Maize root exudates promote Bacillus sp. Za detoxification of diphenyl ether herbicides by enhancing colonization and biofilm formation.

Diphenyl ether herbicides are extensively utilized in agricultural systems, but their residues threaten the health of sensitive rotation crops. Functional microbial strains can degrade diphenyl ether herbicides in the rhizosphere of crops, facilitating the restoration of a healthy agricultural environment. However, the interplay between microorganisms and plants in diphenyl ether herbicides degradation remains unclear. Thus, the herbicide-degrading strain Bacillus sp. Za and the sensitive crop, maize, were employed to uncover the interaction mechanism. The degradation of diphenyl ether herbicides by strain Bacillus sp. Za was promoted by root exudates. The strain induced root exudates re-secretion in diphenyl ether herbicide-polluted maize. We further showed that root exudates enhanced the rhizosphere colonization and the biofilm biomass of strain Za, augmenting its capacity to degrade diphenyl ether herbicide. Root exudates regulated gene fliZ, pivotal in biofilm formation. Wild-type strain Za significantly reduced herbicide toxicity to maize compared to the ZaΔfliZ mutant. Moreover, root exudates promoted strain Za growth and chemotaxis, which was related to biofilm formation. This mutualistic relationship between the microorganisms and the plants demonstrates the significance of plant-microbe interactions in shaping diphenyl ether herbicide degradation in rhizosphere soils.

Persistent high sepsis-induced coagulopathy and sequential organ failure assessment scores can predict the 28-day mortality of patients with sepsis: A prospective study.

BACKGROUND: The performance of the sepsis-induced coagulopathy (SIC) and sequential organ failure assessment (SOFA) scores in predicting the prognoses of patients with sepsis has been validated. This study aimed to investigate the time course of SIC and SOFA scores and their association with outcomes in patients with sepsis. METHODS: This prospective study enrolled 209 patients with sepsis admitted to the emergency department. The SIC and SOFA scores of the patients were assessed on days 1, 2, and 4. Patients were categorized into survivor or non-survivor groups based on their 28-day survival. We conducted a generalized estimating equation analysis to evaluate the time course of SIC and SOFA scores and the corresponding differences between the two groups. The predictive value of SIC and SOFA scores at different time points for sepsis prognosis was evaluated. RESULTS: In the non-survivor group, SIC and SOFA scores gradually increased during the first 4 days (P < 0.05). In the survivor group, the SIC and SOFA scores on day 2 were significantly higher than those on day 1 (P < 0.05); however, they decreased on day 4, dropping below the levels observed on day 1 (P < 0.05). The non-survivors showed higher SIC scores on days 2 (P < 0.05) and 4 (P < 0.001) than the survivors, whereas no significant differences were found between the two groups on day 1 (P > 0.05). The performance of SIC scores on day 4 for predicting mortality was more accurate than that on day 2, with areas under the curve of 0.749 (95% confidence interval [CI]: 0.674-0.823), and 0.601 (95% CI: 0.524-0.679), respectively. The SIC scores demonstrated comparable predictive accuracy for 28-day mortality to the SOFA scores on days 2 and 4. Cox proportional hazards models indicated that SIC on day 4 (hazard ratio [HR] = 3.736; 95% CI: 2.025-6.891) was an independent risk factor for 28-day mortality. CONCLUSIONS: The time course of SIC and SOFA scores differed between surviving and non-surviving patients with sepsis, and persistent high SIC and SOFA scores can predict 28-day mortality.

Development of a cGMP-compliant process to manufacture donor-derived, CD45RA-depleted memory CD19-CAR T cells.

Autologous chimeric antigen receptor (CAR) T cells targeting the CD19 antigen have demonstrated a high complete response rate in relapsed/refractory B-cell malignancies. However, autologous CAR T cell therapy is not an option for all patients. Here we optimized conditions for clinical-grade manufacturing of allogeneic CD19-CAR T cells using CD45RA-depleted donor memory T cells (Tm) for a planned clinical trial. Tm were activated using the MACS GMP T Cell TransAct reagent and transduced in the presence of LentiBOOST with a clinical-grade lentiviral vector that encodes a 2nd generation CD19-CAR with a 41BB.zeta endodomain. Transduced T cells were transferred to a G-Rex cell culture device for expansion and harvested on day 7 or 8 for cryopreservation. The resulting CD19-CAR(Mem) T cells expanded on average 34.2-fold, and mean CAR expression was 45.5%. The majority of T cells were CD4+ and had a central memory or effector memory phenotype, and retained viral specificity. CD19-CAR(Mem) T cells recognized and killed CD19-positive target cells in vitro and had potent antitumor activity in an ALL xenograft model. Thus we have successfully developed a current good manufacturing practice-compliant process to manufacture donor-derived CD19-CAR(Mem) T cells. Our manufacturing process could be readily adapted for CAR(Mem) T cells targeting other antigens.

Circulating mid-regional proadrenomedullin is a predictor of mortality in patients with COVID-19: a systematic review and meta-analysis.

BACKGROUND: Although there is increasing understanding of the changes in the laboratory parameters of Coronavirus disease 2019 (COVID-19), the correlation between circulating Mid-regional Proadrenomedullin (MR-proADM) and mortality of patients with COVID-19 is not fully understood. In this study, we conducted a systematic review and meta-analysis to evaluate the prognostic value of MR-proADM in patients with COVID-19. METHODS: The PubMed, Embase, Web of Science, Cochrane Library, Wanfang, SinoMed and Chinese National Knowledge Infrastructure (CNKI) databases were searched from 1 January 2020 to 20 March 2022 for relevant literature. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used to assess quality bias, STATA was employed to pool the effect size by a random effects model, and potential publication bias and sensitivity analyses were performed. RESULTS: 14 studies comprising 1822 patients with COVID-19 met the inclusion criteria, there were 1145 (62.8%) males and 677 (31.2%) females, and the mean age was 63.8 ± 16.1 years. The concentration of MR-proADM was compared between the survivors and non-survivors in 9 studies and the difference was significant (P < 0.01), I2 = 46%. The combined sensitivity was 0.86 [0.73-0.92], and the combined specificity was 0.78 [0.68-0.86]. We drew the summary receiver operating characteristic (SROC) curve and calculated the area under curve (AUC) = 0.90 [0.87-0.92]. An increase of 1 nmol/L of MR-proADM was independently associated with a more than threefold increase in mortality (odds ratio (OR) 3.03, 95% confidence interval (CI) 2.26-4.06, I2 = 0.0%, P = 0.633). The predictive value of MR-proADM for mortality was better than many other biomarkers. CONCLUSION: MR-proADM had a very good predictive value for the poor prognosis of COVID-19 patients. Increased levels of MR-proADM were independently associated with mortality in COVID-19 patients and may allow a better risk stratification.

CgPG21 is involved in the degradation of the cell wall during the secretory cavity formation in Citrus grandis 'Tomentosa' fruits.

MAIN CONCLUSION: CgPG21 is mainly located in the cell wall, participates in the intercellular layer degradation of the cell wall during the formation of secretory cavity in the intercellular space-forming and lumen-expanding stages. The secretory cavity is a common structure in Citrus plants and is the main site for synthesis and accumulation of medicinal ingredients. The secretory cavity is formed in lysogenesis, when epithelial cells enter a process of programmed cell death. Pectinases are known to be involved in degradation of the cell wall during the cytolysis of secretory cavity cells, but the changes in cell structure, the dynamic characteristics of cell wall polysaccharides and the related genes regulating cell wall degradation are unclear. In this study, electron microscopy and cell wall polysaccharide-labeling techniques were used to study the main characteristics of cell wall degradation of the secreting cavity of Citrus grandis 'Tomentosa' fruits. At the same time, the full CDS length of the pectinase gene CgPG21 was cloned, encoding a protein composed of 480 amino acids. CgPG21 is mainly located in the cell wall, participates in the degradation of the intercellular layer of the cell wall during the development of the secretory cavity, and plays an important role in the formation of the secretory cavity in the intercellular space-forming and lumen-expanding stages. With the development of secretory cavity, the cell wall polysaccharides of epithelial cells gradually degrade. CgPG21 is mainly involved in the intercellular layer degradation.

Prediction of Effector Proteins from Trichoderma longibrachiatum Through Transcriptome Sequencing.

Trichoderma longibrachiatum SMF2 is an important biocontrol strain isolated by our group that can promote plant growth and induce plant disease resistance. To further study its biocontrol mechanism, the effector proteins secreted by T. longibrachiatum SMF2 were analyzed through bioinformatics and transcriptome sequencing. Overall, 478 secretory proteins produced by T. longibrachiatum were identified, of which 272 were upregulated after treatment with plants. Functional annotation showed that 36 secretory proteins were homologous with different groups of effectors from pathogenic microorganisms. Moreover, the quantitative PCR results of six putative effector proteins were consistent with those of transcriptome sequencing. Taken together, these findings indicate that the secretory proteins secreted by T. longibrachiatum SMF2 may act as effectors to facilitate its own growth and colonization or to induce plant immunity response.

Erector spinae muscle-based nomogram for predicting in-hospital mortality among older patients with severe community-acquired pneumonia.

BACKGROUND: No multivariable model incorporating erector spinae muscle (ESM) has been developed to predict clinical outcomes in older patients with severe community-acquired pneumonia (SCAP). This study aimed to construct a nomogram based on ESM to predict in-hospital mortality in patients with SCAP. METHODS: Patients aged ≥ 65 years with SCAP were enrolled in this prospective observational study. Least absolute selection and shrinkage operator and multivariable logistic regression analyses were used to identify risk factors for in-hospital mortality. A nomogram prediction model was constructed. The predictive performance was evaluated using the concordance index (C-index), calibration curve, net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis. RESULTS: A total of 490 patients were included, and the in-hospital mortality rate was 36.1%. The nomogram included the following independent risk factors: mean arterial pressure, peripheral capillary oxygen saturation, Glasgow Coma Scale score (GCS), lactate, lactate dehydrogenase, blood urea nitrogen levels, and ESM cross-sectional area. Incorporating ESM into the base model with other risk factors significantly improved the C-index from 0.803 (95% confidence interval [CI], 0.761-0.845) to 0.836 (95% CI, 0.798-0.873), and these improvements were confirmed by category-free NRI and IDI. The ESM-based nomogram demonstrated a high level of discrimination, good calibration, and overall net benefits for predicting in-hospital mortality compared with the combination of confusion, urea, respiratory rate, blood pressure, and age ≥ 65 years (CURB-65), Pneumonia Severity Index (PSI), Acute Physiology and Chronic Health Evaluation II (APACHEII), and Sequential Organ Failure Assessment (SOFA). CONCLUSIONS: The proposed ESM-based nomogram for predicting in-hospital mortality among older patients with SCAP may help physicians to promptly identify patients prone to adverse outcomes. TRIAL REGISTRATION: This study was registered at www.chictr.org.cn (registration number Chi CTR-2300070377).

Predictive nomogram for in-hospital mortality among older patients with intra-abdominal sepsis incorporating skeletal muscle mass.

BACKGROUND: Studies on prognostic factors for older patients with intra-abdominal sepsis are scarce, and the association between skeletal muscle mass and prognosis among such patients remains unclear. AIMS: To develop a nomogram to predict in-hospital mortality among older patients with intra-abdominal sepsis. METHODS: Older patients with intra-abdominal sepsis were prospectively recruited. Their demographics, clinical features, laboratory results, abdominal computed tomography-derived muscle mass, and in-hospital mortality were recorded. The predictors of mortality were selected via least absolute shrinkage and selection operator and multivariable logistic regression analyses, and a nomogram was developed. The nomogram was assessed and compared with Sequential Organ Failure Assessment score, Acute Physiology and Chronic Health Evaluation II score, and Simplified Acute Physiology Score II. RESULTS: In total, 464 patients were included, of whom 104 (22.4%) died. Six independent risk factors (skeletal muscle index, cognitive impairment, frailty, heart rate, red blood cell distribution width, and blood urea nitrogen) were incorporated into the nomogram. The Hosmer-Lemeshow goodness-of-fit test and calibration plot revealed a good consistency between the predicted and observed probabilities. The area under the receiver operating characteristic curve was 0.875 (95% confidence interval = 0.838-0.912), which was significantly higher than those of commonly used scoring systems. The decision curve analysis indicated the nomogram had good predictive performance. DISCUSSION: Our nomogram, which is predictive of in-hospital mortality among older patients with intra-abdominal sepsis, incorporates muscle mass, a factor that warrants consideration by clinicians. The model has a high prognostic ability and might be applied in clinical practice after external validation.

The enhanced mechanisms of Hansschlegelia zhihuaiae S113 degrading bensulfuron-methyl in maize rhizosphere by three organic acids in root exudates.

The residues of bensulfuron-methyl (BSM), a sulfonylurea herbicide, in soil have caused serious damage to the rotation of susceptible crops. Many studies have reported that the removal of BSM in soil was achieved by adding degrading bacteria. However, the mechanisms used by bacteria to degrade BSM in the crop rhizosphere remain unclear. In this study, a BSM-degrading bacterium, Hansschlegelia zhihuaiae S113, was applied to investigate the enhancement of effects mediated by organic acids during the bioremediation of BSM-contaminated maize rhizosphere soil. Organic acids, such as L-malic acid, tartaric acid, and fumaric acid, identified in maize root exudates, significantly stimulated the expression of cheA, which encoded the histidine kinase in strain S113 and contributed to the chemotactic response. This process accelerated the accumulation of strain S113 around the maize roots and promoted the colonization process on maize roots. The growth of strain S113 was significantly increased by L-malic acid but not tartaric acid or fumaric acid. After the S113 suspension was root-irrigated to BSM-contaminated soil, the density of strain S113 colonizing root surfaces and in rhizosphere soil reached 1.1 × 104 cells/g for roots and 4.9 × 104 cells/g in dry soil at 15 d, leading to 80.9% BSM degradation efficiency. The treatment with the addition of a mixture of S113 and L-malic acid completely degraded BSM in rhizosphere soil due to the strong attraction and growth promotion of strain S113 by L-malic acid, with a higher efficiency than that with the extra addition of fumaric acid (89.7%) or tartaric acid (87.0%). This paper revealed the enhancement effects of organic acids identified in root exudates for the in situ bioremediation of BSM-contaminated rhizosphere soil.

Comparison of performance of two large-scale vertical-flow constructed wetlands treating wastewater treatment plant tail-water: Contaminants removal and associated microbial community.

The removal efficiency of contaminants in large-scale integrated vertical-flow constructed wetland (IVCW) and vertical-flow constructed wetland (VCW) for wastewater treatment plant (WWTP) tail-water was evaluated, and the microbial community was also investigated in this study. The results for 14 months study period indicated that 40.05% chemical oxygen demand (COD), 45.47% ammonia nitrogen (NH4+-N), 62.55% total phosphorus (TP), 55.53% total nitrogen (TN) and 57.20% total suspended solids (TSS) average removal efficiencies were achieved in the IVCW. There was a poor performance of TN removal in the VCW, with an average removal efficiency of 38.13%. There was no significant seasonal difference in TP removal, and a strong positive correlation between influent TP load and removed load. The high-throughput sequencing analysis revealed that Proteobacteria, Planctomycetes, Bacteroidetes and Acidobacteria were dominant in nature and wetland systems. The relative abundance of nitrifying bacteria, denitrifying bacteria and anammox bacteria confirmed that nitrification, denitrification and anammox may be the main processes for nitrogen removal in the IVCW.

Disabled-2: a positive regulator of the early differentiation of myoblasts.

Dab2 is an adaptor protein and a tumor suppressor. Our previous study has found that Dab2 was expressed in early differentiating skeletal muscles in mouse embryos. In this study, we determined the role of Dab2 in the skeletal muscle differentiation using C2C12 myoblasts in vitro and Xenopus laevis embryos in vivo. The expression of Dab2 was increased in C2C12 myoblasts during the formation of myotubes in vitro. Knockdown of Dab2 expression in C2C12 myoblasts resulted in a reduction of myotube formation, whereas the myotube formation was enhanced upon overexpression of Dab2. Re-expression of Dab2 in C2C12 myoblasts with downregulated expression of Dab2 restored their capacity to form myotubes. Microarray profiling and subsequent network analyses on the 155 differentially expressed genes after Dab2 knockdown showed that Mef2c was an important myogenic transcription factor regulated by Dab2 through the p38 MAPK pathway. It was also involved in other pathways that are associated with muscular development and functions. In Xenopus embryos developed in vivo, XDab2 was expressed in the myotome of somites where various myogenic markers were also expressed. Knockdown of XDab2 expression with antisense morpholinos downregulated the expression of myogenic markers in somites. In conclusion, this study is the first to provide solid evidence to show that Dab2 is a positive regulator of the early myoblast differentiation.

Focal Adhesion Kinase and ß-Catenin Cooperate to Induce Hepatocellular Carcinoma.

There is an urgent need to understand the molecular signaling pathways that drive or mediate the development of hepatocellular carcinoma (HCC). The focal adhesion kinase (FAK) gene protein tyrosine kinase 2 is amplified in 16.4% of The Cancer Genome Atlas HCC specimens, and its amplification leads to increased FAK mRNA expression. It is not known whether the overexpression of FAK alone is sufficient to induce HCC or whether it must cooperate in some ways with other oncogenes. In this study, we found that 34.8% of human HCC samples with FAK amplification also show ß-catenin mutations, suggesting a co-occurrence of FAK overexpression and ß-catenin mutations in HCC. We overexpressed FAK alone, constitutively active forms of ß-catenin (CAT) alone, or a combination of FAK and CAT in the livers of C57/BL6 mice. We found that overexpression of both FAK and CAT, but neither FAK nor CAT alone, in mouse livers was sufficient to lead to tumorigenesis. We further demonstrated that FAK's kinase activity is required for FAK/CAT-induced tumorigenesis. Furthermore, we performed RNA-sequencing analysis to identify the genes/signaling pathways regulated by FAK, CAT, or FAK/CAT. We found that FAK overexpression dramatically enhances binding of ß-catenin to the promoter of androgen receptor (AR), which leads to increased expression of AR in mouse livers. Moreover, ASC-J9, an AR degradation enhancer, suppressed FAK/CAT-induced HCC formation. Conclusion: FAK overexpression and ß-catenin mutations often co-occur in human HCC tissues. Co-overexpression of FAK and CAT leads to HCC formation in mice through increased expression of AR; this mouse model may be useful for further studies of the molecular mechanisms in the pathogenesis of HCC and could lead to the identification of therapeutic targets.

Prophylactic dendritic cell vaccination controls pancreatic cancer growth in a mouse model.

PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths with high recurrence after surgery due to a paucity of effective post-surgical adjuvant treatments. DC vaccines can activate multiple anti-tumor immune responses but have not been explored for post-surgery PDAC recurrence. Intraperitoneal (IP) delivery may allow increased DC vaccine dosage and migration to lymph nodes. Here, we investigated the role of prophylactic DC vaccination controlling PDAC tumor growth with IP delivery as an administration route for DC vaccination. METHODS: DC vaccines were generated using ex vivo differentiation and maturation of bone marrow-derived precursors. Twenty mice were divided into four groups (n = 5) and treated with DC vaccines, unpulsed mature DCs, Panc02 lysates or no treatment. After tumor induction, mice underwent three magnetic resonance imaging scans to track tumor growth. Apparent diffusion coefficient (ADC), a quantitative magnetic resonance imaging measurement of tumor microstructure, was calculated. Survival was tracked. Tumor tissue was collected after death and stained with hematoxylin and eosin, Masson's trichrome, terminal deoxynucleotidyl transferase dUTP nick end labeling and anti-CD8 stains for histology. RESULTS: DC-vaccinated mice demonstrated stronger anti-tumor cytotoxicity compared with control groups on lactate dehydrogenase assay. DC vaccine mice also demonstrated decreased tumor volume, prolonged survival and increased ΔADC compared with control groups. On histology, the DC vaccine group had increased apoptosis, increased CD8+ T cells and decreased collagen. ΔADC negatively correlated with % collagen in tumor tissues. DISCUSSION: Prophylactic DC vaccination may inhibit PDAC tumor growth during recurrence and prolong survival. ΔADC may be a potential imaging biomarker that correlates with tumor histological features.

A novel esterase LanE from Edaphocola flava HME-24 and the enantioselective degradation mechanism of herbicide lactofen.

Lactofen is a chiral herbicide and widely used against broadleaf weeds in agriculture. As a pesticide, it is directly released to the environment, and easily caused contamination in soil and aquatic ecosystem. The enantioselective degradation of lactofen in the environment has been reported, but the molecular biological mechanism of this phenomenon is still unclear. In this study, strain Edaphocola flava HME-24 could degrade 96.7% of 50 mg L-1 lactofen within 72 h. Lactofen was initially hydrolyzed to desethyl lactofen and subsequently acifluorfen by strain HME-24. A novel gene lanE, involved in lactofen transformation, was obtained from Edaphocola flava HME-24. Gene lanE encoded a protein of 471 amino acids that contained the conserved GXSXG esterase motif and clustered into esterase subfamily V. LanE shared the highest identity with esterase EstD (Q9WYH1) from Thermotoga maritima MSB8 (29.14%). This esterase was also able to transform p-nitrophenyl esters (C4-C8), and the activity decreased when the carbon chain length increased. LanE showed enantioselectivity during the degradation of lactofen, diclofop-methyl, and quizalofop-ethyl, with a higher degradation efficiency of (S)-enantiomers than (R)-enantiomers. The three-dimensional structure of LanE was simulated, and molecular docking revealed that when the (S)-enantiomers of lactofen occupied the active sites, the distance between the ligand molecule and the coordination atom was shorter than that when the (R)-enantiomers occupied the active sites, which facilitated the formation of the transition state complex. The results in this study enhanced our understanding of the preferential catabolism of the (S)-enantiomers of lactofen on the molecular level and could illustrate the reported enantioselective degradation of lactofen in the environment.

Aspergillus flavus squalene synthase as an antifungal target: Expression, activity, and inhibition.

Invasive aspergillosis (IA) is a life-threatening disease impacting immunocompromised individuals. Standard treatments of IA, including polyenes and azoles, suffer from high toxicity and emerging resistance, leading to the need to develop new antifungal agents with novel mechanisms of action. Ergosterol biosynthesis is a classic target for antifungals, and squalene synthase (SQS) catalyzes the first committed step in ergosterol biosynthesis in Aspergillus spp. making SQS of interest in the context of antifungal development. Here, we cloned, expressed, purified and characterized SQS from the pathogen Aspergillus flavus (AfSQS), confirming that it produced squalene. To identify potential leads targeting AfSQS, we tested known squalene synthase inhibitors, zaragozic acid and the phosphonosulfonate BPH-652, finding that they were potent inhibitors. We then screened a library of 744 compounds from the National Cancer Institute (NCI) Diversity Set V for inhibition activity. 20 hits were identified and IC50 values were determined using dose-response curves. 14 compounds that interfered with the assay were excluded and the remaining 6 compounds were analyzed for drug-likeness, resulting in one compound, celastrol, which had an AfSQS IC50 value of 830 nM. Enzyme inhibition kinetics revealed that celastrol binds to AfSQS in a noncompetitive manner, but did not bind covalently. Since celastrol is also known to inhibit growth of the highly virulent Aspergillus fumigatus by inhibiting flavin-dependent monooxygenase siderophore A (SidA, under iron starvation conditions), it may be a promising multi-target lead for antifungal development.

Structural insight into a novel indole prenyltransferase in hapalindole-type alkaloid biosynthesis.

FamD1 is a novel CloQ/NphB-family indole prenyltransferase which involves in hapalindole-type alkaloid biosynthesis. Here the native FamD1 structure and three protein-ligand complexes are analyzed to investigate the molecular basis of substrate binding and catalysis. FamD1 adopts a typical ABBA architecture of aromatic prenyltransferase, in which the substrate-binding chamber is found in the central ß-barrel. The indole-containing acceptor substrate is bound adjacent to the prenyl donor. Based on the complex structures, a catalytic mechanism of FamD1 is proposed. Functional implications on the sister enzyme FamD2 are also discussed.

18F-FDG PET Biomarkers Help Detect Early Metabolic Response to Irreversible Electroporation and Predict Therapeutic Outcomes in a Rat Liver Tumor Model.

Purpose To test the hypothesis that biomarkers of fluorine 18 (18F) fluorodeoxyglucose (FDG) positron emission tomography (PET) can be used for the early detection of therapeutic response to irreversible electroporation (IRE) of liver tumor in a rodent liver tumor model. Materials and Methods The institutional animal care and use committee approved this study. Rats were inoculated with McA-RH7777 liver tumor cells in the left median and left lateral lobes. Tumors were allowed to grow for 7 days to reach a size typically at least 5 mm in longest diameter, as verified with magnetic resonance (MR) imaging. IRE electrodes were inserted, and eight 100-µsec, 2000-V pulses were applied to ablate the tumor tissue in the left median lobe. Tumor in the left lateral lobe served as a control in each animal. PET/computed tomography (CT) and MR imaging measurements were performed at baseline and 3 days after IRE for each animal. Additional MR imaging measurements were obtained 14 days after IRE. After 14-day follow-up MR imaging, rats were euthanized and tumors harvested for hematoxylin-eosin, CD34, and caspase-3 staining. Change in the maximum standardized uptake value (ΔSUVmax) was calculated 3 days after IRE. The maximum lesion diameter change (ΔDmax) was measured 14 days after IRE by using axial T2-weighted imaging. ΔSUVmax and ΔDmax were compared. The apoptosis index was calculated by using caspase-3-stained slices of apoptotic tumor cells. Pearson correlation coefficients were calculated to assess the relationship between ΔSUVmax at 3 days and ΔDmax (or apoptosis index) at 14 days after IRE treatment. Results ΔSUVmax, ΔDmax, and apoptosis index significantly differed between treated and untreated tumors (P < .001 for all). In treated tumors, there was a strong correlation between ΔSUVmax 3 days after IRE and ΔDmax 14 days after IRE (R = 0.66, P = .01) and between ΔSUVmax 3 days after IRE and apoptosis index 14 days after IRE (R = 0.57, P = .04). Conclusion 18F-FDG PET imaging biomarkers can be used for the early detection of therapeutic response to IRE treatment of liver tumors in a rodent model. © RSNA, 2017.

Three UDP-xylose transporters participate in xylan biosynthesis by conveying cytosolic UDP-xylose into the Golgi lumen in Arabidopsis.

UDP-xylose (UDP-Xyl) is synthesized by UDP-glucuronic acid decarboxylases, also termed UDP-Xyl synthases (UXSs). The Arabidopsis genome encodes six UXSs, which fall into two groups based upon their subcellular location: the Golgi lumen and the cytosol. The latter group appears to play an important role in xylan biosynthesis. Cytosolic UDP-Xyl is transported into the Golgi lumen by three UDP-Xyl transporters (UXT1, 2, and 3). However, while single mutants affected in the UDP-Xyl transporter 1 (UXT1) showed a substantial reduction in cell wall xylose content, a double mutant affected in UXT2 and UXT3 had no obvious effect on cell wall xylose deposition. This prompted us to further investigate redundancy among the members of the UXT family. Multiple uxt mutants were generated, including a triple mutant, which exhibited collapsed vessels and reduced cell wall thickness in interfascicular fiber cells. Monosaccharide composition, molecular weight, nuclear magnetic resonance, and immunolabeling studies demonstrated that both xylan biosynthesis (content) and fine structure were significantly affected in the uxt triple mutant, leading to phenotypes resembling those of the irx mutants. Pollination was also impaired in the uxt triple mutant, likely due to reduced filament growth and anther dehiscence caused by alterations in the composition of the cell walls. Moreover, analysis of the nucleotide sugar composition of the uxt mutants indicated that nucleotide sugar interconversion is influenced by the cytosolic UDP-Xyl pool within the cell. Taken together, our results underpin the physiological roles of the UXT family in xylan biosynthesis and provide novel insights into the nucleotide sugar metabolism and trafficking in plants.

Inhibition of SIRT2 suppresses hepatic fibrosis.

Liver fibrosis can progress to cirrhosis and result in serious complications of liver disease. The pathogenesis of liver fibrosis involves the activation of hepatic stellate cells (HSCs), the underlying mechanisms of which are not fully known. Emerging evidence suggests that the classic histone deacetylases play a role in liver fibrosis, but the role of another subfamily of histone deacetylases, the sirtuins, in the development of hepatic fibrosis remains unknown. In this study, we found that blocking the activity of sirtuin 2 (SIRT2) by using inhibitors or shRNAs significantly suppressed fibrogenic gene expression in HSCs. We further demonstrated that inhibition of SIRT2 results in the degradation of c-MYC, which is important for HSC activation. In addition, we discovered that inhibition of SIRT2 suppresses the phosphorylation of ERK, which is critical for the stabilization of c-MYC. Moreover, we found that Sirt2 deficiency attenuates the hepatic fibrosis induced by carbon tetrachloride (CCl4) and thioacetamide (TAA). Furthermore, we showed that SIRT2, p-ERK, and c-MYC proteins are all overexpressed in human hepatic fibrotic tissues. These data suggest a critical role for the SIRT2/ERK/c-MYC axis in promoting hepatic fibrogenesis. Inhibition of the SIRT2/ERK/c-MYC axis represents a novel strategy to prevent and to potentially treat liver fibrosis and cirrhosis.

Squalene synthase as a target for Chagas disease therapeutics.

Trypanosomatid parasites are the causative agents of many neglected tropical diseases and there is currently considerable interest in targeting endogenous sterol biosynthesis in these organisms as a route to the development of novel anti-infective drugs. Here, we report the first x-ray crystallographic structures of the enzyme squalene synthase (SQS) from a trypanosomatid parasite, Trypanosoma cruzi, the causative agent of Chagas disease. We obtained five structures of T. cruzi SQS and eight structures of human SQS with four classes of inhibitors: the substrate-analog S-thiolo-farnesyl diphosphate, the quinuclidines E5700 and ER119884, several lipophilic bisphosphonates, and the thiocyanate WC-9, with the structures of the two very potent quinuclidines suggesting strategies for selective inhibitor development. We also show that the lipophilic bisphosphonates have low nM activity against T. cruzi and inhibit endogenous sterol biosynthesis and that E5700 acts synergistically with the azole drug, posaconazole. The determination of the structures of trypanosomatid and human SQS enzymes with a diverse set of inhibitors active in cells provides insights into SQS inhibition, of interest in the context of the development of drugs against Chagas disease.