How do earthworms affect the pathway of sludge bio-stabilization via vermicomposting?

The synergy effects between earthworms and microorganisms promote nitrogen mineralization and enhance stabilization of organic matters in a vermicomposting system. However, the stabilization pathways of vermicomposting in the system remain unknown. The aim of this study was to investigate the effect of earthworms on the stabilization pathway and associated microbial population of waste activated sludge recycled by vermicomposting. The treatment of sludge with and without earthworms was conducted at 20 °C for 60 days. The trends in organic matter (OM), dissolved organic carbon (DOC), NH4+-N, electrical conductivity (EC), microbial biomass carbon (MBC), and dehydrogenase activity (DHA) were similar in both systems over time. At the end of the treatment, OM and DOC were significantly lower (p < 0.05), and EC, NH4+-N, and NO3--N were significantly higher (p < 0.05) in the vermicomposting group than in the control. Based on the statistical results of principal component analysis (PCA), it was proposed that the stabilization pathway in both treatment systems required a sequence of reactions characterized by the degradation of organic matter, accumulation of dissolved organic carbon, ammonification, and nitrification. Vermicomposting led to greater abundance and diversity (Shannon index) of 16S rDNA microbial species, but more even distribution in microbial community composition (Simpson index) than the control. However, the opposite performance for 18S rDNA microbes was observed. Vermicomposting enhanced the abundance of microorganisms involved in organic matter degradation and nitrification, facilitating the conversion of organic matter and favoring the nitrification. In short, the pathway of sludge bio-stabilization is not altered regardless of the addition of earthworms or not, which enables us to better understand vermicomposting process of sludge.

Two-Stage Hybrid Model for Efficiency Prediction of Centrifugal Pump.

Accurately predict the efficiency of centrifugal pumps at different rotational speeds is important but still intractable in practice. To enhance the prediction performance, this work proposes a hybrid modeling method by combining both the process data and knowledge of centrifugal pumps. First, according to the process knowledge of centrifugal pumps, the efficiency curve is divided into two stages. Then, the affinity law of pumps and a Gaussian process regression (GPR) model are explored and utilized to predict the efficiency at their suitable flow stages, respectively. Furthermore, a probability index is established through the prediction variance of a GPR model and Bayesian inference to select a suitable training set to improve the prediction accuracy. Experimental results show the superiority of the hybrid modeling method, compared with only using mechanism or data-driven models.

The SUMO E3 ligase activity of ORF45 determines KSHV lytic replication.

RSK1, an essential cellular kinase for Kaposi's sarcoma-associated herpesvirus (KSHV) replication, is highly phosphorylated and SUMOylated during KSHV lytic cycle, which determine the substrate phosphorylation and specificity of RSK1, respectively. However, the SUMO E3 ligase responsible for attaching SUMO to RSK1 has not yet been identified. By genome-wide screening, we found that KSHV ORF45 is necessary and sufficient to enhance RSK1 SUMOylation. Mechanistically, KSHV ORF45 binds to SUMOs via two classic SUMO-interacting motifs (SIMs) and functions as a SIM-dependent SUMO E3 ligase for RSK1. Mutations on these ORF45 SIMs resulted in much lower lytic gene expressions, viral DNA replication, and mature progeny virus production. Interestingly, KSHV ORF45 controls RSK1 SUMOylation and phosphorylation via two separated functional regions: SIMs and amino acid 17-90, respectively, which do not affect each other. Similar to KSHV ORF45, ORF45 of Rhesus Macaque Rhadinovirus has only one SIM and also increases RSK1 SUMOylation in a SIM-dependent manner, while other ORF45 homologues do not have this function. Our work characterized ORF45 as a novel virus encoded SUMO E3 ligase, which is required for ORF45-RSK1 axis-mediated KSHV lytic gene expression.

Analysis of crystal structure of Arabidopsis MPK6 and generation of its mutants with higher activity.

Mitogen-activated protein kinase (MAPK) cascades, which are the highly conserved signalling modules in eukaryotic organisms, have been shown to play important roles in regulating growth, development, and stress responses. The structures of various MAPKs from yeast and animal have been solved, and structure-based mutants were generated for their function analyses, however, the structures of plant MAPKs remain unsolved. Here, we report the crystal structure of Arabidopsis MPK6 at a 3.0 Å resolution. Although MPK6 is topologically similar to ERK2 and p38, the structures of the glycine-rich loop, MAPK insert, substrate binding sites, and L16 loop in MPK6 show notable differences from those of ERK2 and p38. Based on the structural comparison, we constructed MPK6 mutants and analyzed their kinase activity both in vitro and in planta. MPK6(F364L) and MPK6(F368L) mutants, in which Phe364 and Phe368 in the L16 loop were changed to Leu, respectively, acquired higher intrinsic kinase activity and retained the normal MAPKK activation property. The expression of MPK6 mutants with basal activity is sufficient to induce camalexin biosynthesis; however, to induce ethylene and leaf senescence, the expression of MPK6 mutants with higher activity is required. The results suggest that these mutants can be used to analyze the specific biological functions of MPK6.

Further Studies on Structure-Cardiac Activity Relationships of Diterpenoid Alkaloids.

The cardiac effect of thirty-eight diterpenoid alkaloids was evaluated on the isolated bullfrog heart model. Among them, twelve compounds exhibited appreciable cardiac activity, with compounds 3 and 35 being more active than the reference drug lanatoside. The structure-cardiac activity relationships of the diterpenoid alkaloids were summarized based on our present and previous studies [2]: i) 1α-OMe or 1α-OH, 8-OH, 14-OH, and NH (or NMe) are key structural features important for the cardiac effect of the aconitine-type C19-diterpenoid alkaloids without any esters. C18-diterpenoid alkaloids, lycoctonine-type C19-diterpenoid alkaloids, and the veatchine- and denudatine-type C20-diterpenoid alkaloids did not show any cardiac activity; ii) the presence of 3α-OH is beneficial to the cardiac activity; iii) the effect on the cardiac action of 6α-OMe, 13-OH, 15α-OH, and 16-demethoxy or a double bond between C-15 and C-16 depends on the substituent pattern on the nitrogen atom.

Ring A conformation of aconine and pseudaconine in CDCl3.

On the basis of intensive interpretation of the 1H NMR spectroscopic data, the ring A conformation of aconine (1) was speculated as twist boat in CDCl3, and as chair or twist boat in acetone-d6 and pyridine-d5. The ring A of pseudaconine (2) adopts the chair conformation in CDCl3, acetone-d6, and pyridine-ds. Accordingly, the boat conformation of ring A in these two diterpenoid alkaloids in CDCl3 reported in the literature [1] should be revised. The difference in 13C NMR data for the same compound (1 or 2) in two different solvents (CDCl3, pyridine-d5) can be attributed to solvent effects.

Foreign body removed by the 'Fire and Ice Technique': A case report.

With the introduction of flexible bronchoscopies, several techniques and accessories have been available for the removal of foreign bodies (FB). However, in some cases, using conventional techniques are inappropriate and fail to remove the FB. Here we report a case of a 33-year-old male with 19 years foreign body aspiration history. A successfully removal of the ingrown FB was achieved by means of an argon plasma coagulation and a flexible cryoprobe.

Tripartite motif-containing protein 28 is a small ubiquitin-related modifier E3 ligase and negative regulator of IFN regulatory factor 7.

IFN regulatory factor 7 (IRF7) is a potent transcription factor of type I IFNs and IFN-stimulated genes and is known as the master regulator of type I IFN-dependent immune responses. Because excessive responses could harm the host, IRF7 itself is delicately regulated at the transcriptional, translational, and posttranslational levels. Modification of IRF7 by small ubiquitin-related modifiers (SUMOs) has been shown to regulate IFN expression and antiviral responses negatively, but the specific E3 ligase needed for IRF7 SUMOylation has remained unknown. As reported in this article, we have identified the tripartite motif-containing protein 28 (TRIM28) as a binding partner of IRF7. We have demonstrated that TRIM28 also interacts with the SUMO E2 enzyme and increases SUMOylation of IRF7 both in vivo and in vitro, suggesting it acts as a SUMO E3 ligase of IRF7. Unlike the common SUMO E3 ligase, protein inhibitor of activated STAT1, the E3 activity of TRIM28 is specific to IRF7, because it has little effect on IRF7's close relative IRF3. TRIM28 is therefore, so far as we know, the first IRF7-specific SUMO E3 reported. TRIM28-mediated SUMOylation of IRF7 is increased during viral infection, and SUMOylation of transcription factors usually results in transcriptional repression. Overexpression of TRIM28 therefore inhibits IRF7 transactivation activity, whereas knockdown of TRIM28 has the opposite effect and potentiates IFN production and antiviral responses. Collectively, our results suggest that TRIM28 is a specific SUMO E3 ligase and negative regulator of IRF7.

Negative regulation of IRF7 activation by activating transcription factor 4 suggests a cross-regulation between the IFN responses and the cellular integrated stress responses.

Cells react to viral infection by exhibiting IFN-based innate immune responses and integrated stress responses, but little is known about the interrelationships between the two. In this study, we report a linkage between these two host-protective cellular mechanisms. We found that IFN regulatory factor (IRF)7, the master regulator of type I IFN gene expression, interacts with activating transcription factor (ATF)4, a key component of the integrated stress responses whose translation is induced by viral infection and various stresses. We have demonstrated that IRF7 upregulates ATF4 activity and expression, whereas ATF4 in return inhibits IRF7 activation, suggesting a cross-regulation between the IFN response and the cellular integrated stress response that controls host innate immune defense against viral infection.

The Gemin5 protein of the SMN complex identifies snRNAs.

The survival of motor neurons protein (SMN) is part of a large complex that contains six other proteins, Gemins2-7. The SMN complex assembles the heptameric Sm protein core on small nuclear RNAs (snRNAs) and plays a critical role in the biogenesis of snRNPs, the major and essential components of mRNA splicing in eukaryotes. For its function, the SMN complex binds Sm proteins and snRNAs, which it distinguishes from other RNAs by specific features they contain. We show here that Gemin5, a 170 kDa WD-repeat protein, is the snRNA binding protein of the SMN complex. Gemin5 binds directly and specifically to the unique features, including the Sm site, of snRNAs. Reduction of Gemin5 results in reduced capacity of the SMN complex to bind snRNAs and to assemble Sm cores. Gemin5 therefore functions as the factor that allows the SMN complex to distinguish snRNAs from other cellular RNAs for snRNP biogenesis.

Bond strength of silicone to polyurethane following immersion of silicone in cleaning solutions.

STATEMENT OF PROBLEM: The use of polyurethane liners beneath silicone facial prostheses is recommended to improve the effectiveness of water-based adhesives, reduce bacterial colonization, and allow very thin margins. Patients using silicone prostheses with a polyurethane lining often observe different degrees of debonding which may lead to failure of the prosthesis. Aggressive cleaning may be associated with debonding of the silicone to polyurethane. PURPOSE: The purpose of this investigation was to determine the effect on bond strength of soaking specimens of silicone to polyurethane in hot or room-temperature soapy water. MATERIAL AND METHODS: Specimens of silicone to primed polyurethane were divided into 3 groups of 16 specimens for testing: control (no soak), room-temperature soapy water soak, and hot soapy water soak. The soaked specimens were placed in soapy water at different temperatures for 1825 minutes to simulate 1 year of a 5 min/day cleaning cycle. One examiner performed the assessment of T-peel strength (N/mm) for all specimens. Each specimen was attached to an adhesive testing machine and separated in tension at the crosshead speed of 25.4 mm/min. Data were analyzed with a 1-way ANOVA followed by post hoc pairwise testing using the Tukey test (alpha=.05). RESULTS: A significant difference in bonding strength between the 3 groups was found (P<.001), with post hoc tests indicating that the control group bonding strength (6.06 +/- 1.84 N/mm) was significantly higher than both room-temperature water soapy soak (3.93 +/- 1.84 N/mm; P=.005) and the hot soapy water soak group values (2.49 +/- 1.75 N/mm; P<.001). However, there was no significant difference found between the hot and room-temperature soapy soak values. CONCLUSION: Within the limitations of this study, soaking in hot or room-temperature soapy water produced a significant reduction of bond strength of silicone to polyurethane.

DNA vaccines against the human papillomavirus type 16 E6 or E7 oncoproteins.

DNA vaccines expressing the E6 or E7 oncoproteins of human papilloma virus type 16 (HPV-16) in either their wild-type form or fused to sequences that affect intracellular trafficking were tested for induction of protective immunity against tumor cell challenge in two models based on BALB/c and C57Bl/6 mice. The DNA vaccines to E7 gave uniformly disappointing results, while the DNA vaccine that expressed E6 linked to a viral leader sequence protected BALB/c mice against tumor cell challenge given before or after vaccination. The efficacy of this vaccine could be enhanced by a DNA vector prime/viral vector boost regimen. In contrast, priming of mice with the DNA vaccines to E7 reduced the efficacy of a viral vector expressing the same antigen.