High-Resolution Quantum Dot Light-Emitting Diodes by Electrohydrodynamic Printing.

Quantum dot light-emitting diodes (QLEDs) have attracted increasing attention due to their excellent electroluminescent properties and compatibility with inkjet printing processes, which show great potential in applications of pixelated displays. However, the relatively low resolution of the inkjet printing technology limits its further development. In this paper, high-resolution QLEDs were successfully fabricated by electrohydrodynamic (EHD) printing. A pixelated quantum dot (QD) emission layer was formed by printing an insulating Teflon mesh on a spin-coated QD layer. The patterned QLEDs show a high resolution of 2540 pixels per inch (PPI), with a maximum external quantum efficiency (EQE) of 20.29% and brightness of 35816 cd/m2. To further demonstrate its potential in full-color display, the fabrication process for the QD layer was changed from spin-coating to EHD printing. The as-printed Teflon effectively blocked direct contact between the hole transport layer and the electron transport layer, thus preventing leakage currents. As a result, the device showed a resolution of 1692 PPI with a maximum EQE of 15.40%. To the best of our knowledge, these results represent the highest resolution and efficiency of pixelated QLEDs using inkjet printing or EHD printing, which demonstrates its huge potential in the application of high-resolution full-color displays.

The warming-up effects of quantum-dot light emitting diodes: A reversible stability issue related to shell traps.

The aging phenomenon is commonly observed in quantum-dot light emitting diodes (QLEDs), involving complex chemical or physical processes. Resolving the underlying mechanism of these aging issues is crucial to deliver reliable electroluminescent devices in future display applications. Here, we report a reversible positive aging phenomenon that the device brightness and efficiency significantly improve after device operation, but recover to initial states after long-time storage or mild heat treatment, which can be termed as warming-up effects. Steady and transient equivalent circuit analysis suggest that the radiative recombination current dramatically increases but electron leakage from the quantum dots (QDs) to hole transport layer becomes more accessible during the warming-up process. Further analysis discloses that the notable enhancement of device efficiency can be ascribed to the filling of shell traps in gradient alloyed QDs. This work reveals a distinct positive aging phenomenon featured with reversibility, and further guidelines would be provided to achieve stable QLED devices in real display applications.

Machine Learning Assisted Stability Analysis of Blue Quantum Dot Light-Emitting Diodes.

The operational stability of the blue quantum dot light-emitting diode (QLED) has been one of the most important obstacles to initialize its industrialization. In this work, we demonstrate a machine learning assisted methodology to illustrate the operational stability of blue QLEDs by analyzing the measurements of over 200 samples (824 QLED devices) including current density-voltage-luminance (J-V-L), impedance spectra (IS), and operational lifetime (T95@1000 cd/m2). The methodology is able to predict the operational lifetime of the QLED with a Pearson correlation coefficient of 0.70 with a convolutional neural network (CNN) model. By applying a classification decision tree analysis of 26 extracted features of J-V-L and IS curves, we illustrate the key features in determining the operational stability. Furthermore, we simulated the device operation using an equivalent circuit model to discuss the device degradation related operational mechanisms.

Blue light-emitting diodes based on colloidal quantum dots with reduced surface-bulk coupling.

To industrialize printed full-color displays based on quantum-dot light-emitting diodes, one must explore the degradation mechanism and improve the operational stability of blue electroluminescence. Here, we report that although state-of-the-art blue quantum dots, with monotonically-graded core/shell/shell structures, feature near-unity photoluminescence quantum efficiency and efficient charge injection, the significant surface-bulk coupling at the quantum-dot level, revealed by the abnormal dipolar excited state, magnifies the impact of surface localized charges and limits operational lifetimes. Inspired by this, we propose blue quantum dots with a large core and an intermediate shell featuring nonmonotonically-graded energy levels. This strategy significantly reduces surface-bulk coupling and tunes emission wavelength without compromising charge injection. Using these quantum dots, we fabricate bottom-emitting devices with emission colors varying from near-Rec.2020-standard blue to sky blue. At an initial luminance of 1000 cd m-2, these devices exhibit T95 operational lifetimes ranging from 75 to 227 h, significantly surpassing the existing records.

Biomimetic Red Blood Cell Membrane-Mediated Nanodrugs Loading Ursolic Acid for Targeting NSCLC Therapy.

As one of the most common cancers worldwide, non-small-cell lung cancer (NSCLC) treatment always fails owing to the tumor microenvironment and resistance. UA, a traditional Chinese medicine, was reported to have antitumor potential in tumor models in vitro and in vivo, but showed impressive results in its potential application for poor water solubility. In this study, a novel biomimetic drug-delivery system based on UA-loaded nanoparticles (UaNPs) with a red blood cell membrane (RBCM) coating was developed. The RBCM-coated UANPs (UMNPs) exhibited improved water solubility, high stability, good biosafety, and efficient tumor accumulation. Importantly, the excellent antitumor efficiency of the UMNPs was confirmed both in vitro and in vivo in cancer models. In addition, we further investigated the antitumor mechanism of UMNPs. The results of Western blotting showed that UMNPs exerted an anticancer effect by inducing the apoptosis and autophagy of NSCLC cells, which makes it superior to free UA. In addition, body weight monitoring, hematoxylin and eosin (HE) analysis, and immunohistochemical (IHC) analysis showed no significant difference between UMNPs and the control group, indicating the safety of UMNPs. Altogether, the preparation of biomimetic UMNPs provides a promising strategy to improve outcomes in NSCLC.

Enhanced antitumor effect of icariin nanoparticles coated with iRGD functionalized erythrocyte membrane.

Lung cancer is the most common cause of incidence and mortality among tumor diseases. Icariin (ICA), a potential Chinese medicine monomer, has been reported to show outstanding antitumor effects. However, the hydrophobic nature and less tumor penetration limit its potential as a topical healing agent. There are few studies report the efficacy of ICA on lung cancer, moreover, there is no biomimetic targeted delivery system in the application of ICA. Herein, we firstly develop a novel ICA bionic targeted nano-preparation, camouflaged by the tumor penetrating peptide iRGD (cRGDKGPDC), functionalized red blood cell membrane (RBCM), has the increased solubility, utilized biocompatibility, and aggravated tumor penetration of ICA. In this study, we constructed the iRGD functionalized RBCM mimetic targeted ICA-loaded nanoparticles (iRINPs) and explored the anti-tumor effect of iRINPs against lung cancer with biochemical and behavioral analysis. The results suggested that iRINPs showed improved biocompatibility and stability, and reduced phagocytic uptakes by macrophages. Besides, the modification of iRGD significantly improved the targeting ability of iRINPs. In vitro and in vivo the treatment effects and safety assays showed that iRINPs attained better therapeutic effects than ICA by inhibiting A549 cell migration, proliferation and invasion, as well as reducing side effects of ICA. Overall, we expected that the new bionic nanocarriers would be a promising nano-platform for ICA in the precise therapy of lung cancer.

1α,25(OH)2D3(VD3) promotes Raddeanin A-induced anti-proliferative effects on HeLa cell apoptosis and autophagy through negative regulation of HPV18E6-E7/PD-L1/VDR axis.

Raddeanin A (RA) has indicated suppressive effects on various human tumor cells, and insufficient vitamin D was associated with human papillomavirus (HPV) persistence and gynecological tumors. However, combined effects of RA and vitamin D on HPV-positive cells remain elusive. Herein, we aimed to investigate the combined effects of RA and 1ɑ,25(OH)2D3 (VD3) on cellular viability and modulation of HPV18E6/E7, programmed cell death 1 ligand (PD-L1) and vitamin D receptor (VDR) expression in HeLa cells in vitro. HeLa cells were treated with RA alone or VD3 combined with RA. Cell viability was measured using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), and apoptosis was detected by flow cytometry. Real-time PCR (qRT-PCR) and Western blot were used to determine the gene/protein expression levels. The autophagosomes were observed by Transmission electron microscopy (TEM). The result showed that cell viability was inhibited by RA, and apoptosis in HeLa cells treated with RA was elevated accordingly. The expression of Bax, Cleaved-caspase-3, Cleaved-caspase-9 and Cleaved-PARP increased, and Bcl-2 decreased. The autophagy was induced by RA, as evidenced by elevated autophagosomes and the increased LC3-II/I ratio and Beclin-1. The expression of HPV18E6/E7, PD-L1 and VDR was reduced by RA. Moreover, RA combined with VD3 had a stronger effect on HeLa cells than RA alone. In conclusion, RA inhibits HeLa proliferation and induces apoptosis and autophagy via suppressing HPV18E6/E7, PD-L1 and VDR, and VD3 showed reinforced effects of RA on HeLa cells. Therefore, combined usage of VD3 with RA might be a potential novel immunotherapy strategy for HPV-related diseases.

First-Principle Insight into Ga-Doped MoS2 for Sensing SO2, SOF2 and SO2F2.

First-principle calculations were carried out to simulate the three decomposition gases (SO2, SOF2, and SO2F2) of sulfur hexafluoride (SF6) on Ga-doped MoS2 (Ga-MoS2) monolayer. Based on density functional theory (DFT), pure MoS2 and multiple gas molecules (SF6, SO2, SOF2, and SO2F2) were built and optimized to the most stable structure. Four types of Ga-doped positions were considered and it was found that Ga dopant preferred to be adsorbed by the top of Mo atom (TMo). For the best adsorption effect, two ways of SO2, SOF2, and SO2F2 to approach the doping model were compared and the most favorable mode was selected. The adsorption parameters of Ga-MoS2 and intrinsic MoS2 were calculated to analyze adsorption properties of Ga-MoS2 towards three gases. These analyses suggested that Ga-MoS2 could be a good gas-sensing material for SO2 and SO2F2, while it was not suitable for SOF2 sensing due to its weak adsorption. This work provides a theoretical basis for the development of Ga-MoS2 materials with the hope that it can be used as a good gas-sensing material for electrical equipment.

Exosomes as drug carriers for cancer therapy and challenges regarding exosome uptake.

With the development of biomedicine, exosomes are rapidly developing as a new therapy for tumors. As biological carriers, exosomes possess biological activity and can transport their contents between cells. The contents are natural or artificially loaded with biomolecules or chemical drugs. Exosomes deliver biomolecules or chemical drugs into the pathological sites of recipient, which can effectively inhibit the progression of tumors. However, the treatments of tumors through the delivery of exosomes are not sufficiently accurate or efficient, and various challenges need to be overcome. Exosomes from different cell sources possess different characteristics, as well as different specificity for various cells. In the future, for the promotion and application of exosomes, it is of great significance to understand how to select appropriate exosomes loaded with biomolecules or chemical drugs for different tumors types, and how to deliver exosomes to recipient cells accurately and efficiently. This review introduces the application and challenges of exosomes as delivery carriers in tumors.

The JAK2/STAT3 pathway inhibitor, AG490, suppresses the abnormal behavior of keloid fibroblasts in vitro.

AG490 is a selective inhibitor of the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. The present study examined its effects on the abnormal behavior of human keloid fibroblasts (HKFs) and evaluated its potential use in the treatment of keloids. Human normal fibroblasts (HNFs) and HKFs were treated with increasing concentrations of AG490. The proliferation of HNFs and HKFs was inhibited by AG490 in both a time­ and concentration­dependent manner by increasing apoptosis and inducing G1 cell cycle arrest. The downregulation of cyclin D1 and connective tissue growth factor (CTGF) expression was associated with a decrease in STAT3 expression in response to AG490. The effects of AG490 on TGF­ß­stimulated fibroblasts, including HNFs, HKFs and hypertrophic scar fibroblasts (HSFs) were also evaluated. The TGF­ß1­stimulated excessive proliferation and CTGF production were markedly inhibited by the application of AG490 in the HNFs, HSFs and HKFs. In addition, the STAT3­specific decoy oligodeoxynucleotides (SODNs) were transfected into HKFs. The invasive ability of the SODN­transfected HKFs was determined and the expression of extracellular matrix components was quantified. Similarly, SODNs blocked the constitutive activation of STAT3. SODNs inhibited the invasion and progression of HKFs, possibly via the upregulation of the expression of tissue inhibitor of metalloproteinase­2 (TIMP­2), and the downregulation of the expression of matrix metalloproteinase­2 (MMP­2) and vascular endothelial growth factor (VEGF). On the whole, the findings of the present study demonstrate that STAT3­specific elimination, such as the application of AG490 and decoy ODNs, may serve as promising therapeutic strategies for the treatment of keloids.

Interference-Aware Subcarrier Allocation for Massive Machine-Type Communication in 5G-Enabled Internet of Things.

Massive machine-type communication (mMTC) is investigated as one of three typical scenes of the 5th-generation (5G) network. In this paper, we propose a 5G-enabled internet of things (IoT) in which some enhanced mobile broadband devices transmit video stream to a centralized controller and some mMTC devices exchange short packet data with adjacent devices via D2D communication to promote inter-device cooperation. Since massive MTC devices have data transmission requirements in 5G-enabled IoT with limited spectrum resources, the subcarrier allocation problem is investigated to maximize the connectivity of mMTC devices subject to the quality of service (QoS) requirement of enhanced Mobile Broadband (eMBB) devices and mMTC devices. To solve the formulated mixed-integer non-linear programming (MINLP) problem, which is NP-hard, an interference-aware subcarrier allocation algorithm for mMTC communication (IASA) is developed to maximize the number of active mMTC devices. Finally, the performance of the proposed algorithm is evaluated by simulation. Numerical results demonstrate that the proposed algorithm outperforms the three traditional benchmark methods, which significantly improves the utilization of the uplink spectrum. This indicates that the proposed IASA algorithm provides a better solution for IoT application.

[Pathogenic role of leukotriene B4 in pulmonary microvascular endothelial cell hyper- permeability induced by one lung ventilation in rabbits].

OBJECTIVE: To elucidate the pathogenic role of leukotriene B4 (LTB4) in increased pulmonary microvascular endothelial cell permeability induced by one lung ventilation (OLV) in rabbits. METHODS: Forty-eight healthy Japanese white rabbits were randomly divided into control group (group C), saline pretreatment group (group S), bestatin (a leukotriene A4 hydrolase (LTA4H) inhibitor) plus saline pretreatment group (group B), OLV group (group O), saline pretreatment plus OLV group (group SO) and bestatin plus saline pretreatment with OLV group (group BO). ELISA was used to detect LTB4 content in the lung tissues, and LTA4H and phospholipase Cεl (PLCEl) expressions were examined by Western blotting and quantitative PCR. The wet/dry weight (W/D) ratio of the lung, lung permeability index and the expressions of myosin light chain kinase (MLCK) protein and mRNA in the lung tissues were determined to evaluate the permeability of the pulmonary microvascular endothelial cells (PMVECs). The severities of lung injury were evaluated by lung histomorphological scores. RESULTS: No significant differences were found among groups C, S and B except that LTA4H expressions was significantly lower in group B than in groups C and S (P<0.05). OLV significantly increased the expressions of LTA4H (P<0.05) and resulted in LTB4 overproduction in the lungs (P<0.05) accompanied by significantly enhanced PLCE1 expression and PMVEC permeability (P<0.05). Pretreatment with bestatin, significantly reduced the expression of LTA4H and LTB4 production (P<0.05) and down-regulated the expression of PLCE1 in the lungs of the rabbits receiving OLV (P<0.05). CONCLUSION: Bestatin plays a protective role in OLV-induced rabbit lung injury by downregulating LTA4H to reduce the production of LTB4 in the lungs. LTB4 can increase PMVEC permeability by up-regulating PLCE1 expression in rabbits with OLV-induced lung injury.

Ruthenium-Catalyzed Site-Selective Intramolecular Silylation of Primary C-H Bonds for Synthesis of Sila-Heterocycles.

Incorporating the silicon element into bioactive organic molecules has received increasing attention in medicinal chemistry. Moreover, organosilanes are valuable synthetic intermediates for fine chemicals and materials. Transition metal-catalyzed C-H silylation has become an important strategy for C-Si bond formations. However, despite the great advances in aromatic C(sp2)-H bond silylations, catalytic methods for aliphatic C(sp3)-H bond silylations are relatively rare. Here we report a pincer ruthenium catalyst for intramolecular silylations of various primary C(sp3)-H bonds adjacent to heteroatoms (O, N, Si, Ge), including the first intramolecular silylations of C-H bonds α to O, N, and Ge. This method provides a general, synthetically efficient approach to novel classes of Si-containing five-membered [1,3]-sila-heterocycles, including oxasilolanes, azasilolanes, disila-heterocycles, and germasilolane. The trend in the reactivity of five classes of C(sp3)-H bonds toward the Ru-catalyzed silylation is elucidated. Mechanistic studies indicate that the rate-determining step is the C-H bond cleavage involving a ruthenium silyl complex as the key intermediate, while a η2-silene ruthenium hydride species is determined to be an off-cycle intermediate.

[Application value of Provider-Initiated HIV Testing and Counseling in dermatology].

OBJECTIVE: To explore the clinical application value of Provider-Initiated HIV Testing and Counseling (PITC) by analyzing the positive rate of HIV tests for people in need of PITC and that of routine HIV tests. METHODS: We retrospectively analyzed the demographic and epidemiologic data about the patients seeking PITC services or undergoing routine HIV tests in Nanjing Drum Tower Hospital between January and December 2013. RESULTS: The positive rate of initial HIV screening was 1.98% in the PITC group and 0.24% in the routine test group, while that of confirmed HIV was 0. 40% in the former and 0.07% in the latter, both with statistically significant differences between the two groups (P < 0.01). The positive rate of HIV was markedly higher in males than in females, particularly in the PITC group. CONCLUSION: PITC has a high clinical value in HIV detection for targeted subjects and therefore deserves general application in dermatology.

The copper-catalyzed aerobic oxidative amidation of tertiary amines.

A general and efficient method for the synthesis of tertiary amides has been developed via the copper-catalyzed aerobic oxidative amidation of tertiary amines. Due to the use of the O2 oxidant, various functional groups were well tolerated under the present conditions. Extensive substrates studies demonstrated its potential as a practical approach for the synthesis of tertiary amides.

Sodium channel point mutations associated with pyrethroid resistance in Chinese strains of Culex pipiens quinquefasciatus (Diptera: Culicidae).

BACKGROUND: Pesticide resistance due to sodium channel point mutations has been well documented in many mosquito species. METHODS: We tested the resistance of six, wild, Chinese populations of the mosquito Culex pipiens quinquefasciatus to deltamethrin and cyhalothrin. The full length of the sodium channel gene was cloned and sequenced from a pooled sample of mosquitoes from each population. RESULTS: Seven amino acid alterations were found (V250M, R436K, M943V, I973T, L1035F, L1035S and E1901D). Correlation between the frequencies of these mutations and the level of pesticide resistance (LC50) associated with them indicates that those at position L1035 (corresponding to position L1014F in the house fly, Musca domestica; GenBank Accession No.: X96668) are associated with resistance to deltamethrin and cyhalothrin. The frequency of the L1035F mutation was significantly correlated with resistance to deltamethrin (R2 = 0.536, P = 0.049) and cyhalothrin (R2 = 0.626, P = 0.030), and the combined frequency of the L1035F and L1035S mutations was significantly correlated with resistance to both deltamethrin (R2 = 0.661, P = 0.025), and cyhalothrin (R2 = 0.803, P = 0.008). None of the other mutations were correlated with either deltamethrin or cyhalothrin resistance. Interestingly, an HWE test indicated significant linkage between the M943V and I973T mutations (P < 0.01), but further research is required to determine the biological significance of this linkage. CONCLUSIONS: Identifying these mutations may be of practical benefit to the development of pesticide resistance management programs.

[Relationship between high incidence of lung cancer among non-smoking women and silica in C1 bituminous coal in Xuanwei, Yunnan Province, China].

OBJECTIVE: To measure the content of silica in C1 bituminous coal and its combustion products in the high-incidence area of lung cancer in Xuanwei, Yunnan Province, China and to investigate the relationship between high incidence of lung cancer among non-smoking women and silica produced naturally in C1 bituminous coal in Xuan Wei. METHODS: The C1 bituminous coal widely used in the high-incidence area of lung cancer in Xuanwei was selected as experiment group, while the C2+1, K7, and M30 bituminous coal that was mined and used in the low-incidence area of lung cancer in Xuanwei for more than 10 years were selected as control group. Fourteen paraffin-embedded cancer tissue samples from the non-smoking women with non-small cell lung cancer who were born in Xuanwei and were at least the 3rd generation of the family living there were collected from the department of pathology, the third affiliated hospital of kunming medical university (tumor hospital of yunnan province). Titrimetric potassium silicofluoride method was used to measure the content of silica in raw coal and its bottom ashes in 20 samples from the experimental group and control group. Scanning electron microscopy (SEM) was used to observe the morphology of silica particles in C1 bituminous coal and its bottom ashes, and scanning electron microscopy coupled with energy dispersive X-ray analyzer (SEM-EDX) was used to analyze the microscopic composition. Transmission electron microscope (TEM) was used to observe the morphology of silica particles in the bottom ashes and coal soot of C1 bituminous coal as well as the lung cancer tissue from the non-smoking women in Xuanwei, and transmission electron microscope coupled with energy dispersive X-ray analyzer (TEM-EDX) was used to analyze the microscopic composition. The silica particles were separated from the coal soot and bottom ashes and characterized by physical method. RESULTS: The silica content in C1 bituminous coal and its bottom ashes was significantly higher than that in C2+1, K7, and M30 bituminous coal (P < 0.05). The bottom ashes of C1 bituminous coal contained a large quantity of silica particles, mostly with microscale sizes. Silica particles were found in the soot of C1 bituminous coal and the lung cancer tissue from non-smoking women in Xuanwei. The silica particles in the bottom ashes were mostly 120 ∼ 500 nm in diameter, had various shapes, and contained such elements as iron, aluminium, calcium, and potassium; the silica particles in the coal soot were mostly nanoscale, ranging from 37 nm to 80 nm in diameter, had various shapes, with some in fibrous form, had non smooth surfaces, and contained such elements as iron, potassium, calcium, aluminium, and sulfur. CONCLUSION: In Xuanwei, the incidence of lung cancer among non-smoking women is high in the area where silica-rich C1 bituminous coal is produced. There are silica particles enriched in both the combustion products (coal soot and bottom ashes) of C1 bituminous coal and the cancer tissue from the non-smoking women with non-small cell lung cancer, with similar morphology and microscopic composition. We hypothesize that the silica particles from combusted C1 bituminous coal in Xuanwei are mixed with indoor air and inhaled along with other suspended particles.

[Serum and lung tissue selenium measurements in subjects with lung cancer from Xuanwei, China].

BACKGROUND AND OBJECTIVE: Xuanwei is an area of the highest incidence and mortality with lung cancer in China. The aim of this study is to determine serum selenium concentrations in lung cancer patients from Xuanwei as well as selenium levels of cancerous tissues, cancer-adjacent pulmonary tissues, and normal pulmonary lung tissues from lung cancer patients, and the relationship between selenium and the high incidence of lung cancer in Xuanwei. METHODS: One hundred and twenty female adults from Xuanwei were enrolled in the study (60 lung cancer patients and 60 with non-tumor and non-respiratory diseases, respectively) and blood samples were collected. Sixty fresh cancerous tissues and their adjacent as well as normal tissues were collected (31 samples from lung cancer patients living in Xuanwei for more than 2 years and 29 from patients in other regions of Yunnan Province outside of Xuanwei, respectively). Serum and tissue selenium concentrations were assayed using a fluorometric method. RESULTS: Women with lung cancer had a mean serum selenium value (55.22 µg/L±13.34 µg/L) of averagely 8.47%, significantly lower than that in subjects with non-tumor and non-respiratory disease controls (60.33 µg/L±13.82 µg/L)(P < 0.05). Selenium concentrations in the tumor tissues (0.105 µg/g±0.034 µg/g) were statistically lower than that of normal ones (0.140 µg/g±0.048 µg/g)(P < 0.05) from lung cancer patients in Xuanwei. Statistical differences had not been found between the cases from Xuanwei and non-Xuanwei district, adenocarcinoma and squamous cell carcinoma, among Stage I, Stage II, stage III groups. CONCLUSIONS: Lower serum selenium state was negatively related to the incidence of lung cancer in Xuanwei. It was likely that lower selenium level of lung tissues was potential risk factor to lead to lung cancer.

Immunization status and risk factors of migrant children in densely populated areas of Beijing, China.

OBJECTIVE: To properly evaluate the immunization status and determine risk factors of migrant children in 23 densely populated towns and townships in Beijing. METHODS: A household cluster sampling survey was implemented and standard face-to-face interviews were conducted with 1820 migrant children aged 12-35 months. Demographic characteristics of the child and primary caregiver, the child's migrant characteristics, the primary caregiver's knowledge and attitude toward immunization, information about immunization services provided by the local clinic, and the child's immunization history were obtained. Weighted up-to-date (UTD) and age-appropriate immunization rates for the following four vaccines were assessed: three doses of diphtheria, tetanus and pertussis combined vaccine (DTP); three doses of oral poliomyelitis vaccine (OPV); three doses of hepatitis B vaccine (HepB); and one dose of Measles-containing vaccine (MCV). Weighted UTD and age-appropriate immunization rates for the overall series of these four vaccines (the 3:3:3:1 immunization series) were also estimated. Risk factors for not being UTD, being invalid and being delayed for the 3:3:3:1 immunization series were explored using both single-level and multi-level multinomial logistic regression models. RESULTS: For each antigen, the weighted UTD immunization rate was above 83%, but the age-appropriate immunization coverages for HepB, OPV, DPT, and MCV were only 45.6%, 49.6%, 50.8% and 54.7%, respectively. The 1st dose was most likely to be invalid or delayed within HepB, OPV and DPT series. For the 3:3:3:1 immunization series, the weighted UTD and age-appropriate immunization rates were 78.1% and 20.5%, respectively. Immunization status of migrant children tended to be homogenous within a village and therefore, multi-level model was more appropriate for assessing risk factors. Besides demographic characteristics, several other factors were significantly associated with age-appropriate immunization coverage. These factors included: the child's migrant characteristics; the primary caregiver's awareness of the importance of vaccination, and outreach services provided by immunization clinics including notification services and supplementary immunization activities (SIAs). The frequency and duration of clinical immunization sessions significantly influenced the UTD immunization rate but not the age-appropriate immunization rate. The degree of the primary caregiver's satisfaction with clinic services and convenience to vaccination clinic had no impact on the child's immunization status. CONCLUSION: Alarmingly low age-appropriate immunization coverage of migrant children in densely populated areas demanded immediate intervention. Community context was an important factor to a migrant child's vaccination status and should be considered when taking measures. Strategies to strengthen outreach immunization service need to be developed to effectively improve the age-appropriate immunization coverage of migrant children.

Beneficial effect of Bupleurum polysaccharides on autoimmune disease induced by Campylobacter jejuni in BALB/c mice.

AIM OF THE STUDY: Radix Bupleuri, is one of the most frequently prescribed crude herbs in the prescriptions of traditional Chinese medicine for the treatment of inflammatory diseases and auto-immune diseases. This study was to determine whether the crude polysaccharides (BPs) isolated from the roots of Bupleurum smithii var. parvifolium, had beneficial effects on autoimmune disease. MATERIALS AND METHODS: BALB/c mice were immunized with CJ-S(131) in Freund's complete adjuvant on day 0, and then boosted on day 14. BPs 15 or 30 mg kg(-1) day(-1), or prednisone 5 mg kg(-1) day(-1) was given to BALB/c mice intragastrically from day 0 to day 34. RESULTS: Treatment with BPs 15 or 30 mg kg(-1) day(-1) for 35 days protected kidney from glomerular injury with reduced immunoglobulin deposition and lowered proteinuria. The increased production of serum autoantibodies and total immunoglobulin G (IgG) was also inhibited. BPs 30 mg kg(-1) day(-1) improved weight loss and spleen swelling when compared with vehicle-treated group. CONCLUSIONS: These findings suggested that Bupleurum polysaccharides had a beneficial effect on systemic lupus erythematosus-like syndroma induced by CJ-S(131) in BALB/c mice.