Application of S-transform-based nonlinear processing for accurate LIBS quantitative analysis of iron ore slurry.

Real-time Fe content monitoring in iron ore slurry is crucial for evaluating concentrate quality and enhancing mineral processing efficiency. Laser-induced breakdown spectroscopy (LIBS) is a promising technique for the online monitoring of elemental content at industrial sites. However, LIBS measurements are hampered by the matrix effect and the self-absorption effect, limiting the precision of linear analytical processes. To overcome this, we propose to introduce a nonlinear processing unit based on the S-transform to incorporate nonlinearity into the data analysis process. This approach integrates a feature selection unit based on the spectral distance variable selection method (SDVS), a nonlinear processing unit based on the S-transform (ST), and a partial least squares regression model (PLS). To demonstrate the improvement in accuracy achieved through nonlinear processing, a comparative analysis involving five models, Raw-PLS, SDVS-PLS, ST-PLS, SDVS-ANN, and SDVS-ST-PLS, is conducted. The results reveal a significant improvement in the performance of the SDVS-ST-PLS model, effectively facilitating the successful application of the LIBSlurry analyzer to the mineral flotation process.

Efficient weakly supervised LIBS feature selection method in quantitative analysis of iron ore slurry.

On-stream analysis of the element content in ore slurry plays an important role in the control of the mineral flotation process. Therefore, our laboratory developed a LIBS-based slurry analyzer named LIBSlurry, which can monitor the iron content in slurries in real time. However, achieving high-precision quantitative analysis results of the slurries is challenging. In this paper, a weakly supervised feature selection method named spectral distance variable selection was proposed for the raw spectral data. This method utilizes the prior information that multiple spectra of the same slurry sample have the same reference concentration to assess the important weight of spectral features, and features selected by this prior can avoid over-fitting compared with a traditional wrapper method. The spectral data were collected on-stream of iron ore concentrate slurry samples during the mineral flotation process. The results show that the prediction accuracy is greatly improved compared with the full-spectrum input and other feature selection methods; the root mean square error of the prediction of iron content can be decreased to 0.75%, which helps to realize the successful application of the analyzer.

Phylogenetic and Epidemiological Analysis of Measles Viruses in Shenzhen, China from January 2015 to July 2019.

BACKGROUND Measles morbidity and mortality were significantly reduced after the measles vaccine was introduced in China in 1965. However, measles outbreaks easily occur in densely populated areas, especially where there is no universal vaccination. The outbreak that occurred in Shenzhen, the Chinese city with the largest internal immigration, provides a lesson in measles virus mutation and measles prevention. The present study is a phylogenetic analysis of measles viruses and comparison of clinical signs between individuals with and without vaccination. MATERIAL AND METHODS We performed phylogenetic analysis of the nucleoprotein (N) genes of measles virus from 129 measles patients in Shenzhen from January 2015 to July 2019. Phylogenetic trees were constructed using the neighbor-joining method. RESULTS The phylogenetic analysis showed all viruses were classified into genotype H1. In addition, there is often a seasonal measles outbreak in July each year. The clinical data showed that patients who were unvaccinated were more likely to have coughing, chronic bronchitis, conjunctivitis, catarrh, Koplik spots, and diarrhea. Children of migrant workers and those living in mountainous and rural districts accounted for most measles cases. CONCLUSIONS Our results showed there was a seasonal measles outbreak in Shenzhen Children's Hospital. All the measles virus from 129 measles patients were H1 viruses. The clinical signs also showed a difference between unvaccinated and vaccinated patients. Moreover, most of the unvaccinated patients came from migrant worker families. We suggest there is a need for increased health promotion and vaccination programs for migrant workers and people living in remote villages.

An Image Auxiliary Method for Quantitative Analysis of Laser-Induced Breakdown Spectroscopy.

Improving both the stability and accuracy of laser-induced breakdown spectroscopy (LIBS) is an issue in quantitative analysis. For certain environments outside of the laboratory, consistently and exactly maintaining the distance from the optical system to the sample surface is difficult, and fluctuations of this distance severely affect the stability of the spectrum. In this work, the principal components of the plasma images are extracted and used to correct the spectral line intensities as an auxiliary method to reduce spectral fluctuation. The presented image auxiliary method is combined with univariate analysis and multivariate analysis, and the element concentrations of Cu, Mn, V, and Cr in steel samples are analyzed. For univariate analysis, all the determination coefficients ( R2) of the four elements exceed 0.99, whereas the average relative standard deviations (RSDs) of the intensities decrease from 30.45, 23.14, 27.03, and 22.04%, to 2.13, 3.38, 2.49, and 3.58%, respectively. For the multivariate analysis, the R2 values for Cu, Mn, V, and Cr also all exceed 0.99, and the average RSDs of the predicted concentrations of the validation samples decrease to 2.87, 3.82, 2.86, and 6.51%, respectively.

The Promising Effects of Transplanted Umbilical Cord Mesenchymal Stem Cells on the Treatment in Traumatic Brain Injury.

Many studies have reported the recovery ability of umbilical cord-derived mesenchymal stem cells (UC-MSCs) for neural diseases. In this study, the authors explored the roles of UC-MSCs to treat the traumatic brain injury. Umbilical cord-derived mesenchymal stem cells were isolated from healthy neonatal rat umbilical cord immediately after delivery. The traumatic brain injury (TBI) model was formed by the classical gravity method. The authors detected the behavior changes and measured the levels of inflammatory factors, such as interleukin-lß and tumor necrosis factor-α by enzyme linked immunosorbent assay (ELISA) at 1, 2, 3, 4 weeks after transplantation between TBI treated and untreated with UC-MSCs. Simultaneously, the expression of glial cell line-derived neurotrophic factor (GDNF) and brain derived neurotrophic factor (BDNF) were measured by real-time-polymerase chain reaction and ELISA.The authors found that the group of transplantation UC-MSCs has a significant improvement than other group treated by phosphate buffered saline. In the behavioral test, the Neurological Severity Scores of UC-MSCs + TBI group were lower than TBI group (P < 0.05), but not obviously higher than control group at 2, 3, and 4week, respectively. The inflammatory factors are significantly reduced comparison with TBI group (P < 0.05), but both GDNF and BDNF were higher than TBI group (P < 0.05). The results indicated that UC-MSCs might play an important role in TBI recovery through inhibiting the release of inflammatory factors and increasing the expression of GDNF and BDNF.

Targeted chimera delivery to ovarian cancer cells by heterogeneous gold magnetic nanoparticle.

Efficient delivery of small interfering RNAs (siRNAs) to the targeted cells has remained a significant challenge in clinical applications. In the present study, we developed a novel aptamer-siRNA chimera delivery system mediated by cationic Au-Fe3O4 nanoparticles (NPs). The chimera constructed by VEGF RNA aptamer and Notch3 siRNA was bonded with heterogeneous Au-Fe3O4 nanoparticles by electrostatic interaction. The obtained complex exhibited much higher silencing efficiency against Notch3 gene compared with chimera alone and lipofectamine-siRNA complex, and improved the antitumor effects of the loaded chimera. Moreover, the efficient delivery of the chimera by Au-Fe3O4 NPs could reverse multi-drug resistance (MDR) of ovarian cancer cells against the chemotherapeutic drug cisplatin, indicating its potential capability for future targeted cancer therapy while overcoming MDR.

[In-Situ Analysis of Solid Steel Samples with Remote Double-Pulse Laser-Induced Breakdown Spectroscopy System].

In order to realize real-time, online monitoring of the component of steel and other metal smelting process, we designed a remote double-pulse laser-induced breakdown spectroscopy (LIBS) analysis system which can realize non-contact remote measurement and component analysis for long distance sample. The paper first tests the system on solid standard steel samples, which provides basis for online monitoring the component of molten steel. The experimental results show：laser focal spot is about 1mm in long distance; double-pulse ablation depth is deeper than single pulse's; the optimum delay of double-pulse is non-consistent in different distances; the enhancement effect of double- pulse in 3.1 m is better than that in 2.1 m，and the maximum enhancement is 5.19 of Ti(Ⅰ) 319.99 nm; the calibration curve of R2 is about 0.99, RSD being less than 5%, RMSE being less than 0.021%, LOD being less than 500 ppm for most elements in 2.1 m, which is better than that in 3.1 m.

Osthole Upregulates BDNF to Enhance Adult Hippocampal Neurogenesis in APP/PS1 Transgenic Mice.

Adult hippocampal neurogenesis occurs in the dentate gyrus (DG) of the mouse hippocampus, and plays roles in learning and memory progresses. In amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic mice, a rodent model of Alzheimer's disease (AD), severe impairment of neurogenesis in the dentate subgranular zone (SGZ) of the DG has been reported. Osthole, an active constituent of Cnidium monnieri (L.) CUSSON, has been reported to exert neuroprotective effects and may promote neural stem cell proliferation. However, whether osthole ameliorates spatial memory deficits and improves hippocampal neurogenesis in APP/PS1 mice remains unknown. In this study we found that osthole (30 mg/kg intraperitoneally (i.p.) once daily) treatment dramatically ameliorated the cognitive impairments by Morris Water Maze test and passive avoidance test, and augmented neurogenesis in the DG of hippocampus in APP/PS1 mice. Furthermore, osthole treatment upregulated expression of brain-derived neurotrophic factor (BDNF) and enhanced activation of the BDNF receptor tyrosine receptor kinase B (TrkB) following increased phosphorylation of cyclic AMP response element-binding protein (CREB), indicating that osthole improves neurogenesis via stimulating BDNF/TrkB/CREB signaling in APP/PS1 transgenic mice.

Heart failure, metabolic acidosis, and postoperative multiple organ failure after anesthesia for cesarean section in a patient with Takayasu arteritis: a case report.

The incidence of Takayasu arteritis (TA) is approximately one in 200,000. The prevalence of this disease is higher among Asian women under the age of 30. Most pregnant women with mild TA receive spinal anesthesia for cesarean sections. Despite difficulties in measuring blood pressure, the entire surgical process, including the administering of anesthesia, is generally stable. Studies in this area are rare. The authors report a case of a pregnant woman with TA who received anesthesia for a cesarean section and then suffered for heart failure, metabolic acidosis, and postoperative multiple organ failure. The authors hope to contribute to the clinical studies on the subject of anesthesia for pregnant women with TA.

[Quantitative analysis of alloy steel based on laser induced breakdown spectroscopy with partial least squares method].

In the present paper both the partial least squares (PLS) method and the calibration curve (CC) method are used to quantitatively analyze the laser induced breakdown spectroscopy data obtained from the standard alloy steel samples. Both the major and trace elements were quantitatively analyzed. By comparing the results of two different calibration methods some useful results were obtained: for major elements, the PLS method is better than the CC method in quantitative analysis; more importantly, for the trace elements, the CC method can not give the quantitative results due to the extremely weak characteristic spectral lines, but the PLS method still has a good ability of quantitative analysis. And the regression coefficient of PLS method is compared with the original spectral data with background interference to explain the advantage of the PLS method in the LIBS quantitative analysis. Results proved that the PLS method used in laser induced breakdown spectroscopy is suitable for quantitative analysis of trace elements such as C in the metallurgical industry.

Efficacy and Safety of Tirofiban Before Stenting for Symptomatic Intracranial Atherosclerotic Stenosis: A Randomized Clinical Trial.

BACKGROUND AND OBJECTIVES: Acute stent thrombosis (AST) is not uncommon and even catastrophic during intracranial stenting angioplasty in patients with symptomatic high-grade intracranial atherosclerotic stenosis (ICAS). The purpose of this study was to investigate whether adjuvant intravenous tirofiban before stenting could reduce the risk of AST and periprocedural ischemic stroke in patients receiving stent angioplasty for symptomatic ICAS. METHODS: A prospective, multicenter, open-label, randomized clinical trial was conducted from September 9, 2020, to February 18, 2022, at 10 medical centers in China. Patients intended to receive stent angioplasty for symptomatic high-grade ICAS were enrolled and randomly assigned to receive intravenous tirofiban or not before stenting in a 1:1 ratio. The primary outcomes included the incidence of AST within 30 minutes after stenting, periprocedural new-onset ischemic stroke, and symptomatic intracranial hemorrhage. The outcomes were analyzed using logistic regression analysis to obtain an odds ratio and 95% confidence interval. RESULTS: A total of 200 participants (122 men [61.0%]; median [interquartile ranges] age, 57 [52-66] years) were included in the analysis, with 100 participants randomly assigned to the tirofiban group and 100 participants to the control (no tirofiban) group. The AST incidence was lower in the tirofiban group than that in the control group (4.0% vs 14.0%; adjusted odds ratio, 0.25; 95% CI 0.08-0.82; p = 0.02). No significant difference was observed in the incidence of periprocedural ischemic stroke (7.0% vs 8.0%; p = 0.98) or symptomatic intracranial hemorrhage between the 2 groups. DISCUSSION: This study suggests that adjuvant intravenous tirofiban before stenting could lower the risk of AST during stent angioplasty in patients with symptomatic high-grade ICAS. TRIAL REGISTRATION INFORMATION: URL: chictr.org.cn; Unique identifier: ChiCTR2000031935. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with symptomatic high-grade ICAS, pretreatment with tirofiban decreases the incidence of acute stent thrombosis. This study is Class II due to the unequal distribution of involved arteries between the 2 groups.

Low differentiated microvascular density and low expression of platelet-derived growth factor-BB (PDGF-BB) predict distant metastasis and poor prognosis in clear cell renal cell carcinoma.

OBJECTIVE: To examine the prognostic significance of the expression of platelet-derived growth factor-BB (PDGF-BB) and differentiated microvascular density (MVD) in patients with clear cell renal cell carcinoma (ccRCC). PATIENTS AND METHODS: We used the vascular marker cluster of differentiation 34 (CD34) to identify tumour blood vessels. The expression of PDGF-BB and CD34 was detected by immunohistochemistry (IHC) in tissue microarrays (TMAs) from 100 ccRCCs. Prognostic effects of individual parameters were calculated using Cox regression models and Harrell's concordance index (c-index). RESULTS: Higher grade and more advanced stage ccRCCs had significantly less PDGF-BB expression and differentiated MVD (P < 0.05). Higher PDGF-BB expression was an independent prognostic factor for longer survival, and moreover, the final model built by the addition of PDGF-BB expression improved the predictive accuracy for disease-free survival (c-index 0.707) compared with the clinicopathological-based model (c-index 0.695). PDGF-BB expression was positively associated with differentiated MVD assessed by Spearman correlation and factor analysis (r = 0.634, P < 0.001). CONCLUSION: PDGF-BB is as a novel and promising prognostic marker and antiangiogenic therapeutic target for the treatment of ccRCC.

[Detection and clinical significance of platelet derived growth factor-BB and microvessel density in clear cell renal cell carcinoma].

OBJECTIVE: To investigate the expression of platelet derived growth factor-BB (PDGF-BB) and microvessel density (MVD) marked with CD34 in clear cell renal cell carcinoma (CCRCC) and explore their relevance to clinicopathologic features and prognoses of patients. METHODS: Expressions of PDGF-BB and CD34 in the tissue samples of 100 clear cell renal cell carcinomas were detected by immunohistochemical (IHC) SP staining. The microvessel density (MVD) was counted using Weidner's method. For PDGF-BB assessment, the staining intensity and the proportion of positive tumor cells were analyzed. Staining was considered immunoreactive when brown granules were identified in the cytoplasm or nuclei of tumor cells. Staining intensity and the proportion of positively stained tumor cells in lesions was scored for further analysis. Statistical analysis was performed using the software SPSS 18.0. RESULTS: The MVD value marked by CD34 in the 100 cancer tissues was (105.49 ± 37.95) profiles/HPF. The median value of MVD in the entire cohort was used as the cut-off point for low MVD group (42 cases) and high MVD group (58 cases). The MVD of the low and high MVD groups was (75.12 ± 22.41) profiles/ HPF and (135.86 ± 22.91) profiles/HPF, respectively, with a statistically significant difference (P < 0.001). MVD was significantly correlated with the tumor T staging, histopathological grading and postoperative metastasis in CCRCC (P < 0.05, respectively). Among the 100 CCRCC cases, there were 38 cases with low PDGF-BB expression and 62 cases with high PDGF-BB expression, and the expression of PDGF-BB was significantly correlated with tumor diameter, T staging, histopathological grading and postoperative metastasis in the CCRCC (P < 0.05, respectively). Kaplan-Meier survival analysis showed that the cancer specific survival (CSS) in CCRCC patients with high expression of MVD and PDGF-BB was significantly better than that in the group with low MVD and low PDGF-BB expression (P < 0.001, respectively). Expression of PDGF-BB protein was positively associated with the MVD assessed by Spearman's correlation and factor analysis (r = 0.461, P < 0.001). CONCLUSION: Significantly increased MVD and PDGF-BB expression detected in CCRCC patients indicate a better tumor grading and staging, and a longer survival time.

[Characteristics of lung function in preterm infants with varying degrees of bronchopulmonary dysplasia].

OBJECTIVE: To explore the characteristics of lung function in preterm infants with varying degrees of bronchopulmonary dysplasia(BPD). METHODS: There were 407 infants (278 males and 129 females) were recruited from Shenzhen Children' Hospital between January 2011 and October 2012.Among them 188 term infants (term group)and 113 preterm infants (non-BPD preterm group) were selected as controls. A total of 106 BPD infants from the observation group were divided into mild(n = 48), moderate (n = 42) and severe(n = 16) sub-groups according to the definition of BPD. Infants with diseases interfering with lung function, such as congenital heart disease, congenital diaphragmatic hernia, or thoracic wall deformities, were excluded. Lung function was tested at a postmenstrual age (PMA) of 44 weeks.q test, Dunnett C test and Spearman analysis were used for statistical analysis. RESULTS: The age range was 17-116 d, test weight range 1.83-7.00 kg and test height range 40.0-64.0 cm.In non-BPD preterm group, the respiratory rate (RR) was higher than that in term group ((50 ± 13) vs (44 ± 10) times/min,P < 0.01) ,while the tidal volume(TV), ratio of time to peak tidal expiratory time and expiratory time (Tpef/Te) and peak expiratory flow(TPEF) were all less than those in term group ((25 ± 9) vs (29 ± 7)ml,29% ± 9% vs 33% ± 8%, (59 ± 23) vs (65 ± 25)ml/s,all P < 0.05) .Neither functional residual capacity(FRC) nor lung clearance index (LCI) had significant statistical difference between two groups ((20 ± 5) vs (19 ± 5)ml/kg, 8.4 ± 2.8 vs 8.7 ± 3.4, all P > 0.05)) . In moderate and severe BPD groups, RR ((57 ± 9), (58 ± 10) times/min) were both higher than that in non-BPD group(both P < 0.05) while RR in mild group ((53 ± 13)times/min)had no statistical significant difference with non-BPD group (P > 0.05). The values of TV and LCI in mild, moderate and severe BPD groups have no statistical significance with non-BPD group (all P > 0.05). Except for mild BPD group(24% ± 13%, (18 ± 5)ml/kg), Tpef/Te and FRC in both moderate and severe groups (20% ± 9% and 18% ± 5%, (15 ± 3)and (15 ± 4)ml/kg)were less than those in non-BPD group(all P < 0.05). Only in severe BPD group ((85 ± 11)ml/s), TPEF was higher than that in non-BPD group(P < 0.05). Correlation analysis showed that, except for LCI, all of these parameters were significantly associated with the degree of BPD(all P < 0.05). CONCLUSIONS: For BPD and non-BPD preterm infants, there are various changes in respiratory rhythm, lung volume, ventilation inhomogeneity, ventilatory efficiency and small airway resistance. The increases of pulmonary elastic recoil and degree of major airway constriction are obvious in moderate and severe BPD infants.

[Dynamic changes of lung function in infant of different gestational ages].

OBJECTIVE: To explore the dynamic changes of lung function in infants born at different gestational ages without respiratory complications. METHODS: A total of 110 cases of hospitalized neonatal patients were retrospectively recruited and analyzed at Shenzhen Children's Hospital from July 2010 to August 2012. By gestational age they were divided into 3 groups of full term (37-40 weeks, n = 55, 29 males and 26 females) with an average birth weight (3.1 ± 0.3) kg, late preterm group (34- < 37 weeks, n = 30, 18 males and 12 females) with an average birth weight (2.1 ± 0.3) kg and early preterm (<34 weeks, n = 25, 16 males and 9 females )with an average birth weight (1.4 ± 0.3) kg. At Days 1, 14 and 28, lung function parameters of functional residual capacity (FRC) and lung clear index (LCI) were measured by multiple breath washouts with an ultrasonic flow meter and tidal breathing. One-way ANOVA was used for each index. RESULTS: Tidal expiratory flow 75% remaining tidal volume (TEF75), tidal expiratory flow 50% remaining tidal volume (TEF50) and tidal expiratory flow 25% remaining tidal volume (TEF25) gradually increased at Days 1, 14 and 28 in 3 groups. However respiratory rate (RR) gradually decreased. Compared with full term and late preterm, the early preterm infants had lower TEF75, TEF50 and TEF25, lower the ratios of time to peak expiratory flow and expiratory time (TPTEF/TE), lower ratios of volume to peak expiratory flow and expiratory volume (VPEF/VE) ((71 ± 21) and (66 ± 16) vs (55 ± 19)ml/s, (70 ± 20) and (62 ± 17) vs (51 ± 16)ml/s, (54 ± 17) and (51 ± 13) vs (38 ± 10)ml/s, 37% ± 8% and 34% ± 9% vs 29% ± 6%, 38% ± 6% and 33% ± 8% vs 28% ± 7%, F = 5.82, 8.74, 11.30, 7.72, 16.40, all P < 0.01), higher RR and LCI at Day 28((49 ± 6) and (51 ± 8) vs (56 ± 7)/min, 8.6 ± 2.7 and 8.9 ± 2.2 vs 10.8 ± 2.0,F = 10.09, 7.15, both P < 0.05). At a matched post-menstrual age of 40 weeks, compared with full term and late preterm, the early preterm group had lower TEF50, TEF25, TPTEF/TE, VPEF/VE ((65 ± 21) and (62 ± 12) vs (50 ± 17)ml/s,(51 ± 13) and (47 ± 10) vs (39 ± 10)ml/s, 36% ± 8% and 31% ± 7% vs 30% ± 6%, 37% ± 10% and 32% ± 8% vs 29% ± 6%,F = 4.41, 8.23, 9.08, 7.35, all P < 0.05). CONCLUSIONS: Lung function improves with the elongation of days. The parameters of lung function in early infants are worse than those in full and late-preterm counterparts. At a corrected gestational age of 40 weeks, early preterm infants fail to achieve catch-up growth in lung function. Dynamic monitoring of lung function in preterm infants of different gestational ages is of vital importance for gauging respiratory maturity and assessing lung development especially for preterm infants.

Cell-penetrating magnetic nanoparticles for highly efficient delivery and intracellular imaging of siRNA.

RNA interference is one of the most promising technologies for cancer therapeutics, while the development of a safe and effective small interfering RNA (siRNA) delivery system is still challenging. Here, amphipol polymer and protamine peptide were employed to modify magnetic nanoparticles to form cell-penetrating magnetic nanoparticles (CPMNs). The unique CPMN could efficiently deliver the eGFP siRNA intracellularly and silence the eGFP expression in cancer cells, which was verified by fluorescent imaging of cancer cells. Compared with lipofectamine and polyethyleneimine (PEI), CPMNs showed superior silencing efficiency and biocompatibility with minimum siRNA concentration as 5 nm in serum-containing medium. CPMN was proved to be an efficient siRNA delivery system, which will have great potential in applications as a universal transmembrane carrier for intracellular gene delivery and simultaneous MRI imaging.

Adenovirus 7 Induces Interlukin-6 Expression in Human Airway Epithelial Cells via p38/NF-κB Signaling Pathway.

Human Adenovirus (AdV) infection is very common and usually has a significant impact on children. AdV-induced inflammation is believed to be one of the main causes of severe symptoms. However, an inflammatory response profile in the airway in AdV-infected children is still lacking, and the mechanism underlying AdV-induced inflammation in the airway is also poorly understood. In the current study, we determined the expression of a panel of inflammation cytokines in the airway samples from AdV 7 infected children and further investigated the molecular mechanism underlying AdV 7-induced cytokine expression. Our results showed that eight out of 13 tested inflammatory cytokines were significantly increased in nasal washes of AdV 7-infected children comparing to healthy control, with IL-6 showing the highest enhancement. AdV 7 infection of bronchial epithelial cell line and primary airway epithelial cells confirmed that AdV 7 increased IL-6 mRNA and protein expression in an infection dose-dependent manner. Promoter analysis revealed that AdV 7 infection transactivated IL-6 promoter and a NF-κB binding site in IL-6 promoter was involved in the transactivation. Further analysis showed that upon AdV 7 infection, NF-κB p65 was phosphorylated and translocated into nucleus and bound onto IL-6 promoter. Signaling pathway analysis revealed that p38/NF-κB pathway was involved in AdV 7 infection induced IL-6 elevation. Taken together, our study shows that AdV 7 infection triggers the expression of a range of inflammatory cytokines including IL-6 in the airway of infected children, and AdV 7 enhances IL-6 expression by transactivating IL-6 promoter via p38/NF-κB signaling pathway. Findings of our current study have provided more information toward a better understanding of AdV-induced airway inflammation, which might also benefit the development of intervention strategies.

Towards understanding global patterns of antimicrobial use and resistance in neonatal sepsis: insights from the NeoAMR network.

OBJECTIVE: To gain an understanding of the variation in available resources and clinical practices between neonatal units (NNUs) in the low-income and middle-income country (LMIC) setting to inform the design of an observational study on the burden of unit-level antimicrobial resistance (AMR). DESIGN: A web-based survey using a REDCap database was circulated to NNUs participating in the Neonatal AMR research network. The survey included questions about NNU funding structure, size, admission rates, access to supportive therapies, empirical antimicrobial guidelines and period prevalence of neonatal blood culture isolates and their resistance patterns. SETTING: 39 NNUs from 12 countries. PATIENTS: Any neonate admitted to one of the participating NNUs. INTERVENTIONS: This was an observational cohort study. RESULTS: The number of live births per unit ranged from 513 to 27 700 over the 12-month study period, with the number of neonatal cots ranging from 12 to 110. The proportion of preterm admissions <32 weeks ranged from 0% to 19%, and the majority of units (26/39, 66%) use Essential Medicines List 'Access' antimicrobials as their first-line treatment in neonatal sepsis. Cephalosporin resistance rates in Gram-negative isolates ranged from 26% to 84%, and carbapenem resistance rates ranged from 0% to 81%. Glycopeptide resistance rates among Gram-positive isolates ranged from 0% to 45%. CONCLUSION: AMR is already a significant issue in NNUs worldwide. The apparent burden of AMR in a given NNU in the LMIC setting can be influenced by a range of factors which will vary substantially between NNUs. These variations must be considered when designing interventions to improve neonatal mortality globally.

Proton-sponge coated quantum dots for siRNA delivery and intracellular imaging.

We report the rational design of multifunctional nanoparticles for short-interfering RNA (siRNA) delivery and imaging based on the use of semiconductor quantum dots (QDs) and proton-absorbing polymeric coatings (proton sponges). With a balanced composition of tertiary amine and carboxylic acid groups, these nanoparticles are specifically designed to address longstanding barriers in siRNA delivery such as cellular penetration, endosomal release, carrier unpacking, and intracellular transport. The results demonstrate dramatic improvement in gene silencing efficiency by 10-20-fold and simultaneous reduction in cellular toxicity by 5-6-fold, when compared directly with existing transfection agents for MDA-MB-231 cells. The QD-siRNA nanoparticles are also dual-modality optical and electron-microscopy probes, allowing real-time tracking and ultrastructural localization of QDs during delivery and transfection. These new insights and capabilities represent a major step toward nanoparticle engineering for imaging and therapeutic applications.

Emerging application of quantum dots for drug delivery and therapy.

Quantum dots have proven themselves as powerful fluorescent probes, especially for long-term, multiplexed, and quantitative imaging and detection. Newly engineered quantum dots with integrated targeting, imaging and therapeutic functionalities have become excellent material to study drug delivery in cells and small animals. This fluorescent 'prototype' will provide important information in the rational design of biocompatible drug carriers and will serve as a superior alternative to magnetic and radioactive imaging contrast agents in preclinical drug screening, validation and delivery research. This Editorial article is not intended to offer a comprehensive review on drug delivery, but to highlight the breakthroughs in the emerging applications of quantum dots in this field and to provide our perspective on future research.