M1-polarized alveolar macrophages are crucial in a mouse model of transfusion-related acute lung injury.

BACKGROUND: The pathogenesis of transfusion-related acute lung injury (TRALI) progress is incompletely understood, and specific therapies for TRALI are lacking. Alveolar macrophages (AMs) are critical for initiation and resolution of lung inflammation. However, the role of AMs in the pathogenesis of TRALI-associated lung failure is poorly understood. STUDY DESIGN AND METHODS: Mouse model for in vivo imaging of interleukin (IL)-6 activation in AMs was established by intratracheal instillation of a lentiviral vector carrying the luciferase reporter gene. The TRALI mouse model was produced by intraperitoneal lipopolysaccharide plus intravenous major histocompatibility complex Class I monoclonal antibody treatment. We focused on the changes in AMs in the lung during TRALI and examined whether targeting AMs is an effective strategy to alleviate this condition. MEASUREMENTS AND MAIN RESULTS: We confirmed that TRALI progress is accompanied by IL-6 activation in AMs. Further study showed that AMs undergo M1 activation during TRALI progress. AM depletion protected mice from TRALI, and transfusion of M1-polarized AMs into 34-1-2 s-treated mice elevated acute lung injury, indicating that the severity of TRALI was able to be ameliorated by targeting AM polarization. Next, we showed that α1 -antitrypsin (AAT) expression improved lung injury by modulating the production of IL-6 in AMs and decreased polarization of AMs toward the M1 phenotype. CONCLUSIONS: M1-polarized AMs are crucial in a mouse model of TRALI, and AAT may serve as a future treatment for TRALI by regulating the polarization of AMs.

Characterization and Hemostatic Potential of Two Kaolins from Southern China.

The physicochemical properties and potential hemostatic application of Wenchang kaolin and Maoming kaolin were inspected and evaluated. Chemical composition analysis, Fourier transform infrared (FTIR) spectroscopy, surface area determination, X-ray diffraction, particle size, scanning electron microscopy (SEM) observations, and zeta potential analysis were performed to quantify the physical and chemical properties of the two kaolins. The results showed that both kaolins have typical FTIR bands of kaolinite with a weight fraction for kaolinite over 90 wt%. Larger conglobate aggregates of Maoming kaolin demonstrated wider particle size distributions with two peaks at 3.17 and 35.57 µm, while the book-like Wenchang kaolin had narrow particle size distribution, with a frequent size of 5.64 µm. Furthermore, thrombelastography, the whole blood clotting tests (WBCT), plasma recalcification time (PRT) measurement, and MTT assay were performed to measure the clotting activities and biocompatibility of the two kaolins. The results showed that both kaolins could promote blood coagulation with good cytocompatibility, while Wenchang kaolin had a better procoagulant activity than Maoming kaolin. These findings demonstrated Wenchang kaolin to be a more suitable local source material for application as a hemostatic agent.

Psychometric Properties of the Modified Social Environment Questionnaire in Chinese Older Adults.

This study evaluated the psychometric properties of a Chinese version of the 24-item Social Environment Questionnaire (SEQ-C). Confirmatory factor analysis was used to examine the factor validity and measurement invariance (Purpose 1) of the SEQ-C in 453 older adults in Hong Kong. Convergent validity (Purpose 2) and test-retest reliability (Purpose 3) were also measured. The results of the confirmatory factor analysis and measurement invariance supported the four-factor structure (representing companionship, encouragement, neighborhood social cohesion, and role models) of the SEQ-C, in a 15-item model that closely fitted the data. The SEQ-C was also found to have acceptable to satisfactory internal consistency, test-retest reliability, composite reliability, and moderate convergent validity in correlating perceived social support. This study showed that the SEQ-C is a suitable means of measuring the social environments of older adults in Hong Kong.

Generation of carbamoyl phosphate synthetase 1 reporter cell lines for the assessment of ammonia metabolism.

Both primary hepatocytes and stem cells-derived hepatocyte-like cells (HLCs) are major sources for bioartificial liver (BAL). Maintenance of hepatocellular functions and induction of functional maturity of HLCs are critical for BAL's support effect. It remains difficult to assess and improve detoxification functions inherent to hepatocytes, including ammonia clearance. Here, we aim to assess ammonia metabolism and identify ammonia detoxification enhancer by developing an imaging strategy. In hepatoma cell line HepG2, and immortalized hepatic cell line LO2, carbamoyl phosphate synthetase 1 (CPS1) gene, the first enzyme of ammonia-eliminating urea cycle, was labelled with fluorescence protein via CRISPR/Cas9 system. With the reporter-based screening approach, cellular detoxification enhancers were selected among a collection of 182 small molecules. In both CPS1 reporter cell lines, the fluorescence intensity is positively correlated with cellular CPS1 mRNA expression, ammonia elimination and secreted urea, and reflected ammonia detoxification in a dose-dependent manner. Surprisingly, high-level CPS1 reporter clones also reserved many other critical hepatocellular functions, for example albumin secretion and cytochrome 450 metabolic functions. Sodium phenylbutyrate and resveratrol were identified to enhance metabolism-related gene expression and liver-enriched transcription factors C/EBPα, HNF4α. In conclusion, the CPS1-reporter system provides an economic and effective platform for assessment of cellular metabolic function and high-throughput identification of chemical compounds that improve detoxification activities in hepatic lineage cells.

Plasmonic Ag Core-Satellite Nanostructures with a Tunable Silica-Spaced Nanogap for Surface-Enhanced Raman Scattering.

Plasmonic Ag core-satellite nanostructures were synthesized by utilizing the ultrathin silica shell as a spacer to generate a tunable nanogap between the Ag core and satellites. To synthesize the nanoparticles, Ag nanoparticles (Ag NPs) with a diameter of ∼60 nm were synthesized as cores, on which Raman dyes were adsorbed and then tunable ultrathin silica shells from 2.0 to 6.5 nm were coated, followed by the deposition of Ag NPs as satellites onto the silica surface. The relationships between the SERS signal and the important parameters, including the satellite diameter and the nanogap distance, were studied by experimental methods and theoretical calculations. The maximum SERS intensity of the core-satellite nanoparticles was over 14.6 times stronger than that of the isolated Raman-encoded Ag/PATP@SiO2 NP. The theoretical calculations indicated that the local maximum calculated enhancement factor (EF) of the hot spots with a 2.0 nm nanogap was 9.5 × 10(5). The well-defined Ag core-satellite nanostructures have a high structural uniformity and an anomalously strong electromagnetic enhancement for highly quantitative SERS, leading to a better understanding of hot spot formation and providing new insights into the optimal design and synthesis of the hot SERS nanostructures in a controlled manner.

Highly selective colorimetric bacteria sensing based on protein-capped nanoparticles.

A rapid and cost-effective colorimetric sensor has been developed for the detection of bacteria (Bacillus subtilis was selected as an example). The sensor was designed to rely on lysozyme-capped AuNPs with the advantages of effective amplification and high specificity. In the sensing system, lysozyme was able to bind strongly to Bacillus subtilis, which effectively induced a color change of the solution from light purple to purplish red. The lowest concentration of Bacillus subtilis detectable by the naked eye was 4.5 × 10(3) colony-forming units (CFU) mL(-1). Similar results were discernable from UV-Vis absorption measurements. A good specificity was observed through a statistical analysis method using the SPSS software (version 17.0). This simple colorimetric sensor may therefore be a rapid and specific method for a bacterial detection assay in complex samples.

Occurrence and spatial distributions of microcystins in Poyang Lake, the largest freshwater lake in China.

Occurrence and spatial distributions of microcystins (MCs; MC-RR, -YR, -LR, -LA, -LF, -LW) in Poyang Lake were studied during the period from July 6 to July 18, 2012, by using ultra-high-performance liquid chromatography-electrospray ionization tandem triple quadrupole/mass spectrometry (UPLC-MS/MS). MC-RR was the most dominant variant (94.70 and 84.73 % for intracellular (cellular MCs) and extracellular (dissolved MCs) MCs, respectively) in Poyang Lake, followed by MC-LR (4.65 and 13.17 %, respectively), MC-YR (0.8 and 2.63 %, respectively), and MC-LA (0.02 and 0.00 %), while MC-LW and MC-LF were not detected. Total MCs concentrations (intracellular +extracellular MCs) ranged between 0.0036 and 7.97 µg/L, with an average of 0.79 µg/L, and only two sampling stations with the total MCs concentrations exceeded the drinking water guideline level of 1 µg/L for MC-LR proposed by World Health Organization. The overall spatial pattern of intracellular and extracellular MCs in Poyang Lake demonstrates decreasing trends from east to west, and the south part higher than the north part. Intracellular MCs content was negatively correlated with total nitrogen (r = -0.34, p < 0.01) and NO3 (r = -0.35, p < 0.01), while no significant correlation was found between intracellular MCs concentration and total phosphorus, NH4, and NO2 (p > 0.05), suggesting that NO3 might be a regulating factor for MCs production in Poyang Lake. In addition, intracellular MCs concentrations were positively correlated with wind speed, Microcystis and Cyanobacteria biomass (r = 0.34-0.51, p < 0.05), indicating that wind speed plays an important role in the spatial distributions of MCs, and NO3, toxic cyanobacteria (mainly Microcystis), and wind speed seem to be the important forcing factors driving MCs spatial distributions in Poyang Lake.

[Effect of Panax notoginseng saponins on liver drug metablic enzyme activity, mRNA and protein expressions in rats].

To study the effect of Panax notoginseng saponins (PNS) on liver drug metabolic enzyme activity, mRNA and protein expressions in rats. Male Wistar rats were randomly divided into nine groups. After administration of the test drugs, their liver microsomes, liver total RNA and total protein were extracted to detect the regulating effect of PNS on liver drug metabolic enzyme activity-related subtype enzymatic activity, mRNA and protein expression by substrate probe, quantitative PCR and Western Blot technology. The result of this experiment was that PNS could significantly induce CYP1A2 and CYP2E1 enzyme activity, mRNA expression, CYP2E1 protein expression level. PNS significantly induced CYP3A mRNA expression, but with no significant effect in CYP3A enzyme activity level. PNS had no significant effect CYP1A1 and CYP2B mRNA expressions and enzyme activity levels. PNS had selective regulations on different P450 subtypes, and the major subtypes were CYP1A2 and CYP2E1. In clinical practice, particularly in the combination with CYP1A2 and CYP2E1 metabolism-related drugs, full consideration shall be given to the possible drug interactions in order to avoid potential toxic and side effects. Meanwhile, whether the induction effect of CYP2E1 gets involved in ginsenoside's effect incavenging free radicals deserves further studies.

Extracellular Matrix-Mimetic Peptide Scaffolds Prolonged the Hypothermic Preservation of Stem Cells for Storage and Transportation.

Encouraging advances in both regenerative medicine and tissue engineering with stem cells require a short-term preservation protocol to provide enough time for quality control or the transportation of cell products from manufacturing facilities to clinical destinations. The hypothermic preservation of stem cells under refrigerated conditions (2-8 °C) in their specific culture medium provides an alternative and low-cost method for cryopreservation or commercial preservation fluid for short-term storage. However, most stem cells are vulnerable to hypothermia, which might result in cell damage from the cooling process and the lack of extracellular matrix (ECM). Herein, we report a peptide scaffold cell-culture-medium additive for mimicking in vivo ECM to enhance the storage efficiency of mesenchymal stem cells (MSCs) under hypothermic preservation. Peptide scaffolds exhibit protective effects against hypothermic injury by maintaining the viability, proliferation, migration, and differentiation capabilities of cells. The mechanistic study showed that the peptide scaffold was conducive to maintain mitochondrial function by retaining mitochondrial respiration, mitochondrial membrane potential (ΔΨm), and mass to alleviate intracellular and mitochondrial reactive oxygen species (ROS) production. Moreover, the peptide scaffold also prolonged the survival and retained the multipotency of hematopoietic stem and progenitor cells (HSPCs) under hypothermic conditions. In conclusion, these results demonstrate a feasible and convenient preservation system for stem cells that has the potential to promote the clinical application of hematopoietic stem cell therapy.

Platelet 3D Preservation Using a Novel Biomimetic Nanofiber Peptide for Reduced Apoptosis and Easy Storage.

Human platelets (PLTs) are vulnerable to unfavorable conditions, and their adequate supply is limited by strict transportation conditions. We report here that PLTs preserved under three-dimensional (3D) conditions using novel biomimetic nanofiber peptides showed reduced apoptosis compared with classical PLTs stored at 22 °C and facilitated the storage and transportation of PLTs. The mechanism of PLT 3D preservation involves the formation of cross-links and a 3D nanofibrous network by a self-assembled peptide scaffold material at physiological conditions after initiation by triggers in plasma. PLTs adhere to the surface of the nanofibrous network to facilitate the 3D distribution of PLTs. The 3D microstructure, rheological properties, and effect on the inflammatory response and hemolysis were evaluated. Compared to traditional PLTs stored at 22 °C, PLTs subjected to 3D preservation showed similar morphology, number, aggregation activity, and reduced apoptosis. The detection of the reactive oxygen species (ROS) levels demonstrated that both reduced intracellular and mitochondrial ROS levels were correlated with reduced apoptosis. This study reveals a new 3D preservation method for PLTs based on the use of novel biomimetic nanofiber peptides that presents an attractive opportunity for various biomedical applications.

Effect of phase-change material blood containers on the quality of red blood cells during transportation in environmentally-challenging conditions.

BACKGROUND: The effect of phase-change material blood containers on the quality of stored red blood cells (RBCs) transported in the Qinghai-Tibet Plateau remains to be studied. STUDY DESIGN AND METHODS: RBCs stored in a phase-change material blood container were transported from Chengdu to Tibet and then back to Chengdu. The detection time points were the 1st day of fresh-collected RBCs (group 1), the 14th day of resting refrigerated storage (group 2), and the 14th day of plateau transportation under refrigerated storage in the container (group 3). RBC counts, hemoglobin (HGB) content, free hemoglobin (FHb) content, blood biochemical indexes, hemorheologic indexes and 2,3-DPG content were detected. RESULTS: Compared with group 2, RBC counts and HGB were decreased, and the mean corpuscular volume (MCV), FHb and K+ content were increased in group 3. The glucose consumption and lactic acid production were significantly increased in groups 2 and 3. Compared with group 2, the 2,3-DPG content and whole blood viscosity were decreased in group 3. After resting refrigerated storage and plateau transportation, the RBC quality still met the national standard (GB18469-2012 whole blood and component blood quality requirements). CONCLUSION: The phase-change material blood container can be maintained at a constant temperature under plateau environmental conditions, ensuring that the quality of the stored RBCs is compliant with GB18469-2012 whole blood and component blood quality requirements.

Nondestructive Measurement of Hemoglobin in Blood Bags Based on Multi-Pathlength VIS-NIR Spectroscopy.

Hemoglobin concentration is an indicator for assessing blood product quality. To measure hemoglobin concentration in blood products without damaging blood bags, we proposed a method based on visible-near infrared transmission spectroscopy. Complex optical properties of blood bag walls result in measurement irregularities. Analyses showed that the slope of the light intensity-pathlength curve was more robust to the influence of the blood bag wall. In this study, the transmission spectra of red blood cell suspensions at multiple optical pathlengths were obtained, and the slopes of logarithmic light intensity-pathlength curves were calculated through curve fitting. A nondestructive measurement of hemoglobin content was achieved by using a regression model correlating slope spectra and hemoglobin concentration. Sixty samples with hemoglobin concentrations ranging from 72 to 161 g/L were prepared. Among them, 40 samples were used as a calibration set, and the remaining 20 samples were used as a prediction set. The determination coefficient of the prediction set was 0.97, with a mean square error of 2.78 g/L. This result demonstrates that a non-destructive measurement of hemoglobin levels in blood bags can be achieved by multiple-pathlength transmission spectroscopy.

Note: Demodulation of spectral signal modulated by optical chopper with unstable modulation frequency.

When an optical chopper is used to modulate the light source, the rotating speed of the wheel may vary with time and subsequently cause jitter of the modulation frequency. The amplitude calculated from the modulated signal would be distorted when the frequency fluctuations occur. To precisely calculate the amplitude of the modulated light flux, we proposed a method to estimate the range of the frequency fluctuation in the measurement of the spectrum and then extract the amplitude based on the sum of power of the signal in the selected frequency range. Experiments were designed to test the feasibility of the proposed method and the results showed lower root means square error than the conventional way.

Magnetic immunoassay for cancer biomarker detection based on surface-enhanced resonance Raman scattering from coupled plasmonic nanostructures.

A surface-enhanced resonance Raman scattering (SERRS) sensor was developed for the ultrasensitive detection of cancer biomarkers. Capture antibody-coated silver shell magnetic nanoparticles (Fe3O4@Ag MNPs) were utilized as the CEA enrichment platform and the SERRS signal amplification substrate. Gold nanorods (AuNRs) were coated with a thin silver shell to be in resonance with the resonant Raman dye diethylthiatricarbocyanine iodide (DTTC) and the excitation wavelength at 785nm. The silver-coated AuNRs (Au@Ag NRs) were then modified with detection antibody as the SERRS tags. Sandwich immune complexes formed in the presence of the target biomarker carcinoembryonic antigen (CEA), and this formation induced the plasmonic coupling between the Au@Ag NRs and Fe3O4@Ag MNPs. The SERRS signal of DTTC molecules located in the coupled plasmonic nanostructures was significantly enhanced. As a result, the proposed SERRS sensor was able to detect CEA with a low limit of detection of 4.75fg/mL and a wide dynamic linear range from 10fg/mL to 100ng/mL. The sensor provides a novel SERRS strategy for trace analyte detection and has a potential for clinical applications.

Mature dendritic cell derived from cryopreserved immature dendritic cell shows impaired homing ability and reduced anti-viral therapeutic effects.

Cryopreservation is critical in reducing redundant operations and also in quality control in dendritic cell (DC) therapy. Full maturation and efficient homing of DCs to T cell-region constitute a crucial aspect of DC immunotherapy; however, the in vivo migration and distribution pattern, as well as the anti-viral effect of DCs that matured from cryopreserved immature DCs (cryoim-mDCs) remain to be revealed. In the present study, we compared cryoim-mDCs with DCs matured from fresh immature DCs (fmDCs) in the aspects of phenotypes, in vivo homing capacities as well as the anti-viral therapeutic effects to further clarify the effect of cryopreservation on DC-based cytotherapy. The results showed that cryopreservation impaired the homing ability of DCs which was associated with the reduced expression of CCR7 and disturbed cytoskeleton arrangement. Moreover, the antigen-specific CD8+ T cell response induced by cryoim-mDCs was much weaker than that induced by fmDCs in both the spleen and liver draining lymph nodes, which provided reduced protection from viral invasions. In conclusion, cryopreservation is a good method to keep the viability of immature DCs, however, the in vivo homing capacity and anti-viral therapeutic effect of DCs matured from frozen immature DCs were hindered to some extent.

Luminescent 2D bismuth-cadmium-organic frameworks with tunable and white light emission by doping different lanthanide ions.

The first luminescent Bi-Cd-organic framework, Bi2Cd(2,6-pdc)4(H2O)2·H2O (2,6-H2pdc = pyridine-2,6-dicarboxylate), has been synthesized by using bismuth (Bi) oxides and cadmium (Cd) salts as metal sources under hydrothermal conditions. Tunable and white light luminescence was obtained through the doping of different Ln(3+) ions into the Bi-Cd-organic framework.

Ferulic acid protects lymphocytes from radiation-predisposed oxidative stress through extracellular regulated kinase.

PURPOSE: The objective of this study was to investigate the radioprotective effect of ferulic acid (FA) on irradiated lymphocytes and discover the possible mechanisms of protection. MATERIALS AND METHODS: Lymphocytes were pretreated for 12 h with FA (0.001-0.1 µM) and then exposed to 3 Gy radiation. Cell apoptosis, intracellular reactive oxygen species (ROS), and signal pathway was analysed. RESULTS: Irradiation increased cell death, DNA fragmentation and intracellular ROS. Pretreatment with FA significantly reversed this tendency and attenuated the irradiation-induced ROS generation. Furthermore, several anti-apoptotic characteristics of FA were determined, including the ability to diminish cytosolic Ca(2+) concentration, inhibit caspase-3 activation and cytochrome c translocation, upregulate B-cell lymphoma 2 (Bcl-2) and downregulate Bcl-2-associated X protein (Bax) in 3 Gy-irradiated lymphocytes. Signal pathway analysis showed FA decreased the activation of extracellular regulated kinase (ERK), which had been activated by radiation. CONCLUSION: The results suggest that FA had a radioprotective effect through the ERK pathway to inhibit apoptosis and oxidation, and it may be an effective candidate for treating radiation diseases associated with oxidative stress.

Proteomic analysis on structural proteins of Severe Acute Respiratory Syndrome coronavirus.

Recently, a new coronavirus was isolated from the lung tissue of autopsy sample and nasal/throat swabs of the patients with Severe Acute Respiratory Syndrome (SARS) and the causative association with SARS was determined. To reveal further the characteristics of the virus and to provide insight about the molecular mechanism of SARS etiology, a proteomic strategy was utilized to identify the structural proteins of SARS coronavirus (SARS-CoV) isolated from Vero E6 cells infected with the BJ-01 strain of the virus. At first, Western blotting with the convalescent sera from SARS patients demonstrated that there were various structural proteins of SARS-CoV in the cultured supernatant of virus infected-Vero E6 cells and that nucleocaspid (N) protein had a prominent immunogenicity to the convalescent sera from the patients with SARS, while the immune response of spike (S) protein probably binding with membrane (M) glycoprotein was much weaker. Then, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to separate the complex protein constituents, and the strategy of continuous slicing from loading well to the bottom of the gels was utilized to search thoroughly the structural proteins of the virus. The proteins in sliced slots were trypsinized in-gel and identified by mass spectrometry. Three structural proteins named S, N and M proteins of SARS-CoV were uncovered with the sequence coverage of 38.9, 93.1 and 28.1% respectively. Glycosylation modification in S protein was also analyzed and four glycosylation sites were discovered by comparing the mass spectra before and after deglycosylation of the peptides with PNGase F digestion. Matrix-assisted laser desorption/ionization-mass spectrometry determination showed that relative molecular weight of intact N protein is 45 929 Da, which is very close to its theoretically calculated molecular weight 45 935 Da based on the amino acid sequence deduced from the genome with the first amino acid methionine at the N-terminus depleted and second, serine, acetylated, indicating that phosphorylation does not happen at all in the predicted phosphorylation sites within infected cells nor in virus particles. Intriguingly, a series of shorter isoforms of N protein was observed by SDS-PAGE and identified by mass spectrometry characterization. For further confirmation of this phenomenon and its related mechanism, recombinant N protein of SARS-CoV was cleaved in vitro by caspase-3 and -6 respectively. The results demonstrated that these shorter isoforms could be the products from cleavage of caspase-3 rather than that of caspase-6. Further, the relationship between the caspase cleavage and the viral infection to the host cell is discussed.