[Radiography study on osteotome sinus floor elevation with placed implant simultaneously with no graft augmentation].

OBJECTIVE: To investigate the change of endo-sinus bone height and bone volume in osteotome sinus floor elevation (OSFE) without bone graft but placing implants simultaneously by using cone beam computed tomography (CBCT) and three dimensional analysis, and to find the impacting factors on endo-sinus bone augmentation. METHODS: OSFE was performed in 38 edentulous patients with missing teeth at posterior maxillary region, and 44 implants were placed and referred for OSFE using no graft materials. CBCT was performed pre-surgery and 9－68 months post-surgery when the patients encountered another implant surgery. The gained bone height at mesial, distal, buccal and palatal sites around the implant in sinus were measured, volumetric measurements of the endo-sinus gained bone volume (ESGBV) in the elevated region were calculated by Mimics software. Univariate analysis and multiple linear regression were performed to investigate the impacting factors on the gained bone height and ESGBV. Marginal bone loss was recorded according to the periapical radiography after implant restoration. RESULTS: The mean residual bone height (RBH) pre-surgery was (3.41±1.23) mm, the mean protruded length (PL) into sinus of implant post-surgery was (3.41±1.28) mm, the mean endo-sinus gained bone height was (2.44±1.23) mm at distal sites, (2.88±1.20) mm at mesial sites, (2.83±1.22) mm at buccal sites and (2.96±1.16) mm at palatal sites, the mean endo-sinus gained bone height at distal sites was significantly lower than the other three sites (P < 0.05). The average endo-sinus gained bone height was (2.78±1.13) mm. The mean ESGBV was (122.15± 73.27) mm3. Univariate analysis showed the more RBH, the less bone height gained in sinus, which existed at buccal, lingual, mesial and distal sites (P < 0.001), and the more RBH, the smaller ESGBV gained (P=0.012). The ESGBV was significantly higher in the subjects whose bone generation period was more than 24 months than those whose bone generation period less than 24 months (P=0.034). The more PL, the more bone height and ESGBV gained (P=0.008). Multivariate analysis showed after adjusting factors of gender, age, smoking, width of sinus floor, thickness of sinus membrane pre-surgery, diameter and length of the implant, PL and bone generation period was positively correlated with mean endo-sinus gained bone height and ESGBV, while RBH negatively correlated with mean endo-sinus gained bone height. During the follow-up, the mean marginal bone loss was 0 (0－1.41) mm and all the implants loaded successfully. CONCLUSION: OSFE without bone graft but with placed implant simultaneously can increase endo-sinus gained bone height and ESGBV. RBH, PL and bone generation period are the significant factors impacting endo-sinus bone augmentation.

Variations in submicron aerosol liquid water content and the contribution of chemical components during heavy aerosol pollution episodes in winter in Beijing.

The aerosol liquid water content (ALWC) of submicron particles (PM1) was calculated in this work by three methods based on the aerosol physical and chemical properties measurement campaigns in winter in Beijing, including (a) the PM1 volume difference between the ambient and dry states by applying the particle number size distribution and particle hygroscopicity measurement; (b) the thermodynamic equilibrium model (ISORROPIA II) based on the chemical composition; and (c) the κ-Köhler theory of chemical composition with a volume mixing scheme. The three methods agreed well with reasonable uncertainties. The ALWC showed an exponential trend depending on the relative humidity (RH), and an abundant ALWC was also favored by the high PM1 mass loading. The contribution of different chemical component to the ALWC was evaluated by the κ-Köhler method, which revealed that during the measurement, the inorganics and organics could contribute to ~80% and ~20%, respectively, under ambient RH conditions, with the largest contributor of ammonium nitrate. When the RH was above 85%, the mass concentration of ALWC was comparable to, or even larger than, that of the dry PM1.

[Progress of long non-coding RNA in regulating cell autophagy in cancer].

The initiation of tumor is a complex process with multi-factor participation, particularly the activation of oncogenes and/or inactivation of tumor suppressor genes. Long non-coding RNAs (lncRNAs) play important roles in tumorigenesis. Additionally, as a metabolic process in cells, autophagy also contributes greatly to differentiation, metastasis and chemoresistance of tumor cells, and has become a central topic in recent years. The understanding of connection between lncRNAs and autophagy as well as their mechanisms underlying tumorigenesis, can provide new ideas for the diagnosis and treatment of tumors.

Author Correction: Prediction of size-resolved number concentration of cloud condensation nuclei and long-term measurements of their activation characteristics.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

The clinical features in Chinese patients with PRNP D178N mutation.

BACKGROUND AND PURPOSE: Fatal familial insomnia (FFI) is an autosomal dominant disease due to the D178N mutation of PRNP gene coupling with homozygous methionine (Met) at codon 129. It is generally considered that D178N mutation cases with 129 M/M homozygotes present as FFI, and 129 V/V as genetic CJD. However, the frequency of 129 Met alleles in Chinese population is much higher than that in Caucasians. This study aims to investigate the clinical features and genetic characteristics of Chinese D178N mutants in this genetic context. METHODS: We reviewed the clinical and genetic features of seven D178N patients. The clinical data, genetic data, electroencephalogram (EEG), brain magnetic resonance imaging (MRI), polysomnography (PSG), CSF 14-3-3 protein examinations of the seven patients were analyzed. RESULTS: The genotypes at codon 129 were all M/M. Four of the seven cases reported positive family history. Four patients were more likely the CJD phenotype and three were FFI phenotype according to the core clinical features. No major differences were found on the EEG, CSF 14-3-3 protein, and PSG presentations between this study and western studies. Novel neuroimaging findings were two patients had typical neuroimaging abnormalities of CJD and frontotemporal dementia, respectively. CONCLUSIONS: Unlike the western populations, the diverse phenotypical presentations of D178N mutants were not simply determined by the 129 genotypes in Chinese. The underlying modifying factors for phenotypical variations warrant further investigations. For those with atypical clinical and imaging features, genetic testing was important for final diagnosis.

Neutrophil CD16b crosslinking induces lipid raft-mediated activation of SHP-2 and affects cytokine expression and retarded neutrophil apoptosis.

Two different types of FcRs for IgG are constitutively expressed on the surface of human neutrophils, namely, FcγRIIA (CD32a) and FcγRIIIB (CD16b). Unlike FcγRIIA, FcγRIIIb is GPI anchored to the cell membrane and its signal transduction is still ambiguous. To further understand the signal transduction of CD16b, we compared neutrophil cytokine expression and apoptosis by the cross-linking of CD32a and CD16b respectively. We found that both CD32a and CD16b crosslinking can activate neutrophils, but did not exactly share cytokine expression profiles. On the other hand, CD16b cross-linking retarded neutrophil apoptosis while CD32a promoted it. By interrupting the lipid raft with methyl-ß-cyclodextrin (MßCD) and inhibiting the ITAM-SYK pathway with an SYK inhibitor (piceatannol), we found reduced apoptosis was at least partially mediated by lipid raft structure, but not the ITAM-SYK pathway. Additionally, CD16b but not CD32a cross-linking triggered SHP-2 phosphorylation and led to its translocation into lipid rafts. SHP-2 phosphorylation and translocation were inhibited by MßCD. Moreover, pre-inhibition of SHP-2 by a specific inhibitor (SHP099) converted IL-10 and SOCS3 expression level and promoted neutrophil apoptosis after CD16b crosslinking. In conclusion, these results, for the first time, collectively indicate that SHP-2 is activated by CD16b crosslinking in neutrophils and functions as a component of the raft-mediated signaling pathway.

[A study of the correlation between low back pain and occupational stress in coal miners].

Objective: To study the correlation between low back pain (LBP) and occupational stress in coal miners. Methods: From January 2015 to December 2016, a total of 472 front-line workers in a mining area of a large-scale coal mining enterprise in Shanxi, China were enrolled in the study. The general information, condition of LBP, and occupational stress level of the subjects were obtained by questionnaire survey. Dichotomous logistic regression (DLR) was used to analyze the correlation between LBP and occupational stress. Results: Of the 472 subjects, 186 subjects experienced LBP in the past year; the prevalence rate of LBP was 39.41%. The scores of the Occupational Role Questionnaire were significantly higher for workers in the LBP group than in the non-LBP group (P<0.01) . As revealed by the DLR analysis, age, marital status, length of service, occupational stress role, labor intensity, keeping single posture during work, and working in shifts were risk factors of LBP (P<0.01) , while smoking may be a protective factor against LBP (P<0.01) . Conclusion: Occupational stress role is a potential risk factor for LBP in coal miners (P<0.01) . Reasonable work assignment and timely alleviation of occupational stress may be one of the effective approaches to prevent LBP.

[Value of the concentration and integrity of serum cell-free DNA for the clinical diagnosis of esophageal carcinoma].

Objective: To explore the diagnostic value of serum cell-free DNA (cfDNA) concentration and integrity for esophageal carcinoma. Methods: Venous blood samples from 68 patients with esophageal cancer, 36 patients with benign esophageal lesions and 45 healthy subjects were collected. Circulating cfDNA was verified through quantitative real-time PCR (Alu-qPCR) using Alu-115 and Alu-247 primers. DNA integrity index was calculated as the ratio of Alu-qPCR results (Alu247/115). Concentrations of carcino-embryonic antigen (CEA) and squamous cell carcinoma associated antigen (SCC) were detected by chemiluminescence analyzer assay. Statistical analysis was performed using Mann-Whitney U test, Kruskal-Wallis H test and Spearman correlation test. The Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficiency of each index to esophageal carcinoma. Results: The median absolute serum Alu115 and the Alu247/115 index (1 162.0 ng/ml, 0.57) in esophageal cancer group were significantly higher than those in benign esophageal disease group (496.7 ng/ml, 0.43) and in healthy control group (432.3 ng/ml, 0.42) (all P<0.01, respectively). The Alu115 and Alu247/115 index of serum DNA in benign esophageal disease group were no statistically different from those in the healthy control group (all P>0.05, respectively). The levels of cfDNA and its integrity were not significantly correlated with age, gender, tumor differentiation, or disease stage according to American Joint Committee on Cancer (AJCC) staging system in the esophageal cancer group (all P>0.05). The serum Alu247/115 index of Stage Ⅲ patients was higher than that of Stage Ⅰ~Ⅱ patients(P<0.05). The serum Alu247/115 index of Stage Ⅳ was higher than that of Stage Ⅲ(P<0.05). In the esophageal cancer group, both of serum Alu115 and Alu247/115 index had no correlation with CEA or SCC (all P>0.05). The area under the ROC curve (AUC) of Alu115 and Alu247/115 index were 0.867 and 0.854, respectively, which were both higher than that of CEA (0.622) and SCC (0.753). The addition of Alu115 or Alu247/115 index to CEA and SCC detection increased the sensitivity of the diagnosis of esophageal cancer by 95.6% and 94.1%, respectively. Conclusions: The detection of serum cfDNA concentration and integrity is helpful to the early diagnosis and monitoring of esophageal cancer. Their diagnostic value of esophageal cancer is better than that of the traditional tumor markers CEA and SCC.

Prediction of size-resolved number concentration of cloud condensation nuclei and long-term measurements of their activation characteristics.

Atmospheric aerosol particles acting as cloud condensation nuclei (CCN) are key elements in the hydrological cycle and climate. To improve our understanding of the activation characteristics of CCN and to obtain accurate predictions of their concentrations, a long-term field campaign was carried out in the Yangtze River Delta, China. The results indicated that the CCN were easier to activate in this relatively polluted rural station than in clean (e.g., the Amazon region) or dusty (e.g., Kanpur-spring) locations, but were harder to activate than in more polluted urban areas (e.g., Beijing). An improved method, using two additional parameters-the maximum activation fraction and the degree of heterogeneity, is proposed to predict the accurate, size-resolved concentration of CCN. The value ranges and prediction uncertainties of these parameters were evaluated. The CCN predicted using this improved method with size-resolved chemical compositions under an assumption that all particles were internally mixed showed the best agreement with the long-term field measurements.

[Infection status, clinical symptoms and gene type transition of group A rotavirus in children, less than five years-of-age, with diarrhea in sentinel hospitals of Henan Province, China].

Objective: To investigate the infectious status, gene type transition and epidemiological features of rotavirus A isolated from infants and children (<59 months-of-age) in sentinel hospitals from 2008 to 2015 in Henan province, China. Methods: In total, 2 541 stool samples (each 3- 5 ml) were collected from infants and children aged less than five years in two sentinel hospitals and group A rotavirus was detected by a double antibody sandwich ELISA. Viral RNA was extracted from positive samples and G/P gene typing was performed using a two-step nested multiplex RT-PCR. Epidemiological information (including demographic information such as age, sex and clinical symptoms) was also collected from the patients and analyzed. Results: Group A rotavirus was detected in 30.9% (785/2 541) of diarrhea samples from children. The detection rate was higher in October (54.8%, 345/629) and lower in July (5%, 5/101) each year from 2008 to 2015. The group A rotavirus infection rate was higher in boys (30.6%, 451/1 476) than in girls (31.4%, 334/1 065) (χ2=0.18, P=0.664). Infection mainly occurred in 4-12 months old patients (61.3%, 481/785) (χ2=196.69, P<0.001), and the infection rate was lower in cities (26%, 258/992) compared with rural areas (34.0%, 527/1 549) (χ2=18.19, P<0.001). G typing of 785 strains of group A rotavirus revealed the following types: G1 (13.5%, 106 strains), G2 (11.1%, 87 strains), G3 (29.7%, 233 strains), and G9 (57.5%, 451 strains); P typing revealed the predominance of P[4] (11.3%, 89 strains) and P[8] (84.7%, 665 strains); gene type combinations comprised mainly G9P[8], G2P[4], G3P[8], G1P[8], respectively accounted for 52.9% (415), 9.7% (76), 17.3% (136), 11.3% (89). Gene type combinations G1 [8] and G3P[8] have been decreasing in prevalence since 2008 and G9P[8] has become the dominant gene type of group A rotavirus in Henan province. Among the group A rotavirus infection samples, the male:female infection ratio was 1.4∶1 (451/334), with no significant difference in the infection rate (χ2=0.18, P=0.664); the infection rate was higher in 4- 12 months old patients (61.3%, 481/785), with a significant difference detected between age groups (χ2=196.69, P<0.001). The rate of detection was lower in cities (26.0%, 258/992) than in rural areas (34.0%, 527/1 549) (χ2=18.19, P<0.001). Clinical analysis revealed a body temperature of below 37 degrees in 75.7% of positive cases (594 patients), 37.0- 37.5 degrees in 17.2% of cases (135 patients), 37.6-38.0 degrees in 2.0% of cases (16 patients), and above 38 degrees in 5.1% of cases (40 patients), with most cases showing no fever or a mild fever. The frequency of episodes of diarrhea among the patients was 0- 3 times (21.1%, 166 cases), 4- 6 times (65.6%, 515 cases), 7- 9 times (8.0%, 63 cases), or 10- 15 times (5.2%, 41 cases), mainly showing mild and moderate diarrhea. Vomiting also varied in frequency among the patients from no vomiting (86.9%, 682 cases), 1-2 times (11.8%, 92 cases), 3 times (6.0%, 47 cases), and more than 3 times (0.4%, 3 cases). The occurrence of dehydration varied from no dehydration (86.9%, 682 cases), mild dehydration of 1%- 5% (12.1%, 95 cases), to severe dehydration of ≥5% (1.0%, 8 cases). Conclusion: A higher infection rate of group A rotavirus was detected in children younger than five years of age with acute diarrhea in sentinel hospitals in Henan province, including part-mixed infection cases. A predominance of cases was detected in the autumn, and secondly the spring of each year. Gene type G9P[8] was most frequently isolated. The majority of patients displayed no fever, vomiting or dehydration. The cases with clinical symptoms of fever, diarrhea, vomiting and dehydration often showed mild disease.

[A bibliometric analysis of literature on hand-transmitted vibration in China, 1990-2016].

Objective: To investigate the features of literature on hand-transmitted vibration in China, 1990-2016. Methods: In September 2017, the studies on hand-transmitted vibration in China, which were published in Chinese or English during 1990-2016, with "China" and "Taiwan" as the places where author affiliations were located, were retrieved. A bibliometric analysis was performed to investigate the type of articles, publication time, the journals in which articles were published, author affiliations, author regions, and funding. Results: A total of 205 articles on hand-transmitted vibration were retrieved. There were 7.59 articles on average published annually from 1990 to 2016. In the 205 articles, 114 (55.61%) were published in the journals indexed in one or two core journal databases. In the 64 journals, 22 (34.38%) were indexed in one or two core journal databases. The first authors were from 22 provincial regions (provinces, autonomous regions, or centrally administered municipalities) in China, with 152 articles (74.15%) by the authors in the top five regions. There were a total of 876 authors, and the co-authorship degree was 4.27 (876/205). Most of the first authors (136 articles, 66.34%) were affiliated with universities or institutes for prevention and control of occupational diseases. Among the 205 articles, 103 (50.24%) were original articles or investigations, and 72 (35.12%) were funded. Conclusion: The studies on hand-transmitted vibration fluctuated and increased from 1990 to 2016, with a relatively concentrated distribution in terms of sources, regions, and institutions. Interregional and international academic exchange should be strengthened.

[miR-202 contributes to sensitizing MM cells to drug significantly via activing JNK/SAPK signaling pathway].

Objective: To explore the role of miR-202 in multiple myeloma (MM) cells, and study the regulation of miR-202 on drug sensitivity of MM cells. Methods: miR-202 and BAFF mRNA levels were detected by real-time PCR. U266 cells were transfected with miR-202-mimics, miR-202-inhibitor, siBAFF and their negative controls. After above treatments, protein levels of Bcl-2 family and MAPK signaling pathway were detected by Western blot analysis, and the proliferation and apoptosis ability of MM cells were examined by WST-1, Annexin V-FLUOS assay, respectively. Results: The results showed that the expression of miR-202 in CD138+ MM cells (0.304±0.354) and U266 cells (0.052± 0.009) were lower than in normal controls (3.550 ± 1.126) (P<0.001, P=0.009), whereas BAFF mRNA levels (5.700 ± 0.734, 9.576 ± 2.887) were higher than in normal controls (1.819 ± 0.853) (P<0.001, P= 0.006). The proliferation ability of U266 cells transfected with miR-202 mimics was significantly inhibited than in control group [(56.04±0.021)% vs (18.89±0.32)%, P=0.002]. The result of Western blot showed that the expression of Bcl-2 decreased by about 24%, and the expression of Bax increased by about 124% in cells transfected with miR-202 mimics. The apoptosis rate in cells transfected with miR-202 mimics was significantly more than in control group [(49.60±4.89)% vs (26.20±1.28)%, P=0.029]. The apoptosis rate in miR-202 mimics combined with Bort group (51.23±5.41)% was higher as compared with Bort treatment alone (31.70±4.40)% or miR-202 mimics control combined with Bort group (27.94±4.04)%, (P=0.047, P= 0.028), whereas the apoptosis rate in miR-202 mimics combined with Thal or Dex had no significant difference compared with miR-202 mimics control [(11.66±1.91)% vs (10.63±1.74)%, P=0.700; (16.35± 1.32)% vs (17.43 ± 1.95)%, P=0.400]. The inhibitory rate of cell growth in miR-202 mimics combined with Bort group was higher as compared with Bort treatment alone [(36.93±5.98)% vs (18.18±4.10)%, P= 0.029]. The expressions of p-JNK protein decreased in U266 cells transfected with miR-202 mimics and treated with Bort. Conclusion: miR-202 mimics combined with Bort could inhibit proliferation and induce apoptosis of U266 cells through negative regulating target gene BAFF, which further inhibited the JNK/SAPK signaling pathway.

[Expression and significance of serum microRNA-135a-5p level in colorectal cancer].

Objective: To explore the expression level of serum miR135a-5p and its diagnostic value in colorectal cancer (CRC). Methods: Serum samples were randomly collected from 60 primary CRC patients, 40 patients with intestinal polyps and 50 healthy controls, and the serum concentrations of miR135a-5p, CEA and CA199 were detected. The relationships between serum miR135a-5p level and clinicopathological parameters were analyzed by Mann-Whitney U test. The correlation of serum miR135a-5p level and serum concentrations of CEA or CA199 was analyzed by Pearson's correlation test.Receiver operating characteristic (ROC) curves and area under the curve (AUC) were used to evaluate the diagnostic efficacy of miR135a-5p, CEA and CA199 as diagnostic indicators. Results: The serum level of miR135a-5p in CRC patient was 2.451 (1.107, 4.413), significantly higher than 0.946 (0.401, 1.942) in the patients with intestinal polyps and 0.949 (0.194, 1.415) in the healthy controls (U = 351.0 and U = 313.0, respectively, P<0.001). The serum level of miR135a-5p in CRC patients was associated with both histological differentiation and clinical stage (P<0.05 for both), however, not correlated with the serum concentration of CEA (r2 = 0.023, P = 0.293) or CA199 (r2 = 0.067, P = 0.068). The AUC of serum miR135a-5p level in CRC patients was 0.832 (0.730-0.930) when compared to the patients with intestinal polyps and was 0.875 (0.800-0.950) when compared with the healthy controls. Conclusions: The serum level of miR135a-5p in CRC patients is significantly higher than that in patients with intestinal polyps and healthy controls, and might be an important diagnostic marker of CRC.

[Surveillance for viral diarrhea in sentinel hospitals in Henan province, 2013-2015].

Objective: To investigate the infection status of human rotavirus, calicivirus, astrovirus and enteric adenovirus in children aged <5 years in disease surveillance areas in Henan province from 2013 to 2015. Methods: A total of 880 stool samples were collected from four sentinel hospitals and group A rotavirus was detected by ELISA and group A rotavirus G/P genotyping was performed with nested multiplex RT-PCR, while rotavirus (group B, C), calicivirus and astrovirus were detected by two-step multiplex RT-PCR and adenovirus were detected by PCR. The epidemiological data of positive cases were statistically analyzed. Results: A total of 594 positive samples were detected, including 24 mixed infection samples, 370 rotavirus positive samples (42.0%); 162 calicivirus positive samples (18.4%); 69 astrovirus positive samples (7.8%) and 17 enteric adenovirus positive samples (1.9%). The overall positive rate of four viruses was significantly higher in urban area than in rural area, but the positive rate of rotavirus was higher in males than in females and in younger age group than in older age group. G9P [8] was the major genotype of group A rotavirus, there were two seasonal infection peaks in autumn and spring. Norovirus Ⅱ was the predominant type of calicivirus and the infection peak was in spring. Viral diarrhea cases were distributed in different age groups, mainly in age groups 0-12 months (rotavirus) and 3-5 years (calicivirus). The main clinical symptoms included fever, diarrhea and vomiting. The etiological characteristics differed with gender and area. Conclusions: The infection rate of diarrheal viruses was higher in young children <5 years old in disease surveillance areas. The epidemiological and clinical features varied with the type of pathogen.

The influence of emission control on particle number size distribution and new particle formation during China's V-Day parade in 2015.

Temporary strict emission control strategies were conducted to ensure good air quality for China's V-Day parade (August 20-September 3, 2015) in Beijing and nearby cities. The influence of the emission control on particle number size distribution (PNSD) was evaluated based on the long-term measurements of PNSD at a rural site (Shangdianzi) located northeast of Beijing. This study also presented the comparison results of PNSD during the parade in 2015 and the Olympics in 2008 (August 8-23), as well as the same period without strict emission control in 2010-2013 (August 20-September 3). Compared with the same period in 2010-2013 and 2008 Olympics, the accumulation mode particle number concentration showed a significant reduction in 2015, and the PM1 mass concentration decreased by approximately 60-90%. The alleviation of the PM1 was also associated with the weather conditions. The back trajectories analysis results showed that the southerly air mass passing through the polluted areas accounted for 14% of the total back trajectories in 2015, which contributed to approximately 60% in the other years. During the control period in 2015, there were six new particle formation (NPF) events observed, with a higher frequency, but a lower formation rate and growth rate than the same period in 2010-2013. The comparison of the condensation sink (CS), sulfuric acid, solar radiation and relative humidity among the different years indicated that at Shangdianzi station, the first factor in determining the NPF occurrence was the CS, and the second factor could be the concentration level of precursor vapors participating in the NPF event (e.g., sulfuric acid).

Characterization and parameterization of aerosol cloud condensation nuclei activation under different pollution conditions.

To better understand the cloud condensation nuclei (CCN) activation capacity of aerosol particles in different pollution conditions, a long-term field experiment was carried out at a regional GAW (Global Atmosphere Watch) station in the Yangtze River Delta area of China. The homogeneity of aerosol particles was the highest in clean weather, with the highest active fraction of all the weather types. For pollution with the same visibility, the residual aerosol particles in higher relative humidity weather conditions were more externally mixed and heterogeneous, with a lower hygroscopic capacity. The hygroscopic capacity (κ) of organic aerosols can be classified into 0.1 and 0.2 in different weather types. The particles at ~150 nm were easily activated in haze weather conditions. For CCN predictions, the bulk chemical composition method was closer to observations at low supersaturations (≤0.1%), whereas when the supersaturation was ≥0.2%, the size-resolved chemical composition method was more accurate. As for the mixing state of the aerosol particles, in haze, heavy haze, and severe haze weather conditions CCN predictions based on the internal mixing assumption were robust, whereas for other weather conditions, predictions based on the external mixing assumption were more accurate.

Effect of wilfortrine on human hepatic cancer HepG2 cell proliferation potential in vitro.

Liver cancers are characterized by high morbidity and mortality owing to few effective drugs for its treatment. Wilfortrine has several pharmacological effects, including an inhibitory effect on liver cancer cell proliferation. However, whether wilfortrine can induce liver cancer cell apoptosis has not been elucidated. We investigated the role of wilfortrine on liver cancer cell HepG2 apoptosis and analyzed its possible mechanisms to provide a theoretical basis for clinical analysis of liver cancer pathogenesis. The liver cancer cell line HepG2 was treated with 40 mM wilfortrine for 48 h. Flow cytometry was applied to detect HepG2 cell apoptosis and cell cycle changes. Western blot was used to analyze Bcl-2 and Bax expression. The HepG2 cell apoptosis rate increased significantly after treatment with wilfortrine, especially the early apoptosis rate (P < 0.05). However, wilfortrine did not change the cell cycle of HepG2 cells. After wilfortrine treatment, Bcl- 2 expression decreased significantly (P < 0.05); on the contrary, Bax expression increased noticeably compared with the control group (P < 0.05). Wilfortrine can induce liver cancer cell HepG2 apoptosis, but with no effect on the cell cycle, mainly by promoting Bax expression and inhibiting anti-apoptotic protein Bcl-2 expression.

Significant concentration changes of chemical components of PM1 in the Yangtze River Delta area of China and the implications for the formation mechanism of heavy haze-fog pollution.

Since the winter season of 2013, a number of persistent haze-fog events have occurred in central-eastern China. Continuous measurements of the chemical and physical properties of PM1 at a regional background station in the Yangtze River Delta area of China from 16 Nov. to 18 Dec., 2013 revealed several haze-fog events, among which a heavy haze-fog event occurred between 6 Dec. and 8 Dec. The mean concentration of PM1 was 212µgm(-3) in the heavy haze-fog period, which was about 10 times higher than on clean days and featured a peak mass concentration that reached 298µgm(-3). Organics were the largest contributor to the dramatic rise of PM1 on heavy haze-fog days (average mass concentration of 86µgm(-3)), followed by nitrate (58µgm(-3)), sulfate (35µgm(-3)), ammonium (29µgm(-3)), and chloride (4.0µgm(-3)). Nitrate exhibited the largest increase (~20 factors), associated with a significant increase in NOx. This was mainly attributable to increased coal combustion emissions, relative to motor vehicle emissions, and was caused by short-distance pollutant transport within surrounding areas. Low-volatility oxidized organic aerosols (OA) (LV-OOA) and biomass-burning OA (BBOA) also increased sharply on heavy haze-fog days, exhibiting an enhanced oxidation capacity of the atmosphere and increased emissions from biomass burning. The strengthening of the oxidation capacity during the heavy pollution episode, along with lower solar radiation, was probably due to increased biomass burning, which were important precursors of O3. The prevailing meteorological conditions, including low wind and high relative humidity, and short distance transported gaseous and particulate matter surrounding of the sampling site, coincided with the increased pollutant concentrations mainly from biomass-burning mentioned above to cause the persistent haze-fog event in the YRD area.