[Curative effect of percutaneous microwave ablation therapy on hepatocellular carcinoma survival: a 15-year real-world study]

Objective: To evaluate the long-term efficacy of percutaneous microwave ablation (MWA) therapy for hepatocellular carcinoma. Methods: 2054 cases with Barcelona Clinic Liver Cancer (BCLC) stage 0~B at the Fifth Medical Center of the Chinese People's Liberation Army General Hospital from January 2006 to September 2020 were retrospectively collected. All patients were followed up for at least 2 years. The primary endpoint of overall survival and secondary endpoints (tumor-related survival, disease-free survival, and postoperative complications) of patients treated with ultrasound-guided percutaneous MWA were analyzed. Kaplan-Meier method was used for stratified survival rate analysis. Fine-and-Gray competing risk model was used to analyze overall survival. Results: A total of 5 503 HCC nodules [mean tumor diameter (2.6±1.6) cm] underwent 3 908 MWAs between January 2006 and September 2020, with a median follow-up time of 45.6 (24.0 -79.2) months.The technical effectiveness rate of 5 375 tumor nodules was 97.5%. The overall survival rates at 5, 10, and 15-years were 61.6%, 38.8%, and 27.0%, respectively. The tumor-specific survival rates were 67.1%, 47.2%, and 37.7%, respectively. The free tumor survival rates were 25.8%, 15.7%, and 9.9%, respectively. The incidence rate of severe complications was 2.8% (108/3 908). Further analysis showed that the technical effectiveness and survival rate over the passing three time periods from January 2006-2010, 2011-2015, and 2016-September 2020 were significantly increased, with P < 0.001, especially for liver cancer 3.1~5.0 cm (P < 0.001). Conclusion: Microwave ablation therapy is a safe and effective method for BCLC stage 0-B, with significantly enhanced technical efficacy and survival rate over time.

[Spatial distribution pattern of local tumor progression analysis after microwave ablation of hepatocellular carcinoma based on three-dimensional magnetic resonance imaging]

Objective: To investigate the spatial distribution pattern of local tumor progression (LTP) for hepatocellular carcinoma (HCC) ≤5 cm after microwave ablation. Methods: A retrospective analysis was performed on 169 HCCs with matched MRI before and after ablation from December 2009 to December 2019. A tumor MRI was reconstructed using three-dimensional visualization technology. LTP was classified as contact or non-contact, early or late stage, according to whether LTP was in contact with the edge of the ablation zone and the occurrence time (24 months). The tumor-surrounded area was divided into eight quadrants by using the eight-quadrant map method. An analysis was conducted on the spatial correlation between the quadrant where the ablative margin (AM) safety boundary was located and the quadrant where different types of LTP occurred. The t-test, or rank-sum test, was used for the measurement data. 2-test for count data was used to compare the difference between the two groups. Results: The AM quadrant had a distribution of 54.4% LTP, 64.2% early LTP stage, and 69.1% contact LTP, suggesting this quadrant was much more concentrated than the other quadrants (P < 0.001). Additionally, the AM quadrant had only 15.2% of non-contact type LTP and 17.1% of late LTP, which was not significantly different from the average distribution probability of 12.5% (100/8%) among the eight quadrants (P = 0.667, 0.743). 46.6% of early contact type LTP was located at the ablation needle tip, 25.2% at the body, and 28.1% at the caudal, while the location distribution probabilities of non-early contact LTP were 34.8%, 31.8%, and 33.3%, respectively. Conclusion: LTP mostly occurs in areas where the ablation safety boundary is the shortest. However, non-contact LTP and late LTP stages exhibit the feature of uniform distribution. Thus, this type of LPT may result from an inadequate non-ablation safety boundary.

[Safety and efficacy of dual guiding catheter kissing technique in the treatment of stent partially dislodgement in coronary artery]

Objective: To investigate the safety and efficacy of dual guiding catheter kissing technique (DCK) in the treatment of stent partly dislodgement in coronary artery. Methods: The study retrospectively involved 6 hospitalized patients with coronary artery stent partly dislodgement during PCI at The First Affiliated Hospital of Zhengzhou University from February 2016 to June 2019, DCK was used in these patients. We observe the success rate of stent retrieval, success rate of PCI, incidence of complications and major adverse cardiovascular events in 1 year follow up. Results: 6 patients were involved, of which 3 are male, ages range 49 to 68 years old, 4 patients are diagnosed with unstable angina, the other two are stable angina. All the partially disloged stents in the 6 patients were successfully removed from coronary artery. Except for 1 patient who refused coronary artery stenting again, the other 5 patients were successfully implanted coronary artery stenting. No serious complications occurred, no patients died and no major adverse cardiovascular events happened during 1 year follow up. Conclusions: DCK is safe and effective to remove partially dislodged stent in coronary artery.

[Analysis of clinical features and prognosis of acute severe autoimmune hepatitis]

Objective: To analyze the clinical features and prognosis of acute severe autoimmune hepatitis (AIH). Methods: A retrospective analysis of the clinical data of patients with acute severe AIH admitted to our hospital from 2008 to 2019 was divided into acute AIH (A-AIH) and chronic acute AIH (AC-AIH) according to the presence or absence of liver diseases. Patients' general condition, liver biochemistry, immunology, histological features of liver, hormonal therapies prognosis and related factors were analyzed. Results: A total of 41 cases [39 females, age (54.24 ± 10.55) years] were collected. Alanine aminotransferase (ALT) and total bilirubin (TBil) were significantly increased, and the international normalized ratio (INR) was > 1.5. Acute lobular inflammation was the feature of acute and severe AIH in the histology of liver. The serum IgG level was (28.36 ± 8.35) g / L. The positive rate of antinuclear antibody (ANA) and anti-smooth muscle antibody (ASMA) was 82.9%, and 17.1%, respectively. Over 70% of acute severe AIHs were AC-AIH. The duration of onset of AC-AIH was > 8 weeks, while most A-AIHs < 8 weeks, and the differences between the two groups were statistically significant (P = 0.001). The mortality rate within 30 days after hormonal treatment was 19.5%. There were statistically significant differences in TBil, Model for End-Stage Liver Disease (MELD) score and leukocyte count between the death and survival group. Conclusion: The mortality rate in acute severe AIH is high, and most of them have the basis of chronic liver disease. Serum IgG level, autoantibodies and acute lobular inflammation are important factors for diagnosis. The prognosis of hormonal therapy is related to the patients' condition and course of disease.

Plasma metabolomics in perioperative period of defect repair in patients with pulmonary arterial hypertension associated with congenital heart disease

Background

The pathophysiological alterations in response to shunt correction in patients with pulmonary arterial hypertension associated with congenital heart disease (CHD-PAH) is still not clear.

Purpose

To explore the dynamic plasma metabolite profiling and its relationship with clinical characteristics in patients with CHD-PAH during the perioperative period of defect repair.

Methods

Plasma samples from 13 patients with CHD-PAH were harvested at four time points: before cardiopulmonary bypass (CPB) after anesthesia (Pre), immediately after CPB (T0), 24 h (T24), and 48 h (T48) after defect repair. The untargeted metabolomics strategy based on UPLC Q-TOF MS was used to detect the metabolites. Clinical measures were recorded at indicated time points.

Results

The sample distribution at four time points was well separated (Figure 1A, B). 193 metabolites were distinguished at different time points according to Variable Important in Projection (VIP) score (Figure 1C), enriched in pathways such as carnitine synthesis, phospholipid biosynthesis and oxidation of branched chain fatty acids (Figure 2A). 17 metabolites alterations were significantly correlated with gradients in mean pulmonary arterial pressure (mPAP) at T48 versus Pre, indicative of the response to defect correction (Figure 2B). Intriguingly, 4 out of the 17 (23.5%) metabolites including propionylcarnitine, butenylcarnitine, isobutyryl-L-carnitine and hexanoylcarnitine were enriched in oxidation of branched chain fatty acids. They were increased at both T24 and T48 (all P&lt;0.05 except propionylcarnitine with P&lt;0.05 at T24) (Figure 2C).

Conclusions

This is the first study to show the altered metabolic profiles of CHD-PAH patients in perioperative period of defect repair. Metabolites that respond to shunt correction could be a suitable non-invasive marker and would be of great value in disease monitoring and evaluating future therapeutic interventions.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): 13th Five-Year Plan–Precise Medicine–Key Research and Development Program–Clinical Cohort of Rare Disease; National Natural Science Foundation of China Figure 1. Overall analysis of metabolitesFigure 2. Shunt correction associated metabolites

[A multicenter retrospective study on the etiology of necrotizing pneumonia in children]

Objective: To investigate the etiology of necrotizing pneumonia (NP) in children and the clinical characteristics of NP caused by different pathogens in China. Methods: A retrospective, case-control study was performed in children with NP who were admitted to 13 hospitals in China from January 2008 to December 2019. The demographic and clinical information, laboratory data, etiological and radiological findings were analyzed. The data were divided into three groups based on the following years: 2008-2011, 2012-2015 and 2016-2019, and the distribution characteristics of the pathogens in different period were compared. Meanwhile, the pathogens of pediatric NP in the southern and northern China were compared. And the clinical characteristics of the Mycoplasma pneumoniae (MP) NP and the bacterial NP were also compared. T-test or Mann-Whitney nonparametric test was used for comparison of numerical variables, and χ² test was used for categorical variables. Results: A total of 494 children with NP were enrolled, the median ages were 4.7 (0.1-15.3) years, including 272 boys and 222 girls. Among these patients, pathogens were identified in 347 cases and the pathogen was unclear in the remaining 147 cases. The main pathogens were MP (238 cases), Streptococcus pneumoniae (SP) (61 cases), Staphylococcus aureus (SA) (51 cases), Pseudomonas aeruginosa (13 cases), Haemophilus influenzae (10 cases), adenovirus (10 cases), and influenza virus A (7 cases), respectively. MP was the most common pathogen in all three periods and the proportion increased yearly. The proportion of MP in 2016-2019 was significantly higher than that in 2012-2015 (52.1% (197/378) vs. 36.8% (32/87), χ²=6.654, P=0.010), while there was no significant difference in the proportion of MP in 2012-2015 and that in 2008-2011 (36.8% (32/87) vs. 31.0% (9/29), χ²=0.314, P=0.575).Regarding the regional distribution, 342 cases were in the southern China and 152 in the northern China. Also, MP was the most common pathogen in both regions, but the proportion of MP was higher and the proportion of SP was lower in the north than those in the south (60.5% (92/152) vs. 42.7% (146/342), χ²=13.409, P<0.010; 7.9% (12/152) vs. 14.3% (49/342), χ²=4.023, P=0.045). Comparing the clinical characteristics of different pathogens, we found that fever and cough were the common symptoms in both single MP and single bacterial groups, but chest pain was more common (17.0% (34/200) vs. 6.1% (6/98), χ²=6.697, P=0.010) while shortness of breath and wheezing were less common in MP group (16.0% (32/200) vs. 60.2% (59/98), χ²=60.688, P<0.01; 4.5% (9/200) vs. 21.4% (21/98), χ²=20.819, P<0.01, respectively). The white blood cell count, C-reactive protein and procalcitonin in the bacterial group were significantly higher than those in the MP group (14.7 (1.0-67.1)×10⁹/L vs. 10.5 (2.5-32.2)×10⁹/L, 122.5 (0.5-277.3) mg/L vs. 51.4 (0.5-200.0) g/L, 2.13 (0.05-100.00) μg/L vs. 0.24 (0.01-18.85) μg/L, Z=-3.719, -5.901 and -7.765, all P<0.01). Conclusions: The prevalence of pediatric NP in China shows an increasing trend during the past years. MP, SP and SA are the main pathogens of NP, and the most common clinical symptoms are fever and cough. The WBC count, C-reactive protein and procalcitonin in bacterial NP are significantly higher than those caused by MP.

Insulin-Like Growth Factor Binding Protein 5: an Important Regulator of Early Osteogenic Differentiation of hMSCs

Insulin-like growth factor binding protein 5 (IGFBP5) is broadly bioactive, but its role in osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hMSCs) remains to be clarified. Here, we demonstrated that IGFBP5 expression was markedly increased during the early osteogenic differentiation of hMSCs. We then over-expressed and knocked down this gene in hMSCs and evaluated the impact of manipulation of IGFBP5 expression on osteogenic differentiation based upon functional assays, ALP staining, and expression of osteogenic markers. Together, these analyses revealed that IGFBP5 over-expression enhanced early osteogenic differentiation, as evidenced by increased ALP staining and osteogenic marker induction, whereas knocking down this gene impaired the osteogenic process. Over-expression of IGFBP5 also markedly bolstered the extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation level, while IGFBP5 knockdown suppressed this signalling activity. We additionally compared the impact of simultaneous IGFBP5 overexpression and ERK1/2 inhibitor treatment to the effect of IGFBP5 over-expression alone in these hMSCs, revealing that small molecule-mediated EKR1/2 inhibition was sufficient to impair osteogenic differentiation in the context of elevated IGFBP5 levels. These findings indicated that IGFBP5 drives the early osteogenic differentiation of hMSCs via the ERK1/2 signalling pathway. Our results offer value as a foundation for future efforts to study and treat serious bone-related diseases including osteoporosis.

Constraining the External Capture to the ^{16}O Ground State and the E2 S Factor of the ^{12}C(α,γ)^{16}O Reaction

The ^{12}C(α,γ)^{16}O reaction is one of the most crucial reactions in nuclear astrophysics. The E2 external capture to the ^{16}O ground state (GS) has not been emphasized in previous analyses but may make a significant contribution to the ^{12}C(α,γ)^{16}O cross section depending on the value of the GS asymptotic normalization coefficient (ANC). In the present work, we determine this ANC to be 337±45  fm^{-1/2} through the ^{12}C(^{11}B,^{7}Li)^{16}O reaction using a high-precision magnetic spectrograph. This sheds light on the existing large discrepancy of more than 2 orders of magnitude between the previously reported ANC values. Based on the new ANC, we experimentally constrain the GS external capture and show that through interference with the high energy tail of the 2^{+} subthreshold state, a substantial enhancement in the GS S_{E2}(300) factor can be obtained (70±7  keV b) compared to that of a recent review (45 keV b), resulting in an increase of the total S factor from 140 to 162 keV b, which is now in good agreement with the value obtained by reproducing supernova nucleosynthesis calculations with the solar-system abundances. This work emphasizes that the external capture contribution for the ground state transition cannot be neglected in future analyses of the ^{12}C(α,γ)^{16}O reaction.

[Spatial-temporal cluster of hemorrhagic fever with renal syndrome in Hebei province, 2005-2016]

Objective: To explore the spatial-temporal distribution and epidemic characteristics of hemorrhagic fever with renal syndrome (HFRS) in Hebei province from 2005 to 2016. Methods: Records of HFRS cases reported from each county in Hebei during January 2005 to December 2016 were collected from National Notifiable Disease Surveillance System (NNDSS). Global and local spatial association statistics were used to measure the spatial autocorrelation and software GeoDa 1.2.0. Software SaTScan 9.4.1 was used to analyze spatiotemporal clusters. Software ArcGIS 10.2 was used to visualize the yearly scan results. Results: In Hebei province, a total of 8 437 human HFRS cases reported from 170 counties with an annual incidence rate of 0.99/100 000 population during 2005-2016. The peak incidence season was spring. Global spatial autocorrelation analysis on the incidence of HFRS at county-level showed that the value of Moran's I were all above 0 (P<0.05), indicating that the significant spatial cluster. The result of local indicators on spatial association (LISA) analysis revealed that identified hot spots were mainly in northeastern area, while cold spots were found in some counties of central and southern areas. Spatial-temporal scan detected that the primary cluster of HFRS incidence was mainly distributed in Qinhuangdao city and Tangshan city, including 11 counties (city/district): Beidaihe district, Haigang district, Funing district, Shanhaiguan district, Changli county, Lulong county and Qinglong Manchu autonomous county in Qinhuangdao city, and Qian'an city, Laoting county, Luanzhou city and Luannan county in Tangshan city (RR=39.64, P<0.001), during January-July in 2005. Conclusions: There were significant spatial-temporal cluster of HFRS in Hebei from 2005 to 2016. The cluster areas of HFRS were mainly in northeastern Hebei, it is necessary to strengthen the prevention and control programs of HFRS in these areas.

[Outcomes of patients treated with drug-coated balloons for de novo large coronary vessels]

Objective: To evaluate the efficacy and safety of drug-coated balloons (DCB) for de novo large coronary vessels. Methods: One hundred and two patients were retrospectively enrolled in this study, there were 104 lesions with the reference lumen diameter of target vessel more than 2.8 mm and patients were treated with DCB in de novo lesions during May 2015 and July 2017 in our center. Coronary artery angiography and quantitative coronary angiography were performed in 82 (80.4%) patients at follow up period ((8.1±1.7) months post procedure). The endpoints were late lumen loss (LLL) at follow up,and major adverse cardiac events (MACE) including cardiac death, myocardial infarction (MI), target lesion revascularization (TLR) and stent or target lesion thrombosis at 12 months post procedure. Results: Ninety-eight lesions were treated with DCB only, 6 (5.9%) bailout drug-eluting stent (DES) were used because of severe coronary dissection, 2 patients (2.0%) received revascularization driven by acute ischemic events during hospitalization. Cutting balloons and NSE balloons were used in 65.4% (68/104) and 26.0% (27/104) lesions. The lesion length was (12.57±3.58) mm and the DCB length was (19.87±4.55) mm. The late lumen loss was (0.01±0.52) mm during angiographic follow up. The TLR rate and overall MACE rate was 3.9% (4/102) and 3.9% (4/102) and there was no death,MI and target lesion thrombosis at 12 months follow up. Conclusion: DCB treatment for de novo large coronary vessels is effective and safe.

[Recent transmission of pulmonary tuberculosis and its influencing factors in Jing'an district, Shanghai, 2010-2015]

Objective: To understand the recent transmission of Mycobacterium tuberculosis (MTB), and to identify the influencing factors of recent transmission among pulmonary tuberculosis (TB) patients in Jing'an district, Shanghai. Methods: The genotypes and drug resistances of MTB isolated from TB patients registered in the TB designated hospitals in Jing'an district during 2010-2015 were analyzed through 12-loci Mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR)(QUB11b, QUB18, Mtub21, Miru26, QUB26, Mtub04, Miru31, Miru40, VNTR2372, VNTR3820, 3232, 4120), and tested for drug susceptibility as well. With the results of field epidemiological investigation, univariate and multivariate analyses were performed to analyze the distribution of the clusters and influencing factors on recent transmission. Results: This study enrolled 80 TB patients, 23 (28.75%) had a resistance to at least one anti-TB drug, and the prevalence of multidrug-resistant tuberculosis (MDR-TB) was 16.25%. A total of 65 genotypes were identified with 58 (72.50%, 58/80) being unique and 7 clusters with 2-10 isolated in each cluster. The proportion of clustering was 27.50% (22/80). Results from the multivariate analysis revealed that multidrug- resistance (OR=35.799, 95%CI: 4.239-302.346) and having comorbidity with TB (OR=7.695, 95%CI: 1.421-41.658) were independently associated with the clustering, which suggesting a recent transmission. The field investigation to the clustered cases proved that the patients in two clusters had epidemiological links, one was between family members, and the other contained 10 MDR-TB patients with 9 knowing each other which have a definite connection and 1 having the possible connection with them. Conclusion: Recent transmission of tuberculosis happened among TB patients in Jing'an district, with high risks among the MDR-TB patients.

[Antibiotic resistance analysis of Streptococcus pneumoniae isolates from the hospitalized children in Shanxi Children's Hospital from 2012 to 2014]

Objective: To investigate the antibiotic resistance status of Streptococcus pneumoniae isolates from hospitalized children in Shanxi Children's Hospital. Method: E-test and Kirby-Bauer methods were applied to determine drug sensitivity of the isolates collected from the body fluid specimens of hospitalized children in Shanxi Children's Hospital from January 2012 to December 2014. The antimicrobial sensitivity and minimum inhibitory concentration (MIC) of Streptococcus pneumoniae to the conventional antibiotics were analyzed, in order to compare the annual trends of non-invasive isolates, while the differentiation of sensitivity from specimens. The comparison of rates was performed by Chi-squared test and Fisher's exact test. Result: A total of 671 isolates of streptococcus pneumoniae were obtained, which could be divided as non-invasive isolates(607), invasive isolates from non-cerebrospinal fluid(non-CSF)(40) and invasive isolates from cerebrospinal fluid(CSF)(24). The antimicrobial sensitivity(isolates(%)) of the 671 isolates were respectively vancomycin 671(100.0%), linezolid 671(100.0%), levofloxacin 665(99.1%), penicillin 595(88.7%), ceftriaxone 516(76.9%), cefotaxime 512(76.3%), sulfamethoxazole-trimethoprin(SMZ-TMP) 103(15.4%), clindamycin 28(4.2%), tetracycline 26(3.9%), erythromycin 12(1.8%). From 2012 to 2014, the susceptibility rates of non-invasive isolates to penicillin every year were 95.0%(96/101), 97.3%(110/113), 87.3%(343/393), respectively, and there was significant difference among the three years(χ(2)=13.266, P<0.05), and the values of MIC(50, )MIC(90) and the maximum values of MIC(mg/L) of penicillin were 0.064, 2.000, 6.000 in 2012, which grew up to 1.000, 3.000, 16.000 in 2014. There was no significant difference in the susceptibility rate of non-invasive isolates to ceftriaxone and cefotaxime during these three years, (χ(2)=1.172, 1.198, both P>0.05). On the other hand, the values of MIC(50, )MIC(90) and the maximum value of MIC(mg/L) of ceftriaxone and cefotaxime both increased from 0.500, 2.000, 8.000 in 2012 to 0.750, 4.000, 32.000 in 2014. There was no significant difference in the susceptibility rate of non-invasive isolates to the rest antibiotic. Based on the same examining standard of CSF, the antimicrobial sensitivity(isolates(%)) of the non-invasive isolates to ceftriaxone, cefotaxime, SMZ-TMP were respectively 281(46.3%), 278(45.8%), 78(12.9%), were significantly lower than the susceptibility rate of the invasive isolates from non-CSF (28(70%), 28(70%), 14(35%), χ(2)=8.453, 8.817, 15.094, all P<0.012 5), and lower than the invasive isolates from CSF (18(75%), 18(75%), χ(2)=7.631, 7.905, P<0.012 5; 11(45.8%), P=0.001). The sensitivity of the isolates to the rest antibiotics were similar(P>0.05). Conclusion: More than 95.0% strains of the streptococcus pneumoniae isolates from the hospitalized children in Shanxi Children's Hospital were sensitive to vancomycin, linezolid, levofloxacin, and the susceptibility rate of penicillin, ceftriaxone, cefotaxime were 88.7%, 76.9%, 76.3%. However, less than 20.0% of streptococcus pneumoniae were sensitive to erythromycin, clindamycin, SMZ-TMP and tetracycline. The susceptibility rate of penicillin of non-invasive Streptococcus pneumoniae declined by these years, and the differences to ceftriaxone and cefotaxime can be neglected, but the values of MIC(50, )MIC(90) and the maximum value of MIC of all were linearly rising. The susceptibility rate of antibiotics to ceftriaxone and cefotaxime of the non-invasive isolates was lower than the invasive isolates.

Effect of phytosterols on rumen fermentation in vitro

We investigated the effect of phytosterols on rumen fermentation in vitro using gas syringes as incubators. Phytosterols were dissolved in ethyl acetate (8.3%) and added at various concentrations to the common diet in rumen fluid. In vitro gas production (GP) was recorded after 3, 6, 12, 18, and 24 h incubation. Incubation was stopped at 6, 12, and 24 h and the inoculants were then tested for pH, dry matter digestibility (DMD), microbial protein yield (MCP), lactic acid, NH3-N, and volatile fatty acids (VFAs). GP was consistently higher than the control; particularly, treatments at 12, 18, and 24 h reached extremely significant levels (P < 0.01). Compared to the control group, the pH of ruminal fluid was slightly lower after incubation, and DMD and MCP increased with increasing phytosterol level except for the content of MCP at 6 h, which changed only minimally. Lactate was significantly lower after treatment compared to the control at 12 h (P < 0.01) and 24 h (P < 0.05), while NH3-N at 12 h (P < 0.05) and 24 h (P < 0.01) after treatment decreased significantly. Acetate, propionate, butyrate, and total VFA for all treatments were higher than those of the control, particularly for butyrate at 6 h (P < 0.01). These results suggest that phytosterols modify rumen fermentation by inhibiting released harmful products and promoting the release of beneficial product, which may be useful for improving nutrient utilization and animal health.

Comparison study on qualitative and quantitative risk assessment methods for urban natural gas pipeline network

In this paper, a qualitative and a quantitative risk assessment methods for urban natural gas pipeline network are proposed. The qualitative method is comprised of an index system, which includes a causation index, an inherent risk index, a consequence index and their corresponding weights. The quantitative method consists of a probability assessment, a consequences analysis and a risk evaluation. The outcome of the qualitative method is a qualitative risk value, and for quantitative method the outcomes are individual risk and social risk. In comparison with previous research, the qualitative method proposed in this paper is particularly suitable for urban natural gas pipeline network, and the quantitative method takes different consequences of accidents into consideration, such as toxic gas diffusion, jet flame, fire ball combustion and UVCE. Two sample urban natural gas pipeline networks are used to demonstrate these two methods. It is indicated that both of the two methods can be applied to practical application, and the choice of the methods depends on the actual basic data of the gas pipelines and the precision requirements of risk assessment.

Mechanical compressive loading stimulates the activity of proximal region of human COL2A1 gene promoter in transfected chondrocytes

Previous studies have demonstrated that the mechanical compressive loading affects the biosynthesis of chondrocytes seeded in three dimensional scaffolds. In this study, the level of type II collagen mRNA expression was increased by a continuous dynamic compression at 10% compressive strain and 0.1 Hz in chondrocytes seeded in a biodegradable, elastomeric scaffold, poly(L-lactide-co-epsilon-caprolactone) (PLCL). To further examine this molecular mechanism, the promoter region of COL2A1 gene, which is encoding type II collagen, was analyzed using rabbit chondrocytes transfected with luciferase reporter vectors containing the 5'-flanking regions of human COL2A1 gene. A deletion mutant analysis revealed that the most active short promoter in response to continuous dynamic compression is in the region between -509 and -109 base pairs, where the transcription factor Sp1 is located. Additionally, an mRNA decay experiment using transcription inhibitor actinomycin D demonstrated that dynamic compression do not stabilize type II collagen mRNA. Our results indicate that mechanical compression increases the level of type II mRNA expression by transcriptional activation possibly through the Sp1 binding sites residing in the proximal region of the COL2A1 gene promoter.

Clinical study of Lipo PGE1-inhibiting platelet activation in acute rejection after kidney transplantation

To observe the efficacy of the platelet activation inhibitor Lipo PGE1 therapy in the recovery of graft function after an acute rejection episode after kidney transplantation. Forty patients with acute rejection after kidney transplantation were randomly assigned into groups treated with or without Lipo PGE1. The expression levels of CD61, CD63, and PAC-1 on platelet surfaces were assayed by flow cytometry. The recovery time for graft function and 1-year patient and graft survival rates were recorded. Compared with controls, the expression levels of CD61, CD63, and PAC-1 were lower among acute rejection patients who received Lipo PGE1 therapy. The recovery time for graft function was shorter and the 1-year patient and graft survival rates higher. Lipo PGE1 therapy in patients with acute rejection episodes may inhibit platelet activation thereby benefiting graft functional recovery. The 1-year survival rates of patients and grafts might be increased if the expression levels of CD61, CD63, and PAC-1 on the platelet surfaces was decreased by Lipo PGE1 therapy.

Relationship between the expression levels of CD61, CD63, and PAC-1 on platelet surface in peripheral blood and the transplanted kidney function

OBJECTIVE

To analyze the relationships between the expression levels of CD61, CD63, and PAC-1 on the platelet surface and the incidences of acute rejection and tubular necrosis as well as the recovery of graft function after renal transplantation.

METHODS

The expression levels of CD61, CD63, and PAC-1 on platelet surfaces were assayed by flow cytometry in 86 patients with different stages of uremia before and after transplantation. Patients were divided into three groups: 29 patients with normal graft function, 30 with acute rejection, and 27 with acute tubular necrosis. Patients with acute rejection were randomly assigned into groups treated with or without anticoagulants.

RESULTS

The expression levels of CD61, CD63, and PAC-1 on platelet surfaces significantly increased (P <.05) among patients with acute rejection, as compared with those with normal graft function or acute tubular necrosis. Compared with controls, the expression levels of CD61, CD63, and PAC-1 were lower among acute rejection patients who, received anticoagulant therapy. The recovery time for graft function shorter and, the 1-year patients and graft survival rates higher.

CONCLUSIONS

The pretransplant expression levels of CD61, CD63, and PAC-1 on platelet surface were significantly higher among patients with acute rejection, suggesting that this complication rather than acute tubular necrosis may be related to platelet activation. Patients with acute rejection displayed benefit from anticoagulant therapy.

Diagnosis of Liddle syndrome by genetic analysis of beta and gamma subunits of epithelial sodium channel--a report of five affected family members

OBJECTIVE

To screen the gene mutation in beta and gamma subunits of the epithelial sodium channel (ENaC) of a Chinese family, some of whose members are clinically diagnosed as suffering from Liddle syndrome.

METHODS

Twelve family members were recruited to the study. Among them, two brothers had been clinically diagnosed as suffering from Liddle syndrome. Peripheral blood samples were collected from all members of the family and total genomic DNA was prepared for genetic analysis. Polymerase chain reaction (PCR) was used for amplifying the last exon of beta (codon 513-673) and gamma (codon 503-632) subunits of the ENaC gene. PCR products were purified and subjected to a direct DNA sequence analysis.

RESULTS

Genetic analysis of the beta ENaC gene revealed a missense mutation of CCC to CTC at codon 616 in four middle-aged men of the second generation and one young woman of the third generation. There was no mutation of the gamma ENaC gene in any of the individuals examined.

CONCLUSION

Through direct DNA sequencing analysis, we diagnosed the disease present in five members of a Chinese family as Liddle syndrome, and excluded it in some other young offspring suffering from the monogenic disease. Our results provide further evidence that Pro616 is a critical amino acid that has a key role in the inhibition of sodium channel activity.

Localization of nAChR subunit mRNAs in the brain of Macaca mulatta

We present here a systematic mapping of nAChR subunit mRNAs in Macaca mulatta brain. A fragment, from the transmembrane segments MIII to MIV of Macaca neuronal nAChR subunits was cloned, and shown to exhibit high identity (around 95%) to the corresponding human subunits. Then, specific oligodeoxynucleotides were synthesized for in situ hybridization experiments. Both alpha4 and beta2 mRNA signals were widely distributed in the brain, being stronger in the thalamus and in the dopaminergic cells of the mesencephalon. Most brain nuclei displayed both alpha4 and beta2 signals with the exception of some basal ganglia regions and the reticular thalamic nucleus which were devoid of alpha4 signal. alpha6 and beta3 mRNA signals were selectively concentrated in the substantia nigra and the medial habenula. The strongest signals for alpha3 or beta4 mRNAs were found in the epithalamus (medial habenula and pineal gland), whereas there were no specific alpha3 or beta4 signals in mesencephalic dopaminergic nuclei. alpha5 and alpha7 mRNA signals were found in several brain areas, including cerebral cortex, thalamus and substantia nigra, although at a lower level than alpha4 and beta2. The distribution of alpha3, alpha4, alpha5, alpha6, alpha7, beta2, beta3 and beta4 subunit mRNAs in the monkey is substantially similar to that observed in rodent brain. Surprisingly, alpha2 mRNA signal was largely distributed in the Macaca brain, at levels comparable with those of alpha4 and beta2. This observation represents the main difference between rodent and Macaca subunit mRNA distribution and suggests that, besides alpha4beta2*, alpha2beta2* nAChRs constitute a main nAChR isoform in primate brain.

[Hypoxia induced increase of MDA and echinocytes from erythrocytes in rabbit's blood with special reference to inhibition of the increase by MPEG-SOD]

When rabbits acutely exposed to hypobaric hypoxia (at imitative altitude 5,000 m, PaO2 = 6.7 kPa), the percentage of the activity of superoxide dismutase (SOD in erythrocyte; EC 1.15.1.1) decreased respectively to 86%, 76%, 81%, 84%, 55%, 81%, 84% and 95% for a period of 0.25, 0.5, 1, 2, 3, 4, 5 and 24 h hypoxia while MDA (malondialdehyde) in erythrocyte and plasma increased significantly during hypoxia periods of 1, 2, 3, 5 and 24 h (n = 5, P < 0.05, P < 0.01 vs. normoxia group). The increase of MDA in plasma could be prevented by vitamin E (V. E, i.p, 1 mg daily for 3 consecative days before hypoxia), but that in erythrocyte did not show significant change probably because the injected V.E. without vehicle cannot penetrate through the erythrocyte membrane effectively. The echinocytes from erythrocytes increased significantly after hypoxia for 24 h (n = 5, P < 0.05 vs. normoxia group). However, by injecting MPEG-SOD (monomethoxypolythlene glycol-SOD) intravenously 30 min before hypoxia, the increase of MDA (both of erythrocyte and plasma) and echinocytes (from erythrocytes) were both inhibited obviously during hypoxia for 24 h (n = 5, P < 0.05, P < 0.01 vs. hypoxia group). It is inferred that the increase of MDA and echinocytes from erythrocytes may be due to lipid peroxidation by superoxide free radicals (O2-.) generated in erythrocytes through Fenton pattern Haber-Weiss reaction during hypobaric hypoxia.

[Acute hypoxia induce free radicals generation in rat's cortex and hippocampus]

Anesthetized rats were ventilated artificially to 10.5%-11.0% O2 in N2 (equivalent to altitude about 5 000 m). PBN (alpha-phenyl-ter-butylnitrone) was injected intravenously 5 min before hypoxia. The experiment results showed that the ESR (electron spin resonance) signal intensity of PBN-spin adduct in cortex and hippocampus both increased significantly during hypoxia (15 min) as compared with normoxia group (n = 5, P < 0.01). In the third group of rats injected with MPEG-SOD (monomethoxy-polyethylene glycol-superoxide dismutase) intravenously 20 min before hypoxia, the ESR signal intensity of PBN-spin adduct in cortex and hippocampus did not decrease significantly under hypoxia for 15 min (compared with hypoxia group, n = 5, P > 0.05). This may be due to the fact that MPEG-SOD could not pass the blood-brain barrier owing to its large molecular weight. The enzyme activity of SOD (superoxide dismutase. EC 1.15.1.1), GSH-Px (Glutathione peroxidase, EC 1.11.1.9) and content of MDA (malondialdehyde) was also determined. The results showed that the hypoxia had no effect on the SOD, GSH-Px activity and MDA content (n = 7 or n = 8, P > 0.05). The above results suggested that ventilation to 10.5%-11.0% O2 in N2 15 min induced free radical generation in rat's cortex and hippocampus, but this generation was not due to decrease of SOD, GSH-Px activity in cortex and hippocampus.

[8%-9% and 12%-13% hypoxic gas induced free radicals generation in rat's left and right myocardium]

Alpha-phenyl-tert-butylnitrone (PBN) was administered intravenously to capture free radicals of rat's myocardium. Rats were exposed to hypoxic gas (8%-9% O2 in N2) for 15 min. The ESR (electron spin resonance) signal intensity of PBN-spin adduct in the left myocardium increased significantly as compared with the normoxia group (n = 5, P < 0.05), but in the right myocardium there was no significant changes between hypoxia and normoxia. Rats exposed to hypoxic gas (12%-13% O2 in N2) were divided into four groups: I (hypoxia for 15 min), II (hypoxia for 60 min), III (hypoxia for 30 min/normoxia for 15 min/hypoxia for 30 min) and IV (injected MPEG- SOD intravenously before hypoxia for 60 min). The ESR signal intensity of PBN-spin adduct of left and right myocardium in group II increased significantly as compared with normoxia group (n = 5, P < 0.01), but the ESR signal intensity of group I didn't show obvious change as compared with normoxia group (n = 5, P > 0.05). In the right myocardium of group III the ESR signal intensity of PBN-spin adduct decreased significantly as compared with group II (n = 5, P < 0.05) and in the left myocardium did not decrease evidently. In the left myocardium of group IV the ESR signal intensity of PBN-spin adduct decreased evidently as compared with group II (n = 5, P < 0.05) and that in the right myocardium did not decrease evidently. When the rats were exposed to 8%-9% hypoxic gas for 15 min and 12%-13% hypoxic gas for 60 min, the SOD (superoxide dismutase, EC 1.11.1.9) activity of myocardium decreased and the content of MDA (malondialdehyde) increased significantly (n = 8, P < 0.05 or P < 0.01). The above results suggested that one way of myocardium free radical gereration may be relevant to decrease of SOD activity. The generation of free radicals pertained chiefly to superoxide free radical in the left myocardium and the membrane structure of myocardium cells might have been damaged largely during hypoxia.

[Epidermoid cysts of testicle: a report of 4 cases]

Epidermoid cysts of testicle is a kind of rare benign tumors of testicle, about 1% of all testicle tumors. In this paper, we described 4 cases of epidermoid cysts of testicle. Based on clinical manifestations, features of B-ultrasound, and other information, epidermoid cysts's histogenesis, pathology and classification were discussed. B-ultrasound is a powerful technique to derive a definite diagnosis before operation. Patients can be cured only by orchiectomy, and much attention should be paid to possible canceration.

[The protective effect of MPEG-SOD on the function of left ventricle during acute hypoxia]

Monomethoxypolyethylene glycol (MPEG) was attached covalently to superoxide dismutase (SOD, EC1.15.1.1). The molecular weight of MPEG-SOD was about 7.0 x 10(5) Dalton determined by Fast Protein Liquid Chromatography (FPLC with Sepharose 6 HR10/30). MPEG-SOD exhibited a sharply enhanced serum half life (more than 30 h) than that of the native SOD (6-10 min). To determine the role of MPEG-SOD in acute hypoxia-induced injury of left ventricular function, heart rate (HR), arterial pressure (AP), left ventricular pressure (LVP) and dp/dt (LV +/- dp/dtmax) were measured in male SD rats divided into three groups: Control group (n = 8, intravenously injected with physiological saline), native SOD group (n = 8,800 U SOD i. v.) and MPEG-SOD group (n = 9,800 U MPEG-SOD i. v.). LVP, LV +/- dp/dtmax, AP and HR showed no significant difference among these three groups before hypoxia. But in acute hypoxia simulating altitude of 6,000-6,500 m, LVP, LV+dp/dtmax and AP were decreased in the control group, while in MPEG-SOD group they were all increased compared with those in control group (P < 0.05, P < 0.01). There were no significant difference between control group and native SOD group. The results indicate that MPEG-SOD has a protective effect on the injury of myocardial function induced by acute hypoxia, and suggest that acute hypoxia cause increase of superoxide free radical (O2.-) and other derivative radicals damaging membrane system of the cell.

Clinical and laboratory observations on polysaccharide sulphate (PSS) in 282 cases of ischemic cerebrovascular disease

Polysaccharide sulphate (PSS) is a new heparinoid drug. The therapeutic effect and laboratory findings in the treatment of 282 cases with ischemic cerebrovascular disease by PSS were analysed in this study. In treating patients with acute cerebral infarction, the effective rate (93.2%) and highly effective rate (62.9%) were both significantly higher in comparison with controls. Excellent results were also obtained in treating patients with cerebral infarction at late and sequela stage and patients with transient ischemic attack. Laboratory observations and animal experiments showed that PSS has anticoagulative and vasodilatory effects. It can also reduce blood viscosity and serum lipids. So PSS is an effective drug for the prevention and treatment of ischemic cerebrovascular diseases.

[Clinical, laboratory and animal experimental observations in treating 288 cases of ischemic cerebrovascular disease with polysaccharide sulfate]

The therapeutic effect and laboratory finding in the treatment of 288 cases of ischemic cerebrovascular disease with PSS were analysed. Positive therapeutic response to PSS in this series of cases was obtained in 92.0% and 62.2% of the treated cases showed excellent results. Effects in the treated patients were better than in the controls. The laboratory findings showed that PSS had obvious anticoagulant effect and decreased blood viscosity and serum contents of lipids. The results of animal experiments showed that PSS had the action of blood dilution, lowering blood viscosity and ameliorating hypercoagulation. PSS was considered to be a prospective, useful drug to prevent and treat ischemic cerebrovascular disease.

[Study on follicle growth, ovulation and morphological changes of endometrium by ultrasonic and biochemical measurements]

Daily growth of the follicles before ovulation and the changes of the endometrium after ovulation were recorded in 16 spontaneous menstrual cycles by the ultrasonic and biochemical measurements. The mean diameter of the dominant follicle was 20 mm before ovulation, the mean volume 3.0 ml, and the growth rate of the follicles 1-3 mm/24 h. Ovulation occurred within 24 h of the luteinizing hormone peak and within 48 hours of the blood estrogen peak. The fact that the blood progesterone levels were higher on the day of the LH peak indicated that luteinization of the dominant follicles had already occurred prior to ovulation. Sonographic criteria of the endometrical tissue were obtained after the serial observation. According to the different sonographic appearances, the secretory phase of the endometrial tissue was divided into the early secretory phase, the middle secretory phase and the late secretory phase. The sonographic characterization of the endometrial tissue in the different phases as well as the thickness of the endometrium during the cycles were described. The clinical usefulness of the criteria of the different phases was to evaluate the subsequent luteal function, and facilitate the clinical management of the infertile women. The study confirms that ultrasound can provide a reliable measure in monitoring the follicular growth and ovulation, and observing the morphological changes of the endometrial tissue during the secretory phase. Thus the in vivo differentiation of the endometrial tissue during the secretory phase could be studied non-invasively by means of the ultrasound tissue characterization.

A follow-up study of the efficacy and safety of injectable microencapsulated megestrol acetate and a discussion on its contraceptive mechanism

A monthly injectable microencapsulated contraceptive was developed by the researchers of the School of Pharmacy of Sichuan Medical College, and a comparative clinical study was undertaken by the Sichuan Cooperative Research Group. It has been found that the microencapsulated compound consisting of 15 mg megestrol acetate and 5 mg estradiol valerate is associated with the lowest incidences of menstrual disturbances and other side effects. This is a follow-up report on the 434 women who used this 'optional' dosage of compound by before-and-after comparisons and by comparisons with two other groups of women: 41 women who were given the compound with the same dosage combination but with microencapsular coat dissolved, and 20-30 women who were using a non-steroidal contraceptive method such as IUDs, barrier or rhythm methods. The microencapsulated compound was highly effective in preventing accidental pregnancies. All except two of the 119 women who discontinued the medication experienced normal menstruation within 3 months. The study did not show changes in blood pressure, liver function, glucose tolerance level and plasma concentration of cholesterol in women using the compound. Cervical smears and breast examination also showed no evidence of epithelial abnormality or breast tumors. This new delivery system of microencapsulated injections affects the cervical mucus function, and inhibits ovulation as well as implantation of fertilized ovum.

Clinical evaluation of intramuscular injection of microencapsulated compound megestrol acetate

A comparative clinical study was undertaken by the Sichuan Cooperative Research Group for Microencapsulated Contraceptives to assess the efficacy of intramuscular microencapsulated megestrol compound as a long-acting contraceptive and to find the optimal dosage as regards efficacy, side effects and menstrual irregularities. Eight hundred twenty eight women were divided into four groups and injected monthly with four different dosage combinations that consisted of megestrol acetate and estradiol valerate. In all, 5298 dosage cycles were observed. The investigation indicated that microencapsulation effectively prolonged contraceptive effect of the short-acting agents, reduced the required dosage and lowered the incidence of side effects. A combination of 15 mg megestrol acetate and 5 mg estradiol valerate, as compared to the other three regimens, was found to be clinically most acceptable because of the lower incidence of menstrual irregularities.