A binary pulsar in a 53-minute orbit

Spider pulsars are neutron stars that have a companion star in a close orbit. The companion star sheds material to the neutron star, spinning it up to millisecond rotation periods, while the orbit shortens to hours. The companion is eventually ablated and destroyed by the pulsar wind and radiation1,2. Spider pulsars are key for studying the evolutionary link between accreting X-ray pulsars and isolated millisecond pulsars, pulsar irradiation effects and the birth of massive neutron stars3-6. Black widow pulsars in extremely compact orbits (as short as 62 minutes7) have companions with masses much smaller than 0.1 M⊙. They may have evolved from redback pulsars with companion masses of about 0.1-0.4 M⊙ and orbital periods of less than 1 day8. If this is true, then there should be a population of millisecond pulsars with moderate-mass companions and very short orbital periods9, but, hitherto, no such system was known. Here we report radio observations of the binary millisecond pulsar PSR J1953+1844 (M71E) that show it to have an orbital period of 53.3 minutes and a companion with a mass of around 0.07 M⊙. It is a faint X-ray source and located 2.5 arcminutes from the centre of the globular cluster M71.

[The expression and function of PD-L1 in CD133(+) human liver cancer stem-like cells]

Objective: To investigate the expression of programmed death protein-ligand 1 (PD-L1) in liver cancer stem-like cells (LCSLC) and its effect on the characteristics of tumor stem cells and tumor biological function, to explore the upstream signaling pathway regulating PD-L1 expression in LCSLC and the downstream molecular mechanism of PD-L1 regulating stem cell characteristics, also tumor biological functions. Methods: HepG2 was cultured by sphere-formating method to obtain LCSLC. The expressions of CD133 and other stemness markers were detected by flow cytometry, western blot and real-time quantitative polymerase chain reaction (RT-qPCR) were used to detect the expressions of stemness markers and PD-L1. The biological functions of the LCSLC were tested by cell function assays, to confirm that the LCSLC has the characteristics of tumor stem cells. LCSLC was treated with cell signaling pathway inhibitors to identify relevant upstream signaling pathways mediating PD-L1 expression changes. The expression of PD-L1 in LCSLC was down regulated by small interfering RNA (siRNA), the expression of stem cell markers, tumor biological functions of LCSLC, and the changes of cell signaling pathways were detected. Results: Compared with HepG2 cells, the expression rate of CD133 in LCSLC was upregulated [(92.78±6.91)% and (1.40±1.77)%, P<0.001], the expressions of CD133, Nanog, Oct4A and Snail in LCSLC were also higher than those in HepG2 cells (P<0.05), the number of sphere-formating cells increased on day 7 [(395.30±54.05) and (124.70±19.30), P=0.001], cell migration rate increased [(35.41±6.78)% and (10.89±4.34)%, P=0.006], the number of transmembrane cells increased [(75.77±10.85) and (20.00±7.94), P=0.002], the number of cloned cells increased [(120.00±29.51) and (62.67±16.77), P=0.043]. Cell cycle experiments showed that LCSLC had significantly more cells in the G(0)/G(1) phase than those in HepG2 [(54.89±3.27) and (32.36±1.50), P<0.001]. The tumor formation experiment of mice showed that the weight of transplanted tumor in LCSLC group was (1.32±0.17)g, the volume is (1 779.0±200.2) mm(3), were higher than those of HepG2 cell [(0.31±0.06)g and (645.6±154.9)mm(3), P<0.001]. The expression level of PD-L1 protein in LCSLC was 1.88±0.52 and mRNA expression level was 2.53±0.62, both of which were higher than those of HepG2 cells (P<0.05). The expression levels of phosphorylation signal transduction and transcription activation factor 3 (p-STAT3) and p-Akt in LCSLC were higher than those in HepG2 cells (P<0.05). After the expression of p-STAT3 and p-Akt was down-regulated by inhibitor treatment, the expression of PD-L1 was also down-regulated (P<0.05). In contrast, the expression level of phosphorylated extracellular signal-regulated protein kinase 1/2 (p-ERK1/2) in LCSLC was lower than that in HepG2 cells (P<0.01), there was no significant change in PD-L1 expression after down-regulated by inhibitor treatment (P>0.05). After the expression of PD-L1 was knockdown by siRNA, the expressions of CD133, Nanog, Oct4A and Snail in LCSLC were decreased compared with those of siRNA-negative control (NC) group (P<0.05). The number of sphere-formating cells decreased [(45.33±12.01) and (282.00±29.21), P<0.001], the cell migration rate was lower than that in siRNA-NC group [(20.86±2.74)% and (46.73±15.43)%, P=0.046], the number of transmembrane cells decreased [(39.67±1.53) and (102.70±11.59), P=0.001], the number of cloned cells decreased [(57.67±14.57) and (120.70±15.04), P=0.007], the number of cells in G(0)/G(1) phase decreased [(37.68±2.51) and (57.27±0.92), P<0.001], the number of cells in S phase was more than that in siRNA-NC group [(30.78±0.52) and (15.52±0.83), P<0.001]. Tumor formation in mice showed that the tumor weight of shRNA-PD-L1 group was (0.47±0.12)g, the volume is (761.3±221.4)mm(3), were lower than those of shRNA-NC group [(1.57±0.45)g and (1 829.0±218.3)mm(3), P<0.001]. Meanwhile, the expression levels of p-STAT3 and p-Akt in siRNA-PD-L1 group were decreased (P<0.05), while the expression levels of p-ERK1/2 and β-catenin did not change significantly (P>0.05). Conclusion: Elevated PD-L1 expression in CD133(+) LCSLC is crucial to maintain stemness and promotes the tumor biological function of LCSLC.

No pulsed radio emission during a bursting phase of a Galactic magnetar

Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances^1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources^4-13, but no convincing evidence has been collected so far¹⁴. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts¹⁵. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare^18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.

[Expression of FATS in non-small cell lung cancer and its relationship with prognosis]

Objective: To investigate the expression of fragile-site associated tumor suppressor (FATS) in non-small cell lung cancer and its relationship with clinicopathological features and prognosis. Methods: A total of 140 non-small cell lung cancer (NSCLC) cases and 30 adjacent normal tissues were used to detect the expression level of FATS protein, and to analyze the relationship of FATS protein expression and clinicopathological features and prognosis of NSCLC. Results: Western blot showed that the expression of FATS in adjacent normal tissues was significantly higher than that in non-small cell lung cancer tissues. The results of immunohistochemistry showed that the high expression rate of FATS in 140 cases of NSCLC was 40.0%, and the high expression rate of FATS in 30 cases of adjacent tissues was 73.3%. The difference was statistically significant (P=0.01). Further analysis showed that the TNM stage (P=0.044) and lymph node metastasis (P=0.022) were significant difference between FATS high expression group and low expression group. The 6-year overall survival (OS) rates of NSCLC patients with FATS high-expression and low-expression were 57.1% and 23.8%, respectively, and the 6-year disease-free survival (DFS) rates were 53.6% and 21.4%, respectively, with statistically significant differences (P=0.001). In Cox multivariate analysis, we found gender (HR=1.658, P=0.028; HR=1.684, P=0.023), TNM staging (HR=2.327, P=0.019; HR=2.332, P=0.013) and FATS expression (HR=0.532, P=0.010; HR=0.538, P=0.009) were independent prognostic factors for both OS and DFS of NSCLC patients. Conclusions: The expression of FATS protein is associated with the development and is an independent prognostic factor of NSCLC patients. The detection of FATS protein is expected to be a new biomarker for evaluating the prognosis of NSCLC patients.

Circulation of human metapneumovirus among children with influenza-like illness in Wuhan, China

Human metapneumovirus (HMPV) is a worldwide distributed pathogen of the respiratory tract. The objectives of this study were to identify HMPV infections among children with influenza‐like illness (ILI) in Wuhan and to assess circulation patterns and molecular diversity of HMPV in this area. From July 2008 to December 2013, a total of 3,883 throat swab samples were collected from ILI outpatients under 16 years old. HMPV RNA was detected in 171 samples (4.40%). All the four subtypes of HMPV were identified, among which A2 was the most common subtype (61/145, 42.1%), followed by B1, B2, and A1. During the study period, HMPV circulation presented a biennial alternation between high and low incidence in Wuhan and the seasonal peak also shift between winter and spring in two continuous seasons. Subtype A2, B1, and B2 co‐circulated during the study period, with genotype A prevailing in epidemic season 2008–2009 and 2012–2013, and genotype B prevailing during other periods. This large‐scale analysis of HMPV prevalence in ILI outpatient children improves the understanding of local HMPV circulation patterns and provides molecular epidemic evidence for comparative analysis of HMPV infection. J. Med. Virol. 88:774–781, 2016. © 2015 Wiley Periodicals, Inc.

Time series analysis of reported cases of hand, foot, and mouth disease from 2010 to 2013 in Wuhan, China

Background

Hand, foot, and mouth disease (HFMD) is an infectious disease caused by a group of enteroviruses, including Coxsackievirus A16 (CVA16) and Enterovirus A71 (EV-A71). In recent decades, Asian countries have experienced frequent and widespread HFMD outbreaks, with deaths predominantly among children. In several Asian countries, epidemics usually peak in the late spring/early summer, with a second small peak in late autumn/early winter. We investigated the possible underlying association between the seasonality of HFMD epidemics and meteorological variables, which could improve our ability to predict HFMD epidemics.

Methods

We used a time series analysis composed of a spectral analysis based on the maximum entropy method (MEM) in the frequency domain and the nonlinear least squares method in the time domain. The time series analysis was applied to three kinds of monthly time series data collected in Wuhan, China, where high-quality surveillance data for HFMD have been collected: (i) reported cases of HFMD, (ii) reported cases of EV-A71 and CVA16 detected in HFMD patients, and (iii) meteorological variables.

Results

In the power spectral densities for HFMD and EV-A71, the dominant spectral lines were observed at frequency positions corresponding to 1-year and 6-month cycles. The optimum least squares fitting (LSF) curves calculated for the 1-year and 6-month cycles reproduced the bimodal cycles that were clearly observed in the HFMD and EV-A71 data. The peak months on the LSF curves for the HFMD data were consistent with those for the EV-A71 data. The risk of infection was relatively high at 10 °C ≤ t < 15 °C (t, temperature [°C]) and 15 °C ≤ t < 20 °C, and peaked at 20 °C ≤ t < 25 °C.

Conclusion

In this study, the HFMD infections occurring in Wuhan showed two seasonal peaks, in summer (June) and winter (November or December). The results obtained with a time series analysis suggest that the bimodal seasonal peaks in HFMD epidemics are attributable to EV-A71 epidemics. Our results suggest that controlling the spread of EV-A71 infections when the temperature is approximately 20–25 °C should be considered to prevent HFMD infections in Wuhan, China.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-1233-0) contains supplementary material, which is available to authorized users.

A Comparison of the Number of Men Who Have Sex with Men among Rural-To-Urban Migrants with Non-Migrant Rural and Urban Residents in Wuhan, China: A GIS/GPS-Assisted Random Sample Survey Study

Background

Mobile populations and men who have sex with men (MSM) play an increasing role in the current HIV epidemic in China and across the globe. While considerable research has addressed both of these at-risk populations, more effective HIV control requires accurate data on the number of MSM at the population level, particularly MSM among migrant populations.

Methods

Survey data from a random sample of male rural-to-urban migrants (aged 18-45, n=572) in Wuhan, China were analyzed and compared with those of randomly selected non-migrant urban (n=566) and rural counterparts (580). The GIS/GPS technologies were used for sampling and the survey estimation method was used for data analysis.

Results

HIV-related risk behaviors among rural-to-urban migrants were similar to those among the two comparison groups. The estimated proportion of MSM among migrants [95% CI] was 5.8% [4.7, 6.8], higher than 2.8% [1.2, 4.5] for rural residents and 1.0% [0.0, 2.4] for urban residents, respectively. Among these migrants, the MSM were more likely than non-MSM to be older in age, married, and migrated to more cities. They were also more likely to co-habit with others in rental properties located in new town and neighborhoods with fewer old acquaintances and more entertainment establishments. In addition, they were more likely to engage in commercial sex and less likely to consistently use condoms.

Conclusion

Findings of this study indicate that compared to rural and urban populations, the migrant population in Wuhan consists of a higher proportion of MSM who also exhibit higher levels of HIV-related risk behaviors. More effective interventions should target this population with a focus on neighborhood factors, social capital and collective efficacy for risk reduction.

Heroin use promotes HCV infection and dysregulates HCV-related circulating microRNAs

Hepatitis C virus (HCV) infection is common among injection drug users (IDUs). There is accumulating evidence that circulating microRNAs (miRNAs) are associated with HCV infection and disease progression. The present study was undertaken to determine the in vivo impact of heroin use on HCV infection and HCV-related circulating miRNA expression. Using the blood specimens from four groups of the study subjects (HCV-infected individuals, heroin users with/without HCV infection, and healthy volunteers), we found that HCV-infected heroin users had significantly higher viral load than HCV-infected non-heroin users (p = 0.0004). Measurement of HCV-related circulating miRNAs in plasma showed that miRs-122, 141, 29a, 29b, and 29c were significantly increased in the heroin users with HCV infection, whereas miR-351, an HCV inhibitory miRNA, was significantly decreased in heroin users as compared to control subjects. Further investigation identified a negative correlation between the plasma levels of miR-29 family members and severity of HCV infection based on aspartate aminotransferase to platelet ratio index (APRI). In addition, heroin use and/or HCV infection also dysregulated a panel of plasma miRNAs. Taken together, these data for the first time revealed in vivo evidence that heroin use and/or HCV infection alter circulating miRNAs, which provides a novel mechanism for the impaired innate anti-HCV immunity among IDUs.

Molecular characterization of the complete genome of a street rabies virus WH11 isolated from donkey in China

The complete genomic sequence of a rabies virus isolate WH11, isolated from brain tissue of a rabid donkey in China, was determined and compared with other rabies viruses. This is the first Chinese street strain which was isolated from donkey and the entire length and organization of the virus was similar to that of other rabies viruses. Multiple alignments of amino acid sequences of the nucleoprotein, phosphoprotein, matrix protein, glycoprotein, and large protein of WH11 with those of other rabies viruses were undertaken to examine the conservative degree of functional regions. Phylogenetic analysis using the complete genomic sequence of WH11 determined that this isolate is most closely related with rabies viruses previously isolated in China and the attenuated Chinese vaccine strain CTN181.

Anti‐smoking practice in hospitals

Purpose

This study aims to examine whether, in the opinion of patients selected in 13 hospitals of Hubei province, China, hospitals are smoke free. Patients were also asked whether their physicians had inquired about their smoking status.

Design/methodology/approach

Patients were recruited through an intercept method (i.e. stopped by the interviewer while in the hospital); data were collected through interviews, with a response rate of 96.1 percent.

Findings

Among the intercepted patients, 48.3 percent reported having seen people smoking in hospitals; 22.3 percent had seen a doctor and/or nurse smoking; 23.8 percent had smelled tobacco in hospitals; 68.4 percent reported having seen “no‐smoking” signs in hospital settings; 42.6 percent reported having been asked about smoking status in their latest visit to a doctor and 23.8 percent reported receiving tobacco cessation counseling. Compared to hospitals in large cities, patients from medium/small city hospitals reported significantly higher levels of cigarette smoking among physicians, and poorer implementation of regulations for a smoking‐free hospital, and less smoking cessation counseling by physicians.

Originality/value

Findings of this study point to the need for greater efforts to be made in promoting a smoke free environment in hospitals, as well as encouraging physicians to provide more smoking cessation counseling to smoking patients, particularly physicians in small and medium hospitals.

The epidemiology and etiology of influenza-like illness in Chinese children from 2008 to 2010

Influenza-like illness can be caused by a wide range of respiratory viruses. In order to investigate the epidemiology of viral pathogens related to influenza-like illness in children of Wuhan, the largest city in central China, throat swab samples were collected from 1,472 young patients, from July 2008 to June 2010, before and after the occurrence of the 2009 pandemic influenza A (H1N1) virus (pH1N1). It was found that 923 patients (62.7%) were positive for at least 1 virus and 90 patients (9.8%) were detected for multiple (≥2) respiratory viruses by real-time PCR detection of 16 viruses. Seasonal influenza A virus was the predominant pathogen among all the 16 viruses with a positive rate of 13.3% (196/1,472), which was followed by pH1N1 (159/1,472). It was also noted that the viral distribution pattern in Wuhan changed upon the introduction of the pH1N1 virus.

[Identification and sequential analysis on rabies virus isolated from a donkey]

OBJECTIVE

To identify and analyze the genetic characteristics of nucleoprotein (N) and glycoprotein (G) genes of rabies virus (RABV) isolated from a donkey in Wuhan. N gene and G gene of the virus were compared with other representative street strains isolated around Hubei areas as well as the vaccine strains used in China and abroad.

METHODS

RABV in brain tissue of a donkey was detected by direct immunofluorescent method and then inoculated in suckling mice to observe the incidence of rabies. Brain samples of the donkey and infected suckling mice were detected by ELISA. The N gene and G gene fragment of the isolated RABV were amplified by RT-PCR and cloned into pMD18-T vector for sequencing and genetic analysis.

RESULTS

RABVs were detected in both donkey brain and suckling mice brain samples. The N gene and G gene nucleotide homology of RABV isolated from the donkey with other representative street strains found around Hubei areas as well as vaccine strains used in China and abroad were 85.7% - 99.1% and 82.2% - 99.7%, and the deduced amino acid identity were 95.6% - 99.8% and 87.8% - 99.4%, respectively.

CONCLUSION

Novel RABV was successfully identified and isolated from a donkey and showed close relationship to the representative street strains found around Hubei areas as well as vaccine strains used in China through genetic analysis.

[Identification of Haemaphysalis longicornis and Rhipicephalus microplus]

OBJECTIVE

To establish a method combined morphology and molecular marker for identifying Haemaphysalis longicornis and Rhipicephalus microplus.

METHODS

Ticks were collected from domestic animals and wild environment in epidemic area of Hubei and Henan provinces where cases of fever with thrombocytopenia syndrome were prevalent. We classified the ticks by morphology characteristics before 12S rDNA of ticks were amplified by PCR and subsequently sequenced. Phylogenetic tree was constructed by PAUP4.0.

RESULTS

The ticks belonged to Haemaphysalis longicornis and Rhipicephalus microplus through observation and analysed by the morphological characteristics of the ticks. 12S rDNA was cloned and sequenced while data confirmed the morphological identification of the results.

CONCLUSION

The method based on morphology that combined with molecular marker seemed a good method for the identification of ticks.

Change of BMD after weaning or resumption of menstruation in Chinese women with different FokI VDR-genotypes: a randomized, placebo-controlled, calcium supplementation trial

OBJECTIVE

To investigate the effect of calcium supplementation on bone mineral density (BMD) in Chinese women with different FokI vitamin D receptor (VDR) genotypes (FF, Ff, and ff) after weaning or resumption of menstruation during lactation.

METHODS

A total of 40 subjects with the same FokI VDR genotype were randomly divided into two groups: one received calcium tablet (600 mg once daily as CaCO(3)) and the other placebo tablet once daily for 1 year. At baseline, BMD was measured by dual-energy X-ray absorptiometry at lumbar spine (L2-L4) and at left hip whereas serum PICP, serum OC, and urinary CTX, serum 25(OH)VitD(3), and serum estradiol were measured at weaning and 1 year thereafter.

RESULTS

After the intervention, BMD at lumbar spine and at left hip increased significantly in all these women with a trend among different FokI VDR genotypes such as FF > Ff > ff (P<0.05, <0.01, and <0.001, respectively). BMD at lumbar spine in women with FF VDR genotype increased much more rapidly than in those with ff VDR genotype (P<0.05). Compared with the control group women with the FF genotype regained more BMD after calcium supplementation (P<0.05).

CONCLUSION

Daily calcium 600 mg supplementation has beneficial effect on the bone health of women with FF VDR genotype.

[Effect of calcium supplementation on the regain of BMD in Chinese lactating women with 4 major combined ER genotypes]

OBJECTIVE

To observe the regain of bone mineral density (BMD) in Chinese lactating women with 4 major combined ER genotypes (defined as Pvu II and Xba I).

METHODS

A total of 160 healthy lactating women was selected, 40 women with each of 4 genotypes (ppxx, Ppxx, PpXX or PPXx) were divided into a calcium supplement group received 600 mg calcium (as CaCO3) daily, and a control group. BMD of lumbar spine and left hip were measured by dual energy X-ray absorption bone densitometry on 3 months and one year after delivery. Calcium intake was calculated from a 3 days dietary recall.

RESULTS

Whether supplementing calcium or not, the BMD of these women increased obviously (P <0.05).The less BMD regaining at hip was observed in women with ppxx genotype than those with Ppxx or PPXx genotype (P <0.05) when 600 mg calcium was given daily. Calcium supplementation and the duration of lactation were significantly related to hip BMD via a stepwise linear regression analysis (the standardized coefficient was 0.227, and P value was 0. 007).

CONCLUSION

Although the dietary calcium intake was low in Wuhan lactating women, the BMD of lumbar spine or of left hip of women with some genotypes was increased greatly by calcium supplementation.

Part 2. Association of daily mortality with ambient air pollution, and effect modification by extremely high temperature in Wuhan, China

Fewer studies have been published on the association between daily mortality and ambient air pollution in Asia than in the United States and Europe. This study was undertaken in Wuhan, China, to investigate the acute effects of air pollution on mortality with an emphasis on particulate matter (PM*). There were three primary aims: (1) to examine the associations of daily mortality due to all natural causes and daily cause-specific mortality (cardiovascular [CVD], stroke, cardiac [CARD], respiratory [RD], cardiopulmonary [CP], and non-cardiopulmonary [non-CP] causes) with daily mean concentrations (microg/m3) of PM with an aerodynamic diameter--10 pm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), or ozone (O3); (2) to investigate the effect modification of extremely high temperature on the association between air pollution and daily mortality due to all natural causes and daily cause-specific mortality; and (3) to assess the uncertainty of effect estimates caused by the change in International Classification of Disease (ICD) coding of mortality data from Revision 9 (ICD-9) to Revision 10 (ICD-10) code. Wuhan is called an "oven city" in China because of its extremely hot summers (the average daily temperature in July is 37.2 degrees C and maximum daily temperature often exceeds 40 degrees C). Approximately 4.5 million residents live in the core city area of 201 km2, where air pollution levels are higher and ranges are wider than the levels in most cities studied in the published literature. We obtained daily mean levels of PM10, SO2, and NO2 concentrations from five fixed-site air monitoring stations operated by the Wuhan Environmental Monitoring Center (WEMC). O3 data were obtained from two stations, and 8-hour averages, from 10:00 to 18:00, were used. Daily mortality data were obtained from the Wuhan Centres for Disease Prevention and Control (WCDC) during the study period of July 1, 2000, to June 30, 2004. To achieve the first aim, we used a regression of the logarithm of daily counts of mortality due to all natural causes and cause-specific mortality on the daily mean concentrations of the four pollutants while controlling for weather, temporal factors, and other important covariates with generalized additive models (GAMs). We derived pollutant effect estimations for 0-day, 1-day, 2-day, 3-day, and 4-day lagged exposure levels, and the averages of 0-day and 1-day lags (lag 0-1 day) and of 0-day, 1-day, 2-day, and 3-day lags (lag 0-3 days) before the event of death. In addition, we used individual-level data (e.g., age and sex) to classify subgroups in stratified analyses. Furthermore, we explored the nonlinear shapes ("thresholds") of the exposure-response relations. To achieve the second aim, we tested the hypothesis that extremely high temperature modifies the associations between air pollution and daily mortality. We developed three corresponding weather indicators: "extremely hot," "extremely cold," and "normal temperatures." The estimates were obtained from the models for the main effects and for the pollutant-temperature interaction for each pollutant and each cause of mortality. To achieve the third aim, we conducted an additional analysis. We examined the concordance rates and kappa statistics between the ICD-9-coded mortality data and the ICD-10-coded mortality data for the year 2002. We also compared the magnitudes of the estimated effects resulting from the use of the two types of ICD-coded mortality data. In general, the largest pollutant effects were observed at lag 0-1 day. Therefore, for this report, we focused on the results obtained from the lag 0-1 models. We observed consistent associations between PM10 and mortality: every 10-microg/m3 increase in PM10 daily concentration at lag 0-1 day produced a statistically significant association with an increase in mortality due to all natural causes (0.43%; 95% confidence interval [CI], 0.24 to 0.62), CVD (0.57%; 95% CI, 0.31 to 0.84), stroke (0.57%; 95% CI, 0.25 to 0.88), CARD (0.49%; 95% CI, 0.04 to 0.94), RD (0.87%; 95% CI, 0.34 to 1.41), CP (0.52%; 95% CI, 0.27 to 0.77), and non-CP (0.30%; 95% CI, 0.05 to 0.54). In general, these effects were stronger in females than in males and were also stronger among the elderly (> or = 65 years) than among the young. The results of sensitivity testing over the range of exposures from 24.8 to 477.8 microg/m3 also suggest the appropriateness of assuming a linear relation between daily mortality and PM10. Among the gaseous pollutants, we also observed statistically significant associations of mortality with NO, and SO2, and that the estimated effects of these two pollutants were stronger than the PM10 effects. The patterns of NO2 and SO2 associations were similar to those of PM10 in terms of sex, age, and linearity. O3 was not associated with mortality. In the analysis of the effect modification of extremely high temperature on the association between air pollution and daily mortality, only the interaction of PM10 with temperature was statistically significant. Specifically, the interaction terms were statistically significant for mortality due to all natural (P = 0.014), CVD (P = 0.007), and CP (P = 0.014) causes. Across the three temperature groups, the strongest PM10 effects occurred mainly on days with extremely high temperatures for mortality due to all natural (2.20%; 95% CI, 0.74 to 3.68), CVD (3.28%; 95% CI, 1.24 to 5.37), and CP (3.02%; 95% CI, 1.03 to 5.04) causes. The weakest effects occurred at normal temperature days, with the effects on days with low temperatures in the middle. To assess the uncertainty of the effect estimates caused by the change from ICD-9-coded mortality data to ICD-10-coded mortality data, we compared the two sets of data and found high concordance rates (> 99.3%) and kappa statistics close to 1.0 (> 0.98). All effect estimates showed very little change. All statistically significant levels of the estimated effects remained unchanged. In conclusion, the findings for the aims from the current study are consistent with those in most previous studies of air pollution and mortality. The small differences between mortality effects for deaths coded using ICD-9 and ICD-10 show that the change in coding had a minimal impact on our study. Few published papers have reported synergistic effects of extremely high temperatures and air pollution on mortality, and further studies are needed. Establishing causal links between heat, PM10, and mortality will require further toxicologic and cohort studies.

A critical function of toll-like receptor-3 in the induction of anti-human immunodeficiency virus activities in macrophages

Toll-like receptor-3 (TLR-3) recognizes double-stranded RNA and induces multiple intracellular events responsible for innate anti-viral immunity against a number of viral infections. Activation of TLR-3 inhibits human immunodeficiency virus (HIV) replication, but the mechanism(s) underlying the action of TLR-3 activation on HIV are largely unknown. Here we demonstrate that treatment of monocyte-derived macrophages with poly I:C, a synthetic ligand for TLR-3, significantly inhibited HIV infection and replication. Investigation of the mechanisms showed that TLR-3 activation resulted in the induction of type I interferon inducible antiviral factors, including APOBEC3G and tetherin, the newly identified anti-HIV cellular proteins. In addition, poly I:C-treated macrophages expressed increased levels of CC chemokines, the ligands for CCR5. Furthermore, TLR-3 activation in macrophages induced the expression of cellular microRNAs (miRNA-28, -125b, -150, -223 and -382), the newly identified intracellular HIV restriction factors. These findings indicate that TLR-3-mediated induction of multiple anti-HIV factors should be beneficial for the treatment of HIV disease where innate immune responses are compromised by the virus.

Activation of Toll-like receptors inhibits herpes simplex virus-1 infection of human neuronal cells

Toll-like receptors (TLRs) play an essential role in initiating intracellular type I interferon (IFN)-mediated innate immunity against viral infections. We examined whether human neuronal cells (primary human neurons, NT2-N and CHP-212 cells) express TLRs and mount type I IFN-mediated innate immunity against herpes simplex virus-1 (HSV-1) infection. Human neuronal cells expressed TLR family members 1-10 and IFN-alpha/beta. The activation of TLR3 or TLR8 by double-stranded RNA (poly-I:C) or single-stranded RNA (ssRNA) induced IFN-alpha/beta expression. In addition, HSV-1 infection of human neuronal cells induced IFN-alpha expression. Investigation of the mechanisms showed that poly-I:C or ssRNA treatment enhanced the expression of several IFN regulatory factors. Importantly, the activation of TLR3 or TLR8 by poly-I:C or ssRNA prior to HSV-1 infection reduced the susceptibility of the neuronal cells to infection. These observations indicate that human neuronal cells possess intracellular TLR-mediated innate immune protection against HSV-1 infection.

[Transcriptional regulation of the human gene coding for proline-rich nuclear receptor coactivator (pnrc) by regulatory factor x (rfx1)]

PNRC (Proline-rich Nuclear Receptor Coactivator) is a novel coactivator for multiple nuclear receptors. PNRC was previously identified using bovine SF-1 (steroidogenic factor 1) as the bait in a yeast two-hybrid screening of a human mammary gland cDNA expression library. To understand the molecular mechanisms that regulate the expression of human PNRC gene, in this study, functional analysis of the 5' flanking region of the human PNRC gene revealed that the -123/+27 region is the minimal promoter of the human PNRC gene. Gel shift and ChIP analyses demonstrated the specific binding of RFX1 (Regulatory Factor X) protein to the human PNRC promoter region. In co-transfection experiments RFX1 was shown to repress promoter activity of PNRC gene in a dose-dependent manner. These results indicate that r RFX1 specifically bind to promoter region and negatively regulate the transcription of the human PNRC gene.

High temperatures enhanced acute mortality effects of ambient particle pollution in the "oven" city of Wuhan, China

BACKGROUND

We investigated whether the effect of air pollution on daily mortality is enhanced by high temperatures in Wuhan, China, using data from 2001 to 2004. Wuhan has been called an "oven" city because of its hot summers. Approximately 4.5 million permanent residents live in the 201-km(2) core area of the city.

METHOD

We used a generalized additive model to analyze pollution, mortality, and covariate data. The estimates of the interaction between high temperature and air pollution were obtained from the main effects and pollutant-temperature interaction models.

RESULTS

We observed effects of consistently and statistically significant interactions between particulate matter < or = 10 microm (PM(10)) and temperature on daily nonaccidental (p = 0.014), cardiovascular (p = 0.007), and cardiopulmonary (p = 0.014) mortality. The PM(10) effects were strongest on extremely high-temperature days (daily average temperature, 33.1 degrees C), less strong on extremely low-temperature days (2.2 degrees C), and weakest on normal-temperature days (18.0 degrees C). The estimates of the mean percentage of change in daily mortality per 10-mug/m(3) increase in PM(10) concentrations at the average of lags 0 and 1 day during hot temperature were 2.20% (95% confidence interval), 0.74-3.68) for nonaccidental, 3.28% (1.24-5.37) for cardiovascular, 2.35% (-0.03 to 4.78) for stroke, 3.31% (-0.22 to 6.97) for cardiac, 1.15% (-3.54% to 6.07) for respiratory, and 3.02% (1.03-5.04) for cardiopulmonary mortality.

CONCLUSIONS

We found synergistic effects of PM(10) and high temperatures on daily nonaccidental, cardiovascular, and cardiopulmonary mortality in Wuhan.

Perceived stress, depression and food consumption frequency in the college students of China seven cities

The aim of the study was to explore the association between perceived stress, depression and food consumption frequency. A self-administered questionnaire that included the perceived stress scale, the depression scale and dietary intake was used in the baseline survey of a cohort study of 2579 local college students over 7 cities in China. Gender and city differences were found in perceived stress scores and depression scores. There were also significant differences among diverse smoking levels and among perceived weight categories in perceived stress and depression scores. Stepwise logistic regression models found that frequency of consumption of fresh fruit, ready-to-eat food and snack food had apparently independent effects on perceived stress, whereas the intake level of fresh fruit, ready-to-eat food and fast food was significantly associated with depression. The link between food consumption frequency, perceived stress and depression suggests that diet intervention may be considered a mediate strategy integrated in psychology prevention program among normal population of the college.

[The impact of social norm and susceptibility on drug use among adolescents]

OBJECTIVE

To investigate the role of knowledge, attitude and perceived social norm on the use of New Type of Drugs (NTD) and to construct the mediated model among these factors.

METHODS

With stratified random group sampling, 3018 students from 3 middle schools, 3 high schools, 3 vocational high schools and a municipal-own university in Wuhan city completed questionnaires under anonymous and voluntary practice. A conceptual model was developed based on Reasoned Behavior Theory. Structural equation modeling (SEM) was used to test the proposed model.

RESULTS

The overall prevalent rate of NTD was 3.28%, with 4.81% for males, 1.94% for females,1.80% for middle school students, 2.91% for general high school students, 7.83% for vocational school students and 3.25% for college students. SEM seemed to have been fixed nicely into the model. Adolescent NTD was significantly predicted by knowledge, attitude, perceived social norm which were all directly affecting or medicated by the susceptibility of drugs.

CONCLUSION

Knowledge, attitude, perceived social norm might increase the risks for NTD use among adolescents, suggesting that preventive education on drug use among adolescents should be paid to improve the knowledge on drugs.

Tobacco use among youth and adults in Mainland China: the China Seven Cities Study

OBJECTIVE

The China Seven Cities Study (CSCS) monitors geographic and temporal trends in tobacco use among adolescents and adults in seven cities throughout Mainland China: Harbin, Shenyang, Wuhan, Chengdu, Kunming, Hangzhou, and Qingdao. This article presents the methodology and prevalence data from the baseline survey of the CSCS, conducted in 2002.

METHODS

Stratified random samples of middle schools, high schools, and colleges were selected within each city. Students and their parents completed self-report surveys of their tobacco use. Data were obtained from 6138 middle school students, 5848 academic high school students, 2448 vocational high school students, 2556 college students, and 25 697 parents.

RESULTS

Smoking prevalence varied across age groups, school types, genders, and cities. Past-month smoking prevalence was 9% among middle school students, 8% among academic high school students, 26% among vocational high school students, 21% among college students, and 40% among parents. Smoking prevalence was higher among males than among females, with larger gender disparities among adults than among youth. Smoking also varied across cities, with higher smoking prevalence in southwestern cities and lower prevalence in coastal cities. Intraclass correlations of students within schools are presented to inform statistical power estimates for further research in China.

CONCLUSIONS

These results provide a baseline for future longitudinal studies of smoking in these cities and identify demographic groups at risk for tobacco-related disease. Effective smoking prevention programmes for youth and smoking cessation programmes for adults are needed in China, especially in the lower-income southwestern cities and in vocational high schools throughout the country.

[Influenza surveillance and antigenic and genetic characterization of predominant strains in Wuhan area in 2003]

OBJECTIVE

To study influenza epidemic and analyze antigenic and genetic characterization of the predominant strains in Wuhan area in 2003.

METHODS

Epidemiological data and specimens from influenza patients were collected from surveillance sites weekly. Viruses were isolated from the specimens. Three H3 isolates were chosen to do antigenic analysis by hemagglutination inhibition (HI) test and their HA1 region was sequenced.

RESULTS

Totally 58 influenza viruses were isolated from 418 specimens, 57 of them were identified as H3 subtype and 1 of them was B subtype; both monthly positive rate and numbers of influenza like illness had two peaks of winter and summer, the highest peak appeared in July. The 3 new H3 isolates were antigenically different from vaccine strain A/Panama/2007/99, 14 amino acid changes have been found in HA1 domain of these 3 strains compared with A/Panama/2007/99, phylogenetic analysis also confirmed the difference in HA1 domain.

CONCLUSIONS

Influenza epidemic had two peaks in Wuhan area in 2003. The activity of H3 virus was strengthened remarkably. And they are antigenically and genetically different from the vaccine strain.

A site-directed mutagenesis study of human placental aromatase

Aromatase, a cytochrome P-450, catalyzes the formation of aromatic C18 estrogenic steroids from C19 androgens. Using the x-ray structure of cytochrome P-450cam as the model, seven mutants of human aromatase were designed and expressed in Chinese hamster ovary cells by a stable expression method. They are His-128----Gln, His-128----Ala, Cys-299----Ala, Glu-302----Leu, Asp-309----Asn, Asp-309----Ala, and Ser-312----Cys. The presence of the aromatase mutants in the transfected Chinese hamster ovary cells were confirmed by immunoprecipitation analysis. The kinetic parameters of these mutants using [1 beta,2 beta-3H] androstenedione (or [1 beta-3H]androstenedione), and [1 beta,2 beta-3H]testosterone as substrates were determined. In addition, inhibition profiles for these mutants with two aromatase inhibitors, 4-hydroxyandrostenedione and aminoglutethimide were obtained. Furthermore, the reactions catalyzed by these mutants were examined by evaluating the levels of the product estrone, and two intermediates, 19-hydroxyandrostenedione and 19-oxoandrostenedione by reverse phase high performance liquid chromatography using [7-3H]androstenedione as the substrate. Our results indicate that among the positions we modified, Asp-309 appears to be very important for the enzyme catalysis.

[Changes in leucocytic estrogen receptor levels in patients with climacteric syndrome and therapeutic effect of liuwei dihuang pills]

The numbers of estrogen receptor (ER) in human peripheral leucocytes in 22 women with climacteric syndrome were measured by radioligand method. The results were compared with those of 12 normal child-bearing-age women. It wat found that the contents of leucocytic ER in climacteric syndrome patients were significantly lower than normal child-bearing-age women. The authors used a Chinese prescription--Liuwei Dihuang Pills (LDP) to treat the patients for 2 months. The numbers of leucocytic ER were significantly increased after treatment. The data indicate that decrease of ER levels in cell may involve in the pathogenesis of climacteric syndrome. LDP not only increases plasma estradiol levels, but also increases the leucocytic ER levels. This may be the basis of the therapeutic effect on the disease.

[Changes in levels of leucocytic estrogen receptor in patients with menopausal type II diabetes and its significance]

The number of estrogen receptors (ER) in human peripheral leucocytes in 12 women with menopausal type II diabetes was measured with radio-ligand binding method. The results were compared with those of 12 menopausal women without diabetes and 12 normal women of childbearing age. It was found that the number of ER in the patients was significantly decreased. Our data indicate that decrease of ER level in leukocytes may be related to the pathogenesis of type II diabetes in menopausal period.

[Changes in leucocytic estrogen receptor levels in patients with gynecomastia]

The number of estrogen receptor (ER) in human peripheral leucocytes in 13 men with gynecomastia were measured by radioligand binding method. The results were compared with those of 13 sex-and age-matched healthy subjects. It was found that the number of ER in leucocytes was significantly increased in gynecomastia (Rs of leucocytes were 1054 +/- 254 sites/cell). It suggested that increase of ER levels play an important role in the pathogenesis of gynecomastia.

Stable expression of human aromatase complementary DNA in mammalian cells: a useful system for aromatase inhibitor screening

A mammalian cell expression plasmid, pH beta-Aro, containing the human placenta aromatase complementary DNA was constructed. The prepared plasmid was used to transfect breast cancer cells (MCF-7), noncancerous breast cells (HBL-100), and Chinese hamster ovary cells by a stable expression method. While the maximum velocities for aromatase expressed in three types of cells were different (10-201 pmol of [3H2O] formed/h/mg) using [1 beta, 2 beta-3H]androst-4-ene-3,17-dione as the substrate, the apparent Michaelis-Menten constants were found to be similar (39.9-57.8 nM) and were within the range determined for the enzyme existing in human placenta. The expressed activities were inhibited by the known aromatase inhibitors, 4-hydroxyandrostenedione and aminoglutethimide, at concentrations that normally inhibit the human placental aromatase. However, it was found that the inhibition profiles were different for aromatase expressed in different types of cells, suggesting that other factors, such as the uptake of the inhibitor, may also play a role in determining the inhibition efficiency. These constructed aromatase expressing mammalian cell lines will be very useful tools for aromatase inhibitor screening.

Analysis of proto-oncogenes in acute myeloid leukemia: loss of heterozygosity for the Ha-ras gene

At least 13 of 34 patients with acute myeloid leukemia (AML) of varying FAB types were heterozygous for a BamHI restriction fragment length polymorphism (RFLP) of the Ha-ras gene on chromosome 11. In 4 of these 13 patients, one allele of the Ha-ras gene was deleted. Two of these cases had an informative heterozygosity for an RFLP on the long arm of chromosome 11. Analysis of these cases indicated that loss of genes from chromosome 11 was restricted to the short arm. In three cases with loss of one Ha-ras gene, the remaining gene had no mutations in critical areas of exons 1 and 2. With the exception of one AML case with amplification of MYC, no gross structural abnormalities in 12 other oncogenes were detected.

Proto-oncogene abnormalities in human breast cancer: c-ERBB-2 amplification does not correlate with recurrence of disease

The incidence of c-ERBB-2 amplification in breast cancers and its usefulness as a predictor of tumor recurrence after treatment have been subjects of controversy (Ali et al., 1988, Slamon et al., 1987). We re-examined this subject by analysing 157 primary and 14 metastatic breast cancers with c-ERBB-2 and 18 other molecular probes as controls. Five proto-oncogenes were found to be occasionally amplified in primary breast cancers: c-ERBB-2 (11%), c-MYB (3%), c-RAS-Ki (3%), INT-2 (4%) and c-MYC (6%). No statistically significant correlation between amplification of c-ERBB-2 and recurrence of tumors was observed. The only significant correlation observed was between early recurrence of advanced (stage III) tumors and amplification of one or another of the above five proto-oncogenes. We conclude that breast cancer utilize multiple genetic mechanisms in their progression and metastasis, and that analysis of c-ERBB-2 alone is not a useful guide.

A unique pattern of proto-oncogene abnormalities in ovarian adenocarcinomas

Twelve cases of ovarian adenocarcinoma were studied for alterations in proto-oncogenes, and a unique pattern of altered ras proto-oncogenes was observed. Amplification of ras-Ki was found in three of seven ovarian tumors and amplification of ras-Ha in one of 12. In contrast, ras-Ha amplification was not found in any of the 334 other tumors and ras-Ki amplification was only seen in breast cancer at a frequency of 3%. Other proto-oncogenes altered in ovarian adenocarcinomas included c-myc and c-erbb-2. Proto-oncogene abnormalities were more frequent in aggressive tumors of high histologic grade.

Amplification of human int-2 in breast cancers and squamous carcinomas

Murine int-2 is one of the genetic loci implicated in the induction of mouse breast cancers by murine mammary tumor virus. An homologous gene has recently been identified in the human genome (Casey et al., 1986). The human int-2 locus was found to be amplified 7- to 25-fold in 4 of 46 infiltrating ductal breast cancers and 30- to 60-fold in 2 of 8 squamous carcinomas of the head and neck region, but not in other cancers. All of the involved tumors had metastasized to regional lymphatics at the time of analysis and five exhibited clinically aggressive behavior.