SARS-CoV-2 ORF8 Protein Induces Endoplasmic Reticulum Stress-like Responses and Facilitates Virus Replication by Triggering Calnexin: an Unbiased Study.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the viral pathogen responsible for the worldwide coronavirus disease 2019 (COVID-19) pandemic. The novel SARS-CoV-2 ORF8 protein is not highly homologous with known proteins, including accessory proteins of other coronaviruses. ORF8 contains a 15-amino-acid signal peptide in the N terminus that localizes the mature protein to the endoplasmic reticulum. Oligomannose-type glycosylation has been identified at the N78 site. Here, the unbiased molecular functions of ORF8 are also demonstrated. Via an immunoglobulin-like fold in a glycan-independent manner, both exogenous and endogenous ORF8 interacts with human calnexin and HSPA5. The key ORF8-binding sites of Calnexin and HSPA5 are indicated on the globular domain and the core substrate-binding domain, respectively. ORF8 induces species-dependent endoplasmic reticulum stress-like responses in human cells exclusively via the IRE1 branch, including intensive HSPA5 and PDIA4 upregulation, with increases in other stress-responding effectors, including CHOP, EDEM and DERL3. ORF8 overexpression facilitates SARS-CoV-2 replication. Both stress-like responses and viral replication induced by ORF8 have been shown to result from triggering the Calnexin switch. Thus, ORF8 serves as a key unique virulence gene of SARS-CoV-2, potentially contributing to COVID-19-specific and/or human-specific pathogenesis. IMPORTANCE Although SARS-CoV-2 is basically regarded as a homolog of SARS-CoV, with their genomic structure and the majority of their genes being highly homologous, the ORF8 genes of SARS-CoV and SARS-CoV-2 are distinct. The SARS-CoV-2 ORF8 protein also shows little homology with other viral or host proteins and is thus regarded as a novel special virulence gene of SARS-CoV-2. The molecular function of ORF8 has not been clearly known until now. Our results reveal the unbiased molecular characteristics of the SARS-CoV-2 ORF8 protein and demonstrate that it induces rapidly generated but highly controllable endoplasmic reticulum stress-like responses and facilitates virus replication by triggering Calnexin in human but not mouse cells, providing an explanation for the superficially known in vivo virulence discrepancy of ORF8 between SARS-CoV-2-infected patients and mouse.

Phytochrome B mediates dim-light-reduced insect resistance by promoting the ethylene pathway in rice.

Increasing planting density is one of the most effective ways to improve crop yield. However, one major factor that limits crop planting density is the weakened immunity of plants to pathogens and insects caused by dim light (DL) under shade conditions. The molecular mechanism underlying how DL compromises plant immunity remains unclear. Here, we report that DL reduces rice (Oryza sativa) resistance against brown planthopper (BPH; Nilaparvata lugens) by elevating ethylene (ET) biosynthesis and signaling in a Phytochrome B (OsPHYB)-dependent manner. The DL-reduced BPH resistance is relieved in osphyB mutants, but aggravated in OsPHYB overexpressing plants. Further, we found that DL reduces the nuclear accumulation of OsphyB, thus alleviating Phytochrome Interacting Factor Like14 (OsPIL14) degradation, consequently leading to the up-regulation of 1-Aminocyclopropane-1-Carboxylate Oxidase1 (OsACO1) and an increase in ET levels. In addition, we found that nuclear OsphyB stabilizes Ethylene Insensitive Like2 (OsEIL2) by competitively interacting with EIN3 Binding F-Box Protein (OsEBF1) to enhance ET signaling in rice, which contrasts with previous findings that phyB blocks ET signaling by facilitating Ethylene Insensitive3 (EIN3) degradation in other plant species. Thus, enhanced ET biosynthesis and signaling reduces BPH resistance under DL conditions. Our findings provide insights into the molecular mechanism of the light-regulated ET pathway and host-insect interactions and potential strategies for sustainable insect management.

Ionic Hyperbranched Poly(amido-amine)-Incorporated Nanofiltration Membranes for High-Efficiency Dye Desalination.

High-efficiency dye desalination is crucial in the textile industry, considering its importance for human health, safe aquatic ecological systems, and resource recovery. In order to solve the problem of effective separation of univalent salt and ionic dye under the condition of high salt, ionic hyperbranched poly(amido-amine) (HBPs) were synthesized based on a simple and scalable one-step polycondensation method and then incorporated into the polyamide (PA) selective layers to construct charged nanochannels through interfacial polymerization (IP) on the surface of a polyvinyl chloride ultrafiltration (PVC-UF) hollow fiber membrane. Both the internal nanopores of HBPs (internal nanochannels) and the interfacial voids between HBPs and the PA matrix (external nanochannels) can be regarded as a fast water molecule transport pathway, while the terminal ionic groups of ionic HBPs endow the nanochannels with charge characteristics for improving ionic dye/salt selectivities. The permeate fluxes and dye/salt selectivities of HBP-TAC/PIP (57.3 L m-2 h-1 and rhodamine B (RB)/NaCl selectivity of 224.0) and HBP-PS/PIP (63.7 L m-2 h-1 and lemon yellow (LY)/NaCl selectivity of 664.0) membranes under 0.4 MPa operation pressure are much higher than PIP-only and HBP-NH2/PIP membranes. At the same time, this project also studied the membrane desalination process in a simulated high-salinity dye/salt mixture system to provide a theoretical basis and technical support for the actual dye desalination process.

Research on the Properties of Wasteforms after Direct Involvement of Uranium-Containing Silica Gel in Glass Network Formation.

Uranium-containing silica gel (UCSG) is a secondary waste generated during the advanced treatment of nuclear wastewater. In order to reduce the growing storage pressure for UCSG, from the perspective of building a borosilicate glass network, UCSG was used to replace SiO2 in the glass-cured formula to directly achieve the immobilization of UCSG. SEM-EDS results showed that uranium was uniformly distributed in the matrix, and the maximum solid solubility of UCSG (two components: silica gel and uranyl ions) in the formula was as high as 55 wt %. At the same time, TG-MS proved that silica gel lost OH groups (down about 4.61 wt %) and formed Si-O-Si bond by condensation. FT-IR and XPS proved a change in the number of Si-O-Si bond, and new Si-O-B and Si-O-Al bond appeared on the spectrum. This was evidence that silica gel could self-involved participate in the construction of glass networks. EPR analysis obtained the changes in the coordination environment of U atom, the U atom decreased spin electrons number in the glass than in uranyl crystals. The glass also has good physical properties (hardness: 6.51 ± 0.23 GPa; density: 2.3977 ± 0.0056 g/cm3) and chemical durability (normalized leaching rate: LRU = 2.34 × 10-4 ± 2.05 × 10-6 g·m2·days-1 after 42 days), this research provided tactics for simple treatment of uranium-containing silica gel in one step.

Value of serum iron and urine neutrophil gelatinase-associated lipocalin in predicting the mortality of critically ill patients with sepsis.

INTRODUCTION: We aimed to investigate the association of iron metabolism-related parameters with 60-day mortality in critically ill patients with sepsis. METHODS: Serum or urine concentrations of iron metabolism-related parameters on intensive care unit admission were measured in a prospective cohort of 133 eligible patients with sepsis according to the Sepsis-3 criteria, and these values were compared between survivors and nonsurvivors, categorized according to their 60-day survival status. Cox regression analyses were performed to examine the association between iron parameters and 60-day mortality. Kaplan-Meier methods were used to illustrate the differences in survival between different iron parameters. RESULTS: Of the 133 patients included in the study, 61 (45.8%) had died by day 60. After adjusting for confounding variables, higher concentrations of serum iron (cut-off 9.5 µmol/mL) and higher concentrations of urine neutrophil gelatinase-associated lipocalin (uNGAL; cut-off 169.3 ng/mL) were associated with a significantly greater risk of death in the Cox regression analysis. These two biomarkers combined with Sequential Organ Failure Assessment (SOFA) scores increased the area under the receiver operating characteristic (AUROC) curve to 0.85. DISCUSSION: These findings suggest that higher concentrations of serum iron and uNGAL are each associated with higher 60-day mortality, and they add significant accuracy to this prediction in combination with SOFA. Abbreviations: uNGAL: urine neutrophil gelatinase-associated lipocalin; ICU: intensive care unit; SOFA: Sequential Organ Failure Assessment; APACHE II: the Acute Physiology and Chronic Health Evaluation II; ELISA: enzyme-linked immunosorbent assay; HR: hazard ratio; CIs: confidence intervals; WBC: white blood cell; TBIL: total bilirubin.

Identification and mechanism characterization of Streptomyces griseoaurantiacus XQ-29 with biocontrol ability against pepper southern blight caused by Sclerotium rolfsii.

Pepper southern blight, caused by Sclerotium rolfsii, is a devastating soil-borne disease resulting in significant loss to pepper, Capsicum annuum L. production. Here, we isolated an antagonistic bacterial strain XQ-29 with antifungal activity against S. rolfsii from rhizospheric soil of pepper. Combining the morphological and biochemical characteristics with the 16S rDNA sequencing, XQ-29 was identified as Streptomyces griseoaurantiacus. It exhibited an inhibition of 96.83% against S. rolfsii and displayed significant inhibitory effects on Botrytis cinerea, Phytophthora capsica and Rhizoctonia solani. Furthermore, XQ-29 significantly reduced the pepper southern blight by 100% and 70.42% during seedling and growth stages, respectively. The antifungal mechanism involved altering the mycelial morphology, disrupting cell wall and membrane integrity, accompanied by accumulation of reactive oxygen species and lipid peroxidation in S. rolfsii mycelia. Furthermore, XQ-29 promoted growth and stimulated resistance of pepper plants by increasing defense-related enzyme activities and upregulating defense-related genes. Correspondingly, XQ-29 harbors numerous functional biosynthesis gene clusters in its genome, including those for siderophores and melanin production. The metabolic constituents present in the ethyl acetate extracts, which exhibited an EC50 value of 85.48 ± 1.62 µg/mL, were identified using LC-MS. Overall, XQ-29 demonstrates significant potential as a biocontrol agent against southern blight disease.

Characterization and biocontrol mechanism of Streptomyces olivoreticuli as a potential biocontrol agent against Rhizoctonia solani.

Rhizoctonia solani is a widespread and devastating plant pathogenic fungus that infects many important crops. This pathogen causes tobacco target spot, a disease that is widespread in many tobacco-growing countries and is destructive to tobacco. To identify antagonistic microorganisms with biocontrol potential against this disease, we isolated Streptomyces strains from forest inter-root soil and screened a promising biocontrol strain, ZZ-21. Based on in vitro antagonism assays, ZZ-21 showed a significant inhibitory effect on R. solani and various other phytopathogens. ZZ-21 was identified as Streptomyces olivoreticuli by its phenotypic, genetic, physiological and biochemical properties. Complete genome sequencing revealed that ZZ-21 harbored numerous antimicrobial biosynthesis gene clusters. ZZ-21 significantly reduced the lesion length in detached inoculated leaf assays and reduced the disease index under greenhouse and field conditions. Based on an in vitro antagonistic assay of ZZ-21 culture, the strain exhibited an antifungal activity against R. solani in a dose-dependent manner. The culture filtrate could impair membrane integrity, possibly through membrane lipid peroxidation. ZZ-21 could secrete multiple extracellular enzymes and siderophores. According to a series of antifungal assays, the extracellular metabolites of ZZ-21 contained antimicrobial bioactive compounds composed of proteins/peptides extracted using ammonium sulfate precipitation, which were stable under stress caused by high temperature and protease K. The EC50 value for ammonium sulfate precipitation was determined to be 21.11 µg/mL in this study. Moreover, the proteins/peptides also exhibited biocontrol ability and were observed to alter the plasma membrane integrity of R. solani which were evaluated by biocontrol efficacy assays on detached tobacco leaves and PI staining. Overall, strain ZZ-21 shows the potential to be developed into a biopesticide against tobacco target spot disease.

First Report of Colletotrichum siamense Causing Anthracnose on Dioscorea alata in China.

Dioscorea alata is an annual or perennial dicotyledonous plant which is a vegetatively propagated tuberous food crop (Mondo et al. 2021). In 2021, symptoms of leaf anthracnose occurred on D. alata plants at a plantation in Changsha, the Hunan Province of China (28°18' N; 113°08'E). Symptoms initially showed as small, brown water-soaked spots on the leaf surface or margins, and enlarged to irregular, dark brown or black, necrotic lesions, with a lighter center and darker edge. At latter, lesions extended to most of the leaf surface causing leaf scorch or wilting. Almost 40% of the plants surveyed were infected. Symptomatic leaf samples were collected, and small pieces were taken at their disease-healthy junction, sterilized with 70% ethanol for 10 s, 0.1% HgCl2 for 40 s, rinsed three times with sterile distilled water, and then placed on potato dextrose agar (PDA) for incubation at 26 °C for 5 days in the dark. Fungal colonies with similar morphology were observed and, in total, 10 isolates were obtained from 10 plants. On PDA, colonies were initially white with fluffy hyphae, and later became light to dark gray, showing faint concentric rings. Conidia were hyaline, aseptate, cylindrical, and rounded at both ends, measuring 11.36 to 17.67 × 3.45 to 5.9 µm (n = 50). Appressoria were dark brown, ovate, globose, measuring 6.37 to 7.55 × 10.11 to 12.3 µm. These morphological characteristics were typical of Colletotrichum gloeosporioides species complex (Weir et al. 2012). For molecular identification, the internal transcribed spacer (ITS) region of rDNA, and partial sequences of actin (ACT), chitin synthase (CHS-1), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes of a representative isolate Cs-8-5-1 were amplified and sequenced using the primer pairs ITS1/ITS4, ACT-512F/ACT-783R, CHS-79F/CHS-354R, and GDF/GDR as described previously (Weir et al. 2012). These sequences were deposited in GenBank (accession nos. OM439575 for ITS, OM459820 for ACT, OM459821 for CHS-1, and OM459822 for GAPDH). BLASTn analysis showed 99.59 to 100 % identity to the corresponding sequences of C. siamense strains. A Maximum likelihood phylogenetic tree based on the concatenated ITS, ACT, CHS-1 and GAPDH sequences was generated by MEGA 6. It revealed that the Cs-8-5-1 was clustered with the C. siamense strain CBS 132456 with 98% bootstrap support. For pathogenicity test, conidia suspension (105 spores/ml) was prepared by harvesting conidia from 7-day-old cultures growing on PDA, and 10 uL was dropped onto leaves of potted D. alata plants (8 droplets per leaf). Leaves treated with sterile water were served as controls. All the inoculated plants were placed in humid chambers (with 90% humidity) at 26°C with a photoperiod of 12 h. The pathogenicity tests were performed twice, with each had three replicated plants. Seven days after inoculation, the inoculated leaves showed symptoms of brown necrosis resembling that observed in fields, however, the control leaves remained symptomless. The fungus was specifically re-isolated and identified by morphological and molecular methods, thus fulfilling Koch's postulates. To our knowledge, this is the first report of C. siamense causing anthracnose on D. alata in China. Since this disease might seriously affect the photosynthesis of the plants, which can influence the yield, prevention and management strategies should be adopted to control this new disease. Identification of this pathogen will provide a foundation for the diagnosis and control of this disease.

First Report of Stemphylium lycopersici Causing Leaf spot on Sedum plumbizincicola in Hunan Province of China.

Sedum plumbizincicola is a perennial succulent herb that can hyperaccumulate high concentrations of cadmium and zinc (Liu et al. 2017). In October 2021, a leaf spot disease occurred on S. plumbizincicola seedlings in a nursery in Changsha (28°13' N; 112°56'E), the Hunan Province of China. Almost 30% of the nearly 1 million seedlings were infected. Symptoms initially appeared as small brown spots on the leaf surface or edges, gradually enlarged, becoming oval, and bearing chlorotic lesions with dark brown borders. Eventually, the center of the lesions became sunken and then fell off. Eight symptomatic plant samples were collected by five-point sampling method (Zheng et al. 2018). Small pieces of 5×5 mm were excised from the lesion margins, sterilized with 70% ethanol for 10 s, 0.1% HgCl2 for 40 s, rinsed with sterile distilled water three times, and then cultured on potato dextrose agar (PDA) at 26 °C for 5 days in the dark. Fungal colonies showing similar morphology were observed from all the isolated samples and, in total, eight fungal strains were obtained. On PDA, fungal colonies were initially white, and later become light gray. After cultured on V8 juice agar (V8A, each litre of medium contains 200 mL of V8 juice, 3 g of CaCO3 and 15 g of agarose) for 14 days (Hyowon et al. 2016), conidia of a representative isolate SY-1 were produced, which were oblong, muriform, with blunt ends and conical apex, pale to light brown, and constricted at the 1 to 3 major transverse septa, 38.34-46.68 µm×11.67-18.34 µm (n=50). These morphological characteristics were consistent with that of Stemphylium lycopersici (Nasehi et al. 2016). The internal transcribed spacer (ITS) region of rDNA and the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene of representative isolates SY-1 to SY-3 were amplified and sequenced using the primer pairs ITS4/ITS5 and gpd1/gpd2 as described previously (Woudenberg et al. 2017). BLASTn analysis showed that ITS sequences of isolates SY-1, SY-2 and SY-3 (accession nos. OP317641, OQ852042 and OQ852043) had more than 99% identity with Stemphylium sp, while GAPDH sequences (OP331223, OQ858620 and OQ858621) had 100% identity with S. lycopersici KR911813 (Sun et al. 2016). A concatenated ITS-GAPDH phylogenetic tree grouped our isolates within the S. lycopersici clade. For the pathogenicity test, one-month-old potted S. plumbizincicola seedlings were inoculated with conidia suspension (105 conidia/ml), which was induced on V8A. Four sites of each leaf of the potted S. plumbizincicola plants were dropped with a conidia suspension of strain SY-1, with 10 µL per site. Leaves treated with sterile water were served as controls. All of the inoculated seedlings were placed in a growth chamber at 26°C with a photoperiod of 12 h. The pathogenicity tests were repeated twice, with each had three replicative plants. After 7 days, all the inoculated leaves developed brown spots resembling those observed in the nursery, whereas the control plants remained symptomless. Stemphylium lycopersici was specifically re-isolated and identified by morphological and molecular methods (accession nos. OQ852045 for ITS and OQ858622 for GAPDH, respectively), thus fulfilling Koch's postulates. To our knowledge, this is the first report of S. lycopersici causing leaf spot on S. plumbizincicola in China. Since S. plumbizincicola played an important role and widely planted for heavy metal pollution treatment (Jiang et al. 2010), and this disease might seriously influence the S. plumbizincicola seedling breeding, identification of the pathogen might provide a foundation for the diagnosis and control of the disease.

Usage of compromised lung volume in monitoring steroid therapy on severe COVID-19.

BACKGROUND: Quantitative computed tomography (QCT) analysis may serve as a tool for assessing the severity of coronavirus disease 2019 (COVID-19) and for monitoring its progress. The present study aimed to assess the association between steroid therapy and quantitative CT parameters in a longitudinal cohort with COVID-19. METHODS: Between February 7 and February 17, 2020, 72 patients with severe COVID-19 were retrospectively enrolled. All 300 chest CT scans from these patients were collected and classified into five stages according to the interval between hospital admission and follow-up CT scans: Stage 1 (at admission); Stage 2 (3-7 days); Stage 3 (8-14 days); Stage 4 (15-21 days); and Stage 5 (22-31 days). QCT was performed using a threshold-based quantitative analysis to segment the lung according to different Hounsfield unit (HU) intervals. The primary outcomes were changes in percentage of compromised lung volume (%CL, - 500 to 100 HU) at different stages. Multivariate Generalized Estimating Equations were performed after adjusting for potential confounders. RESULTS: Of 72 patients, 31 patients (43.1%) received steroid therapy. Steroid therapy was associated with a decrease in %CL (- 3.27% [95% CI, - 5.86 to - 0.68, P = 0.01]) after adjusting for duration and baseline %CL. Associations between steroid therapy and changes in %CL varied between different stages or baseline %CL (all interactions, P < 0.01). Steroid therapy was associated with decrease in %CL after stage 3 (all P < 0.05), but not at stage 2. Similarly, steroid therapy was associated with a more significant decrease in %CL in the high CL group (P < 0.05), but not in the low CL group. CONCLUSIONS: Steroid administration was independently associated with a decrease in %CL, with interaction by duration or disease severity in a longitudinal cohort. The quantitative CT parameters, particularly compromised lung volume, may provide a useful tool to monitor COVID-19 progression during the treatment process. Trial registration Clinicaltrials.gov, NCT04953247. Registered July 7, 2021, https://clinicaltrials.gov/ct2/show/NCT04953247.

Mortality and serum hepcidin are associated with persistent and transient acute kidney injury in septic patients.

PURPOSE: Acute kidney injury (AKI) is a common complication of sepsis and has high mortality. The 2017 Acute Disease Quality Initiative (AQDI) workgroup proposed new definitions for AKI - transient AKI and persistent AKI; however, very little is known about the effect of transient and persistent septic AKI on short-term mortality among critically ill patients with sepsis. The purpose of this study was to assess the impact of persistent AKI on mortality and to evaluate whether serum hepcidin can predict the occurrence of persistent AKI in critically ill patients with sepsis. MATERIALS AND METHODS: This prospective observational study was performed in a general hospital mixed surgical-medical ICU in Pudong, China. Consecutive adults with sepsis admitted to the ICU with absence of chronic kidney disease, renal transplant, and AKI were included. AKI was defined according to the KDIGO criteria and classified as transient (< 48-hour duration) or persistent (48-hour duration). Blood samples were obtained within 6 hours from when AKI was diagnosed. RESULTS: A total of 90 patients with sepsis or septic shock were included in the analysis. 44 (48.89%) patients developed AKI during ICU stay: 20 (45.45%) had transient and 24 (54.55%) had persistent AKI. Persistent AKI has a higher mortality than transient AKI (66.7 vs. 30.0%, p = 0.002). Persistent AKI and sequential organ failure assessment (SOFA) scores were an independent predictor of 60-day mortality. Patients with persistent AKI had higher concentrations of serum creatinine (SCr) and hepcidin than transient AKI patients when AKI was diagnosed. Logistic regression indicated that serum hepcidin was an independent predictor of persistent AKI in septic patients, with a fairly predictive value (AUC 0.71, 95% CI: 0.47 - 0.87; p = 0.02). CONCLUSION: Persistent AKI was associated with increased 60-day mortality compared with transient AKI in septic patients. The serum hepcidin levels measured when AKI was diagnosed have a fair predictive value to predict the occurrence of persistent AKI in septic patients.

Two Isostructural Flexible Porous Coordination Polymers Showing Contrasting Single-Component and Mixture Adsorption Properties for Propylene/Propane.

Solvothermal reactions of 3-(3-methylpyridin-4-yl)benzoic acid (Hmpba) with Mn(NO3)2 or Co(NO3)2 yielded isostructural porous coordination polymers, [Mn(mpba)2]·guest (MCF-56, 1·g) and [Co(mpba)2]·guest (MCF-57, 2·g), respectively. X-ray diffraction revealed that 1·g and 2·g possess similar one-dimensional ultramicroporous channels, and guest-free [Mn(mpba)2] (1') and [Co(mpba)2] (2') possess significantly and slightly contracted channels, respectively. Single-component C3H6/C3H8 adsorption isotherms and computational simulations showed the typical nonporous-to-porous structural transformations for 1', in which C3H6 exhibits a significantly lower threshold pressure, and the typical small-pore-to-large-pore structural transformations for 2', in which C3H6 exhibits a slightly lower threshold pressure. Mixture column breakthrough experiments showed that the C3H6/C3H8 separation performances of 2' are obviously better than those of 1', because the latter cannot adsorb C3H6 below the threshold pressure for pore opening, and the pore opened by C3H6 can adsorb C3H8.

A Hydrogen-Bonded yet Hydrophobic Porous Molecular Crystal for Molecular-Sieving-like Separation of Butane and Isobutane.

Porous molecular crystals sustained by hydrogen bonds and/or weaker connections are an intriguing type of adsorbents, but they rarely demonstrate efficient adsorptive separation because of poor structural robustness and tailorability. Herein, we report a porous molecular crystal based on hydrogen-bonded cyclic dinuclear AgI complex, which exhibits exceptional hydrophobicity with a water contact angle of 134°, and high chemical stability in water at pH 2-13. The seemingly rigid adsorbent shows a pore-opening or nonporous-to-porous type butane adsorption isotherm and complete exclusion of isobutane, indicating potential molecular sieving. Quantitative column breakthrough experiments show slight co-adsorption of isobutane with an experimental butane/isobutane selectivity of 23, and isobutane can be purified more efficiently than for butane. In situ powder/single-crystal X-ray diffraction and computational simulations reveal that a trivial guest-induced structural transformation plays a critical role.

Activation of RAS/ERK alone is insufficient to inhibit RXRα function and deplete retinoic acid in hepatocytes.

Activation of RAS/ERK signaling pathway, depletion of retinoid, and phosphorylation of retinoid X receptor alpha (RXRα) are frequent events found in liver tumors and thought to play important roles in hepatic tumorigenesis. However, the relationships among them still remained to be elucidated. By exploring the transgenic mouse model of hepatic tumorigenesis induced by liver-specific expression of H-ras12V oncogene, the activation of RAS/ERK, the mRNA expression levels of retinoid metabolism-related genes, the contents of retinoid metabolites, and phosphorylation of RXRα were determined. RAS/ERK signaling pathway was gradually and significantly activated in hepatic tumor adjacent normal liver tissues (P) and hepatic tumor tissues (T) of H-ras12V transgenic mice compared with normal liver tissues (Wt) of wild type mice. On the contrary, the mRNA expression levels of retinoid metabolism-related genes were significantly reduced in P and T compared with Wt. Interestingly, the retinoid metabolites 9-cis-retinoic acid (9cRA) and all-trans-retinoic acid (atRA), the well known ligands for nuclear transcription factor RXR and retinoic acid receptor (RAR), were significantly decreased only in T compared with Wt and P, although the oxidized polar metabolite of atRA, 4-keto-all-trans-retinoic-acid (4-keto-RA) was significantly decreased in both P and T compared with Wt. To our surprise, the functions of RXRα were significantly blocked only in T compared with Wt and P. Namely, the total protein levels of RXRα were significantly reduced and the phosphorylation levels of RXRα were significantly increased only in T compared with Wt and P. Treatment of H-ras12V transgenic mice at 5-week-old or 5-month-old with atRA had no effect on the prevention of tumorigenesis or cure of developed nodules in liver. These events imply that the depletion of 9cRA and atRA and the inhibition of RXRα function in hepatic tumors involve more complex mechanisms besides the activation of RAS/ERK pathway.

A novel partitivirus conferring hypovirulence by affecting vesicle transport in the fungus Colletotrichum.

Colletotrichum spp. are economically important phytopathogenic fungi that cause anthracnose in a variety of plant species worldwide. Hypovirulence-associated mycoviruses provide new options for the biological control of plant fungal diseases. Here, we found a novel partitivirus from Colletotrichum alienum and named it Colletotrichum alienum partitivirus 1 (CaPV1). CaPV1 contained two dsRNA segments encoding an RNA-dependent RNA polymerase and a capsid protein and was classified under the genus Gammapartitivirus of the family Partitiviridae. CaPV1 significantly decreased host virulence, mycelial growth, appressorial development, and appressorium turgor but increased conidial production with abnormal morphology. In addition, CaPV1 could be successfully transfected into other Colletotrichum species, including C. fructicola, C. spaethianum, and C. gloeosporioides, and caused hypovirulence, indicating the broad application potential of this virus. CaPV1 caused significant transcriptional rewiring of the host fungus C. alienum. Notably, some genes related to vesicle transport in the CaPV1-infected strain were downregulated, consistent with the impaired endocytosis pathway in this fungus. When the Rab gene CaRab7, which is associated with endocytosis in vesicle transport, was knocked out, the virulence of the mutants was reduced. Overall, our findings demonstrated that CaPV1 has the potential to control anthracnose caused by Colletotrichum, and the mechanism by which Colletotrichum induces hypovirulence is caused by affecting vesicle transport.IMPORTANCEColletotrichum is a kind of economically important phytopathogenic fungi that cause anthracnose disease in a variety of plant species worldwide. We found a novel mycovirus of the Gammapartitivirus genus and Partitiviridae family from the phytopathogenic fungus Colletotrichum alienum and named it CaPV1. This study revealed that CaPV1 infection significantly decreased host virulence and fitness by affecting mycelial growth, appressorial development, and appressorium turgor. In addition, CaPV1 could also infect other Colletotrichum species, including C. fructicola, C. spaethianum, and C. gloeosporioides, by viral particle transfection and resulting in hypovirulence of these Colletotrichum species. Transcriptomic analysis showed that CaPV1 caused significant transcriptional rewiring of the host fungus C. alienum, especially the genes involved in vesicle transport. Moreover, endocytosis and gene knockout assays demonstrated that the mechanism underlying CaPV1-induced hypovirulence is, at least in part, caused by affecting the vesicle transport of the host fungus. This study provided insights into the mechanisms underlying the pathogenesis of Colletotrichum species and mycovirus-fungus interactions, linking the role of mycovirus and fungus vesicle transport systems in shaping fungal pathogenicity.

Increased expression of dectin-1 in nasal polyps.

PURPOSE: A fungal etiology has been proposed to underlie severe nasal polyps (NP). Dectin-1 is an innate immune pattern recognition receptor which is involved in the recognition of some pathogenic fungi. We investigated the Dectin-1 levels in NP in order to evaluate the implication of such expression with respect to the development of NP. MATERIALS AND METHODS: Normal inferior turbinate tissues were obtained from forty patients undergoing surgery for augmentation rhinoplasty. Nasal polyp tissues were obtained from 53 patients who underwent endoscopic sinus surgery for chronic polypoid rhinosinusitis. Real-time polymerase chain reaction and Western blot analysis were performed to evaluate the mRNA and protein level of Dectin-1, respectively. ELISA was carried out to evaluate the cytokine production (IL-4, IL-5, IL-10, and TNF-α) in NP. RESULTS: Real-time polymerase chain reaction and Western-blot analysis showed that Dectin-1 expression in NP was increased compared with that in normal nasal inferior turbinate tissues. ELISA results suggest that the local expression of type-1 and type-2 inflammatory cytokine is skewed toward type-2 inflammatory cytokine in NP. CONCLUSIONS: These results suggest that Dectin-1 may play a role in the development of NP, and the production of Dectin-1, IL-4 and IL-5 (type-2 cytokines), may mainly participate in the inflammatory reaction in NP.

[Effect of shufeng xuanfei recipe and jiebiao qingli recipe on mRNA and protein expressions of TLR7, MyD88, and NF-kappaB in mice infected with influenza virus].

OBJECTIVE: To observe effect of Shufeng Xuanfei Recipe (SXR) and Jiebiao Qingli Recipe (JQR) on mRNA and protein expressions of Toll-like receptor 7 (TLR7), myeloid differentiation factor 88 (MyD88), and nuclear factor-kappaB (NF-kappaB) in mice infected with influenza virus FM1. METHODS: One hundred and eight mice were randomly divided into nine groups, i.e., the normal control group, the model group, the Oseltamivir group (at the daily dose of 2.5 g/mL), the high dose SXR group (at the daily dose of 3.762 g/kg), the middle dose SXR group (at the daily dose of 1.881 g/kg), the low dose SXR group (at the daily dose of 0.941 g/kg), the high dose JQR group (at the daily dose of 4.368 g/kg), the middle dose JQR group (at the daily dose of 2.184 g/kg), and the low dose JQR group (at the daily dose of 1.092 g/kg), 12 in each group. All mice were mildly anesthetized by ether. Mice in the normal control group were treated by nasal drop of 0.05 mL normal saline, while mice in the rest groups were infected by nasal drop of 0.05 mL influenza virus strain FM1 (LD50). The successful modeling rate was 100%. All medication was performed by gastrogavage 2 h after infection. Distilled water was given by gastrogavage to mice in the normal control group and the model group at the daily dose of 0.2 mL, each time per day for 4 successive days. mRNA expressions of TLR7, MyD88, and NF-kappaB in the lung tissue were determined by Western blot. RESULTS: Compared with the normal control group, mRNA expressions of TLR7, MyD88, and NF-kappaB increased in the model group (P < 0.01). Compared with the model group, mRNA and protein expressions of TLR7, MyD88, and NF-kappaB decreased in the Oseltamivir group, the high, middle, and low dose SXR groups (P < 0.05, P < 0.01); mRNA and protein expressions of TLR7 and NF-kappaB decreased in the high and middle dose JQR groups (P < 0.05, P < 0.01); mRNA expressions of MyD88 decreased in the high and middle dose JQR groups (P < 0.05); protein expressions of MyD88 decreased in the middle dose JQR group (P < 0.05); protein expressions of TLR7 and NF-kappaB decreased in the low dose JQR group (P < 0.05). Compared with the Oseltamivir group, protein expressions of MyD88 decreased in the low dose SXR group (P < 0.05); protein expressions of NF-kappaB decreased in the middle and low dose SXR groups (P < 0.01); mRNA and protein expressions of TLR7 (P < 0.05, P < 0.01), and protein expressions of MyD88 (P < 0.01) decreased in the high, middle, and low dose JQR groups; mRNA and protein expressions of NF-kappaB decreased in the low dose JQR group (P < 0.05, P < 0.01). CONCLUSIONS: Each dose SXR and middle dose JQR could down-regulating the activity of NF-kappaB through adjusting MyD88 dependent TLR signal pathway, thus fighting against influenza virus. SXR was more effective than JQR.

[Clinical efficacy of shenfu injection in treating severe sepsis and its effects on serum levels of interleukin-6 and interleukin-10].

OBJECTIVE: To observe the therapeutic efficacy of Shenfu Injection (SFI) on patients with severe sepsis and its effects on serum levels of interleukin-6 (IL-6) and interleukin-10 (IL-10). METHODS: Sixty-eight patients with severe sepsis were randomly assigned to the SFI group (36 cases, treated by SFI + routine therapy) and the control group (32 cases, treated by routine therapy). The acute physiology and chronic health evaluation II (APACHE II) score and Marshall score were observed before treatment, 3 and 7days after treatment. The therapeutic efficacy was assessed, and the 28th-day mortality rates were compared. The serum levels of IL-6 and IL-10 were determined by enzyme-labeled immunosorbent assay (ELISA) before and after treatment. C-reactive protein (CRP) was determined by immunoturbidimetric assay. RESULTS: There was no significant difference in the APACHE II score, Marshall score, IL-6, IL-10, or CRP between the two groups before treatment (P>0.05). APACHE II score and Marshall score of all patients decreased after treatment, with more obvious decrease shown in the SFI group (P<0.05). The mortality rate in the SFI group and the control group was 25.0% (9/36) and 37.5% (12/32) respectively, with no significant difference shown between the two groups (P>0.05). The serum levels of IL-6 and CRP obviously decreased after 7 days of treatment (P<0.05). But more decrement was shown in the SFI group, showing significant difference when compared with the control group (P<0.05). There was no significant difference in the serum IL-10 level between the two groups before and after treatment (P>0.05). CONCLUSION: SFI could lower the serum IL-6 level, regulate the equilibrium of proinflammatory factors and anti-inflammatory cytokines in severe sepsis patients, thus playing a role in improving the therapeutic efficacy.

[The clinical analysis of 18 cases with acute trichloropropane poisoning].

OBJECTIVE: To summarise the clinical features of 18 cases with acute trichloropropane (TCP) poisoning for improving the diagnosis and treatment of the disease. METHODS: Exposure history, clinical manifestations, laboratorial examinations, poisoning causes and treatment were retrospectively reviewed in 18 cases with acute TCP poisoning. The results of peripheral lymphocyte micronucleus tests were compared with the healthy control group (n = 33). RESULTS: The common clinical symptoms were as following: respiratory symptoms were the earlier one set, such as chest tightness in 13, dry and sore throat in 7, cough and runny nose in 2. Gastrointestinal symptoms were more common, such as abdominal pain in 18, nausea and vomit in 14. Only 1 out of 18 patients was found with liver injury. The major manifestation was the increase in ALT and AST, which was returned to normal after treatment. ALL of the 18 patients were found TCP in their serum which concentration was from 39.0 to 310.0 ng/ml, and the average was (68.9 ± 42.1) ng/ml. The symptoms of toxic peripheral neuropathy were typical in all the patients, such as fatigue and numb limb in 18, burning pain of the distal lower limbs in 14, the symmetrical sock-like sensory dysfunction of pain, touch and vibration of the lower limbs in 13, muscle strength reduced in 7, hyporeflexia knee-jerks in 4, hyporeflexia ankle-jerks in 3. The peripheral nerve conduction velocity (NCV) examinations were as followed: the (sensore-nerve conduction velocity) SCV of peroneus super nerve in 18 and the (motor-nerve conduction velocity) MCV of tibial nerve in 8 was slowed down and the distal latency in 18 was prolonged. Micronucleus were found in all 18 cases. The micronucleus rate was 10.06‰ ± 2.80‰ and 8.24‰ ± 2.67‰ in acute TCP poisoning group and healthy control group, respectively. The difference was significant (P < 0.05). CONCLUSION: The common clinical manifestations of respiratory exposure of TCP poisoning patients were respiratory symptoms, gastrointestinal symptoms and the symptoms of toxic peripheral neuropathy. Liver injury in those 18 cases was not obvious. Lymphocyte micronucleus of peripheral blood were found in all 18 cases.

Blocking VCAM-1 ameliorates hypertensive cardiac remodeling by impeding macrophage infiltration.

Cardiac remodeling is an important mechanism of heart failure, which frequently results from leukocyte infiltration. Vascular cellular adhesion molecule-1 (VCAM-1) plays a critical role in leukocyte adhesion and transmigration. However, the importance of VCAM-1 in the development of angiotensin II (Ang II)-induced cardiac remodeling remains unclear. Wild-type (WT) mice were infused with Ang II (1,000 ng/kg/min) for 14 days and simultaneously treated with VCAM-1 neutralizing antibody (0.1 or 0.2 mg) or IgG control. Systolic blood pressure (SBP) and cardiac function were detected by a tail-cuff and echocardiography. Cardiac remodeling was evaluated by histological staining. Adhesion and migration of bone marrow macrophages (BMMs) were evaluated in vitro. Our results indicated that VCAM-1 levels were increased in the serum of patients with heart failure (HF) and the hearts of Ang II-infused mice. Furthermore, Ang II-caused hypertension, cardiac dysfunction, hypertrophy, fibrosis, infiltration of VLA-4+ BMMs and oxidative stress were dose-dependently attenuated in mice administered VCAM-1 neutralizing antibody. In addition, blocking VCAM-1 markedly alleviated Ang II-induced BMMs adhesion and migration, therefore inhibited cardiomyocyte hypertrophy and fibroblast activation. In conclusion, the data reveal that blocking VCAM-1 ameliorates hypertensive cardiac remodeling by impeding VLA-4+ macrophage infiltration. Selective blockage of VCAM-1 may be a novel therapeutic strategy for hypertensive cardiac diseases.