Improving Implicit Recommender Systems with Auxiliary Data

Most existing recommender systems leverage the primary feedback only, despite the fact that users also generate a large amount of auxiliary feedback. These feedback usually indicate different user preferences when comparing to the primary feedback directly used to optimize the system performance. For example, in E-commerce sites, view data is easily accessible, which provides a valuable yet weaker signal than the primary feedback of purchase. In this work, we improve implicit feedback-based recommender systems (dubbed Implicit Recommender Systems ) by integrating auxiliary view data into matrix factorization (MF). To exploit different preference levels, we propose both pointwise and pairwise models in terms of how to leverage users’ viewing behaviors. The latter model learns the pairwise ranking relations among purchased, viewed, and non-viewed interactions, being more effective and flexible than the former pointwise MF method. However, such a pairwise formulation poses a computational efficiency problem in learning the model. To address this problem, we design a new learning algorithm based on the element-wise Alternating Least Squares  (eALS) learner. Notably, our designed algorithm can efficiently learn model parameters from the whole user-item matrix (including all missing data), with a rather low time complexity that is dependent on the observed data only. Extensive experiments on two real-world datasets demonstrate that our method outperforms several state-of-the-art MF methods by 6.43%∼ 6.75%. Our implementation is available at https://github.com/dingjingtao/Auxiliary_enhanced_ALS.

Cisplatin-mediated down-regulation of miR-145 contributes to up-regulation of PD-L1 via the c-Myc transcription factor in cisplatin-resistant ovarian carcinoma cells

Immune tolerance is one of the leading causes of chemotherapy resistance in carcinoma cases. Studies have shown that programmed cell death ligand-1 (PD-L1), an inhibitory molecule expressed by cancer cells, plays a significant role in immune tolerance through the induction of T cell dysfunction. The results of our RNA sequencing in previous studies revealed that microRNA-145 (miR-145), which is known to be down-regulated by cisplatin in cisplatin-resistant ovarian cancer cells, also represses gene PD-L1 expression. However, the mechanism by which miR-145 contributes to regulate PD-L1 expression in cisplatin resistance of ovarian cancer is yet to be fully understood. Here, we show that cisplatin-mediated miR-145 down-regulation increased PD-L1 expression via targeting the c-Myc transcription factor, thereby inducing T cell apoptosis in vitro. We also report that expression of miR-145 is negatively correlated with PD-L1 expression in human ovarian cancer tissues, malignant grades and the recurrent risks of ovarian cancer after chemotherapy. In summary, our findings suggest that the miR-145/c-Myc/PD-L1 axis contributes to cisplatin resistance in ovarian cancer and support that miR-145 might act as an adjuvant therapeutic target in chemotherapy of ovarian cancer.

GluR1 protects hypoxic ischemic brain damage via activating Akt signaling pathway in neonatal rats

OBJECTIVE

To investigate the role of glutamic acid receptor 1 (GluR1) in hypoxic-ischemic brain damage (HIBD) in neonatal rats and its underlying mechanism.

MATERIALS AND METHODS

7-day-old neonatal rats received right common carotid artery (CCA) ligation for the establishment of HIBD. After the operation, rats were sacrificed at different time points (0, 4, 6, 12, 24, 48, and 72 h), respectively. Meanwhile, rats in Sham group underwent similar procedures without ligation. Lentivirus-GLUR1-shRNA (LV-GLUR1 shRNA group) was constructed and then transfected into the right lateral ventricles of rats to inhibit GluR1 in vivo. Rats received LV-control injection were selected in the control group (LV-control group). After injection of Lentivirus-GLUR1-shRNA, CCA ligation was performed in rats for HIBD construction. Western blot was performed to detect the protein levels of GLUR1, Akt, p-Akt, and vascular endothelial growth factor (VEGF) in brain tissues. Cell apoptosis was measured by TUNEL staining assay.

RESULTS

After hypoxic ischemia (HI), GLUR1 expression increased gradually and reached a peak at 24 h. Meanwhile, p-Akt expression increased immediately and then gradually decreased. 24 h later, p-Akt expression increased again and peaked at 48 h. VEGF expression increased at 4 h after HI and reached a peak at 12 h. The expression levels of GLUR1, p-Akt, and VEGF in the brain tissues derived from rats transfected with LV-GLUR1 shRNA significantly decreased at both 4 h and 24 h after HI. In addition, results indicated that cell apoptosis was enhanced after LV-GLUR1 shRNA administration, suggesting the role of GLUR1 in protecting against HIBD.

CONCLUSIONS

GLUR1 exhibits a remarkable protective role in HIBD, which may be related to the activation of the Akt signaling pathway and the upregulation of VEGF after HI.

[Incidence of chronic obstructive pulmonary disease and pneumoconiosis in different occupational positions among populations from jinchang cohort]

Objective: To investigate the incidence and rank of chronic obstructive pulmonary disease and pneumoconiosis to the workers in different occupational positions in Jinchang Cohort. Methods: In January 2014, a cohort of follow-up population in jinchang city was taken as the research object, 17843 individuals among follow-up populations in Jinchang Cohort Study, removed the individuals with chronic obstructive pulmonary disease and pneumoconiosis before 2013, and counted the new incidence individuals diagnosed by the A-Class hospital in Grade III in Jinchang City, Gansu Province, as the investigation objects to investigate the incidence rate & rank of chronic obstructive pulmonary disease and pneumoconiosis. The statistical significance was tested by chi-square test. Results: The 2-year incidence rate of Chronic Obstructive Pulmonary Disease and Pneumoconiosis in the population of Jinchang Cohort Study were 11.60‰, 13.51‰ for male and 8.46‰ for female. the ranks of 2-year incidence rates of chronic bronchitis, emphysema, pneumoconiosis and other phenotypes of chronic obstructive pulmonary disease were 7.06‰、3.42‰、0.84‰、0.34‰, respectively. Incidence rate of chronic bronchitis among administrators and executive staffs were 10.45‰; incidence rate of chronic bronchitis among service staffs were 10.45‰; incidence rate of pneumoconiosis among mining staffs were 3.44‰. Conclusion: The first incidence rank of chronic obstructive pulmonary disease and pneumoconiosis in Jinchang cohort is chronic bronchitis, and the risk factors are smoking and occupational exposure.

Study of the morphological changes of copper and zinc during pig manure composting with addition of biochar and a microbial agent

Intensive and unregulated use of feed additives in China has led to high levels of heavy metals such as copper and zinc in fertilizers, considerable quantities of which find their way into the environment. Studies have shown that composting could significantly decrease the bioavailability of heavy metals. This study was to investigate the effects of addition of biochar and a microbial agent on the morphological changes in copper and zinc during composting. Results show that treatment T8 successfully immobilized 70.36% of copper as a result of biochar addition. Treatment T3 successfully immobilized 40.76% of zinc; transformation of zinc to a higher stable state was found to be closely related to the formation of fulvic and humic acids. Results of fluorescence spectrum analysis also corroborate that the conversion of copper and zinc to forms with higher stability was associated with the formation of fulvic and humic acid-like substances.

[Analysis on diagnosis rate of chronic kidney disease in hospitalized pediatric patients]

Objective: To analyze diagnosis rate of chronic kidney disease (CKD) in hospitalized pediatric patients in a single center and understand pediatricians' awareness of CKD. Methods: This was a cross-sectional study. Children who were admitted to the Division of Pediatric Nephrology, Peking University First Hospital from January 1, 2008 to December 31, 2017 and met the diagnostic criteria of CKD (kidney disease: improving global outcomes 2012 guideline) were recruited. A total of 4 472 cases were enrolled. Original CKD diagnosis was collected from the home page of medical records. Actual CKD diagnosis was validated and corrected by reviewing medical records and recalculating glomerular filtration rate. The diagnosis rate and influencing factors of pediatric CKD, the distribution and etiology of actual CKD were analyzed. The comparison between groups were performed with χ(2) test. Results: In 4 472 cases, there were 3 470 cases in actual CKD stage 1, among which only 24 cases were in original CKD stage 1. There were 543 cases in actual CKD stage 2-3, among which only 181 cases were in original CKD stage 2-3. Three hundred and one cases were in actual CKD stage 4-5, including 290 cases in original CKD stage 4-5. In addition, there were 43 cases with unknown CKD stage and 115 cases with acute kidney injury. Compared to original CKD diagnosis, the diagnosis rates of CKD stage 1-5 were 0.7% (24/3 470), 16.7% (58/348), 63.1% (123/195), 90.7% (78/86) and 98.6% (212/215), respectively. The proportions of actual CKD stage 1-5 were 80.4% (3 470/4 314), 8.1% (348/4 314), 4.5% (195/4 314), 2.0% (86/4 314) and 5.0% (215/4 314). The etiology of actual CKD included primary glomerular disease (62.2%, 2 686/4 314), secondary glomerular disease (19.7%, 849/4 314), hereditary kidney disease (9.1%, 391/4 314), congenital abnormalities of the kidney and urinary tract (CAKUT) (3.1%, 135/4 314), tubulointerstitial disease (2.2%, 94/4 314) and etiology uncertain (2.1%, 89/4 314). The leading cause of end stage renal disease was etiology uncertain (31.1%, 67/215), followed by hereditary kidney disease (24.2%, 52/215), CAKUT (16.3%, 35/215) and primary glomerular disease (16.3%, 35/215). Conclusions: Among actual CKD hospitalized pediatric patients, the diagnosis rate of CKD given by physicians at discharge was relatively low, especially patients in earlier CKD stages, which reflected serious lack of physicians' awareness of CKD.

Comparison of size-resolved hygroscopic growth factors of urban aerosol by different methods in Tianjin during a haze episode

Size-resolved hygroscopic growth factors of urban aerosol during a haze episode were measured using a Humidified Tandem Differential Mobility Analyzer (HTDMA) (g_m(RH)). These factors were also derived from size-resolved particulate chemical composition combined with the κ-Köhler theory (g_κ(RH)) and the thermodynamic model ISORROPIA-II running in forward mode (g_iso-f(RH)) and reverse mode (g_iso-r(RH)), respectively. In terms of agreement among these hygroscopic growth factors, g_κ(RH) matched g_m(RH) best, followed by g_iso-r(RH). In contrast, g_iso-f(RH) demonstrated a poorer agreement with g_m(RH). The good consistency among g_m(RH), g_κ(RH), and g_iso-r(RH) was because they only focus on the physical hygroscopic process, whereas g_iso-f(RH) contains not only the direct influence of relative humidity (RH) on particle size but also the influence of gaseous precursor on the particle chemical composition, which indirectly affects the hygroscopicity of the particles. In this sense, size-resolved g_κ(RH) and g_iso-r(RH) in a wide size range are more adequate to investigate the impact of RH on light scattering and aerosol radiative forcing. At RH = 80%, g_κ(RH) for accumulation mode particles was 1.30-1.45 on polluted days and higher than that on clean days (1.2-1.3). Whereas on both polluted and clean days, g_κ(RH) of ultrafine and coarse mode particles were generally lower than 1.25. The strong hygroscopicity of accumulation mode particles observed on polluted days can deteriorate visibility due to their high extinction efficiency.

[Knapp procedure and modified Knapp procedure with Foster suture for the treatment of double elevator palsy]

Objective: To investigate the efficacy of Knapp procedure and modified Knapp procedure with Foster suture in the treatment of double elevator palsy(DEP). Methods: Retrospective study. Twenty-two patients with congenital DEP were underwent Knapp procedure (n=15) and modified Knapp procedure(n=7). The clinical data were retrospectively analyzed, including the preoperative and postoperative vertical deviation in the primary position, ocular motility, and binocular vision. Results: The average vertical deviation in the primary position was (34.7±8.6) prism diopters(PD) before surgery and (6.5±6.5) PD after surgery (t=30.41, P=0.00) in the group underwent Knapp procedure. The mean preoperative and postoperative deviations of the group underwent modified procedure were respectively (38.6±14.6) PD and (5.7±9.3)PD (t=15.33, P=0.00). The mean corrected vertical deviation of the latter (32.8±5.7) PD was greater than that of the former (28.1±3.6) PD(t=-2.39, P=0.03). The mean improved upgaze in the modified group (2.6±0.5) was more obvious than that in the Knapp group (1.9±0.6) (t=2.41, P=0.02). There is no significant difference in the surgical effect on downgaze between two groups (U=43.00, P=0.54). Seven patients having binocular vision with abnormal head posture (AHP) before surgery obtained binocular single vision in the primary position and reading position after operations. AHP disappeared or reduced to less than 5°. The surgical outcomes were satisfied in 72.7% patients. But the patients with ≥40 PD preoperative vertical deviation were under-corrected and needed the further operations. Conclusions: Knapp procedure and modified Knapp procedure with Foster suture were the efficient procedures for treatment of DEP without restriction of ipsilateral inferior rectus. Both procedures can obviously correct the vertical deviation and improve upgaze without remarkable limitation of downgaze, which is good to obtain the binocular single vision in the primary and reading position. The modified procedure has more powerful effect on the corrected vertical deviation and improved upgaze. (Chin J Ophthalmol, 2017, 53: 903-907).

[Prospective study of relationship between metabolic diseases and stroke in Jinchang Cohort]

Objective: To understand the incidence of stroke in the population of Jinchang Cohort and the relationship between metabolic diseases and stroke, and provide scientific evidence for the prevention and treatment of stroke in the population. Methods: The epidemiological investigation data and physical examination data of the 33 042 follow-up participants in Jinchang Cohort were collected for a prospective cohort study. Restricted cubic splines functions was used to analyze the dose-response relationship between metabolic indexes and the risk of stroke incidence. Results: 1) The incidence rate of stroke in Jinchang Cohort was 1.59%, and the standardized incidence rate was 3.99%. 2) Hypertension (male HR=2.20, female HR=4.45) and dyslipidemia (male HR=1.49, female HR=1.79) were the risk factors of stroke incidence in the population and diabetes had influence on the incidence of stroke only in the males (HR=1.79), while obesity had influence only in the females (HR=1.64). The more kinds of metabolic diseases, the higher risk of stroke incidence was. 3) Systolic blood pressure had a non-linear dose-response correlation with the risk of stroke incidence, while diastolic blood pressure had a positive linear correlation with the risk of stroke incidence. Conclusions: The incidence of stroke in Jinchang Cohort population was high compared with both domestic level and oversea level. The patients with metabolic diseases were the population at high-risk for stroke, and more attention should be paid to them in the prevention and treatment of stroke. Diastolic blood pressure might be more closely related to stroke.

[A multicenter study of reference intervals for 15 laboratory parameters in Chinese children]

Objective: To establish comprehensive laboratory reference intervals for Chinese children. Methods: This was a cross-sectional multicenter study. From June 2013 to December 2014, eligible healthy children aged from 6-month to 17-year were enrolled from 20 medical centers with informed consent. They were assessed by physical examination, questionnaire survey and abdominal ultrasound for eligibility. Fasting blood samples were collected and delivered to central laboratory. Measurements of 15 clinical laboratory parameters were performed, including estradiol (E2), testosterone(T), luteinizing hormone(LH), follicle-stimulating hormone(FSH), alanine transaminase(ALT), serum creatinine(Scr), cystatin C, immunoglobulin A(IgA), immunoglobulin G(IgG), immunoglobulin M(IgM), complement (C3, C4), alkaline phosphatase(ALP), uric acid(UA) and creatine kinase(CK). Reference intervals were established according to central 95% confidence intervals for reference population, stratified by age and sex. Results: In total, 2 259 children were enrolled. Finally, 1 648 children were eligible for this study, including 830 boys and 818 girls, at a mean age of 7.4 years. Age- and sex- specific reference intervals have been established for the parameters. Reference intervals of sex hormones increased gradually with age. Concentrations of ALT, cystatin C, ALP and CK were higher in children under 2 years old. Serum levels of sex hormones, creatinine, immunoglobin, CK, ALP and urea increased rapidly in adolescence, with significant sex difference. In addition, reference intervals were variable depending on assay methods. Concentrations of ALT detected by reagents with pyridoxal 5'-phosphate(PLP) were higher than those detected by reagents without PLP. Compared with enzymatic method, Jaffe assay always got higher results of serum creatinine, especially in children younger than 9 years old. Conclusion: This study established age- and sex- specific reference intervals, for 15 clinical laboratory parameters based on defined healthy children.

Isotopic evidence of nitrate sources and its transformations in a human-impacted watershed

The considerable spatial and temporal variabilities of nitrogen (N) processing introduce large uncertainties for quantifying N cycles on a large scale, particularly in plain river network regions with complicated hydrographic connections and mixed multiple N sources. In this paper, the dual isotopes δ15N and δ18O and dissolved anions in regularly collected samples (n = 10) from the studied river, which is one of the most seriously polluted rivers in the plain river network regions of the Taihu Lake catchment, were analyzed to ascertain the main nitrate (NO3-) sources and watershed N processing in the context of monsoon climate. The seasonal variations in precipitation, temperature, and hydrology play key roles in the regulation of the river NO3- concentration, NO3- sources, and watershed N processing. Nitrification of N-containing materials in the soil was possibly the major source of NO3- all year round, especially in the rainy season, whereas manure and sewage significantly contributed to the NO3- load in the Taige River in the dry season. Nitrification and denitrification processes within the area were closely related. The significant negative relationship between the water temperature and δ18O-NO3- values indicated the occurrence of nitrification in the soil throughout the year. By contrast, seasonal variations of denitrification were apparent from May to July with the high soil temperature and moisture, thereby indicating the occurrence of denitrification (22.9%) within the watershed. After the assessment of temporal variations of NO3- sources and watershed N processing, improved environmental management practices can be implemented to protect water resources and prevent further water quality deterioration in human-impacted watersheds.

[Risk factors of gout in Jinchang cohort: a Cox regression analysis]

Objective: To explore the incidence and risk factors of gout in Jinchang cohort and provide scientific evidence for the prevention and control of gout. Methods: People without gout detected by baseline survey in Jinchang cohort were selected as study subjects. All the subjects were followed up through questionnaire interview, physical examination as well as laboratory test from January 24, 2013 to November 24, 2015. Cox regression model was used to analyze the risk factors for gout in Jinchang cohort. In addition, log-linear model was used to analyze the interaction between risk factors. Results: A total of 33 153 subjects were followed up, and there were 277 newly diagnosed gout cases in the cohort. The overall incidence of gout was 0.8%. The incidence of gout in males was higher than that in the females, but the incidence of gout in males and females was similar after the age of 60 years. Cox regression analysis showed that age >40 years (at age 40 to 59 years: HR=2.982, 95%CI: 1.503-5.981; at age 60 to 91 years: HR=2.588, 95%CI: 1.107-6.049), alcohol abuse (HR=2.234, 95% CI: 1.128-4.427), obesity (HR=2.204, 95% CI: 1.216-3.997), diabetes (HR=2.725, 95% CI: 1.500-4.950) and high uric acid (HR=5.963, 95%CI: 3.577-9.943) were risk factors for gout, while weekly beans intake ≥0.25 kg (HR=0.528, 95%CI: 0.345-0.808) and regular physical exercise (HR=0.499, 95% CI: 0.286-0.869) were protective factors for gout. The analysis with log-linear model showed that there were two order effects between the risk factors. Conclusions: Age, beans intake, alcohol abuse, physical exercises, obesity, diabetes and high uric acid were important factors influencing the incidence of gout. It is important to have healthy lifestyle and dietary habits, receive regular health examination to prevent and control the incidence of gout in this cohort.

[Study on the current situation of China's First List of Rare Diseases based on 15 million hospitalizations]

Objective: To investigate and analyze the distribution of 121 diseases of China's First List of Rare Diseases based on hospitalized patients of tertiary hospitals and to explore the current situation of rare diseases in China. Methods: Based on previous data of study from Beijing Society of Rare Diseases, a comparison between China's First List of Rare Diseases and the survey list from the pre-study was performed. Descriptive analysis was carried out on the current situation of rare diseases on hospitalizations in 96 tertiary hospitals from year of 2014 to 2015. Results: Nineteen out of 121 diseases on China's First List of Rare Diseases were not included in the rare diseases survey list of Beijing Society of Rare Diseases. The total number of other 102 rare disease cases was 54 468, accounting for 0.35% of the inpatients during the same period. The top ten most and least cases with rare disease were demonstrated in this study. The number of the top ten most cases was 37 977, accounting for 0.25% of the inpatients during the same period. The number of the top ten least cases was 24, accounting for 0.000 16% of the inpatients during the same period. The top most five types of rare diseases counted on the provinces and municipalities were Beijing, Hunan, Shanghai, Shandong and Guangdong. The top five most cases of rare diseases counted on the provinces and municipalities were Beijing, Shanghai, Guangdong, Shandong and Hubei. The age distribution showed that the cases with rare diseases aged 25-64 years accounted for 45.8%, and the cases in children aged 0-14 accounted for 28.6%. The top ten readmission rate ranged from 28.42% to 64.88%. Conclusions: This study preliminarily investigates the number, type, province and municipality distribution, age distribution, and readmission rate of 121 rare diseases from China's First List of Rare Diseases in the hospitalized patients of tertiary hospitals, which provides important data for registration study, medical and drug policy making and other relevant work on rare diseases in China in the future.

[X-linked Alport syndrome: auditory pathogenic variant features and further genotype-phenotype correlations in female patients]

Objective:To analyze the audiological characteristics of female patients with X-linked Alport syndrome and to explore the relationship between genotype and phenotype in China. Method:The hearing data of 64 females diagnosed as Alport syndrome was reviewed and analyzed. All coding exons of COL4A5 genes were PCR-amplified and sequenced with genomic DNA, or mRNA of COL4A5 gene was RT-PCR amplified and sequenced with skin fibroblast. Result:The 64 cases who were accompanied by hematuria or proteinuria all received pure tone audiometry and acoustic immitance test. The incidence of hearing loss was 20.31% (13/64). The hearing were bilaterally symmetrical sensorineural deafness, most of which were mild and moderate hearing loss. The hearing curve is the groove curve. Among the 64 patients, 42 kinds of DNA variants were detected in 52 cases. Among the patients with hearing loss, 1 of them was 12 years old and the rest were over 35 years old. Mild mutations in 13 cases (10 cases of normal hearing and 3 cases of mild hearing loss) and severe mutations in in 12 cases ( 6 cases of normal hearing and 6 cases of mild to moderate hearing loss) were found in 25 cases over 35 years old. A total of 26 cases were followed up for 2 years or more, of which 7 cases had a downward trend of hearing loss, decreased about 5 dB each year, and there was no significant change in the hearing of the other patients. Conclusion:Mild and moderate hearing impairment, and groove type of audiometric curve are mainly found in Chinese X-linked Alport syndrome in females. Hearing loss occurs at middle-age. The onset time of hearing loss was later than that of the male, and the severity of hearing loss was lighter than that of the male. In the course of follow-up, some patients had a downward trend in hearing, and there was no significant correlation between the hearing phenotype and the genotype.

Oxygen Electromigration and Energy Band Reconstruction Induced by Electrolyte Field Effect at Oxide Interfaces

Electrolyte gating is a powerful means for tuning the carrier density and exploring the resultant modulation of novel properties on solid surfaces. However, the mechanism, especially its effect on the oxygen migration and electrostatic charging at the oxide heterostructures, is still unclear. Here we explore the electrolyte gating on oxygen-deficient interfaces between SrTiO_{3} (STO) crystals and LaAlO_{3} (LAO) overlayer through the measurements of electrical transport, x-ray absorption spectroscopy, and photoluminescence spectra. We found that oxygen vacancies (O_{vac}) were filled selectively and irreversibly after gating due to oxygen electromigration at the amorphous LAO/STO interface, resulting in a reconstruction of its interfacial band structure. Because of the filling of O_{vac}, the amorphous interface also showed an enhanced electron mobility and quantum oscillation of the conductance. Further, the filling effect could be controlled by the degree of the crystallinity of the LAO overlayer by varying the growth temperatures. Our results reveal the different effects induced by electrolyte gating, providing further clues to understand the mechanism of electrolyte gating on buried interfaces and also opening a new avenue for constructing high-mobility oxide interfaces.

[Expression of protein phosphatase 2AC in the brain of mice and Alzheimer's patients]

Objective: To investigate the biological functions of protein phosphatase 2AC(PP2AC) in the brain, and to detect its spatio-temporal expression and its involvement in neurological disorders in the brains of mice and Alzheimer's patients. Methods: Western blot was used to evaluate the expression level of PP2AC in different organs. Immunohistochemical staining was performed to detect the in situ expression levels of PP2AC in the brains of mice and patients, and the pathological changes were confirmed in the brains of patients with Alzheimer's disease. Results: Among all the tested organs in adult mouse, the expression of PP2AC protein was the highest in the brain. From embryonic day 18.5 to postnatal 2-year-old mice, PP2AC exhibited spatio-temporal specific expression in the brains. Furthermore, an age-dependent increased expression in the cerebral cortex at both protein and RNA levels was observed. Compared to control group, PP2AC protein expression was lower in the frontal cortex of Alzheimer's patients. Conclusions: The spatio-temporal specific expression profiles of PP2AC in mouse brain implicate its biological significance. Its diminished expression in the frontal cortex of Alzheimer's disease patients implies that PP2AC plays a potential role in the pathogenesis of Alzheimer's disease.

PIG3 suppresses gastric cancer proliferation by regulating p53- mediated apoptosis

Gastric cancer (GC), the third leading cause of cancer mortality and the fifth most common cancer in the world, still is an important health problem worldwide. P53-inducible gene 3 (PIG3) was initially isolated in an investigation to identify the genes that were induced by p53 in human colorectal cancer cells. PIG3 can also regulate the stability of p53 through suppressing the process of the MDM2-mediated ubiquitination of p53. The aim of this study is to explore the expression level of PIG3 in human GC and further investigate the function and mechanism of PIG3 in human GC. Five cell lines and 30 matched GC tissue samples and adjacent tissue samples were used for this study, and MTT assay, colony formation assay, flow cytometry analysis and Western blot were carried out. Expression of PIG3 was found to be frequently reduced in GC. Restoration of the expression of PIG3 inhibited cell proliferation, induced cell apoptosis and further activated P53 signaling in BGC823 cells. In conclusion, we demonstrated that expression of PIG3 is frequently reduced in GC tissue, and PIG3 suppressed human GC growth through p53- mediated apoptosis. PIG3 may act as a potential diagnostic marker and a potential therapeutic target of GC.

3D Black-Blood Luminal Angiography Derived from High-Resolution MR Vessel Wall Imaging in Detecting MCA Stenosis: A Preliminary Study

BACKGROUND AND PURPOSE

3D high-resolution vessel wall imaging is increasingly used for intracranial arterial diseases. This study compared the diagnostic performance of black-blood luminal angiography derived from 3D vessel wall imaging with source images of vessel wall imaging and TOF-MRA in detecting middle cerebral artery stenosis.

MATERIALS AND METHODS

Sixty-two patients with suspected MCA atherosclerosis underwent TOF-MRA, vessel wall imaging, and CTA. Intracranial black-blood luminal angiography was created from source images of vessel wall imaging using minimum intensity projection. The degree and length of MCA stenosis were measured on source images of vessel wall imaging, TOF-MRA, and black-blood luminal angiography and compared using CTA as a reference standard.

RESULTS

The image quality of black-blood luminal angiography was diagnostic in most patients. The intra- and interobserver agreement for both stenosis degree and length measurements was excellent for black-blood luminal angiography. It was comparable with that of source images of vessel wall imaging in grading stenosis. Compared with TOF-MRA, black-blood luminal angiography showed significantly higher sensitivity for the detection of severe stenosis (89.3% versus 64.3%, P = .039) and higher specificity for the detection of occlusion (95.4% versus 84.6%, P = .039). Lesion length estimated on source images of vessel wall imaging was significantly greater than that measured by CTA and black-blood luminal angiography (P < .001 and P = .010).

CONCLUSIONS

Black-blood luminal angiography is better than TOF-MRA in detecting severe stenosis and occlusion of the MCA. Compared with source images of vessel wall imaging, it is more accurate in evaluating stenosis length. Black-blood luminal angiography can be produced as a derivative from vessel wall imaging and implemented as an adjunct to vessel wall imaging and TOF-MRA without extra acquisition time.

Ultrasensitive detection enabled by nonlinear magnetization of nanomagnetic labels

Geometrically confined magnetic particles due to their unique response to external magnetic fields find a variety of applications, including magnetic guidance, heat and drug delivery, magneto-mechanical actuation, and contrast enhancement. Highly sensitive detection and imaging techniques based on the nonlinear properties of nanomagnets were recently proposed as innovative strong-translational potential methods applicable in complex, often opaque, biological systems. Here we report on the significant enhancement of the detection capability using optical-lithography-defined, ferromagnetic iron-nickel alloy disk-shaped particles. We show that an irreversible transition between strongly non-collinear (vortex) and single domain states, driven by an alternating magnetic field, translates into a nonlinear magnetic response that enables ultrasensitive detection of these particles. The record sensitivity of ∼3.5 × 10-9 emu, which is equivalent to ∼39 pg of magnetic material is demonstrated at room temperature for arrays of patterned disks. We also show that unbound disks suspended in the aqueous buffer can be successfully detected and quantified in real-time when administered into a live animal allowing for tracing of their biodistribution. The use of nanoscale ferromagnetic particles with engineered nonlinear properties opens prospects for further enhancing the sensitivity, scalability, and tunability of noise-free magnetic tag detection in high-background environments for various applications spanning from biosensing and medical imaging to anti-counterfeiting technologies.

[Association between fatty liver and type 2 diabetes in the baseline population of Jinchang Cohort]

Objective: To explore the association between fatty liver and type 2 diabetes mellitus (T2DM) in the baseline-population of Jinchang cohort study. Methods: Data from all the participants involved in the baseline-population of Jinchang cohort study was used, to compare the risks of T2DM in fatty liver and non fatty liver groups and to explore the interaction between family history or fatty liver of diabetes and the prevalence of T2DM. Results: Among all the 46 861 participants, 10 574 were diagnosed as having fatty liver (22.56%), with the standardized rate as 20.66%. Another 3 818 participants were diagnosed as having T2DM (8.15%) with standardized rate as 6.90%. The prevalence of T2DM increased in parallel with the increase of age (trend χ(2)=2 833.671, trend P<0.001). The prevalence of T2DM in the fatty liver group was significantly higher than that in the non-fatty liver group, both in men or women and in the overall population. Compared with the group of non-fatty liver, the risks of T2DM in fatty liver group were seen 1.78 times higher in males, 2.33 times in women and 2.10 times in the overall population, after adjustment for factors as age, levels of education, smoking, drinking, physical exercise, BMI, family history of diabetes and some metabolic indicators (pressure, TC, TG, uric acid, ALT, AST, gamma-glutamyl transferase). Date from the interaction model showed that fatty liver and family history of diabetes present a positive additive interaction on T2DM (RERI=1.18, 95%CI: 0.59-1.78; AP=0.24, 95%CI: 0.14-0.34; S=1.43, 95%CI: 1.21-1.69). Conclusions: Fatty liver could significantly increase the risk of T2DM and a positive additive interaction was also observed between fatty liver and family history of diabetes on T2DM. It was important to strengthen the prevention program on T2DM, in order to effectively control the development of fatty liver.

[Effect of salvianolic acid B on proliferation and apoptosis of human nasal polyps fibroblasts]

Objective:The aim of this study is to discuss the effects and mechanism of salvianolic acid B (SAB) on the proliferation and apoptosis of human nasal polyps fibroblasts (NPFs). Method:The NPFs were treated with SAB at different concentrations (5, 10, 20, 40 μmol/L). CCK-8 assay was used to determine the inhibition of SAB on the proliferation of NPFs and determined the optimum concentration for the following experiments. The NPFs were divided into four groups: a) control group: the cells were cultured in DMEM without TGF-β1 or salvianolic acid B; b) the TGF-β1 group: the cells were cultured in DMEM containing 5 ng/ml TGF-β1; c) the SAB group: the cells were cultured in DMEM containing SAB at the optimum concentration by CCK-8 assay; d) the TGF-β1+SAB treatment groups: the cells were cultured in DMEM containing 5 ng/ml TGF-β1 and SAB at the optimum concentration by CCK-8 assay. MTT assay was used to determine the proliferation of NPFs in four groups. The apoptosis rate was analyzed by Annexin-V FITC/PI double staining. The activities of Caspase-3 were detected with spectrophotometric method. Apoptosis related proteins Bcl-2 and Bax were measured by western blot. Result:CCK-8 assay showed that SAB could inhibite NPFs proliferation in a dose-dependent pattern (P<0.05). The following experiments were carried out with the concentration of salvianolic acid B at 10 μmol/L. MTT results showed that SAB could inhibit the proliferation of NPFs stimulated by TGF-β1 (P<0.01). Annexin-V FITC/PI double staining showed that SAB could induce apoptosis of NPFs (P<0.05). The activities of Caspase-3 were increased with SAB (P<0.05). Western blot results showed that SAB reduced the Bcl-2 protein expression, and increased the Bax protein expression and the ratio of Bax/Bcl-2 (P<0.05). Conclusion:Salvianolic acid B could inhibit proliferation and induce apoptosis of NPFs. Its mechanism may be associated with increasing the activities of Caspase-3 by inhibiting the expression of Bcl-2 protein and promoting the expression of Bax protein.

Methylation pattern variation between goats and rats during the onset of puberty

Puberty is initiated by increased pulsatile gonadotropin-releasing hormone (GnRH) release from the hypothalamus. Epigenetic repression is thought to play a crucial role in the initiation of puberty, although the existence of analogous changes in methylation patterns across species is unclear. We analysed mRNA expression of DNA methyltransferases (DNMTs) and methyl-binding proteins (MBPs) in goats and rats by quantitative real-time PCR (qRT-PCR). DNA methylation profiles of hypothalamic were determined at the pre-pubertal and pubertal stages by bisulphite sequencing. In this study, expression of DNMTs and MBPs mRNA showed different patterns in goats and rats. Global methylation variation was low in goats and rats, and the profile remained stable during puberty. Gene ontology (GO) and Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway analysis revealed the involvement of 62 pathways in puberty in goats and rats including reproduction, type I diabetes mellitus and GnRH signalling pathways and found that Edn3, PTPRN2 and GRID1 showed different methylation patterns during puberty in goats and rats and similar variation patterns for Edn3 and PTPRN2 were showed. These indicated that Edn3 and PTPRN2 would play a role in the timing of puberty. This study provides evidence of the epigenetic control of puberty.

Magnetic resonance imaging quantification and biodistribution of magnetic nanoparticles using T1-enhanced contrast

Magnetic iron oxide nanoparticles have been used for various applications such as in the treatment of iron deficiency, as theranostic agents, and as drug carriers. The effective delivery of magnetic iron oxide nanoparticles into the lesion and iron quantification are vital for in vivo theranostic application. To determine the feasibility of using T₁ contrast to non-invasively quantify and monitor the IONPs in vivo, monodispersed Gd-doped iron oxide nanoparticles (GdIONPs) with 4 nm core size were fabricated and were used as T₁-weighted contrast agents to quantify iron contents based on MRI longitudinal relaxation times (T₁). Signal enhancement in positive T₁ contrast caused by GdIONPs was observed in this work. The in vivo T₁ relaxivity of GdIONPs in a tumor matched well with both in vitro T₁ relaxivity and ICP-MS results, demonstrating that the concentration of iron at the tumor site can be directly read from real-time in vivo MRI T₁ relaxivity. Hence, by using this strategy, the Fe content in the lesion can be accurately monitored based on MRI longitudinal relaxation times, and this may shed light on effective magnetic hyperthermia cancer therapy in future.

Examining the effect of ions and proteins on the heat dissipation of iron oxide nanocrystals

In this paper, the effect and contribution of physiological components like ions and proteins under an applied alternating magnetic field (AMF) towards heat dissipation of superparamagnetic iron oxide nanoparticles (SPIONs) are discussed. Our results have shown that under an applied AMF, magnetic hyperthermia efficiency could be significantly enhanced if SPIONs were suspended in 1× phosphate buffered saline (PBS) compared to a suspension in de-ionized (DI) water. However, no heat enhancement was found when SPIONs were suspended in blood which is an amalgamation of physiological ions and proteins. Closer investigations have revealed that the presence of physiological ions can contribute positively to heating efficiency, and the heating efficiency increases with concentration of ions, ionic mass and solubility. However, the heating efficiency of ions can be suppressed to an insignificant level (comparable with measurement error), in the presence of physiological proteins in 1×PBS. Our electrochemical studies also showed that ionic mobility can be reduced significantly if proteins were present in the solution, thus retarding the heating efficiency.

External Quality Assessment for Rubella Virus RNA Detection Using Armored RNA in China

BACKGROUND

Although tremendous efforts have been made to reduce rubella incidence, there are still 300 new cases of congenital rubella syndrome daily; thus, rubella infections remain one of the leading causes of preventable congenital birth defects. An effective surveillance system, which could be achieved and maintained by using an external quality assessment program, is critical for prevention and control of this disease.

METHODS

Armored RNAs, which are noninfectious and RNase-resistant, were used for encapsulation of the E1 gene of rubella virus and for preparation of a 10-specimen panel for external quality assessment. Thirty-two laboratories across mainland China that used nucleic acid tests for rubella virus RNA detection were included in the external quality assessment program organized by the National Center for Clinical Laboratories of China.

RESULTS

Different kinds of commercial kits were used by the laboratories for nucleic acid extraction and TaqMan real-time reverse-transcription PCR for rubella virus RNA detection; 99.2% sensitivity and 100% specificity were achieved in this external quality assessment program.

CONCLUSIONS

Most of the participating laboratories obtained accurate results for rubella nucleic acid tests, thereby achieving the quality required for regional rubella and congenital rubella syndrome elimination.

[Platysma myocutaneous flaps in reconstruction of defects caused by hypopharyngeal cancer resection]

Objective:To study the method and feasibility in reconstruction of platysma myocutaneous flap of defects caused by hypopharyngeal cancer resection. Method:Twelve cases underwent reconstruction with the platysma myocutaneous flap of hypopharyngeal soft defect were investigated. All cases received 2 times preoperative induction chemotherapy followed by hypopharyngeal cancer resection with laryngeal function preservation and the neck lymph node dissection. Platysma myocutaneous flap was used to repair the hypopharyngeal soft tissue defect. Result:All the flaps survived. Three weeks after surgery, all patients can eat without pharyngeal fistula and dysphagia, but pharyngeal foreign body sensation. Three cases of cough after surgery, improved after training. After postoperative radiotherapy, flap survived without secondary necrosis. Laryngeal function of all cases was retained, and only one case with cannula maintained. Conclusion:Preoperative induction program can effectively reduce the lesion. The placenta myocutaneous flap has rich blood supply, strong anti-infectivity. It is an effective method to repair the hypopharyngeal tissue defect with the placenta myocutaneous flap.

[Comparison between continuous noninvasive hemoglobin monitoring and venous blood hemoglobin monitoring in children with kidney disease]

OBJECTIVE

To assess the correlation and consistency between continuous noninvasive hemoglobin detection and venous blood hemoglobin detection in children with kidney disease, and try to analyze the affecting factors. Try to provide a reference for the monitoring of hemoglobin in children with kidney disease by continuous noninvasive hemoglobin detection technique.

METHODS

Eighty-five inpatient children with kidney disease, 50 boys (58.8%) and 35 girls (41.2%), aged from 3 years old to 18 years old (9.35±4.29) were included finally. Noninvasive hemoglobin monitoring by spectrophotometry (SpHb) was stably read by PRONTO-7, selecting the ring finger of the non handedness as the detection site. And then the venous blood hemoglobin of the same patient was collected in 5 minutes as the true hemoglobin (tHb) by Beckman coulter DXH-800. The data of SpHb and tHb were compared and analyzed using SPSS 17.0 and MedCalc.

RESULTS

Correlation analysis showed data of SpHb and tHb were with significant correlation, the correlation coefficient between SpHb and tHb was 0.85 (P<0.05). Bland-Altman plot points suggested that the mean of differences between SpHb and tHb was -1.3 g/dL. The 95% CI of agreement of SpHb-tHb was -4.2-1.5 g/dL, suggesting that the average measurement result of SpHb was lower than that of tHb. The mean of differences as percent between SpHb and tHb was -9.8%, 95% CI of agreement was (-35.9%, 16.2%) exceeding the acceptable range of true value ±6%. The consistent rate of non-invasive hemoglobin detection and venous blood hemoglobin detection was 31.8%, the 95% CI of consistent rate was (21.7%, 41.9%). The chi square test of the fourfold table showed that the diagnosis of anemia with SpHb was of high sensitivity, but the specificity was low, the false positive rate was high, and the difference was statistically significant (P=0.000).

CONCLUSION

There was a significant correlation between SpHb and tHb in the children with kidney disease. Noninvasive hemoglobin measurement can be used for monitoring of changes of hemoglobin in children with kidney diseases. But the consistency between SpHb and tHb needs to be improved. Noninvasive hemoglobin measurement could not replace the venous hemoglobin measurement. It could not be used for the diagnosis of anemia, and the accuracy of hemoglobin concentration measurement in children with kidney disease should be further explored.

Pharmacokinetics of once daily prolonged-release formulation of tacrolimus in children with primary nephrotic syndrome

OBJECTIVE

Tacrolimus prolonged-release(PR) formulation is a new once-daily formulation of the calcineurin inhibitor tacrolimus, which is currently used in adult liver or kidney transplant patients,and is also gradually widely used in children with nephrotic syndrome.The present study was undertaken to preliminarily investigate the pharmacokinetic characteristics of tacrolimus PR in pediatric nephrotic syndrome recipients.

METHODS

This single-center open-label prospective study was performed in pediatric nephrotic syndrome recipients. Pharmacokinetic samples were collected from eight pediatric subjects with nephrotic syndrome from Department of Pediatric Nephrology in Peking University First Hospital between June and August 2011. They followed administration of single oral doses of tacrolimus PR formulation at 0.02 mg/kg (n=2), 0.05 mg/kg (n=2) and 0.10 mg/kg (n=4). Blood samples were taken before the dose and 1, 2, 4, 6, 8, 10, 12 and 24 h after drug intake. No other medicines or interacting food or drinks were taken during the study period. Blood concentrations were measured using an enzyme multiplied immunoassay technique. Pharmacokinetic analysis was performed using WinNolin Phoenix software Version 6.0(Pharsight, Cary, NC,USA).

RESULTS

The pharmacokinetic data were best described by a non-compartment model. Pharmacokinetic parameters of tacrolimus PR formulation in the 3 ascending doses groups (0.02 mg/kg,0.05 mg/kg and 0.10 mg/kg) were as follows: the maximum drug concentrations (C_max/D) were (1.7±1.0) μg/L, (3.1±1.9) μg/L, (8.0±3.5) μg/L, respectively; Areas under the drug concentration-time curve(AUC_0-∞/D) were (47.2±47.1) h×μg/L, (84.0±13.1) h×μg/L, (175.6±107.1) h×μg/L, respectively; Oral clearance rates were (0.8±0.9) L/(h×kg), (0.4±0.1) L/(h×kg), (1.9±1.3) L/(h×kg), respectively; Body weight normalized distribution volumes were (7.0±3.4) L/kg, (12.4±8.4) L/kg and (73.6±68.6) L/kg, respectively. Both mean C_max normalized level for the administered dose(C_max/D) and mean AUC_0-∞ normalized level for the administered dose (AUC_0-∞/D) were higher in the 0.05 mg/kg dosage group than in the 0.02 and 0.10 mg/kg dosage group. There were two peaks in the drug concentrations in every dose group;a primary peak appeared at the end of about 2 h followed by a small secondary peak at h 12, which was more noticeable in the 0.10 mg/kg dose group than in the two lower dosages.

CONCLUSION

The pharmacokinetic characteristics of tacrolimus PR formulation were initially explored in pediatric patients with nephritic syndrome. The data presented form a basis for subsequent larger scale studies on pharmacokinetics of tacrolimus PR formulation in nephritic syndrome children.