[Three-dimensional volume rendering for dynamic characteristics of secundum atrial septal defect during various phases of the cardiac cycle and the impact on occluder selection]

Objective: To investigate the dynamic change of the secundum atrial septal defect (ASD) throughout the cardiac cycle, and assess its impact on occluder selection. Methods: This study retrospectively analyzed 35 patients with ASD who received electrocardiogram-gated coronary CT angiography (CCTA) throughout the cardiac cycle as well as interventional closure therapy in Fuwai Hospital from December 2016 to December 2019. The raw data were reconstructed into 20 phasic images of RR intervals (RRI) ranging from 0 to 95% in an increment of 5% and transmitted to a workstation for postprocessing. For each phase image, CT virtual endoscopy reconstruction technique (CTVE) was used to provide views of ASD. Axial sequence assisted CT volumetric measurement (CTAS) was used to calculate the maximum dimensions in axial planes (D_a) and in superior-inferior direction (D_b). Using a formula for converting circumference to diameter, the equivalent circle dimensions were calculated (D_e, D_e=minor axis+2 (major axis-minor axis)/3). Taking the data of 75% RRI phase, the patients were divided into D_a75%RRI≥D_b75%RRI group and D_a75%RRI<D_b75%RR group. According to the postoperative chest X-ray, the waist diameter of the occluder in the left anterior oblique plain film was measured, and its correction value (CR-POD_laoc) was calculated with the correction formula. Scatter plots of the changes of the mean values of D_a, D_b and D_e with the cardiac cycle were presented. The change and ratio of measured values of D_a and D_e at 35% and 75% RRI was calculated. The ratio of D_e change to D_a change in D_a75%RRI≥D_b75%RRI group and D_a75%RRI<D_b75%RR group was calculated, respectively, and compared between groups. Pearson correlation analysis was used to explore the correlation between CR-POD_laoc and D_e35%RRI and D_e75%RRI. Results: A total of 35 patients, aged (42.7±15.0) years, including 10 males, were included. Among 35 patients, 8 cases were divided into group D_a75%RRI≥D_b75%RRI and 27 cases into group D_a75%RRI<D_b75%RRI. Both D_a and D_b regularly changed at each phase throughout the cardiac cycle. The D_a changed significantly, with a maximum at phase of 35%-45% of RRI, and a minimum between phases of 90% and 0 of RRI. While the D_b showed insignificant changes during phases of 10%-90% RRI, and increased at 0-10% of RRI, then reduced in the remaining phases. The change of D_a was (6.35±2.46) mm, and the ratio of D_a values at 35% and 75% RRI was 0.77±0.08. The change of D_e was (2.28±1.32) mm, and the ratio of D_e at 35% and 75% RRI was 0.93±0.05. The ratio of D_e change to D_a change in the D_a75%RRI≥D_b75%RRI group was 0.67±0.13; while the ratio was 0.34±0.05 in D_a75%RRI<D_b75%RR group, and there was significant difference between the two groups (P=0.02). CR-POD_laoc was positively correlated with D_{e35% RRI} (r=0.99, P<0.001) and D_{e75% RRI} (r=0.98, P<0.001). Conclusions: Most secundum ASDs show oval shape with D_b>D_a. D_b is basically constant while D_a changes significantly during cardiac cycle (10%-90% RRI). Nonetheless, both values peak and maintain the maximum status at end-systolic phase (35%-45% RRI). For patients with huge ASD, occluder selection should be based on the D_e at 35% RRI phase, which is helpful for the successful intervention.

[Analysis of pathogen spectrum and antimicrobial resistance of pathogens associated with hospital-acquired infections collected from 11 teaching hospitals in 2018]

Objective: To investigate the spectrum and antimicrobial resistance of major pathogens causing nosocomial infections in China, 2018. Methods: Non-duplicated nosocomial cases as well as pathogens causing bloodstream infections (BSI), hospital-acquired pneumonia (HAP) and intra-abdominal infections (IAI) from 11 teaching hospitals across China were collected. The minimum inhibitory concentrations (MICs) of clinically significant strains were determined by agar dilution method or broth microdilution method. The Clinical and Laboratory Standards Institute (CLSI) M100-S29 criteria were used for interpretation, and the WHONET-5.6 software was used in data analysis. Results: A total of 1 590 cases were collected, including 831 cases from BSI, 450 cases from HAP and 309 cases from IAI. The most prevalent pathogens causing BSI were Escherichia coli (29.2%, 243/831), Klebsiella pneumoniae (16.2%, 135/831) and Staphylococcus aureus (10.1%, 84/831); the most prevalent pathogens causing IAI were E. coli (26.2%, 81/309), Enterococcus faecium (15.5%, 48/309) and K. pneumoniae (13.3%, 41/309); while Acinetobacter baumanii (24.7%, 111/450), Pseudomonas aeruginosa (20.7%, 93/450) and K. pneumoniae (16.2%, 73/450) were dominated in HAP. All S. aureus were susceptible to tigecycline, linezolid, daptomycin and glycopeptides; 77.8% (105/135) of S. aureus strains were susceptible to ceftaroline. Methicillin-resistant S. aureus (MRSA) accounted for 29.6% (40/135) of all the S. aureus, and was lower than the accounted rate of methicillin-resistant coagulase-negative Staphylococcus (MRCNS) (83.7%, 41/49). One E. faecium strain (1.1%, 1/95) resistant to vacomycin and teicoplanin and one E. faecalis strain (2.3%, 1/43) resistant to linezolid was found. The prevalence of extended-spectrum β-lactamase (ESBL) was 56.1% (193/344) in E. coli and 22.1% (55/249) in K. pneumonia; the rate of carbapenem resistant E. coli and K. pneumonia was 4.1% (14/344) and 22.9% (57/249), respectively; the percentage of ceftazidime/avibactam resistant E. coli and K. pneumonia was 2.3% (8/344) and 2.0% (5/249), respectively; the percentage of colistin resistant E. coli and K. pneumonia was 1.5% (5/344) and 7.6% (19/249), respectively; no E. coli and K. pneumonia strains were found resistant to tigecycline. The rate of carbapenem resistant A. baumanii and P. aeruginosa were 78.9% (146/185) and 36.7% (66/180), respectively. A. baumanii showed low susceptibility to the antimicrobial agents except colistin (99.5%, 184/185) and tigecycline (91.4%, 169/185). Colistin, amikacin and ceftazidime/avibactam demonstrated high antibacterial activity against P. aeruginosa with susceptility rate of 100% (180/180), 93.3% (168/180) and 85.6% (154/180), respectively. Conclusions: Nosocomial Gram-negative pathogens show high susceptibilities to tigecycline, colistin and ceftazidime/avibactam in vitro. Antimicrobial resistance in A. baumannii is a serious problem. The prevalence of carbapenem-resistant Enterobacteriaceae has increased, which should be monitored continuously in China.

Antitubercular Triazines: Optimization and Intrabacterial Metabolism

The triazine antitubercular JSF-2019 was of interest due to its in vitro efficacy and the nitro group shared with the clinically relevant delamanid and pretomanid. JSF-2019 undergoes activation requiring F420H2 and one or more nitroreductases in addition to Ddn. An intrabacterial drug metabolism (IBDM) platform was leveraged to demonstrate the system kinetics, evidencing formation of NO⋅ and a des-nitro metabolite. Structure-activity relationship studies focused on improving the solubility and mouse pharmacokinetic profile of JSF-2019 and culminated in JSF-2513, relying on the key introduction of a morpholine. Mechanistic studies with JSF-2019, JSF-2513, and other triazines stressed the significance of achieving potent in vitro efficacy via release of intrabacterial NO⋅ along with inhibition of InhA and, more generally, the FAS-II pathway. This study highlights the importance of probing IBDM and its potential to clarify mechanism of action, which in this case is a combination of NO⋅ release and InhA inhibition.

Intrabacterial Metabolism Obscures the Successful Prediction of an InhA Inhibitor of Mycobacterium tuberculosis

Tuberculosis, caused by Mycobacterium tuberculosis (M. tuberculosis), kills 1.6 million people annually. To bridge the gap between structure- and cell-based drug discovery strategies, we are pioneering a computer-aided discovery paradigm that merges structure-based virtual screening with ligand-based, machine learning methods trained with cell-based data. This approach successfully identified N-(3-methoxyphenyl)-7-nitrobenzo[c][1,2,5]oxadiazol-4-amine (JSF-2164) as an inhibitor of purified InhA with whole-cell efficacy versus in vitro cultured M. tuberculosis. When the intrabacterial drug metabolism (IBDM) platform was leveraged, mechanistic studies demonstrated that JSF-2164 underwent a rapid F₄₂₀H₂-dependent biotransformation within M. tuberculosis to afford intrabacterial nitric oxide and two amines, identified as JSF-3616 and JSF-3617. Thus, metabolism of JSF-2164 obscured the InhA inhibition phenotype within cultured M. tuberculosis. This study demonstrates a new docking/Bayesian computational strategy to combine cell- and target-based drug screening and the need to probe intrabacterial metabolism when clarifying the antitubercular mechanism of action.

[Comparison of disease activities and extent measurements for anti-neutrophil cytoplasmic autoantibody-associated vasculitis]

OBJECTIVE

To investigate the significance of a set of seven disease activities and extension measurements and their correlations between one and another for anti-neutrophil cytoplasmic autoantibody associated vasculitis (AAV).

METHODS

A total of 121 patients from Peking University International Hospital and Fouth Medical Center of PLA General Hospital with confirmed diagnoses of AAV clinically were enrolled in the study, including 15 cases of eosinophilic granulomatous with polyangiitis (EGPA), 59 cases of granulomatous with polyangiitis (GPA) and 47 cases of microscopic polyangiitis (MPA). A hundred and twenty-one AAV patients were divided into death group and survival group according to their survival conditions. A set of seven disease assessment scales including Birmingham vasculitis activity score (BVAS)-1994, BVAS-2003, as well as BVAS/GPA, vasculitis damage index (VDI), disease extent index (DEI), five factor score (FFS)-1996, and FFS-2009 were measured and scored one by one, and their relationships which were represented by Spearman correlation coefficient were compared between one and another.

RESULTS

BVAS-1994, BVAS-2003, as well as BVAS/GPA, VDI, DEI, and FFS, all of those seven evaluation indexes of the AAV patients in the death group were significantly higher than those in the survival group (P<0.05). Except for BVAS/GPA, all those above indicators in the patients with EGPA were lower than those in the patients with GPA and those in the patients with MPA, and those in all of the AAV patients as a whole group. There were high correlations among BVAS-2003, BVAS-1994 and BVAS/GPA (r values were 0.9 and 0.7, respectively); BVAS-1994 was fairly correlated with BVAS/GPA (r=0.69); FFS-1996 and FFS-2009 were highly correlated (r=0.73) with each other; BVAS-1994, BVAS-2003 and BVAS/GPA were fairly correlated with DEI (with r values of 0.62, 0.65, and 0.62, respectively); VDI was also fairly correlated with BVAS-1994 and with BVAS-2003 (r values were 0.49 and 0.52, respectively).

CONCLUSION

All of those seven AAV assessment indicators above can be used as indicators of disease activity and prognosis in AAV patients, most of which were relevant within one and another. There were high correlations among BVAS-2003, BVAS-1994 and BVAS/GPA, and besides, there were also high correlations between FFS-1996 and FFS-2009.

The clinical application of a novel method of internal fixation for femoral neck fractures-dynamic locking compression system

Background

Femoral neck fractures are the commonly encountered injury in orthopedic practice and result in significant morbidity and mortality. Currently, how to treat femoral neck fractures safely and effectively is still a challenge. The objective of this study is to evaluate the efficiency of dynamic compression locking system for femoral neck fractures.

Methods

This is a retrospective study conducted from May 2015 to October 2016. The study included 36 patients suffering from femoral neck fractures who underwent closed reduction and were fixed using dynamic compression locking system. All surgeries were performed by the same surgeon. The study was conducted by telephone and on-site follow-up. The Garden classification and anatomical site classification were categorized for all patients. We assessed radiographic outcomes of union, femoral neck shortening, screw back-out, and femoral head avascular necrosis. We also evaluated functional outcome using the Harris hip score. Other outcomes included the length of surgery, duration of hospital stay, injury to surgery time, intraoperative hemorrhage, time to clinical bone union, and other fracture complications.

Results

All patients were followed up 12 to 29 months with an average of 21.58 ± 5.41 months. All cases were caused by falls including 17 males and 19 females with an average age of 65.33 ± 9.30 years old ranging from 53 to 82 years old. Among them, injury to surgery time ranged between 1 and 4 days with an average of 2.58 ± 1.05 days. Duration of hospital stay was 8 to 21 days with an average of 15.33 ± 3.71 days. Intraoperative hemorrhage was 40 to 80 ml with an average of 61.67 ± 12.31 ml. Operation time was from 35 to 80 min with average of 50.25 ± 11.77 min. According to Garden classification, 9 cases (25%) were type II and 27 cases (75%) were type III. According to the anatomical site classification, 8 cases (22.2%) were subcapital femoral neck fractures, 19 cases (52.8%) trans-cervical, and 9 cases (25%) basi-cervical. At present, the follow-up has not found the fracture complications of femoral head avascular necrosis, fracture nonunion, and re-fracture. All patients achieved solid bone union. The mean time of clinical bone union was 3 to 4 months. Among all patients, there were only 3 cases of femoral neck shortening < 5 mm and 1 case of screw back-out = 4 mm. For Harris scoring, average Harris scale at the end of the follow-up was 93.42 ± 3.95 ranging from 85 to 98. There were 32 cases of excellent function scores on the Harris scale and 4 cases of good function scores on the Harris scale. Therefore, the excellent and good rate of Harris hip scores was 100%.

Conclusions

Femoral neck dynamic compression locking system for femoral neck fractures in elderly patients can provide effective stability and reduce complications and revision rates.

Diagnosis related group grouping study of senile cataract patients based on E-CHAID algorithm

AIM

To figure out the contributed factors of the hospitalization expenses of senile cataract patients (HECP) and build up an area-specified senile cataract diagnosis related group (DRG) of Shanghai thereby formulating the reference range of HECP and providing scientific basis for the fair use and supervision of the health care insurance fund.

METHODS

The data was collected from the first page of the medical records of 22 097 hospitalized patients from tertiary hospitals in Shanghai from 2010 to 2012 whose major diagnosis were senile cataract. Firstly, we analyzed the influence factors of HECP using univariate and multivariate analysis. DRG grouping was conducted according to the exhaustive Chi-squared automatic interaction detector (E-CHAID) model, using HECP as target variable. Finally we evaluated the grouping results using non-parametric test such as Kruskal-Wallis H test, RIV, CV, etc.

RESULTS

The 6 DRGs were established as well as criterion of HECP, using age, sex, type of surgery and whether complications/comorbidities occurred as the key variables of classification node of senile cataract cases.

CONCLUSION

The grouping of senile cataract cases based on E-CHAID algorithm is reasonable. And the criterion of HECP based on DRG can provide a feasible way of management in the fair use and supervision of medical insurance fund.

Addressing the Metabolic Stability of Antituberculars through Machine Learning

We present the first prospective application of our mouse liver microsomal (MLM) stability Bayesian model. CD117, an antitubercular thienopyrimidine tool compound that suffers from metabolic instability (MLM t_1/2 < 1 min), was utilized to assess the predictive power of our new MLM stability model. The S-substituent was removed, a set of commercial reagents was utilized to construct a virtual library of 411 analogues, and our MLM stability model was applied to prioritize 13 analogues for synthesis and biological profiling. In MLM stability assays, all 13 analogues had superior metabolic stability to the parent compound, and six new analogues had acceptable MLM t_1/2 values greater than or equal to 60 min. It is noteworthy that whole-cell efficacy and lack of relative mammalian cell cytotoxicity could not be predicted simultaneously. These results support the utility of our new MLM stability model in chemical tool and drug discovery optimization efforts.

[Clinical effect of vacuum sealing drainage in the treatment of complex fracture and dislocation of foot with severe soft tissue injury]

Objective: To observe the clinical effect of vacuum sealing drainage (VSD) in the treatment of complex fracture and dislocation of foot with severe soft tissue injury. Methods: From March 2012 to January 2015, a retrospective analysis of 108 cases of the foot closed complex fracture dislocation with severe soft tissue injury in Department of Foot and Ankle, the Second Hospital of Tangshan City, Tangshan.Injury mechanisms included press and crush injury, traffic accident.According to the operation the cases were divided into the VSD group (56 cases) and the control group (52 cases). The injury foot swelling after treated by open reduction and internal fixation or fusion joint fracture and dislocation. VSD technique was used to cover the wound and wound in group VSD. The wound was sutured, the sterile dressing was covered and the dressing was changed regularly in the control group. Results: Preoperative hospitalization time: 16 days in group VSD, 28 days in the control group; the total hospitalization time: 33 days in group VSD, 53 days in the control group; wound healing: 29 cases in VSD group, 12 cases in the control group; prolonged healing after dressing: 16 cases in VSD group, 13 cases in the control group; after skin grafting healing: 9 cases in VSD group, 17 cases in the control group; healed after flap transposition: 2 cases in VSD group and 10 cases in thecontrol group.The difference of the data of the two groups was statistically significant, P<0.05.Maryland foot score: 55-98 (average: 88.8, median: 91.5) points in VSD group, 38-97 (average: 84.85, median: 91) points in control group, compared with median by rank sum test, Z value: -2.755, the difference was statistically significant, P< 0.05.The late recovery effect rating: 39 casesexcellent, good 12 cases, can be 5 cases, no poor in VSD group, excellent 29 cases, good 8 cases, can be 11 cases, poor 4 cases in the the control group, the difference was statistically significant, P<0.05. Conclusion: VSD can shorten the preoperative waiting time and total hospitalization time, improve the wound healing rate directly, reduce the skin grafting and flap transfer replacement rate, reduce the secondary injury, increased fracture risk reduction and internal fixation, reduce joint fusion rate in the treatment of foot closed complex fracture and dislocation with severe soft tissue injury.

[The clinical analysis of 46 cases with antineutrophil cytoplasmic antibody-associated vasculitis]

OBJECTIVE

To investigate the clinical features of patients with antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV), and to explore the disease activity of AAV patients and the relationship with prognosis.

METHODS

The clinical data of 46 cases of AAV patients in the First Affiliated Hospital of PLA General Hospital were analyzed retrospectively.The clinical and laboratory features of each clinical subtype were compared.The disease activity of AAV and the relationship between disease activity and prognosis were evaluated.

RESULTS

Among the 46 patients with AAV, 24 were male, and 22 were female, with the average age of 56±18.Among the subtypes of AAV, the number of granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA) were 22, 17 and 4 respectively, while the positive rate of ANCA are 72.7%, 88.2% and 50.0% respectively.For GPA, the results of ANCA were mainly C-ANCA or ANCA directed toward proteinase-3 (PR3), and for MPA, the results of ANCA were mainly P-ANCA or ANCA directed toward myeloperoxidase (MPO). Upper and lower respiratory disease, renal involvement and non-deformity arthropathy were the common clinical manifestations of all primary AAV subtypes.Epistaxis, nasal blood scab, saddle nose, pulmonary nodule and intrapulmonary cavities were the characteristic manifestations of GPA, while rapid progress of renal failure was prominent in MPA.Whatever their ANCA results, there were no significant differences between each other as to system-organ involvements and laboratory indexes.Seven patients (15.2%) died during hospitalization or in follow-up visits.Serious involvements of heart, lung, kidney, and complicated with infections were the main risk factors of death in AAV patients.

CONCLUSIONS

Upper and lower respiratory involvements and kidney diseases are the primary manifestations of AAV patients.ANCA results are irrelevant with disease activity and system-organ involvements.Serious involvements of heart, lung, kidney, and complicated with infections are the main risk factors of death in AAV patients.

[Surgical treatment and curative effect observation of vascular malformations in the adult floor of the mouth and pharyngeal space]

Objective:To investigate the effect of surgical treatment of vascular malformation in the adult floor of the mouth and pharyngeal space. Method:Collect 12 cases of vascular malformation from the floor of the mouth and pharyngeal space.All of them were checked out of the different degrees of tongue elevation and dysphagia and to carry out the excision of vascular malformation with lingual nerve and hypoglossal nerve preservation. Result:The lesion reduction degree of 10 cases of patients were Ⅳ class(excellent), theoher 2 cases were Ⅲ class(good). Hematoma at the bottom of the mouth after operation were not happened. Follow-up 0.5-3 years,tongue deviation appeared in 1 cases of postoperation. After 6 months of follow-up, the tongue is in the middle when it put out, functional recovery,no tongue muscle atrophy,no tongue movement disorder in the rest of the patients,no obvious recurrence of vascular malformations, no swallowing disorder in all patients. Conclusion:It would be obtained ideal therapeutic effect with surgical treatment in the adult vascular malformations of the floor of the mouth and pharyngeal space.It would be the key to the success of surgery with protecting the lingual nerve and hypoglossal nerve and controlling bleeding.

[Epidemiological characteristics of dyslipidemia in remote rural areas of Xinjiang, 2009-2010]

Objective: This study aimed to estimate the prevalence of dyslipidemia, hypertriglyceridemia, hypercholesterolemia, high blood low density lipoprotein cholesterol (LDL-C), and low blood high density lipoprotein cholesterol (HDL-C) in remote rural areas of Xinjiang and analyze these indicators' epidemiological characteristics. Methods: A survey of 13 000 individuals (aged ≥18 years) was conducted using a four-stage cluster random sampling method in Jiashi, Xinyuan, Aheqi, and Shawan Counties, Xinjiang, in 2009-2010. After nonpermanent residents were excluded, 12 154 individuals were included in this study. Questionnaire and physical examinations were conducted, including collection of fasting blood to detect TG, TC, LDL-C, and HDL-C. The results were calculated after complex weighting and compared according to the prevalence of different gender and age groups. Results: The overall levels of TG, TC, LDL-C, and HDL-C were 1.34±1.09, 4.45±1.16, 2.36±0.86, and 1.37±0.58 mmol/L, respectively. After complex weighting, the overall prevalence of dyslipidemia was 35.4%; that among men (42.9%) was greater than that among women (29.5%; χ²=234.19, P<0.001), and the prevalence was 35.9%, 34.5%, and 35.1% (χ²=1.52, P=0.467) in participants aged 18-44, 45-59, and ≥60 years, respectively. The overall prevalence of hypertriglyceridemia was 11.4%; that among men (13.5%) was greater than that among women (9.8%; χ²= 40.72, P<0.001), and the prevalence was 9.6%, 13.0%, and 13.2% (χ²=38.71, P<0.001) in participants aged 18-44, 45-59, and ≥60 years, respectively. The prevalence of hypercholesterolemia was 5.7%; that among men(5.0%) was greater than that among women (6.2%; χ²=6.95, P=0.008), and the prevalence was 3.5%, 7.4%, and 8.4% (χ²=105.24, P<0.001) in participants aged 18-4, 45-59, and ≥60 years, respectively. The prevalence of high blood LDL-C was 2.8%, and there was no significant difference between men (3.0%) and women (2.4%; χ²=1.43, P=0.231); the prevalence was 3.5%, 7.4%, and 8.4% (χ²=42.81, P<0.001) in participants aged 18-44, 45-59, and ≥60 years, respectively. The prevalence of low blood HDL-C was 24.0%; that among men (31.6%) was greater than that among women (18.0%; χ²=304.02, P<0.001), and the prevalence was 27.8%, 20.6% and 19.5% (χ²=96.61, P<0.001) in participants aged 18-44, 45-59, and ≥ 60 years, respectively. Conclusions: Low blood HDL-C was the main type of dyslipidemia among the population in remote rural areas of Xinjiang. The prevalence of dyslipidemia among men was greater than that among women, and there was a trend of younger men than women showing dyslipidemia.

Effects of ginsenoside Rg1 on the senescence of vascular smooth muscle cells

The development of age-related cardiovascular disease is associated with the senescence of vascular cells. This study aimed to investigate the effect of ginsenoside Rg1 on vascular smooth muscle cell (VSMC) senescence. Primary VSMCs were cultured and divided into control, D-galactose (D-gal), Rg1-L, and Rg1-H groups, which were cultured without and with D-gal, and with low- and high-concentrations of Rg1, respectively. D-gal-induced cellular senescence was identified by b-galactosidase staining, and ultrastructural changes within the cells were observed. The expression of p16, p21, and p53 in the four groups of VSMCs was determined by western blotting, and the cell cycle was investigated by flow cytometry. Compared with the control group, there was an obvious change in the ultrastructure of VSMCs in the D-gal group, and the proportion of b-galactosidase-positive cells was significantly increased (P < 0.05). In addition, p16, p21, and p53 expression was significantly increased (P < 0.05) and the cell cycle was arrested in the G0/G1 phase. Compared with the D-gal group, the percentage of positive cells was significantly reduced (P < 0.05) in the Rg1 groups, the expression of p16, p21, and p53 was significantly reduced (P < 0.05), and the number of cells in the G0/G1 phase decreased (P < 0.05). Ginsenoside Rg1 can inhibit VSMC senescence, and the mechanisms may be related to its partial inhibition of the p16^INK4a/Rb and p53-p21^Cip1/Waf1 signaling pathways during the cell cycle.

[Association between CETP polymorphisms and haplotypes with dyslipidemia in Xinjiang Uygur and Kazak residents]

OBJECTIVE

To explore the relationship between the polymorphisms and haplotypes in the CETP gene and dyslipidemia among Xinjiang Kazak and Uygur residents.

METHODS

A population status survey was performed from 2010 to 2011 in Kashgar Xinjiang Uygur and Kazak residents, stratified cluster sampling method was used to select Uygur, Kazak residents with abnormal blood lipid values (n=367 and 345, respectively) as the dyslipidemia groups, and to select residents with normal lipid values as control group from the same area (n=374 and 390, respectively). SNaPshot technology was applied to detect the DNA of CETP gene rs3764261, rs1800775, rs708272 and rs5882 loci in all selected residents, and linkage disequilibrium analysis and haplotype construction were performed.

RESULTS

(1) In Uygur residents, the dyslipidemia risk of rs708272 CT (OR=0.64, 95%CI 0.46-0.91, P=0.01) and TT genotype (OR=0.60, 95%CI 0.40-0.91, P=0.02) was significantly lower than CC genotype. Dyslipidemia risk of rs3764261 GT (OR=0.55, 95%CI 0.40-0.74, P=0.00) and TT genotype (OR=0.47, 95%CI 0.28-0.78, P<0.01) was significantly lower than GG genetype. Dyslipidemia risk of the rs1800775 CC genotype was higher than AA genotype (OR=1.79, 95%CI 1.17-2.74, P=0.01). There was no statistical significance in CETP gene of the 4 genotype and allele frequency between the dyslipidemia and normal lipid groups in Kazak residents (all P>0.05). (2) In Uighur residents with dyslipidemia, HDL-C level was significantly higher in rs708272 TT genotype carriers than in CC and CT genotypes (all P<0.05) and in rs3764261 TT genotype carriers than in GG genotype carriers (P=0.008), while was significantly lower in rs1800775 CC genotype carriers with AA genotype carriers (P=0.008). (3) Linkage disequilibrium analysis showed that there was strong linkage disequilibrium between rs3764261 and rs708272 (D'=0.869, r(2)=0.869), rs1800775 and rs708272 (D'=0.845, r(2)=0.446) in Uighur residents, and there was strong linkage disequilibrium between rs3764261 and rs708272 (D'=0.963, r(2)=0.963), rs1800775 and rs708272 (D'=0.988, r(2)=0.630) in Kazak residents. (4) Significant differences were observed in frequency distribution of haplotype GACA(OR=0.579, 95%CI 0.388-0.864, P=0.006), GATA (OR=2.183, 95%CI 1.231-3.873, P=0.006), GCCA (OR=0.723, 95%CI 0.549-0.954, P=0.001), TATA (OR=0.723, 95%CI 0.549-0.954, P=0.021) and TATG (OR=0.601, 95%CI 0.429-0.841, P=0.002) in Uighur residents with normal or abnormal lipid profiles, while significant difference was observed in frequency distribution of haplotype GCCG (OR=1.961, 95%CI 1.207-3.188, P=0.005) in Kazak residents with normal or abnormal lipid profiles.

CONCLUSION

CETP genotype rs708272, rs3764261 and rs1800775 polymorphism is closely related to dyslipidemia and haplotype GACA, TATA and TATG will reduce the risk of dyslipidemia, while haplotype GATA, GCCA will increase the risk of dyslipidemia in Uygur residents. The four CETP polymorphisms are not related to the risk of dyslipidemia, but haplotype GCCG is related to increased risk of dyslipidemia in Kazakhs residents.

Association of APOA1 gene polymorphisms (rs670, rs5069, and rs2070665) with dyslipidemia in the Kazakhs of Xinjiang

The aim of this study was to investigate the potential association between apolipoprotein A1 (APOA1) gene rs670, rs5069, and rs2070665 polymorphisms and dyslipidemia in the Kazakh population of Xinjiang, China. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) was used to identify APOA1 (rs670, rs5069, and rs2070665) genotypes in 736 subjects (341 dyslipidemia patients and 395 control subjects). The frequencies of the CC genotype for rs1421085 were found to be 7.2% (obese group), 4.4% (overweight group), and 5.6% (control group). Polymorphisms of the three loci of the APOA1 gene in Kazakh subjects met Hardy-Weinberg equilibrium. The frequencies of the A allele for rs670 were found to be 14.3% (dyslipidemia group) and 12.7% (control group). The frequencies of the T allele for rs5069 and rs2070665 were: dyslipidmia group (7.2 and 30.1%, respectively) and control group (7.7 and 32.5%, respectively). Frequency distributions of the 3 types of genotypes and alleles of the three loci showed no statistically significant difference (P > 0.05). Significant differences were observed in lipoprotein (α) [Lp(α)] between patients with the rs2070665 CT + TT and CC genotypes (P < 0.05); however, none of the other relevant indicators differed significantly between the two genotypes. No significant association was identified between rs670 or rs5069 and the lipid-related metabolic indices assessed in the study. These findings indicate that the polymorphisms in the APOA1 gene (rs670, rs5069, and rs2070665) are not associated with dyslipidemia in the Kazakh population assessed in this study.

Association between polymorphisms of fat mass and obesity-associated gene and metabolic syndrome in Kazakh adults of Xinjiang, China

The aim of this study was to assess the association between three FTO polymorphisms (rs9939609, rs8057044, and rs1421085) and metabolic syndrome (MS)-related outcomes in the low-income, rural, nomadic minority Khazakh population in far western China. A total of 489 subjects (245 MS patients, 244 controls) were included in the study and DNA samples were genotyped for the three polymorphisms by matrix-assisted laser desorption/ionization time of flight mass spectrometry. The frequencies of the rs1421085 and rs9939609 genotypes and alleles did not differ significantly between MS patients and control, while the frequencies of rs8057044 G alleles and GG genotypes were higher in MS patients (P < 0.05) than in control subjects (G: 61.16 vs 53.53%, GG: 39.07 vs 29.05%) and the frequencies of rs8057044 A genotypes and alleles were lower (P < 0.05) in MS patients compared with controls (AA: 17.36 vs 21.99%, A: 38.84 vs 46.47%). Risk analysis of the rs8057044 polymorphism revealed individuals with GA and GG genotypes to have 1.112 and 1.731 times higher risks of developing MS than those with the AA genotype, respectively, while the G allele was found to be associated with a 1.367 times higher risk of developing MS compared with the A allele. These apparent correlations, however, did not hold true when adjusted for BMI. Weight, WC, HC, and BMI differed significantly between rs8057044 GG and AA+GA genotypes (P < 0.05).

Combining Metabolite-Based Pharmacophores with Bayesian Machine Learning Models for Mycobacterium tuberculosis Drug Discovery

Integrated computational approaches for Mycobacterium tuberculosis (Mtb) are useful to identify new molecules that could lead to future tuberculosis (TB) drugs. Our approach uses information derived from the TBCyc pathway and genome database, the Collaborative Drug Discovery TB database combined with 3D pharmacophores and dual event Bayesian models of whole-cell activity and lack of cytotoxicity. We have prioritized a large number of molecules that may act as mimics of substrates and metabolites in the TB metabolome. We computationally searched over 200,000 commercial molecules using 66 pharmacophores based on substrates and metabolites from Mtb and further filtering with Bayesian models. We ultimately tested 110 compounds in vitro that resulted in two compounds of interest, BAS 04912643 and BAS 00623753 (MIC of 2.5 and 5 μg/mL, respectively). These molecules were used as a starting point for hit-to-lead optimization. The most promising class proved to be the quinoxaline di-N-oxides, evidenced by transcriptional profiling to induce mRNA level perturbations most closely resembling known protonophores. One of these, SRI58 exhibited an MIC = 1.25 μg/mL versus Mtb and a CC₅₀ in Vero cells of >40 μg/mL, while featuring fair Caco-2 A-B permeability (2.3 x 10⁻⁶ cm/s), kinetic solubility (125 μM at pH 7.4 in PBS) and mouse metabolic stability (63.6% remaining after 1 h incubation with mouse liver microsomes). Despite demonstration of how a combined bioinformatics/cheminformatics approach afforded a small molecule with promising in vitro profiles, we found that SRI58 did not exhibit quantifiable blood levels in mice.

A Novel Allyl Transfer Coupled with a Grob Fragmentation

A novel acid-promoted rearrangement is disclosed. In the previously unknown transformation, an allyl group migrated to an in situ formed carbocation stabilized by an electron-rich aryl or heteroaryl group, resulting in a stereoselective intramolecular Grob fragmentation. The outcome of the rearrangement observed with an array of substrates can be satisfactorily rationalized using a working hypothesis with the aid of a six-membered transition state similar to those proposed for the anionic oxy-Cope or oxonia-Cope rearrangements, but involving only one instead of two double bonds.

Lutein alleviates arsenic-induced reproductive toxicity in male mice via Nrf2 signaling

This study aims to investigate the mechanisms involved in the action of lutein (LU) alleviating arsenic-induced reproductive toxicity using mice model. Forty male Kunming mice were received following treatments by gavage: normal saline solution (control), arsenic trioxide (ATO; 5 mg/kg/day), LU (40 mg/kg/day), and ATO + LU (5 mg/kg/day + 40 mg/kg/day). At the end, the mice were killed by cervical dislocation and weighed. Pathological examination was done on the testis. The biomedical parameters including superoxide dismutase (SOD), glutathione (GSH), total antioxidative capability, malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and reproductive indexes were analyzed. The messenger RNA (mRNA) and protein expression of Nrf2, heme oxygenase 1 (HO-1), glutathione S-transferase (GST), nicotinamide adenine dinucleotide phosphate dehydrogenase, quinone 1 (NQO1) in testis were detected by real-time polymerase chain reaction and Western blot. We found that there was a decrease in sperm count; testis somatic index; the activities of SOD, GSH, total antioxidative capacity ( p < 0.01, respectively) in ATO-treated mice, while there was an increase in the levels of sperm abnormalities, MDA, and 8-OHdG than control ( p < 0.01, respectively). The groups treated with ATO + LU showed recovery of the measured parameters between those of ATO or saline-treated group. The antagonized interaction between ATO and LU was statistically significant ( p < 0.01). Mice treated with ATO + LU also showed greater mRNA expression of Nrf2, HO-1, NQO1, and GST than ATO or saline-treated groups. These findings suggest that LU alleviates reproductive toxicity induced by arsenic in male mice via Nrf2 signaling, which implicates a possible mechanism of LU in preventing the reproductive injury, and elucidates that consuming the rich plant sources of LU will alleviate the reproductive toxicity induced by chemicals.

A High Throughput Screening Assay for Anti-Mycobacterial Small Molecules Based on Adenylate Kinase Release as a Reporter of Cell Lysis

Mycobacterium tuberculosis (Mtb) is well-established to be one of the most important bacterial pathogens for which new antimicrobial therapies are needed. Herein, we describe the development of a high throughput screening assay for the identification of molecules that are bactericidal against Mycobacteria. The assay utilizes the release of the intracellular enzyme adenylate kinase into the culture medium as a reporter of mycobacterial cell death. We demonstrate that the assay is selective for mycobactericidal molecules and detects anti-mycobacterial activity at concentrations below the minimum inhibitory concentration of many molecules. Thus, the AK assay is more sensitive than traditional growth assays. We have validated the AK assay in the HTS setting using the Mtb surrogate organism M. smegmatis and libraries of FDA approved drugs as well as a commercially available Diversity set. The screen of the FDA-approved library demonstrated that the AK assay is able to identify the vast majority of drugs with known mycobactericidal activity. Importantly, our screen of the Diversity set revealed that the increased sensitivity of the AK assay increases the ability of M. smegmatis-based screens to detect molecules with relatively poor activity against M. smegmatis but good to excellent activity against Mtb.

Polymorphisms in the PPARγ gene and their association with metabolic syndrome in Uyghurs and Kazakhs from Xinjiang, China

We investigated the association between polymorphisms rs1801282 and rs3856806 of the PPARγ gene and metabolic syndrome (MS) among Uyghurs and Kazakhs. Mass spectrometry techniques were used to detect the PPARγ genotypes rs1801282 and rs3856806 in 987 subjects, CC genotype and C allele frequencies were 83.6 and 91.7%, respectively, at rs1801282 in Kazakhs, which were higher than those in Uyghurs (72.3 and 85.0%, respectively; P < 0.05). CC genotype and C allele frequencies were 73.6 and 85.3%, respectively, at the rs3856806 loci in Kazakhs, which were higher than those in Uyghurs (60.7 and 77.9%, respectively; P < 0.05). For the rs3856806 polymorphism in Kazakhs, CT/TT genotype and T allele frequencies were 21.2 and 12.4% for MS subjects, which were lower than those for the control group (31.6 and 17.0%, respectively; P < 0.05). Risk analysis of Kazakhs revealed that individuals with the CT and TT genotypes at rs3856806 had an increased risk, 0.524- and 0.770-fold, respectively, of developing MS than those possessing the CC genotype. Individuals with the T allele also had an increase in risk, by 0.699-fold, of developing MS than those with the C allele. For Uyghurs, those with the CC genotype at rs1801282 had higher systolic blood pressure than those with the CG/GG genotype. Among Kazakhs, those with the CC genotype at rs3856806 had higher triglyceride and waist-hip ratio levels but lower high-density lipoprotein cholesterol levels than those with the CT/TT genotype. The rs1801282 and rs3856806 PPARγ polymorphisms differ between Uyghurs and Kazakhs from Xinjiang Province, China.

Evolution of a thienopyrimidine antitubercular relying on medicinal chemistry and metabolomics insights

The metabolic instability of an antitubercular small molecule CD117 was addressed through iterative alteration of a key sulfide substituent and interrogation of the effect on growth inhibition of cultured Mycobacterium tuberculosis. This process was informed by studies of the intramycobacterial metabolism of CD117 and its inactive carboxylic acid derivative. Isoxazole 4e and thiazole 4m demonstrated significant gains in mouse liver microsomal stability with slight losses in whole-cell activity. This work illustrates the challenges of antitubercular hit evolution, requiring a balance of chemical and biological insights.

Hydrogen sulfide in posthemorrhagic shock mesenteric lymph drainage alleviates kidney injury in rats

Posthemorrhagic shock mesenteric lymph (PHSML) is a key factor in multiple organ injury following hemorrhagic shock. We investigated the role of hydrogen sulfide (H₂S) in PHSML drainage in alleviating acute kidney injury (AKI) by administering D,L-propargylglycine (PPG) and sodium hydrosulfide hydrate (NaHS) to 12 specific pathogen-free male Wistar rats with PHSML drainage. A hemorrhagic shock model was established in 4 experimental groups: shock, shock+drainage, shock+drainage+PPG (45 mg/kg, 0.5 h prehemorrhage), and shock+drainage+NaHS (28 µmol/kg, 0.5 h prehemorrhage). Fluid resuscitation was performed after 1 h of hypotension, and PHMSL was drained in the last three groups for 3 h after resuscitation. Renal function and histomorphology were assessed along with levels of H₂S, cystathionine-γ-lyase (CSE), Toll-like receptor 4 (TLR4), interleukin (IL)-10, IL-12, and tumor necrosis factor (TNF)-α in renal tissue. Hemorrhagic shock induced AKI with increased urea and creatinine levels in plasma and higher H₂S, CSE, TLR4, IL-10, IL-12, and TNF-α levels in renal tissue. PHSML drainage significantly reduced urea, creatinine, H₂S, CSE, and TNF-α but not TLR4, IL-10, or IL-12. PPG decreased creatinine, H₂S, IL-10, and TNF-α levels, but this effect was reversed by NaHS administration. In conclusion, PHSML drainage alleviated AKI following hemorrhagic shock by preventing increases in H₂S and H₂S-mediated inflammation.

A virtual screen discovers novel, fragment-sized inhibitors of Mycobacterium tuberculosis InhA

Isoniazid (INH) is usually administered to treat latent Mycobacterium tuberculosis (Mtb) infections and is used in combination therapy to treat active tuberculosis (TB). Unfortunately, resistance to this drug is hampering its clinical effectiveness. INH is a prodrug that must be activated by Mtb catalase-peroxidase (KatG) before it can inhibit InhA (Mtb enoyl-acyl-carrier-protein reductase). Isoniazid-resistant cases of TB found in clinical settings usually involve mutations in or deletion of katG, which abrogate INH activation. Compounds that inhibit InhA without requiring prior activation by KatG would not be affected by this resistance mechanism and hence would display continued potency against these drug-resistant isolates of Mtb. Virtual screening experiments versus InhA in the GO Fight Against Malaria (GO FAM) project were designed to discover new scaffolds that display base-stacking interactions with the NAD cofactor. GO FAM experiments included targets from other pathogens, including Mtb, when they had structural similarity to a malaria target. Eight of the 16 soluble compounds identified by docking against InhA plus visual inspection were modest inhibitors and did not require prior activation by KatG. The best two inhibitors discovered are both fragment-sized compounds and displayed Ki values of 54 and 59 μM, respectively. Importantly, the novel inhibitors discovered have low structural similarity to known InhA inhibitors and thus help expand the number of chemotypes on which future medicinal chemistry efforts can be focused. These new fragment hits could eventually help advance the fight against INH-resistant Mtb strains, which pose a significant global health threat.

Electrodeposition of PbO and its in situ conversion to CH3NH3PbI3 for mesoscopic perovskite solar cells

The perovskite CH₃NH₃PbI₃ is deposited on the mesoscopic TiO₂ film, and used as a light absorber for perovskite solar cells, exhibiting a high PCE of 12.5% under standard AM 1.5 conditions.

Epidemiological analysis of dyslipidemia in adults of three ethnicities in Xinjiang, China

This study investigated the prevalence and distribution of dyslipidemia in adults of Uygur, Kazak, and Han ethnicity in Xinjiang, China. A questionnaire including general data, physical examination (blood pressure, body height, and body weight) and blood lipid [total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C)] was administered to 11,506 adults in Xinjiang, China from 2009 to 2010 using a stratified sampling method. The overall prevalence rates of dyslipidemia in Uygur, Kazak, and Han adults were 42.4, 31.6, and 30.2%, respectively; they were 42.4, 31.8, and 28.2% after age standardization (P < 0.01). After standardization, the overall prevalence rates in Uygur, Kazak, and Han men were 52.6, 35.4, and 33.2%, respectively, which were significantly higher than that in women of the corresponding ethnicities (P < 0.01). In Uygur, Kazak, and Han adults, there were significant differences with respect to the standardized prevalence rates of high TG (9.3, 9.3, and 17.3%), high TC (5.2, 6.9, and 6%), low HDL-C (33.6, 20.8, and 11.1%), and high LDL-C (2.4, 2.9, and 2%) (P < 0.05). The prevalence rates of dyslipidemia in Uygur, Kazak, and Han adults in Xinjiang are higher than the average levels in China, with significant differences in ethnicity, age, and gender. Han adults exhibited the highest prevalence rate of high TG. Meanwhile, Uygur adults had the highest prevalence rate of low HDL-C. Kazak adults had high prevalence rates of high TC, low HDL-C, and high LDL-C.

Engineering diketopyrrolopyrrole sensitizers for highly efficient dye-sensitized solar cells: enhanced light harvesting and intramolecular charge transfer

Two asymmetric DPP dyes with a D–π–A structure are reported, where DPP is used as a bridge to connect the triphenylamine donor and cyanoacetic acid acceptor.

PTEN hypermethylation profiles of Chinese Kazakh patients with esophageal squamous cell carcinoma

Aberrant DNA methylation of promoter region CpG islands may serve as an alternative mechanism to genetic defects in the inactivation of tumor suppressor genes (TSGs) in human malignancies. The aim of this study was to examine the promoter methylation status of the PTEN TSG and its association with esophageal squamous cell carcinoma (ESCC) carcinogenesis in a Chinese Kazakh population, which is known to have a relatively high ESCC incidence and mortality. The methylation status of the PTEN promoter region was determined in patients with ESCC (n = 95) and healthy individuals (n = 65) using highly sensitive Sequenom Epityper assays. The methylation level of the PTEN gene was significantly higher in patients with ESCC than in healthy controls. The median methylation level was 10.0% (interquartile range [IQR]: 7.0-11.0%) in patients with ESCC and 6.0% in controls (IQR: 4.0-9.0%; P = 0.001). PTEN methylation levels were higher in male patients with ESCC than in male controls, whereas a trend toward significance was observed between female patients with ESCC and female controls (P = 0.005 and P = 0.086, respectively). The PTEN methylation level was associated with histopathological grade and lymph node metastasis in patients with ESCC (P = 0.002 and P = 0.009, respectively). To our knowledge, this is the first report to show the presence of PTEN promoter CpG hypermethylation in ESCC and its association with tumor metastasis.

Inhibition of allergic airway inflammation by antisense-induced blockade of STAT6 expression

BACKGROUND

The signal transducer and activator of transcription 6 (STAT6) expression in lung epithelial cells plays a pivotal role in asthma pathogenesis. Activation of STAT6 expression results in T helper cell type 2 (Th2) cell differentiation leading to Th2-mediated IgE production, development of allergic airway inflammation and hyperreactivity. Therefore, antagonizing the expression and/or the function of STAT6 could be used as a mode of therapy for allergic airway inflammation.

METHODS

In this study, we synthesized a 20-mer phosphorothioate antisense oligonucleotide (ASODN) overlapping the translation starting site of STAT6 and constructed STAT6 antisense RNA (pANTI-STAT6), then transfected them into murine spleen lymphocytes and analyzed the effects of antagonizing STAT6 function in vitro and in a murine model of asthma.

RESULTS

In vitro, we showed suppression of STAT6 expression and interleukin (IL)-4 production of lymphocytes by STAT6 ASODN. This effect was more prominent when cells were cultured with pANTI-STAT6. In a murine model of asthma associated with allergic pulmonary inflammation in ovalbumin (OVA)-sensitized mice, local intranasal administration of fluorescein isothiocyanate (FITC)-labeled STAT6 ASODN to DNA uptake in lung cells was accompanied by a reduction of intracellular STAT6 expression. Such intrapulmonary blockade of STAT6 expression abrogated signs of lung inflammation, infiltration of eosinophils and Th2 cytokine production.

CONCLUSION

These data suggest a critical role of STAT6 in the pathogenesis of asthma and the use of local delivery of STAT6 ASODN as a novel approach for the treatment of allergic airway inflammation such as in asthma.

Somatostatin elevates topoisomerase II alpha and enhances the cytotoxic effect of doxorubicin on gallbladder cancer cells

BACKGROUND

Gallbladder cancer is a common and lethal digestive malignancy which is nonsensitive to routine chemotherapy. Doxorubicin (DOX) is one of the major chemotherapeutic drugs for patients with gallbladder cancer. We tried to evaluate if combined use of somatostatin (SST) and DOX could have synergistic effect in the treatment of gallbladder cancer.

METHODS

Cells from the human gallbladder cancer cell line GBC-SD were treated with SST. Cell cycle analysis was determined by flow cytometry. Western blot analysis was performed to determine the protein levels of topoisomerase IIalpha (Topo IIalpha) after SST treatment. RT-PCR was utilized to detect SST receptors in GBC-SD cells. Finally, the chemotherapeutic effect of DOX combined with SST treatment on cellular growth was measured by MTT assay.

RESULTS

SST could induce cell cycle arrest in S phase and upregulate Topo IIalpha expression in GBC-SD cells. GBC-SD cells expressed all 5 subtypes of SST receptors. Finally, combined use of DOX with SST had a synergistic cytotoxic effect on GBC-SD cells.

CONCLUSION

SST, a naturally occurring, nontoxic compound, may represent a novel adjuvant chemotherapeutic agent for patients with gallbladder cancer.

Rapid polymerase chain reaction assay for ipaH and ial genes in feces from shigellosis

AIM: To establish a fast, specific and sensitive diagnostic method for detecting the invasion plasmid antigen H (ipaH) and the invasion-associated locus (ial) DNA sequence of Shigella.

METHODS: Seventy-one stool specimens from patients with acute diarrhea were tested by two methods; a traditional culture method, and a polymerase chain reaction (PCR) and nested-PCR assay. PCR-amplified products were initially evaluated by electrophoresis with 20 g/L agarose gel and visualization by ethidium bromide staining.

RESULTS: Serological assay classified the Shigella isolates as follows: 24 Shigella flexneri, 23 Shigella sonnei and one Shigella dysenteriae. Salmonella was isolated from 23 of the 71 stool specimens by conventional coproculture. PCR assays showed that 46 of the 48 Shigella spp. were positive for the ipaH gene, 34 were positive for the ial gene, and 14 were negative. Nested-PCR assays detected 14 specimens as negative for ial, 12 were positive, and 46 specimens were positive for both the ipaH and ial genes. The ipaH and ial genes were both negative in 23 Salmonella isolates. The kappa test, was used to compare two test results, and the kappa value was 0.937 (P < 0.05).

CONCLUSION: PCR assays detecting the invasion-associated genes of Shigella from feces provided fast, specific and sensitive diagnostic methods.

[An epidemiological survey on paragonimiasis in Jin Miaopu township in Shanxi province]

OBJECTIVE

To investigate the epidemiological factors and tendency of paragonimiasis in Jin Miaopu township in Zezhou county of Shanxi Province, and to understand the current status of public awareness for providing references to paragonimiasis education and prevention.

METHODS

A questionnaire survey was conducted among 2172 villagers probing awareness of paragonimiasis and their experiences of eating crabs; Infection screening and antibody test were also performed by means of ELISA.

RESULTS

The paragonimiasis knowledge coverage rate was zero, and 67.7% (1471/2172) of the respondents claimed their histories of crab eating and 96.7% (29/30) of crabs were infected with metacercaria of paragonimus. Of all the study subjects, 11% (241/2172) of them were infected with the positive rate of 4.1% (89/270).

CONCLUSION

The incidence of paragonimiasis is closely related to dietetic habit in local residents. It is extremely necessary to increase the public awareness of paragonimiasis prevention and control and to improve the living conditions and dietetic habits.

Interference with nuclear factor kappa B and c-Jun NH2-terminal kinase signaling by TRAF6C small interfering RNA inhibits myeloma cell proliferation and enhances apoptosis

The tumor necrosis factor receptor (TNFR)-associated factor (TRAF) family of six adaptor proteins (TRAF1-6) links the TNFR superfamily to the nuclear factor kappa B (NF-kappaB) and activator protein-1 (AP-1) transcriptional activators. Unlike other TRAFs, TRAF6 is also involved in Toll-like/interleukin (IL)-1 receptor (TIR) signal transduction. Thus, inhibition of TRAF6 function could interrupt both CD40 (TNFR family) and IL-1 growth signals, pathways critical to myeloma proliferation. To block TRAF6-mediated IL-1 signaling, we constructed small interfering RNA (siRNA) against TRAF6. We found that siRNA targeting the TRAF6 C-terminal (siTRAF6C) receptor interaction domain specifically reduced only TRAF6 protein expression, without affecting TRAF2 or 5 levels, and substantially interfered with IL-1-induced NF-kappaB and c-Jun/AP-1 activation. Inhibition by siTRAF6C was concentration-dependent. SiTRAF6C also significantly reduced myeloma proliferation and enhanced apoptosis in a similar dose-dependent fashion in vitro. More importantly, marked siTRAF6C growth inhibition was detected in vivo when these cells were implanted into the bone marrow of irradiated normal mice. In contrast, introduction of siRNA derived from the TRAF6 Zn-finger domain or an irrelevant siRNA construct failed to alter cell growth or cell death. These studies suggest that TRAF6 may be a new molecular target to block cell signal transduction important for the survival and proliferation of multiple myeloma cells.

The effects of simulated microgravity on cultured chicken embryonic chondrocytes

Using the cultured chicken embryonic chondrocytes as a model, the effects of simulated microgravity on the microtubular system of the cellular skeleton, extracellular matrix, alkaline phosphatase activity, intracellular free calcium concentration and mitochondrial ATP synthase activity with its oligomycin inhibition rate were studied with a clinostat. The microtubular content was measured by a flow cytometer. The decrease of microtubular content showed the impairment of the cellular skeleton system. Observation on the extracellular matrix by the scanning electron microscopy showed that it decreased significantly after rotating, and the fibers in the extracellular matrix were more tiny and disorderly than that of the control group. It can be concluded that the simulated microgravity can affect the secreting and assembly of the extracellular matrix. In contrast to the control, there was a time course decrease in alkaline phosphatase activity of chondrocytes, a marker of matrix mineralization. Meanwhile a significant drop in the intracellular calcium concentration happened at the beginning of rotation. These results indicate that simulated microgravity can suppress matrix calcification of cultured chondrocytes, and intracellular free calcium may be involved in the regulation of matrix calcification as the second signal transmitter. No significant changes happened in the mitochondrial ATP synthase activity and its oligomycin inhibition rate. Perhaps the energy metabolism wasn't affected by the simulated microgravity. The possible mechanisms about them were discussed.

[Gene analysis of blast resistance in an indica variety Digu]

Digu is one of the important genetic resources in rice breeding for resistance to blast disease in China. In this study, the disease resistance identification in the parental varieties and the population F1, F2 and B1F1 from the crosses involving Digu and four susceptible varieties was carried out by inoculation with two Chinese blast strains, ZB13, and ZB15. The results demonstrated that Digu had one dominant gene Pi-d(t) to ZB13, which had been reported by Li SG. The F2 populations of Digu and other ten different varieties with known resistance genes were inoculated with strains ZB13 and the results further demonstrated that blast resistance of Digu to strain ZB13 was controlled by one dominant resistance gene.

[Molecular tagging of a new recessive gene for late heading in a rice cultivar 8987]

8987 is a late flowering (lf) indica cultivar. In this study, genetic analysis for lf was carried out in the crosses between 8987 and four varieties with different heading time. Inheritance of lf in F1 plants and F2 populations clearly revealed that the lf of 8987 is controlled by one recessive gene. Bulked-segregant method and cosegregation analysis in F2 population were used to screen molecular markers, which were linked with lf gene. The results showed that the lf gene was mapped between the two RFLP marker C213 and RG404 on chromosome 7. The tagged gene will be utilized in molecular marker assisted selection in the future rice breeding program for new varieties.

[Utilization of a microsatellite marker to identify rice blast resistance gene in two segregating populations]

The microsatellite (SSLP) marker RM262, which is tightly linked to the blast resistance gene Pi-d(t) in rice, provides means to conduct marker-aided selection in a rice breeding program. The objective of this study was to investigate the ability of this marker to select the blast resistance gene, Pi-d(t), in two crosses for rice blast resistance breeding. The products with amplified the microsatellite primers were polymorphic between the three varieties examined. To examine the power of the identified microsatellite marker in predicting the Pi-d(t) locus, we determined the genotypes of the two F2 populations at the Pi-d(t) locus by performing progeny testing for the disease respones. The results indicated an accuracy of more than 98% in identifying the resistant plants in both populations. Therefore the microsatellite marker can be utilized in marker-assisted selection and breeding for new varieties with blast resistance.

[Application of microsatellite markers for the seed purity examination of a hybrid rice, Gangyou-22]

For seed commercialization of hybrid rice it is necessary to examine the purity of its seeds before field-production, because the seed purity is closely related to their heterosis performance and yield increase. In this research, 160 microsatellite markers were used for PCR amplification of rice seedling DNAs of Gangyou-22, which is a major hybrid rice in China, and its parents, Gang46A(CMS line) and CDR22(restorer line). A microsatellite marker, RM168, was screened out for its ability to produce polymorphic bands specific to each of the two parents but different from other 22 restorer lines and 9 cultivars. This provides an accurate and efficient method to examine the purity of a hybrid rice at an earlier time. Amplification of DNAs extracted from seeds and application of two microsatellite markers in one PCR system can further simplify the procedure and improve the accuracy of the seed purity examination.

Sympathetic control of BP and BP variability in borderline hypertensive rats on high- vs. low-salt diet

This experiment tested the effect of a high-salt diet on the interaction between arterial blood pressure (BP) and sympathetic nerve activity (SNA) at rest and during a controlled behavioral stress at an early stage in the development of hypertension in borderline hypertensive rats (BHR). Ten rats were maintained on a high-salt diet (8% NaCl) while 14 were fed a low-salt diet (0.8% NaCl) for 8 wk. They were trained in a Pavlovian paradigm by following a conditional stimulus tone (CS+) with a 0.5-s shock. SNA and BP were measured by implanted electrodes around the left renal nerve and a catheter in the femoral artery, respectively. There were no detectable between-group differences in BP or in BP variability in the resting animal at the end of the 8-wk dietary treatment. Moreover, there were no significant between-group differences in the changes in SNA evoked by the CS+ tone. Conversely, the amplitude of the initial conditional increase in BP was significantly (P < 0.05) larger in the high-salt (6 +/- 0.6 mmHg; mean +/- SEM) compared with the low-salt (4 +/- 0.4 mmHg) group. In addition, the BP excursion (peak/trough) during CS+ was larger in the high (18.2 +/- 6.1 mmHg)- vs. low-salt (5.8 +/- 0.4 mmHg) diet-fed subjects. The ratio of the average percent change in mean BP to the average percent change in SNA at the beginning of CS+ was 0.029 +/- 0.004 for the low-salt group and 0.041 +/- 0.006 for the high-salt group. We find that, before the development of overt hypertension, the enhanced conditional BP response in the high-salt BHR appears to reside at the interface between changes in SNA and the effector response and not within the central nervous system. These observations help explain the increasing BP variability typically observed with the development of hypertension in humans.

Low-frequency renal sympathetic nerve activity, arterial BP, stationary "1/f noise," and the baroreflex

The object of this study is to quantify the very low frequency (i.e., <0.1 Hz) interactions between renal sympathetic nerve activity (SNA) and arterial blood pressure (ABP). Six rats were instrumented for chronic recordings of SNA and ABP. Data were collected 24 h after surgery at 10 kHz for 2-5 h and subsequently compressed to a 1-kHz signal. The power spectra and ordinary coherence were calculated from data epochs up to 1 h in length. The very low frequency spectra for both variables were fitted to a constant times f (-beta). The peak magnitude squared of the coherence near 0.4 Hz was 0.82 +/- 0.08, but the apparent linear coherence fell off quickly at lower frequencies so that it was close to zero for frequencies <0.1 Hz. Moreover, at these low frequencies beta, as computed by a coarse grain spectral analysis, was significantly (P < 0.01) different for SNA (0.66 +/- 0.12) and ABP (1.12 +/- 0.14). Assuming that SNA and ABP are stationary time series, the results of our classical spectral analysis would indicate that SNA and ABP are not linearly correlated at frequencies with a period more than approximately 10 s. Accordingly, we tested for stationarity by computing the spectral coherence and found that SNA and ABP are not stationary "1/f noise" within the frequency range from 0.02 to 2.0 Hz. Rather the SNA exerts control over the cardiovascular system through intermittent bursts of activity. Such intermittent behavior can be modeled by nonlinear dynamics.