Fluorescent microsphere probe for rapid qualitative and quantitative detection of trypsin activity

Current technologies still face a big challenge to achieve simultaneous rapid qualitative and quantitative detection of trypsin. In our present study, we developed a simple and effective strategy to sensitively, qualitatively and quantitatively analyze the activity of trypsin using a fluorescent polystyrene (PS) microsphere probe. PS spheres were first functionalized by the surface coating of polyethylene glycol (PEG), which could significantly decrease the possibility of nonspecific physical adsorption of the fluorescein isothiocyanate isomer-modified peptide (peptide-FITC). Then, the obtained PS-PEG spheres were chemically interacted with peptide-FITC, which were then employed to monitor the real-time activity of trypsin. The peptide used in our work contained rich lysine and arginine residues, which were the recognition sites of trypsin. When trypsin interacted with the PS-FITC-peptide microspheres, the peptide-FITC rapidly decomposed into free small fragments in solution, resulting in a gradual decrease in the fluorescence of the PS spheres. By taking advantage of the fluorescence changes using confocal microscopy imaging and fluorescence spectrum intensity, it is easy to achieve the qualitative and quantitative detection of trypsin, with a highly sensitive detection limit as low as 0.5 ng mL^-1 and high selectivity. Thus, the designed fluorescent PS microsphere probe would be very promising in various applications such as food safety inspection, personal healthcare and on-site environmental monitoring.

Recruitment of Vps34 PI3K and enrichment of PI3P phosphoinositide in the viral replication compartment is crucial for replication of a positive-strand RNA virus

Tombusviruses depend on subversions of multiple host factors and retarget cellular pathways to support viral replication. In this work, we demonstrate that tomato bushy stunt virus (TBSV) and the closely-related carnation Italian ringspot virus (CIRV) recruit the cellular Vps34 phosphatidylinositol 3-kinase (PI3K) into the large viral replication compartment. The kinase function of Vps34 is critical for TBSV replication, suggesting that PI(3)P phosphoinositide is utilized by TBSV for building of the replication compartment. We also observed increased expression of Vps34 and the higher abundance of PI(3)P in the presence of the tombusviral replication proteins, which likely leads to more efficient tombusvirus replication. Accordingly, overexpression of PI(3)P phosphatase in yeast or plants inhibited TBSV replication on the peroxisomal membranes and CIRV replication on the mitochondrial membranes. Moreover, the purified PI(3)P phosphatase reduced TBSV replicase assembly in a cell-free system. Detection of PI(3)P with antibody or a bioprobe revealed the enrichment of PI(3)P in the replication compartment. Vps34 is directly recruited into the replication compartment through interaction with p33 replication protein. Gene deletion analysis in surrogate yeast host unraveled that TBSV replication requires the vesicle transport function of Vps34. In the absence of Vps34, TBSV cannot efficiently recruit the Rab5-positive early endosomes, which provide PE-rich membranes for membrane biogenesis of the TBSV replication compartment. We found that Vps34 and PI(3)P needed for the stability of the p33 replication protein, which is degraded by the 26S proteasome when PI(3)P abundance was decreased by an inhibitor of Vps34. In summary, Vps34 and PI(3)P are needed for providing the optimal microenvironment for the replication of the peroxisomal TBSV and the mitochondrial CIRV.

Replication of RNA viruses infecting various eukaryotic organisms is the central step in the infection process that leads to generation of progeny viruses. The replication process requires the assembly of numerous viral replicase complexes within the large replication compartment, whose formation is not well understood. Using tombusviruses and the model host yeast, the authors discovered that a highly conserved cellular lipid kinase, Vps34 phosphatidylinositol 3-kinase (PI3K), is critical for the formation of the viral replication compartment. Expression of PI3K mutants and the PI(3)P phosphatase revealed that the PI(3)P phosphoinositide produced by Vps34 is crucial for tombusvirus replication. Tombusviruses co-opt Vps34 through interaction with the viral replication protein into the replication compartment. In vitro reconstitution of the tombusvirus replicase revealed the need for Vps34 and PI(3)P for the full-activity of the viral replicase. Chemical inhibition of Vps34 in yeast or plants showed that PI(3)P is important for the replication of several plant viruses within the Tombusviridae family and the insect-infecting Nodamuravirus. These results open up the possibility that the cellular Vps34 PI3K could be a target for new antiviral strategies.

Self-Propagating Synthesis and Characterization Studies of Gd-Bearing Hf-Zirconolite Ceramic Waste Forms

Synroc is recognized as the second-generation waste matrice for nuclear waste disposal. Zirconolite is one of the most durable Synroc minerals. In this study, Gd and Hf were selected as the surrogates of trivalent and tetravalent actinide nuclides. Gd-bearing Hf-zirconolite (Ca_1-xHf_1-xGd_2xTi₂O₇) ceramic waste forms were rapidly synthesized from a self-propagating technique using CuO as the oxidant. The results indicate that Gd can concurrently replace the Ca and Hf sites. However, Gd₂O₃ could not completely be incorporated into the lattice structure of zirconolite when the x value is higher than 0.8. The aqueous durability of selected Gd-Hf codoped sample (Hf-Gd-0.6) was tested, where the 42 days normalized leaching rates (LR_i) of Ca, Cu, Gd and Hf are measured to be 1.57, 0.13, 4.72 × 10^-7 and 1.59 × 10^-8 g·m^-2·d^-1.

AS1411 aptamer-modified theranostic liposomes co-encapsulating manganese oxide nano-contrast agent and paclitaxel for MRI and therapy of cancer

With the advantages and development of MRI nano-contrast agents (CAs), increasing number of MRI-based theranostic nanoparticles have emerged. Liposome, as a biosafe nanocarrier has been used phase III trial for cancer treatment. In this study, liposome was employed as a nanocarrier to co-encapsulate MRI nano-contrast agent poly(ethylene glycol)-grafted manganese oxide (PEG-MnO) and anticancer drug paclitaxel (PTX) for the fabrication of a novel theranostic nanocomplex. After being further modified with AS1411 aptamer, the obtained nanoprobe AS1411-liposome-PEG-MnO-PTX displayed the potential of simultaneous MRI diagnosis and therapy of renal carcinoma in vitro and in vivo. It was found that compared with PEG-MnO nano-CA, liposome-PEG-MnO and AS1411-liposome-PEG-MnO presented a stronger MR contrast enhancement effect in the tumor and longer retention time in the tumor region. More importantly, the introduction of AS1411 aptamer further enhanced the MRI effect and the tumor growth inhibition effect, showing its potential use as a theranostic nanoprobe for renal carcinoma.

AS1411 aptamer modified theranostic liposomes co-encapsulating manganese oxide nano-contrast agent and paclitaxel for MRI and therapy of cancer was realized.

A Pd-catalyzed asymmetric allylic substitution cascade via an asymmetric desymmetrization for the synthesis of bicyclic dihydrofurans

Chiral bicyclic dihydrofurans bearing two vicinal carbon stereocenters have been synthesized in high yields and with up to 97% ee via a Pd-catalyzed asymmetric allylic substitution cascade and an asymmetric desymmetrization process.

Correlations of breast cancer FHIT gene with the incidence and prognosis of breast cancer

PURPOSE

The study aimed to investigate the expression level of fragile histidine triad (FHIT) in breast cancer and analyze its prognostic value.

METHODS

148 patients admitted and definitely diagnosed with breast cancer in Daqing Long Nan Hospital from January 2011 to January 2013 were collected. Breast cancer, cancer-adjacent and normal tissues of the patients were taken and immunohistochemically stained, and the relationship between FHIT and p16 expressions were analyzed at the gene and protein levels. In addition, clinical data of patients were collected, and analyzed if there was a correlation between FHIT and p16 expressions.

RESULTS

FHIT and p16 were strongly positive in cancer-adjacent tissues and normal tissues but weakly positive in breast cancer tissues, with statistically significant differences in FHIT and p16 expressions (p<0.05). FHIT expression was positively correlated with p16 expression in breast cancer tissues (Spearman's correlation coefficient r=0.352, p=0.026). There were correlations of FHIT with TNM staging of breast cancer, grade of differentiation, lymph node metastasis and formation of portal vein tumor thrombi (p<0.05 in all comparisons). P16 was correlated with tumor size and grade of differentiation (p<0.05 in all comparisons). Expressions of both FHIT and p16 genes and proteins in breast cancer tissues were remarkably lower than those in cancer-adjacent and normal tissues (p<0.05 in all comparisons). Log-rank analysis showed that the 5-year overall survival of patients with FHIT+p16+expressions was significantly longer than that of patients with other phenotypes of expressions (p<0.0001).

CONCLUSION

The tumor suppressor gene FHIT is lowly expressed in breast cancer tissues and positively associated with the expression of the multi-tumor suppressor gene p16. The 5-year overall prognosis of patients with FHIT+p16+ expressions was better and can be used as one of the prognostic indicators for breast cancer patients.

Activity of coumarin against Candida albicans biofilms

OBJECTIVE

The aim of this study was to investigate the antibiofilm activity of coumarin against Candida albicans.

METHODS

The efficacy of coumarin against biofilm formation and the mature biofilm of C. albicans was quantified by crystal violet (CV) staining and the 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) reduction assay. The effect of coumarin on C. albicans adhesion was assessed on polystyrene plates and by using the cell surface hydrophobicity (CSH) assay. The morphological transition of C. albicans was conducted in two types of hyphae-inducing media at 37°C. The expression of hypha/biofilm-related genes was evaluated using qRT-PCR analysis. A rescue experiment involving addition of exogenous cyclic adenosine monophosphate (cAMP) was performed to investigate the involvement of cAMP in the yeast-to-hyphae transition. A C. albicans-infected Caenorhabditis elegans model was used to test the anti-virulence efficacy of coumarin.

RESULTS

Treatment with coumarin strongly affected the capacity of C. albicans to form biofilm and significantly impaired the preformed mature biofilm. The addition of coumarin notably inhibited C. albicans adhesion, CSH, and filamentation. The expression of some adhesion- and hypha-related genes, including HWP1, HYR1, ECE1, and ALS3, was remarkably down-regulated upon exposure to coumarin. Supplementation with cAMP partly rescued the coumarin-induced defects in hyphal development. Finally, coumarin prolonged survival in C. albicans-infected nematodes.

CONCLUSION

Coumarin inhibited C. albicans biofilm, which was associated with attenuated adhesion and hyphal growth.

[Application of laparoscopy-assisted total gastrectomy in elderly patients ≥65 years with gastric cancer]

OBJECTIVE

To evaluate the safety and feasibility of laparoscopy-assisted total gastrectomy in gastric cancer patients over 65 years old.

METHODS

Clinical, pathological and follow-up data of 188 gastric cancer patients who underwent laparoscopy-assisted total gastrectomy at Department IV of Gastrointestinal Cancer Center, Peking University Cancer Hospital, from April 2009 to December 2016 were collected for a retrospective cohort study.

INCLUSION CRITERIA

ECOG performance score 0-1; preoperative gastroscopy discovered gastric masses, and pathological biopsy confirmed adenocarcinoma; distant metastases were excluded by image examination; preoperative cardiopulmonary function was normal; preoperative blood routine test, liver and renal function, and coagulation function were normal; laparoscopy-assisted total gastrectomy was performed.

EXCLUSION CRITERIA

intraoperative laparoscopic exploration indicated abdominal and/or pelvic peritoneal metastasis; free cancer cells in peritoneal cavity; conversion to laparotomy during laparoscopic surgery. Patients were divided by age into 2 groups, ≥ 65 years old group(59 cases) and < 65 years old group (129 cases). The perioperative conditions and postoperative complications between two groups were compared, and the high risk factors of postoperative complications in patients over 65 years old were analyzed.

RESULTS

All the patients were operated by the same operation team. The incidence of comorbidities was 44.1%(26/59) in the ≥ 65 years old group, which was significantly higher than 20.2% (26/129) in the < 65 years old group (χ²=11.570, P=0.001). The incidence of cardia/fundus cancer was 64.4%(38/59) in the ≥ 65 years old group, which was also significantly higher than 40.3% (52/129) in the < 65 years old group (χ²=16.625, P=0.001). The number of retrieved lymph nodes in the ≥65 years old group was significantly lower than that in the < 65 years old group (28.9±10.7 vs. 36.1±15.4, t=3.271, P=0.001). The total morbidity of complications was 13.8%(21/188) and the mortality within 30 days after operation was 1.6%(3/188). The morbidity of postoperative complications and the mortality within 30 days after operation were 20.3%(12/59) and 3.4%(2/59,respectively) in the ≥ 65 years old group, which were slightly higher than those in the <65 years old group [10.9%(14/129) and 0.8%(1/129)], without significant difference(both P>0.05). Multivariate logistic regression analysis showed that preoperative comorbidities(OR=0.223, 95%CI:0.053 to 0.944, P=0.041) was an independent risk factor for postoperative complications in patients aged ≥ 65 years old undergoing laparoscopy-assisted total gastrectomy. The median survival time was 21.3 months and the overall 5-year survival rate was 50.0%. The 5-year survival rate was 45.5% and 57.5% in patients aged ≥ 65 and < 65 years, respectively, and there was no significant difference(P=0.205).

CONCLUSIONS

Laparoscopy-assisted total gastrectomy is safe and effective in the treatment of gastric cancer patients ≥ 65 years old. Age is not a contraindication of laparoscopy-assisted total gastrectomy.

Dispersion-guided ablation in conjunction with circumferential pulmonary vein isolation is superior to stepwise ablation approach for persistent atrial fibrillation

BACKGROUND

Due to the lack of optimal ablation strategy, the success rate of persistent atrial fibrillation (AF) is still low. We hypothesize that a strategy that targeting pulmonary triggers and dispersion areas in atria improves prognosis of persistent AF.

METHODS

We prospectively enrolled 142 persistent AF patients admitted for catheter ablation. These patients were randomly assigned in a 1:1 ratio to ablation with circumferential pulmonary vein isolation (CPVI) + ablation of electrogram dispersion areas (71 patients, group A) or stepwise ablation strategy (71 patients, group B).

RESULTS

Procedural time and fluoroscopy time did not differ between group A and group B (204.6 ± 26.9 min vs 207.8 ± 26.3 min and 7.3 ± 1.3 min vs 7.1 ± 1.3 min, respectively, P > 0.05), however, radiofrequency delivery time in group A was significantly shorter than that in group B (70 ± 7.2 min vs 83.2 ± 9.1 min, P < 0.001). In total, 265 electrogram dispersion areas were identified in 67 patients, and the most prominent areas were roof, bottom, and inferoposterior wall. The rates of acute AF endpoint (including AF termination and AFCL elongation >30 ms) and termination in group A were significantly higher than that in group B (97.2% vs. 71.8% and 70.4% vs. 15.5%, respectively, P < 0.001). During a follow-up period of 204 ± 67 days, both AF-free and AF/AT-free survival in group A were significantly higher than that in group B (P = 0.012 and P = 0.014, respectively).

CONCLUSION

Dispersion-guided ablation in conjunction with CPVI is efficient, personalized, and accurate for persistent AF.

Histological analysis of human pancreatic carcinoma following irreversible electroporation in a nude mouse model

AIM

To determine changes in the morphology and function of pancreatic cancer cells after irreversible electroporation (IRE) treatment, and to explore the clinical significance of IRE treatment for pancreatic cancer providing an experimental basis for the clinical application of IRE treatment.

METHODS

IRE was carried out in an athymic nude mouse model of pancreatic carcinoma generated with human pancreatic cancer cells 1. In therapy groups, IRE electrodes were inserted with 90 pulses per second at 800 V/cm applied to ablate the targeted tumor tissues. Histological assessment of the affected tissue was performed by hematoxylin and eosin staining (HE). Quantification of cell proliferation and apoptosis was performed by evaluating Ki67 and caspase-3 levels, respectively. Flow cytometry was used to assess cell apoptosis. Ultrasound imaging was carried out to evaluate IRE treatment results. Pathological correlation studies showed IRE is effective for the targeted ablation of pancreatic tumors in an orthotopic mouse model.

RESULTS

IRE was efficacious in removing tumors in the orthotopic mouse model. The IRE-ablated zone displays characteristics of nude mouse models at different time-points as assessed by hematoxylin and eosin staining. Immunohistochemical analysis of samples from the pancreatic cancer models showed significantly enhanced caspase-3 cleavage and Ki67. Flow cytometry data corroborated the above findings that apoptosis in tumor cells was observed immediately on the first postoperative day, and with time the middle and late stages of apoptosis were observed. For ultrasound imaging studies, the IRE ablation zone became a hyperechoic area due to increasing inflammatory and immunologic cellular contents.

CONCLUSION

IRE is a promising new approach for pancreatic cancer, with many potential advantages over conventional ablation techniques.

Diagnostic accuracy of magnetic resonance angiography for Budd-Chiari syndrome: A meta-analysis

In recent years, the role of magnetic resonance angiography (MRA) in the diagnosis of Budd-Chiari Syndrome (BCS) has been the focus of various clinical studies. The purpose of the present study was to perform a meta-analysis of the diagnostic performance of MRA in patients with BCS by using digital subtraction angiography as a reference method. The search strategy for relevant research articles was based on the Cochrane Handbook for Systematic Reviews, and literature databases (including PubMed, Medline and China National Knowledge Infrastructure) and reference lists of retrieved studies published from 2000 to 2016 were searched. The Quality Assessment of Diagnostic Accuracy Studies tool was used to assess the methodological quality of these research studies by two reviewers independently. Summary estimates of the sensitivity, specificity, positive/negative likelihood ratio (LR+/-), diagnostic odds ratio (DOR) and the summary receiver operating characteristic (SROC) curve of MRA in identifying BCS were obtained. The pooled MRA estimates had a sensitivity of 97.6% [95% confidence interval (CI), 95.1-99.0%], a specificity of 70.7% (95% CI, 54.5-83.9%), an LR+ of 3.163 (95% CI, 2.03-4.94) and an LR- of 0.045 (95% CI, 0.02-0.09). The overall DOR was 94.053 (95% CI, 32.71-270.41). The area under the SROC curve was 0.972. In conclusion, MRA is an accurate modality for evaluating BCS.

Further Understanding of Degradation Pathways of Microcystin-LR by an Indigenous Sphingopyxis sp. in Environmentally Relevant Pollution Concentrations

Microcystin-LR (MC-LR) is the most widely distributed microcystin (MC) that is hazardous to environmental safety and public health, due to high toxicity. Microbial degradation is regarded as an effective and environment-friendly method to remove it, however, the performance of MC-degrading bacteria in environmentally relevant pollution concentrations of MC-LR and the degradation pathways remain unclear. In this study, one autochthonous bacterium, Sphingopyxis sp. m6 which exhibited high MC-LR degradation ability, was isolated from Lake Taihu, and the degrading characteristics in environmentally relevant pollution concentrations were demonstrated. In addition, degradation products were identified by utilizing the full scan mode of UPLC-MS/MS. The data illustrated that strain m6 could decompose MC-LR (1–50 μg/L) completely within 4 h. The degradation rates were significantly affected by temperatures, pH and MC-LR concentrations. Moreover, except for the typical degradation products of MC-LR (linearized MC-LR, tetrapeptide, and Adda), there were 8 different products identified, namely, three tripeptides (Adda-Glu-Mdha, Glu-Mdha-Ala, and Leu-MeAsp-Arg), three dipeptides (Glu-Mdha, Mdha-Ala, and MeAsp-Arg) and two amino acids (Leu, and Arg). To our knowledge, this is the first report of Mdha-Ala, MeAsp-Arg, and Leu as MC-LR metabolites. This study expanded microbial degradation pathways of MC-LR, which lays a foundation for exploring degradation mechanisms and eliminating the pollution of microcystins (MCs).

SBLC: a hybrid model for disease named entity recognition based on semantic bidirectional LSTMs and conditional random fields

Background

Disease named entity recognition (NER) is a fundamental step in information processing of medical texts. However, disease NER involves complex issues such as descriptive modifiers in actual practice. The accurate identification of disease NER is a still an open and essential research problem in medical information extraction and text mining tasks.

Methods

A hybrid model named Semantics Bidirectional LSTM and CRF (SBLC) for disease named entity recognition task is proposed. The model leverages word embeddings, Bidirectional Long Short Term Memory networks and Conditional Random Fields. A publically available NCBI disease dataset is applied to evaluate the model through comparing with nine state-of-the-art baseline methods including cTAKES, MetaMap, DNorm, C-Bi-LSTM-CRF, TaggerOne and DNER.

Results

The results show that the SBLC model achieves an F1 score of 0.862 and outperforms the other methods. In addition, the model does not rely on external domain dictionaries, thus it can be more conveniently applied in many aspects of medical text processing.

Conclusions

According to performance comparison, the proposed SBLC model achieved the best performance, demonstrating its effectiveness in disease named entity recognition.

[A brief textual research on Mei shi fang (Prescriptions of Master Mei) and Yi men fang (Prescriptions of Medical Professionals)]

Mei shi fang (Prescriptions of Master Mei) cited in Zheng lei ben cao (Classified Syndromes Materia Medica) and Yi men fang (Prescriptions of Medical Professionals) cited in Yi xin fang (Ishinpo) are actually the same book with different titles, which is actually called Yi men mi lu (Secret Records of Medical Professionals) with 5 volumes or the 5-volume Mei chong xian fang (Prescriptions of Mei Chongxian) approximately compiled during the years of Zhenyuan to Yuanhe reigns of the Tang Dynasty (785-820) written by Mei Chongxian, a Tang taoist. Mei Chongxian and Mei Biao, the author of Shi yao er ya (Dictionary of Mineral Medicines), might probably be the same person. According to the citations of Yi xin fang and Zheng lei ben cao, Yi men mi lu should be a comprehensive medical book including theories, methods, prescriptions and medications, recorded classical prescriptions of predecessors extensively, with some innovations and high clinical and documentary significance.

Global Identification of HIF-1α Target Genes in Benzene Poisoning Mouse Bone Marrow Cells

Benzene is a hematopoietic toxicant, and hematopoietic cells in bone marrow (BM) are one of the main targets for its action, especially hematopoietic stem cells (HSCs). Hypoxia-inducible factor-1α (HIF-1α) is associated with the metabolism and physiological functions of HSCs. We previously found that the mechanism of regulation of HIF-1α is involved in benzene-induced hematopoietic toxicity. In this study, chromatin immunoprecipitation sequencing (ChIP-Seq) technologies were used to analyze the genome-wide binding spectrum of HIF-1α in mouse BM cells, and specific HIF-1α target genes and pathways associated with benzene toxicity were screened and validated. By application of the ChIP-Seq technique, we identified target genes HIF-1α directly binds to and regulates. Forty-two differentially down-regulated genes containing the HIF-1α specific binding site hypoxia response element (HRE) were found, of which 25 genes were with biological function. Moreover, the enrichment analysis of signal pathways indicated that these genes were significantly enriched in the Jak-STAT signaling pathway, Natural killer cell mediated cytotoxicity, the Fc epsilon RI signaling pathway, Pyrimidine metabolism, the T cell receptor signaling pathway, and Transcriptional misregulation in cancer. After verification, 11 genes involved in HSC self-renewal, cell cycle, differentiation, and apoptosis pathways were found to be significantly reduced, and may participate in benzene-induced hematotoxicity. Our study provides a new academic clue for the mechanism of benzene hematotoxicity.

Electrocardiography-gated dual-source computed tomography in the detection of atrial septal aneurysm

The aim of the current study was to investigate the atrial septal aneurysm (ASA) incidence rate and describe its morphologic features by dual-source computed tomography (DSCT). A total of 8,626 patients (4,284 men and 4,342 women) who underwent DSCT examinations were enrolled. The presence of ASA was defined as the protrusion of the complete or partial interatrial septum with a maximum vertical distance (MVD) from the atrial septum plane of >10 mm during a cardiac cycle and a diameter of the aneurysm base of >15 mm. The MVD and direction of the protrusion, as well as other abnormalities, were recorded. The ASA patients were classified by both gender and directions of protrusion into four groups, including the right atrium (RA) and left atrium (LA) groups in males and females, respectively. Values across groups were compared using the independent-sample t-test and differences in qualitative variables were assessed with the χ² test. Of the 8,626 patients, 51 (0.6%) were diagnosed with ASA (mean age, 62±10 years), including 23 (0.5%) males and 28 (0.6%) females. There were no significant differences in the age (t=-1.37, P>0.05) and incidence rate (χ²=0.43, P>0.05) between the male and female groups. However, there were significant differences in the mean ages (t=-2.20, P<0.05) and the gender proportions (χ²=7.39, P<0.05) of patients in the RA and LA groups. In the two male groups, no significant differences were observed in the diameters of the ASA bases and MVD in the RA and LA groups. In the female groups, the differences in the MVD of protrusion in RA and LA groups were non-significant, whereas the diameters of the base of ASA demonstrated significant differences (t=2.27, P<0.05). In conclusion, the ASA incidence rate was 0.6%, and electrocardiography-gated DSCT scan served as an alternative diagnostic technique for the detection of ASA. It is essential for radiologists to recognize this clinical entity and to minimize misdiagnoses and missed diagnoses.

Plasma metabonomics investigation reveals involvement of fatty acid oxidation in hematotoxicity in Chinese benzene-exposed workers with low white blood cell count

Benzene is an environmental and occupational contaminant. Health hazards associated with occupational benzene exposure is a major public health problem in China. In this study, we analyzed metabolite profiles among plasma samples collected from benzene-exposed workers with low white blood cell count (BLWs) and healthy controls using high-performance liquid chromatography-time-of-flight mass spectrometry. To screen potential benzene hematotoxicity biomarkers and metabolic pathways, principal component analysis was used to examine metabolite profile changes in plasma samples. The alterations in fatty acid oxidation (FAO) pathway were consistent with our previous findings in a mouse model; hence, two key genes were selected and verified in WBC samples. A total of nine identified metabolites were significantly changed in BLWs, which were involved in glutathione metabolism, porphyrin metabolism, lipid metabolism pathway, and FAO metabolism. Furthermore, compared with healthy controls, the mRNA expressions of carnitine acyltransferase (CRAT) and ACADVL were significantly increased in BLWs. Particularly, WBC counts was negatively correlated with the expression of AVADVL in BLWs. These aberrant metabolites could act as potential biomarkers for benzene hematotoxicity. In addition, fatty acid oxidation pathway may play a critical role in the development of hematotoxicity caused by benzene.

Dataset of emission and excitation spectra, UV-vis absorption spectra, and XPS spectra of graphitic C3N4

In this data article, the normalized emission and excitation spectra, the ultraviolet-visible (UV-vis) absorption spectra, and the X-ray photoelectron spectroscopy (XPS) of bulk-powders and nano-structured graphitic C₃N₄ (g-C₃N₄) were presented, which are helpful to get insight into the crystal and electronic structures of g-C₃N₄, especially on determining the energy levels and the mechanisms of luminescence originating from electron transitions. This data article is related to our recent publication (He et al., in press) [1]. The absorption, excitation and emission spectra are vital to illustrate the optoelectronic performances in terms of photoluminescence, photocatalysis, electroluminescence, etc., from the viewpoint of electron transitions intrinsically.

The Zn2Cys6-type transcription factor LeuB cross-links regulation of leucine biosynthesis and iron acquisition in Aspergillus fumigatus

Both branched-chain amino acids (BCAA) and iron are essential nutrients for eukaryotic cells. Previously, the Zn₂Cys₆-type transcription factor Leu3/LeuB was shown to play a crucial role in regulation of BCAA biosynthesis and nitrogen metabolism in Saccharomyces cerevisiae and Aspergillus nidulans. In this study, we found that the A. fumigatus homolog LeuB is involved in regulation of not only BCAA biosynthesis and nitrogen metabolism but also iron acquisition including siderophore metabolism. Lack of LeuB caused a growth defect, which was cured by supplementation with leucine or iron. Moreover, simultaneous inactivation of LeuB and HapX, a bZIP transcription factor required for adaptation to iron starvation, significantly aggravated the growth defect caused by inactivation of one of these regulators during iron starvation. In agreement with a direct role in regulation of both BCAA and iron metabolism, LeuB was found to bind to phylogenetically conserved motifs in promoters of genes involved in BCAA biosynthesis, nitrogen metabolism, and iron acquisition in vitro and in vivo, and was required for full activation of their expression. Lack of LeuB also caused activation of protease activity and autophagy via leucine depletion. Moreover, LeuB inactivation resulted in virulence attenuation of A. fumigatus in Galleria mellonella. Taken together, this study identified a previously uncharacterized direct cross-regulation of BCCA biosynthesis, nitrogen metabolism and iron homeostasis as well as proteolysis.

Adaptation to the host niche is an essential attribute of pathogens. Here we found that the Zn₂Cys₆-type transcription factor LeuB cross-regulates branched-chain amino acid biosynthesis, nitrogen metabolism, iron acquisition via siderophores, and proteasome activity in the mold Aspergillus fumigatus. Lack of this regulatory circuit impaired virulence in an insect infection model. Mammals do neither express Zn₂Cys₆-type transcription factors nor have the capacity to produce branched-chain amino acids or siderophores. Consequently, this regulatory circuit is a paradigm for fungal pathogen-specific adaptation to the host niche.