Role of the cAMP-PKA-NF-κB pathway in Mucin1 over-expression in A549 cells during Respiratory syncytial virus infection.

Respiratory syncytial virus (RSV) is the most common pathogen associated with acute lower respiratory tract infections in infants and young children worldwide. RSV commonly presents as bronchiolitis in young children; however, it can sometimes progress to pneumonia, respiratory failure, apnoea and even death. Although mucin1 (MUC1), a type of transmembrane glycoprotein present on airway epithelial surfaces, plays a crucial anti-inflammatory role in airway infections; however, its roles in RSV-associated acute lower respiratory tract infections have rarely been explored. In this study, we first revealed very high MUC1 protein levels in the exacerbation phase in sputum samples from children with RSV bronchiolitis. Because MUC1 is the downstream target of tumour necrosis factor-alpha (TNF-α) in RSV-infected A549 cells, we observed the inhibition of NF-κB activity, main downstream signalling of TNF-α and remarkably reduced levels of MUC1 in RSV-infected and TNF-α treated A549 cells. Furthermore, the cyclic adenosine monophosphate (cAMP) analogue (dbcAMP) downregulated the protein levels of p-IκBα and MUC1 in TNF-α-treated A549 cells. By contrast, a protein kinase A inhibitor (KT5720) up-regulated the levels of those proteins. dbcAMP and KT5720 had the same effects on MUC1 protein levels in RSV-infected A549 cells. In conclusion, we found that the cAMP-PKA-NF-κB pathway may play a role in the regulation of MUC-1 over-expression during RSV infection.

Association between serum copper level and reproductive health of Women in the United States: a cross-sectional study.

Copper is an indispensable trace element in metabolism. This study aimed to investigate the relationship between copper and reproductive health, and possibly provide new insights for diagnosis and treatment. This study was based on data extracted from the NHANES database (2013-2014 and 2015-2016). The t-test, ANOVA, Chi-square test, multiple linear regression, and restricted cubic spline analysis were used. Serum copper levels were significantly higher in women with gestational diabetes than in those without gestational diabetes (P = 0.0150). Women with higher copper levels and smoking habits tended to deliver overweight babies (P = 0.028). Women with diabetes had higher serum copper and were prone to deliver overweight babies (P = 0.024). Serum copper levels showed a positive relationship with sex hormone-binding globulin (SHBG) levels (P < 0.0001). In this study, serum copper levels were found to be associated with reproductive health in women. Further studies are required to draw causal inferences.

On-board measurements of OC/EC ratio, mixing state, and light absorption of ship-emitted particles.

Carbonaceous aerosols play important roles in environmental impacts and climate effects. The characteristics of ship-emitted carbonaceous aerosols keep unclear under the latest global low sulfur fuel oil policy. This study selected four ocean-going vessels burning low sulfur fuel oils for on-board exhaust testing. The emission factors of ship carbonaceous aerosols were obtained under different engine types (main and auxiliary engines), fuel types, and engine loads. Our results showed that fuel and engine types were both important factors affecting carbonaceous aerosol emissions for ship engines. The emission factors of OC and EC from main engines were 1.18 ± 0.62 and 0.06 ± 0.04 g/kg burning heavy fuel oil (HFO), while 0.52 ± 0.35 and 0.04 ± 0.03 g/kg burning marine gas oil (MGO), respectively. The OC/EC ratios of ship-emitted particles were within a large range of 2 to 23. The OC/EC ratios from the main engines were significantly higher than those from the auxiliary engines by a factor of 6.3. The result of chemical mixing states of ship-emitted particles observed by a single particle mass spectrometer (SPAMS) showed that OC and EC were internally mixed and existed as the ECOC-bonded forms in single particles. The measured light absorption of ship-emitted particles with higher OC/EC ratios showed an evident short-wave absorption enhancement based on the aethalometer AE-33. Our results implied that ship-emitted carbonaceous aerosols (especially with high OC/EC ratios) could not be uniformly treated regarding the optical properties to more precisely estimate their potential environmental impacts and climate effects in model systems in the future.

Impact of Ship Emissions on Air Quality in the Greater Bay Area in China under the Latest Global Marine Fuel Regulation.

As the main anthropogenic source in open seas and coastal areas, ship emissions impact the climate, air quality, and human health. The latest marine fuel regulation with a sulfur content limit of 0.5% went into effect globally on January 1, 2020. Investigations of ship emissions after fuel switching are necessary. In this study, online field measurements at an urban coastal site and modeling simulations were conducted to detect the impact of ship emissions on air quality in the Greater Bay Area (GBA) in China under new fuel regulation. By utilizing a high mass-resolution single particle mass spectrometer, the vanadium(V) signal was critically identified and was taken as a robust indicator for ship-emitted particles (with relative peak area > 0.1). The considerable number fractions of high-V particles (up to 30-40% during ship plumes) indicated that heavy fuel oils via simple desulfurization or blending processes with low-sulfur fuels were extensively used in the GBA to meet the global 0.5% sulfur cap. Our results showed that ship-emitted particulate matter and NOx contributed up to 21.4% and 39.5% to the ambient, respectively, in the summertime, significantly affecting the air quality in the GBA. The sea-land breeze circulation also played an important role in the transport pattern of ship-emitted pollutants in the GBA.

Diverse changes in shipping emissions around the Western Pacific ports under the coeffect of the epidemic and fuel oil policy.

The Western Pacific Ocean (the WPO), as one of the busiest shipping areas in the world, holds a complex water traffic network. In 2020, the International Maritime Organization (IMO) low-sulfur fuel regulations were implemented globally, while the COVID-19 outbreak influenced shipping activities together. This study aimed to assess the combined impact of epidemics and low-sulfur fuel policies on ship emissions, as well as their environmental effects on the WPO. The ship emission model based on the Automatic Identification System (AIS) data was applied to analyze the monthly emission variations during 2018-2020. It was found that the epidemic had obvious diverse influences on the coastal ports in the WPO. Overall, shipping emissions declined by 15 %-30 % in the first half of 2020 compared with those in 2019 due to the COVID-19 lockdown, whereas they rebounded in the second half as a result of trade recovery. The pollutants discharged per unit of cargo by ships rose after the large-range lockdown. China's multiphase domestic emission control areas (DECAs) and the IMO global low-sulfur fuel regulation have greatly reduced SO2 emissions from ships and caused them to "bypass and come back" to save fuel costs around emission control areas from 2018 to 2020. Based on satellite data and land-based measurements, it was found that the air quality over sea water and coastal cities has shown a positive response to changes in ship-emitted NOx and SO2. Our results reveal that changes in shipping emissions during typical periods, depending on their niches in the complex port traffic network, call for further efforts for cleaner fuel oils, optimized ECA and ship lane coordination in the future. Shipping related air pollutions during the later economic recovery also needs to be addressed after international scale standing-by events.

CXCL12/CXCR4 Axis is Involved in the Recruitment of NK Cells by HMGB1 Contributing to Persistent Airway Inflammation and AHR During the Late Stage of RSV Infection.

We previously showed that both high-mobility group box-1 (HMGB1) and natural killer (NK) cells contribute to respiratory syncytial virus (RSV)-induced persistent airway inflammation and airway hyperresponsiveness (AHR). Meanwhile, Chemokine (C-X-C motif) ligand 12 (CXCL12) and its specific receptor (chemokine receptor 4, CXCR4) play important roles in recruitment of immune cells. CXCL12 has been reported to form a complex with HMGB1 that binds to CXCR4 and increases inflammatory cell migration. The relationship between HMGB1, NK cells and chemokines in RSV-infected model remains unclear. An anti-HMGB1 neutralizing antibody and inhibitor of CXCR4 (AMD3100) was administered to observe changes of NK cells and airway disorders in nude mice and BALB/c mice. Results showed that the mRNA expression and protein levels of HMGB1 were elevated in late stage of RSV infection and persistent airway inflammation and AHR were diminished after administration of anti-HMGB1 antibodies, with an associated significant decrease in CXCR4+ NK cells. In addition, CXCL12 and CXCR4 were reduced after HMGB1 blockade. Treatment with AMD3100 significantly suppressed the recruitment of NK cells and alleviated the airway disorders. Thus, CXCL12/CXCR4 axis is involved in the recruitment of NK cells by HMGB1, contributing to persistent airway inflammation and AHR during the late stage of RSV infection.

IL-17A plays a critical role in RSV infection in children and mice.

BACKGROUND: IL-17A is a pleiotropic cytokine and intimately associated with asthma, but its role in respiratory syncytial virus (RSV) infection is conflicting in the literature. METHODS: Children hospitalized in the respiratory department with RSV infection during RSV pandemic season of 2018-2020 were included. Nasopharyngeal aspirates were collected for pathogen and cytokines determination. In the murine model, RSV intranasal administrations were performed in wild-type and IL-17A-/- mice. Leukocytes and cytokines in bronchoalveolar lavage fluid (BALF), lung histopathology, and airway hyperresponsiveness (AHR) were measured. RORγt mRNA and IL-23R mRNA were semi-quantified by qPCR. RESULTS: IL-17A increased significantly in RSV-infected children and was positively associated with pneumonia severity. In the murine model, IL-17A significantly increased in BALF of mice with RSV infection. Airway inflammation, lung tissue damage and AHR were significantly alleviated in wild-type mice following IL-17A neutralization and in the IL-17A-/- mice. IL-17A decreased by removing CD4+ T cells but increased by depleting CD8+ T cells. IL-6, IL-21, RORγt mRNA and IL-23R mRNA dramatically increased in parallel with the rise of IL-17A. CONCLUSIONS: IL-17A contributes to the airway dysfunctions induced by RSV in children and murine. CD3+CD4+T cells are its major cellular sources and the IL-6/IL-21-IL-23R-RORγt signaling pathway might participate in its regulation.

Trophoblastic mitochondrial DNA induces endothelial dysfunction and NLRP3 inflammasome activation: Implications for preeclampsia.

AIMS: Preeclampsia (PE) is characterised by systemic vascular endothelium dysfunction. Circulating trophoblastic secretions contribute to endothelial dysfunction, resulting in PE; however, the underlying mechanisms remain unclear. Herein, we aimed to determine the potential correlation between the release of trophoblastic mitochondrial deoxyribonucleic acid (DNA) (mtDNA) and endothelium damage in PE. MATERIALS AND METHODS: Umbilical cord sera and tissues from patients with PE were investigated for inflammasome activation. Following this, trophoblastic mitochondria were isolated from HTR-8/SVneo trophoblasts under 21 % oxygen (O2) or hypoxic conditions (1 % O2 for 48 h) for subsequent treatments. Primary human umbilical veinendothelial cells (HUVECs) were isolated from the human umbilical cord and then exposed to a vehicle (phosphate-buffered saline [PBS]), mtDNA, hypo-mtDNA, or hypo-mtDNA with INF39 (nucleotide oligomerisation domain-like receptor family pyrin domain containing 3 [NLRP3]-specific inhibitor) for 12 h before flow cytometry and immunoblotting. The effects of trophoblastic mtDNA on the endothelium were further analysed in vivo using enzyme-linked immunosorbent assay (ELISA) and vascular reactivity assay. The effects of mtDNA on vascular phenotypes were also tested on NLRP3 knockout mice. RESULTS: Elevated interleukin (IL)-1ß in PE sera was accompanied by NLRP3 inflammasome activation in cord tissues. In vitro and in vivo experiments revealed that the release of trophoblastic mtDNA could damage the endothelium via NLRP3 activation, resulting in the overexpression of NLRP3, caspase-1 p20, IL-1ß p17, and gasdermin D (GSDMD); reduced endothelial nitric oxide synthase (eNOS) levels; and impaired vascular relaxation. Flow cytometric analysis confirmed that extensive cell death was induced by mtDNA, and simultaneously, a more pronounced pro-apoptotic effect was caused by hypoxia-treated trophoblastic mtDNA. The NLRP3 knockout or pharmacologic NLRP3 inhibition partially reversed tumour necrosis factor-α (TNF-α) and IL-1ß levels and endothelium-dependent vasodilation in mice. CONCLUSION: These findings demonstrate that trophoblastic mtDNA induced NLRP3/caspase-1/IL-1ß signalling activation, eNOS-related endothelial injury, and vasodilation dysfunction in PE.

Dynamic Ni/V Ratio in the Ship-Emitted Particles Driven by Multiphase Fuel Oil Regulations in Coastal China.

This study aims to investigate the effect of the stepwise marine fuel oil regulations on the concentrations of vanadium (V) and nickel (Ni) in ambient air based on a 4-y (2017-2020) online measurement in Shanghai, a coastal city in China. The annual concentration of V was reduced by 58% due to the switch from Domestic Emission Control Area (DECA) 1.0 to DECA 2.0 and further by 74% after the implementation of the International Maritime Organization (IMO) 2020 regulation, while the reduction rate for Ni was only 27% and then 18% respectively. Consistently, a reduction of 84% in V content and a negligible change in Ni content were measured in 180cst ship oil samples from 2010 to 2020. The similar increasing trend of Ni/V ratios (from <0.4 to >2.0) in both ambient measurement and heavy fuel oil samples suggests that the DECA and IMO 2020 regulations effectively reduced the ambient V. However, nickel content is still enriched in the in-use desulfurized residual oils and ship-emitted particles in coastal China. Meanwhile, the previous ratio between V and Ni cannot be used as a tracer for identifying ship-emitted particles due to its large variation in oils. Further updating of the source profile of ship traffic emissions in coastal cities is necessary in the future.

Establishment and Clinical Application of the Concept of Invalid Extraction Rates in Follicular Unit Extraction.

OBJECTIVE: This study aims to establish the concept of invalid extraction rates in follicular unit extraction and evaluate its clinical value. METHODS: The present study involved 30 patients with alopecia. Three young surgeons (nominated A, B, and C) each performed follicular unit extraction on a randomly selected portion of the donor site of each patient for ten minutes. The outcomes were separately recorded and calculated, and converted to an invalid extraction rate for each surgeon using the formula, "invalid extraction rate = 1 - successfully extracted follicular units/actually extracted units × 100%." RESULTS: The follicular unit invalid extraction efficiency of each surgeon gradually declined. The average efficiency level of surgeon B was evaluated as excellent, while the levels of surgeons A and C were evaluated as good. CONCLUSION: With experience, surgeons can speed up the process of follicular unit extraction and gradually increase performance quality through both extraction speed and success rate.

Predicting Relapse in Patients With Triple Negative Breast Cancer (TNBC) Using a Deep-Learning Approach.

The abundance and/or location of tumor infiltrating lymphocytes (TILs), especially CD8+ T cells, in solid tumors can serve as a prognostic indicator in various types of cancer. However, it is often difficult to select an appropriate threshold value in order to stratify patients into well-defined risk groups. It is also important to select appropriate tumor regions to quantify the abundance of TILs. On the other hand, machine-learning approaches can stratify patients in an unbiased and automatic fashion. Based on immunofluorescence (IF) images of CD8+ T lymphocytes and cancer cells, we develop a machine-learning approach which can predict the risk of relapse for patients with Triple Negative Breast Cancer (TNBC). Tumor-section images from 9 patients with poor outcome and 15 patients with good outcome were used as a training set. Tumor-section images of 29 patients in an independent cohort were used to test the predictive power of our algorithm. In the test cohort, 6 (out of 29) patients who belong to the poor-outcome group were all correctly identified by our algorithm; for the 23 (out of 29) patients who belong to the good-outcome group, 17 were correctly predicted with some evidence that improvement is possible if other measures, such as the grade of tumors, are factored in. Our approach does not involve arbitrarily defined metrics and can be applied to other types of cancer in which the abundance/location of CD8+ T lymphocytes/other types of cells is an indicator of prognosis.

Club cell 10-kDa protein (CC10) inhibits cPLA2/COX2 pathway to alleviate RSV-induced airway inflammation and AHR.

Respiratory syncytial virus (RSV) is the most common viral pathogen causing acute lower respiratory tract infections (LRTI) in infants. Airway epithelial cells, including Club cells, are primary targets of RSV infection. The "Club cell 10-kDa protein" (CC10), produced mainly by Club cells, possesses anti-inflammatory and immunoregulatory properties that are relevant in infection, injury, and allergic reactions. However, its role in the RSV infection is not fully understood. In the clinic, we found that levels of CC10 in the nasopharyngeal aspirates (NPA) of infants, hospitalized with RSV bronchiolitis, were significantly lower than those without LRTI, and were also negatively correlated with the severity of the disease. In BALB/c mice, the CC10 levels in the bronchoalveolar lavage fluid (BALF) were also decreased at the 5th day after infection. When recombinant CC10 was administrated in the mice, RSV-induced airway inflammation and airway hyperresponsiveness (AHR) were alleviated. Similarly, inhibition of cytosolic phospholipase A2 (cPLA2) or cyclooxygenase 2 (COX2), which is a downstream signaling molecule for cPLA2, both alleviated RSV-induced airway inflammation and AHR. Administration of CC10 reduced the phosphorylation of cPLA2 and protein levels of COX-2 in mouse lungs, resulting from infection, thus providing a molecular mechanism for previous reports that CC10 plays a protective role, partly through inhibiting the activity of cPLA2. We conclude that CC10 inhibits the cPLA2/COX2 pathway to alleviate RSV-induced lung airway inflammation and AHR.

Pathogenic difference of respiratory syncytial virus infection in cotton rats of different ages.

Human respiratory syncytial virus (RSV) is the most common viral pathogen of lower respiratory tract infection worldwide. The virus selectively infects the respiratory epithelium, and causes diseases of variable severity in infants and the elderly. However, the differences in pathogenesis in the age groups remain poorly studied. Age is a major determinant of RSV disease, and the most severe morbidity and mortality occur in the infants and the elderly, because of the immature immunity in infants and declining immunity in old age. The cotton rat is a good model of RSV infection as it is naturally susceptible to RSV. In this study, we established an infant/adult/elderly RSV infection model in 3-week, 8-week and 30-week-old cotton rats and infected them with equal dose of RSV. This model exhibited airway neutrophils infiltration. In the 3-week-old group, higher viral load was observed in the lungs and noses, may due to low IFN-α/Mx2 levels. In contrast, the 8-week-old group had adequate IFN-α/Mx2 but exhibited the most obvious pulmonary inflammation and peribronchiolitis. Interestingly, the most severe pathology and delayed viral clearance in the lungs were observed in the 30-week-old group, may related to the increase of mucus induced by TNF-α and the lower antiviral effect of IFN-α. These results clearly revealed that an age-dependent severity of RSV disease and antiviral defense in the cotton rats, which may provide an effective model for personalized vaccine research and specific treatment strategies for different RSV age groups.

High-mobility group box-1 protein from CC10+ club cells promotes type 2 response in the later stage of respiratory syncytial virus infection.

The type 2 immune response, induced by infection of respiratory syncytial virus (RSV), has been linked to asthma development, but it remains unclear how the response is initiated. Here, we reported that the high-mobility group box-1 (HMGB1) protein promotes the type 2 response in the later stage of RSV infection. In mice, we found that type 2 cytokines were elevated in the later stages, which were strongly diminished after administration of anti-HMGB1 antibodies. Further investigation revealed that HMGB1 expression was localized to CC10+ club cells in the lung. In the clinic, levels of HMGB1 in nasopharyngeal aspirates in hospitalized infants with RSV bronchiolitis [median (interquartile range) 161.20 ng/ml (68.06-221.30)] were significantly higher than those without lower respiratory tract infections [21.94 ng/ml (12.12-59.82); P < 0.001]. Moreover, higher levels of HMGB1 correlated with clinical severity. These results reveal a link between viral infection and the asthma-like type 2 responses that are associated with long-term consequences.

Characteristics of particulate-bound mercury at typical sites situated on dust transport paths in China.

The concentrations and seasonal variations of PBM (particulate-bound mercury) were observed at four dust source sites (Duolun, Yulin, Hetian, and Tazhong), two megacities (Shanghai and Beijing), and an island site (Huaniao Island) to obtain the spatiotemporal characteristics of PBM in dust transport path from desert area in China to the East China Sea. The highest annual mean concentrations of PBM in TSP (PBMTSP) were observed at megacity sites, reaching 146.7 pg/m3 and 274.7 pg/m3 in Shanghai and Beijing attributed primarily to anthropogenic emissions, while 39.7 pg/m3, 67.3 pg/m3, 61.0 pg/m3, 23.5 pg/m3 and 43.6 pg/m3 over Duolun, Yulin, Hetian, Tazhong, and Huaniao Island, respectively. PBM concentrations were higher in winter and autumn, while lower in spring and summer due to the variation of meteorological conditions (especially temperature and wind speed) together with the emission sources. Enrichment factors (EFs) of PBMTSP and PBM2.5 reached 158 and 1452 in Beijing, showing the serious anthropogenic emissions impacted on PBM pollution in megacities, and the profound high level of EFs of mercury in sand dust source sites (17-64 for TSP and 38-252 for PM2.5), suggesting the obvious mixing effect of dust and anthropogenic aerosols in dust source areas. Human activities played a major role in the increase of PBM concentrations and the enrichment factors during the long-range transport of air mass in China. The significant anthropogenic mercury emissions in the dust source areas and their long-range transport driven by the East Asian Monsoon might impact on the ecological cycle of mercury and should be taken into the mercury inventories. Coal combustion and smelting contributed 52-94% to PBM over all three types of sampling sites, and mining operations were additional sources of PBM in Yulin. In the coastal area, sea salt is an important source of PBM, and shipping could also contribute a certain proportion to PBM pollution which shouldn't be ignored.

Synergistic inhibitory effects of an engineered antibody-like molecule ATF-Fc and trastuzumab on tumor growth and invasion in a human breast cancer xenograft mouse model.

The overexpression of the oncogene human epidermal growth factor receptor 2 (HER-2) has been associated with decreased disease-free survival and is a marker of poor prognosis of invasive breast cancer. Although the high efficacy of trastuzumab, a drug that targets the HER-2 oncogene, has been widely recognized, the efficiency of the treatment remains at ~30%. Therefore, novel effective treatments are required for patients with recurrent metastatic breast cancer. The present study aimed to investigate the effects of an engineered antibody-like molecule administered alone or in combination with trastuzumab on the tumor growth and metastasis of HER-2-positive breast cancer. Another aim was to investigate novel cancer therapies for HER-2-positive breast cancer. The engineered antibody-like molecule consists of the amino-terminal fragment (ATF) of human urokinase-type plasminogen (uPA) and is conjugated with the Fc fragment of human immunoglobulin G1 (ATF-Fc). The anti-cancer effect of ATF-Fc (alone and in combination with trastuzumab) on tumor cells and in a nude mouse tumor model was evaluated by detecting the expression of uPA, urokinase plasminogen activator receptor (uPAR) and HER-2. In vitro experiments demonstrated that specifically blocking the uPA-uPAR and HER-2 signaling pathways may effectively promote the apoptosis of breast cancer cells. Additionally, ATF-Fc-induced cell death in HER-2-positive breast cancer cells was observed in vivo. When ATF-Fc was administered in combination with trastuzumab, cell death was increased and breast cancer metastasis was reduced. The novel engineered antibody-like molecule ATF-Fc was able to inhibit HER-2-positive breast cancer cell growth and metastasis by interfering with uPA and its receptor (uPA-uPAR) system. Additionally, the antibody-like molecule exhibits a synergistic inhibitory effect when administered in combination with trastuzumab.

Phenomenological modeling of durotaxis.

Cells exhibit qualitatively different behaviors on substrates with different rigidities. The fact that cells are more polarized on the stiffer substrate motivates us to construct a two-dimensional cell with the distribution of focal adhesions dependent on substrate rigidities. This distribution affects the forces exerted by the cell and thereby determines its motion. Our model reproduces the experimental observation that the persistence time is higher on the stiffer substrate. This stiffness-dependent persistence will lead to durotaxis, the preference in moving towards stiffer substrates. This propensity is characterized by the durotaxis index first defined in experiments. We derive and validate a two-dimensional corresponding Fokker-Planck equation associated with our model. Our approach highlights the possible role of the focal adhesion arrangement in durotaxis.

[Overexpression of miR-125b promotes apoptosis of macrophages].

Objective To investigate the expressions of miR-125b and target gene Raf1 proto-oncogene serine/threonine protein kinase (RAF1) in peripheral blood mononuclear cells (PBMCs) of pediatric patients with pulmonary tuberculosis (PTB), and observe the regulation of miR-125b on macrophage apoptosis and activity. Methods PBMCs of patients with PTB and healthy children were collected and separated. Real-time fluorescence quantitative PCR was used to detect mRNA expression level of miR-125b and RAF1, and Western blotting was used to detect the protein level of RAF1. THP-1 macrophages were transfected into miR-125b mimic, negative control mimic (NC-mimic), miR-125b inhibitor and negative control inhibitor (NC-inhibitor), which were cultured for 48 hours. Western blotting was performed to observe the expression of RAF1 in THP-1 macrophages, annexin V-FITC/PI double staining combined with flow cytometry was used to test cell apoptosis, and CCK-8 assay was used to detect cell proliferation. Results The expression of miR-125b in PBMCs in pediatric patients with PTB was downregulated, and mRNA and protein levels of RAF1 were upregulated. When miR-125b was over-expressed in THP-1 macrophages, the expression of RAF1 was reduced to promote the apoptosis of macrophages and decrease cell activity; when the expression of miR-125b was inhibited in THP-1 macrophages, the expression of RAF1 was elevatedand the apoptosis of macrophages was inhibited, the cell activity was promoted. Conclusion In PBMCs of children with PTB, miR-125b level is low. Upregulation of miR-125b in THP-1 macrophages, the apoptosis of THP-1 macrophages is promoted and cell activity is inhibited.

Circulating microRNAs as biomarkers for the early diagnosis of childhood tuberculosis infection.

MicroRNAs (miRNAs) are a class of highly conserved, single-stranded RNA molecules (length, 18-25 nt) that regulate the expression of their target mRNAs. Previous studies have demonstrated that miRNAs may be novel biomarkers in the diagnosis of certain diseases. In order to evaluate the diagnostic value of miRNAs in childhood tuberculosis (TB), the circulating miRNA profile was determined using microarray analysis. An miRNA­gene network was constructed to identify closely associated miRNAs and these miRNAs were validated using reverse transcription­quantitative polymerase chain reaction (RT­qPCR). A receiver operational curve (ROC) was used to evaluate the diagnostic sensitivity and specificity of confirmed miRNAs. The microarray data demonstrated that 29 miRNAs were altered with 15 upregulated and 14 downregulated. The network showed indicated 14 miRNAs that are critical in childhood TB. RT-qPCR validated that miR-1, miR-155, miR­31, miR­146a, miR­10a, miR­125b and miR­150 were downregulated in while miR­29 was upregulated in children with TB compared with uninfected children. The ROC curve data indicated the diagnostic value of single miRNA was as follows: miR­150>miR­146a>miR­125b>miR­31>miR­10a>miR­1>miR­155>miR­29. Notably, a combination of these miRNAs exhibited increased diagnostic value compared with any single miRNA. To the best of our knowledge, the present study is the first to identify the expression profile of circulating miRNAs in childhood TB and demonstrated that miRNAs may be a novel, non­invasive and effective biomarker for the early diagnosis of childhood TB.

Geometry-constraint-scan imaging for in-line phase contrast micro-CT.

X-ray phase contrast computed tomography (CT) uses the phase shift that x-rays undergo when passing through matter, rather than their attenuation, as the imaging signal and may provide better image quality in soft-tissue and biomedical materials with low atomic number. Here a geometry-constraint-scan imaging technique for in-line phase contrast micro-CT is reported. It consists of two circular-trajectory scans with x-ray detector at different positions, the phase projection extraction method with the Fresnel free-propagation theory and the filter back-projection reconstruction algorithm. This method removes the contact-detector scan and the pure phase object assumption in classical in-line phase contrast Micro-CT. Consequently it relaxes the experimental conditions and improves the image contrast. This work comprises a numerical study of this technique and its experimental verification using a biomedical composite dataset measured at an x-ray tube source Micro-CT setup. The numerical and experimental results demonstrate the validity of the presented method. It will be of interest for a wide range of in-line phase contrast Micro-CT applications in biology and medicine.