) are among the major public health problems both in developed and developing countries. Studies describing about the types and magnitude of viral etiologies responsible for acute respiratory infections in Ethiopia are limited. Method: A cross sectional study was conducted on samples collected from the influenza surveillance sites in Ethiopia using Multiplex PCR. Throat/throat and nasopharyngeal swab samples were collected from the sentinel sites between January 2015 to December 2016. For the current study, samples were selected by systematic random sampling technique for detection of Parainfluenza viruses1-4 (PIV1-4), Human coronaviruses (HCoV), Human metapneumoviruses A/B (HMPV A/B); Rhinovirus (RV); Respiratory syncytial viruses A/B (RSV A/B); Human adenovirus (HAdV), Enterovirus (EV), Human parechovirus (HPeV),Human bocavirus (HBoV) and Influenza virus C (INF C). Descriptive statistics was done using SPSS version 20. Result: A total of 422 samples constituting 202 (47.9%) from male patients were tested. Among all samples 55.5% (n= 234/422) were positive for at least one respiratory virus. Respiratory viruses were co-detected in 18.2% (n=77) of the samples and 79.2% (n=61/77) were from SARI cases (p=0.007). The most frequently detected respiratory viruses were RV (18.7%), RSV A/B, (12.8%), HAdV (11.4%) and PIV1-4 (7.3%). Conclusion: The study identified range of respiratory viruses circulation among samples from ILI and SARI cases mainly among under-five children. Large scale study is recommended to better understand the seasonal variation, spectrum of illness and severity of ARI due to the different respiratory viruses.

Background and Purpose：Pulmonary fibrosis (PF) is the most common type of chronic lung disease, with a poor prognosis and a high mortality rate; however, treatment of PF is still a heavy burden. Astragaloside (AST), a major active component of Astragalus membranaceus, has demonstrated numerous pharmacological actions in a variety of diseases, including inflammation and tumors. It is worth noting that AST also plays an important role in the treatment of fibrotic diseases, but the mechanisms are still unknown. This study aims to further investigate the precise mechanisms of anti-fibrosis actin.Experimental Approach：To assess the anti-fibrosis effect of AST in PF mice, we determined the level of inflammation and collagen deposition in the lung tissue of PF mice. And we investigated whether the increased inflammation and collagen deposition shown in PF mice and human lung fibroblasts (HLF) cells are mediated by the upregulation of autophagy by inhibiting the Ras/Raf/MEK/ERK signaling pathway.Key Results: Our initial intriguing discovery was that AST has a significant therapeutic effect on reducing collagen deposition and anti-inflammatory effects in PF mice. This therapeutic effect of ATS could be attributed to autophagy activation. Additionally, siRNA-mediated autophagy deficiency exacerbates collagen deposition in HLF. Mechanistically, AST was demonstrated a functional dephosphorylation of MEK and ERK to inhibit the Ras/Raf/MEK/ERK signaling pathway, further notice autophagy was activated to varying degrees by agent depressors of Ras or MEK.Conclusion and Implications: our findings support the possibility that a therapeutic potential of AST for PF linking the de-repression mediated Ras/Raf/MEK/ERK signaling pathway via modulation of autophagy.

Background and Purpose: Alcoholic liver disease (ALD), which is induced by alcohol intake, increases the health burden worldwide. However, there is still a lack of effective drugs preventing ALD. Furfural, a small molecule that is widespread in baked goods, can limit alcohol fermentation in the microorganism and may have the potential effect to reverse the toxicity of ethanol. Experimental Approach: Human HepG2 cells were incubated with ethanol and furfural, and cell viability and the NAD+-NADH ratio were tested. Using RNA-seq to annotate the enrichment pathway, then confirmed the pathways by RT-qPCR and Western blot. Mitochondrial function tests were performed. C57BL/6J mice were fed with the Lieber-DeCarli liquid diet. Biochemical analysis of serum and histology analysis of mice livers were performed after 4 weeks. Key Results: We found that a low dose of furfural restored cell viability damaged by ethanol, normalized NAD+-NADH ratio, and upgraded PI3K-Akt pathway expression. Different concentrations of furfural have different effects on the mitochondrion: a low dose of furfural could reduce ROS production, maintain the mitochondrial transmembrane potential, and inhibit the apoptosis pathway, while a high dose of furfural has a reversed effect. In mice, furfural could mitigate the transaminase elevation induced by ethanol, reverse the lipid metabolism disorder. Conclusions and Implications: Low dose of furfural could reduce the liver toxicity of ethanol. Having food containing furfural appropriately when drinking may be a convenient and useful way to prevent ALD.

Plasmid-based reverse genetics has transformed influenza virus research by enabling the production of recombinant influenza viruses from cloned cDNA copies of viral genome segments. Reverse genetic production of influenza viruses requires cellular expression of influenza proteins polymerase basic 1, polymerase basic 2, polymerase acidic and nucleoprotein which collectively allow for transcription of viral mRNA and synthesis of new negative-sense genomic RNA, thus enabling synthesis of all components needed to assemble infectious virus from transfected cell lines. Given the importance of these proteins in the generation of influenza viruses via reverse genetics, we sought to explore how transgenic expression of mammalian-adapted PB1, PB2, PA, or NP in the 293T packaging cell line may impact the recovery of recombinant influenza viruses. We constructed four transgenic 293T cell lines expressing PB1, PB2, PA or NP derived from the mouse-adapted 2009 pandemic influenza A virus, UI182. Transgenic expression of UI182 PB2 in 293T cells enhanced recovery of replication-competent avian influenza viruses generated by reverse genetics relative to levels achieved in unmodified 293T cells. Virus recovered from PB2-expressing 293T cells replicated with kinetics that were indistinguishable from viruses recovered from unmodified 293T cells. Provision of UI182 PB2 protein via transgenic expression in 293T cells resulted in enhanced viral polymerase activity as measured by a minigenome assay, which may account for the improved efficiency of viral packaging relative to unmodified 293T cells. Transgenic expression of mammalian-adapted PB2 in 293T cells may serve as an important tool for enhancing influenza virus recovery in reverse genetic systems.

Background We aimed to evaluate whether genotype-guided warfarin dosing is superior to conventional clinical dosing for the outcomes of interest in Chinese patients. Methods - All patients with nonvalvular AF were randomly divided into two groups, genetic group and control group. We included genotypes for CYP2C9 and VKORC1 in the gene group，then doctors and pharmacists used the warfarin dosing algorithm and clinical information to determine patients’ initial dose, while in control group doses were determined by experince. The international normalized ratio (INR) measurement and standard protocols were used for further dose adjustment in both groups. The primary outcome measure was the percentage of time in the therapeutic range (%TTR) of the INR during follow up after initiation of warfarin treatment. Results The average TTR was (68.36 ± 20.57) % vs (48.52 ± 21.56) %, P<0.001) in the gene group compared with the control group. At the end of follow-up, the genetic group had a significant lower risk of cumulative incidences of ischemic stroke events in the adjusted model [relative risk (RR) 0.38 (95% CI 0.18 to 0.80), log-rank test P =0.008] than control group. There was no significant difference in the risk ratios (RR) for cumulative incidence of total bleeding events, minor bleeding events, gastrointestinal bleeding and intracerebral bleeding events between the two groups(P>0.05). Conclusion Genotype-guided dosing could improve the average TTR, improve the safety of treatment, achieve a higher level of TTR in the early anticoagulation period and reduce the risk of ischemic stroke events significantly.

Abstract Objective Arginyl-fructosyl-glucose (AFG) is an early Maillard reaction product synthesized from arginine and maltose. Although antihyperglycemic activity of AFG has been reported several times in recent years, the amelioration effect of AFG on type 2 diabetes mellitus (T2DM) remains unclear. Method T2DM was induced in mice by high fat diet (HFD) and streptozotocin (STZ). Group 1 (n = 10, CON) and Group 2 (n = 80) were fed regular chow and HFD, respectively. After 4 weeks of HFD feeding, group 2 was injected with STZ at a dose of 100 mg/kg and the fasting blood glucose (FBG) level was tested for 4 weeks post-injection. Then, mice with FBG level above 7.8 mmol/L were divided into five equally-sized groups (n=10) and they were treated with vehicle, metformin, 50, 30 and 10 mg/kg of AFG for 4 weeks, respectively, and CON was treated with vehicle. Results Orally treatment with AFG resulted in the decrease of malondialdehyde, total cholesterol, total triglyceride, daily food intake and daily water intake and increase of body weight, superoxide dismutase and insulin. The histological examination and immunohistochemistry indicate that the hypoglycemic and insulin-sensitizing capability of AFG in diabetic mice were enhanced via improving the destruction of the pancreatic islets. Conclusion All of these results indicate the therapeutic effect of AFG on T2DM mice.

This paper aims at the development of advanced process control technique that aids for the accurate on-line measurement of biomass concentration. Control of bioprocess is a challenging task mainly due to the nonlinearity of the process, complex nature of microorganisms, variations in critical parameters such as temperature, pH and agitator speed. In this study, the Event Triggered Feed Forward Control (ET-FFC) scheme is proposed and developed in order to diminish the effects of temperature, pH and DO variations during Escherichia coli ( E.coli) K-12 fed-batch. Initially, the data are collected from the laboratory scaled 3L bioreactor setup under Fed-batch operating condition and data driven models are developed using system identification techniques. Then Proportional Integral (PI) and Model Predictive Controller (MPC) feedback controllers are designed to control biomass concentration by varying feed rate of substrate and their performances are compared. To suppress the effect of known disturbances due to critical parameters, an Event Triggered Feed Forward Control (ET-FFC) is designed to change the control action when the event is detected. The closed loop performance of PI and MPC based ET-FFC are obtained in simulation and compared. The results reveal that the proposed MPC based ET-FFC scheme enhances the biomass yield. Also, the proposed control scheme helps to reduce the frequency of communication between controller and actuator which leads to reduction in power consumption.

Background and Purpose Tibetan medicine is one of the oldest traditional medicine systems in the world. Taking the Ruyi Zhenbao tablet (RYZB) as an example, which is a widely used classic oral Tibetan medicine, this article discusses the pharmacokinetics of single administration and long-term treatment, analyzed its metabolic properties and tissue distribution in vivo. Experimental approach After single administration, blood samples were collected before administration and different time points after administration in different groups of rats. In the study of long-term treatment effects, blood samples were collected from the animals in each group on days 1, 15, 30, and on day 15 after withdrawal. Key Results After a single administration, the dose change had no significant effect on the T1/2 and Tmax of agarotetrol, isoliquiritigenin, and piperine (p > 0.05). There was a certain correlation between the increase in AUC0-t and the Cmax of agarotetrol, isoliquiritigenin, piperine, and the increase in dosage; dose range of 0.225-0.900 g/kg. There were no significant differences in Cmax and AUC0-t of ferulic acid at different doses (p > 0.05). Conclusion and Implications Through the establishment of the previously developed methodology, the pharmacokinetic properties of RYZB were analyzed after single administration and long-term administration. Our findings confirmed this approach for the exploration and establishment of a pharmacokinetic evaluation of Tibetan medicine, to support its guiding role in clinical application, but also to accelerate research into Tibetan medicine theory and medicine and to provide a solid foundation for the translation of Tibetan medicine throughout the world.

Objective To investigate the independent and joint effects of insulin resistance and β-cell dysfunction on reproductive outcomes in women with polycystic ovary syndrome (PCOS) undergoing in-vitro fertilization (IVF). Design A single-centre, retrospective cohort study. Population Infertile women with PCOS undergoing their first IVF cycle between September 2010 and December 2019. Methods Insulin resistance and β-cell dysfunction were measured by homeostasis model assessment of insulin resistance (HOMA-IR) and the HOMA of β-cell function (HOMA-β) index, respectively. Data of reproductive outcomes were analyzed according to the quartile groups of HOMA-IR and HOMA-β. Main outcome measures Main outcome measure was miscarriage rate. Results In quartiles of HOMA-IR, the incidence of miscarriage dramatically increased from 7.4% (Q1) to 32.6% (Q4) (P for trend <0.001). Likewise, the incidence of miscarriage in quartiles of HOMA-β also showed the similar trend (P for trend < 0.001). In terms of the live birth rate in quartiles of HOMA-IR and HOMA-β, there exhibited a significantly decreasing trend in both unadjusted model and adjusted models. Women with the highest HOMA-IR and the highest HOMA-β group exhibited the highest risk for miscarriage (RR=5.16, 95%CI 3.26-8.17) compared with all other groups. Furthermore, higher HOMA-IR value was associated with higher risk of miscarriage among participants regardless the levels of HOMA-β values. Conclusions Both β-cell dysfunction and insulin resistance are independently and synergistically associated with increased risk of miscarriage in women with PCOS, and the influence of insulin resistance overweighs that of β-cell dysfunction.

From 10 patients with acute cervical insufficiency and prospectively collected amniotic fluid, the relationship between intra-amniotic sludge (IAS) and proteomic profile is described. An abundance of keratinizing proteins were seen with IAS; without sludge, inflammatory proteins were predominant. Proteomic profiling may provide unique insights into management of these high-risk pregnancies.

Introduction |Shellfish allergy is an important cause of food allergies worldwide. Both in vivo and in vitro diagnostics failure nowadays is caused by the poor quality of the extracts associated with the scarce availability of allergenic molecules in the market. It is known that not all patients with shellfish allergies experience adverse reactions to mollusks. It is still unclear how to detect and diagnose correctly these patients. Aim |To investigate the features of shrimp-allergic patients either reactive or tolerant to mollusks, with the currently available diagnostic methods. Methods| Nineteen centers, scattered throughout Italy, participated in the study, enrolling patients allergic to shrimp with or without associated reactions to mollusks. Patients underwent skin tests using commercial extracts or fresh raw and cooked foods, and IgE reactivity to currently available allergenic extracts and molecules was measured in vitro. Results| Two hundred and forty-seven individuals with a history of adverse reaction to crustaceans participated in the study. Only 47.8% of them reacted after cephalopod or bivalve ingestion. None of the tests used, either in vivo or in vitro, was able to detect all selected patients. Accordingly, a great heterogeneity of results was observed with an agreement between in vivo and in vitro tests ranging between 52% and 62% of cases. Skin tests were able to identify the cephalopod and bivalve reactors (p <0.001), also using fresh cooked or raw food (p <0.001). The reactivity profile of mollusk reactors was dominated by Pen m 1, over Pen m 2 and Pen m 4 compared to the tolerant subjects, but 33% of patients allergic to shellfish were not detected by any of the available molecules. A higher frequency of shrimp hypersensitivity was recorded in northern Italy, while mollusk reactivity was more frequent in the center-south. Conclusion |The current diagnostic methods are inadequate to predict the cross-reactivity between crustaceans and mollusks. The detection of mollusks hypersensitivity must still rely on skin tests with fresh material. There is no need to exclude mollusks from shrimp allergic patients’ diet unless clinical history, the available diagnostic instruments, and/or tolerance tests support such a decision. Primary sensitization to mollusks seems possible.

Background Considering the course of the current SARS CoV 2 pandemic, it is important to have serological tests for the detection of the anti-SARS CoV-2 humoral immune response for monitoring and prognosis the different stages of the disease. Purpose Herein we describe a novel bridge enzyme-linked immunosorbent assay (b-ELISA) for SARS-CoV-2 antibodies detection in human and other species, employing recombinant Spike protein as a unique antigen, which is produced at high scale in insect larvae. Results Eighty two human control sera/plasmas and 169 COVID-19 patients’ sera/plasmas, confirmed by rRT-PCR, were analysed by the b-ELISA assay. Out of the 169 patient samples, 129 were positive for IgG anti-SARS-CoV-2 and 40 were negative when they were tested by ELISA COVIDAR® IgG. When a cut-off value of 5.0 SDs was established, 124 out of the 129 COVID-19 positive samples were also positive by our developed b-ELISA (sensitivity: 96.12%). A total of 27 animal sera (5 horses, 13 rats, 2 cats and 7 dogs) were employed in order to evaluate the b-ELISA in other animal species. Conclusion The obtained results demonstrate that the method developed herein is versatile, as it is able to detect antibodies anti-SARS-CoV-2 in different animal species without the need to perform and optimize a new assay for each species.

Background: Successful treatment of IgE mediated allergies by allergen-specific immunotherapy (AIT) usually correlates with the induction of allergen-specific IgG4. However, it is not clear whether IgG4 prevents the allergic reaction more efficiently than other IgG subclasses. Here we aimed to compare allergen-specific monoclonal IgG1 and IgG4 antibodies in their capacity to inhibit type I allergic reactions by engaging FcγRIIb. Methods: Three monoclonal antibodies (F127, A044 and G078) against Fel d 1, the major cat allergen in humans, recognizing three non-overlapping epitopes of Fel d 1 were tested for their capacity to block human basophils activation in vitro. The affinity of the three monoclonal antibodies in IgG1 and IgG4 formats to FcgRIIb were investigated by Biolayer Interferometry. Results: We found that IgG1, which is the dominant subclass induced by viruses, binds with a similar affinity to the FcγRIIb as IgG4 and is comparable at blocking human basophil activation from allergic patients; both by neutralizing the allergen as well as engaging the inhibitory receptor FcγRIIb. Conclusion: Hence, the IgG subclass plays a limited role for the protective efficacy of AIT even if IgG4 is considered the best correlate of protection because it is the dominant subclass induced by classical AITs.

An 83 year-old man underwent attempted cardiac resynchronization therapy (CRT-P), but was found to have a persistent left superior vena cava (SVC) and absence of a right SVC. Additionally, no suitable coronary sinus (CS) veins were found. Instead, conduction system pacing with a modified approach was used.

Introduction: Shared decision-making (SDM) can support patients with atrial fibrillation (AF) to evaluate treatment options for rhythm and symptom control, but studies suggest it is not occurring meaningfully in routine practice. The objective of this study was to measure decision quality and describe decision-making processes among patients and clinicians involved in decision-making around catheter ablation for AF. Methods: We conducted a cross-sectional, mixed-methods study guided by a SDM model outlining decision antecedents, processes, and outcomes. Patients and clinicians completed semi-structured interviews about decision-making around ablation, feelings of decision conflict and regret, and preferences for the content, delivery, and format of a hypothetical decision aid for ablation. Patients also completed surveys about demographic characteristics and literacy levels, AF symptoms using the University of Toronto AF Severity Scale (AFSS), and aspects of decision quality using the Controls-Preferences, Decisional Conflict, and Decision Regret scales. Surveys were analyzed using descriptive statistics and qualitative data were analyzed using directed content analysis. Results: Fifteen patients (mean age 71.1 ± 8.6 years; 27% female; mean 7.0 [SD 7.0] months since ablation) and five clinicians (three physicians, one NP, and one PA) were recruited. Most patients preferred to either share or relinquish control in medical decision-making to clinicians. For most patients, decisional conflict and regret were low, and symptoms and cardiac health generally improved after ablation. However, they also reported low levels of information and agency in the decision-making process. Most clinicians report routinely providing patients with information and encouraging engagement during consultations. Patients reported preferences for an interactive, web-based decision aid that clearly presents evidence regarding outcomes using data, visualizations, videos, and personalized risk assessments, and is available in multiple languages. Conclusions: Disconnects between clinician efforts to provide information and bolster agency and patient experiences of decision-making suggest decision aids may be needed to improve decision quality in practice. Reported experiences with current decision-making practices and preferences for decision aid content, format, and delivery can support the user-centered design and development of a decision aid.

In this paper we are interested in the existence of nontrivial solutions for a class of variable exponent $p(x)$-Kirchhoff type equations. We are able to prove the existence of three solutions by using the mountain pass theorem and Ekeland’s variational principle. Moreover, when $\lambda =0$, we obtain the existence of infinite many solutions by using symmetric mountain pass theorem.

A 75-year-old woman presenting with dyspnea and chest pain underwent cardiac catheterization revealing three-vessel coronary artery disease with severe calcific aortic stenosis and dilated aortic root (Figure 1). A multi-gated acquisition scan (MUGA) was performed revealing LVEF to be 50%, reassuring consensus to proceed with aortic valve replacement and concomitant coronary artery bypass grafting. She was brought to the cardiovascular operating room (CVOR) in stable condition. Routine cardioplegia ensued after placement on cardiopulmonary bypass and grafting was performed to the obtuse marginal, posterior descending, and left anterior descending arteries. Upon successful grafting, attention shifted to the aorta. A transverse incision was made 2cm above the annulus, exposing the valve. A severely thickened, unicuspid, unicommisural aortic valve was observed (Figure 2) and replaced with a 23mm Edwards ® Inspiris TM valve. Unicuspid unicommisural aortic valves are rare manifestations with a prevalence of 0.02% 1. They precipitate congenital aortic stenosis in patients within the first 4th-6th decades of life 2. Outcomes are promising with aortic valve replacement 3. Herein, we showcase this anomaly manifesting symptomatically in a septuagenarian, with successful surgical replacement and coronary bypass grafting.

Microfauna and meiofauna organisms are often overlooked in traditional diversity assessments due to their small size and difficulty to morphologically identify. Metabarcoding is an emerging method for the rapid identification of organisms. Environmental DNA (eDNA) is often used as a template for metabarcoding, but legacy DNA is problematically detected from organisms no longer in the environment during sampling. Environmental RNA (eRNA) can also be collected and sequenced using the same pipeline as eDNA metabarcoding, but it is only produced by living organisms. The aim of this study was to determine the differences in detected community composition and diversity between eRNA and eDNA templates for downstream metabarcoding. Seven field-collected mesocosms from the Narrow River Estuary in Narragansett, RI (USA) were held in a flow-through seawater laboratory for 14 days to ensure no residual DNA contamination from non-living organisms. RNA and DNA were co-extracted from the top layer of sediment, libraries were prepared for two loci (18S V4 region and Cytochrome c Oxidase subunit 1) and sequenced using an Illumina MiSeq. Results show a higher number of unique sequences detected from eRNA in both the 18S and COI markers and higher α-diversity compared to eDNA. Significant differences between eRNA and eDNA for all β-diversity metrics were also detected. This study is the first to demonstrate community differences detected with eRNA compared to eDNA from a dynamic estuarine system under controlled laboratory conditions and start to illustrate the broad applications of eRNA as a tool for assessing benthic community diversity.

The leaf microbiota plays a key role in plant development, but a detailed mechanism of microbe-plant relationships remains elusive. Many genome-wide association studies (GWAS) have begun to map leaf microbes, but few has systematically characterized the genetics of how microbes act and interact. Previously, we integrated behavioral ecology and game theory to define four types of microbial interactions – mutualism, antagonism, aggression, and altruism, in a microbial community assembly. Here, we apply network mapping to identify specific plant genes that mediate the topological architecture of microbial networks. Analyzing leaf microbiome data from an Arabidopsis GWAS, we identify several heritable hub microbes for leaf microbial communities and detect 140-728 SNPs responsible for emergent properties of microbial network. We reconstruct Bayesian genetic networks from which to identify 22-43 hub genes found to code molecular pathways related to leaf growth, abiotic stress responses, disease resistance and nutrition uptake. A further path analysis visualizes how genetic variants of Arabidopsis affect its fecundity through the internal workings of the leaf microbiome. We find that microbial networks and their genetic control vary along spatiotemporal gradients. Our study provides a new avenue to reveal the “endophenotype” role of microbial networks in linking genotype to end-point phenotypes in plants.

​​ Microbial volatile organic compounds (mVCs) are a part of a collection of microbial secondary metabolites with biological effects on all living organisms. mVCs could function as gaseous modulators of plant growth and plant health. In this study, the defense events induced by plant-deleterious mVCs were investigated. E. aerogenes VCs lead to growth inhibition and plant defense responses such as callose deposition, and ROS accumulation in Arabidopsis thaliana. Data from transcriptional analysis suggests that genes involved in the hypoxia response pathway were enriched in the short exposure up-regulated genes, E. aerogenes VCs induced high transactivation of defense, immune, and metabolic processes after long exposure. In addition, the transcript abundance of the genes involved in the synthetic pathways of antimicrobial metabolites camalexin and coumarin was enhanced after the E. aerogenes VCs exposure. MKK1 and MKK3 were identified as the regulators of the camalexin biosynthesis expression and E. aerogenes VCs-induced callose deposition. The transactivation activity of the coumarin biosynthesis pathway was only regulated by MKK3. Collectively, these studies provide molecular insights into immune responses by plant-deleterious mVCs.

Microcystins are natural hepatotoxic metabolites secreted by cyanobacteria in aquatic ecosystems. When present at elevated concentrations, microcystins can affect water quality aesthetics, contaminate drinking water reservoirs and recreational waters, disrupt normal ecosystem functioning, and cause health hazards to animals, plants, and humans. Animal and human exposures to microcystins generally results from ingesting contaminated drinking water or physically contacting tainted water. Much research has identified a multitude of liver problems from oral exposure to microcystins, varying from hepatocellular damage to primary liver cancer. Provisional guidelines for microcystins in drinking and recreational water have been established to prevent toxic exposures and protect public health. With increasing occurrences of eutrophication in freshwater systems, microcystin contamination in groundwater and surface waters is growing, posing threats to aquatic and terrestrial plants, and agricultural soils for crop production. These microcystins are often transferred to crops via irrigation with local sources of water, such as bloom-forming lakes and ponds. Microcystins can survive in high quantities in various parts of plants (roots, stems, and leaves) due to their high chemical stability and low molecular weight, increasing health risks for consumers of agricultural products. Studies have indicated potential health risks associated with contaminated fruits and vegetables sourced from irrigated water containing microcystins. This mini-review compounds the exposure risk to humans, plants, and the environment due to the presence of microcystins in local waterways used for drinking and irrigation. Additional studies are needed to understand the specific health impacts associated with the consumption of microcystin-contaminated agricultural plants.