Extraction of heterocyclic amines and polycyclic aromatic hydrocarbons from pork jerky and the effect of flavoring on formation and inhibition.

Heterocyclic amines (HAs) and polycyclic aromatic hydrocarbons (PAHs)are widely distributed in foods.This study aims to extract PAHs and HAs from pork jerky simultaneously by QuEChERS for analysis by GC-MS/MS and UPLC-MS/MS, respectively. Also,the effects of flavoring materials and processing temperature on the formation of PAHs and HAswere studied. Acetonitrile containing 1% acetic acid possessed the highest extraction efficiency, with high accuracy and precision being attained forHAs and PAHs. Pork jerky roasted at 220℃ generated a higherPAHs content than180℃, but unaffected the HAs formation.Addition of sugarreduced formation ofboth HAs and PAHs during roasting, while soy sauce reduced somePAHs and promotedHAs formation. Incorporation of 0.5% curcumaorcinnamon powderinhibited HA formation with amore pronounced effect being shown by the latter,but neither inhibitedPAH formation. The correlation between HA and PAH formation was assessed by principle component analysis.

[A comparison of CAS risk model and CHA2DS2-VASc risk model in guiding anticoagulation treatment in Chinese patients with non-valvular atrial fibrillation].

Objective: To compare the differences between CAS risk model and CHA2DS2-VASc risk score in predicting all cause death, thromboembolic events, major bleeding events and composite endpoint in patients with nonvalvular atrial fibrillation. Methods: This is a retrospective cohort study. From the China Atrial Fibrillation Registry cohort study, the patients with atrial fibrillation who were>18 years old were randomly divided into CAS risk score group and CHA2DS2-VASc risk score group respectively. According to the anticoagulant status at baseline and follow-up, patients in the 2 groups who complied with the scoring specifications for anticoagulation were selected for inclusion in this study. Baseline information such as age and gender in the two groups were collected and compared. Follow-up was performed periodically to collect information on anticoagulant therapy and endpoints. The endpoints were all-cause death, thromboembolism events and major bleeding, the composite endpoint events were all-cause death and thromboembolism events. The incidence of endpoints in CAS group and CHA2DS2-VASc group was analyzed, and multivariate Cox proportional risk model was used to analyze whether the incidence of the endpoints was statistically different between the two groups. Results: A total of 5 206 patients with AF were enrolled, average aged (63.6±12.2) years, and 2092 (40.2%) women. There were 2 447 cases (47.0%) in CAS risk score group and 2 759 cases (53.0%) in CHA2DS2-VASc risk score group. In the clinical baseline data of the two groups, the proportion of left ventricular ejection fraction<55%, non-paroxysmal atrial fibrillation, oral warfarin and HAS BLED score in the CAS group were lower than those in the CHA2DS2-VASc group, while the proportion of previous diabetes history and history of antiplatelet drugs in the CAS group was higher than that in the CHA2DS2-VASc group, and there was no statistical difference in other baseline data. Patients were followed up for (82.8±40.8) months. In CAS risk score group, 225(9.2%) had all-cause death, 186 (7.6%) had thromboembolic events, 81(3.3%) had major bleeding, and 368 (15.0%) had composite endpoint. In CHA2DS2-VASc risk score group, 261(9.5%) had all-cause death 209(7.6%) had thromboembolic events, 112(4.1%) had major bleeding, and 424 (15.4%) had composite endpoint. There were no significant differences in the occurrence of all-cause death, thromboembolic events, major bleeding and composite endpoint between anticoagulation in CAS risk score group and anticoagulation in CHA2DS2-VASc risk score group (log-rank P =0.643, 0.904, 0.126, 0.599, respectively). Compared with CAS risk score, multivariable Cox proportional hazards regression models showed no significant differences for all-cause death, thromboembolic events, major bleeding and composite endpoint between the two groups with HR(95%CI) 0.95(0.80-1.14), 1.00(0.82-1.22), 0.83(0.62-1.10), 0.96(0.84-1.11), respectively. All P>0.05. Conclusions: There were no significant differences between CAS risk model and CHA2DS2-VASc risk score in predicting all-cause death, thromboembolic events, and major bleeding events in Chinese patients with non-valvular atrial fibrillation.

[Clinical analysis of left atrial appendage occlusion for stroke prevention in elderly patients with atrial fibrillation].

To evaluate the efficacy and safety of left atrial appendage occlusion (LAAO) in patients with atrial fibrillation (AF) over 75 years. A total of 82 patients with AF who underwent LAAO successfully in Beijing Anzhen Hospital from March 2014 to March 2019 were divided into two groups according to age: the elderly group (aged>75 years) and the young group (aged ≤75 years). Risk of perioperative complications and incidence of ischemic stroke and major bleeding during follow-up were retrospectively analyzed. The results showed that there were no significant differences in procedure-related ischemic stroke(0 vs.1.6%,P=0.768) and major bleeding (0 vs.1.6%,P=0.768) during perioperative period between the two groups. No complications as death or pericardial tamponade occurred in the two group. During a (25.9±15.9) months period of followed up, ischemic stroke event rate was 3.6/100 person-years in the elderly group and 4.9/100 person-years in the young group, respectively. Major bleeding event rate was 2.5/100 person-years in the elderly group and 0/100 person-years in the young group, respectively. Compared with the expected ones, the relative risk reduction (RRR) of stroke in the elderly group was more profound than that in the young group (32.0% vs. 25.0%), while the risk of major bleeding in the young group was significantly lower than that in the elderly group (RRR 100% vs. 56.9%). Therefore, LAAO might be suitable for stroke prevention in the elderly AF patients.

[Feasibility and safety of intracardiac ultrasound-assisted atrial septal puncture during radiofrequency ablation for atrial fibrillation].

Objective: To explore the feasibility and safety of intracardiac ultrasound-assisted atrial septal puncture (ASP) during radiofrequency ablation for atrial fibrillation. Methods: We enrolled 241 consecutive patients scheduled to radiofrequency ablation for atrial fibrillation in Beijing Anzhen Hospital from July to September 2020. Inclusion criteria: patients aged over 18 years with a clear electrocardiogram record of atrial fibrillation. Patients were divided into 2 groups: ASP with ultrasound-assisted X-ray (ultrasound group, n=123), ASP under X-ray alone (X-ray group, n=118). Clinical features of patients including age, sex, percent of paroxysmal atrial fibrillation, and repeat ablation, CHA2DS2-VASc score and past history (hypertension, diabetes mellitus, coronary artery disease, stroke/transient ischemic attack (TIA), valve diseases) and echocardiographic parameters (left atrial dimension, left ventricular ejection fraction, left ventricular end-diastolic dimension) were obtained and compared. The first-pass rate, radiation exposure time, duration of ASP, and complications of ASP were also compared between the two groups. Results: The age of patients in this cohort was (62.5±8.0) years, and the proportion of males was 57.0% (n=138). Among them, the proportion of paroxysmal atrial fibrillation was 56.0% (n=135), and the ratio of repeat ablation was 17.8% (n=43). Age, sex, percent of paroxysmal atrial fibrillation, history of hypertension, diabetes mellitus were similar between the two groups. The first-pass rate was significantly higher in the ultrasound group than in the X-ray group (94.3% (116/123) vs. 79.7% (94/118), P=0.001); the exposure time of X-ray was significantly shorter in the ultrasound group than in the X-ray group ((31.3±7.9) s vs. (124.8±35.7) s, P<0.001), while the duration of ASP was longer in the ultrasound group ((10.1±1.8) minutes vs. (8.2±1.3) minutes, P<0.001). In terms of complications, the incidence of puncture into the pericardium was lower in the ultrasound group (0 vs.3.4% (4/118), P=0.039); the rate of transient ST-segment elevation post ASP was similar between the ultrasound group and X-ray group (2.4% (3/123) vs. 1.7% (2/118), P=0.999). Conclusion: Intracardiac ultrasound-assisted atrial septal puncture can effectively improve the accuracy of atrial septal puncture, shorten the radiation exposure time, and reduce the complications related to atrial septal puncture.

[Research progress of relationship between vitamin K and type 2 diabetes].

Objective: To systematically review research on the association between vitamin K and type 2 diabetes and diabetes-related biomarkers in humans, and evaluate the role of vitamin K in the prevention of type 2 diabetes. Methods: "Vitamin K", "type 2 diabetes" and related terms were searched in PubMed, EMBASE, China National Knowledge Infrastructure (CNKI) and Wanfang Med Online up to November 2018. Results: A total of 1 Chinese and 12 English articles were included. Among 6 observational studies, 5 of them showed that higher dietary vitamin K intake and plasma vitamin K level were associated with the decrease of the risk of type 2 diabetes. Among 6 clinical intervention studies, 5 of them indicated that the supplementation of vitamin K(1) or K2 could have positive influence on insulin metabolism. One Mendelian randomization study showed higher circulation vitamin K level might reduce the risk of type 2 diabetes. Conclusion: Vitamin K plays an important role in the prevention and control of type 2 diabetes, which may be related to the improvement of insulin metabolism and blood glucose level.

Molecular screening of multidrug-resistance tuberculosis by a designated public health laboratory in Taiwan.

This manuscript describes our experience in early identifying MDR-TB cases in high-risk populations by setting up a single-referral molecular diagnosis laboratory in Taiwan. Taiwan Centers for Disease Control designated a single-referral laboratory to provide the GenoType MTBDRplus test for screening high-risk MDR-TB populations nationwide in 2012-2015. A total of 5,838 sputum specimens from 3,308 patients were tested within 3 days turnaround time. Compared with the conventional culture and drug susceptibility testing, the overall performance of the GenoType MTBDRplus test for detecting TB infection showed accuracy of 70.7%, sensitivity of 85.9%, specificity of 65.7%, positive predictive value of 45.5%, and negative predictive value of 93.3%. And the accuracy of detecting rifampin (RIF) resistance, isoniazid (INH) resistance, and MDR-TB (resistant to at least RIF and INH) were 96.5%, 95.2%, and 97.7%, respectively. MDR-TB contacts presented a higher rate of mutated codons 513-519, GenoType MTBDRplus banding pattern: rpoB WT3(-), and rpoB WT4(-) than the treatment failure group. The MDR-TB contact group also had a higher rate of inhA C15T mutation, banding pattern: inhA WT1(-), and inhA MUT1(+) than the recurrent group. Resistance profiles of MDR-TB isolates also varied geographically. The referral molecular diagnosis system contributed to rapid detection and initiation of appropriate therapy.

A pilot external quality assurance programme for line-probe assay detection of anti-tuberculosis drug resistance.

BACKGROUND: Multidrug-resistant tuberculosis (MDR-TB; resistance to isoniazid and rifampicin) is difficult to detect and control. Line-probe assays (LiPA) are widely used for the rapid detection of MDR-TB. OBJECTIVE: To ensure the quality of the test, a pilot external quality assurance (EQA) programme was initiated to assess the feasibility of running such a programme and the possibility of improving the proficiency of TB laboratories in performing the test. DESIGN: Prepared filter-paper-based Mycobacterium tuberculosis DNA samples were shipped to participant laboratories for LiPA EQA. The tests were performed blind, and the results were returned to the organising laboratory for comparison and analysis. RESULTS: A total of four rounds of EQA samples were dispatched to five laboratories in four countries. Overall inter- and intra-laboratory reproducibility was respectively 97% and 96%. The strengths and weaknesses of the participant laboratories in performing the test were discussed. CONCLUSION: A LiPA EQA programme can ensure quality and improve the performance of TB laboratories. This is a critical step during the initial stages at the time of setting up this method of testing.

High-throughput characterization of stresses in thin film materials libraries using Si cantilever array wafers and digital holographic microscopy.

We report the development of an advanced high-throughput stress characterization method for thin film materials libraries sputter-deposited on micro-machined cantilever arrays consisting of around 1500 cantilevers on 4-inch silicon-on-insulator wafers. A low-cost custom-designed digital holographic microscope (DHM) is employed to simultaneously monitor the thin film thickness, the surface topography and the curvature of each of the cantilevers before and after deposition. The variation in stress state across the thin film materials library is then calculated by Stoney's equation based on the obtained radii of curvature of the cantilevers and film thicknesses. DHM with nanometer-scale out-of-plane resolution allows stress measurements in a wide range, at least from several MPa to several GPa. By using an automatic x-y translation stage, the local stresses within a 4-inch materials library are mapped with high accuracy within 10 min. The speed of measurement is greatly improved compared with the prior laser scanning approach that needs more than an hour of measuring time. A high-throughput stress measurement of an as-deposited Fe-Pd-W materials library was evaluated for demonstration. The fast characterization method is expected to accelerate the development of (functional) thin films, e.g., (magnetic) shape memory materials, whose functionality is greatly stress dependent.

Syntheses of chromium pentacarbonyl derivatives of arsenic(V) and antimony(V). contrasting chemical reactivity with organic halogen derivatives.

We have synthesized a new series of chromium-group 15 dihydride and hydride complexes [H(2)As(Cr(CO)(5))(2)](-) (1) and [HE(Cr(CO)(5))(3)](2)(-) (E = As, 2a; E = Sb, 2b), which represent the first examples of group 6 complexes containing E-H fragments. The contrasting chemical reactivity of 2a and 2b with organic halogen derivatives is demonstrated. The reaction of 2a with RBr (R = PhCH(2), HC triple bond CCH(2)) produces the RX addition products [(R)(Br)As(Cr(CO)(5))(2)](-) (R = PhCH(2), 3; R = C(3)H(3), 4), while the treatment of 2b with RX (RX = PhCH(2)Br or HC triple bond CCH(2)Br, CH(3)(CH(2))(5)C(O)Cl) forms the halo-substituted complexes [XSb(Cr(CO)(5))(3)](2-) (X = Br, 5; X = Cl, 6). Moreover, the dihaloantimony complexes [XX'Sb(Cr(CO)(5))(2)](-) can be obtained from the reaction of 2b with the appropriate organic halides. In this study, a series of organoarsenic and antimony chromium carbonyl complexes have been synthesized and structurally characterized and the role of the main group on the formation of the resultant complexes is also discussed.

Management of ureteropelvic obstruction in the first year of life.

From July 1971 until December 1978 we treated 19 male and 5 female children less than 1 year old for ureteropelvic junction obstruction. Diagnosis was based on high dose excretory urography with delayed films. Ultrasound was performed in some cases to confirm hydronephrosis. Cystoscopy and retrograde pyelography were not required. Of 32 obstructed kidneys 27 were repaired by dismembered reduction pyeloureteroplasty. Of 8 patients with bilateral involvement 3 underwent unilateral repair only because of lesser contralateral obstruction and 1 underwent unilateral nephrectomy. Of the 27 repairs 20 were protected by nephrostomy or pyelostomy drainage plus a small caliber silicone rubber or polyvinyl stent. Of the 6 non-stented repairs 2 had delayed opening of the repair. A frozen section renal biopsy aided in a decision to repair the kidney in 4 of 6 instances and in 10 other instances a renal biopsy was obtained for prognostic purposes. There were no secondary nephrectomies, although 2 boys required reoperations for a successful result. Instillation pyelography with fluoroscopic monitoring was used to determine when the tubes could be removed. Generally, we removed the stent 4 or 5 days postoperatively and the nephrostomy at a variable time after demonstration of patency of repair. In this group of small children pyelostomy or nephrostomy and intubation of the repair are useful additions to the surgical technique to prevent obstruction of the tiny and delicate infant ureter by anastomotic edema or kinking of the repair.