Synthesis and photocatalysis performances of bismuth oxynitrate photocatalysts with layered structures

A new type of layered oxy-acid salt of bismuth oxynitrate was synthesized by a simple hydrothermal method. The obtained bismuth oxy-nitrates consist of a Bi2O2(2+) layered module inserted into the interlamellar anion modules of NO3(-) and OH(-). Varying amounts of NO3(-) and OH(-) complexes on the surface of the bismuth oxynitrate were also obtained by adjusting the precursor pH before hydrothermal treatment. It was found that the sample prepared with the precursor pH = 5.00 presented the highest photocatalytic activity, with a rate constant of 0.05 min(-1), which is 2 and 6.7 times higher than those presented by the samples with the precursor pH = 7.00 and 1.22, respectively. The largest cathodic to anodic photocurrent switching was also presented by the sample with the precursor pH = 5.00, which can be reasonably attributed to NO3(-) complexes on the surface of the bismuth oxynitrate. The NO3(-) complexes could efficiently migrate the photo-induced holes to the surface of the semiconductor.

β-Cell-targeted blockage of PD1 and CTLA4 pathways prevents development of autoimmune diabetes and acute allogeneic islets rejection

Protection of β cells from autoimmune destruction potentially cures type 1 diabetes mellitus (T1D). During antigen presentation, interactions between cytotoxic T-lymphocyte antigen-4 (CTLA4) and B7 molecules, or programmed death 1 (PD1) and its ligand PDL1, negatively regulate immune responses in a non-redundant manner. Here we employed β-cell-targeted adeno-associated virus serotype 8 (AAV8)-based vectors to overexpress an artificial PDL1-CTLA4Ig polyprotein or interleukin 10 (IL10). β-Cell-targeted expression of PDL1-CTLA4Ig or IL10 preserved β-cell mass and protected NOD mice from T1D development. When NOD mice were treated with vectors at early onset of hyperglycemia, PDL1-CTLA4Ig or IL10 alone failed to normalize the early onset of hyperglycemia. When drug-induced diabetic mice received major histocompatibility complex (MHC)-matched allo-islets, with or without pretreatment of the PDL1-CTLA4Ig-expressing vector, PDL1-CTLA4Ig-expressing islets were protected from rejection for at least 120 days. Similarly, transplantation of PDL1-CTLA4Ig-expressing MHC-matched islets into mice with established T1D resulted in protection of allo-islets from acute rejection, although islet grafts were eventually rejected. Thus the present study demonstrates the potent immuno-suppressive effects of β-cell-targeted PDL1-CTLA4Ig overexpression against T1D development and allo-islet rejection. The gene-based simultaneous inhibition of PD1 and CTLA4 pathways provides a unique strategy for immunosuppression-free tissue/organ transplantation, especially in the setting of no established autoimmunity.

Distribution of pilus islands and alpha-like protein genes of group B Streptococcus colonized in pregnant women in Beijing, China

Group B Streptococcus (GBS) is one of the major pathogens of severe newborn sepsis and meningitis. Understanding its regional molecular epidemiology is helpful for regulating efficient prevention practice. A total of 160 GBS strains were collected from colonized pregnant women in six hospital settings in Beijing, China. Polymerase chain reaction (PCR) assays were used to identify the pilus island (PI), alp genes profiling of the alpha-like protein family, and capsular polysaccharide (cps) serotyping. The clonal relationships between strains were investigated using multilocus sequence typing (MLST). All isolates carried at least one pilus island. The most frequently detected pilus island was PI-2a alone (70 isolates, 43.8 %). The most prevalent alp gene was rib (60 isolates, 37.5 %). Moreover, a strong association was noted between alp genes, serotyping, and pilus island profiles. The GBS isolates under study hinted similar molecular epidemical characteristics in Beijing to those reported worldwide, but having their regional distributional features.

Calibrated breast density methods for full field digital mammography: a system for serial quality control and inter-system generalization

PURPOSE

The authors are developing a system for calibrated breast density measurements using full field digital mammography (FFDM). Breast tissue equivalent (BTE) phantom images are used to establish baseline (BL) calibration curves at time zero. For a given FFDM unit, the full BL dataset is comprised of approximately 160 phantom images, acquired prior to calibrating prospective patient mammograms. BL curves are monitored serially to ensure they produce accurate calibration and require updating when calibration accuracy degrades beyond an acceptable tolerance, rather than acquiring full BL datasets repeatedly. BL updating is a special case of generalizing calibration datasets across FFDM units, referred to as cross-calibration. Serial monitoring, BL updating, and cross-calibration techniques were developed and evaluated.

METHODS

BL curves were established for three Hologic Selenia FFDM units at time zero. In addition, one set of serial phantom images, comprised of equal proportions of adipose and fibroglandular BTE materials (50/50 compositions) of a fixed height, was acquired biweekly and monitored with the cumulative sum (Cusum) technique. These 50/50 composition images were used to update the BL curves when the calibration accuracy degraded beyond a preset tolerance of ±4 standardized units. A second set of serial images, comprised of a wide-range of BTE compositions, was acquired biweekly to evaluate serial monitoring, BL updating, and cross-calibration techniques.

RESULTS

Calibration accuracy can degrade serially and is a function of acquisition technique and phantom height. The authors demonstrated that all heights could be monitored simultaneously while acquiring images of a 50/50 phantom with a fixed height for each acquisition technique biweekly, translating into approximately 16 image acquisitions biweekly per FFDM unit. The same serial images are sufficient for serial monitoring, BL updating, and cross-calibration. Serial calibration accuracy was maintained within ±4 standardized unit variation from the ideal when applying BL updating. BL updating is a special case of cross-calibration; the BL dataset of unit 1 can be converted to the BL dataset for another similar unit (i.e., unit 2) at any given time point using the 16 serial monitoring 50/50 phantom images of unit 2 (or vice versa) acquired near this time point while maintaining the ±4 standardized unit tolerance.

CONCLUSIONS

A methodology for monitoring and maintaining serial calibration accuracy for breast density measurements was evaluated. Calibration datasets for a given unit can be translated forward in time with minimal phantom imaging effort. Similarly, cross-calibration is a method for generalizing calibration datasets across similar units without additional phantom imaging. This methodology will require further evaluation with mammograms for complete validation.

Tailoring pH-responsive acrylic acid microgels with hydrophobic crosslinks for drug release

Amphiphilic microgels that were able to encapsulate and release both hydrophobic and hydrophilic moieties were fabricated via a new methodology using a lab-on-a-chip device.

Solvent sensors based on amorphous ZnSnO thin-film transistors

A feasible mechanism model is proposed to explain the strong sensitivity of a-ZTO TFTs towards solvents.

Stable and efficient transfection of siRNA for mutated KRAS silencing using novel hybrid nanoparticles

siRNA is currently the most widely studied form of RNAi, and it has promising therapeutic potential not just in cancer but also in other diseases such as autoimmune and infectious diseases. However, efficient delivery of siRNA to target cells is being limited by lack of an effective delivery system that ensures efficient transfection into cells while protecting the encapsulated siRNA from nuclease. We hypothesized that a hybrid nanoparticle system composed of human IgG and poloxamer-188, a stealth polymer, will efficiently deliver mutated KRAS siRNA to A549 cells, leading to an efficient knockdown of mutated siRNA while protecting the siRNA from serum nuclease. We also hypothesized that the nanoparticles will not elicit an immunostimulatory effect in murine macrophages and also avoid clearance by macrophages. These nanoparticles were found to efficiently deliver siRNA to the cytoplasm and nuclease of A549 cells in a controlled and sustained manner while avoiding recycling by endosomes. An effective knockdown of mutated KRAS was achieved, which subsequently led to an increased sensitivity to erlotinib. These nanoparticles successfully avoided uptake by murine macrophages and reduced immune responses normally associated with siRNA/nanoparticle therapy. These results demonstrate that the novel hybrid nanoparticles could potentially serve as a platform for efficient delivery of siRNA to cells for stable gene knockdown.

Clinical effectiveness of continuous blood purification in combination with ulinastatin in treating thermoplegia

OBJECTIVE

To explore the clinical effectiveness of continuous blood purification (CBP) in combination with ulinastatin for the treatment of thermoplegia.

PATIENTS AND METHODS

Forty patients (28 men and 12 women) with severe heat stroke were admitted to our hospital's ICU department from June 2010 to August 2013. The patients were randomized into a treatment group (n=21; 15 men and six women, with an average age of 32.9 years) and control group (n=19; 13 men and six women, with an average age of 33.1 years). Patients in the control group underwent treatments of oxygen inhalation, dynamic ECG monitoring, physical cooling methods (ice caps or ice application), whereas patients in the treatment group, in addition to this treatment, were further treated with continuous blood purification in combination with ulinastatin. During administration, the content of one vial was dissolved in 100 mL of physiological saline for intravenous dripping for 1.5 hours.

RESULTS

There were 18 cured cases, one case of sequelae of mild neurological disorders, and two deaths in the treatment group, with the cure rate of 90.48%. In comparison, there were 12 cured cases, three cases of sequelae of mild neurological disorders, and four deaths in the control group, with the cure rate of 78.95%. The overall response rates of rectal temperature drop were determined to be 95.24% and 73.68% for the treatment group and the control group, respectively. Based on the treatment outcomes data, multiple organ dysfunction syndrome (MODS) recovery, deaths and survival outcomes of patients in the treatment group was more favorable than that of the control group. This difference was statistically significant (p < 0.05).

CONCLUSIONS

Continuous blood purification in combination with ulinastatin is effective in treating thermoplegia and warrants further investigation.

Inhibition of human positive cofactor 4 radiosensitizes human esophageal squmaous cell carcinoma cells by suppressing XLF-mediated nonhomologous end joining

Radiotherapy has the widest application to esophageal squamous cell carcinoma (ESCC) patients. Factors associated with DNA damage repair have been shown to function in cell radiosensitivity. Human positive cofactor 4 (PC4) has a role in nonhomologous end joining (NHEJ) and is involved in DNA damage repair. However, the clinical significance and biological role of PC4 in cancer progression and cancer cellular responses to chemoradiotherapy (CRT) remain largely unknown. The aim of the present study was to investigate the potential roles of PC4 in the radiosensitivity of ESCC. In this study, we showed that knockdown of PC4 substantially increased ESCC cell sensitivity to ionizing radiation (IR) both in vitro and in vivo and enhanced radiation-induced apoptosis and mitotic catastrophe (MC). Importantly, we demonstrated that silencing of PC4 suppressed NHEJ by downregulating the expression of XLF in ESCC cells, whereas reconstituting the expression of XLF protein in the PC4-knockdown ESCC cells restored NHEJ activity and radioresistance. Moreover, high expression of PC4 positively correlated with ESCC resistance to CRT and was an independent predictor for short disease-specific survival of ESCC patients in both of our cohorts. These findings suggest that PC4 protects ESCC cells from IR-induced death by enhancing the NHEJ-promoting activity of XLF and could be used as a novel radiosensitivity predictor and a promising therapeutic target for ESCCs.

Personal inhalation exposure to polycyclic aromatic hydrocarbons in urban and rural residents in a typical northern city in China

Personal inhalation exposure samples were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) for 126 selected volunteers during heating and non-heating seasons in a typical northern Chinese city, Taiyuan. Measured personal PAH exposure levels for the urban residents in the heating and non-heating seasons were 690 (540-1051) and 404 (266-544) ng/m(3) , respectively, while, for the rural residents, they were 770 (504-1071) and 312 (201-412) ng/m(3) , respectively. Thus, rural residents are exposed to lower PAH contamination in comparison with the urban residents in the non-heating seasons. In the heating season, personal PAH inhalation exposure levels were comparable between the urban and rural residents, in part owing to the large rate of residential solid fuel consumption in the rural area for household cooking and heating. The estimated incremental lifetime cancer risks (ILCR) due to PAH exposure in Taiyuan were 3.36 × 10(-5) and 2.39 × 10(-5) for the rural and urban residents, respectively, significantly higher than the literature-reported national average level, suggesting an urgent need of PAH pollution control to protect human health.