[Characteristics and diagnostic value of serum bile acids profile in pregnant women with intrahepatic cholestasis of pregnancy and asymptomatic hypercholanemia of pregnancy]

Objective: To analyze serum bile acid profiles in pregnant women with normal pregnancy, intrahepatic cholestasis of pregnancy (ICP) and asymptomatic hypercholanemia of pregnancy (AHP), and to evaluate the application value of serum bile acid profiles in the diagnosis of ICP and AHP. Methods: The clinical data of 122 pregnant women who underwent prenatal examination in Xuzhou Maternal and Child Health Care Hospital from June 2022 to May 2023 were collected, including 54 cases of normal pregnancy group, 28 cases of ICP group and 40 cases of AHP group. Ultraperformance liquid chromatography-tandem mass spectrometry was used to measure the levels of 15 serum bile acids in each group, including cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), lithocholic acid (LCA), ursodeoxycholic acid (UDCA), glycolcholic acid (GCA), glycochenodeoxycholic acid (GCDCA), glycodeoxycholic acid (GDCA), glycolithocholic acid (GLCA), glycoursodeoxycholic acid (GUDCA), taurocholic acid (TCA), taurochenodeoxycholic acid (TCDCA), taurodeoxycholic acid (TDCA), taurolithocholic acid (TLCA) and tauroursodeoxycholic acid (TUDCA). Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to screen differential bile acids. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficacy of differential bile acids and combined indicators between groups. Results: (1) Compared with normal pregnancy group, the serum levels of LCA, GCA, GCDCA, GDCA, GLCA, UDCA, TCA, TCDCA, TDCA, TLCA, GUDCA and TUDCA in ICP group were significantly different (all P<0.05), while the levels of LCA, DCA, GCA, GCDCA, GDCA, GLCA, TCA, TCDCA, TDCA, TLCA, GUDCA and TUDCA in AHP group were significantly different (all P<0.05). Compared with ICP group, the serum levels of CDCA, DCA, UDCA, TDCA, GUDCA and TUDCA in AHP group were significantly different (all P<0.05). (2) In the OPLS-DA model, the differential bile acids between ICP group and AHP group were TUDCA, TCA, UDCA, GUDCA and GCA, and their variable importance in projection (VIP) were 1.489, 1.345, 1.344, 1.184 and 1.111, respectively. TCA, GCDCA, GCA, TDCA, GDCA and TCDCA were the differentially expressed bile acids between AHP group and normal pregnancy group, and their VIP values were 1.236, 1.229, 1.197, 1.145, 1.139 and 1.138, respectively. (3) ROC analysis showed that the area under the curve (AUC) of TUDCA, TCA, UDCA, GUDCA and GCA in the differential diagnosis of ICP and AHP was 0.860, and the sensitivity and specificity were 67.9% and 95.0%, respectively. The AUC of TCA, GCDCA, GCA, TDCA, GDCA and TCDCA in the diagnosis of AHP was 0.964, and the sensitivity and specificity were 95.0% and 93.1%, respectively. Conclusions: There are differences in serum bile acid profiles among normal pregnant women, ICP and AHP. The serum bile acid profiles of pregnant women have potential application value in the differential diagnosis of ICP and AHP and the diagnosis of AHP.

[Preparation of a dual-specific antibody targeting human CD123 and exploration of its anti-acute myeloid leukemia effects]

Objective: To construct a novel dual-specific antibody targeting human CD123 (CD123 DuAb) and study its effects in acute myeloid leukemia (AML) . Methods: Based on the variable region of the CD123 monoclonal antibody independently developed at our institution, the CD123 DuAb expression plasmid was constructed by molecular cloning and transfected into ExpiCHO-S cells to prepare the antibody protein. Through a series of in vitro experiments, its activation and proliferation effect on T cells, as well as the effect of promoting T-cell killing of AML cells, were verified. Results: ① A novel CD123 DuAb plasmid targeting CD123 was successfully constructed and expressed in the Expi-CHO eukaryotic system. ②The CD123 DuAb could bind both CD3 on T cells and CD123 on CD123(+) tumor cells. ③When T cells were co-cultured with MV4-11 cells with addition of the CD123 DuAb at a concentration of 1 nmol/L, the positive expression rates of CD69 and CD25 on T cells were 68.0% and 44.3%, respectively, which were significantly higher than those of the control group (P<0.05). ④Co-culture with CD123 DuAb at 1 nmol/L promoted T-cell proliferation, and the absolute T-cell count increased from 5×10(5)/ml to 3.2×10(6)/ml on day 9, and CFSE fluorescence intensity decreased significantly. ⑤ With the increase in CD123 DuAb concentration in the culture system, T-cell exhaustion and apoptosis increased. When the CD123 DuAb was added at a concentration of 1 nmol/L to the culture system, the proportion of CD8(+) PD-1(+) LAG-3(+) T cells was 10.90%, and the proportion of propidium iodide (PI) (-) Annexin Ⅴ(+) T cells and PI(+) Annexin Ⅴ(+) T cells was 18.27% and 11.43%, respectively, which were significantly higher than those in the control group (P<0.05). ⑥ The CD123 DuAb significantly activated T cells, and the activation intensity was positively correlated with its concentration. The expression rate of CD107a on T cells reached 16.05% with 1 nmol/L CD123 DuAb, which was significantly higher than that of the control group (P<0.05). ⑦The CD123 DuAb promoted cytokine secretion by T cells at a concentration of 1 nmol/L, and the concentration of IFN-γ and TNF-α in the supernatant of the co-culture system reached 193.8 pg/ml and 169.8 pg/ml, respectively, which was significantly higher than that of the control group (P<0.05). ⑧When CD123 DuAb was added at a concentration of 1 nmol/L to the co-culture system of T cells and CD123(+) tumor cells, the killing intensity of T cells significantly increased, and the residual rates of CD123(+) MV4-11 cells, CD123(+) Molm13 cells, and CD123(+) THP-1 cells were 7.4%, 6.7%, and 14.6% on day 3, respectively, which were significantly lower than those in the control group (P<0.05) . Conclusion: In this study, a novel CD123 DuAb was constructed and expressed. In vitro experiments verified that the DuAb binds to CD123(+) tumor cells and T cells simultaneously, promotes T-cell activation and proliferation, and facilitates their anti-leukemia effect, which provides a basis for further clinical research.

[Research progress on global health competency and its models]

At present, the research on Global Health Competencies is mainly conducted in the field of the establishment of competency models and application of indicators. This review summarizes the research progress of the Global Health Competency and its models, and focuses on cutting-edge research from the aspects of target audience, purpose, content, classical model, methods and future development. The competency model is suggested to be adjusted and updated according to the practices of different countries and regions. The research and funding of the competency model in the field of public health is suggested to be strengthened, and the global health and diplomacy are suggested to be combined to enrich and improve the competency model. Finally, this review aims to promote Global Health Competencies research in China, especially to improve the global health talent training system and relevant policies in further research.

[The expression of Plakoglobin in residual cancer after neoadjuvant chemotherapy for breast cancer and its prognostic impact on patients]

Objective: To investigate the relationship between the expression levels of Plakoglobin protein in residual lesions after neoadjuvant chemotherapy (NAC) and the prognosis of breast cancer patients. Methods: Clinical and pathological data from 174 breast cancer patients who underwent surgery after receiving NAC at the Cancer Hospital of Chinese Academy of Medical Sciences from January 2009 to December 2017 were collected. The expression level of Plakoglobin in residual cancer lesions was evaluated by immunohistochemistry. The correlation between Plakoglobin expression level and clinicopathological features was analyzed. Survival analysis was performed using the Kaplan-Meier method, and Cox proportional hazard regression models were used for factor analysis. Results: Among the 174 patients, 140 had low expression of Plakoglobin, and 34 had high expression. The median disease-free survival (DFS) and overall survival (OS) in the Plakoglobin low expression group were 59.46 and 71.68 months, respectively, both of which were higher than those in the high expression group (36.58 and 47.26 months, respectively, both P<0.05). Univariate analysis showed that Plakoglobin expression, pathological N stage, lymphovascular invasion status, histological grade, Ki-67, and molecular subtypes were associated with OS (all P<0.05), while pathological N stage, histological grade, and Ki-67 were associated with DFS (all P<0.05). Multivariate analysis revealed that Plakoglobin expression (HR=2.438, 95% CI: 1.256-4.735, P=0.008) was an independent predictor for OS, and Ki-67 (HR=2.228, 95% CI: 1.316-3.773, P=0.003) was an independent predictor for DFS. Conclusion: In breast cancer patients with residual lesions after NAC, those with low Plakoglobin expression have relatively longer OS and Plakoglobin is an independent prognostic factor for OS.

[Applications of anterior segment optical coherence tomography in corneal refractive surgery]

Anterior segment optical coherence tomography (AS-OCT) has the characteristics of non-contact, noninvasive, high sensitivity, and repeatability, and offers high-resolution in vivo imaging of the structures of the anterior eye segment. It can be used in the diagnosis and assistance of conditions related to the anterior eye segment. This review provides an update on the research and clinical applications of AS-OCT in corneal refractive surgery, including preoperative keratoconus screening, intraoperative real-time visualization of corneal structures, postoperative corneal evaluation, and management of postoperative complications. We also explore the potential application of AS-OCT in combination with corneal biomechanical detection for corneal refractive surgery.

[Exploration of the classification of public health intervention and its implication for China]

Public health interventions refer to a series of organized and specific measures implemented in specific situations to achieve goals related to improving health, preventing and controlling diseases, and more. As research on intervention measures has deepened, the classification of public health interventions has gradually developed, clarifying the nature, categories and intervention targets of these measures. This typological study can help standardize the concepts of public health interventions, develop, select, and evaluate the effectiveness of intervention measures, and improve the effectiveness of public health actions. This paper reviews the main international classification models of intervention measures, analyzes and summarizes five classification methods of public health interventions, namely, based on goals, nature, objects, hierarchies, and modes of action, and introduces relevant cases. The paper proposes that China should conduct further in-depth and systematic research on public health interventions, develop evidence-based intervention measures and practices, promote the effective transformation of intervention measures and results, and facilitate the development of public health.

Copper isotope evidence for sulfide fractionation and lower crustal foundering in making continental crust

The continental crust is strongly depleted in copper compared with its building blocks-primary arc magmas-and this depletion is intrinsically associated with continental crust formation. However, the process by which Cu removal occurs remains enigmatic. Here we show, using Cu isotopes, that subduction-zone processes and mantle melting produce limited fractionation of Cu isotopes in arc magmas, and, instead, the heterogeneous Cu isotopic compositions of lower crustal rocks, which negatively correlate with Cu contents, suggest segregation or accumulation of isotopically light sulfides during intracrustal differentiation of arc magmas. This is supported by the extremely light Cu isotopic compositions of lower crustal mafic cumulates and heavy Cu isotopic compositions of differentiated magmas in thick continental arcs. Intracrustal differentiation of mantle-derived magmas and subsequent foundering of sulfide-rich mafic cumulates preferentially removes isotopically light Cu, leaving a Cu-depleted and isotopically heavy continental crust.

[Analysis of the incidence and burden of intraocular foreign bodies in China based on age-period-cohort model]

Objective: This study aims to analyze the incidence, disease burden, and trend of intraocular foreign bodies in China from 1990 to 2019, and to analyze the trend of changes in age, period, and cohort of Chinese men. Methods: The data related to the incidence rate and disease burden of intraocular foreign bodies in China from 1990 to 2019 were obtained from the Global Burden of Disease Database (GBD database) on the website of the Institute for Health Indicators and Evaluation (IHME) of the University of Washington, United States, and the annual percentage rate change (AAPC) of intraocular foreign bodies in China was calculated using the Joinpoint software to describe the long-term trend of their incidence rate and disease burden over time. Using Stata17 software, an age period cohort model was constructed to analyze the age, period, and cohort factors affecting intraocular foreign bodies in men. Results: In 2019, the incidence rate of intraocular foreign bodies in China was 791.20/100 000, and the DALY rate was 10.32/100 000, with an average annual decline rate of 1.70% and 1.48% respectively. In 2019, the number of cases of intraocular foreign bodies in China was 11.253 6 million, and the DALY was 1 812.29 million person years. Among them, the incidence and disease burden of intraocular foreign bodies in men were more severe than those in women, and the incidence and disease burden risk of intraocular foreign bodies in men aged 30-35 and 45-50 were the highest. The incidence and disease burden risk of intraocular foreign bodies in elderly men gradually increased. Conclusions: As a common ophthalmic disease, the incidence of intraocular foreign bodies and the DALY rate are declining, but the disease burden is increasing. With the aging of the population, the incidence of intraocular foreign bodies in the elderly will further increase in the future, which should be considered by policy makers. The findings of this study can help governments and healthcare planners formulate practical and targeted policy responses.

[Prognostic analysis of acute pulmonary thromboembolism with newly diagnosed atrial fibrillation]

Objective: To analyze the clinical characteristics and to explore the prognostic factors of acute pulmonary embolism(APE) with newly diagnosed atrial fibrillation(AF). Methods: The medical records of inpatients with APE discharged from Beijing Anzhen Hospital between January 1, 2008, and December 31, 2021 were retrospectively reviewed. The clinical symptoms, complications, laboratory results, echocardiographic parameters, simplified pulmonary embolism severity index (sPESI) and adverse in-hospital outcome were compared between the newly diagnosed AF group and the sinus rhythm group. Logistic regression analysis was used to evaluate the risk factors of adverse in-hospital outcome with APE. Results: Fifty-one patients were included in newly diagnosed AF group and 102 cases in the sinus rhythm group. The patients in newly diagnosed AF group had greater sPESI scores, higher proportion of sPESI≥2 scores, higher incidence of adverse in-hospital outcome as well as longer hospital stay days. Newly diagnosed AF and sPESI≥2 scores were independent predictors affecting adverse in-hospital outcome. The area under ROC curve in newly diagnosed AF combined with sPESI≥2 scores was largest. Conclusions: The APE patients with newly diagnosed AF were more severely ill and prone to in-hospital adverse outcome. Newly diagnosed AF was an independent predictor affecting adverse in-hospital outcome. sPESI≥2 combined with newly diagnosed AF scores had a high predictive value for the occurrence of in-hospital adverse outcome.

Extensive crystal fractionation of high-silica magmas revealed by K isotopes

Fractional crystallization plays a critical role in generating the differentiated continental crust on Earth. However, whether efficient crystal-melt separation can occur in viscous felsic magmas remains a long-standing debate because of the difficulty in discriminating between differentiated melts and complementary cumulates. Here, we found large (~1 per mil) potassium isotopic variation in 54 strongly peraluminous high-silica (silicon dioxide >70 weight %) leucogranites from the Himalayan orogen, with potassium isotopes correlated with trace elemental proxies (e.g., strontium, rubidium/strontium, and europium anomaly) for plagioclase crystallization. Quantitative modeling requires up to ~60 to 90% fractional crystallization to account for the progressively light potassium isotopic composition of the fractionated leucogranites, while plagioclase accumulation results in enrichment of heavy potassium isotopes in cumulate leucogranites. Our findings strongly support fractional crystallization of high-silica magmas and highlight the great potential of potassium isotopes in studying felsic magma differentiation.

[Analysis of clinical features and poor prognostic factors of acute hematogenous osteomyelitis in children]

Objective: To analyze the clinical characteristics, pathogenic bacteria, complications and risk factors of prognosis of acute hematogenous osteomyelitis in children. Methods: The clinical manifestations, laboratorg tests, etiological charateristics and clinical data of 107 patients with acute hematogenous osteomyelitis admitted to Beijing Children's Hospital from January 2017 to December 2020 were retrospectively analyzed. According to the drug sensitivity results of Staphylococcus aureus, the group was divided into methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible Staphylococcus aureus (MSSA) group; according to the presence or absence of complications, the group was divided into the group with and without complications; according to the prognosis of the follow-up children, the group was divided into good prognosis and poor prognosis. The χ² test or Mann-Whitney U test used for comparison between groups, and Logistic regression was used to analyze the risk factors for complications and prognosis. Results: Of the 107 patients, 62 were males and 45 were females. The age of presentation was 5.6 (1.7, 10.0) years, including 5 patients (4.7%) age from >28 days to 3 months, 46 patients (43.0%) age from >3 months to 5 years, 43 patients (40.2%)>5-12 years of age, and 13 patients (12.1%)>12-18 years of age. The first symptoms were acute fever in 35 patients (32.7%), limb pain in 24 patients (22.4%), and fever with limb pain in 23 patients (21.5%). Pathogen culture was positive in 75 patients (70.1%), Streptococcus pyogenes, Salmonella enterica and Escherichia coli in 1 case (1.4%) each, and Staphylococcus aureus in 72 cases (96.0%), among them, 47 cases were MSSA, 22 cases were MRSA, and 3 cases had positive reports of Staphylococcus aureus from other hospitals without drug-sensitive tests. The proportion of infected children living in rural areas and receiving surgical treatment was higher in the MRSA group than in the MSSA group (14 cases (63.6%) vs. 18 cases (38.3%) and 21 cases (95.5%) vs. 33 cases (70.2%), χ²=3.87, 4.23, both P<0.05). Sixty-five children had no complications while 42 children (39.3%) suffered from complications. Common complications consisted of 19 cases (17.8%) of sepsis, 17 cases (15.9%) of septic arthritis, and 12 cases (11.2%) of venous thrombosis. The group with complications showed higher mental changes, decreased appetite and (or) weakness, positive pathogenic cultures, and time from admission to surgery than the group without complications (18 cases (42.9%) vs. 9 cases (13.8%), 20 cases (47.6%) vs. 12 cases (18.5%), 34 cases (81.0%) vs. 41 cases (63.1%), 3.5 (2.0, 6.0) vs. 2.0 (1.0, 4.0) d,χ²=11.38, 10.35, 3.89, Z=2.21, all P<0.05). The poor prognosis group had more comorbidities, combined local complications, and positive aureus than the good prognosis group (10/15 vs. 34.9% (30/86), 7/15 vs. 17.4% (15/86), 14/15 vs. 61.6% (53/86), χ²=5.39, 6.40, 4.42, all P<0.05). Multifactorial Logistic regression analysis showed that acute phase C-reactive protein (CRP) was both an independent risk factor for complications (OR=1.01, 95%CI 1.01-1.02) and an independent risk factor for poor prognosis (OR=1.01, 95%CI 1.00-1.02). Conclusions: The first symptoms of acute hematogenous osteomyelitis are acute fever, limb pain, and fever with limb pain are most common. Staphylococcus aureus is the most common pathogenic organism. Those with loss of appetite and (or) weakness, mental changes, positive pathogenic cultures, and longer time between admission and surgery are prone to complications. Those with complications, combined local complications, and positive for Staphylococcus aureus had a poor prognosis. Elevated CRP is an independent risk factor not only for complications but for poor prognosis as well.

[Clinical characteristics and long-term follow-up results of radiofrequency ablation for the treatment of ventricular tachycardia in patients with arrhythmogenic left ventricular cardiomyopathy]

Objective: To investigate the acute and long-term outcome of catheter ablation for the treatment of ventricular tachycardia (VT) in patients with arrhythmogenic left ventricular cardiomyopathy (ALVC). Methods: This retrospective, cross-sectional study enrolled ALVC patients undergoing radiofrequency ablation for the treatment of VT at the First Affiliated Hospital of Nanjing Medical University from January 2011 to December 2018 and collected their clinical characteristics and intraoperative electrophysiological examination. Patients were followed up every 6 months after radiofrequency ablation until August 2021. Echocardiographic results and VT recurrence post radiofrequency ablation were analysed. Results: Totally 12 patients were enrolled (mean age: (42±15) years, 11 males(11/12)). The mean of left ventricular end diastolic diameter (LVDd) and left ventricular ejection fraction (LVEF) were (51±5)mm and (65±5)%, respectively. Twelve VTs were induced in 10 patients during the electrophysiological study, and the mean tachycardia cycle length was (293±65) ms. Three-dimensional substrate mapping revealed the diseased area at endocardial site in one patient, at epicardial sites in the other 11 patients (involved endocardial sites in 2 cases) with the basal part near the mitral annulus being the predilection for the substrate (10/11). After the catheter ablation at the endocardial and epicardial sites respectively, the complete procedure endpoint was achieved in all patients (VT cannot be induced post ablation). The median follow-up time was 65 (25, 123) months. One patient was lost to follow-up, and the other 11 patients survived without VT. No significant cardiac function deterioration was detected by the echocardiographic examination ((51±5)mm vs. (52±5)mm, P>0.05 for LVDd, (65±5)% vs. (60±6)%, P>0.05 for LVEF) at the end of follow-up. Conclusion: After radiofrequency ablation, the complete procedure endpoint is achieved in ALVC patients, and the catheter ablation provides long-term ventricular tachycardia control during the long-term follow-up.

Electrochemical Determination of Levodopa Using Zinc Sulfide Nanospheres-Reduced Graphene Oxide

Zinc sulfide nanospheres (ZnS NSs) were prepared by hydrothermal synthesis and graphene oxide (GO) was prepared by the Hummer's method. ZnS NSs-rGO/ITO electrode was synthesized by heat treatment at a certain temperature, which was used for the detailed electrochemical determination of levodopa (LD). Finally, they were annealed to form the ZnS NSs-rGO/ITO electrode for detecting levodopa (LD). The results reveal that the ZnS NSs with the diameter of ~1 μm are covered by rGO. The ZnS NSs-rGO/ITO electrode has a good sensitivity of 1.43 μA μM ^-1 for the determination of LD in the concentration range of 1-40 μM. Moreover, it also shows a good selectivity, reproducibility and stability. In order to verify the practicability, we also use the electrode to detect LD in human serum. The detection results also prove that the electrode can be used in real life.

[Identification of factors affecting Oncomelania hupensis density in Eastern Dongting Lake regions]

OBJECTIVE

To evaluate the impact of water pollutants, water levels and meteorological factors on the Oncomelania hupensis density in Eastern Dongting Lake regions, so as to provide insights into schistosomiasis control.

METHODS

O. hupensis snails were surveyed using a systematic sampling method in snail-infested marshlands in Eastern Dongting Lake regions from 2007 to 2014, and data pertaining to water pollutants, water levels and meteorological factors were collected. The duration of submergence and the date of the start of submergence were calculated. The snail density and its influencing factors were descriptively analyzed, and a linear mixed model was generated to examine the impacts of variables on the snail density. In addition, smooth curves were fitted to investigate the relationship between snail density and variables.

RESULTS

The snail density appeared a fluctuation in Eastern Dongting Lake regions during the period from 2007 to 2014, with the highest density on October, 2010 (52.79 snails/0.1 m²) and the lowest density on January 2009 (2.15 snails/0.1 m²). Linear mixed-model analysis showed that permanganate index, total phosphorus and the date of the start of submergence affected the snail density (t = 6.386, -2.920 and -3.892, all P values < 0.01). Smooth curve analysis revealed that the associations of the snail density with the permanganate index and total phosphorus appeared an approximately quadratic curve. After the end of April, the earlier date of the start of submergence resulted in a higher snail density.

CONCLUSIONS

Permenganate index, total phosphorus and the date of the start of submergence affect the O. hupensis snail density in Eastern Dongting Lake regions.

[Curative effect analysis of ultrasound-guided percutaneous radiofrequency ablation for caudate lobe hepatocellular carcinoma]

Objective: To investigate the safety and efficacy of ultrasound-guided percutaneous radiofrequency ablation (RFA) for caudate lobe hepatocellular carcinoma (HCC) and the failure factors of incomplete tumor ablation. Methods: Twenty-four cases with caudate lobe hepatocellular carcinoma who underwent ultrasound-guided percutaneous RFA in the Affiliated Tumor Hospital of Zhengzhou University from January 2017 to October 2019 were enrolled. The ablation effect and complications conditions were recorded, and the primary technical effectiveness and local tumor progression (LTP) were evaluated. Results: Among 24 cases, 20 cases had complete ablation at one session, 4 cases had incomplete ablation, and after supplementary radiofrequency ablation all cases had achieved complete ablation. There was no evidence of local tumor progression in 24 cases after one-month postoperative evaluation. The primary technical effectiveness rate was 100%. The postoperative follow-up was 2 to 29 months (median follow-up time was 18 months). Of the 24 cases after ablation, LTP were detected in 11 cases, of which only 3 cases had distant intrahepatic recurrence, 1 case had distant intrahepatic recurrence and distant metastasis, and 5 cases had only distant metastasis, 2 cases died, and 4 cases had SIR grade B complications related to ablation. Conclusion: Ultrasound-guided percutaneous radiofrequency ablation was safe and effective for caudate lobe hepatocellular carcinoma. In addition, the distance between the tumor and the inferior vena cava < 0.5cm is a suspected risk factor for incomplete ablation of caudate lobe hepatocellular carcinoma (P < 0.05).

[A rare anatomical variation of ileocolic veins involving in gastrocolic vein trunk: case report and literature review]

Objective: Due to its various anatomical variations and numerous branches, the gastrocolic vein trunk (Henle trunk) is the most common site to develop bleeding and other complications in laparoscopic right hemicolectomy for colon cancer. This study aims to investigate the role of ileocolic vein (ICV) joining with Henle trunk, a rare anatomical variation. Methods: A rare case whose ICV was newly found to involve in the formation of Henle trunk during laparoscopic resection of right hemicolon cancer was reported as right gastroepiploic vein+ right colic vein+superior right colic vein+ICV. This anatomical variation was confirmed by multi-slice spiral CT coronal two-dimensional reconstruction of right hemicolon angiography. The literatures about ICV participating in formation of Henle trunk were systematically searched from PubMed, The Cochran Library, CNKI net and Wanfang database, and the occurrence probability and composition of its anatomical variation were analyzed. Results: This was a 47-year-old female patient who underwent laparoscopic right hemicolectomy. When the vessels were dissected during operation, it was found that ICV did not accompany the ileocolic artery, but directly flowed into Henle trunk. Two-dimensional reconstructed CT images of right hemicolon vessels showed that the composition of Henle trunk was rarely varied, which was composed of right gastroepiploic vein, right colonic vein, superior right colonic vein and ICV. Five literatures were enrolled from literature retrieval. A total of 12 cases with ICV participating in the construction of Henle trunk were reported, with a probability of 0.27%-6.31% and 6 forms of the formation of Henle trunk. In this case, Henle trunk was made up of right gastroepiploic vein, right colonic vein, upper right colonic vein and ICV, which was reported for the first time. Conclusions: ICV involving in Henle trunk is a rare vascular variation, and this type of variation should be fully recognized. Careful dissection during operation is necessary to prevent intraoperative bleeding caused by improper operation.

[Interpretation of global colorectal cancer statistics]

The increasing disease burden caused by colorectal cancer has become one of the major public health problems. This paper analyzes the global statistical data of colorectal cancer, including the morbidity, mortality and case survival, to understand the differences in its age, gender, regional and site specific distributions as well as its incidence trend. The results showed that the programs on colorectal cancer prevention and control varied with country and region. It is necessary to promote developed countries to share their experiences in colorectal cancer prevention and control with developing countries and develop and implement targeted colorectal cancer prevention and control strategies to address the more severe challenge of colorectal cancer.

[Association between obesity and risk for colorectal advanced adenoma]

Objectives: To understand the association between obesity and the risk for colorectal advanced adenoma. Methods: Community residents aged 45 to 74 who had participated in the Shanghai community-based colorectal cancer (CRC) screening project in 2008 were included in our study. Anthropometries information including body weight, height and risk factors for colorectal advanced adenoma were collected. Results on colonoscopic diagnosis and personal health records were used for supplementary outcome information retrieval. Multivariate Cox proportional hazard regression models were used to evaluate the hazard ratio (HR) and 95%CI of obesity on the risk for colorectal advanced adenoma. Results: 20 811 residents were followed up for 122 739.36 person-years, with a median follow-up time of 5.87 years. A total of 657 cases of advanced adenomas were identified. After adjusting for potential confounding risk factors such as age, sex, family history of CRC, level of education, marriage, cigarette smoking, alcohol drinking, foods intake including fat, fried or pickled, vegetables and fruits etc., the HR was 1.25 (95%CI: 1.04-1.51) for obese people when compared with the normal weight persons. Further stratified analysis by age, gender and family history of CRC, results showed that obese people had a much higher risk of colorectal advanced adenoma than those with normal weight (male: HR=1.57, 95%CI: 1.20-2.04; more than 60- year-old: HR=1.63, 95%CI: 1.23-2.16). Conclusion: Data from this large scale population-based study revealed that obesity might be an independent risk factor for colorectal advanced adenoma and the risk increases along with the increase of BMI in China.

[Application effects of self-made simple vacuum sealing drainage device in postoperative treatment of sural neurocutaneous flap transplantation in the foot and ankle]

Objective: To investigate the application effects of self-made simple vacuum sealing drainage (VSD) device in the postoperative treatment of sural neurocutaneous flap transplantation in the foot and ankle. Methods: From January 2017 to January 2019, 36 patients with foot and ankle skin defects and bone exposure admitted to People's Hospital of Xinjiang Uygur Autonomous Region met the inclusion criteria, and a retrospective cohort study was conducted. According to the bandaging method of the operative area, simple negative pressure group and antibacterial dressing group were both allocated with 18 patients, with 12 males and 6 females in the former group, 14 males and 4 females in the latter group, aged (41.6±2.8) and (42.3±2.6) years, respectively. Patients in the two groups all received sural neurocutaneous flap transplantation. Patients in antibacterial dressing group received nano silver antibacterial dressing change in the operative area, and the dressing was changed once every 3 days. In simple negative pressure group, the operative area was sealed with a simple VSD device made of gauze, silicone sputum suction tube with holes cut out, and biological permeable membrane, etc., which was connected with the wall central negative pressure suction system for continuous VSD treatment of -40.0 to -16.6 kPa. The negative pressure material was changed once every 5 days. The number of dressing change, the pain score evaluated by Numeric Rating Scale during each dressing change, the cost of dressing change, and the degree of flap swelling evaluated on the 3rd and 5th day after surgery were recorded, and the flap survival was observed. Data were statistically analyzed with independent sample t test, Wilcoxon rank sum test, and chi-square test. Results: The number of dressing change of patients in simple negative pressure group was (3.4±0.5) times, which was significantly less than (7.0±0.8) times in antibacterial dressing group (t=15.338, P<0.01). The pain score during dressing change of patients in simple negative pressure group was (4.3±0.8) points, which was significantly lower than (6.8±0.7) points in antibacterial dressing group (t=10.168, P<0.01). The cost of dressing change of patients was similar between the two groups. On the 3rd and 5th day after surgery, the degrees of flap swelling of patients in simple negative pressure group were significantly superior to those in antibacterial dressing group (Z=4.448, 2.395, P<0.05 or P<0.01). The flap survival of patients in simple negative pressure group was significantly superior to that in antibacterial dressing group (χ(2)=4.500, P<0.05). Conclusions: Compared with the traditional dressing bandage, the self-made simple VSD device used after sural neurocutaneous flap transplantation can reduce the frequency of dressing change, relieve the pain of dressing change and the swelling of flap, and promote the flap survival, which is worth popularizing and applying in clinic.

[Construction of a new anti-CD123 chimeric antigen receptor T cells and effect of anti-acute myeloid leukemia]

目的

构建一种新的靶向CD123的嵌合抗原受体T细胞(CAR-T细胞)，为CD123阳性白血病的免疫治疗提供实验参考。

方法

通过单克隆筛选技术获得能稳定分泌CD123抗体的杂交瘤细胞株6E11，将杂交瘤细胞扩增后腹腔注射至Balb/c小鼠腹腔内，收集腹水并处理、纯化得到单克隆抗体，测定抗体效价并对其特异性进行验证；RT-PCR法获得轻链和重链可变区序列，并以此为基础利用分子克隆技术构建一种新的靶向CD123嵌合抗原受体，包装病毒后感染T细胞制备CD123CAR-T细胞，通过功能实验初步探讨6E11CAR-T细胞体外抗白血病的能力。

结果

①获得1株稳定分泌抗人CD123抗体的杂交瘤细胞株6E11并获得其可变区序列。②6E11单克隆抗体对CD123蛋白亲和性高，解离常数(K_d值)为2.10nmol/L，特异性识别CD123阳性细胞且与CD123阴性细胞无交叉反应。 ③成功构建了CD123CAR慢病毒载体，感染T细胞后获得了靶向CD123的CAR-T细胞(6E11CAR-T)，感染效率大于60％。 ④6E11CAR-T能明显杀伤CD123阳性靶细胞MV4-11，效靶比1∶1时6E11CAR-T细胞对MV4-11细胞的杀伤比例明显高于 Vecor-T细胞[(98.60±1.20)％对(20.28±6.74)％，P<0.001]，但对CD123阴性靶细胞K562没有明显杀伤作用。 ⑤MV4-11细胞可以显著激活6E11CAR-T，但对Vecor-T细胞无明显激活作用[(26.33±3.30)％对(1.17±0.06)％，P<0.001]。⑥6E11CAR-T与MV4-11细胞共培养上清中细胞因子水平均显著高于Vecor-T组[IL-2：(92.90±1.51)pg/ml对(6.05±3.41)pg/ml，P<0.001；TNF-α：(1 407.20±91.95)pg/ml对(7.86±0.85)pg/ml，P<0.001；IFN-γ：(5 614.60±170.17)pg/ml对(8.42±2.70)pg/ml，P<0.001]但与 K562细胞共培养后，两组各细胞因子水平差异无统计学意义。 ⑦6E11CAR-T在与CD123阳性髓系白血病(AML)原代细胞共培养过程中被显著激活，且能有效杀伤原代 AML细胞。

结论

杂交瘤细胞株6E11能稳定分泌高效特异的抗人CD123单克隆抗体，可用于检测表达人CD123的细胞，也能应用在靶向人CD123蛋白的肿瘤免疫治疗中，以 6E11Ig可变区序列为抗原识别区的CD123CAR-T细胞，具有明确的体外抗白血病活性，为进一步的临床研究奠定了基础。

[A clinical performance study of modified CT angiography in detecting bronchial artery-pulmonary artery fistula]

Objective: To evaluate the clinical value of modified computed tomography angiography(CTA) in detecting bronchial artery-pulmonary artery fistula(BPF). Methods: Retrospective analysis was performed on 246 patients with hemoptysis admitted to the First Affiliated Hospital of Wenzhou Medical University from July 2017 to December 2018, who underwent modified CTA and DSA examination at the same time. CT was performed with Toshiba Aquilion one 320 row 640-slice spiral CT scanner. All modified CTA images were read blindly by two radiologists above the attending doctors. The sensitivity, specificity and accuracy of the modified CTA in diagnosing BPF were calculated with the DSA results as the reference,and the consistency of the two tests was analyzed. Results: DSA detected 186 cases of positive and 60 cases of negative, modified CTA detected 160 cases of positive and 86 cases of negative. The sensitivity,specificity and accuracy of modified CTA for BPF diagnosis was 85.5%(159/186),98.3%(59/60), 88.6%(218/246) respectively, and they were with high consistency with DSA examination results (kappa=0.73,P<0.01). Conclusion: Modified CTA has high diagnostic specificity for BPF,which can be used as the preferred method for non-invasive screening of suspected BPF patients.

[The value of (18)F-fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG PET-CT) in evaluating the stability of atherosclerotic plaques]

Objective: Positron emission tomography-computed tomography (PET-CT) has been used to quantify inflammatory response in the body. The aim of the present study was to explore the possibility of using this method to evaluate the stability of atherosclerotic plaques and the efficacy of atorvastatin in stabilizing atherosclerotic plaques. Methods: Twenty New Zealand male white rabbits were included and divided into the atorvastatin intervention group and the control group, with 10 rabbits in each group. Rabbits in both groups were fed with a high fat diet for 20 weeks, and treated with thoracoabdominal aortic balloon-pulling to establish atherosclerosis model at the end of the 2nd week. Rabbits in atorvastatin intervention group was given atorvastatin intragastrically once a day. At the 8th week, thoracoabdominal aortic ultrasound was used to detect plaques in all rabbits. Blood was drawn at the 3rd and the 20th week, respectively, to measure blood lipids, high-sensitive C-reactive protein (hs-CRP) and matrix metalloproteinase-9 (MMP-9). At the end of experiment, survival animals were scanned by (18)F-FDG PET-CT, and the average and maximum standard uptake values (SUVmean, SUVmax) of aortic segments were measured. Thereafter, the animals were sacrificed and aortic specimens of rabbits were taken and examined by immunohistochemistry. The pathological indexes were measured and compared. Results: At the end of experiment, the total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), hs-CRP [ (4.58±0.51) ng/ml vs.(5.87±0.66) ng/ml, P<0.01], MMP-9[ (43.93±2.16) ng/ml vs. (50.77±2.32) ng/ml, P<0.01], SUVmean (0.59±0.15 vs. 0.68±0.20, P<0.05) , SUVmax (0.68±0.20 vs. 0.81±0.27, P<0.05) , plaque area [ (0.36±0.24) mm(2) vs. (0.50±0.34) mm(2), P<0.05) ] and density of macrophage[ (4.34±1.54) % vs. (5.65±1.89) %, P<0.01] in the atorvastatin intervention group were significantly lower than those in the control group. In contrast, fiber cap thickness of the plaque[ (4.12±0.66) μm vs. (2.96±0.37) μm, P<0.01] in the atorvastatin intervention group was higher than that of the control group, and the difference was statistically significant. The arterial plaque areas were positively correlated with SUVmean (r=0.27, P<0.05) and SUVmax (r=0.43, P<0.01) . Fiber cap thickness was negatively correlated with SUVmean (r=-0.38, P<0.05) and SUVmax (r=-0.47, P<0.01) . The density of macrophage were positively correlated with SUVmean (r=0.52, P<0.01) and SUVmax (r=0.51, P<0.01) . Conclusion: (18)F-FDG PET/CT can be used to evaluate the efficacy of atorvastatin by the stability of atherosclerotic plaques.

[Efficacy of first generation EGFR-TKIs and chemotherapy as first-line therapy in advanced lung adenocarcinoma patients with uncommon EGFR mutations]

Objective: To investigate the clinical effects of first generation epithelial growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) compared with platinum-based chemotherapy as first-line therapy in advanced lung adenocarcinoma patients with uncommon EGFR mutations. Methods: Clinical data of 4 276 patients diagnosed as advanced lung adenocarcinoma (ⅢB/Ⅳ) underwent EGFR gene detection at the Affiliated Cancer Hospital of Zhengzhou University from January 2012 to February 2018 were collected and 99 cases with uncommon EGFR mutations were selected. The clinical pathological features, treatment outcomes, treatment options and prognosis after first-line treatment of the 99 cases were analysed and compared with other patients with common EGFR mutations. Results: The objective response rates of patients with uncommon EGFR mutations receiving EGFR-TKIs or platinum-based chemotherapy were 33.0% and 27.1%, respectively. The disease control rates were 76.5% and 87.5%, respectively. The progression-free survival (PFS) of patients treated with EGFR-TKIs was 7.2 months, significantly superior than 4.9 months of patients receiving chemotherapy (P=0.009). The overall survival of patients treated with EGFR-TKIs was 14.3 months, significantly worse than 20.7 months of patients receiving chemotherapy (P=0.034). Multivariate analysis showed that distant metastases (P=0.001) and smoking history (P=0.013) were independent prognostic factors for OS of lung adenocarcinoma patients with EGFR uncommon mutations. Conclusions: Compared with chemotherapy, the usage of first generation of EGFR-TKIs as first-line therapy can improve the short-term efficacy of advanced lung adenocarcinoma patients with EGFR uncommon mutations. However, platinum-based chemotherapy shows a longer overall survival.

[A decade's review for the foundation, establishment and development of the Department of Minimally Invasive Gastrointestinal Surgery in Peking University Cancer Hospital]

Department of minimally invasive gastrointestinal surgery in Peking University Cancer Hospital (also named as Department of Gastrointestinal Surgery IV) was established on April 7, 2009. Up to now, ten years have passed since its foundation. As the first department built in specialized cancer hospital, which mainly focuses on laparoscopic surgery, its foundation and development has a very important historical and practical significance in the development of surgical oncology in China. Reviewing the rapid growth of the Department of Minimally Invasive Gastrointestinal Surgery over the past decade, on the one hand, it has benefited from the opportunities of the times and the support of leaders in Peking University Cancer Hospital at that time. More importantly, the progress owes to the pioneering Professor Su Xiangqian, who is brave and innovative, with indomitable spirit and advanced management philosophy. With rigorous training, the ability of the team has been steadily enhanced, the competitiveness has been gradually improved, and the development direction which focuses on laparoscopic gastric cancer surgery and laparoscopic colorectal cancer surgery has been established. Now, the Department of Minimally Invasive Gastrointestinal Surgery has become a well-known domestic gastrointestinal tumor center. In the past ten years, under the leadership of Professor Su Xiangqian, the growth of this team is innovative and comprehensive: (1) Introduce the internationally advanced Baldrige medical service management framework, and propose the "management by principle" concept to improve the core competitiveness of the department; (2) Establish an academic brand by laparoscopic standardized surgery training courses for gastrointestinal tumors, promote cooperation and exchange at home and abroad, and participate in international multi-center clinical research projects; (3) Adhere to the "formation of a research-oriented department, conducting clinical and basic research simultaneously" as the development direction; (4) Stick to the core development concept of team building and cultivate professional talents. Looking forward to the future, our team will not forget the beginning of the heart, and move forward! In the next ten years, we will break through ourselves and continue to pursue the higher level!

Colloidal-electrochemical fabrication strategies for functional composites of linear polyethylenimine

Colloidal-electrochemical fabrication strategies have been developed for the deposition of linear polyethylenimine (LPEI) composite materials. Electrophoretic deposition (EPD) allowed for the fabrication of composite films containing Mn₃O₄ and ZnO nanoparticles, as well as advanced flame retardant materials, such as halloysite nanotubes and memory-type Al-Mg-Zr complex hydroxide (AMZ) in the matrix of the water-insoluble LPEI. A liquid-liquid extraction method has been designed for the agglomerate-free processing of AMZ particles. Efficient extraction was achieved using decylphosphonic acid as an extractor. A conceptually new polymer complex (PC)-EPD method has been developed, which is based on the use of LPEI-metal ion complexes. Proof-of-concept studies involved the fabrication of LPEI-Ni(OH)₂ and LPEI-MnOx nanocomposites. The composites showed valuable flame retardant and charge-storage properties. The analysis of basic EPD and PC-EPD mechanisms as well as complexing properties of LPEI has driven the development of new strategies for the fabrication of organic composites. Hemoglobin was used as a model protein for the fabrication of composite films. Another important finding was the fabrication of composites, containing cyclodextrin, which is a unique carrier of various functional organic molecules. EPD and PC-EPD are versatile methods, which allow for the deposition of novel LPEI based composites containing various functional materials.

[Clinical significance of recombinant virus-specific detection for viable circulating tumor cells in lung cancer patients]

Objective: To investigate the clinical significance of recombinant virus-specific detection for detecting viable circulating tumor cell (CTC) in lung cancer patients. Methods: From June 2017 to August 2018, 63 lung cancer patients diagnosed by imaging and pathology at the Department of Respiratory and Critical Care Medicine, Beijing Anzhen Hospital were recruited for this study, including 38 cases of adenocarcinoma, 13 squamous cell carcinoma, and 12 small cell carcinoma. The patients consisted of 36 males and 27 females, with an average age of (65±11) years. In addition,21 patients with benign lung diseases were recruited for benign lung disease group, including 11 males and 10 females with an average age of (57±13) years. Another 18 healthy subjects were recruited for the healthy control group, including 10 males and 8 females, with an average age of (32±10) years. The peripheral blood viable CTCs were detected by a CTC in vitro detection kit containing recombinant virus. Fisher's exact test was used to compare the differences between the groups of viable CTC positive rates. Results: Cases with positive viable CTC in the lung cancer group, the benign lung disease group and the healthy control group were 56,4 and 0, respectively. The sensitivity and specificity of this CTC detection system were 89% (56/63) and 90% (35/39) , respectively. The positive rate of CTC detection for lung cancer patients with adenocarcinoma, aquamous cell carcinoma, and small cell carcinoma, were 84%(32/38), 92% (12/13) and 100% (12/12), respectively. The positive cases from adenocarcinoma and squamous cell carcinoma patients with different stages were 2 (n=2) in stageⅠ,6 (n=8) in stage Ⅱ,7(n=8) in stage Ⅲ and 29(n=33) in stage Ⅳ. There were no significant differences in the positive rates of CTC among different histological types or different stages (χ(2)=1.881, 3.419; P>0.05) . Conclusion: This CTC detection system was found to be a simple and non-invasive method for auxiliary diagnosis of lung cancer, with high sensitivity and specificity.

[Clinical analysis of 5 cases of endobronchial hamartoma]

Objective: To analyze the clinical manifestations of patients with endobronchial hamartoma(EH),and therefore to improve understanding of the disease. Methods: Data were retrospectively reviewed to describe the clinical characteristics, diagnosis procedures and prognosis of EH, including 5 patients in Beijing Anzhen Hospital, Capital Medical University from Jun 2007 to Feb 2018 and another 159 patients from Chinese and English literatures published after Jan 2000. Results: The five patients, 4 males and 1 female, aged from 46 to 69 years[mean (56±7) years], were diagnosed with EH in our hospital. There was no fever in the 5 cases, cough and expectoration in 4 cases, hemoptysis in 3 cases and asymptomatic in 1 case. Chest CT revealed that the lesions of all 5 cases were located in the right bronchial tube; 3 as high-density endobronchial mass, 1 as low-density mass, 1 as mixed density mass, and 1 as a "popcorn" lesion. Three cases were accompanied by obstructive pneumonia in the distal part of the EH and 2 cases by atelectasis. CT enhanced scan was performed in 5 cases, 2 showing no enhancement and 3 showing mild enhancement. Four cases showed polyposis under bronchoscopy, and 5 cases received bronchoscopic biopsy with 3 pathologically diagnosed as EH. Four of them received lobectomy, while 1 received removal by biopsy forceps, and all were pathologically confirmed as EH. There was no evidence of recurrence in these 5 patents with follow-up. Conclusions: EH was a rare benign bronchial tumor with nonspecific clinical and imaging manifestations. Endobronchial polyposis could be revealed by bronchoscopy, and pathological study is required to confirm the diagnosis.

[Factors associated with illicit drug use intention in secondary vocational school students based on theory of triadic influence]

Objective: To explore the factors associated with illicit drug use (IDU) intention in secondary vocational school students based on theory of triadic influence (TTI), and provide theoretical foundation for IDU prevention education. Methods: A total of 8 870 students were selected from secondary vocational schools in 5 cities in China through multistage cluster sampling. A self-administered questionnaire was used to collect the information about students' sensation seeking (SS), parental monitoring (PM), perceived availability of drug (PAD), social benefit expectancies(SBE), refusal efficacy (RE) and social norms and IDU intention. Based on the TTI, the logistic regression model was used to analyze the factors associated with IDU. Results: Among the intrapersonal stream of influence, the higher levels of SS was the risk factor associated with IDU (OR=1.71, 95%CI: 1.22-2.41, P<0.01), medium RE level (OR=0.18, 95%CI: 0.14-0.23, P<0.001) and high RE level (OR=0.17, 95%CI: 0.13-0.22, P<0.001) were the protective factors for IDU intention. Among the interpersonal stream of influence, medium PM level (OR=0.46, 95%CI: 0.37- 0.56, P<0.001) and high PM level (OR=0.33, 95%CI: 0.24-0.46, P<0.001) were the protective factors for IDU intention, perceived others' drug use as well as perceived others' approval of substance use were risk factors for IDU intentions (P<0.001); Among sociocultural environmental stream of influence, perceived easy availability of drugs (OR=3.47, 95%CI: 2.69-4.48, P<0.001) and perceived SBE of drugs (OR=2.04, 95%CI: 1.69-2.46, P<0.001) were risk factors for IDU intentions (P<0.001). Conclusions: High levels of SS and SBE, perceived easier availability of substance, perceived others' substance use and perceived others' approval of substance use positively predict the students' intention of IDU. IDU prevention education for adolescents should be focused on the above factors, and parental supervision and students' refuse skills should be improved.

Anti-atherosclerotic effect of Longxuetongluo Capsule in high cholesterol diet induced atherosclerosis model rats

Chinese dragon's blood, the red resin of Dracaena cochinchinensis, one of the famous traditional medicines, has been used to promote blood circulation, disperse blood stasis, stop bleeding, relieve pain and muscle regeneration for thousands of years. The aims of this study were to evaluate the anti-atherosclerotic effect of Longxuetongluo Capsule (LTC), which made by total phenolic compounds of Chinese dragon's blood, in high cholesterol diet (HCD)-induced atherosclerosis model rats and explore the possible mechanism. Atherosclerosis rats were induced by administration of HCD for 4 weeks and treated with atorvastatin (2.08mg/kg/d) or various concentrations of LTC (81, 162 and 324mg/kg/d) for additional 4 weeks. Body weight (BW), lipid profiles, serum VCAM-1, ICAM-1, MCP-1, AST and ALT were then tested. Histopathological evaluation of aorta and liver were determined by hematoxylin and eosin staining. NF-κB expression in aorta was detected by Immunohistochemical staining. Meanwhile, the inhibition effects of LTC on the migration and proliferation and Intracellular Ca²⁺ levels induced by PDGF-BB were also evaluated in rat aortic smooth muscle cells (A7r5). The results demonstrated that LTC produced a significant anti-atherosclerotic activity in terms of reduction in serum lipids and lipoprotein profile, VCAM-1, ICAM-1, MCP-1, AST, ALT levels, and increase in HDL-c level compared to atherosclerotic group. Rats treated with LTC not only attenuated the pathological region and atheroma formation, but also reduced hepatic steatosis and inflammatory cell infiltration. Immunohistochemical analysis showed LTC reduced NF-κB expression in aorta. Furthermore, PDGF-BB induced proliferation and migration of A7r5 and intracellular calcium rise were also abrogated by LTC. The results indicate that LTC prevents atherosclerosis and fatty liver by controlling lipid metabolism, the underlying mechanism may attributed to its anti-inflammation activity, regulation of the vascular smooth muscle function and intracellular calcium signaling.

[Prevalence and risk factors of respiratory viral infection in acute exacerbation of chronic obstructive pulmonary disease]

Objective: To study the prevalence of respiratory viral infection in chronic obstructive pulmonary disease(COPD) exacerbations and to find the factors associated with susceptibility to viral infections. Methods: Eighty patients with exacerbations of COPD and 50 stable COPD patients were recruited. Nasopharyngeal swabs were tested for a range of 18 different respiratory viruses using PCR. Results: Among the COPD exacerbations, viral infection was detected in 18 episodes (22.5%) . The most common virus was rhinovirus (33.3%), followed by coronavirus(27.8%), parainfluenza(22.2%), metapneumovirus(11.1%) and influenza virus B(5.6%). The prevalence of viral infection was 8% in the stable COPD patients. In multivariate regression analysis fever was found to be significantly associated with viral infections in COPD exacerbations (Odds ratio 4.99, 95%CI 1.51-16.48, P=0.008). Conclusion: Viral respiratory pathogens were more often detected in respiratory specimens from hospitalized patients with AECOPD than those with stable COPD. Rhinovirus was the most common infecting agent identified. The symptom of fever was associated with viral detection.

[Analysis on the risk factors of diabetic foot ulcer in diabetic patients of Uyghur nationality and Han nationality in the Xinjiang Uygur Autonomous Region]

Objective: To explore the risk factors of diabetic foot ulcer (DFU) in diabetic patients of Uyghur nationality and Han nationality in the Xinjiang Uygur Autonomous Region. Methods: Clinical data of 640 diabetic patients admitted to our ward from January 2015 to November 2016, conforming to the study criteria, were retrospectively analyzed. Patients were divided into DFU group (n=403) and non-DFU group (n=237) according to whether DFU occurred or not. The data of gender, age, nationality, body mass index (BMI), smoking, drinking, binge eating, triglyceride (TG), total cholesterol (TC), and high-density lipoprotein (HDL) of patients between two groups were compared with chi-square test and t test. Indexes with statistically significant differences between two groups were selected, and they were processed with non-conditional multivariate logistic regression analysis to screen the independent risk factors of DFU. The possible risk factors of DFU of patients of Uyghur nationality and Han nationality were further processed with non-conditional multivariate logistic regression analysis respectively to screen the independent risk factors of DFU of patients of Uyghur nationality and Han nationality. Results: (1) There were no statistically significant differences in gender, age, TC, and HDL of patients between two groups (with χ(2)=0.149, t values respectively 1.163, 1.033, and 1.026, P values above 0.05). There were statistically significant differences in nationality, BMI, smoking, drinking, binge eating, and TG of patients between two groups (with χ(2) values from 4.778 to 13.694, t values respectively 4.703 and 4.237, P<0.05 or P<0.01). (2) Nationality, BMI, smoking, drinking, binge eating, and TG were the independent risk factors of DFU(with odds ratios respectively 1.488, 1.527, 1.736, 1.738, 1.382, and 1.648, 95% confidence intervals respectively 1.315-3.175, 1.488-4.393, 1.834-4.675, 1.474-2.695, 1.342-4.678, and 1.105-6.747, P values below 0.05). (3) Smoking, drinking, binge eating, and TG were the independent risk factors of DFU in diabetic patients of Uyghur nationality (with odds ratios respectively 1.673, 1.387, 1.328, and 1.486, 95% confidence intervals respectively 1.384-1.765, 1.414-1.659, 1.423-1.687, and 1.150-1.670, P values below 0.05). BMI, smoking, and drinking were the independent risk factors of DFU in diabetic patients of Han nationality (with odds ratios respectively 2.442, 1.604, and 1.251, 95% confidence intervals respectively 2.223-2.699, 1.268-2.028, and 1.164-1.344, P<0.05 or P<0.01). Conclusions: Smoking, drinking, binge eating, and TG were the independent risk factors of DFU in diabetic patients of Uyghur nationality. BMI, smoking, and drinking were the independent risk factors of DFU in diabetic patients of Han nationality.

[Association between single nucleotide polymorphism of BARD1 gene and BRCA1 gene mutation in epithelial ovarian cancer]

Objective: To investigate the relationship between single nucleotide polymorphism (SNP) of BARD1 gene and BRCA1 gene in epithelial ovarian cancer (EOC). Methods: Nineteen EOC patients with BRCA1 gene mutation and 50 EOC cases without BRCA1 gene mutation between January 2016 and October 2016 were collected, and all EOC were diagnosed by pathological method. BARD1 gene variants were detected by next generation sequencing (NGS). The SNP of BARD1 gene was analyzed by Pearson linear correlation. Logistic regression analysis was used to research the clinicopathologic features and BRCA1 gene mutation associated with BARD1 gene SNP. Pearson's chi-square test was used to analyze the association between BARD1 gene Val507Met, Arg378Ser and Pro24Ser with different clinicopathologic features and BRCA1 gene mutation risk. Results: (1) Eight BARD1 gene variants were found in 69 ovarian cancer patients, in which Val507Met, Arg378Ser and Pro24Ser were common variants, and the rate of mutation were all 54% (37/69). (2) There was a significant linear correlation among Val507Met, Arg378Ser and Pro24Ser (all P<0.01). (3) Obvious differences were found in Val507Met, Arg378Ser and Pro24Ser of BARD1 gene between BRCA1(+) and BRCA1(-) (all P<0.05) . (4) No differences were found between BARD1 gene Val507Met, Arg378Ser and Pro24Ser and the clinicopathologic features (all P>0.05), while obvious differences were found in BRCA1 gene mutation compared to the controls group. The risk of BRCA1 mutation in Val507Met and Arg378Ser were more evident in subjects with negative family history, positive menopause history, negative tubal ligation, onset age (≤60 years old) and sensitivity to platinum-based chemotherapy in EOC (all P<0.05), while Pro24Ser was only more evident in positive menopause history of EOC (P<0.05). Conclusions: BARD1 Val507Met, Arg378Ser and Pro24Ser are the common genotypes, which are associated with BRCA1 mutation in EOC. The family history, menopause history, tubal ligation, onset age and sensitivity to platinum-based chemotherapy have effects on BARD1 SNP in the risk of BRCA1 gene mutation.

[Clinical significance and distribution of BRCA genes mutation in sporadic high grade serous ovarian cancer]

Objective: To investigate the mutations of BRCA genes in sporadic high grade serous ovarian cancer (HGSOC) and study its clinical significance. Methods: Sixty-eight patients between January 2015 and January 2016 from the Affiliated Cancer Hospital of Zhengzhou University were collected who were based on pathological diagnosis of ovarian cancer and had no reported family history, and all patients firstly hospitalized were untreated in other hospitals before. (1) The BRCA genes were detected by next-generation sequencing (NGS) method. (2) The serum tumor markers included carcinoembryonic antigen (CEA), CA(125), CA(199), and human epididymis protein 4 (HE4) were detected by the chemiluminescence methods, and their correlation was analyzed by Pearson linear correlation. Descriptive statistics and comparisons were performed using two-tailed t-tests, Pearson's chi square test, Fisher's exact tests or logistic regression analysis as appropriate to research the clinicopathologic features associated with BRCA mutations, including age, International Federation of Gynecology and Obstetrics (FIGO) stage, platinum-based chemotherapy sensitivity, distant metastases, serum tumor markers (STM) . Results: (1) Fifteen cases (22%, 15/68) BRCA mutations were identified (BRCA1: 11 cases; BRCA2: 4 cases), and four novel mutations were observed. (2) The levels of CEA, CA(199), and HE4 were lower in BRCA mutations compared to that in control group, while no significant differences were found (P>0.05), but the level of CA(125) was much higher in BRCA mutation group than that in controls (t=-3.536, P=0.003). Further linear regression analysis found that there was a significant linear correlation between CA(125) and HE4 group (r=0.494, P<0.01), and the same correlation as CEA and CA(199) group (r=0.897, P<0.01). (3) Single factor analysis showed that no significant differences were observed in onset age, FIGO stage, distant metastasis, and STM between BRCA(+) and BRCA(-) group (P>0.05), while significant differences were found in CA(125) and sensitivity to platinum-based chemotherapy between the patients with BRCA mutation and wild type (P<0.05). The multiple factors analysis showed that the high level of CA(125) was a independent risk factor of BRCA mutations in sporadic HGSOC (P=0.007). Conclusion: The combination of CA(125) with BRCA have great clinical significance, the mutation of BRCA gene could guild the clinical chemotherapy regiments.

[Effect of epigallocatechin-3-gallate on the proliferation and osteogenesis of human periodontal ligament cells]

Objective: To evaluate the effect of epigallocatechin-3-gallate (EGCG) treatment on the proliferation and osteogenic differentiation of human periodontal ligament cell (hPDLC) and to explore the potential role of EGCG in promoting periodontal hard tissue regeneration. Methods: The hPDLC was isolated from periodontal ligament tissue obtained from freshly extracted human teeth. The effect of treatments with various concentrations of EGCG (0 μmol/L, 2 μmol/L, 4 μmol/L, 6 μmol/L, 8 μmol/L and 10 μmol/L) on cell proliferations were determined by cell counting kits (CCK) after 24-, 48- and 72-hour-incubations, respectively. Osteogenic differentiation abilities of hPDLCs were assessed by using alkaline phosphatase (ALP) activity tests after 7- and 14-day-incubations, respectively. The mineralized nodules were quantitatively examined and analyzed by using alizarin red staining after 21-day-incubation. The real-time PCR (RT-PCR) assays were conducted fordetecting the expressions of Runt related transcription factor-2 (Runx2), ALP and collagen type Ⅰ (COL Ⅰ) after 7-day-incubation. Results: Treatment with 4 μmol/L EGCG increased hDPLC proliferation at 24 h, while 8 μmol/L or 10 μmol/L EGCG treatment groups showed inhibiting effects at 24 h and 72 h, respectively. Findings of alizarin redstaining showed orange to red colored extracellular mineralized nodules in all groups. The the A values of 2, 4, 6, 8, 10 μmol/L EGCG groups were 0.119±0.001, 0.167±0.003, 0.173±0.003, 0.110±0.001 and 0.083±0.003, respectively. A values of 2-8 μmol/L EGCG groups were significantly higher than that of the control group, however there was no significant difference of the A values between10 μmol/L EGCG group and the control group (0.077±0.001). Treatments with 2-10 μmol/L EGCG could significantly increase the mRNA expressions of COL Ⅰ and ALP with the highest values in 4-6 μmol/L EGCG treatment groups. Although treatments with 4 and 6 μmol/L EGCG both could increase the mRNA expressions of Runx2, the result in 4 μmol/L group was much better than that of 6 μmol/L group. Conclusions: Treatment of 4 μmol/L EGCG could promote hPDLC proliferation at early stageand treatments with 4-6 μmol/L EGCG could significantly promote the osteogenesis of hPDLCs which might play a promising role in periodontal hard tissue regeneration.

Identification of key biomarkers involved in osteosarcoma using altered modules

The aim of this study was to screen for key biomarkers of osteosarcoma (OS) by tracking altered modules. Protein-protein interaction (PPI) networks of OS and normal groups were constructed and re-weighted using the Pearson correlation coefficient (PCC), respectively. The condition-specific modules were explored from OS and normal PPI networks using a clique-merging algorithm. Altered modules were identified by a maximum weight bipartite-matching method. The important biological pathways in OS were identified by a pathway-enrichment analysis using genes from disrupted modules. The most important genes in these pathways were selected as key biomarkers. Finally, the mRNA and protein expressions of hub genes in OS bone tissues were analyzed using reverse transcription-polymerase chain reaction and western blotting, respectively. We identified 703 and 2270 modules in normal and disease networks, respectively; 150 altered modules were identified from among these and explored. We identified 10 important pathways based on gene pairs with altered PCC > 1 in the disrupted modules (P < 0.01), and PCNA, ATP6V1C2, ATP6V1G3, FEN1, CDC7, and RPA3 (expressed in these pathways) were selected as key genes of OS. We observed that these genes (and the proteins they encoded) were differentially expressed between normal and OS samples (P < 0.01) (excluding ATP6V1C2, whose protein expression did not differ significantly). Therefore, we identified 5 gene signatures that may be potential biomarkers for the detection and effective therapy of OS.

Large-scale tissue-specific and temporal gene expression profiles in Pengze crucian carp

In the present study, the tissue-specific and temporal gene expression profiles of four catalogues of gonadal development-related genes (sex differentiation-related, steroid receptor, steroidogenic, and structural genes) were detected in nine tissues and during 11 successive developmental stages in the Pengze crucian carp (Pcc) (a triploid mono-female gynogenic fish). The results showed that these target genes exhibited overlapping distributions in various tissues, with the exception of Pcc-vasa and Pcc-cyp17a1. Gene expression profiling of the developmental stages showed that all of the target genes simultaneously reached peak expression levels at 40 and 48 days post hatching (dph). Both 40 and 48 dph appeared to be two key time points associated with the process of Pcc gonadal development. These data will provide a clear understanding of gene expression patterns associated with the gonadal development-related genes of this gynogenic teleost.

[Phosphatase and tensin homolog deleted on chromosome ten/phosphatidyl Inositol 3-kinase/vascular endothelial growth factor signaling pathway changes in the rabbit Kawasaki disease model]

OBJECTIVE

To observe the changes of phosphatase and tensin homolog deleted on chromosome ten(PTEN)/ phosphatidyl Inositol 3-kinase(PI3K)/ vascular endothelial growth factor(VEGF)signaling pathway in a rabbit Kawasaki disease model.

METHODS

Model of Kawasaki disease was established in weanling Japanese big-eared rabbits with 10% bovine serum venous injection (2.5 ml/kg, 2 times, and 2 week's interval) through the ear. Twenty four rabbits were divided into 4 groups: control group (without injection of 10% bovine serum albumin, six rabbits); 1 day group (sacrificed a the second day after the establishment of Kawasaki disease models, six rabbits); 7 day group (sacrificed at the seventh day after establishment of Kawasaki disease model, six rabbits); 30 day group (sacrificed at the thirtieth day after establishment of Kawasaki disease model, six rabbits). Pathological analysis was performed on coronary artery tissue samples. The express of PTEN and PI3K were detected by immunohistochemistry. The levels of VEGF and CK were also examined with ELISA and white blood cells were counted.

RESULTS

(1) Coronary artery of model groups was thinner, distorted and had enlarged lumen. (2) PTEN expression in 1 d group, 7 d group and 30 d group were 58.5 ± 12.9, 73.2±9.9 and 109.6 ± 24.4, respectively, significantly higher than in the control group (25.5 ± 6.9, P<0.01 or 0.05). (3) The express of PI3K was significantly upregulated in 1 d group(57.2±11.1)and 7 d group(39.9±4.8) compared to control group(19.1±3.5, P<0.01 or 0.05). The expression level of PI3K in 30 d group was 18.8 ± 7.5, which was similar as control group (P>0.05) and significantly lower than 1 d and 7 d group (both P<0.05). (4) Similarly, the level of VEGF in 1 d group, 7 d group ((89.1 ± 15.5) ng/L, (76.9±9.9) ng/L) were significantly higher while it was significantly lower in 30 d group ((19.8 ± 4.4)ng/L) compared with the control group ((33.9 ± 6.7) ng/L, P<0.01 or 0.05). The level of VEGF in 7 d group was significantly lower than in 1 d group (P<0.05) and the level of VEGF was significantly lower in 30 d group than in 7 d group (P<0.01). (5)Creatine kinase levels were significantly higher in 30 d group than in control group (P<0.05) and there were no significantly different between control group, 1 d group and 7 d group(all P>0.05). (6)White blood cell count were significantly higher in 1 d group, 7 d group and 30 d group than in control group (all P<0.01).

CONCLUSION

The level of PTEN/PI3K/VEGF signaling pathway change after establishment of rabbit Kawasaki disease model and the signaling pathway might be involved in this model.

Biomass properties and permeability in an immersed hollow fibre membrane bioreactor at high sludge concentrations

This study aimed to investigate the influence of biomass properties and high mixed liquor suspended solids (MLSS) concentrations on membrane permeability in a pilot-scale hollow fibre membrane bioreactor treating domestic wastewater. Auxiliary molasses solution was added to maintain system operation at constant food-to-microorganisms ratio (F/M = 0.13). Various physicochemical and biological biomass parameters were measured throughout the trial, comprising pre-thickening, thickening and post-thickening periods with reference to the sludge concentration and with aerobic biotreatment continuing throughout. Correlations between dynamic changes in biomass characteristics and membrane permeability decline as well as permeability recovery were further assessed by statistical analyses. Results showed the MLSS concentration to exert the greatest influence on sustainable membrane permeability, with a weaker correlation with particle size distribution. The strong dependence of absolute recovered permeability on wet accumulated solids (WACS) concentration, or clogging propensity, revealed clogging to deleteriously affect membrane permeability decline and recovery (from mechanical declogging and chemical cleaning), with WACS levels increasing with increasing MLSS. Evidence from the study indicated clogging may permanently reduce membrane permeability post declogging and chemical cleaning, corroborating previously reported findings.

Phosphorus removal in a membrane-assisted BNR process with focus on evolutions of PAOs and DPAOs

A bench-scale UCT (University of Cape Town)-type membrane bioreactor (UCT-MBR) fed with low-strength synthetic wastewater was operated to investigate phosphorus removal with reference to poly-phosphate accumulating organisms (PAOs) and denitrifying poly-phosphate accumulating organisms (DPAOs). A series of kinetic assays of PAOs and DPAOs were also conducted to analyze the metabolic activities of PAOs and DPAOs. Results showed that 93% of chemical oxygen demand (COD) and 77% of total nitrogen could be removed at 0.08 kgCOD kg(-1) MLSS d(-1) and 0.015 kgN kg(-1) MLSS d(-1) loading (MLSS: mixed liquor suspended solids). Removal efficiencies of total phosphorus increased during the experimental phase, with an ultimate removal efficiency of 96.1%. Kano and Kaer increased from 1.95 and 6.29 mgPO4(3-)-P g(-1) MLSS h(-1) to 5.47 and 11.13 mgPO4(3-)-P g(-1) MLSS h(-1) for DPAOs and PAOs respectively, with the increased ratio of DPAOs to PAOs from 31 to 49% implying DPAO metabolic activity increased faster than that of PAOs during the DPAO accumulation phase. Pano-uptake increased by 6.6 mg L(-1) and the ratio of PTano-uptake to PTupt increased from 58.97 to 91.62%. The ratio of DPAOs to PAOs tended to stabilize at around 50% over time.

Discretization of electronic states in large InAsP/InP multilevel quantum dots probed by scanning tunneling spectroscopy

The topography and the electronic structure of InAsP/InP quantum dots are probed by cross-sectional scanning tunneling microscopy and spectroscopy. The study of the local density of states in such large quantum dots confirms the discrete nature of the electronic levels whose wave functions are measured by differential conductivity mapping. Because of their large dimensions, the energy separation between the discrete electronic levels is low, allowing for quantization in both the lateral and growth directions as well as the observation of the harmonicity of the dot lateral potential.

Cytogenetic effects induced by accelerated carbon ions with shielding

Our work aims to understand the effects of shielding on the induction of biological damage by heavy charged particles and to compare the shielding effects of different materials at the same LET from two aspects: the biological effectiveness including or not including secondary particles emitted at large angles and the biological effectiveness at different angles with respect to the beam direction. We designed and conducted biological experiments to determine the biological effectiveness of 200 MeV/u carbon ions after traversing different shielding materials (Lucite and aluminium). Whole blood samples, which were either attached to the shielding material (48 mm Lucite or 29 mm aluminium)or positioned at 300 cm away from it at different angles with respect to the beam axis, were exposed to carbon ion beams. For comparison, whole blood samples were exposed directly to 200 MeV/u carbon ions. Chromosomal aberrations in lymphocytes were scored. The results indicated that the biological effectiveness per unit dose was not significantly changed by 48 mm Lucite or 29 mm aluminium, and no significant differences were observed in lymphocytes attached to the target and in lymphocytes positioned at a distance of 300 cm away from the target, at 0º angle of the beam axis. However, when plotted as a function of the number of ions hitting the shielding target, the curves are separated and the shield increases the effectiveness per unit ion. The frequency of chromosomal aberrations at tilted angles behind 29 mm Al and 48 mm Lucite was almost the same. These lesions were considered to be caused by secondary particles due to the passage of particles through the shielding materials.

Improvement of the immunity of pig to Hog cholera vaccine by recombinant plasmid with porcine interleukin-6 gene and CpG motifs

In order to observe the dosage-effect of recombinant pig interleukin-6 gene and CpG motifs on the immune responses of swine to vaccine, a novel recombinant eukaryotic VPIL6C plasmid was packed with chitosan nanoparticles (CNP) prepared by ionic cross linkage, which contains pig interleukin-6 gene and immunostimulatory sequence consisted of 11 CpG motifs. CNP-VRIL6C was then utilized to inoculate 30-day-old piglets intramuscularly at the dosage of 0.5, 1.0 and 1.5mg/per capita, respectively. Meanwhile, the piglets were injected with attenuated classical Hog cholera vaccine and designated as A1, A2 and A3 group. The blood was weekly collected from the piglets after vaccination to detect the changes of immunoglobulins, specific antibody, interleukins, IFN-γ and immune cells. The results were found that compared to those of the control piglets injected with VR1020-CNP, the content of IgG, IgA and IgM, specific antibodies, IL-2, IL-6 and IFN-γ significantly increased in the sera from the treated three groups from 14 to 70 days after vaccination (P<0.05); the number of T(H), T(C) and CD3(+) positive T cells raised obviously in the blood of VPIL6C treated piglets (P<0.05). Also the above immune indexes of A1 group were significantly lower to different extent in comparison with those of A2 and A3 group from 14 to 56 days post inoculation (P>0.05). Moreover, the lymphocytes also remarkably elevated in the treated groups (P<0.05). These indicate that VPIL6C entrapped with CNP is a novel effective adjuvant to boost the humoral and cellular immunity of pig to Hog cholera, implying it's potentiality to enhance the resistance of pig against infectious diseases.

Comparison of biological activated carbon (BAC) and membrane bioreactor (MBR) for pollutants removal in drinking water treatment

Biological activated carbon (BAC) and membrane bioreactor (MBR) were systematically compared for the drinking water treatment from slightly polluted raw water under the same hydraulic retention time (HRT) of 0.5 h. MBR exhibited excellent turbidity removal capacity due to the separation of the membrane; while only 60% of influent turbidity was intercepted by BAC. Perfect nitrification was achieved by MBR with the 89% reduction in ammonia; by contrast, BAC only eliminated a moderate amount of influent ammonia (by 54.5%). However, BAC was able to remove more dissolved organic matter (DOM, especially for organic molecules of 3,000 approximately 500 Daltons) and corresponding disinfection by-product formation potential (DBPFP) in raw water than MBR. Unfortunately, particulate organic matter (POM) was detected in the BAC effluent. On the other hand, BAC and MBR displayed essentially the same capacity for biodegradable organic matter (BOM) removal. Fractionation of DOM showed that the removal efficiencies of hydrophobic neutrals, hydrophobic acids, weakly hydrophobic acids and hydrophilic organic matter through BAC treatment were 11.7%, 8.8%, 13.9% and 4.8% higher than that through MBR; while MBR achieved 13.8% higher hydrophobic bases removal as compared with BAC.

STM images of subsurface Mn atoms in GaAs: evidence of hybridization of surface and impurity states

We show that scanning tunneling microscopy (STM) images of subsurface Mn atoms in GaAs are formed by hybridization of the impurity state with intrinsic surface states. They cannot be interpreted in terms of bulk-impurity wave-function imaging. Atomic-resolution images obtained using a low-temperature apparatus are compared with advanced, parameter-free tight-binding simulations accounting for both the buckled (110) surface and vacuum electronic properties. Splitting of the acceptor state due to buckling is shown to play a prominent role.