Combined System of Organic Substrate and Straw-Degrading Microbial Agents Improved Soil Organic Matter Levels and Microbial Abundance in a Rice-Wheat Rotation.

Rice-wheat rotation is one of the most intensive agricultural planting modes in China and is pivotal to develop optimized straw-returning management in situ to improve soil fertility and productivity in agricultural ecosystems. Previous studies have mainly focused on the effects of straw return with a single application of organic fertilizers. The integrated management of different fertilizers in improving the management of straw return in situ is not well known. In this study, a field experiment was conducted from 2017 to 2019 to explore the effects of a combined system of modified organic substrate (MOS) and straw-degrading compound microbial agent (CMA) on soil physiochemical properties, labile organic carbon, microbial activities, and soil microbial community composition under the background of direct crop straw return and chemical fertilizer utilization. Four treatments were designed: (1) control check; (2) CMA; (3) MOS; and (4) MOS + CMA. The results showed that the MOS + CMA treatment had the combined advantages of soil organic matter (SOM) accumulation, soil nutrient increase and soil microbial community alteration, which may be more suitable for improving the quality and fertility of sandy loam soil. This study provides novel insights for further understanding the effects of organic substrates and composite microbial agents on SOM changes and microbial community composition and function in the field, which has important implications for sustainable crop production and agricultural development.

Flowering-mediated root-fungus symbiosis loss is related to jasmonate-dependent root soluble sugar deprivation.

The role of flowering in root-fungal symbiosis is not well understood. Because flowering and fungal symbionts are supported by carbohydrates, we hypothesized that flowering modulates root-beneficial fungal associations through alterations in carbohydrate metabolism and transport. We monitored fungal colonization and soluble sugars in the roots of Arabidopsis thaliana following inoculation with a mutualistic fungus Phomopsis liquidambari across different plant developmental stages. Jasmonate signalling of wild-type plants, sugar transport, and root invertase of wild-type and jasmonate-insensitive plants were exploited to assess whether and how jasmonate-dependent sugar dynamics are involved in flowering-mediated fungal colonization alterations. We found that flowering restricts root-fungal colonization and activates root jasmonate signalling upon fungal inoculation. Jasmonates reduce the constitutive and fungus-induced accumulation of root glucose and fructose at the flowering stage. Further experiments with sugar transport and metabolism mutant lines revealed that root glucose and fructose positively influence fungal colonization. Diurnal, jasmonate-dependent inhibitions of sugar transport and soluble invertase activity were identified as likely mechanisms for flowering-mediated root sugar depletion upon fungal inoculation. Collectively, our results reveal that flowering drives root-fungus cooperation loss, which is related to jasmonate-dependent root soluble sugar depletion. Limiting the spread of root-fungal colonization may direct more resources to flower development.

Influenza H7N9 and H9N2 viruses: coexistence in poultry linked to human H7N9 infection and genome characteristics.

UNLABELLED: Avian influenza virus A of the novel H7N9 reassortant subtype was recently found to cause severe human respiratory infections in China. Live poultry markets were suspected locations of the human H7N9 infection sources, based on the cases' exposure histories and sequence similarities between viral isolates. To explore the role of live poultry markets in the origin of the novel H7N9 virus, we systematically examined poultry and environmental specimens from local markets and farms in Hangzhou, using real-time reverse transcription-PCR (RT-PCR) as well as high-throughput next-generation sequencing (NGS). RT-PCR identified specimens positive for the H7 and N9 genomic segments in all of the 12 poultry markets epidemiologically linked to 10 human H7N9 cases. Chickens, ducks, and environmental specimens from the markets contained heavily mixed subtypes, including H7, N9, H9, and N2 and sometimes H5 and N1. The idea of the coexistence of H7N9 and H9N2 subtypes in chickens was further supported by metagenomic sequencing. In contrast, human H7N9 infection cases (n = 31) were all negative for H9N2 virus according to real-time RT-PCR. The six internal segments were indistinguishable for the H7N9 and H9N2 viruses. The H9, N2, and internal-segment sequences were very close to the sequence of the H9N2 virus circulating in chickens in China recently. Our results provide direct evidence that H9N2 strains coexisted with the novel human-pathogenic H7N9 influenza virus in epidemiologically linked live poultry markets. Avian influenza A virus of the H9N2 subtype likely made a recent contribution to the evolution of the H7N9 virus and continues to do so. IMPORTANCE: Our results suggest that avian influenza A virus of the H9N2 subtype likely made a recent contribution to the evolution of the H7N9 virus, a novel reassortant avian influenza virus A subtype, and continues to do so. The finding helps shed light on how the H7N9 virus emerged, spread, and transmitted to humans. It is of considerable interest for assessing the risk of the possible emergence of novel reassortant viruses with enhanced transmissibility to humans.

Protective effect of manganese treatment on insulin resistance in HepG2 hepatocytes.

Introduction: Objectives: manganese (Mn) is closely related to type 2 diabetes mellitus and insulin resistance (IR), but the exact mechanism is unclear. This study aimed to explore the regulatory effects and mechanism of Mn on IR using hepatocyte IR model induced by high palmitate (PA), high glucose (HG) or insulin. Methods: HepG2 cells were exposed to PA (200 µM), HG (25 mM) or insulin (100 nM) respectively, alone or with 5 µM Mn for 24 hours. The expression of key proteins in insulin signaling pathway, intracellular glycogen content and glucose accumulation, reactive oxygen species (ROS) level and Mn superoxide dismutase (MnSOD) activity were detected. Results: compared with control group, the expression of phosphorylated protein kinase B (Akt), glycogen synthase kinase-3ß (GSK-3ß) and forkhead box O1 (FOXO1) in the three IR groups was declined, and this decrease was reversed by Mn. The reduction of intracellular glycogen content and increase in glucose accumulation in IR groups were also inhibited by Mn. Additionally, the production of ROS was increased in IR models, compared with normal control group, while Mn reduced the excessive production of ROS induced by PA, HG or insulin. However, Mn did not alter the activity of MnSOD in the three IR models. Conclusion: this study demonstrated that Mn treatment can improve IR in hepatocytes. The mechanism is probably by reducing the level of intracellular oxidative stress, enhancing the activity of Akt/GSK-3ß/FOXO1 signal pathway, promoting glycogen synthesis, and inhibiting gluconeogenesis.

Introducción: Objetivos: el manganeso (Mn) está estrechamente relacionado con la diabetes mellitus tipo 2 y la resistencia a la insulina (RI), pero el mecanismo exacto aún no está claro. Este estudio tuvo como objetivo explorar los efectos reguladores y el mecanismo del Mn sobre la RI utilizando un modelo de RI en hepatocitos inducido por palmitato alto (PA), glucosa alta (HG) o insulina. Métodos: las células HepG2 se expusieron a PA (200 µM), HG (25 mM) o insulina (100 nM), solas o junto con 5 µM de Mn durante 24 horas. Se evaluó la expresión de proteínas clave en la vía de señalización de la insulina, el contenido intracelular de glucógeno y la acumulación de glucosa, el nivel de especies reactivas de oxígeno (ROS) y la actividad superóxido dismutasa del manganeso (MnSOD). Resultados: en comparación con el grupo de control, la expresión de proteína quinasa B fosforilada (Akt), la glucógeno sintasa quinasa-3ß (GSK-3ß) y la proteína forkhead box O1 (FOXO1) en los tres grupos de RI se redujo, y esta disminución fue revertida por el Mn. La reducción del contenido de glucógeno intracelular y el aumento de la acumulación de glucosa en los grupos de RI también fueron inhibidos por el Mn. Además, la producción de ROS aumentó en los modelos de RI en comparación con el grupo de control normal. Mientras que el Mn redujo la producción excesiva de ROS inducida por PA, HG o insulina. Sin embargo, el Mn no alteró la actividad de la MnSOD en los tres modelos de RI. Conclusión: este estudio demostró que el tratamiento con Mn puede mejorar la RI en hepatocitos. El mecanismo probablemente sea mediante la reducción del nivel de estrés oxidativo intracelular, mejorando la actividad de la vía de señalización Akt/GSK-3ß/FOXO1, promoviendo la síntesis de glucógeno e inhibiendo la gluconeogénesis.

Effects of multi-phase inoculation on the fungal community related with the improvement of medicinal herbal residues composting.

Composting has become the most important way to recycle medicinal herbal residues (MHRs). The traditional composting method, adding a microbial agent at one time, has been greatly limited due to its low composting efficiency, mutual influence of microbial agents, and unstable compost products. This study was conducted to assess the effect of multi-phase inoculation on the lignocellulose degradation, enzyme activities, and fungal community during MHRs composting. The results showed that multi-phase inoculation treatment had the highest thermophilic temperature (68.2 °C) and germination index (102.68%), significantly improved available phosphorus content, humic acid, and humic substances concentration, accelerated the degradation of cellulose and lignin, and increased the activities of cellulase in the mature phase, xylanase, manganese peroxidase, and utilization of phenolic compounds. Furthermore, the non-metric multi-dimensional scaling showed that the composting process and inoculation significantly influenced fungal community composition. In multi-phase inoculation treatment, Thermomyces in mesophilic, thermophilic, and mature phase, unclassified_Sordariales, and Coprinopsis in mature phase were the dominant genus that might be the main functional groups to degrade lignocellulose and improve the MHRs composting process.

Nitrogen fertilizer-regulated plant-fungi interaction is related to root invertase-induced hexose generation.

The mechanisms underlying nitrogen (N)-regulated plant-fungi interactions are not well understood. N application modulates plant carbohydrate (C) sinks and is involved in the overall plant-fungal association. We hypothesized that N regulates plant-fungi interactions by influencing the carbohydrate metabolism. The mutualistic fungus Phomopsis liquidambaris was found to prioritize host hexose resources through in vitro culture assays and in planta inoculation. Rice-Ph. liquidambaris systems were exposed to N gradients ranging from N-deficient to N-abundant conditions to study whether and how the sugar composition was involved in the dynamics of N-mediated fungal colonization. We found that root soluble acid invertases were activated, resulting in increased hexose fluxes in inoculated roots. These fluxes positively influenced fungal colonization, especially under N-deficient conditions. Further experiments manipulating the carbohydrate composition and root invertase activity through sugar feeding, chemical treatments and the use of different soil types revealed that the external disturbance of root invertase could reduce endophytic colonization and eliminate endophyte-induced host benefits under N-deficient conditions. Collectively, these results suggest that the activation of root invertase is related to N deficiency-enhanced endophytic colonization via increased hexose generation. Certain combinations of farmland ecosystems with suitable N inputs could be implemented to maximize the benefits of plant-fungi associations.

Protective effect of manganese treatment on insulin resistance in Hepg2 hepatocytes / Efecto protector del tratamiento con manganeso sobre la resistencia a la insulina en hepatocitos HepG2

Objectives: manganese (Mn) is closely related to type 2 diabetes mellitus and insulin resistance (IR), but the exact mechanism is unclear. This study aimed to explore the regulatory effects and mechanism of Mn on IR using hepatocyte IR model induced by high palmitate (PA), high glucose (HG) or insulin. Methods: HepG2 cells were exposed to PA (200 μM), HG (25 mM) or insulin (100 nM) respectively, alone or with 5 μM Mn for 24 hours. The expression of key proteins in insulin signaling pathway, intracellular glycogen content and glucose accumulation, reactive oxygen species (ROS) level and Mn superoxide dismutase (MnSOD) activity were detected. Results: compared with control group, the expression of phosphorylated protein kinase B (Akt), glycogen synthase kinase-3β (GSK-3β) and forkhead box O1 (FOXO1) in the three IR groups was declined, and this decrease was reversed by Mn. The reduction of intracellular glycogen content and increase in glucose accumulation in IR groups were also inhibited by Mn. Additionally, the production of ROS was increased in IR models, compared with normal control group, while Mn reduced the excessive production of ROS induced by PA, HG or insulin. However, Mn did not alter the activity of MnSOD in the three IR models. Conclusion: this study demonstrated that Mn treatment can improve IR in hepatocytes. The mechanism is probably by reducing the level of intracellular oxidative stress, enhancing the activity of Akt/GSK-3β/FOXO1 signal pathway, promoting glycogen synthesis, and inhibiting gluconeogenesis.(AU)

Objetivos: el manganeso (Mn) está estrechamente relacionado con la diabetes mellitus tipo 2 y la resistencia a la insulina (RI), pero el mecanismoexacto aún no está claro. Este estudio tuvo como objetivo explorar los efectos reguladores y el mecanismo del Mn sobre la RI utilizando un modelode RI en hepatocitos inducido por palmitato alto (PA), glucosa alta (HG) o insulina.Métodos: las células HepG2 se expusieron a PA (200 μM), HG (25 mM) o insulina (100 nM), solas o junto con 5 μM de Mn durante 24 horas.Se evaluó la expresión de proteínas clave en la vía de señalización de la insulina, el contenido intracelular de glucógeno y la acumulación deglucosa, el nivel de especies reactivas de oxígeno (ROS) y la actividad superóxido dismutasa del manganeso (MnSOD).Resultados: en comparación con el grupo de control, la expresión de proteína quinasa B fosforilada (Akt), la glucógeno sintasa quinasa-3β(GSK-3β) y la proteína forkhead box O1 (FOXO1) en los tres grupos de RI se redujo, y esta disminución fue revertida por el Mn. La reduccióndel contenido de glucógeno intracelular y el aumento de la acumulación de glucosa en los grupos de RI también fueron inhibidos por el Mn.Además, la producción de ROS aumentó en los modelos de RI en comparación con el grupo de control normal. Mientras que el Mn redujo laproducción excesiva de ROS inducida por PA, HG o insulina. Sin embargo, el Mn no alteró la actividad de la MnSOD en los tres modelos de RI.Conclusión: este estudio demostró que el tratamiento con Mn puede mejorar la RI en hepatocitos. El mecanismo probablemente sea mediantela reducción del nivel de estrés oxidativo intracelular, mejorando la actividad de la vía de señalización Akt/GSK-3β/FOXO1, promoviendo la síntesisde glucógeno e inhibiendo la gluconeogénesis.(AU)

Characterization of human bocavirus-like particles generated by recombinant baculoviruses.

Human bocavirus (HBoV) is a nonenveloped, single-stranded DNA virus, classified recently into the genus Bocavirus in the family Parvoviridae. A recombinant baculovirus expression system was used to express the major capsid protein VP2 of HBoV1, HBoV2, HBoV3 and HBoV4 in insect cells. A large amount of the 61-kDa VP2 capsid protein (p61) of HBoVs was generated and efficiently released into the supernatant. The capsid protein was self-assembled into 22-nm-dia. virus-like particles (VLPs) with a buoyant density of 1.30g/cm(3). The morphology of HBoVs-LPs was similar to that of the native HBoV particles, and immunogenic studies demonstrated the cross-reactivity among HBoV1, HBoV2, HBoV3 and HBoV4. When VP1 and VP2 protein of HBoV1 were co-expressed in insect cells, both proteins were detected in the same fraction after CsCl gradient centrifugation, suggesting that the VP1 protein is a minor structural protein of HBoVs. We developed an ELISA using purified VLPs as the antigen and used it to detect antibodies against HBoV1, HBoV2, HBoV3 and HBoV4. A high prevalence of antibodies against HBoVs was found in a general population of healthy Japanese, indicating that HBoVs have spread throughout Japan.

The release rate of curcumin from calcium alginate beads regulated by food emulsifiers.

Curcumin-loaded alginate beads, which contain different food emulsifiers, have been prepared using CaCl2 as the cross-linking agent. The controlled release of the curcumin from the beads was investigated at room temperature. For calcium alginate/Span-80/Tween-80 (A/S/T) formulations, almost all of the curcumin loaded in the beads was released into the medium within about 20 h, and the release rates could be regulated by changing the concentration of both Tween-80 and Span-80. However, for the systems of calcium alginate/Q-12A/F-18A (A/Q/F), about 60% of the curcumin loaded in the beads was released at the end of experiments. The studies of scanning electron microscopy indicated that the microstructure of the walls of beads could significantly vary with the concentration or type of emulsifiers. The Fourier transform infrared spectral measurements confirmed that the interactions between calcium alginate and polyglycerol fatty acid esters were stronger than that between calcium alginate and Tween-80/Span-80. The results of swelling studies demonstrated that the initial rates of water uptake for A/Q/F beads were higher than that for A/S/T beads. Moreover, the data of release rates were fitted by an empirical equation, which showed that the release mechanism of curcumin from the alginate gels varied with the composition of emulsifiers for the A/S/T systems. This work provides an important insight into the effect of food emulsifiers on the release rates of the curcumin from calcium alginate beads and will be helpful for the application of the systems in controlled release of other hydrophobic drug.

Risk factors for hand, foot, and mouth disease and herpangina and the preventive effect of hand-washing.

BACKGROUND: Hygiene and social distancing are recommended control measures for hand, foot, and mouth disease (HFMD) and herpangina. However, empirical data to support this recommendation are limited. METHODS: During an outbreak of HFMD and herpangina due to infection by the human enterovirus 71, we defined a case as a vesicular papular rash on the hands, feet, buttocks, or oral mucosa and onset from April 30 to June 26, 2008. We selected 176 HFMD and herpangina case-children and a stratified random sample of 201 asymptomatic control-children; frequency matched according to residency status. We administered a questionnaire to the parents about their children's exposures and hygienic behaviors. RESULTS: Risk factors for HFMD and herpangina included playing with neighborhood children (odds ratio [OR]: 11 [95% confidence interval (CI): 6.2-17]), visiting an outpatient clinic for another reason ≤ 1 week before onset (OR: 20 [95% CI: 5.0-88]), and community exposures to crowded places (OR: 7.3 [95% CI: 4.1-13]). By using a score summarizing responses to 4 hand-washing questions, we found that 50% of the case-children and 2.5% of control-children had a poor score of 1 to 3, whereas 12% of the case-children and 78% of control-children had a good score of ≥ 7 (OR: 0.00069 [95% CI: 0.0022-0.022]) after we adjusted for residency, age, and community exposures by using logistic regression. CONCLUSIONS: Hand-washing by preschool-aged children and their caregivers had a significant protective effect against community-acquired HFMD and herpangina from the human enterovirus 71 infection.

[Study on the use of TaqMan Real-time PCR to detect genogroup I and II norovirus in oysters and patients' stool samples].

OBJECTIVE: To develop a rapid, specific and sensitive diagnostic method for quantification and typing of genogroup I and II norovirus in oyster shellfish and stool samples from patients who had eaten them. METHODS: Specific primers and probe, following large scale norovirus genome consensus analysis were designed and subsequently a TaqMan based Real-time PCR assay to detect both GI and GII were established. RESULTS: This method showed high specificity for norovirus nucleic acid detection, and no cross-reaction among norovirus GI and GII. The limit on detection of NV genomes was 10(2) copies/microl. A total of 90 oysters and 37 stool specimens with diarrhea were tested for norovirus by conventional reverse transcriptional PCR (RT-PCR) assay as well as the TaqMan Real-time PCR, respectively. The norovirus detection rate in oysters by TaqMan PCR was significantly higher than that by conventional RT-PCR, but no differences between the two PCR methods were found when detecting the stool samples. Reliability of the Real-time PCR for norovirus detection was further confirmed by DNA sequencing of the positive samples CONCLUSION: This TaqMan Real-time PCR assay was proved to be a useful method for quantification and typing for norovirus in routine monitoring of both oyster shellfish and clinical samples. This method is recommended to be an effective diagnostic method for outbreak-associated gastroenteritis due to norovirus.