Influence of moisturizer and relative humidity on human emissions of fluorescent biological aerosol particles

Utilizing the ultraviolet light-induced fluorescence (UV-LIF) measurement technique as embodied in the Waveband Integrated Bioaerosol Sensor (WIBS-4A), we evaluated the fluorescent particle emissions associated with human shedding while walking in a chamber. The mean emission rates of supermicron (1-10 μm) fluorescent particles were in the range 6.8-7.5 million particles per person-h (~0.3 mg per person-h) across three participants, for conditions when the relative humidity was 60%-70% and no moisturizer was applied after showering. The fluorescent particles displayed a lognormal distribution with the geometric mean diameter in the range 2.5-4 μm and exhibited asymmetry factors that increased with particle size. Use of moisturizer was associated with changes in number and mass emission rates, size distribution, and particle shape. Emission rates were lower when the relative humidity was reduced, but these differences were not statistically significant.

Exacerbation of spontaneous autoimmune nephritis following regulatory T cell depletion in B cell lymphoma 2-interacting mediator knock-out mice

Regulatory T cells (Tregs ) have been recognized as central mediators for maintaining peripheral tolerance and limiting autoimmune diseases. The loss of Tregs or their function has been associated with exacerbation of autoimmune disease. However, the temporary loss of Tregs in the chronic spontaneous disease model has not been investigated. In this study, we evaluated the role of Tregs in a novel chronic spontaneous glomerulonephritis model of B cell lymphoma 2-interacting mediator (Bim) knock-out mice by transient depleting Tregs . Bim is a pro-apoptotic member of the B cell lymphoma 2 (Bcl-2) family. Bim knock-out (Bim-/- ) mice fail to delete autoreactive T cells in thymus, leading to chronic spontaneous autoimmune kidney disease. We found that Treg depletion in Bim-/- mice exacerbated the kidney injury with increased proteinuria, impaired kidney function, weight loss and greater histological injury compared with wild-type mice. There was a significant increase in interstitial infiltrate of inflammatory cells, antibody deposition and tubular damage. Furthermore, the serum levels of cytokines interleukin (IL)-2, IL-4, IL-6, IL-10, IL-17α, interferon (IFN)-γ and tumour necrosis factor (TNF)-α were increased significantly after Treg depletion in Bim-/- mice. This study demonstrates that transient depletion of Tregs leads to enhanced self-reactive T effector cell function followed by exacerbation of kidney disease in the chronic spontaneous kidney disease model of Bim-deficient mice.

Generation of Mesenchymal-Like Stem Cells From Urine in Pediatric Patients

OBJECTIVES

Mesenchymal stem cells (MSCs) have been widely used for regenerative medicine. Traditionally, the procedures of MSC isolation are usually invasive and time-consuming. Urine is merely a body waste, and recent studies have suggested that urine represents an alternative source of stem cells. We, therefore, determined whether the possibility of isolating mesenchymal-like stem cells was practical from human urine.

METHODS

A total of 16 urine samples were collected from pediatric patients. Urine-derived cells were isolated, expanded, and identified for specific cell surface markers using flow cytometry. Cell morphology was observed by microscopy. Osteogenic and adipogenic differentiation potential were determinded by culturing cells in specific induction medium, and assessed by alkaline phosphatase and oil red O stainings, respectively.

RESULTS

Clones were established and passaged successfully from primary cultures of urine cells. Cultured urine-derived cells at passage 3 were fusiform and arranged with certain directionality. Urine-derived cells at passage 5 displayed expressions of cell surface markers (CD29, CD105, CD166, CD90, and CD13). There was no expression of the general hematopoietic cell markers (CD45, CD34, and HLA-DR). Under in vitro induction conditions, urine-derived cells at passage 5 were able to differentiate into osteoblasts, but not adipocytes.

CONCLUSIONS

Urine may be a noninvasive source for mesenchymal-like stem cells. These cells could potentially provide a new source of autologous stem cells for regenerative medicine and cell therapy.

Ocular Behcet's disease is associated with aberrant methylation of interferon regulatory factor 8 (IRF8) in monocyte-derived dendritic cells

Aberrant methylation of interferon regulatory factor 8 (IRF8) has been noted in various tumors. IRF8 has also been reported to be involved in many autoimmune diseases, including Behcet's disease (BD). However, the methylation status of IRF8 in BD has not been reported. To address this issue, we investigated whether the degree of methylation of IRF8 in dendritic cells (DCs) plays a role in the development of BD. We found a lower mRNA expression and a higher methylation level of IRF8 in active ocular BD patients as compared to normal subjects and inactive patients. Treatment with a demethylation agent, 5-Aza-2'-deoxycytidine (DAC) resulted in an increase of mRNA expression and a reduction of the IRF8 methylation level. It also down-regulated the expression of the co-stimulatory molecules CD86, CD80, CD40, and reduced the production of IL-6, IL-1β, IL-23 and IL-12. An inhibition of Th1/Th17 responses was observed as evidenced by a decreased production of IFN-γ, IL-17, and a reduction of IFN-γ/IL-17- producing CD4⁺ T cells following treatment with DAC. This study shows that active ocular BD patients have an aberrant IRF8 methylation status. These findings suggest that epigenetic control of IRF8 expression may offer a future target in the treatment of ocular BD.

High-resolution extremity cone-beam CT with a CMOS detector: Task-based optimization of scintillator thickness

PURPOSE

CMOS x-ray detectors offer small pixel sizes and low electronic noise that may support the development of novel high-resolution imaging applications of cone-beam CT (CBCT). We investigate the effects of CsI scintillator thickness on the performance of CMOS detectors in high resolution imaging tasks, in particular in quantitative imaging of bone microstructure in extremity CBCT.

METHODS

A scintillator thickness-dependent cascaded systems model of CMOS x-ray detectors was developed. Detectability in low-, high- and ultra-high resolution imaging tasks (Gaussian with FWHM of ~250 μm, ~80 μm and ~40 μm, respectively) was studied as a function of scintillator thickness using the theoretical model. Experimental studies were performed on a CBCT test bench equipped with DALSA Xineos3030 CMOS detectors (99 μm pixels) with CsI scintillator thicknesses of 400 μm and 700 μm, and a 0.3 FS compact rotating anode x-ray source. The evaluation involved a radiographic resolution gauge (0.6-5.0 lp/mm), a 127 μm tungsten wire for assessment of 3D resolution, a contrast phantom with tissue-mimicking inserts, and an excised fragment of human tibia for visual assessment of fine trabecular detail.

RESULTS

Experimental studies show ~35% improvement in the frequency of 50% MTF modulation when using the 400 μm scintillator compared to the standard nominal CsI thickness of 700 μm. Even though the high-frequency DQE of the two detectors is comparable, theoretical studies show a 14% to 28% increase in detectability index (d'²) of high- and ultrahigh resolution tasks, respectively, for the detector with 400 μm CsI compared to 700 μm CsI. Experiments confirm the theoretical findings, showing improvements with the adoption of 400 μm panel in the visibility of the radiographic pattern (2× improvement in peak-to-through distance at 4.6 lp/mm) and a 12.5% decrease in the FWHM of the tungsten wire. Reconstructions of the tibial plateau reveal enhanced visibility of trabecular structures with the CMOS detector with 400 μm scinitllator.

CONCLUSION

Applications on CMOS detectors in high resolution CBCT imaging of trabecular bone will benefit from using a thinner scintillator than the current standard in general radiography. The results support the translation of the CMOS sensor with 400 μm CsI onto the clinical prototype of CMOS-based extremity CBCT.

Polymorphisms in Toll-like receptor 3 are associated with asthma-related phenotypes in the Chinese Han patients

Toll-like receptor (TLR) 3 mediates antivirus immunity and is involved in asthma exacerbation and development. However, the genetic association between TLR3 and asthma remains unclear. This study aimed to evaluate the effects of polymorphisms within TLR3 on asthma risk and asthma-related phenotypes in the Chinese Han population. A total number of 462 unrelated adult patients with asthma and 398 healthy volunteers were enrolled in this study. The genotypes of tagging single nucleotide polymorphisms (SNPs) in TLR3 gene were determined using multiplex SNaPshot SNP genotyping assays. Case-control and case-only studies were used to assess any links with asthma and asthma-related phenotypes. The results showed that the genetic variants in TLR3 were associated with asthma-related phenotypes, including eosinophil counts, serum immunoglobulin E levels and lung function. However, there was no obvious association between the TLR3 SNPs and asthma susceptibility or asthma severity. TLR3 polymorphisms may play a considerable role in the pathogenesis of asthma. It will help in better understanding the pathogenesis of asthma and development of more effective strategies for the prevention, prediction and treatment of asthma.

A spray cooling technique for spent fuel assembly stored in pool

For the safety of spent nuclear fuel assemblies stored in storage pool in the extreme condition where the water is lost completely, a passive spray cooling technique was designed, and its effectiveness has been validated by a functional experiment. The spray cooling characteristics of the spent fuel assembly have also been investigated by the experiment.

Image-Based Motion Compensation for High-Resolution Extremities Cone-Beam CT

PURPOSE

Cone-beam CT (CBCT) of the extremities provides high spatial resolution, but its quantitative accuracy may be challenged by involuntary sub-mm patient motion that cannot be eliminated with simple means of external immobilization. We investigate a two-step iterative motion compensation based on a multi-component metric of image sharpness.

METHODS

Motion is considered with respect to locally rigid motion within a particular region of interest, and the method supports application to multiple locally rigid regions. Motion is estimated by maximizing a cost function with three components: a gradient metric encouraging image sharpness, an entropy term that favors high contrast and penalizes streaks, and a penalty term encouraging smooth motion. Motion compensation involved initial coarse estimation of gross motion followed by estimation of fine-scale displacements using high resolution reconstructions. The method was evaluated in simulations with synthetic motion (1-4 mm) applied to a wrist volume obtained on a CMOS-based CBCT testbench. Structural similarity index (SSIM) quantified the agreement between motion-compensated and static data. The algorithm was also tested on a motion contaminated patient scan from dedicated extremities CBCT.

RESULTS

Excellent correction was achieved for the investigated range of displacements, indicated by good visual agreement with the static data. 10-15% improvement in SSIM was attained for 2-4 mm motions. The compensation was robust against increasing motion (4% decrease in SSIM across the investigated range, compared to 14% with no compensation). Consistent performance was achieved across a range of noise levels. Significant mitigation of artifacts was shown in patient data.

CONCLUSION

The results indicate feasibility of image-based motion correction in extremities CBCT without the need for a priori motion models, external trackers, or fiducials.

Shear stress magnitude and transforming growth factor-βeta 1 regulate endothelial to mesenchymal transformation in a three-dimensional culture microfluidic device

A novel microfluidic device with a three-dimensional cell culture chamber was developed to study the role of shear stress magnitude and transforming growth factor-beta 1 (TGF-β1) on endothelial to mesenchymal transformation (EndMT).

SL4, a chalcone-based compound, induces apoptosis in human cancer cells by activation of the ROS/MAPK signalling pathway

OBJECTIVES

SL4, a chalcone-based compound, exhibits clearly inhibitory effects on HIF-1 and has been shown to effectively suppress tumour invasion and angiogenesis in vitro and in vivo. Here, studies were conducted to determine SL4's anti-apoptotic effects and its underlying mechanisms, in human cancer cells.

MATERIALS AND METHODS

Cytotoxicity, apoptotic induction and its involved mechanisms of SL4 were investigated using normal cells, cancer cells and mouse xenograft models. The role of reactive oxygen species (ROS) and mitogen-activated protein kinase (MAPK) signalling in SL4-induced apoptosis was explored by manipulating specific scavenger or signalling inhibitors, in cultured cells.

RESULTS

SL4 significantly inhibited cell population growth of human cancer cell lines but exhibited lower cytotoxicity against normal cells. In addition, SL4 effectively induced apoptosis of Hep3B and MDA-MB-435 cells by activating procaspase-8, -9 and -3, and down-regulating expression levels of XIAP, but did not affect HIF-1 apoptosis-related targets, Survivin and Bcl-XL. Further study showed that SL4 also reduced mitochondrial membrane potential and promoted generation of ROS. ROS generation and apoptotic induction by SL4 were blocked by NAC, a scavenger of ROS, suggesting SL4-induced apoptosis via ROS accumulation. We also found that MAPKs, JNK and p38, but not ERK1/2, to be critical mediators in SL4-induced apoptosis. SP600125 and SB203580, specific inhibitors of JNK kinase and p38 kinase, significantly retarded apoptosis induced by SL4. Moreover, anti-oxidant NAC blocked activation of JNK and p38 induced by SL4, indicating that ROS may act as upstream signalling of JNK and p38 activation. It is noteworthy that animal studies revealed dramatic reduction (49%) in tumour volume after 11 days SL4 treatment.

CONCLUSIONS

These data demonstrate that SL4 induced apoptosis in human cancer cells through activation of the ROS/MAPK signalling pathway, suggesting that it may be a novel lead compound, as a cancer drug candidate, with polypharmacological characteristics.

Association of Genetic Variations in TNFSF15 With Acute Anterior Uveitis in Chinese Han

PURPOSE

T cells play an important role in the pathogenesis of uveitis. Recent studies have indicated that the TNFSF15 gene that encodes the TL1A protein can regulate the differentiation and activation of T cells. TNFSF15 gene polymorphisms have been found to be associated with several autoimmune disorders. A possible association of TNFSF15 with acute anterior uveitis (AAU) has not yet been reported and was therefore the purpose of our study.

METHODS

Eight single nucleotide polymorphisms (SNPs) were examined using TaqMan SNP Genotyping Assay or PCR-restriction fragment length polymorphism in 983 AAU patients and 1128 healthy controls. Genotype distributions and allele frequencies were compared using χ2 analysis between AAU patients and healthy controls. Stratified analysis was also performed according to ankylosing spondylitis (AS) status. The TNFSF15 mRNA expression was quantified by real-time PCR.

RESULTS

A significantly decreased frequency of the TT genotype in TNFSF15-rs3810936 was found in AAU patients (P = 6.36 × 10(-6), corrected P[Pc] = 1.52 × 10(-4), OR = 0.6, 95% CI = 0.5-0.8). Stratification according to AS status did not reveal a difference concerning the association with TNFSF15-rs3810936. None of the other TNFSF15 SNPs tested were associated with AAU.

CONCLUSIONS

This study shows an association between TNFSF15-rs3810936 and AAU and suggests that the TL1A/DR3 pathway may be implicated in the pathogenesis of this disease.

Hemorrhagic cystitis after allogeneic hematopoietic cell transplantation: risk factors, graft source and survival

Although hemorrhagic cystitis (HC) is a common complication of allogeneic hematopoietic cell transplantation (alloHCT), its risk factors and effects on survival are not well known. We evaluated HC in a large cohort (n=1321, 2003-2012) receiving alloHCT from all graft sources, including umbilical cord blood (UCB). We compared HC patients with non-HC (control) patients and examined clinical variables at HC onset and resolution. Of these 1321 patients, 219 (16.6%) developed HC at a median of 22 days after alloHCT. BK viruria was detected in 90% of 109 tested HC patients. Median duration of HC was 27 days. At the time of HC diagnosis, acute GVHD, fever, severe thrombocytopenia and steroid use were more frequent than at the time of HC resolution. In univariate analysis, male sex, age <20 years, myeloablative conditioning with cyclophosphamide and acute GVHD were associated with HC. In multivariate analysis, HC was significantly more common in males and HLA-mismatched UCB graft recipients. Severe grade HC (grade III-IV) was associated with increased treatment-related mortality but not with overall survival at 1 year. HC remains hazardous and therefore better prophylaxis, and early interventions to limit its severity are still needed.

A Multi-Period Optimization Model for Service Providers Using Online Reservation Systems: An Application to Hotels

This paper presents a multi-period optimization model for high margin and zero salvage products in online distribution channels with classifying customers based on number of products required. Taking hotel customers as an example, one is regular customers who reserve rooms for one day, and the other is long term stay (LTS) customers who reserve rooms for a number of days. LTS may guarantee a specific amount of demand and generate opportunity income for a certain number of periods, meanwhile with risk of punishment incurred by overselling. By developing an operational optimization model and exploring the effects of parameters on optimal decisions, we suggest that service providers should make decisions based on the types of customers, number of products required, and duration of multi-period to reduce the loss of reputation and obtain more profit; at the same time, multi-period buying customers should buy products early. Finally, the paper conducts a numerical experiment, and the results are consistent with prevailing situations.