Protective effects of Prussian blue nanozyme against sepsis-induced acute lung injury by activating HO-1.

Sepsis is a life-threatening condition involving dysfunctional organ responses stemming from dysregulated host immune reactions to various infections. The lungs are most prone to failure during sepsis, resulting in acute lung injury (ALI). ALI is associated with oxidative stress and inflammation, and current therapeutic strategies are limited. To develop a more specific treatment, this study aimed to synthesise Prussian blue nanozyme (PBzyme), which can reduce oxidative stress and inflammation, to alleviate ALI. PBzyme with good biosafety was synthesised using a modified hydrothermal method. PBzyme was revealed to be an activator of haem oxygenase-1 (HO-1), improving survival rate and ameliorating lung injury in mice. Zinc protoporphyrin, an inhibitor of HO-1, inhibited the prophylactic therapeutic efficacy of PBzyme on ALI, and affected the nuclear factor-κB signaling pathway and activity of HO-1. This study demonstrates that PBzyme can alleviate oxidative stress and inflammation through HO-1 and has a prophylactic therapeutic effect on ALI. This provides a new strategy and direction for the clinical treatment of sepsis-induced ALI.

FAT1 inhibits AML autophagy and proliferation via downregulating ATG4B expression.

BACKGROUND: Emerging studies have shown that FAT atypical cadherin 1 (FAT1) and autophagy separately inhibits and promotes acute myeloid leukemia (AML) proliferation. However, it is unknown whether FAT1 were associated with autophagy in regulating AML proliferation. METHODS: AML cell lines, 6-week-old male nude mice and AML patient samples were used in this study. qPCR/Western blot and cell viability/3H-TdR incorporation assays were separately used to detect mRNA/protein levels and cell activity/proliferation. Luciferase reporter assay was used to examine gene promoter activity. Co-IP analysis was used to detect the binding of proteins. RESULTS: In this study, we for the first time demonstrated that FAT1 inhibited AML proliferation by decreasing AML autophagy level. Moreover, FAT1 weakened AML autophagy level via decreasing autophagy related 4B (ATG4B) expression. Mechanistically, we found that FAT1 reduced the phosphorylated and intranuclear SMAD family member 2/3 (smad2/3) protein levels, thus decreasing the activity of ATG4B gene promoter. Furthermore, we found that FAT1 competitively bound to TGF-ßR II which decreased the binding of TGF-ßR II to TGF-ßR I and the subsequent phosphorylation of TGF-ßR I, thus reducing the phosphorylation and intranuclear smad2/3. The experiments in nude mice showed that knockdown of FAT1 promoted AML autophagy and proliferation in vivo. CONCLUSIONS: Collectively, these results revealed that FAT1 downregulates ATG4B expression via inhibiting TGFß-smad2/3 signaling activity, thus decreasing the autophagy level and proliferation activity of AML cells. GENERAL SIGNIFICANCE: Our study suggested that the "FAT1-TGFß-smad2/3-ATG4B-autophagy" pathway may be a novel target for developing new targeted drugs to AML treatment.

2,3-Disubstituted Fluorene Scaffold for Efficient Green Phosphorescent Organic Light-Emitting Diodes.

Fluorene is a classic three-membered polycyclic aromatic hydrocarbon, and it has been widely used in optoelectronic devices. Here we explore a simple and efficient strategy for the derivatization at the 2- and 3- positions in fluorene unit. By introducing different types of substituents, we design two pairs of 2,3-disubstituted fluorene isomers and use them as host materials for phosphorescent organic light-emitting diodes (PHOLEDs). The green PHOLEDs hosted by these fluorene derivatives realize high external quantum efficiencies (EQE) over 20 % with low efficiency roll-off. Particularly, the devices hosted by 2TRz3TPA and 2TPA3TRz achieve nearly 24 % EQE and 104 lm W-1 power efficiency. These results clearly demonstrate that the 2,3-disubstituted fluorene platforms are potentially useful for constructing host materials.

Calibration transfer between modelled and commercial pharmaceutical tablet for API quantification using backscattering NIR, Raman and transmission Raman spectroscopy (TRS).

Backscattering NIR, Raman (BSR) and transmission Raman spectroscopy (TRS) coupled with chemometrics have shown to be rapid and non-invasive tools for the quantification of active pharmaceutical ingredient (API) content in tablets. However, the developed models are generally specifically related to the measurement conditions and sample characteristics. In this study, a number of calibration transfer methods, including DS, PDS, DWPDS, GLSW and SST, were evaluated for the spectra correction between modelled tablets produced in the laboratory and commercial samples. Results showed that the NIR and BSR spectra of commercial tablet corrected by DWPDS and PDS, respectively, enabled accurate API predictions with the high ratio of prediction error to deviation (RPDP) values of 2.33 and 3.03. The most successfully approach was achieved with DS corrected TRS data and SiPLS modelling (161 variables) and yielded RMSEP of 0.72 %, R2P of 0.946 and RPDP of 4.35. The proposed calibration transfer strategy offers the opportunities to analyse samples produced in different conditions; in the future, its implication will find extensively process control and quality assurance applications and benefit all possible users in the entire pharmaceutical industry.

Proteomic profiling uncovered the cytosolic superoxide dismutase BsSOD1 associated with plant defence in the herbal orchid Bletilla striata.

The herbal orchid Bletilla striata (Thunb.) Rchb.f. has a long cultivation history and has been widely used in medicines and cosmetics. The fungal infection leaf blight (LB) seriously threatens B. striata cultivation. Here, we systemically collected wild B. striata accessions and isolated the accessions with strong resistance against LB. We carried out proteomic profiling analysis of LB-resistant and LB-susceptible accessions, and identified a large number of differentially expressed proteins with significant gene ontology enrichment for 'oxidoreductase activity.' Of the proteins identified in the reactive oxygen species signalling pathway, the protein abundance of the Cu-Zn superoxide dismutase BsSOD1 and its gene expression level were higher in LB-resistant accessions than in LB-susceptible lines. Transient expression of the dismutase fused with yellow fluorescent protein determined that its subcellular localisation is in the cytoplasm. Our study provides new insights into the molecular markers associated with fungal infection in B. striata.

Effects and mechanism of dexmedetomidine on neuronal cell injury induced by hypoxia-ischemia.

BACKGROUND: The present study aims to investigate the protective effects of dexmedetomidine (DMED) on hypoxia ischemia injury induced by oxygen and glucose deprivation (OGD) in PC12 and primary neuronal cells. METHODS: PC12 cells exposed to OGD was used to establish ischemia model. The OGD-induced cell injury was evaluated by alterations of cell viability, apoptosis and expressions of apoptosis-associated proteins. Oxidative stress and expressions of neurotrophic factors after OGD and DMED treatments were also explored. The activation of possible involved signaling pathways were studied after OGD and DMED treatments, along with the addition of inhibitors of these pathways. Finally, the effects of DMED on primary neuronal cells were verified according to the alterations of inflammatory cytokines release and oxidative stress. RESULTS: DMED obviously increased cell viability and reduced cell apoptosis as well as ratio of Bax/Bcl-2 in OGD-treated PC12 cells. Then, the OGD-induced changes of LDH, MDA, SOD and GSH-Px as well as decreases of neurotrophic factors were all ameliorated by DMED treatment. Key kinases in Notch/NF-κB signaling pathway were up-regulated by OGD, whereas the up-regulations were decreased by DMED. In addition, inhibitor of Notch or NF-κB could augment the effects of DMED on OGD-induced cell injury. Finally, the protective effects of DMED were verified in primary neuronal cells. CONCLUSION: DMED had protective effect on OGD-induced PC12 cell injury, depending on its anti-apoptotic, anti-oxidative activity and the inhibition of Notch/NF-κB activation. Our findings suggested that DMED could be used as a potential therapeutic drug for cerebral ischemia.

Melatonin attenuates postmyocardial infarction injury via increasing Tom70 expression.

Mitochondrial dysfunction leads to reactive oxygen species (ROS) overload, exacerbating injury in myocardial infarction (MI). As a receptor for translocases in the outer mitochondrial membrane (Tom) complex, Tom70 has an unknown function in MI, including melatonin-induced protection against MI injury. We delivered specific small interfering RNAs against Tom70 or lentivirus vectors carrying Tom70a sequences into the left ventricles of mice or to cultured neonatal murine ventricular myocytes (NMVMs). At 48 h post-transfection, the left anterior descending coronary arteries of mice were permanently ligated, while the NMVMs underwent continuous hypoxia. At 24 h after ischemia/hypoxia, oxidative stress was assessed by dihydroethidium and lucigenin-enhanced luminescence, mitochondrial damage by transmission electron microscopy and ATP content, and cell apoptosis by terminal deoxynucleotidyl transferase dUTP nick-end labeling and caspase-3 assay. At 4 weeks after ischemia, cardiac function and fibrosis were evaluated in mice by echocardiography and Masson's trichrome staining, respectively. Ischemic/hypoxic insult reduced Tom70 expression in cardiomyocytes. Tom70 downregulation aggravated post-MI injury, with increased mitochondrial fragmentation and ROS overload. In contrast, Tom70 upregulation alleviated post-MI injury, with improved mitochondrial integrity and decreased ROS production. PGC-1α/Tom70 expression in ischemic myocardium was increased with melatonin alone, but not when combined with luzindole. Melatonin attenuated post-MI injury in control but not in Tom70-deficient mice. N-acetylcysteine (NAC) reversed the adverse effects of Tom70 deficiency in mitochondria and cardiomyocytes, but at a much higher concentration than melatonin. Our findings showed that Tom70 is essential for melatonin-induced protection against post-MI injury, by breaking the cycle of mitochondrial impairment and ROS generation.

Computer-aided design, structural dynamics analysis, and in vitro susceptibility test of antibacterial peptides incorporating unnatural amino acids against microbial infections.

BACKGROUND AND OBJECTIVE: Antibacterial peptides (ABPs) are essential components of host defense against microbial infections present in all domains of life. The AMPs incorporating unnatural amino acids (uABPs) exhibit several advantages over naturally occurring AMPs based on factors such as bioavailability, metabolic stability and overall toxicity. METHODS: Computer-aided modeling and in vitro susceptibility test were combined to rationally design short uABPs with potent antimicrobial activity. In the procedure, peptide characterization and machine learning modeling were used to develop statistical regression predictors, which were then employed to guide the molecular design and structural optimization of uABPs, to which a number of commercially available unnatural amino acids were introduced. RESULTS: An improved uABP population was obtained, from which several promising candidates were successfully prepared and their antibacterial potencies against three bacterial strains Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli were measured using broth microdilution assay. Consequently, four uABPs with hybrid structure property were determined to have high potency against the tested strains with minimum inhibitory concentration (MIC) of <50 µg/ml. CONCLUSIONS: Molecular dynamics (MD) simulations revealed that the designed uABPs are amphipathic helix in solution but they would largely unfold when spontaneously embedding into an artificial lipid bilayer that mimics microbial membrane.

Quantification for total demethylation potential of environmental samples utilizing the EGFP reporter gene.

The demethylation potential of pollutants is arguably an innate component of their toxicity in environmental samples. A method was developed for determining the total demethylation potential of food samples (TDQ). The demethylation epigenetic toxicity was determined using the Hep G2 cell line transfected with pEGFP-C3 plasmids containing a methylated promoter of the EGFP reporter gene. The total demethylation potential of the sample extracts (the 5-AZA-CdR demethylation toxic equivalency) can be quantified within one week by using a standard curve of the 5-AZA-CdR demethylation agent. To explore the applicability of TDQ for environmental samples, 17 groundwater samples were collected from heavy polluted Kuihe river and the total demethylation potentials of the sample extracts were measured successfully. Meaningful demethylation toxic equivalencies ranging from 0.00050 to 0.01747µM were found in all groundwater sample extracts. Among 19 kinds of inorganic substance, As and Cd played important roles for individual contribution to the total demethylation epigenetic toxicity. The TDQ assay is reliable and fast for quantifying the DNA demethylation potential of environmental sample extracts, which may improve epigenetic toxicity evaluations for human risk assessment, and the consistent consuming of groundwater alongside the Kuihe river pose unexpected epigenetic health risk to the local residents.

[Study on brand traceability of vinegar based on near infrared spectroscopy technology].

In the present paper, 152 vinegar samples with four different brands were chosen as research targets, and their near infrared spectra were collected by diffusion reflection mode and transmission mode, respectively. Furthermore, the brand traceability models for edible vinegar were constructed. The effects of the collection mode and pretreatment methods of spectrum on the precision of traceability models were investigated intensively. The models constructed by PLS1-DA modeling method using spectrum data of 114 training samples were applied to predict 38 test samples, and R2, RMSEC and RMSEP of the model based on transmission mode data were 0.92, 0.113 and 0.127, respectively, with recognition rate of 76.32%, and those based on diffusion reflection mode data were 0.97, 0.102 and 0.119, with recognition rate of 86.84%. The results demonstrated that the near infrared spectrum combined with PLS1-DA can be used to establish the brand traceability models for edible vinegar, and diffuse reflection mode is more beneficial for predictive ability of the model.

[Rapid identification of Coix seed varieties by near infrared spectroscopy].

Unsupervised learning algorithm-principal component analysis (PCA), and supervised learning algorithm-learning vector quantization (LVQ) neural network and support vector machine (SVM) were used to carry out qualitative discriminant analysis of different varieties of coix seed from different regions. Since nutrient compositions of different varieties coix seed samples from different origins were complex and the contents were similar, characteristic variables of two kinds of coix seed were alike, the scores plot of their principal components seriously overlapped and the categories of coix seed were difficult to distinguish While satisfactory results were obtained by LVQ neural network and SVM. The accuracy of LVQ neural network prediction is 90. 91%, while the classification accuracy of SVM, whose penalty parameter and kernel function parameter were optimized, can be up to 100%. The results show that NIRS combined with chemometrics can be used as a rapid, nondestructive and reliable method to identify coix seed varieties and provide technical reference for market regulation.

[Chemical constituents from flowers of Gardenia jasminoides].

OBJECTIVE: To study the chemical constituents from flowers of Gardenia jasminoides. METHODS: The compounds were isolated and purified by column chromatography and their structures were elucidated through spectroscopic techniques (NMR) and physicochemical properties. RESULTS: 15 compounds were isolated from flowers of G. jasminoides, and identified as 5, 7, 3'-trihydroxy-6, 4', 5'-trimethoxyflavone (1), 5, 7, 3', 5'- tetrahydroxy-6, 4'-dymethoxyflavone (2), kaempferol (3), quercetin (4), 3beta,23- dihydroxyurs-12-en-28-oic acid (5), 3beta,19alpha-dihydroxy-urs-12-en-28-oic acid (6), 3beta,19alpha,23-trihydroxy-urs-12-en-28-oic acid (7), emodin (8), physcion (9), crocin-I (10), beta-daucosterol (11), beta-sitosterol (12), stearic acid (13), palmitic acid (14), oleic acid (15). CONCLUSION: Compounds 1 - 15 are isolated from flowers of G. jasminoides and compounds 5 and 6 are isolated from genus Gardenia for the first time.

The neurobehavioral impact of manganese: results and challenges obtained by a meta-analysis of individual participant data.

Results from a meta-analysis of aggregated data provoked a new analysis using individual data on the neuropsychological performance of occupationally exposed workers. Data from eight studies examining 579 exposed and 433 reference participants were included, 28 performance variables analyzed. The performance scores were adjusted for well-known individual-level covariates; the influence of possible, but unknown study-level covariates was attenuated by means of a z-normalization. Associations between performance and exposure were estimated by ANOVAs and ANCOVAs, the latter representing multi-level models. Four cognitive and motor performance variables each indicated significantly lower performances of exposed individuals when confounding was considered; slowed motor performances and deficits in attention and short-term memory were found. Performance on a single test was significantly related to the biomarker manganese in blood. The outcomes on susceptibility were weak. The slowing of responses was the most distinct feature of performances of exposed workers. It remains unclear, whether this result is related to the employed tests or provides important information about early stages of the neurotoxic impairment. More specific cognitive tests need to be employed to answer this question. The lack of dose-response relationships was related to features of the biomarker: it does not reflect the Mn in brain responsible for changes in performances.

[Studies on the brand traceability of milk powder based on NIR spectroscopy technology].

Brand traceability of several different kinds of milk powder was studied by combining near infrared spectroscopy diffuse reflectance mode with soft independent modeling of class analogy (SIMCA) in the present paper. The near infrared spectrum of 138 samples, including 54 Guangming milk powder samples, 43 Netherlands samples, and 33 Nestle samples and 8 Yili samples, were collected. After pretreatment of full spectrum data variables in training set, principal component analysis was performed, and the contribution rate of the cumulative variance of the first three principal components was about 99.07%. Milk powder principal component regression model based on SIMCA was established, and used to classify the milk powder samples in prediction sets. The results showed that the recognition rate of Guangming milk powder, Netherlands milk powder and Nestle milk powder was 78%, 75% and 100%, the rejection rate was 100%, 87%, and 88%, respectively. Therefore, the near infrared spectroscopy combined with SIMCA model can classify milk powder with high accuracy, and is a promising identification method of milk powder variety.

[Methods for grain size analysis of nanomedicines].

As nanomedicines are developing fast in both academic and market areas, building up suitable methods for nanomedicine analysis with proper techniques is an important subject, requiring further research. The techniques, which could be employed for grain size analysis of nanomedicines, were reviewed. Several key techniques were discussed with their principles, scope of applications, advantages and defects. Their applications to nanomedine analysis were discussed according to the properties of different nanomedicines, with the purpose of providing some suggestions for the control and administration of nanomedicines.

Development and validation of a stability-indicating gas chromatographic method for quality control of residual solvents in blonanserin: a novel atypical antipsychotic agent.

Blonanserin is a novel atypical antipsychotic agent for the treatment of schizophrenia. Ethyl alcohol, isopropyl alcohol and toluene are utilized in the synthesis route of this bulk drug. A new validated gas chromatographic (GC) method for the simultaneous determination of residual solvents in blonanserin is described in this paper. Blonanserin was dissolved in N, N-dimethylformamide to make a sample solution that was directly injected into a DB-624 column. A postrun oven temperature at 240°C for approximately 2 h after the analysis cycle was performed to wash out blonanserin residue in the GC column. Quantitation was performed by external standard analyses and the validation was carried out according to International Conference on Harmonization validation guidelines Q2A and Q2B. The method was shown to be specific (no interference in the blank solution), linear (correlation coefficients ≥0.99998, n = 10), accurate (average recoveries between 94.1 and 101.7%), precise (intra-day and inter-day precision ≤2.6%), sensitive (limit of detection ≤0.2 ng, and limit of quantitation ≤0.7 ng), robust (small variations of carrier gas flow, initial oven temperature, temperature ramping rate, injector and detector temperatures did not significantly affect the system suitability test parameters and peak areas) and stable (reference standard and sample solutions were stable over 48 h). This extensively validated method is ready to be used for the quality control of blonanserin.

Statistical means to enhance the comparability of data within a pooled analysis of individual data in neurobehavioral toxicology.

Meta-analyses of individual participant data (IPD) provide important contributions to toxicological risk assessments. However, comparability of individual data cannot be taken for granted when information from different studies has to be summarized. By means of statistical standardization approaches the comparability of data might be increased. An analysis of individual data on the neurobehavioral impact of manganese (Mn) exemplifies challenges and effects of a multilevel statistical procedure. Confounding from individual-level and study-level covariates was shown by analyses of variance, but could be reduced by linear regressions and z-normalization using data of the respective control groups. Fixed models that were used to estimate the impact of the neurotoxic exposure, provided evidence that the employed procedures, especially the z-normalization, effectively reduced variance that was unrelated to the neurotoxic exposure. Even after this statistical treatment the fixed effect models revealed differences among studies that did not seem to be exhaustively explicable by concentration differences obvious from the Mn biomarker at hand. IPD studies using confounded endpoints as effects markers can be reasonably summarized when appropriate statistical operations are employed. For the data at hand the proposed normalization allowed new insights into exposure-effect relationships, in general it appears appropriate to investigate the effect of the independent variable more closely.

Bioaccumulation, maternal transfer and elimination of polybrominated diphenyl ethers in wild frogs.

To investigate bioaccumulation, maternal transfer and elimination of polybrominated diphenyl ethers (PBDEs) in amphibians, we collected adult frogs (Rana limnocharis) from a rice field in an e-waste recycling site in China. We found that ∑PBDEs in the whole frogs and various tissues (brain, liver, testis and egg) ranged from 17.10 to 141.11 ng g(-1) wet weight. Various tissues exhibited a similar PBDE congener profile, which was characterized by intermediate brominated congeners (BDE-99 and BDE-153) as the largest contributors, with less lower brominated congeners (BDE-28 and BDE-47) and higher brominated congeners (BDE-209). The maternal transfer capacity of PBDEs declined with the increase in bromine numbers of PBDE congeners. We suggest that the bromine atom number (the molecular size, to some degree) might be a determining factor for the maternal transport of a PBDE congener rather than K(ow) (Octanol-Water partition coefficient), which expresses a compound's lipophilicity. ∑PBDEs concentrations in frogs decreased over time during a depuration period of 54 days when these wild frogs were brought to the lab from the e-waste recycling site. The half-life of ∑PBDEs was 35 days, with about 14 days for BDE-47, and 36 and 81 days for BDE-99 and BDE-153, respectively. The data shows that the elimination of PBDEs has no essential difference from aquatic and terrestrial species.

Imbalance of matrix metalloproteinases/tissue inhibitor of metalloproteinase-1 and loss of fibronectin expression in patients with congestive heart failure.

OBJECTIVE: Previous studies have demonstrated that an imbalance of matrix metalloproteinases (MMPs)/tissue inhibitors of metalloproteinase-1 (TIMP-1) and a loss of fibronectin are associated with postmyocardial infarction remodeling in rats. The present study was designed to examine this issue in patients with congestive heart failure (CHF). METHODS: We measured plasma levels and the cardiac protein expression of MMPs/TIMP-1 and fibronectin in 39 patients with CHF and 38 controls. RESULTS: Plasma levels of MMP-2, MMP-3, and MMP-9 tended to be higher in patients with CHF (NYHA II: 276 +/- 18, 613 +/- 118, and 245 +/- 43 microg/l, respectively; NYHA III: 302 +/- 20, 850 +/- 132, and 310 +/- 39 microg/l, respectively; NYHA IV: 367 +/- 15, 998 +/- 99, and 392 +/- 27 microg/l, respectively) than in controls (213 +/- 23, 485 +/- 102, and 158 +/- 31 microg/l, respectively), while the plasma TIMP-1 level tended to be lower in patients with CHF (NYHA II: 126 +/- 12 microg/l, NYHA III: 83 +/- 11 microg/l, and NYHA IV: 61 +/- 12 microg/l) than in controls (208 +/- 15 microg/l). Interestingly, the changes in protein expression of MMPs/TIMP-1 were consistent with their plasma concentration. Furthermore, the fibronectin level in the patients with CHF was significantly lower than in the controls. CONCLUSIONS: These data suggest that human CHF is associated with an imbalance of MMPs/TIMP-1 and a concurrent loss of fibronectin.