Temporal trends in sleep pattern among Chinese adults between 2010 and 2018: findings from five consecutive nationally representative surveys

OBJECTIVES

This study aimed to comprehensively analyze the time trends in average sleep duration and prevalence of short sleep, poor sleep quality, and high sleep debt among Chinese adults.

STUDY DESIGN

This was a cross-sectional study.

METHODS

The study used nationally representative data from Chinese Family Panel Survey (CFPS) among adults aged ≥18 years. Linear regression and logistic regression were used to calculate P-values for trends across waves, and absolute difference in prevalences were calculated by linear regression. Poisson regression analysis was used to calculate the prevalence ratios of sleep-related problems.

RESULTS

In 2018, the estimated average sleep duration in adults was 7.6 h/d. A shorter sleep duration, higher proportion of short sleep, and poor sleep quality were observed in people aged ≥65 years, women, people with primary school education or below, and residents in Liaoning province. The average sleep duration slightly decreased from 8.2 h/d in 2010 to 7.6 h/d in 2016, and then remained stable from 2016 to 2018. The prevalence of short sleep duration has markedly increased from 11.8% in 2010 to 24.1% in 2016, and then there was a decline in prevalence from 2016 to 2018, although this decrease was not significant. The prevalence of high sleep debt among employed people increased from 6.2% in 2010 to 8.6% in 2018 (absolute difference, 2.4 p.p; P trend = 0.063). In addition, the prevalence of poor sleep quality increased from 15.6% in 2012 to 21.3% in 2018 (absolute difference of 5.7 p.p; P trend<0.001). For all the sleep-related variables, the degree of changes varied by sociodemographic subgroups.

CONCLUSIONS

In this nationally representative survey of the Chinese population, the average sleep duration slightly decreased from 2010 to 2016, and then remained stable from 2016 to 2018. Poor sleep quality, and high sleep debt increased among most of the sociodemographic subgroups. Future studies are needed to understand the drivers of changes in sleep health among Chinese adults.

Nano-hydroxyapatite/Polyamide 66 cage in anterior cervical corpectomy and fusion: a comprehensive systematic review and meta-analysis

OBJECTIVE

This study aimed to conduct a meta-analysis to compare the effectiveness and safety between titanium mesh cage (TMC) and nano-hydroxyapatite/polyamide 66 cage (n-HA/PA66) in the surgical treatment of cervical spondylotic myelopathy (CSM) through anterior cervical corpectomy and fusion (ACCF).

MATERIALS AND METHODS

We implemented a comprehensive search strategy across multiple databases, including Wanfang, China Knowledge Network, China Biomedical Literature Database, Wipu, PubMed, Cochran, Embase, and Web of Science. To ensure a thorough examination of available literature, the databases were searched from their inception to January 2023. Two independent researchers evaluated the quality of the included studies by using established criteria. We used RevMan 5.4 (Review Manager Web, The Cochrane Collaboration, Copenhagen, Denmark) to facilitate data extraction and analysis.

RESULTS

This analysis included seven controlled clinical studies. The meta-analysis results showed no statistically significant differences between the two groups in terms of operating time, intraoperative bleeding, preoperative Japanese Orthopedic Association (JOA) score, preoperative visual analog scale (VAS) score, preoperative and final follow-up C2-7 Cobb angles, and intervertebral fusion rate (p > 0.05). However, a significant difference was observed between the two groups in terms of the final follow-up JOA [MD = 0.77, 95% CI (0.58, 0.97), p < 0.00001], VAS [MD = -0.50, 95% CI (-0.71, -0.30), p < 0.00001], and sedimentation rate [RR = 0.30, 95% CI (0.18, 0.48), p < 0.00001].

CONCLUSIONS

The use of n-HA/PA66 in ACCF for treating CSM is safe and effective treatment with positive clinical efficacy. In addition, n-HA/PA66 has both effective clinical efficacy and significantly lower fusion settling rates compared to TMC.

Response of sugar metabolism in the cotyledons and roots of Ricinus communis subjected to salt stress

Ricinus communis is an important oilseed crop worldwide and is also considered one of the best potential plants for salt-affected soil improvement in northeast China. However, little is known about photosynthesis and carbohydrate metabolism in this plant, nor the distribution of carbohydrates in cotyledons and roots under salinity stress. In the present study, seedling growth, gas exchange parameters (P_N , E, g_s and C_i ), carbohydrate (fructose, sucrose, glucose, soluble sugar and starch) metabolism and related enzymes and genes were measured in Ricinus plants. Under salt stress, P_N of cotyledons decreased significantly (P < 0.05), resulting in weak photosynthetic capacity. Furthermore, salt stress increased sucrose and glucose content in cotyledons, but decreased soluble sugar and starch content. However, sucrose increased and starch decreased in roots. This may be correlated with the increasing sugar metabolism under salinity, including notable changes in sugar-related enzyme activities (SPS, SuSy, α-amylase and β-amylase) and gene expression of RcINV, RcSUS, RcAmY, RcBAM and RcGBE1. The results suggest that salinity reduces photosynthesis of cotyledons, alters carbohydrate allocation between cotyledons and roots and also promotes starch utilization in cotyledons and starch biosynthesis in roots, leading to a functional imbalance between cotyledons and roots. Together, these findings provide insights into the crucial role of sugar metabolism in improving salt-tolerance of Ricinus during the early seedling growth stage.

Mortality-Air Pollution Associations in Low Exposure Environments (MAPLE): Phase 2

INTRODUCTION

Mortality is associated with long-term exposure to fine particulate matter (particulate matter ≤2.5 μm in aerodynamic diameter; PM2.5), although the magnitude and form of these associations remain poorly understood at lower concentrations. Knowledge gaps include the shape of concentration-response curves and the lowest levels of exposure at which increased risks are evident and the occurrence and extent of associations with specific causes of death. Here, we applied improved estimates of exposure to ambient PM2.5 to national population-based cohorts in Canada, including a stacked cohort of 7.1 million people who responded to census year 1991, 1996, or 2001. The characterization of the shape of the concentration-response relationship for nonaccidental mortality and several specific causes of death at low levels of exposure was the focus of the Mortality-Air Pollution Associations in Low Exposure Environments (MAPLE) Phase 1 report. In the Phase 1 report we reported that associations between outdoor PM2.5 concentrations and nonaccidental mortality were attenuated with the addition of ozone (O3) or a measure of gaseous pollutant oxidant capacity (Ox), which was estimated from O3 and nitrogen dioxide (NO2) concentrations. This was motivated by our interests in understanding both the effects air pollutant mixtures may have on mortality and also the role of O3 as a copollutant that shares common sources and precursor emissions with those of PM2.5. In this Phase 2 report, we further explore the sensitivity of these associations with O3 and Ox, evaluate sensitivity to other factors, such as regional variation, and present ambient PM2.5 concentration-response relationships for specific causes of death.

METHODS

PM2.5 concentrations were estimated at 1 km2 spatial resolution across North America using remote sensing of aerosol optical depth (AOD) combined with chemical transport model (GEOS-Chem) simulations of the AOD:surface PM2.5 mass concentration relationship, land use information, and ground monitoring. These estimates were informed and further refined with collocated measurements of PM2.5 and AOD, including targeted measurements in areas of low PM2.5 concentrations collected at five locations across Canada. Ground measurements of PM2.5 and total suspended particulate matter (TSP) mass concentrations from 1981 to 1999 were used to backcast remote-sensing-based estimates over that same time period, resulting in modeled annual surfaces from 1981 to 2016.

Annual exposures to PM2.5 were then estimated for subjects in several national population-based Canadian cohorts using residential histories derived from annual postal code entries in income tax files. These cohorts included three census-based cohorts: the 1991 Canadian Census Health and Environment Cohort (CanCHEC; 2.5 million respondents), the 1996 CanCHEC (3 million respondents), the 2001 CanCHEC (3 million respondents), and a Stacked CanCHEC where duplicate records of respondents were excluded (Stacked CanCHEC; 7.1 million respondents). The Canadian Community Health Survey (CCHS) mortality cohort (mCCHS), derived from several pooled cycles of the CCHS (540,900 respondents), included additional individual information about health behaviors. Follow-up periods were completed to the end of 2016 for all cohorts. Cox proportional hazard ratios (HRs) were estimated for nonaccidental and other major causes of death using a 10-year moving average exposure and 1-year lag. All models were stratified by age, sex, immigrant status, and where appropriate, census year or survey cycle. Models were further adjusted for income adequacy quintile, visible minority status, Indigenous identity, educational attainment, labor-force status, marital status, occupation, and ecological covariates of community size, airshed, urban form, and four dimensions of the Canadian Marginalization Index (Can-Marg; instability, deprivation, dependency, and ethnic concentration). The mCCHS analyses were also adjusted for individual-level measures of smoking, alcohol consumption, fruit and vegetable consumption, body mass index (BMI), and exercise behavior.

In addition to linear models, the shape of the concentration-response function was investigated using restricted cubic splines (RCS). The number of knots were selected by minimizing the Bayesian Information Criterion (BIC). Two additional models were used to examine the association between nonaccidental mortality and PM2.5. The first is the standard threshold model defined by a transformation of concentration equaling zero if the concentration was less than a specific threshold value and concentration minus the threshold value for concentrations above the threshold. The second additional model was an extension of the Shape Constrained Health Impact Function (SCHIF), the eSCHIF, which converts RCS predictions into functions potentially more suitable for use in health impact assessments. Given the RCS parameter estimates and their covariance matrix, 1,000 realizations of the RCS were simulated at concentrations from the minimum to the maximum concentration, by increments of 0.1 μg/m3. An eSCHIF was then fit to each of these RCS realizations. Thus, 1,000 eSCHIF predictions and uncertainty intervals were determined at each concentration within the total range.

Sensitivity analyses were conducted to examine associations between PM2.5 and mortality when in the presence of, or stratified by tertile of, O3 or Ox. Additionally, associations between PM2.5 and mortality were assessed for sensitivity to lower concentration thresholds, where person-years below a threshold value were assigned the mean exposure within that group. We also examined the sensitivity of the shape of the nonaccidental mortality-PM2.5 association to removal of person-years at or above 12 μg/m3 (the current U.S. National Ambient Air Quality Standard) and 10 μg/m3 (the current Canadian and former [2005] World Health Organization [WHO] guideline, and current WHO Interim Target-4). Finally, differences in the shapes of PM2.5-mortality associations were assessed across broad geographic regions (airsheds) within Canada.

RESULTS

The refined PM2.5 exposure estimates demonstrated improved performance relative to estimates applied previously and in the MAPLE Phase 1 report, with slightly reduced errors, including at lower ranges of concentrations (e.g., for PM2.5 <10 μg/m3).

Positive associations between outdoor PM2.5 concentrations and nonaccidental mortality were consistently observed in all cohorts. In the Stacked CanCHEC analyses (1.3 million deaths), each 10-μg/m3 increase in outdoor PM2.5 concentration corresponded to an HR of 1.084 (95% confidence interval [CI]: 1.073 to 1.096) for nonaccidental mortality. For an interquartile range (IQR) increase in PM2.5 mass concentration of 4.16 μg/m3 and for a mean annual nonaccidental death rate of 92.8 per 10,000 persons (over the 1991-2016 period for cohort participants ages 25-90), this HR corresponds to an additional 31.62 deaths per 100,000 people, which is equivalent to an additional 7,848 deaths per year in Canada, based on the 2016 population. In RCS models, mean HR predictions increased from the minimum concentration of 2.5 μg/m3 to 4.5 μg/m3, flattened from 4.5 μg/m3 to 8.0 μg/m3, then increased for concentrations above 8.0 μg/m3. The threshold model results reflected this pattern with -2 log-likelihood values being equal at 2.5 μg/m3 and 8.0 μg/m3. However, mean threshold model predictions monotonically increased over the concentration range with the lower 95% CI equal to one from 2.5 μg/m3 to 8.0 μg/m3. The RCS model was a superior predictor compared with any of the threshold models, including the linear model.

In the mCCHS cohort analyses inclusion of behavioral covariates did not substantially change the results for both linear and nonlinear models. We examined the sensitivity of the shape of the nonaccidental mortality-PM2.5 association to removal of person-years at or above the current U.S. and Canadian standards of 12 μg/m3 and 10 μg/m3, respectively. In the full cohort and in both restricted cohorts, a steep increase was observed from the minimum concentration of 2.5 μg/m3 to 5 μg/m3. For the full cohort and the <12 μg/m3 cohort the relationship flattened over the 5 to 9 μg/m3 range and then increased above 9 μg/m3. A similar increase was observed for the <10 μg/m3 cohort followed by a clear decline in the magnitude of predictions over the 5 to 9 μg/m3 range and an increase above 9 μg/m3. Together these results suggest that a positive association exists for concentrations >9 μg/m3 with indications of adverse effects on mortality at concentrations as low as 2.5 μg/m3.

Among the other causes of death examined, PM2.5 exposures were consistently associated with an increased hazard of mortality due to ischemic heart disease, respiratory disease, cardiovascular disease, and diabetes across all cohorts. Associations were observed in the Stacked CanCHEC but not in all other cohorts for cerebrovascular disease, pneumonia, and chronic obstructive pulmonary disease (COPD) mortality. No significant associations were observed between mortality and exposure to PM2.5 for heart failure, lung cancer, and kidney failure.

In sensitivity analyses, the addition of O3 and Ox attenuated associations between PM2.5 and mortality. When analyses were stratified by tertiles of copollutants, associations between PM2.5 and mortality were only observed in the highest tertile of O3 or Ox. Across broad regions of Canada, linear HR estimates and the shape of the eSCHIF varied substantially, possibly reflecting underlying differences in air pollutant mixtures not characterized by PM2.5 mass concentrations or the included gaseous pollutants. Sensitivity analyses to assess regional variation in population characteristics and access to healthcare indicated that the observed regional differences in concentration-mortality relationships, specifically the flattening of the concentration-mortality relationship over the 5 to 9 μg/m3 range, was not likely related to variation in the makeup of the cohort or its access to healthcare, lending support to the potential role of spatially varying air pollutant mixtures not sufficiently characterized by PM2.5 mass concentrations.

CONCLUSIONS

In several large, national Canadian cohorts, including a cohort of 7.1 million unique census respondents, associations were observed between exposure to PM2.5 with nonaccidental mortality and several specific causes of death. Associations with nonaccidental mortality were observed using the eSCHIF methodology at concentrations as low as 2.5 μg/m3, and there was no clear evidence in the observed data of a lower threshold, below which PM2.5 was not associated with nonaccidental mortality.

[Dihydromyricetin reverses Herceptin resistance by up-regulating miR-98-5p and inhibiting IGF1R/HER2 dimer formation in SKBR3 cells]

OBJECTIVE

To explore the effect of dihydromyricetin on the expression of miR-98-5p and its mechanism in the development of Herceptin resistance in SKBR3 cells.

METHODS

The expression of IGF2 and miR-98-5p and their interaction relationship were analyzed by bioinformatics analysis through TargetScan online databases. SKBR3 cells and drug-resistant SKBR3-R cells were cultured in cell experiments. Xenograft tumor mice were constructed by SKBR3 and SKBR3-R cells. Proteins were detected by western blotting and immunohistochemistry. Transfected cells were constructed by shRNA lentivirus vectors. RT-QPCR was used to detect RNA. Cell proliferation was detected by MTS method. Cell jnvasion was detected by Transwell assay. Luciferase reporting assays were used to verify RNA interactions. IGF-1R/HER2 heterodimer was determined by immunocoprecipitation.

RESULTS

The expression of IGF2, p-IGF1R, p-Akt and p-S6K in SKBR3-R cells were significantly higher than those in SKBR3 cells, while the expression of PTEN protein was lower in SKBR3-R cells (P < 0.05). IGF1R/HER2 heterodimer in SKBR3-R cells was significantly increased (P < 0.01).The expression of IGF2 and invasion ability were significantly reduced while transfected with miR-98-5p in SKBR3-R cells (P < 0.05), but the IGF2 mRNA were no difference in both cells (P > 0.05). The expression of miR-98-5p was up-regulated and IGF2 was decreased in drug-resistant xenograft tumor mice after feeding with dihydromyricetin, and the tumor became more sensitivity to Herceptin (P < 0.05).

CONCLUSION

Dihydromyricetin could induce the expression of miR-98-5p, which binds to IGF2 mRNA to reduce IGF2 expression, inhibit the IGF-1R/HER2 formation, thereby reversing cell resistance to Herceptin in SKBR3-R cells.

Chondrocyte Adipogenic Differentiation in Softening Osteoarthritic Cartilage

A chondrocyte-to-osteoblast lineage continuum exists in the growth plate. Adipogenic differentiation of chondrocytes in vivo should be investigated. Here, unilateral anterior crossbite (UAC), which can induce osteoarthritic lesions in the temporomandibular joint (TMJ), was applied to 6-wk-old C57BL/6 mice. Matrix loss in TMJ cartilage was obvious, as demonstrated by safranin O staining, and the condylar cartilage elastic modulus values, detected by using atomic force microscopy (AFM), were reduced, indicating cartilage softening that might be linked with loss of the highly charged proteoglycan. By crossing the Rosa26/tdTomato (TdT) mice with Sox9;Cre^ERT2 mice or with Col10;Cre^ERT2 mice, we obtained the Sox9-TdT and Col10-TdT strains, respectively, in which the Sox9- or Col10-expressing cells, accordingly, were labeled by TdT. A few TdT-labeled cells in both strains expressed AdipoQ or DMP-1. The Sox9-TdT⁺AdipoQ⁺ cells were primarily located in the deep zone cartilage and then in the whole cartilage. Col10-TdT⁺AdipoQ⁺ cells, Sox9-TdT⁺DMP-1⁺ cells, and Col10-TdT⁺DMP-1⁺ cells were located in the deep zone region. UAC promoted AdipoQ and DMP-1 expression in cartilage. The percentages of Sox9-TdT⁺AdipoQ⁺ and Col10-TdT⁺AdipoQ⁺ cells to Sox9-TdT⁺ and Col10-TdT⁺ cells, respectively, were increased (both P < 0.05), implying that more chondrocytes were undergoing adipogenic differentiation in the UAC group, the cartilage of which was softened. The percentages of Sox9-TdT⁺DMP-1⁺ and Col10-TdT⁺DMP-1⁺ cells to Sox9-TdT⁺ cells and Col10-TdT⁺ cells, respectively, were increased (both P < 0.05), consistent with our report that UAC enhanced deep zone cartilage calcification, causing stiffening of the deep zone cartilage. Our present data demonstrated that TMJ chondrocyte descendants can become adipogenic in vivo in addition to becoming osteogenic. This potential was promoted in osteoarthritic cartilage, in which deep zone cartilage calcification-associated cartilage stiffening and proteoglycan loss-associated cartilage softening were both stimulated.

Mineral deposition intervention through reduction of phosphorus intake suppresses osteoarthritic lesions in temporomandibular joint

OBJECTIVE

To explore the suppressing impact of low phosphorus intake on osteoarthritic temporomandibular joint and the possible mechanisms of nuclear acid injury in the insulted chondrocytes.

DESIGN

Chondrocytes were loaded with fluid flow shear stress (FFSS) with or without low phosphorus medium. Seventy-two mice (sampled at 3-, 7- and 11-wk, n = 6) and forty-eight rats (sampled at 12-wks for different testing purpose, n = 6) were applied with unilateral anterior crossbite (UAC) with or without low phosphorus diet. In the FFSS model, the Ca and P content, molecules related to nucleic acid degradation and the mineral-producing responses in chondrocytes were detected. The effect of culture dish stiffness on chondrocytes osteogenic differentiation was measured. In the UAC model, the content of Ca and P in serum were tested. The condylar cartilage ossification and stiffness were detected using micro-CT, scanning electron microscope and atomic force microscope.

RESULTS

FFSS induced nucleic acid degradation, Pi accumulation and mineral-producing responses in the cultured chondrocytes, all were alleviated by low P medium. Stiffer dish bottoms promoted the osteogenic differentiation of the cultured chondrocytes. UAC stimulated cartilage degeneration and chondrocytes nucleic acid damage, increased PARP 1 and serum P content, and enhanced ossification and stiffening of the cartilage, all were suppressed by low phosphorus diet (all, P < 0.05).

CONCLUSION

Nucleic acid damage takes a role in phosphorus production in osteoarthritic cartilage, contributing to the enhanced mineralization and stiffness of the cartilage that in turn promotes cartilage degradation, which can be alleviated by low phosphorus intake.

[An optimized protocol of meniscus cell extraction for single-cell RNA sequencing]

OBJECTIVE

To optimize the protocol of meniscus cell extraction to enhance the efficiency of cell suspension preparation and maintain a high cell viability for single-cell RNA sequencing.

METHODS

We compared the efficiency of the routine cell extraction methods (short-time digestion and long-time digestion) and the optimized protocol for obtaining meniscus cell suspensions by evaluating the cell number obtained and the cell viability. Single-cell RNA sequencing datasets were analyzed to evaluate the stability of the cell suspension prepared using the optimized protocol. The reliability of the optimized protocol was assessed by comparing the single-cell RNA sequencing dataset obtained by the optimized protocol with published single-cell RNA sequencing datasets of the meniscus.

RESULTS

The optimized protocol harvested a greater number of cells (over 1×10⁵) than the routine protocols. The cell suspension prepared with the optimized protocol showed a cell viability higher than 80%, the highest among the 3 methods. Analysis of single-cell RNA sequencing datasets showed that the ratio of the mitochondrial genes was below 20% in over 80% of the cells. CD34⁺ cells, MCAM⁺ cells and COL1A1⁺ cells were identified in the datasets. Comparison with the publish datasets showed that the optimized protocol was capable of harvesting COL3A1⁺, COL1A1⁺, MYLK⁺, BMP2⁺, CD93⁺ and CDK1⁺ cells.

CONCLUSION

Single-cell suspension prepared from the meniscus can be stably obtained using the optimized protocol for single-cell RNA sequencing using the 10× Genomics platform.

Mortality-Air Pollution Associations in Low-Exposure Environments (MAPLE): Phase 1

INTRODUCTION

Fine particulate matter (particulate matter ≤2.5 μm in aerodynamic diameter, or PM2.5) is associated with mortality, but the lower range of relevant concentrations is unknown. Novel satellite-derived estimates of outdoor PM2.5 concentrations were applied to several large population-based cohorts, and the shape of the relationship with nonaccidental mortality was characterized, with emphasis on the low concentrations (<12 μg/m3) observed throughout Canada.

METHODS

Annual satellite-derived estimates of outdoor PM2.5 concentrations were developed at 1-km2 spatial resolution across Canada for 2000-2016 and backcasted to 1981 using remote sensing, chemical transport models, and ground monitoring data. Targeted ground-based measurements were conducted to measure the relationship between columnar aerosol optical depth (AOD) and ground-level PM2.5. Both existing and targeted ground-based measurements were analyzed to develop improved exposure data sets for subsequent epidemiological analyses.

Residential histories derived from annual tax records were used to estimate PM2.5 exposures for subjects whose ages ranged from 25 to 90 years. About 8.5 million were from three Canadian Census Health and Environment Cohort (CanCHEC) analytic files and another 540,900 were Canadian Community Health Survey (CCHS) participants. Mortality was linked through the year 2016. Hazard ratios (HR) were estimated with Cox Proportional Hazard models using a 3-year moving average exposure with a 1-year lag, with the year of follow-up as the time axis. All models were stratified by 5-year age groups, sex, and immigrant status. Covariates were based on directed acyclical graphs (DAG), and included contextual variables (airshed, community size, neighborhood dependence, neighborhood deprivation, ethnic concentration, neighborhood instability, and urban form). A second model was examined including the DAG-based covariates as well as all subject-level risk factors (income, education, marital status, indigenous identity, employment status, occupational class, and visible minority status) available in each cohort. Additional subject-level behavioral covariates (fruit and vegetable consumption, leisure exercise frequency, alcohol consumption, smoking, and body mass index [BMI]) were included in the CCHS analysis.

Sensitivity analyses evaluated adjustment for covariates and gaseous copollutants (nitrogen dioxide [NO2] and ozone [O3]), as well as exposure time windows and spatial scales. Estimates were evaluated across strata of age, sex, and immigrant status. The shape of the PM2.5-mortality association was examined by first fitting restricted cubic splines (RCS) with a large number of knots and then fitting the shape-constrained health impact function (SCHIF) to the RCS predictions and their standard errors (SE). This method provides graphical results indicating the RCS predictions, as a nonparametric means of characterizing the concentration-response relationship in detail and the resulting mean SCHIF and accompanying uncertainty as a parametric summary.

Sensitivity analyses were conducted in the CCHS cohort to evaluate the potential influence of unmeasured covariates on air pollution risk estimates. Specifically, survival models with all available risk factors were fit and compared with models that omitted covariates not available in the CanCHEC cohorts. In addition, the PM2.5 risk estimate in the CanCHEC cohort was indirectly adjusted for multiple individual-level risk factors by estimating the association between PM2.5 and these covariates within the CCHS.

RESULTS

Satellite-derived PM2.5 estimates were low and highly correlated with ground monitors. HR estimates (per 10-μg/m3 increase in PM2.5) were similar for the 1991 (1.041, 95% confidence interval [CI]: 1.016-1.066) and 1996 (1.041, 1.024-1.059) CanCHEC cohorts with a larger estimate observed for the 2001 cohort (1.084, 1.060-1.108). The pooled cohort HR estimate was 1.053 (1.041-1.065). In the CCHS an analogous model indicated a HR of 1.13 (95% CI: 1.06-1.21), which was reduced slightly with the addition of behavioral covariates (1.11, 1.04-1.18). In each of the CanCHEC cohorts, the RCS increased rapidly over lower concentrations, slightly declining between the 25th and 75th percentiles and then increasing beyond the 75th percentile. The steepness of the increase in the RCS over lower concentrations diminished as the cohort start date increased. The SCHIFs displayed a supralinear association in each of the three CanCHEC cohorts and in the CCHS cohort.

In sensitivity analyses conducted with the 2001 CanCHEC, longer moving averages (1, 3, and 8 years) and smaller spatial scales (1 km2 vs. 10 km2) of exposure assignment resulted in larger associations between PM2.5 and mortality. In both the CCHS and CanCHEC analyses, the relationship between nonaccidental mortality and PM2.5 was attenuated when O3 or a weighted measure of oxidant gases was included in models. In the CCHS analysis, but not in CanCHEC, PM2.5 HRs were also attenuated by the inclusion of NO2. Application of the indirect adjustment and comparisons within the CCHS analysis suggests that missing data on behavioral risk factors for mortality had little impact on the magnitude of PM2.5-mortality associations. While immigrants displayed improved overall survival compared with those born in Canada, their sensitivity to PM2.5 was similar to or larger than that for nonimmigrants, with differences between immigrants and nonimmigrants decreasing in the more recent cohorts.

CONCLUSIONS

In several large population-based cohorts exposed to low levels of air pollution, consistent associations were observed between PM2.5 and nonaccidental mortality for concentrations as low as 5 μg/m3. This relationship was supralinear with no apparent threshold or sublinear association.

Restoring T-helper 17 cell/regulatory T-cell balance and decreasing disease activity by rapamycin and all-trans retinoic acid in patients with systemic lupus erythematosus

OBJECTIVE

This study aimed to investigate the effect of rapamycin (RAPA) alone or in combination with all-trans retinoic acid (ATRA) on the T-helper 17 (Th17) cell/regulatory T-cell (Treg) balance in patients with systemic lupus erythematosus (SLE) and to evaluate the clinical efficacy.

METHODS

Seventy patients with SLE were enrolled. They were randomly and equally divided into RAPA and RAPA + ATRA groups. The number of Th17 and Treg cells was measured by flow cytometry before and after treatment for 6, 12 and 24 weeks. The SLE Disease Activity Index (SLEDAI) score and the prednisone dose before and after treatment were used to evaluate the efficacy between the two groups.

RESULTS

In both groups, at different time points after treatment, the number of Th17 cells (p = 0.003) and Th17/Treg ratio (p = 0.044) reduced, while the number of Treg cells (p = 0.574) tended to increase. The SLEDAI score and the dose of prednisone decreased significantly (p < 0.001). There was no significant difference in the number of Th17 cells (p = 0.089), Treg cells (p = 0.059), Th17/Treg ratio (p = 0.580), SLEDAI score (p = 0.127) and the dose of prednisone (p = 0.329) between the two groups.

CONCLUSION

Disease activity in SLE patients reduced with RAPA alone or in conjunction with ATRA, reducing glucocorticoid requirement. One of its mechanisms of action may be regulating the Th17/Treg cell balance, which provides a new model for the pathogenesis and potential treatment of SLE.

In utero Exposure to Anesthetics Alters Neuronal Migration Pattern in Developing Cerebral Cortex and Causes Postnatal Behavioral Deficits in Rats

During fetal development, cerebral cortical neurons are generated in the proliferative zone along the ventricles and then migrate to their final positions. To examine the impact of in utero exposure to anesthetics on neuronal migration, we injected pregnant rats with bromodeoxyuridine to label fetal neurons generated at embryonic Day (E) 17 and then randomized these rats to 9 different groups receiving 3 different means of anesthesia (oxygen/control, propofol, isoflurane) for 3 exposure durations (20, 50, 120 min). Histological analysis of brains from 54 pups revealed that significant number of neurons in anesthetized animals failed to acquire their correct cortical position and remained dispersed within inappropriate cortical layers and/or adjacent white matter. Behavioral testing of 86 littermates pointed to abnormalities that correspond to the aberrations in the brain areas that are specifically developing during the E17. In the second set of experiments, fetal brains exposed to isoflurane at E16 had diminished expression of the reelin and glutamic acid decarboxylase 67, proteins critical for neuronal migration. Together, these results call for cautious use of anesthetics during the neuronal migration period in pregnancy and more comprehensive investigation of neurodevelopmental consequences for the fetus and possible consequences later in life.

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.

Influence of Temperature on Susceptibility of CVS. Tifguard and Georgia-06G Peanut to Meloidogyne arenaria

Tifguard was released in 2008 as a peanut cultivar with a high level of resistance to Meloidogyne arenaria. Our objective was to determine the role of temperature on infection and development of M. arenaria in Tifguard compared to that in the nematode susceptible cultivar, Georgia-06G. Temperature affected the rate of nematode infection and development in both Tifguard and Georgia-06G (P ≤ 0.05). In Georgia-06G, egg-laying females were observed 25, 20 or 25 days after inoculation at 28°C, 31°C, and 34°C, respectively. There were greater numbers of nematodes entering roots and acceleration of development in response to 31°C compared with that at 28°C. There was, however, a decrease in the number of nematodes entering roots and their development was retarded at 34°C compared with that occurring at 31°C. Although second-stage juveniles penetrated Tifguard roots, they did not develop further at 28°C or 31°C; however, at 34°C both females, males, and a few egg-laying females of M. arenaria were observed. The optimum temperature for nematode infection and development was 31°C in Georgia-06G. In summary, it is unlikely that high soil temperatures would lessen the effectiveness of the nematode resistance gene in Tifguard.

Clinical, pathological, and demographic factors associated with development of recurrences after surgical resection in elderly patients with neuroendocrine tumors

Background

Incidence of locoregional neuroendocrine tumors (NETs) is rising. However, after curative resection, the patterns and risk factors associated with recurrence remain unknown. Consensus guidelines recommend surveillance every 6-12 months for up to 10 years after surgery for resected, well-differentiated NETs irrespective of patient demographics, site, grade or stage of tumor with few exceptions.

Patients and methods

From the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we identified localized and regional stage NET patients who underwent surgical resection between January 2002 and December 2011. Development of recurrence was identified by capturing at least two claims indicative of metastatic disease until 31 December 2013.

Results

Of the 2366 identified patients (median age 73 years), 369 (16%) developed metastatic disease within 5 years and only an additional 1% developed metastases between years 5 and 10 with the majority dying due to unrelated causes. The 5-year risk of developing metastases (hazard ratio, HR) varied significantly (log-rank P < 0.001) by grade: 9.9% versus 25.9% (2.2) versus 48.1% (4.4) for grades 1, 2, and  ≥ 3, respectively; stage: 10.3% versus 31.1% (2.8) for localized versus regional; primary tumor size: 7.6% versus 15% (1.3) versus 26.6% (1.5) for <1, 1-2, and > 2 cm, respectively; and site: ranging from 11.3% for colon to 23.9% for pancreas.

Conclusions

Contrary to current guidelines, our study suggests that surveillance recommendations should be tailored according to patient and tumor characteristics. Surveillance past 5 years may be avoided in elderly patients with competing morbidities or low risk of recurrence. Pancreatic, lung, higher grade, and regional NETs have a higher risk of recurrence and may be considered for future adjuvant trials.

[The Role of CBS in Injury Time Estimation after Brain Contusion]

OBJECTIVES

To observe the changes of cystathionine β-synthase （CBS） expression in the cerebral cortex after brain contusion at different times.

METHODS

An experimental model of traumatic brain injury （TBI） in mice was established by an improved weight-drop device. Then Western blotting and immunohistochemical examination were used to detect the CBS expression in cerebral cortex around injury at different time points （1 h, 6 h, 12 h, 1 d, 2 d, 3 d, 7 d）.

RESULTS

The results of Western blotting revealed that the expression level of CBS was down-regulated and reached its lowest level at the 3rd days after injury, and then restored to normal level after 7 days. The results of immunohistochemistry showed that CBS was present in the normal brain cortex. CBS expression gradually decreased at the 3rd days after injury, and then restored to normal level after 7 days.

CONCLUSIONS

CBS has the potential to be a reference index for time estimation after brain contusion in forensic practice.

Activation of Aedes aegypti prophenoloxidase-3 and its role in the immune response against entomopathogenic fungi

Serine protease cascade-mediated melanization is an important innate immune response in insects and crustaceans, which involves the proteolytic activation of prophenoloxidase (PPO). In this study, we investigated the role of Aedes aegypti PPO3 in antifungal immune defence. We expressed and purified recombinant PPO3 (rPPO3) in Escherichia coli and demonstrated that rPPO3 was activated by ethanol and, to a lesser extent, by cetylpyridinium chloride. In the presence of Cu²⁺ , rPPO3 exhibited enzyme activity. Immunoblot results revealed that the rPPO3 was cleaved by the haemolymph from immune-challenged mosquitoes or purified Ostrinia furnacalis serine protease 105 in vitro. The cleaved rPPO3 converted dopamine to toxic intermediates that killed fungal conidia of Beauveria bassiana in vitro. In mosquitoes challenged with Be. bassiana, cleavage of rPPO3 produced a 50 kDa phenoloxidase (PO) fragment. Further analysis revealed that the survival rate of mosquitoes with fungal infection increased significantly following injection of rPPO3 into the haemocoel. Taken together, our results suggest that proteolytic cleavage of the mosquito PPO3 plays an important role in the antifungal immune response. This has led to a better understanding of the mechanism of PPO activation in the mosquito and the role of melanization in the antifungal immune response.

Cellular Delivery of Cntf but not Nt-4/5 Prevents Degeneration of Striatal Neurons in a Rodent Model of Huntington's Disease

The delivery of neurotrophic factors to the central nervous system (CNS) has gained considerable attention as a potential treatment strategy for neurodegenerative disorders such as Huntington's disease (HD). In the present study, we directly compared the ability of two neurotrophic factors, ciliary neurotrophic factor (CNTF), and neurotrophin-4/5 (NT-4/5), to prevent the degeneration of striatal neurons following intrastriatal injections of quinolinic acid (QA). Expression vectors containing either the human CNTF or NT-4/5 gene were transfected into a baby hamster kidney fibroblast cell line (BHK). Using a polymeric device, encapsulated BHK-control cells and those secreting either CNTF (BHK-CNTF) or NT-4/5 (BHK-NT-4/5) were transplanted unilaterally into the rat lateral ventricle. Seven days later, the same animals received unilateral injections of QA (225 nmol) into the ipsilateral striatum. Nissl-stained sections demonstrated that the BHK-CNTF cells significantly reduced the volume of striatal damage produced by QA. Quantitative analysis of striatal neurons further demonstrated that both choline acetyltransferase (ChAT)- and glutamic acid decarboxylase (GAD)-immunoreactive neurons were protected by CNTF implants. In contrast, the volume of striatal damage and loss of striatal ChAT and GAD-positive neurons in animals receiving BHK-NT-4/5 implants did not differ from control-implanted animals. These results help better define the scope of neuronal protection that can be afforded following cellular delivery of various neurotrophic factors. Moreover, these data further support the concept that implants of polymer-encapsulated CNTF-releasing cells can be used to protect striatal neurons from excitotoxic damage, and that this strategy may ultimately prove relevant for the treatment of HD.

[Effect of concentrated growth factors on the treatment of degree II furcation involvements of mandibular molars]

OBJECTIVE

Concentrated growth factors (CGF), a new generation of platelet concentrate products, appears to have more abundant growth factors because of its special centrifugation process. However, there are few studies supporting this. This study was designed to evaluate the effect of CGFs in the treatment of II° furcations of mandibular molars.

METHODS

In the present study, thirty-one II° furcation involvements in twenty mandiblular molars were included and randomly divided into two groups. The furcation involvements in the experimental group were treated with bone graft therapy combined with CGFs, and the furcation involvements in the control group were treated with bone graft therapy alone. The clinical examination and cone beam computed tomography (CBCT) were performed at baseline and 1 year post-surgery for the two groups. The changes of clinical and CBCT data at baseline and 1 year post-surgery were compared between the experimental group and the control group.

RESULTS

At baseline, there were no significant differences between the two groups in the probing depth (PD), vertical clinical attachment loss (CAL-V) and horizontal clinical attachment loss (CAL-H): PD (7.36±2.32) mm (the experimental group) vs. (7.53±2.06) mm (the control group); CAL-V (8.69±1.65) mm (the experimental group) vs. (8.81±1.53) mm (the control group); CAL-H (5.24±2.01) mm (the experimental group) vs. (5.35±2.14) mm (the control group). At the end of 1 year post-surgery, the clinical parameters of both groups were significantly improved (P<0.001). For the experimental group, the average vertical attachment gain was (2.78±1.66) mm, and the vertical attachment loss was improved significantly compared with the baseline (P<0.001); the average horizontal attachment gain was (2.10±1.89) mm, and the horizontal attachment loss were improved significantly compared with the baseline (P<0.001). Furthermore, the improvement degree of the experimental group was significantly higher than that of the control group (P<0.001). At baseline, there were no statistical differences in the vertical bone loss (BL-V) or horizontal bone loss (BL-H) between the two groups (P>0.05): BL-V (5.08±2.17) mm (the experimental group) vs. (5.84±2.65) mm (the control group); BL-H (5.85±2.13) mm (the experimental group) vs. (6.01±2.27) mm (the control group). At 1 year post-surgery, both groups showed significant radiographic bone gain at vertical and horizontal directions compared with baseline (P<0.001). For the experimental group, the average vertical radiographic bone gain was (2.20±1.98) mm, the horizontal radiographic bone gain was (2.51±2.18) mm, the vertical and horizontal radiographic bone loss were both significantly reduced compared with the baseline (P<0.001). For the control group, the average vertical radiographic bone gain was (1.89±2.15) mm, the horizontal radiographic bone gain was (1.30±2.47) mm, the vertical and horizontal radiographic bone losses were both significantly reduced compared with the baseline (P<0.001). And the experimental group showed significantly higher bone gain at vertical and horizontal directions compared with the control group (P<0.001).

CONCLUSION

Within the limitation of the present study, CGFs showed positive role in the treatment of II° furcation involvements of mandibular molars.

Knockdown of eIF3a ameliorates cardiac fibrosis by inhibiting the TGF-β1/Smad3 signaling pathway

Cardiac fibroblasts are key effector cells in the pathogenesis of cardiac fibrosis. The eukaryotic translation initiation factor (eIF) 3a is the largest subunit of the eIF3 complex and has been involved in renal fibrosis. However, the precise role of eIF3a in myofibroblast differentiation and cardiac fibrosis remains unknown. Accordingly, in our present study, we tested the expression of eIF3a in transforming growth factor β1 (TGF-β1)-induced rat CFs and found that eIF3a was upregulated in TGF-β1-induced rat CFs. Then the role and mechanism of eIF3a in cardiac fibrosis were explored. Our results found that the eIF3a expression was significantly up-regulated in TGF-β1-induced CFs. Knockdown of eIF3a significantly inhibited TGF-β1-induced CF proliferation, as well as suppressed the expression levels of α-smooth muscle actin (α-SMA) and SM22α. Mechanistically, knockdown of eIF3a attenuated TGF-β1-induced Smad3 activation in CFs. In summary, our present study firstly demonstrated that silencing eIF3a might alleviate TGF-β1-induced cardiac fibrogenesis in CFs by inhibiting Smad3 activation, and suggest that eIF3a may be positioned as a new and promising target for the prevention and treatment of cardiac fibrosis.

A Meta-analysis of Sequential Intravenous/Oral Moxifloxacin Monotherapy for Treatment of Skin and Skin Structure Infections

Moxifloxacin is widely recognized for the treatment of bacterial infections of the respiratory tract such as community acquired pneumonia, acute bacterial sinusitis and acute exacerbations of chronic bronchitis. However, the use of moxifloxacin for skin infections is much valued in recent years. This study is to compare the clinical efficacy and safety of moxifloxacin monotherapy among adults with skin and skin structure infections. The meta-analysis of RCTs is conducted by searching Medline, Embase, Pubmed and the Cochrane Library. 6 RCTs, involving a total of 2608 patients, were included in the meta-analysis. English and Chinese language papers were reviewed. The results of the meta-analysis showed that the moxifloxacin monotherapy has similar clinical cure rate, bacteriological success rates and mortality compared with the control group. The drug-related adverse of moxifloxacin was significantly higher than that in the control group, although the overall incidence of adverse events, serious adverse events, and serious drug-related adverse events were similar between the compared treatment groups. Through this meta-analysis, we can draw a conclusion that moxifloxacin monotherapy has similar effectiveness and relative safety as other recommended antibiotics for the treatment of SSSIs. At the same time, it possesses the superior bacteria eradication rate. The once-daily dosing of moxifloxacin monotherapy may be a useful alternative for other recommended antibiotic therapy.

Post-mortem assessment of the short and long-term effects of the trophic factor neurturin in patients with α-synucleinopathies

Substantial interest persists for developing neurotrophic factors to treat neurodegenerative diseases. At the same time, significant progress has been made in implementing gene therapy as a means to provide long-term expression of bioactive neurotrophic factors to targeted sites in the brain. Nonetheless, to date, no double-blind clinical trial has achieved positive results on its primary endpoint despite robust benefits achieved in animal models. A major issue with advancing the field is the paucity of information regarding the expression and effects of neurotrophic factors in human neurodegenerative brain, relative to the well-characterized responses in animal models. To help fill this information void, we examined post-mortem brain tissue from four patients with nigrostriatal degeneration who had participated in clinical trials testing gene delivery of neurturin to the putamen of patients. Each had died of unrelated causes ranging from 1.5-to-3-months (2 Parkinson's disease patients), to 4+-years (1 Parkinson's disease and 1 multiple-system atrophy-parkinsonian type patient) following gene therapy. Quantitative and immunohistochemical evaluation of neurturin, alpha-synuclein, tyrosine hydroxylase (TH) and an oligodendroglia marker (Olig 2) were performed in each brain. Comparable volumes-of-expression of neurturin were seen in the putamen in all cases (~15-22%; mean=18.5%). TH-signal in the putamen was extremely sparse in the shorter-term cases. A 6-fold increase was seen in longer-term cases, but was far less than achieved in animal models of nigrostriatal degeneration with similar or even far less NRTN exposure. Less than 1% of substantia nigra (SN) neurons stained for neurturin in the shorter-term cases. A 15-fold increase was seen in the longer-term cases, but neurturin was still only detected in ~5% of nigral cells. These data provide unique insight into the functional status of advanced, chronic nigrostriatal degeneration in human brain and the response of these neurons to neurotrophic factor stimulation. They demonstrate mild but persistent expression of gene-mediated neurturin over 4-years, with an apparent, time-related amplification of its transport and biological effects, albeit quite weak, and provide unique information to help plan and design future trials.

A Technique to Study Meloidogyne arenaria Resistance in Agrobacterium rhizogenes-Transformed Peanut

A reliable peanut root transformation system would be useful to study the functions of genes involved in root biology and disease resistance. The objective of this study was to establish an effective protocol to produce composite plants mediated by Agrobacterium rhizogenes transformation. In total, 75% of transformed peanut seedlings produced an average of 2.83 transgenic roots per plant. Peanut seed had the highest germination rate after treatment in a chlorine gas chamber for 8 h compared with 16 h in chlorine gas or Clorox and mercuric chloride immersion treatments. High transformation efficiency was achieved when the wound site for A. rhizogenes inoculation was covered with vermiculite instead of enclosing the whole plant in a high humidity chamber. On average, 2.5 galls from Meloidogyne arenaria infection were formed per transgenic root from susceptible genotype TifGP-2. These data indicate that A. rhizogenes-transformed roots can be used to phenotype the host response to nematode challenge. Transformation of RLP-2, a candidate resistance gene for M. arenaria integrated into a silencing construct, did not alter the resistance response of Tifguard, even though downregulation of endogenous RLP-2 expression was detected in transformed roots. It is likely that RLP-2 is not the gene conditioning M. arenaria resistance in peanut.

Chemerin suppresses murine allergic asthma by inhibiting CCL2 production and subsequent airway recruitment of inflammatory dendritic cells

BACKGROUND

Chemerin has been implicated to play opposing roles, either pro-inflammatory or anti-inflammatory, in various tissue inflammation processes primarily through the regulation of tissue recruitment of immune cells. However, the effect of chemerin in allergic asthma has not yet been explored. We sought to investigate the role of chemerin in the murine model of allergic asthma and explore the underlying mechanism.

METHODS

We examined the effect of intranasal (i.n.) administration of chemerin during antigen challenge in murine models of asthma. Moreover, we examined whether administration of CCL2 or bone marrow-derived dendritic cells (BMDCs) transfer reversed the effects of chemerin on ovalbumin-induced asthma. We finally examined the effect of chemerin on CCL2 expression in activated lung epithelial cells in vitro.

RESULTS

The administration of chemerin attenuated allergic airway inflammation and airway hyperreactivity during antigen challenge. Chemerin treatment caused significant decreases in BALF CD4(+) T-cell accumulation and mRNA expression of Th2-attracting chemokines, CCL17 and CCL22, which was accompanied by significantly decreased BALF CD11c(+) CD11b(+) inflammatory DC accumulation and CCL2 production. Furthermore, airway administration of exogenous CCL2 or adoptive transfer of CD11c(+) CD11b(+) BMDCs abrogated the suppressive effects of chemerin on allergic asthma. Finally, in vitro study showed that chemerin inhibited CCL2 secretion by low-dose LPS-stimulated lung epithelial cells, which led to decreased chemotaxis of BMDCs.

CONCLUSIONS

Our study demonstrates that chemerin plays a protective role in allergic asthma by suppressing airway recruitment of inflammatory CD11c(+) CD11b(+) DCs through the inhibition of CCL2 secretion by active lung epithelial cells.

Modulation of neutrophil development and homeostasis

Neutrophils are highly motile phagocytic cells that constitute the first line of defense of the innate immune system. Unlike the other innate immune cells, mature neutrophils fully equipped with an armory of granules are short lived cells which are differentiated and programmed from hematopoietic stem cells in the bone marrow. In blood, mature or nearly mature cells are devoid of proliferative potential. While the killing mechanisms of neutrophils have been the research focus in the past, attention was then directed toward granulocytopoiesis by the recent studies about the specific functional states and exact regulatory mechanisms in neutrophil development and homeostasis. Here, we focus on the recent findings regarding the mechanisms that control the generation and homeostasis of neutrophils.

Relative influence of heritability, environment and genetics on serum sclerostin

SUMMARY

We determined factors associated with serum sclerostin in 446 Afro-Caribbean family members. Age, weight, sex, diabetes and kidney function were associated with sclerostin. Sclerostin was heritable, and nine SNPs in the SOST gene region were associated with sclerostin. Variation in serum sclerostin is a heritable factor that is determined by both genetic and environmental factors.

INTRODUCTION

Sclerostin, encoded by the SOST gene, is a Wnt inhibitor that regulates bone mineralization and is a candidate gene locus for osteoporosis. However, little is known about the genetic and non-genetic sources of inter-individual variation in serum sclerostin levels.

METHODS

Serum sclerostin was measured in 446 Afro-Caribbean men and women aged 18+ from seven large, multigenerational families (mean family size, 64; 3,840 relative pairs). Thirty-six common single nucleotide polymorphisms (SNP) were genotyped within a 100 kb region encompassing the gene encoding sclerostin (SOST). Genetic and non-genetic factors were tested for association with serum sclerostin.

RESULTS

Mean serum sclerostin was 41.3 pmol/l and was greater in men than in women (P < 0.05). Factors associated with higher serum sclerostin were increased age and body weight, male sex, diabetes and decreased glomerular filtration rate, which collectively accounted for 25.4 % of its variation. Residual genetic heritability of serum sclerostin was 0.393 (P < 0.0001). Nine SNPs reached nominal significance with sclerostin. Three of those nine SNPs represented independent association signals (rs851056, rs41455049 and rs9909172), which accounted for 7.8 % of the phenotypic variation in sclerostin, although none of these SNPs surpassed a Bonferroni correction for multiple comparisons.

CONCLUSIONS

Serum sclerostin is a heritable trait that is also determined by environmental factors including age, sex, adiposity, diabetes and kidney function. Three independent common SNPs within the SOST region may collectively account for a significant proportion of the variation in serum sclerostin.

Coherent optical transitions in implanted nitrogen vacancy centers

We report the observation of stable optical transitions in nitrogen-vacancy (NV) centers created by ion implantation. Using a combination of high temperature annealing and subsequent surface treatment, we reproducibly create NV centers with zero-phonon lines (ZPL) exhibiting spectral diffusion that is close to the lifetime-limited optical line width. The residual spectral diffusion is further reduced by using resonant optical pumping to maintain the NV(-) charge state. This approach allows for placement of NV centers with excellent optical coherence in a well-defined device layer, which is a crucial step in the development of diamond-based devices for quantum optics, nanophotonics, and quantum information science.

PA28gamma emerges as a novel functional target of tumour suppressor microRNA-7 in non-small-cell lung cancer

BACKGROUND

MicroRNA-7 (miR-7) has been reported to be a tumour suppressor gene. However, whether it has a role in the growth of non-small-cell lung cancer (NSCLC) and what is its target involved in the tumour growth is still under investigation.

METHODS

NSCLC tissue sample, NSCLC cell lines and tissue microarray were investigated in this study. Total RNA, miRNA and protein were used for RT-PCR and western blot analysis. Immunohistochemistry was performed in tissues microarray. Cell culture and intervention experiments were performed in vitro and in vivo. Bioinformatics prediction, western blot and luciferase assay were identified the target of miR-7.

RESULTS

In this study, we found that the expression of miR-7 was significantly downregulated not only in NSCLC cell lines, but also in human NSCLC tissues compared with the matched adjacent tissues. Restoration of its expression through miR-7 mimics in A549 and H1299 NSCLC cells inhibited cell proliferation, colony formation, and cell-cycle progression in vitro. More importantly, the tumorigenicity in nude mice was reduced after administration of miR-7 in vivo. In advance, through bioinformatic analysis, luciferase assay and western blot, we identified a novel target of miR-7, PA28gamma (a proteasome activator) to be enrolled in the regulation with tumour. PA28gamma mRNA and protein levels are markedly upregulated in NSCLC cell lines and tumour samples, exhibiting a strong inverse relation with that of miR-7. In addition, knockdown of PA28gamma induced similar effects as overexpression of miR-7 in NSCLC cells. Furthermore, miR-7 overexpression or silencing of PA28gamma reduced the cyclinD1 expression at mRNA and protein level in NSCLC cell lines.

CONCLUSION

All these findings strongly imply that the overexpression of PA28gamma resulted from miR-7 downexpression in NSCLC has an important role in promoting cancer cell progress and consequently results in NSCLC growth. Thus, strategies targeting PA28gamma and/or miR-7 may become promising molecular therapies in NSCLC treatment.

Epitope specificity of cross-clade neutralizing sera from Chinese HIV-1-positive individuals

Induction of broadly neutralizing antibody is considered important for an effective HIV-1 vaccine. Identification and characterization of broadly neutralizing antibodies in HIV-1-infected patients will facilitate our understanding of the immune correlates to protection and the design of an effective prophylactic vaccine. A number of studies to probe the specificity of antibodies in broadly neutralizing sera in the United States and Europe have been reported. However, little is known about and would be interesting to investigate the immunological characteristics of HIV-1-positive sera in China where non-clade B viruses are prevalent and the circulating viral subtypes are distinct and more complex than both the United States and Europe. Here, we screened 80 Chinese HIV-1-positive sera against a minipanel of pseudoviruses representing various circulating HIV-1 subtypes in China and identified 8 cross-clade neutralizing sera (CNsera). Immunological characterization of the sera showed that gp120-targeting antibodies with multiple epitope specificities contributed to the cross-clade neutralizing activity of these CNsera. V3-directed antibodies were prevalent in these CNsera, but did not mainly contribute to their neutralization breath and potency while CD4bs-specific, 2F5- and 4E10-like antibodies were rarely detected. 2G12-like neutralizing antibodies were more frequently detected in HIV-1 patients from China where recombinant subtype viruses are prevalent than in United States and Europe. One broadly neutralizing serum (Serum 45) was identified to contain antibodies with unknown epitope specificities that were sensitive to terminal glycan modifications on virus Env and insensitive to N160K mutagenesis, and correlated with the cross-clade neutralization activity of Serum 45.

Genetic analysis of mate discrimination in Drosophila simulans

Courtship is an elaborate behavior that conveys information about the identity of animal species and suitability of individual males as mates. In Drosophila, there is extensive evidence that females are capable of evaluating and comparing male courtships, and accepting or rejecting males as mates. These relatively simple responses minimize random sexual encounters involving subpar conspecific males and heterospecific males, and over generations can potentially select novel physical and behavioral traits. Despite its evolutionary and behavioral significance, little is still known about the genes involved in mating choice and how choices for novel males and females arise during evolution. Drosophila simulans and Drosophila sechellia are two recently diverged species of Drosophila in which females have a preference for conspecific males. Here we analyzed a total of 1748 F2 hybrid females between these two species and found a small number of dominant genes controlling the preference for D. simulans males. We also mapped two redundant X-linked loci of mating choice, Macho-XA and Macho-XB, and show that neither one is required for female attractiveness. Together, our results reveal part of the genetic architecture that allows D. simulans females to recognize, mate, and successfully generate progenies with D. simulans males.