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The lockdown due to COVID-19 created a rare opportunity to examine the nonlinear responses of secondary aerosols, which are formed through atmospheric oxidation of gaseous precursors, to intensive precursor emission reductions. Based on unique observational data sets from six supersites in eastern China during 2019-2021, we found that the lockdown caused considerable decreases (32-61%) in different secondary aerosol components in the study region because of similar-degree precursor reductions. However, due to insufficient combustion-related volatile organic compound (VOC) reduction, odd oxygen (Ox = O3 + NO2) concentration, an indicator of the extent of photochemical processing, showed little change and did not promote more decreases in secondary aerosols. We also found that the Chinese provinces and international cities that experienced reduced Ox during the lockdown usually gained a greater simultaneous PM2.5 decrease than other provinces and cities with an increased Ox. Therefore, we argue that strict VOC control in winter, which has been largely ignored so far, is critical in future policies to mitigate winter haze more efficiently by reducing Ox simultaneously.

An in-depth analysis of the specific evolution of air pollution in a given city can provide a better understanding of the chronic effects of air pollution on human health. In this study, we reported trends in ambient concentrations of particulate matter (PM) and gaseous pollutants [sulfur dioxide (SO2), nitrogen dioxide (NO2), and ozone (O3)] from 1995 to 2017 and PM2.5 composition for the period of 2000-2017 in Guangzhou, Wuhan, Chongqing, and Lanzhou. We provided socio-economic indicators to help explain the pollution trends. SO2 and PM (including PM10 and PM2.5) concentrations showed a downward trend in recent years with the most notable reduction in SO2 in Chongqing and PM2.5 in Guangzhou. There was an overall flat trend for NO2, while O3 showed an upward trend in recent years except in Lanzhou. The majority of PM2.5 mass was SO4 2- (6.0-30 µg/m3) and organic carbon (6.0-38 µg/m3), followed by NO3 - (2.0-12 µg/m3), elemental carbon (2.1-12 µg/m3), NH4 + (1.0-10 µg/m3), K+ (0.2-2.0 µg/m3), and Cl- (0.2-1.9 µg/m3). Except for secondary inorganic aerosols in Wuhan, annual average concentrations of all PM2.5 constituents showed a declining trend after 2013, corresponding to the trend of PM2.5. The secondary sources in PM2.5 were found to be most prominent in Wuhan, while the most abundant EC and Cl- in Lanzhou was attributed to the use of coal. Despite temporal and spatial variabilities across the four cities, coal combustion, traffic emissions, and secondary pollution have been the major sources of PM2.5 pollution. These trends in ambient air pollution levels and PM2.5 composition may help understand changes in health outcomes measured at different times within the time period of 1995-2017 in the four cities.

Panic disorder (PD) is a prevalent anxiety disorder but its neurobiology remains poorly understood. It has been proposed that the pathophysiology of PD is related to an abnormality in a particular neural network. However, most studies investigating resting-state functional connectivity (FC) have relied on a priori restrictions of seed regions, which may bias observations. This study investigated changes in intra and internetwork FC in the whole brain of patients with PD using resting-state functional magnetic resonance imaging. A voxel-wise data-driven independent component analysis was performed on 26 PD patients and 27 healthy controls (HCs).We compared the differences in the intra and internetwork FC between the two groups of subjects using statistical parametric mapping with two-sample t-tests. PD patients exhibited decreased intra-network FC in the right anterior cingulate cortex (ACC) of the anterior default mode network, the left precentral and postcentral gyrus of the sensorimotor network, the right lobule V/VI, the cerebellum vermis, and the left lobule VI of the cerebellum network compared with the HCs. The intra-network FC in the right ACC was negatively correlated with symptom severity. None of the pairs of resting state networks showed significant differences in functional network connectivity between the two groups. These results suggest that the brain networks associated with emotion regulation, interoceptive awareness, and fear and somatosensory processing may play an important role in the pathophysiology of PD.

(1) Background—The aim of the present study was to evaluate the correlation between the temporomandibular joint (TMJ) osseous morphology of normal skeletal pattern individuals with different dental malocclusions by using cone-beam computed tomography (CBCT). (2) Methods—The CBCT images of bilateral TMJs in 67 subjects with skeletal class I and average mandibular angle (26 males and 41 females, age range 20–49 years) were evaluated in this study. The subjects were divided into class I, class II division 1, and class II division 2 according to the molar relationship and retroclination of the maxillary incisors. Angular and linear measurements of TMJ were evaluated and the differences between the groups were statistically analyzed. (3) Results—Intragroup comparisons showed statistical differences for articular eminence inclination, the width of the glenoid fossa, the ratio of the width of the glenoid fossa to the depth of the glenoid fossa, the condylar angle, and the intercondylar angle between the malocclusion groups. The measurements of the glenoid fossa shape showed no significant difference between the left and right sides. Females showed more differences in the morphological parameters of TMJ between the three malocclusion groups than the males. (4) Conclusion—The present study revealed differences in the TMJ osseous morphology between dental class I and class II malocclusions in the normal skeletal pattern.

Volatile organic compounds (VOCs) are important precursors of photochemical pollution. However, a substantial fraction of VOCs, namely, oxygenated VOCs (OVOCs), have not been sufficiently characterized to evaluate their sources in air pollution in China. In this study, a total of 119 VOCs, including 60 OVOCs in particular, were monitored to provide a more comprehensive picture based on different online measurement techniques, proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS) and online gas chromatography/mass spectrometry (GC/MS), at a receptor site in southeastern China during a photochemically active period. Positive matrix factorization (PMF) and photochemical age-based parameterization were combined to identify and quantify different sources of major VOCs during daytime hours, with the advantage of including VOC decay processes. The results revealed the unexpected role of biomass burning (21%) in terms of ozone (O3) formation potential (OFP) when including the contributions of OVOCs and large contributions (30–32%) of biomass burning to aldehydes, as more OVOCs were measured in this study. We argue that biomass burning could significantly enhance the continental atmospheric oxidizing capacity, in addition to the well-recognized contributions of primary pollutants, which should be seriously considered in photochemical models and air pollution control strategies.

Objective: To investigate the roles of serum uric acid (UA), bilirubin (BIL), albumin (ALB), and creatinine (CRE) as major intravascular antioxidants, in benign paroxysmal positional vertigo (BPPV).Methods: The serum levels of UA, BIL, ALB, and CRE were retrospectively analyzed in 70 patients with new-onset idiopathic BPPV and 140 age- and sex-matched healthy controls (HCs).Results: Serum UA, BIL, ALB, and CRE levels were significantly lower in the BPPV group than the HC group. Furthermore, serum levels of BIL and ALB were significantly lower in the BPPV group when compared by sex. Multiple stepwise logistic regression revealed that a reduction in serum ALB was independently related to BPPV (odds ratio = 0.688; 95% confidence interval = 0.607– 0.780). Receiver operating characteristic analyses revealed a cut-off value of 45.15 g/L for ALB with a sensitivity of 74.29% (62.97– 83.07%) and specificity of 73.57% (65.71– 80.18%).Conclusions: Serum levels of UA, BIL, ALB, and CRE were lower in BPPV patients, indicating a lower antioxidant status. Furthermore, a reduction in serum ALB was independently associated with BPPV. These results provide insights into the possible roles of oxidative stress in the pathogenesis of BPPV.

Background Although recent neuroimaging studies have suggested that functional deficits in facial perception are associated with panic disorder (PD), the possibility of cortical thickness and perfusion abnormalities have not been studied in patients with PD. We aimed to investigate alterations in cortical thickness and regional cerebral blood flow (CBF) between PD patients and healthy controls (HCs) using three-dimensional (3D) T1-weighted magnetic resonance imagery (MRI) and 3D arterial spin labeling (ASL) perfusion MRI. Method An automated surface-based method (Cat12) measured the cortical thickness of each subject. Z-score normalization for CBF maps was used to generate Z-score maps. Statistical comparisons were performed using statistical parametric mapping with two-sample t-tests. Results Subjects with PD, unlike HCs, displayed cortical thinning in the right fusiform gyrus (FG). Post hoc analysis also revealed a decreased Z-score in the right FG. There was significant positive correlation between the Z-score and the cortical thickness of the right FG. The cortical thickness and Z-score were negatively correlated with the Panic Disorder Severity Scale and Hamilton Rating Scale for Anxiety scores. Limitations The small sample size may have restricted the identification of additional differences. Other caveats included the use of medication by nine participants. Conclusions These results provide further evidence of the significant role structural and functional deficits in the right FG play in patients with PD. Due to the observed regional specificity, this finding bears important clinical implications for potential treatment strategies.

Water-soluble organic matter (WSOM) represents a critical fraction of fine particles (PM2.5) in the air, but its changing behaviors and formation mechanisms are not well understood yet, partly due to the lack of fast techniques for the ambient measurements. In this study, a novel system for the on-line measurement of water-soluble components in PM2.5, the particle-into-liquid sampler (PILS)-Nebulizer-aerosol chemical speciation monitor (ACSM), was developed by combining a PILS, a nebulizer, and an ACSM. High time resolution concentrations of WSOM, sulfate, nitrate, ammonium, and chloride, as well as mass spectra, can be obtained with satisfied quality control results. The system was firstly applied in China for field measurement of WSOM. The mass spectrum of WSOM was found to resemble that of oxygenated organic aerosol, and WSOM agreed well with secondary inorganic ions. All evidence collected in the field campaign demonstrated that WSOM could be a good surrogate of secondary organic aerosol (SOA). The PILS-Nebulizer-ACSM system can thus be a useful tool for intensive study of WSOM and SOA in PM2.5.

Organic aerosols (OAs), which consist of thousands of complex compounds emitted from various sources, constitute one of the major components of fine particulate matter. The traditional positive matrix factorization (PMF) method often apportions aerosol mass spectrometer (AMS) organic datasets into less meaningful or mixed factors, especially in complex urban cases. In this study, an improved source apportionment method using a bilinear model of the multilinear engine (ME-2) was applied to OAs collected during the heavily polluted season from two Chinese megacities located in the north and south with an Aerodyne high-resolution aerosol mass spectrometer (HR-ToF-AMS). We applied a rather novel procedure for utilization of prior information and selecting optimal solutions, which does not necessarily depend on other studies. Ultimately, six reasonable factors were clearly resolved and quantified for both sites by constraining one or more factors: hydrocarbon-like OA (HOA), cooking-related OA (COA), biomass burning OA (BBOA), coal combustion (CCOA), less-oxidized oxygenated OA (LO-OOA) and more-oxidized oxygenated OA (MO-OOA). In comparison, the traditional PMF method could not effectively resolve the appropriate factors, e.g., BBOA and CCOA, in the solutions. Moreover, coal combustion and traffic emissions were determined to be primarily responsible for the concentrations of PAHs and BC, respectively, through the regression analyses of the ME-2 results.

With the rapid economic development and urbanization of China, haze and photochemical smog events have been frequently observed during the last decade. To explore the temporal and spatial pollution characteristics in Ningbo, a medium-sized coastal city located in the Yangtze River Delta (YRD) in southeast China, 24-h PM2.5 (particulate matter with aerodynamic diameter ≤ 2.5 µm) samples were simultaneously collected at five sites (two urban residential sites, two urban coastal sites, and one suburban site) from winter 2012 to autumn 2013. The average PM2.5 concentration was 53.2 ± 30.4 µg m–3. Furthermore, the concentration exhibited a seasonal variation: It was highest in winter and lowest in summer. The urban residential sites had the highest PM2.5 concentrations, followed by the urban coastal sites, and the suburban site had the lowest concentration. OM (Organic Matters) and secondary inorganic ions (sulfate, nitrate, and ammonium) were the dominant components of the PM2.5. As a coastal city with industrial zones, sources are more complex in Ningbo than in inland cities due to ship emissions and the interactions between land and sea, and the marine and atmospheric environments. Positive matrix factorization (PMF) was used to apportion the particle sources. Nine factors were resolved in this study: secondary nitrate, vehicle exhaust, secondary sulfate, coal combustion, industrial emission, ship emission, dust, biomass burning, and aged sea salt, with average contributions of 26%, 21%, 13%, 12%, 9%, 7%, 5%, 4%, and 3%, respectively. Secondary nitrate and vehicle exhaust were the major sources of PM2.5 pollution in Ningbo. Coal combustion contributed significantly in winter and autumn, whereas sea salt formed a considerable contribution in summer. This study suggests that decreasing the PM2.5 pollution in Ningbo requires not only strategies for reducing local primary sources but also joint inter-regional prevention and the control of air pollution in the YRD.

Rapid economic development and urbanization in China has been concentrated in coastal cities, resulting in haze and photochemical smog issues, especially in the densely-populated Yangtze River Delta. In this study, we explore particulate matter (specifically PM 2.5 ) pollution in a city in Zhejiang Province (Ningbo), chosen to represent a typical, densely-populated urban city with residential and industrial sections. PM 2.5 samples were collected at five sites in four seasons from Dec. 2012 to Nov. 2013. The annual average PM 2.5 mass concentration was 53.2 ± 30.4 μg/m 3 , with the highest concentration in winter and lowest in summer. Among the five sites, PM 2.5 concentration was highest in an urban residential site and lowest in a suburban site, due to effects of urbanization and the anthropogenic influences. The chemical components of PM 2.5 show significant seasonal variation. In addition, secondary transformation was high in Ningbo, with the highest proportion of secondary components found at a suburban site and the lowest at the industrial sites. Ningbo is controlled by five major air masses originating from inland China, from the Bohai Sea, offshore from the southeast, the Yellow Sea, and off the east coast of Korea. The relative contributions of these air masses differ, by season, with the Bohai Sea air mass dominating in winter and spring, the maritime southeast air mass in summer, and the Yellow Sea and coastal Korean air masses dominating in autumn. The continental air mass is associated with a high PM 2.5 concentration, indicating that it is primarily transports primary emissions. In contrast, the concentration ratios among secondary formed pollutants were higher in the maritime air masses, which suggests that sea breezes control temporal and spatial variations of air pollution over coastal cities.

Primary blepharospasm (BPS) is a focal dystonia characterized by involuntary eyelid spasms and blinking. The pathophysiology of BPS remains unclear. Several functional and structural neuroimaging studies have demonstrated abnormalities of sensorimotor structures such as the sensorimotor cortex, the basal ganglia, the thalamus and the cerebellum in BPS patients. However, some of the results of these studies were inconsistent. In addition, the relationship between the motor and sensory structures in patients with BPS still needs to be investigated. Therefore, the purpose of this study was to investigate the abnormal alterations in both the intra-regional brain activities and inter-regional functional connectivities (FC) in patients with BPS using resting-state functional MRI(rs-fMRI) and to explore possible correlations between these rs-fMRI indices and clinical variables. The rs-fMRI images of the two groups of subjects (26 BPS patients and 26 healthy controls) were acquired using a 3.0T MRI scanner. The regional rs-fMRI indices, i.e., the fractional amplitude of the low-frequency fluctuation (fALFF) and the regional homogeneity (ReHo), were computed for all subjects. Then, two-sample t-tests were conducted to assess the significant differences between the two groups of subjects. To investigate the alterations in brain networks, cerebral regions with significant differences were used as regions of interest in the whole brain FC analysis. Compared to the control group, the BPS patients revealed significantly increased fALFF and ReHo values in the right caudate head. Significantly strengthened FC values were observed between the right caudate head and the left striatum and the right supplementary motor area in the BPS group. The fALFF and ReHo values in the right caudate head and the FC values between the right caudate head and the left striatum were positively correlated with the Jankovic Rating Scale sum score. In conclusion, this study indicated that BPS patients have both abnormal intra-regional spontaneous brain activities and inter-regional functional connectivities.

The emission of pollutants is extremely reduced during the annual Chinese Spring Festival (SF) in Shenzhen, China. During the SF, traffic flow drops by ∼ 50 % and the industrial plants are almost entirely shut down in Shenzhen. To characterize the variation in ambient air pollutants due to the Spring Festival effect, various gaseous and particulate pollutants were measured in real time in urban Shenzhen over three consecutive winters (2014–2016). The results indicate that the concentrations of NOx, volatile organic compounds (VOCs), black carbon (BC), primary organic aerosols, chloride, and nitrate in submicron aerosols decrease by 50–80 % during SF periods relative to non-Spring Festival periods, regardless of meteorological conditions. This decrease suggests that these pollutants are mostly emitted or secondarily formed from urban local emissions. The concentration variation in species mostly from regional or natural sources, however, is found to be much less, such as for bulk fine particulate matter (PM2. 5). More detailed analysis of the Spring Festival effect reveals an urgent need to reduce emissions of SO2 and VOCs on a regional scale rather than on an urban scale to reduce urban PM2. 5 in Shenzhen, which can also be useful as a reference for other megacities in China.

Taiwan Strait is a special channel for subtropical East Asian Monsoon and its western coast is an important economic zone in China. In this study, a suburban site in the city of Xiamen on the western coast of Taiwan Strait was selected for fine aerosol study to improve the understanding of air pollution sources in this region. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and an Aethalometer were deployed to measure fine aerosol composition with a time resolution of 5 min from May 1 to 18, 2015. The average mass concentration of PM1 was 46.2 ± 26.3 μg/m3 for the entire campaign. Organics (28.3%), sulfate (24.9%), and nitrate (20.6%) were the major components in the fine particles, followed by ammonium, black carbon (BC), and chloride. Evolution of nitrate concentration and size distribution indicated that local NOx emissions played a key role in high fine particle pollution in Xiamen. In addition, organic nitrate was found to account for 9.0%-13.8% of the total measured nitrate. Positive Matrix Factorization (PMF) conducted with high-resolution organic mass spectra dataset differentiated the organic aerosol into three components, including a hydrocarbon-like organic aerosol (HOA) and two oxygenated organic aerosols (SV-OOA and LV-OOA), which on average accounted for 27.6%, 28.8%, and 43.6% of the total organic mass, respectively. The relationship between the mass concentration of submicron particle species and wind further confirmed that all major fine particle species were influenced by both strong local emissions in the southeastern area of Xiamen and regional transport through the Taiwan Strait.

Danon disease is a genetic deficiency in lysosome-associated membrane protein 2 (LAMP-2), a highly glycosylated constituent of the lysosomal membrane and characterized by a cardiomyopathy, skeletal muscle myopathy, and cognitive impairment. Patients, however, often manifest hepatic abnormalities, but liver function has not been well evaluated and the syndrome is relatively uncommon. Hence, we have taken advantage of a rat that has been deleted of LAMP-2 to study the relative role of LAMP-2 on liver function. Interestingly, rats deficient in LAMP-2 develop a striking increase in serum alkaline phosphatase (ALP) and a decrease in bile flow compared with wild-type littermates. Importantly and by ultrastructural analysis, deficient rats manifest dilated canaliculi that lack microvilli with evidence of bile-containing bodies. Moreover, following bile duct ligation, LAMP-2-deficient rats develop rapid and severe evidence of advanced cholestasis, with an increase in serum bilirubin, as early as 6 h later. In wild-type control rats, multidrug resistance-associated protein 2 (Mrp2) normally concentrates at the bile canalicular membranes to secrete conjugated bilirubin into bile. However, in LAMP-2y/− rats, Mrp2 was detected in hepatocytes compared with other canalicular proteins including P-glycoproteins, dipeptidyl peptidase IV (CD26), and aminopeptidase (CD13). Our data further suggest that LAMP-2 interacts with the membrane cytoskeletal proteins radixin and F-actin in determining the localization of integral membrane proteins.

BACKGROUND Two polymorphisms, -260C>T (rs2569190) and -561C>T (rs5744455), in the CD14 gene have been implicated in susceptibility to cancer. However, the results remain inconclusive. The current meta-analysis was carried out aiming to confirm the function of these two polymorphisms on the susceptibility of cancer. METHODS We collected eligible studies from databases, including PubMed, EMBASE, CNKI, Wanfang, and VIP (Weipu). We used logistic regression calculation to compute odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS After strict selection, 24 studies with 5854 cases and 10339 controls for -260C>T and seven studies with 1809 cases and 7289 controls for -561C>T were finally enlisted into our analysis reference material. Pool results revealed that neither -260C>T, nor -561C>T was found to have any association with overall cancer susceptibility. Nevertheless, when stratified by cancer type, we detected a decreased risk associated with other cancers in a heterozygous model (OR = 0.69, 95% CI = 0.51-0.93, p = 0.014) and a dominant model (OR = 0.70, 95% CI = 0.53-0.93, p = 0.012) for -561C>T. An increased risk was found in other cancers under an allele model (OR = 1.29, 95% CI = 1.03-1.62, p = 0.026), in laryngeal cancer under a dominant model (OR = 1.38, 95% CI = 1.11-1.71, p = 0.003) and for a score ≤ 9 under a recessive model (OR = 1.45, 95% CI = 1.09-1.91, p = 0.009) for -561C>T. CONCLUSIONS In the present study, we conclude that the CD14 -260C>T and -561C>T polymorphisms might not be associated with overall cancer risk. Further studies are encouraged to confirm this conclusion.

The volatility of atmospheric aerosols greatly influences the gas-particle partitioning, chemical mechanisms and lifetime of aerosols. Due to the complex composition, the volatility of organic aerosol is one of the major sources of uncertainty in measuring and modeling ambient aerosols. Despite high aerosol loading in the atmosphere in China, especially in winter, few field measurements were conducted targeting the volatility of ambient organic aerosol (OA). With the deployment of a thermodenuder-aerosol mass spectrometer (TD-AMS) system, the volatility of non-refractory submicron aerosols (NR-PM1) were measured on an island near the coastal line for the regional air in wintertime in southern China. NO3− and Cl− showed the highest volatility in the NR-PM1 chemical species, while SO42− showed the least volatility. Organic aerosol showed a moderate volatility, evaporating at a stable rate (0.57% °C−1) at temperatures lower than 150 °C and keeping a stable volatility when its loading increases, which could be an advantage for parameterization of OA in air quality models. Based on both positive matrix factorization and chemical mass balance modeling of OA composition, biomass burning OA was found to be the most volatile factor, followed by hydrocarbon-like OA and more-oxidized oxygenated OA. By summarizing the OA volatility measured in this study and in the literature, we found that the volatilities of different OA factors at different locations do not have a clear relationship with the OA oxidation state, possibly due to the vague understanding of local OA aging mechanisms and mixing states.

(1) Background: In order to determine the correlation between the inclination of articular eminence (AEI) and the development of temporomandibular disorders (TMDs), a systematic review was performed. (2) Methods: A systematic literature research was conducted between 1946 and January 2020, based on the following electronic databases: PubMed, Cochrane Library, Embase, Medline, Scope, SciELO, and Lilacs. Observational studies, analytical case-control studies, and cohort studies written in English were identified. The articles were selected and analyzed by two authors independently. The PICO format was used to analyze the studies and the Newcastle-Ottawa Scale (NOS) was used to verify the quality of the evidence. (3) Results: Sixteen articles were included in this review, ten case-control studies and six cohort studies. Eight articles (50%) established a positive relation between AEI and TMDs and eight (50%) did not. The scientific quality was medium-low, mainly influenced by the exposure to the risk of bias and the lack of clinical methods with adequate consistency and sensitivity on the diagnosis of TMDs. (4) Conclusions: It is controversial to establish a causal relationship between the TMDs and the AEI in the field of stomatology, due to limited and inconclusive evidence. However, it is suggested that the AEI defined by some specific methods may be associated with some special pathological stages of TMDs. High-quality prospective studies are required to draw any definitive conclusions.

Although China's severe air pollution has become a focus in the field of atmospheric chemistry and the mechanisms of urban air pollution there have been researched extensively, few field sampling campaigns have been conducted at remote background sites in China, where air pollution characteristics on a larger scale are highlighted. In this study, an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS), together with an Aethalometer, was deployed at two of China's national background sites in northern (Lake Hongze site; 33.23° N, 118.33° E; altitude 21 m) and southern (Mount Wuzhi site; 18.84° N, 109.49° E; altitude 958 m) China in the spring seasons in 2011 and 2015, respectively, in order to characterize submicron aerosol composition and sources. The campaign-average PM1 concentration was 36.8 ± 19.8 µg m−3 at the northern China background (NCB) site, which was far higher than that at the southern China background (SCB) site (10.9 ± 7.8 µg m−3). Organic aerosol (OA) (27.2 %), nitrate (26.7 %), and sulfate (22.0 %) contributed the most to the PM1 mass at NCB, while OA (43.5 %) and sulfate (30.5 %) were the most abundant components of the PM1 mass at SCB, where nitrate only constituted a small fraction (4.7 %) and might have contained a significant amount of organic nitrates (5–11 %). The aerosol size distributions and organic aerosol elemental compositions all indicated very aged aerosol particles at both sites. The OA at SCB was more oxidized with a higher average oxygen to carbon (O ∕ C) ratio (0.98) than that at NCB (0.67). Positive matrix factorization (PMF) analysis was used to classify OA into three components, including a hydrocarbon-like component (HOA, attributed to fossil fuel combustion) and two oxygenated components (OOA1 and OOA2, attributed to secondary organic aerosols from different source areas) at NCB. PMF analysis at SCB identified a semi-volatile oxygenated component (SV-OOA) and a low-volatility oxygenated component (LV-OOA), both of which were found to be secondary species and could be formed from precursors co-emitted with BC. Using the total potential source contribution function model, the likely source areas of the major PM1 components at both sites were a on large regional scale in East Asia. The possible sources may include not only emissions from the Chinese mainland but also emissions from ocean-going cargo ships and biomass burning in neighboring countries.

The strong spectral dependence of light absorption of brown carbon (BrC) aerosol is regarded to influence aerosol's radiative forcing significantly. The Absorption Angstrom Exponent (AAE) method has been widely used in previous studies to attribute light absorption of BrC at shorter wavelengths for ambient aerosols, with a theoretical assumption that the AAE of "pure" black carbon (BC) aerosol equals to 1.0. In this study, the AAE method was applied to both urban and rural environments in the Pearl River Delta (PRD) region of China, with an improvement of constraining the realistic AAE of "pure" BC through statistical analysis of on-line measurement data. A three-wavelength photo-acoustic soot spectrometer (PASS-3) and aerosol mass spectrometers (AMS) were used to explore the relationship between the measured AAE and the relative abundance of organic aerosol to BC. The regression and extrapolation analysis revealed that more realistic AAE values for "pure" BC aerosol (AAEBC) were 0.86, 0.82, and 1.02 between 405 and 781 nm, and 0.70, 0.71, and 0.86 between 532 and 781 nm, in the campaigns of urbanwinter, urbanfall, and ruralfall, respectively. Roadway tunnel experiments were conducted and the results further confirmed the representativeness of the obtained AAEBC values for the urban environment. Finally, the average light absorption contributions of BrC (± relative uncertainties) at 405 nm were quantified to be 11.7 % (±5 %), 6.3 % (±4 %), and 12.1 % (±7 %) in the campaigns of urbanwinter, urbanfall, and ruralfall, respectively, and those at 532 nm were 10.0 % (±2 %), 4.1 % (±3 %), and 5.5 % (±5 %), respectively. The relatively higher BrC absorption contribution at 405 nm in the ruralfall campaign could be reasonably attributed to the biomass burning events nearby, which was then directly supported by the biomass burning simulation experiments performed in this study. This paper indicates that the BrC contribution to total aerosol light absorption at shorter wavelengths is not negligible in the highly urbanized and industrialized PRD region.

The Pearl River Delta (PRD) of China, which has a population of more than 58 million people, is one of the largest agglomerations of cities in the world and had severe PM 2.5 pollution at the beginning of this century. Due to the implementation of strong pollution control in recent decades, PM 2.5 in the PRD has continuously decreased to relatively lower levels in China. To comprehensively understand the current PM 2.5 sources in the PRD to support future air pollution control strategies in similar regions, we performed regional-scale PM 2.5 field observations coupled with a state-of-the-art source apportionment model at six sites in four seasons in 2015. The regional annual average PM 2.5 concentration based on the 4-month sampling was determined to be 37 µg m−3 , which is still more than 3 times the WHO standard, with organic matter (36.9 %) and SO 4 2 - (23.6 %) as the most abundant species. A novel multilinear engine (ME-2) model was first applied to a comprehensive PM 2.5 chemical dataset to perform source apportionment with predetermined constraints, producing more environmentally meaningful results compared to those obtained using traditional positive matrix factorization (PMF) modeling. The regional annual average PM 2.5 source structure in the PRD was retrieved to be secondary sulfate (21 %), vehicle emissions (14 %), industrial emissions (13 %), secondary nitrate (11 %), biomass burning (11 %), secondary organic aerosol (SOA, 7 %), coal burning (6 %), fugitive dust (5 %), ship emissions (3 %) and aged sea salt (2 %). Analyzing the spatial distribution of PM 2.5 sources under different weather conditions clearly identified the central PRD area as the key emission area for SO2 , NOx , coal burning, biomass burning, industrial emissions and vehicle emissions. It was further estimated that under the polluted northerly air flow in winter, local emissions in the central PRD area accounted for approximately 45 % of the total PM 2.5 , with secondary nitrate and biomass burning being most abundant; in contrast, the regional transport from outside the PRD accounted for more than half of PM 2.5 , with secondary sulfate representing the most abundant transported species.

Purpose: This study explored the clinical characteristics, diagnosis and treatments of primary blepharospasm. Methods: In this retrospective analysis, 100 patients with blepharospasm were enrolled. Data were collected from medical records and face-to-face interviews with patients and their families. Results: The age of onset was 56.4 ± 2.7 (range, 32-76 years). The duration between onset and accurate diagnosis was 38.7 ± 36.0 months (range, 2-120 months). Dry eyes occurred in 54% of the patients. The initial diagnostic accuracy was 10%. Dry eye syndrome, conjunctivitis/keratitis and myasthenia gravis caused the most confusion in the differential diagnosis. Regular botulinum toxin type A injections improved both eyelid spasms and subjective ocular symptoms in all patients. Conclusions: Regular botulinum toxin type A injections improved both eyelid spasms and subjective ocular symptoms in blepharospasm patients. The differentiation of primary blepharospasm differentiation from dry eye syndrome, conjunctivitis/keratitis and myasthenia gravis must be improved.

Primary blepharospasm (BPS) is a focal dystonia characterized by involuntary blinking and eyelid spasms. The pathophysiology of BPS remains unclear. Several neuroimaging studies have suggested dysfunction of sensory processing and sensorimotor integration, but the results have been inconsistent. This study aimed to determine whether patients with BPS exhibit altered functional brain connectivity and to explore possible correlations between these networks and clinical variables. Twenty-five patients with BPS and 25 healthy controls were enrolled. We found that the patient group exhibited decreased connectivity within the sensory-motor network (SMN), which involved regions of the bilateral primary sensorimotor cortex, supplementary motor area (SMA), right premotor cortex, bilateral precuneus and left superior parietal cortex. Within the right fronto-parietal network, decreased connections were observed in the middle frontal gyrus, dorsal lateral prefrontal cortex and inferior frontal gyrus. Regarding the salience network (SN), increased connectivity was observed in the left superior frontal gyrus and middle frontal gyrus. These findings suggest the involvement of multiple neural networks in primary BPS.

Background The purpose of this study was to evaluate orthodontic debonding methods by comparing the surface roughness and enamel morphology of teeth after applying two different debonding methods and three different polishing techniques. Methods Forty eight human maxillary premolars, extracted for orthodontic reasons, were randomly divided into three groups. Brackets were bonded to teeth with RMGIC (Fuji Ortho LC, GC, Tokyo, Japan) (two groups, n = 18 each) after acid etching (30s), light cured for 40 s, exposed to thermocycling, then underwent 2 different bracket debonding methods: debonding pliers (Shinye, Hangzhou, China) or enamel chisel (Jinzhong, Shanghai, China); the third group (n = 12) comprised of untreated controls, with normal enamel surface roughness. In each debonded group, three cleanup techniques (n = 6 each) were tested, including (I) diamond bur (TC11EF, MANI, Tochigi, Japan) and One-Gloss (Midi, Shofu, Kyoto, Japan), (II) a Super-Snap disk (Shofu, Kyoto, Japan), and (III) One-Gloss polisher. The debonding methods were compared using the modified adhesive remnant index (ARI, 1–5). Cleanup efficiencies were assessed by recording operating times. Enamel surfaces were qualitatively and quantitatively evaluated with scanning electron microscopy (SEM) and surface roughness tester, respectively. Two surface roughness variables were evaluated: Ra (average roughness) and Rz (10-point height of irregularities). Results The ARI scores of debonded teeth were similar with debonding pliers and enamel chisel (Chi-square = 2.19, P > 0.05). There were significant differences between mean operating time in each group (F = 52.615, P

Metastasis, a cascade of events beginning with epithelial-to-mesenchymal transition (EMT), is the main cause of cancer-related mortality. EMT endows circulating cancer cells (CTCs) with invasive and anti-apoptotic properties. These transitioning cells leave the primary tumor site and travel through the circulation to populate remote organs, even prior to the onset of clinical symptoms. During this journey, CTCs activate platelets, which in turn secrete α-granules. These α-granules contain high levels of transforming growth factor-β (TGF-β) and platelet-derived growth factor (PDGF), both considered to be powerful activators of EMT. Recently, regular aspirin use was associated with a reduced risk of cancer metastasis. However, the molecular mechanism underlying the chemotherapeutic effects of aspirin on metastasis has not been fully elucidated. As platelets lack a nucleus, regular aspirin use may exert long-lasting effects on irreversible inhibition of cyclooxygenase (COX)-1 and, subsequently, the secretion of α-granules, which contributes to the maintenance of the EMT state of CTCs. Thus, we hypothesized that the inhibition of platelet-induced EMT of CTCs through the COX-1 signaling pathway may contribute to the intriguing antimetastatic potential of aspirin.

Cancers are thought to be the result of accumulated gene mutations in cells. Carcinomas, which are cancers arising from epithelial tissues usually go through several stages of development: atypical hyperplasia, carcinoma in situ and then invasive carcinoma, which might further metastasize. However, we think that the present pathological data are enough to prove that there might be an alternative way of carcinogenesis. We propose that majority of invasive cancers arise in the connective tissue stroma de novo, from the misplaced epithelial stem cells which come to the wrong land of connective tissue stroma by accident. The in situ carcinomas, which are mostly curable, should not be considered genuine cancer, but rather as quasi-cancer. We design this new theory of carcinogenesis as the stem cell misplacement theory (SCMT). Our SCMT theory chains together other carcinogenesis theories such as the inflammation-cancer chain, the stem cell theory and the tissue organization field theory. However, we deny the pathway of somatic mutation theory as the major pathway of carcinogenesis.

The effects of black carbon (BC) aerosol on climate warming have been the study focus in the recent decade, and the reduction of BC is now expected to have significant near-term climate change mitigation. Large uncertainties of BC optical properties, however, still exist and seriously restrict the ability to quantify BC's climate effects. In this study, advanced instrumentation (a three-wavelength photoacoustic soot spectrometer (PASS-3) and a single particle soot photometer (SP2)) were used to measure black carbon aerosol and analyze its optical properties in a mega-city in South China, Shenzhen, during the summer of 2011. The results indicated that the average BC mass concentration was 4.0 ± 3.1 μg m −3 during the campaign, accounting for ∼11% of the total PM 2.5 mass concentration. The PM 2.5 light absorption at 405, 532 and 781 nm was 37.1 ± 28.1, 25.4 ± 19.0 and 17.6 ± 12.9 Mm −1 , respectively. The average absorption Angstrom exponent of PM 2.5 in visual spectrum (AAE 405–781 nm ) was 1.1 ± 0.1 during the campaign, indicating that the light absorbing carbon mainly came from vehicular emissions, with little contributions from biomass burning emissions. The mass absorption efficiency (MAE) of BC at 532 nm ranged from 5.0 to 8.5 m 2 g −1 during the campaign, with an average of 6.5 ± 0.5 m 2 g −1 , and showed an obvious diurnal pattern with high values in the daytime. The average percentage of internally mixed BC was 24.3 ± 7.9% during the campaign, showing significant positive correlation relationship with the MAE of BC. More quantitative data analysis indicated that the internally mixed BC would amplify MAE by about 7% during the campaign, which stands in accordance with the new finding of a very recent Science magazine paper ( Cappa et al., 2012 ) that the BC absorption enhancement due to internal mixing in the real atmosphere is relatively low, in apparent contrast to theoretical model predictions.

On-line measurement of the chemical composition and size distribution of submicron aerosol particles (PM1) was conducted in urban Shenzhen, China, using a state-of-the-art high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) during the 2011 Shenzhen Universiade (August 3-September 22, 2011). The mean PM1 mass concentration measured was 51.1±32.6 μm-3 during the campaign, with organic aerosol (OA) accounting for 37.9% of the total mass, followed by sulfate (37.1%), ammonium (11.9%), black carbon (6.6%, measured by a single particle soot photometer, SP2), nitrate (5.8%) and chloride (0.6%). The average size distributions of the species (except black carbon) all had a peak at ~550 nm in vacuum aerodynamic diameter. The size distribution pattern of OA was broader at smaller sizes (100-200 nm), indicating an obvious contribution from local primary sources. Calculations based on high-resolution organic mass spectrum showed that, C, H, O, and N on average contributed 34.0, 53.2, 12.0, and 0.8% to the total atomic numbers of OA, respectively, which corresponded to an OM/OC ratio (the ratio of organic mass over organic carbon mass) of 1.66±0.16. Three components of OA were identified by positive matrix factorization (PMF) analysis on the high-resolution organic mass spectral dataset, including a hydrocarbon-like (HOA), a semi-volatile oxygenated (SV-OOA) and a low-volatility oxygenated (LV-OOA) organic aerosol, which on average accounted for 31.3, 39.8, and 28.9% of the total organic mass, respectively. This indicated that OA was dominated by secondary organic aerosol (represented by the sum of SV-OOA and LV-OOA). Analysis on the PM1 chemical compositions and size distributions in different episodes according to air mass sources showed that, the mean PM1 mass concentration during the Universiade game days was 60.7% lower than that during the whole observation period. This was a combined result of a favorable meteorological condition with air masses coming from the sea and the emission control measures like the restriction of high-emission old vehicles.

Cancer has been considered to be the result of accumulated gene mutations, which result in uncontrolled cell proliferations for a long time. Cancers are also regarded to be capable of immune evasion. Furthermore, resistance to apoptosis was recognized as an important trait of cancer in the last score of years. However, there are numerous paradoxical issues in this whole set of theory. For example, there is no known set of genes of which mutations are responsible for human cancers. As for the trait of ‘resistance to apoptosis’, the fact is that cancer has increased frequency of apoptosis. The more malignant the tumour is, the more apoptosis shows. In this study, we propose a new theory that apoptosis plays a key role in the malignant progression and metastasis of cancer. The growth of tumour is the difference between tumour cell proliferation and attrition plus the hyperplastic growth of stroma. Increased and unpreventable death caused by innate or environmental factors such as ischaemia and inflammation drives the tumour cells to proliferate relentlessly, move to new lands to establish colonies. In short, increased cell death is the origin of malignancy.

The Yangtze River Delta (YRD) region is one of the most economically developed regions of China and characterized by high level of urbanization, which comes with the consequence of severe deterioration of its atmospheric environment in a large regional scale. In order to characterize the fine particle pollution features representative for YRD, especially for the abundant and complex carbonaceous component, we deployed advanced on-line measurement at a regional site in Jiaxing in the central YRD area during June 29–July 15 (the summer campaign) and December 11–23 (the winter campaign), with a high resolution aerosol mass spectrometer (AMS) and a single particle soot photometer (SP2). The mean PM1 mass concentration was observed to be 32.9 μg m−3 in summer, with organic matter (OM) and black carbon (BC) contributing 32.1 and 9.1%, respectively, and 41.9 μg m−3 in winter, with OM and BC contributing 30.3 and 16.9%, respectively. The O/C ratio of OM, an indicator for the oxidation level of organic aerosol, was calculated to be 0.28 in summer and 0.33 in winter, and the number fraction of internally mixed BC particles (NIB), an indicator for the aging level of BC, was calculated to be 0.51 in summer and 0.53 in winter. Two popular independent methods were used to estimate the amount of secondary organic aerosol (SOA) in Jiaxing: one is the positive matrix factorization method utilizing the high resolution aerosol mass spectra (the AMS-PMF method), and the other is the simple OC/EC ratio method (the OC/EC method). The AMS-PMF method estimated that SOA averagely accounted for 68.3 and 30.2% of OM in summer and winter, respectively. The SOA amount estimated by the OC/EC method was found to agree well with that by the AMS-PMF method in summer, but strong biomass burning events in winter made the OC/EC method over-estimate SOA largely. The seasonal variation of SOA indicates that SOA production in YRD is more determined by ambient temperatures than by precursors.

Background The origin and heterogeneity of hepatic progenitor cells (HPCs) remain unclear. This study aimed to investigate the involvement of epithelial-mesenchymal transition (EMT) in the histogenesis of HPCs. Methods Surgical liver specimens from patients with HBV-related hepatitis and cirrhosis were investigated with double immunofluorescence labeling to detect antigens associated with HPCs and EMT. Ductular reactions were subjected to quantitative reverse transcription PCR following isolation by laser capture microdissection. Electron microscopic examination was performed to find an ultrastructural evidence of EMT. Results The number of EpCAM-positive HPCs was proportional to the disease severity. The S100A4 expression of HPCs was firstly observed in mild hepatitis and increased significantly in moderate hepatitis, but decreased in severe hepatitis and cirrhosis. The levels of MMP-2, Twist, and Snail increased in direct proportion to the number of HPCs. Some hepatocytes adjacent to portal tracts in cirrhosis showed positivity for MMP-2. Although CK7 and E-cadherin levels decreased in mild and moderate hepatitis, HPCs re-expressed both of them in severe hepatitis and cirrhosis. However, HPCs expressed neither vimentin nor αSMA. The relative mRNA expression levels of EpCAM and EMT-associated markers supported immunohistochemical results. Electron microscopic examination demonstrated the existence of intercellular junctions among HPCs, cholangiocytes, and intermediate hepatocyte-like cells. Conclusion We provided preliminary evidence for the involvement of EMT in the histogenesis of HPCs from cholangiocytes in HBV-related liver diseases. HPCs may re-transdifferentiate into hepatocytes, and the differentiation direction depends, at least in part, on interactions between HPCs and the surrounding microenvironment, especially the non-resolving inflammation caused by HBV infection.

Knowledge of particle number size distribution (PND) and new particle formation (NPF) events in Southern China is essential for mitigation strategies related to submicron particles and their effects on regional air quality, haze, and human health. In this study, seven field measurement campaigns were conducted from December 2013 to May 2015 using a scanning mobility particle sizer (SMPS) at four sites in Southern China, including three urban sites and one background site. Particles were measured in the size range of 15-615nm, and the median particle number concentrations (PNCs) were found to vary in the range of 0.3×104-2.2×104cm-3 at the urban sites and were approximately 0.2×104cm-3 at the background site. The peak diameters at the different sites varied largely from 22 to 102nm. The PNCs in the Aitken mode (25-100nm) at the urban sites were up to 10 times higher than they were at the background site, indicating large primary emissions from traffic at the urban sites. The diurnal variations of PNCs were significantly influenced by both rush hour traffic at the urban sites and NPF events. The frequencies of NPF events at the different sites were 0%-30%, with the highest frequency occurring at an urban site during autumn. With higher SO2 concentrations and higher ambient temperatures being necessary, NPF at the urban site was found to be more influenced by atmospheric oxidizing capability, while NPF at the background site was limited by the condensation sink. This study provides a unique dataset of particle number and size information in various environments in Southern China, which can help understand the sources, formation, and the climate forcing of aerosols in this quickly developing region, as well as help constrain and validate NPF modeling.

The efficacy of ursodeoxycholic acid (UDCA) on long-term outcome of primary biliary cirrhosis (PBC) has been less documented in Chinese cohort. We aimed to assess the therapeutic effect of UDCA on Chinese patients with PBC. In the present study, 67 patients with PBC were treated with UDCA (13-15 mg·kg(-1)·day(-1)) and followed up for 2 years to evaluate the changes of symptoms, laboratory values and histological features. As the results indicated, fatigue and pruritus were obviously improved by UDCA, particularly in patients with mild or moderate symptoms. The alkaline phosphatase and γ-glutamyl transpetidase levels significantly declined at year 2 comparing to baseline values, with the most profound effects achieved in patients at stage 2. The levels of alanine aminotransferase and aspartate aminotransferase significantly decreased whereas serum bilirubin and immunoglobulin M levels exhibited no significant change. Histological feature was stable in patients at stages 1-2 but still progressed in patients at stages 3-4. The biochemical response of patients at stage 2 was much better than that of patients at stages 3-4. These data suggest that, when treated in earlier stage, patients in long-term administration of UDCA can gain favorable results not only on symptoms and biochemical responses but also on histology. It is also indicated that later histological stage, bad biochemical response and severe symptom may be indicators of poor prognosis for UDCA therapy.

In this study, we investigate the influence of long-range transport (LRT) episodes brought in by cold front on the concentration levels of PM 2.5 , major aerosol constituents, organic tracers, and PM 2.5 source characteristics in Hong Kong, China. PM 2.5 samples were collected during January–March 2004 and January–March 2005 and analyzed for major constituents and organic tracer species. Synoptic weather conditions and characteristics of common air pollutants were used to categorize the sampling days to three groups, i.e., groups mainly affected by local emissions or regional transport (RT) or cold front LRT. Concentrations of PM 2.5 mass and its major constituents during cold-front days were lower than those during RT-dominated periods but higher than those during local emissions-dominated periods. Source apportionment using chemical mass balance (CMB) indicates that vehicular exhaust was a significant primary OC source of mainly local emissions, making average contributions of 1.82, 1.50, and 2.39 μg C m − 3 to OC in the local, LRT, and RT sample groups, respectively. During cold front periods, primary OC concentrations attributable to biomass burning and coal combustion were approximately triple and double, respectively, those during periods dominated by local emissions. Suspended dust, a minor primary OC source (0.24–0.40 μg C m − 3 ), also showed increased contribution during cold fronts. The unexplained OC by CMB (i.e., total OC minus apportioned primary OC), an approximate indicator for secondary OC, was a significant fraction of OC (> 48%) and its mass concentration was much higher in the cold front LRT and RT sample groups (6.37 and 9.48 μg C m − 3 ) than in the local sample group (3.8 μg C m − 3 ). Source analysis as well as tracer concentration variation shows that biomass burning OC and water soluble organic carbon (WSOC) were correlated, suggesting biomass burning as a significant contributor to WSOC.

Laugier–Hunziker syndrome (LHS) is an acquired pigmentary condition affecting lips, oral mucosa and acral area, frequently associated with longitudinal melanonychia. There is neither malignant predisposition nor underlying systemic abnormality associated with LHS. Herein, we present three uncommon cases of LHS with possibly new feature of nail pigmentation, which were diagnosed during the past 2 years. We also review the clinical and histological findings, differential diagnosis, and treatment of the syndrome in published literature.

A one-year-long observation on major organic compounds in PM 2.5 was performed in a coastal mega-city in South China, Shenzhen, in order to gain information of their ambient concentration levels and the implications for sources. The compounds identified included alkanes, PAHs, hopanes, fatty acids and dicarboxylic acids, whose annual average concentrations during the year were 56.0, 14.8, 2.51, 253, and 25.2 ng m − 3 , respectively. The seasonal molecular distributions of these organic compounds were discussed to explore their contributing sources in Shenzhen. Conclusively, alkanes and PAHs had the dominant source of fossil fuel combustion, although alkanes also had significant contribution from plant wax (~ 16%). The hopane series distributions further indicated that vehicle emissions were the dominant fossil fuel combustion source for PM 2.5 in Shenzhen. Cooking emissions were inferred to be the most possible main source for fatty acids, while both primary and secondary origins were implied for azelaic acid, the dominant one in the dicarboxylic acids identified. Most of the organic compounds analyzed showed a size distribution pattern peaking at 0.32–0.56 or 0.56–1 μm in the accumulation mode, except that the cooking-related organic acids showed implication of a coarse mode-dominated pattern.

Hepatitis C virus (HCV) infection in the uterus is a significant path of vertical HCV transmission. Some studies consider vertical HCV transmission in the uterus as the result of maternal blood leakage into infant blood, whereas others theorize that HCV is transmitted by the mother to the infant through cells constituting the placenta barrier. Although trophoblasts play an important role in the placenta barrier, no definitive evidence has been presented to prove that cytotrophoblasts can be infected with HCV. The current study investigated whether or not these can be infected with HCV by conducting an experiment, in which cultured human cytotrophoblasts were infected with HCV in vitro. The results were analyzed using reverse transcription polymerase chain reaction (RT-PCR), ultrastructural characteristic changes under an electron microscope, and immunoelectron microscopy. HCV RNA in the supernatant of the cultured medium of the infected group was intermittently detected during the 16-day incubation period using RT-PCR. Under an electron microscope, the ultrastructures of infected human cytotrophoblasts were markedly different from normal cells, demonstrating lysosomal hyperplasia, rough endoplasmic reticulum, decreased lipid droplets, presence of vacuoles, and the appearance of HCV-like particles. Using immunoelectron microscopy, HCV-like particles conjoined with golden granules were also observed. Based on the data, the current study concludes that HCV infects a human cytotrophoblast cultured in vitro; moreover, its ultrastructure changes dramatically upon infection.

Shanghai, with a population of over 20 million, is the largest mega-city in China. Rapidly increasing industrial and metropolitan emissions have deteriorated its air quality in the past decades, with fine particle pollution as one of the major issues. However, systematic characterization of atmospheric fine particles with advanced measurement techniques has been very scarce in Shanghai. During 2010 Shanghai World Expo, we deployed a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and a single particle soot photometer (SP2) in urban Shanghai between 15 May and 10 June 2010 to measure fine particles with a high time resolution. The 4-min resolution PM1 mass concentration ranged from 5.5 to 155 μg m−3, with an average of 29.2 μg m−3. On average, sulfate and organic matter (OM) were the most abundant PM1 components, accounting for 33.3 and 28.7% of the total mass, respectively, while the fraction of nitrate showed an increasing trend with the increasing PM1 loading, indicating the photochemical nature of high fine particle pollution in Shanghai. Taking advantage of HR-ToF-AMS and SP2, OM was found to have an average OM/OC ratio (organic matter mass/organic carbon mass) of 1.55 and black carbon (BC) had an average number fraction of internally mixed BC of 41.2%. Positive matrix factorization (PMF) analysis on the high resolution organic mass spectral dataset identified a hydrocarbon-like (HOA), a semi-volatile oxygenated (SV-OOA), and a low-volatility oxygenated (LV-OOA) organic aerosol component, which on average accounted for 24.0, 46.8, and 29.2% of the total organic mass, respectively. The diurnal patterns of them with interesting time delay possibly implied a photochemical oxidizing process from HOA (and/or its concurrently emitted gaseous organic pollutants) to SV-OOA to LV-OOA. Back trajectory analysis indicated that the northwesterly continental air mass represented the most severe pollutant regional transport condition with the highest nitrate and SV-OOA fractions. In addition, the results in Shanghai were compared with similar measurements performed recently in other mega-cities in the world.

Black carbon (BC) is the dominant light-absorbing aerosol component in the atmosphere and plays an important role in atmospheric pollution and climate change. The light-absorbing properties of BC rely on particle size, shape, composition, as well as the BC mixing state with other aerosol components, thus more thorough exploration of BC aerosol characteristics is critical in understanding its atmospheric sources and effects. In this study, a newly-developed Single Particle Soot Photometer (SP2) was deployed in Shenzhen, China, for continuous BC measurements to obtain the important information about size distribution and mixing state of BC under severe air pollution conditions of China. The mean BC mass concentrations were found to be 6.0 and 4.1 μg m−3 at an urban site (UT) in the fall and winter, respectively, while it is much lower (2.6 μg m−3) at a rural site (BG) in the fall. The mass size distributions of BC in volume equivalent diameter (VED) at the three sites showed a similar lognormal pattern, with the peak diameter at BG (222 nm) slightly larger than at the UT (210 nm) site. As to mixing state, the average percentage of internally mixed BC at the UT site was detected to be 40% and 46% in the fall and winter, respectively, while that at the BG site in the fall was only a slightly higher (47%), which implies that fresh local fossil fuel combustions were still significant at this rural site. The analysis of extremely high BC concentrations (>20 μg m−3) at UT indicates that they were a complex of comparable contributions from both local fresh emissions and regional transport under unfavorable meteorology. Other characteristics of BC aerosol and their influencing factors in Shenzhen were also discussed.

Background The clear cell/signet-ring cell variant of cutaneous squamous cell carcinoma (cSCC) is extremely rare. Its carcinogenesis has consistently been linked to ultraviolet radiation and HPV in the literature. However, there is little definite information about the contribution of diabetes mellitus (DM) to cSCC. Case presentation A 78-year-old Chinese woman with type 2 DM presented with a mushroom-like lump in her right thigh. Histological findings revealed that the lesion was mainly composed of clear cells and signet-ring cells. The septa of vacuoles in cytoplasm displayed positivity for periodic acid schiff (PAS) and cytokeratins such as AE1/AE3, CK5/6, CK14, and CK19. Malignant cells did not express CK7, CK8, CK18, CK20, p16, p53, or c-erbB-2, and the Ki-67 index was less than 5 %. We further explored the etiology of clear cell/signet-ring cell cSCC using human papillomavirus (HPV) type-specific PCR and genotyping and confirmed that the patient was not infected with HPV. Nucleus positivity for p63 indicated the involvement of the p53 family in the lesion. Meanwhile, the expression of fibroblast growth factor receptor-2 (FGFR2), a downstream effector of p63, was upregulated in tumor cells. Conclusions This study provides the first report on the clear cell/signet-ring cell variant of cSCC found in the right thigh of a patient with type 2 DM. Metabolic imbalance in addition to conventional pathogens such as UV and HPV may contribute to the development of the lesion via p63/FGFR2 axis.

New particle formation (NPF) events have been recognized as an important process contributing to the cloud condensation nuclei (CCN) formation. In this study, measurement of NPF and predicted number concentrations of CCN using κ-Kohler theory were analyzed to assess the contribution of NPF to possible CCN. The particle growth rates of NPF events were categorized to two types: sulfur-rich (condensation and neutralization of sulfuric acid dominating net growth rate) and sulfur-poor cases. The growth rates for the sulfur-poor events were about 80% larger than those of the sulfur-rich cases on average. NPF events increased the CCN number concentrations by 0.4–6 times in the megacity area of Beijing. The enhancement ratios (the ratio of CCN number concentrations when obvious particle growth ended to that when it started during NPF events) were high for large supersaturation ( S ). For example, it was about 30–50% higher under S = 0.86% than under S = 0.07%. The enhancement ratios exhibited similar seasonal variation as the growth rates with a larger value in summer than other seasons, which suggested that growth rate was a key factor in the conversion of NPF to possible CCN. The enhancement ratios were higher during the sulfur-poor NPF events with larger growth rates mainly contributed by organic species, indicating that organic species were the dominant chemical contributor in facilitating the conversion of newly formed particles to possible CCN in the Beijing Megacity.

Accumulation and activation of myofibroblasts are the hallmark of progressive pulmonary fibrosis, and the resident fibroblasts are the major source of myofibroblasts. However, the key factors involved in the transformation of fibroblasts are unknown. Pulmonary microvascular endothelial cells (PMVECs), major effector cells against pathogenesis in early stages of the disease, can secrete cytokines to induce the differentiation of mesenchymal cells. We speculated that PMVECs could secrete pro-fibrotic cytokines and promote the transformation of fibroblasts into myofibroblasts. Accordingly, we established a co-culture system with PMVECs and fibroblasts to examine the specific transformation and collagen synthesis of the co-cultured fibroblasts by FACS and Western blot, prior to and after treatment with neutralizing antibodies against transforming growth factor-beta1 (TGF-β1) and connective tissue growth factor (CTGF). We also analyzed expression of TGF-β1 and CTGF in PMVECs. The synthesis and secretion of TGF-β1 and CTGF protein were up-regulated in PMVECs isolated from bleomycin (BLM)-treated rats, most prominently at 7 days post-instillation. We showed that the PMVECs isolated from BLM-induced rats could induce the transformation of normal fibroblasts and their secretion of collagen I, which was inhibited by both neutralizing anti-TGF-β1 and anti-CTGF antibodies. Therefore, up-regulation of TGF-β1 and CTGF in PMVECs plays an important role in activation, transformation, and collagen synthesis of fibroblasts; in particular, these effects in PMVECs are likely to be the key factors for activation and stimulation of static fibroblasts in lung interstitium in early stages of pulmonary fibrosis disease.

The Pearl River Delta (PRD) region in South China is one of the most economically developed regions in China, but it is also noted for its severe air pollution due to industrial/metropolitan emissions. In order to continuously improve the understanding and quantification of air pollution in this region, an intensive campaign was executed in PRD during October–November 2008. Here, we report and analyze Aerodyne High-Resolution Aerosol Mass Spectrometer measurements at Kaiping, a rural site downwind of the highly-polluted central PRD area, to characterize the general features of submicron particulate pollution in the regional air. The mean measured PMsub>1 mass concentration was 33.1±18.1 μg m[superscript −3] during the campaign and composed of organic matter (33.8%), sulfate (33.7%), ammonium (14.0%), nitrate (10.7%), black carbon (6.7%), and chloride (1.1%), which is characterized by high fractions of inorganic ions due to huge emissions of SO[subscript 2] and NO[subscript x] in PRD. The average size distributions of the species (except BC) were all dominated by an accumulation mode peaking at ~450 nm in vacuum aerodynamic diameter. Calculations based on high-resolution organic mass spectra indicate that C, H, O, and N on average contributed 56.6, 7.0, 35.1, and 1.3% to the total organic mass, respectively, corresponding to an organic matter mass to organic carbon mass ratio (OM/OC) of 1.77±0.08. Based on the high-resolution organic mass spectral dataset observed, Positive Matrix Factorization (PMF) analysis differentiated the organic aerosol into three components, i.e., biomass burning (BBOA) and two oxygenated (LV-OOA and SV-OOA) organic aerosols, which on average accounted for 24.5, 39.6 and 35.8% of the total organic mass, respectively. The BBOA showed strong features of biomass burning emissions and has been mainly attributed to the open field burning of crop residues after the harvest in PRD rural areas. The LV-OOA and SV-OOA were found to correspond to more aged (and thus less-volatile) and fresher (and semi-volatile) secondary organic aerosol (SOA), respectively. Analysis of meteorological influence supported that regional transport from the central PRD area was the major origin of the PM[subscript 1] observed at the Kaiping site., National High-Tech R&D (863) Plan of China (2006AA06A308), National Natural Science Funds for Distinguished Young Scholars (21025728), National Natural Science Foundation (China) (40805049), National Natural Science Foundation (China) (20777001)

South China is one of the major regions suffering from acid rain in the world, especially for its urban environments. However, long-term and comprehensive studies on rainwater chemistry in this region have been scarce in the literature. In order to characterize the current acid rain status in South China, a total of 208 rainfall events were collected and measured systematically at an urban site in Shenzhen, a mega-city on the southeast coast of China, from 2005 to 2009. The volume-weighted mean (VWM) pH was observed to be 4.56 during the five years, with an acid rain frequency of 84.6%. SO42− was the most abundant ionic species, followed by Ca2+, NH4+, H+, NO3−, Cl−, Na+, Mg2+, K+ and F− in sequence. Formic, acetic and oxalic acids together contributed 2.32% to the total organic carbon (TOC) content and 2.86% to the total free acidity. SO42−, NO3−, Ca2+, NH4+ and TOC presented a seasonal trend of being lower in summer and higher in winter, while the other species did not show clear seasonal patterns. Based on the dataset, the sources of the species in rainwater in Shenzhen were explored using different statistical techniques, which indicated strong impact of anthropogenic pollution on the rainwater chemistry in this area.

HUmic-LIke Substances (HULIS) comprise a significant fraction of the water-soluble organic aerosol mass and influence the water uptake properties of aerosols in the atmosphere. In this work, the abundance and size distributions of HULIS in ambient aerosols were measured in a rural location in South China at a time with a visible presence of crop residue burning. PM 2.5 samples of fresh smoke from burning rice straw and sugar cane leaves were also collected and analyzed for HULIS and major aerosol constituents. HULIS were abundant in both ambient samples and in fresh biomass burning emissions, accounting for ∼60% of the water-soluble organic carbon in the ambient aerosols and ∼30% in the fresh biomass burning aerosols. In the particles in the range of 0.32–1.8 μm, the abundance of HULIS was 40–90% of the combined abundance of sulfate and ammonium, suggesting that HULIS should be considered when quantifying the role of sulfate aerosols serving as cloud condensation nuclei. The size distribution of HULIS was characterized by a dominant droplet mode with a mass median aerodynamic diameter (MMAD) in the range of 0.63–0.87 μm, accounting for 81% of the total HULIS mass, a minor condensation mode (12%, MMAD: 0.23–0.28 μm) and a coarse mode (7%, MMAD: 4.0–5.7 μm). The small amount of HULIS in the coarse mode indicated that soil-derived HULIS was a very minor source. On the basis of the size distribution characteristics, HULIS were postulated to have multiple sources, including secondary formation in cloud droplets, secondary formation through heterogeneous reactions or aerosol-phase reactions, and primary emissions from biomass burning.

This study was designed to test the hypothesis that a 28-day tail suspension (SUS) could induce hypertrophy and enhanced myogenic and vasoconstrictor reactivity in middle cerebral arteries (MCAs), whereas atrophy and decreased myogenic and vasoconstrictor responses in mesenteric third-order arterioles (MSAs). Also, in addition to the functional enhancement in MCAs, structural changes in both kinds of arteries and functional decrement in MSAs could all be prevented by the intervention of daily 1-h dorsoventral (−Gx) gravitation by restoring to standing posture. To test this hypothesis, vessel diameters to pressure alterations and nonreceptor- and receptor-mediated agonists were determined using a pressure arteriograph with a procedure to measure in vivo length and decrease hysteresis of vessel segments and longitudinal middlemost sections of vessels fixed at maximally dilated state were examined using electron microscopy and histomorphometry. Functional studies showed that 28-day tail-suspended, head-down tilt (SUS) resulted in enhanced and decreased myogenic tone and vasoconstrictor responses, respectively, in MCAs and MSAs. Histomorphometric data revealed that SUS-induced hypertrophic changes in MCAs characterized by increases in thickness (T) and cross-sectional area (CSA) of the media and the number of vascular smooth-muscle-cell layers (NCL), whereas in MSAs, it induced decreases in medial CSA and T and NCL. Daily 1-h −Gx over 28 days can fully prevent these differential structural changes in both kinds of small arteries and the functional decrement in MSAs, but not the augmented myogenic tone and increased vasoreactivity in the MCAs. These findings have revealed special features of small resistance arteries during adaptation to microgravity with and without gravity-based countermeasure.