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Abstract Background Inflammatory process results in lung injury that may lead to pulmonary fibrosis (PF). Here, we described PF in mice infected with H5N1 virus. Methods Eight-week-old BALB/c mice were inoculated intranasally with 1 × 101 MID50 of A/Chicken/Hebei/108/2002(H5N1) viruses. Lung injury/fibrosis was evaluated by observation of hydroxyproline concentrations, lung indexes, and histopathology on days 7, 14, and 30 postinoculation. Results H5N1-inoculated mice presented two stages of pulmonary disease over a 30-d period after infection. At acute stage, infected-mice showed typical diffuse pneumonia with inflammatory cellular infiltration, alveolar and interstitial edema and hemorrhage on day 7 postinoculation. At restoration stage, most infected-mice developed PF of different severities on day 30 postinoculation, and 18% of the survived mice underwent severe interstitial and intra-alveolar fibrosis with thickened alveolar walls, collapsed alveoli and large fibrotic areas. The dramatically elevated hydroxyproline levels in H5N1-infected mice showed deposition of collagen in lungs, and confirmed fibrosis of lungs. The dry lung-to-body weight ratio was significantly increased in infected group, which might be associated with the formation of PF in H5N1-infected mice. Conclusion Our findings show that H5N1-infected mice develop the typical PF during restoration period, which will contribute to the investigation of fibrogenesis and potential therapeutic intervention in human H5N1 disease.

The continuous cropping of banana in the same field may result in a serious soil-borne Fusarium wilt disease and a severe yield decline, a phenomenon known as soil sickness. Although soil microorganisms play key roles in maintaining soil health, the alternations of soil microbial community and relationship between these changes and soil sickness under banana monoculture are still unclear. Bacterial and fungal communities in the soil samples collected from banana fields with different monoculture spans were profiled by sequencing of the 16S rRNA genes and internal transcribed spacer using the MiSeq platform to explore the relationship between banana monoculture and Fusarium wilt disease in the present study. The results showed that successive cropping of banana was significantly correlated with the Fusarium wilt disease incidence. Fungal communities responded more obviously and quickly to banana consecutive monoculture than bacterial community. Moreover, a higher fungal richness significantly correlated to a higher banana Fusarium wilt disease incidence but a lower yield. Banana fungal pathogenic genus of Fusarium and Phyllosticta were closely associated with banana yield depletion and disease aggravation. Potential biocontrol agents, such as Funneliformis, Mortierella, Flavobacterium, and Acidobacteria subgroups, exhibited a significant correlation to lower disease occurrence. Further networks analysis revealed that the number of functionally interrelated modules decreased, the composition shifted from bacteria- to fungi-dominated among these modules, and more resources-competitive interactions within networks were observed after banana long-term monoculture. Our results also showed that bacterial and fungal communities were mainly driven by soil organic matter. Overall, the findings indicated that the bacterial and fungal community structures altered significantly after banana long-term monoculture, and the fungal richness, abundance of Fusarium, interactions between and within bacteria and fungi in ecological networks, and soil organic matter were associated with banana soil-borne Fusarium wilt disease. [ABSTRACT FROM AUTHOR]

Soil amended with organic amendments has been suggested to be a strategy for managing theFusariumwilt disease which severely hindered the banana production. The effects of four fertilisation regimes, including chemical fertiliser, manure composts and bio-organic fertiliser (BIO) containingBacillus amyloliquefaciensNJN-6 for 2-year continuous application on the bananaFusariumwilt disease incidence, crop yield and rhizosphere culturable microbial community were investigated. To explore the soil microflora, plate counting method,in vitroscreening method for antagonism, eco-physiological index and culture-dependent denaturing gradient gel electrophoresis method (CD DGGE) were used. The highest banana yield, culturable bacteria, actinobacteria andBacilluspopulations, culturable bacteria to fungi (B/F) value, antagonisticBacillusratio and lowestFusariumwilt disease incidence were observed in the BIO treatment. Based on CD DGGE results, the BIO application significantly altered the soil bacteria structure and showed highest richness and diversity. The phylogenetic analysis of the selected bands showed that the most abundant phyla wereProteobacteriaandBacteroidetesand BIO application enriched the generaComamonas,Chitinophaga, the speciesBacillus flexusand unculturedBacillus. All the results showed that 2-year continuous application of BIO containingB. amyloliquefaciensNJN-6 more effectively controlledFusariumwilt disease and improved fruit yields under field conditions and modulated banana rhizosphere microflora. [ABSTRACT FROM PUBLISHER]

H9N2 avian influenza viruses have repeatedly caused infections in swine and humans in some countries. The purpose of the present study was to evaluate the pulmonary pathology caused by H9N2 viral infection in mice. Six- to eight-week-old BALB/c mice were infected intranasally with 1 × 104 MID50 of A/Chicken/Hebei/4/2008(H9N2) virus. Clinical signs, pathological changes and viral replication in lungs, arterial blood gas, and cytokines in bronchoalveolar lavage fluid (BALF) were observed at different time points after infection. A control group was infected intranasally with noninfectious allantoic fluid. H9N2-infected mice exhibited severe respiratory syndrome, with a mortality rate of 60%. Gross observations showed that infected lungs were highly edematous. Major histopathological changes in infected lungs included diffuse pneumonia and alveolar damage, with neutrophil-dominant inflammatory cellular infiltration, interstitial and alveolar edema, hemorrhage, and severe bronchiolitis/peribronchiolitis. In addition, H9N2 viral infection resulted in severe progressive hypoxemia, lymphopenia, and a significant increase in neutrophils, tumor necrosis factor-α and interleukin-6 in BALF. The features described above satisfy the criteria for acute respiratory distress syndrome (ARDS). Our data show that H9N2 viral infection resulted in ARDS in mice, and this may facilitate studies of the pathogenesis of future potential H9N2 disease in humans. [ABSTRACT FROM AUTHOR]

Drylands are terrestrial ecosystems sensitive to climate change. There are totally drylands of 5.17 × 10 6  km 2 (above 80% of global total temperate desert area) in Central Asia (CAS), in which significant increases of temperature and changes of precipitation have been detected in recent decades. However, environment-induced changes in terrestrial carbon stocks of these dryland ecosystems have not been well investigated. With the Arid Ecosystem Model (AEM), this study was devoted to analyze spatiotemporal changes of carbon stocks in drylands over CAS during the past 35 years (1980-2014) and to quantify contributions to these changes of various factors, including temperature, precipitation, and atmospheric CO 2 concentration. Over the study period, total stocks of vegetation carbon (VEGC), soil organic carbon (SOC), and litter carbon (LTRC) averaged 2.8 ± 0.05 Pg C, 45.2 ± 0.01 Pg C, and 0.3 ± 0.004 Pg C(1Pg = 10 15  g) in CAS, respectively. Meanwhile, total carbon (TOTC) declined by 0.7 Pg C. Climate change caused TOTC to decrease by 1.3 Pg C. In contrast, CO 2 enrichment effect caused TOTC to increase by 0.9 Pg C. The effects of different factors on TOTC changes varied spatially. Precipitation was the dominant factor regulating TOTC change in 40.9% of the study area, mainly in the desert sparse shrub region in northwest Kazakhstan and the dryland region of southern Xinjiang of China, in which vegetation growth was mainly limited by water resource. CO 2 dominated the change of TOTC in 38.3% of the study area, mainly in the lower altitude regions of Tianshan mountain, in which the hydrothermal condition was relatively suitable for vegetation growth. Ecosystems in southern Xinjiang of China and northwest Kazakhstan are fragile to climate change., (Copyright © 2019. Published by Elsevier B.V.)