P4528Feasibility and safety of left bundle branch area pacing by transvenous approach through the interventricular septum in patients with left bundle branch block

Background

His bundle pacing (HBP) has been shown to correct left bundle branch block (LBBB), however it often requires high pacing output and the success rate is variable.

Objective

To assess the feasibility and safety of left bundle branch area pacing (LBBAP) in patients with LBBB.

Methods

From Apr 2014 to Aug 2018, patients with LBBB from multicenters indicated for CRT or pacing therapy were included. LBBAP was performed by advancing the MDT 3830 lead deep into the septum about 1 cm distal to the His bundle region (Figure 1F). Pacing characteristics, success rate, threshold and R-wave amplitude were assessed.

Results

A total of 94 patients aged 68.3±10.7 y with the native QRS duration of 167.2±17.2 ms were included. In 92 patients, LBBAP was successfully achieved and demonstrated RBBB pattern during unipolar tip pacing (UTP), with the paced QRS duration of 116.4±12.6ms (Figure 1C). Fusion of LBBAP and native conduction via the RBB eliminated RBBB and resulted in an average QRS duration of 103.2±10.1 ms (Figure 1D). LBB potential could be recorded from the LBB lead during correction of LBBB by HBP in 21 patients who used two leads method (His lead and LBB lead, Figure 1B). Output dependent selective and non-selective LBBAP were demonstrated in 48 patients (Figure 1C, D). The LBB capture threshold by UTP was 0.53±0.18V/0.5ms at acute and 0.62±0.17V/0.5ms at 6 months and 0.65±0.2V/0.5ms at 1 year. The R-wave amplitude were 11.4±5.2mV, 12.4±5.8mV and 12.0±5.8mV at acute, 6 month and 1 year. During follow-up, only one patient had an increase in LBB capture threshold to 2.5V/0.5ms at 3 months and there were no other complications such as dislodgment, infections, embolism or stroke associated with the implantation.

Conclusion

Permanent LBBAP is feasible and safe in patients with LBBB.

[Study on correlation between alcohol consumption and obesity in adults in China]

Objective: To evaluate the correlation between alcohol consumption and obesity in adults in China. Methods: The information about alcohol consumption were collected at the baseline survey of the China Kadoorie Biobank. The general obesity and central obesity were defined by BMI and waist circumference (WC) respectively. Logistic regression model was employed to examine the relationship of drinking behavior with general obesity and central obesity. Results: A total of 249 873 adults were included. A J-shaped relationship was observed between alcohol consumption and obesity measurement index (BMI and WC) in men. Compared with non-drinkers, the proportion of general obesity and central obesity were lower in light drinkers (men: OR=0.65, 95%CI: 0.59-0.71 and OR=0.93, 95%CI: 0.88-0.98; women: OR=0.77, 95%CI: 0.65-0.91 and OR=0.89, 95%CI: 0.80-0.99). In men, the proportion of general obesity and central obesity was highest in heavy drinkers (OR=1.21, 95%CI: 1.12-1.32; OR=1.33, 95%CI: 1.27-1.40). BMI and WC were higher in those with a drinking frequency of 3-5 d/week, with largest of proportion of central obesity (men: OR=1.23, 95%CI: 1.16-1.31; women: OR=1.13, 95%CI: 0.99-1.28). The risk for central obesity in men who began drinking every week before 20 years old was 1.24 times higher than non-drinkers (95%CI: 1.16-1.33). Those who drank beer had lower proportion of general obesity (men: OR=0.74, 95%CI: 0.67-0.82; women: OR=0.54, 95%CI: 0.43-0.68). Conclusion: The proportion of obesity was lower in light drinkers but higher in heavy drinkers; and the earlier drinking started, the higher the risk for obesity was.

[Cross-sectional survey of life quality of patients with deep partial-thickness and above burns on head and face at discharge and analysis of its influencing factors]

Objective: To study the quality of life and its influencing factors of patients with deep partial-thickness and above burns on head and face at discharge, and to guide clinical nurses to provide targeted nursing for patients. Methods: A cross-sectional survey was conducted on 42 patients with deep partial-thickness and above burns on head and face who met the inclusion criteria. The patients were hospitalized from January 2014 to November 2017 in the Department of Burns and Plastic Surgery of our hospital and were selected by adopting the convenient sampling method. On the day before discharge, the Chinese version of the Abbreviated Burn Specific Health Scale was used to assess the scores in various fields of patients' quality of life and total scores. The self-designed general situation questionnaire was used to investigate the gender, age, education level, occupation, marital status, cause of injury, and source of expenses of patients, and the scores in various fields of quality of life of patients in various general conditions and total scores were recorded. Data were processed with t test or one-way analysis of variance. The indicators with statistically significance in the total score difference in the above analysis were chosen, and multivariate linear regression analysis was performed to screen the factors influencing the quality of life of patients. Results: Totally 42 groups of questionnaires were sent out and 42 groups of valid questionnaires were retrieved. The effective recovery rate was 100%. The total score of quality of life of patients at discharge was (49±10) points. The scores of general health status (57±23) points, social relations (56±18) points, physical function (49±17) points, and mental health (41±20) points were ranked from high to low. There were statistically significant differences in the scores of physical function, mental health, and general health status among patients of different age groups (F=8.115, 14.182, 19.285, P<0.01). There were statistically significant differences in the scores of mental health, social relations, and general health status among patients with different educational levels (F=3.312, 51.176, 21.852, P<0.05 or P<0.01). There were statistically significant differences in the scores of mental health and general health status among patients with different occupations (F=3.667, 2.947, P<0.05). The scores of mental health and social relations of married patients were significantly higher than those of unmarried patients (t=27.096, 4.885, P<0.05 or P<0.01). There were statistically significant differences in the scores of physical function, mental health, social relations, general health status of patients with different causes of injury (F=3.000, 5.438, 4.005, 9.125, P<0.05 or P<0.01). There were statistically significant differences in the scores of mental health and general health status of patients with different sources of expenses (F=10.456, 3.368, P<0.05 or P<0.01). The total scores of quality of life of patients with different gender and causes of injury were similar (t=0.407, F=1.145, P>0.05); there were statistically significant differences in the total scores of quality of life of patients of different age groups, with different education levels, occupations, sources of expenses, and marital status (F=2.947, 17.064, 9.324, 4.101, t=7.225, P<0.05 or P<0.01). Multivariate linear regression analysis showed that age, education level, occupation, marital status, and source of expenses were the factors influencing the quality of life of patients at discharge (t=-2.437, 8.037, -2.994, 5.016, 3.519, P<0.05 or P<0.01). Conclusions: The quality of life of patients with deep partial-thickness and above burns on head and face is at a low level at discharge. The influencing factors include age, education level, occupation, marital status, and source of expenses. Nurses should screen the relevant items when the patient is hospitalized. Emphasis should be laid on young, with undergraduate and above education, unmarried, self-funded patients, and those engaged in occupations with high facial requirements, to minimize the negative mood of patients, encourage them to face life, choose the right career, and improve their quality of life.

[Diagnostic value of two immunoassays for detecting heparin/PF4 complex antibodies in heparin-induced thrombocytopenia]

Objectives: To assess the diagnostic values of latex immunoturbidimetric assay (LIA) and particle immunofiltration assay (PIFA) for heparin-induced thrombocytopenia (HIT) . Methods: Samples from 94 patients with suspected HIT from May 2016 to July 2018 in our hospital were prospectively analyzed by the two immunoassays. Their medical records and further follow-up data were also collected and analyzed by our hematologists to make the 4Ts scores and confirm the diagnosis of HIT, respectively. Performance characteristics of the two immunoassays were assessed, including sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) . Their post-test probabilities (PTP) were also calculated based on the 4Ts score. Results: Among 94 cases, 15 (16.0%) had a positive HIT, including 6 of 37 (16.2%) with an intermediate, and 9 of 15 (60.0%) with a high 4Ts score. PIFA operating characteristics were: sensitivity 100.0% (15/15) , specificity 51.9% (41/80) , PPV 28.3% (15/53) , NPV 100.0% (41/41) . The positive PTP in intermediate and high 4Ts score group were 28.7% and 75.7%, respectively, while negative PTP were all 0. At manufacturers' cutoffs, LIA operating characteristics were: sensitivity 66.7% (10/15) , specificity 94.9% (75/79) , PPV 71.4% (10/14) and NPV 93.8% (75/80) . The positive and negative PTP in intermediate 4Ts score group were 71.8% and 6.3%, while 95.2% and 34.4% in high 4Ts score group, respectively. Receiver operating characteristic (ROC) analysis manifested that LIA was preferable than PIFA, and combining the 2 assays together was significantly better than single test. Conclusions: 4Ts score is still an important tool for the diagnosis of HIT. Combining clinical score with heparin/PF4 antibody assay can increase the accuracy of confirming or excluding HIT. Although PIFA is inferior to LIA in the diagnostic value, its user friendliness and 100% NPV have major advantages. Combining the 2 assays together can achieve a higher diagnostic value.

[Association between fruit consumption and stroke in adults in Qingdao: a prospective study]

Objective: To understand the fruit consumption of adults of Qingdao and examine the association between fruit consumption and stroke. Methods: We analyzed baseline data and stroke incidence of the participants who were aged 30-79 years and had been enrolled into the China Kadoorie Biobank (CKB) study from Qingdao city. Cox proportional hazards regression model was conducted to estimate the association of fruit consumption with risk of stroke. Results: A total of 35 509 participants were investgated in the baseline survey. Ratio of male to female was 1∶1.27, and the average age was (50.3±10.2) years. Respondents with higher frequency of fruit consumption were younger, more women, with higher education level and higher income (P<0.05). A total of 1 011 new cases of stroke were observed, with a stroke incidence of 387.63/100 000 person-years. Multivariate Cox regression analysis showed that fruit consumption had a protective effect on stroke incidence. Compared to the respondents who never consumed fruit, respondents who consumed fruit more than 4 days per week had a 44% lower risk of stroke incidence (HR=0.56, 95%CI: 0.50-0.62, P<0.05), and the risk reduced by 46% (HR=0.54, 95%CI: 0.46-0.64, P<0.05) and 42% (HR=0.58, 95%CI: 0.52-0.69, P<0.05) in male and female, respectively. Further adjustment for WC, BMI, SBP and random blood glucose did not change the association. Conclusion: Increasing fruit consumption can effectively decrease the risk of stroke. People should increase fruit consumption advisably to set up reasonable and healthy dietary habits.

[Study of genetic etiology in fetuses with severely short limbs in the first and second trimester using whole exome sequencing]

Objective: To investigate pathogenic genes related to the phenotype of fetus with severely short limbs in the first and second trimester by whole exome sequencing (WES). Methods: Thirteen fetuses with severely short limbs detected by ultrasonography in the first and second trimester admitted in Chinese PLA General Hospital from September 2016 to June 2018 were collected. All cases were performed induced abortion, 6 of which were carried out karyotype analysis of amniotic fluid at the same time. WES and copy number variations (CNV) were performed on specimens from fetal tissues after labor induction. The suspected pathogenic mutations were validated by Sanger sequencing reactions. Results: No abnormal karyotypes or pathological CNV were found. In 10 fetuses, pathogenic or possibly pathogenic mutations were detected in the following genes: COL2A1, FGFR3, COL1A1, COL1A2, DYNC2LI1 and TRIP11, all of which were essential to skeletal development. The diagnostic yield of WES in the fetuses with severe short limbs was 10/13. Conclusions: In the first and second trimester, most of the fetuses with extremely short limbs suffer from monogenic diseases. WES is likely to be a valuable diagnostic testing option for the fetuses with severe short limbs.

The earliest human occupation of the high-altitude Tibetan Plateau 40 thousand to 30 thousand years ago

The Tibetan Plateau is the highest and one of the most demanding environments ever inhabited by humans. We investigated the timing and mechanisms of its initial colonization at the Nwya Devu site, located nearly 4600 meters above sea level. This site, dating from 40,000 to 30,000 years ago, is the highest Paleolithic archaeological site yet identified globally. Nwya Devu has yielded an abundant blade tool assemblage, indicating hitherto-unknown capacities for the survival of modern humans who camped in this environment. This site deepens the history of the peopling of the "roof of the world" and the antiquity of human high-altitude occupations more generally.

[Brain alteration in neonates with congenital heart disease using apparent diffusion coefficient histograms]

Objective: To evaluate the value of apparent diffusion coefficient (ADC) histogram in neonatal brain alteration with congenital heart disease (CHD). Methods: MRIs of 60 neonates with CHD confirmed by echocardiography were retrospectively analyzed in Children's Hospital of Nanjing Medical University from January 2012 to December 2016.Twenty-two MRIs of neonates with mild pneumonia or scalp hematoma who were suspicious of brain disease but normal MRI findings were enrolled as normal control.MRIcron and ImgJ softwares were used to acquire ADC histogram.The correlation between the gestational age and ADC histogram values were calculated respectively.Then t-test was used to analyze the differences of the histogram values and the diagnostic efficacy of different parameters was analyzed using the receiver operating characteristic curve. Results: The ADC values were significantly correlated with the gestational age (P<0.05). The 70th-90th ADC, skewness, kurtosis and variance were statistically significant (P<0.05). The area under the curve of the 90th ADC value was the largest at 0.698. Conclusions: The ADC histogram can quantify and objectively provide more diffusion information of brain tissue. It is a rapid and feasible quantitative method to identify brain changes in neonates with CHD.

Influence of tool edge waviness on the diffraction effect of diamond-turned optics: theoretical simulation and experimental validation

In this work, the influence of tool edge waviness on the diffraction effect of diamond-turned optics is simulated theoretically and further validated experimentally. In simulation, a 3D surface topography model with consideration of the influence of tool edge waviness is established, in which the variation of tool edge profile is estimated by a linear model in relation to the cutting distance. The results show that the diffraction effect represented in simulation is consistent with the experimental observation. With the deterioration of tool edge waviness, the diffraction efficiency of the specular light decreases, but the high-order diffracted light intensively distributes in the horizontal direction on the receiving screen. Such observation can be attributed to the subgrating effect induced by the periodic duplication of the tool edge profile on the machined surface, which heavily depends on the deterioration of tool edge waviness. Finally, a waviness-controlled diamond tool is recommended to finish a diffraction-free optics by the diamond turning process. Moreover, the diffraction effect can also be employed to monitor the dynamic wear of the cutting tool in diamond turning.

[Evaluating auditory pathway by promontory stimulation test and postoperative hearing rehabilitation(28 cases)]

Objective:Objective:〖WT〗To evaluate auditory pathway in patients by promontory stimulation test(PST) before artificial cochlear implantation(CI), and to analyze the relationship between postoperative hearing rehabilitation and PST. Method:Selecting 28 cases of adult subjects without residual hearing who accepted promontory stimulation test, different etiology led to bilateral severe sensor neural deafness. PST was examined by measuring the electric auditory threshold(T value) and maximum comfort threshold(M value) of 50, 100 and 200 Hz pulse square waves, and by measuring frequency discrimination. Cochlear implantation was performed in 22 patients detected electrical hearing. NRT and speech perception of disyllabic words were tested 12 months later. The data was analyzed by statistically. Result:Twenty-two patients could be detected, the average T value of PST of 100 and 200 Hz:(14.21±12.86) μA, (20.37±19.19) μA, M value: (33.88 ±21.79) μA, (47.92±28.93) μA, the dynamic range: (21.18±14.15) μA, (27.55±20.40) μA. 14 patients can distinguish the frequency difference. 22 patients accepted hearing 1 month after surgery. The average hearing threshold at 12 months is(25.87±2.35) dB to(41.27±4.55) dB. The average speech perception rate at 12 months is(74.37±15.19)% in quiet environment, and it was significantly difference(P<0.05) between two groups in frequency discrimination ability. Postoperative speech perception outcome correlated with the dynamic range of the PST at 100 and 200 Hz, and the T value of 100 Hz and the T and M values of 200 Hz, there were statistically significant difference(P<0.05). Conclusion:PST can be used to evaluate the auditory pathway in difficult cases before cochlear implantation, and to predict functional outcome after cochlear implant surgery.

[Analysis on treatment of eight extremely severe burn patients in August 2nd Kunshan factory aluminum dust explosion accident]

Objective: To summarize the measures and experience of treatment in mass extremely severe burn patients. Methods: The clinical data and treatment of 8 extremely severe burn patients in August 2 Kunshan factory aluminum dust explosion accident who were admitted in the 100th Hospital of PLA on August 2nd, 2014, were retrospectively analyzed. There were 4 males and 4 females, aging 22-45 (34±7) years, with total burn area of 55%-98% [(89±15)%] total body surface area (TBSA) and full-thickness burn area of 45%-97% [(80±21)%] TBSA. All the 8 patients were accompanied with severe shock, inhalation injury, and blast injury. According to the requirements of former PLA General Logistics Department and Nanjing Military Command, a treatment team was set up including a special medical unit and a special care unit, with Chai Jiake from the First Affiliated Hospital of PLA General Hospital as the team leader, Zheng Qingyi from the 175th Hospital of PLA (the Affiliated Dongnan Hospital of Xiamen University) as the deputy leader, the 100th Hospital of PLA as the treatment base, and burn care, respiratory, nephrology, nursing specialists from the First Affiliated Hospital of PLA General Hospital, and the burn care experts and nursing staff from the 180th Hospital of PLA, 118th Hospital of PLA, 98th Hospital of PLA, and 175th Hospital of PLA, and nurses from the 85th Hospital of PLA, 455th Hospital of PLA, 101th Hospital of PLA, 113th Hospital of PLA as team members. Treatment strategies were adopted as unified coordination by the superior, unified responsibility of team leader, division of labor and cooperation between team members, and multidisciplinary cooperation led by department of burns. With exception of one patient who received deep vein catheterization before admission, the other 7 patients were treated with deep vein catheterization 0.5 to 3.0 hours after admission to correct hypovolemic shock as soon as possible. Eight patients received tracheotomy, and 7 patients were treated with mechanical ventilation by ventilator in protective ventilation strategy with low tide volume and low volume pressure to assist breathing. Fiberoptic bronchoscopy was done one to three times for all the 8 patients to confirm airway injuries and healing status. Escharectomy and Meek dermatoplasty in the extremities of all the 8 patients were performed 3 to 6 days after injury for the first time. Escharectomy, microskin grafting, and covering of large pieces of allogeneic skin on the trunks of 4 patients were performed 11 to 16 days after injury for the second time. The broad-spectrum antibiotics were uniformly used at first time of anti-infective therapy, and then the antibiotics species were adjusted in time. The balance of internal environment was maintained and the visceral functions were protected. One special care unit was on responsibility of only one patient. Psychological intervention was performed on admission. The rehabilitative treatment was started at early stage and in company with the whole treatment. Results: Acute renal injury occurred in 5 patients within 36 hours after injury and their renal function was restored to normal 4 days after injury due to active adjustment of fluid resuscitation program. No pulmonary complications, such as severe pulmonary infection and ventilator-associated pneumonia, occurred in the survived patients. One of the 8 patients died, and the other 7 patients were cured successfully. The wounds were basically healed in 2 patients in 26 or 27 days by 2 or 3 times of operation, and in 5 patients by 4 or 5 times of operation. The basic wound healing time was 26-64 (48±15) days for all the 7 patients. Conclusions: Treatment strategies of unified coordination by the superior, unified responsibility of team leader, division of labor and cooperation between team members, and multidisciplinary cooperation led by department of burns are the bases to successful treatment. Correcting shock as soon as possible is the prerequisite and closing wound as soon as possible is the key to successful treatment. Comprehensive treatment measures, such as maintaining and regulating the function of viscera, improving the body immunity, and preventing and treating the complications, are the important components to successful treatment. It is emphasized that in the treatment of mass extremely severe burn patients, specialist burn treatment should always be in the dominant position, and other related disciplines may play a part in auxiliary function.

[Clinical significance of bedside dynamic visual acuity test]

Objective: Dynamic visual acuity (DVA) is defined as the visual acuity when there are relative movements between subjects and visual targets. The purpose of this study was to discuss the correlation between bedside DVA test and other examinations of vestibular function, and to assess the value of DVA test for clinical diagnosis. Methods: Retrospective analysis of 323 cases with peripheral vestibular disorder, and analyzing the correlation between bedside DVA results and caloric test were performed. Results: Out of these 323 cases, 113 cases showed positive results of DVA.Among these 113 cases with positive DVA test, 109 cases were bilateral or unilateral vestibular function loss according to the results of caloric test or VEMP. The disease with the highest positive rate of DVA was bilateral vestibulopathy(BVP), followed by vestibular neuritis (VN) and profound sudden sensorineural hearing loss (pSSNHL). Conclusions: Bedside DVA is effective to determine the cases with BVP and severe unilateral vestibular function loss.

Estimation on Formation Time of Thrombus

OBJECTIVES

To observe the changes of the formation time of venous thrombus in rats, and to provide new ideas and methods for the estimation on thrombus formation time of the forensic cases died from thrombosis.

METHODS

Totally 80 rats were randomly divided into 10 groups （0 h, 3 h, 6 h, 12 h, 1 d, 3 d, 1 week, 2 weeks, 3 weeks and 4 weeks after operation）. A vein thrombosis model was established by the "narrow" method. The processes of thrombosis, organization, recanalization and the features of change on hemosiderin and calcium salt were observed by HE stain, Perls stain and Von Kossa stain. The expression changes of CD61, α-SMA and CD34 were observed by immunohistochemical staining technique.

RESULTS

Platelets adhered to the exposed blood vessel intima 3 h after operation, and platelet trabeculae were formed by the repeated accumulation of platelets 1 d after operation. The thrombus organization formed through the fibroblasts from vessel wall that grew into the interior of the thrombus 3 d after operation. Endothelial cells covered the surface of thrombus and then the new blood vessels were reformed, and the vessels were reconstructed. The expression of CD61 upregulated at the stages of the thrombus formation （3 h） and thrombus reformation （4 weeks）, and reached the peak 1 d after thrombus formation. The release of hemosiderin and the initial expression of α-SMA were detected 3 d later. Calcium deposit and expression of CD34 were observed 1 week later.

CONCLUSIONS

The hemosiderin, calcium salt, CD61, α-SMA and CD34 show time-dependent changing characteristics, which is expected to provide a reference for the estimation on thrombus formation time of the forensic cases died from thrombosis.

Considerations of the q-profile control in KSTAR for advanced tokamak operation scenarios

The q-profile control is essential for tokamaks exploring the advanced tokamak scenarios, which is expected to be able to provide a possible route toward a steady-state high performance operation in a fully non-inductive current drive state. This is because the pressure and current profiles must remain optimal for the scenario during the injection of large amounts of heating and current drive. Here, essential tools for the q-profile control are the motional Stark effect diagnostic for measuring the radial magnetic pitch angle profile and a state-of-the-art plasma control system. The pulse duration of the H-mode discharge at KSTAR has been extended year by year with improved control performance, and the experiment of internal transport barrier (ITB) formation in a weakly reversed q-profile with a marginal neutral beam injection majority heating successfully demonstrated that the ITB is an alternative candidate to achieve a high performance regime in KSTAR. These recent achievements are attributed to reliable profile measurement, which means that profile feedback control has become a necessary step to ensure a robust and reliable approach to advanced scenarios as the next step of research in KSTAR. In this paper, we discuss the technical and conceptual requirements for q-profile control according to the upgrade plan for heating and current drive systems in the coming years.

[High mechanical stretch stress promotes degeneration of the human nucleus pulposus cells through NF-κb signaling pathway]

Objective: To investigate the effect of high mechanical stretch stress(HMS)on human nucleus pulposus cells and its regulatory mechanism. Methods: The non-degenerated nucleus pulposus tissue (Pfirrmann<grade Ⅲ) removed from the patient's surgery was harvested and the human nucleus pulposus cells were isolated and cultured. In the presence or absence of pretreatment with the NF-κB specific blocker Bay11-7082, the cultured human nucleus pulposus cells were loaded cyclic mechanical stretch stress(CMS) with different parameters using the Flexercell system.The cell culture medium was collected and the secretion of inflammatory cytokines was detected by Elisa. The nucleus pulposus cells loaded with cyclic mechanical stretch stress(CMS) was collected, the changes of NF-κB/P65 signal pathway were detected, The mRNA and protein levels' expression changes were detected by RT-PCR and WB; after human nucleus pulposus cells were exposed to IL-1β, with or without Bay11-7082, the changes of P65 were detected by immunofluorescence. Results: Those mechanical stretch stress of high amplitude (9%, 19%), low frequency (0.01 Hz) and long duration (72 h) led to degeneration of human nucleus pulposus cells, while the mechanical stretch stress of low amplitude (3%), low frequency and long duration could not promote the degeneration process; the mechanical stretch stress of high amplitude(19%), low-frequency(0.01 Hz) could promote the release of inflammatory cytokines of human nucleus pulposus cells after 24 h duration; high-amplitude, low-frequency mechanical stretch stress could activate the NF-κB signaling pathway in human nucleus pulposus cells, Bay11-7082 could block the process; immunofluorescence showed that IL-1β could promote the phosphorylation of P65 in the cytoplasm of human nucleus pulposus cells and promote the entry of P65 into the cell nucleus process, Bay11-7082 could block those processes; Bay11-7082, the specific blocking agent of NF-κB signaling pathway, could block the degeneration process of human nucleus pulposus cells induced by high cyclic mechanical stretch stress(CMS) in a dose-dependent. Conclusions: High cyclic mechanical stretch stress promotes human nucleus pulposus cells degeneration through NF-κB signaling pathway.

[Research on the reliability and validity of postural workload assessment method and the relation to work-related musculoskeletal disorders of workers]

OBJECTIVE

To form a new assessment method to evaluate postural workload comprehensively analyzing the dynamic and static postural workload for workers during their work process to analyze the reliability and validity, and to study the relation between workers' postural workload and work-related musculoskeletal disorders (WMSDs).

METHODS

In the study, 844 workers from electronic and railway vehicle manufacturing factories were selected as subjects investigated by using the China Musculoskeletal Questionnaire (CMQ) to form the postural workload comprehensive assessment method. The Cronbach's α, cluster analysis and factor analysis were used to assess the reliability and validity of the new assessment method. Non-conditional Logistic regression was used to analyze the relation between workers' postural workload and WMSDs.

RESULTS

Reliability of the assessment method for postural workload: internal consistency analysis results showed that Cronbach's α was 0.934 and the results of split-half reliability indicated that Spearman-Brown coefficient was 0.881 and the correlation coefficient between the first part and the second was 0.787. Validity of the assessment method for postural workload: the results of cluster analysis indicated that square Euclidean distance between dynamic and static postural workload assessment in the same part or work posture was the shortest. The results of factor analysis showed that 2 components were extracted and the cumulative percentage of variance achieved 65.604%. The postural workload score of the different occupational workers showed significant difference (P<0.05) by covariance analysis. The results of nonconditional Logistic regression indicated that alcohol intake (OR=2.141, 95%CI 1.337-3.428) and obesity (OR=3.408, 95%CI 1.629-7.130) were risk factors for WMSDs. The risk for WMSDs would rise as workers' postural workload rose (OR=1.035, 95%CI 1.022-1.048). There was significant different risk for WMSDs in the different groups of workers distinguished by work type, gender and age. Female workers exhibited a higher prevalence for WMSDs (OR=2.626, 95%CI 1.414-4.879) and workers between 30-40 years of age (OR=1.909, 95%CI 1.237-2.946) as compared with those under 30.

CONCLUSION

This method for comprehensively assessing postural workload is reliable and effective when used in assembling workers, and there is certain relation between the postural workload and WMSDs.

[The study of the eosinophil CD34+ progenitor cells differentiation mechanism of model rats with occupational asthma and the intervention of warm and tonifying kidney yang decoction]

Objective: To investigate the mechanism of CD34⁺ progenitor cell differentiation in rat by observing the change relations between the eosinophils (EOS) and the content of Eotaxin and IL-5 in blood and the CD34⁺/CCR3⁺, CD34⁺/IL-5Rα+ in bone marrow after occupational asthma (OA) model rats are simulated, and to observe the effect of WTKYD Trraitional Chinese Medicine intervention. Methods: A total of 40 healthy male SD model rats (200~250 g weight) were randomly divided into model contrast Group, prednisone acetate intervention Group, WTKYD+1/2 prednisone acetate intervention Group and WTKYD intervention Group, 10 in each group, and set a Group for blank contrast. Give them saline (20 ml/kg) , prednisone acetate (8.22 mg/kg) , WTKYD (20g/kg) +1/2 prednisone acetate (4.11 mg/kg) and WTKYD (20 g/kg) intervention respectively. By means of cell count, immunohistochemical, ELISA, flow cytometry technique, situ hybridization and so on, to observe EOS and the expression of Eotaxin in lung tissue, the EOS in peripheral blood, the content of Eotaxin and IL-5 in blood as well as the expression of CD34⁺/CCR3⁺ and CD34⁺/IL-5Ra⁺ in bone marrow respectively. Results: The number of EOS, the content of Eotaxin and IL-5, the expression of CD34⁺/CCR3⁺ and CD34⁺/IL-5Ra+ in Model Contrast Group were higher in Blank Contrast Group, the difference was statistically significant (P<0.01) , while they were lower in medical intervention Groups when comparing to Model Contrast Group, the difference was statistically significant (P<0.01 or P<0.05) , and the above items in WTKYD+1/2 Prednisone Acetate Intervention Group were even lower than in Prednisone Acetate Intervention Group and WTKYD Intervention Group, the difference was statistically significant (P<0.05). EOS in lung tissue is highly positive related to the content of Eotaxin and IL-5 in peripheral blood as well as the expression of CD34⁺/CCR3 and CD34⁺/IL-5Rα in bone marrow (0.9666、0.9829、0.9142, 0.8874). Conclusion: The increase of internal EOS in lung tissue is related to the up-regulated expression of CD34⁺/CCR3⁺ and CD34⁺/IL-5Ra⁺ in bone marrow after antigens in Occupational Asthma model rats are stimulated. Through down-regulating it's expression to restrain the differentiation of CD34⁺ progenitor cells towards EOS, meanwhile, the collaboration of WTKYD and prednisone acetate possess a certain synergistic action.

[Anterior cervical discectomy and fusion to treat cervical spondylosis with sympathetic symptoms]

OBJECTIVE

To investigate the clinical effectiveness of polytheretherketone (PEEK) cages assisted anterior cervical discetomy and fusion (ACDF) to treat cervical spondylosis with sympathetic symptoms.

METHODS

Retrospective analysis was undertaken for 39 patients who were diagnosed as cervical spondylosis with sympathetic symptoms and underwent ACDF with PEEK cages. Radiographs obtained before surgery, after surgery, and at the final follow-up were assessed for quality of fusion. The following criteria were used for assessing radiographic success of fusion: (1) endplate obliterated with no lucent lines; (2) obliteration of disc space by bony trabeculae; (3) less than 2°of intervertebral motion or 2 mm of motion between the spinous processes at the operated segment on flexion-extension lateral radiographs. The sympathetic symptoms including vertigo, headache, tinnitus, nausea and vomiting, heart throb, hypomnesia and gastroenterological discomfort were scored by 20-point system preoperatively, 2 months postoperatively and at the final follow-up. The recovery rate and clinical satisfaction rate were also evaluated. Surgical complications were also assessed.

RESULTS

They were followed up for at least one year. The mean follow-up was 15.6 months. Radiographs of the cervical spine at the last follow-up revealed a solid fusion with no signs of a pseudoarthrosis in 36 cases. In two patients delayed union and bony fusion were achieved at the end of 9 and 11 months. Pseudoarthosis was found in 1 case but the patient had no symptoms. The score of sympathetic symptoms before surgery, 2 months after surgery and at the final follow-up were 8.4±1.0,2.2±0.3,and 2.4±0.3, respectively. There were 22 excellent cases, 15 good cases, 1 fair case and 1 bad case in terms of RR. Good to excellent results were attained in 95% of theses patients. The sympathetic symptoms improved in all the patients and the score was significantly improved after surgery. There was one patient who had cerebral spinal fluid leakage but he recovered one week after surgery. Two patients felt a mild swallowing discomfort, but it disappeared within one month after surgery. Subcutaneous hematoma occurred in one patient due to obstructed drainage. It was cleared two days after surgery.

CONCLUSION

Cervical spondylosis patients with sympathetic symptoms may be managed successfully with ACDF using PEEK cages. Successful clinical results regarding symptom improvement and general satisfaction with the surgical procedure depend not only on obtaining successful decompression and radiographic fusion but also on patient selection.

[Gene expression profiles of long non-coding RNAs in human degenerated intervertebral disc tissue]

Objective: To investigate the gene expression profiles of long non-coding RNAs (lncRNA)in human degenerated intervertebral disc degeneration (IDD). Methods: An lncRNA-mRNA microarray analysis of human nucleus pulposus (NP) was employed. Bioinformatics prediction was also applied to delineate the functional roles of the differentially expressed lncRNAs. Several lncRNAs and mRNAs were chosen for quantitative real-time PCR (qRT-PCR) validation. Results: A total of 1 570 lncRNAs expressed in degenerate group compared with the nondegenerate group. Of these, the expression level of 428 lncRNAs was upregulated >2-fold compared with nondegenerate group while that of 584 was downregulated. Bioinformatics analysis (GO and pathway analyses) revealed that some classical pathways participating in extracellular matrix (ECM) and cell apoptosis were aberrantly expressed in the intervertebral disc (P<0.05). Enhancer-like lncRNAs and their nearby coding genes were analyzed. Three lncRNAs were identified as potential enhancers. Several lncRNAs were validated in the intervertebral disc using RT-qPCR. Conclusion: The lncRNAs express differentially in the intervertebral disc. LncRNAs may therefore be novel candidate biomarkers and potential targets for intervertebral disc degeneration therapy in the future.

[Human exposure and thyroid toxicity of polybrominated diphenyl ethers]

Polybrominated diphenyl ethers (PBDEs), a kind of important Brominated Flame Retardant (BFR), are widely used in electronic products, construction materials and textiles. PBDEs have been detected in many environmental media (including air, water, dust, sediment and food), many animal and human tissues. For their environmental persistence, high bioaccumulative and multiple biotoxicitiies, PBDEs have been viewed as one of the most concerned environmental Endocrine Disrupting Chemicals (EDCs) at present. Although detailed mechanisms are not clear, studies have found that PBDEs can induce toxicity to liver, endocrine system, nervous system, reproduction and immune system. What's more, lots of experiments indicate that PBDEs exposure can alter the levels of thyroid hormones. Recently, studies on the impact of PBDEs exposure on thyroid hormones have been quite a few and have not reached an agreement, especially on the alternation of thyroid hormones caused by PBDEs exposure, which has also been a hot issue. This paper reviews from the basic properties, usage, exposure and biotoxicity of PBDEs. We mainly introduce the impact PBDEs have on the thyroid and thyroid hormones in terms of biotoxicity, and attach importance to the endocrine disruption and neurodeveloptoxicity. We also give a preliminary introduction to hydroxylated and methoxylated polybrominated diphenyl ethers, structural analogs of PBDEs, which researchers start late to study. This paper can be a reference for the further research on PBDEs exposure and biotoxicity.

[Effects of combined application of culture supernatant of human umbilical cord mesenchymal stem cells and ciprofloxacin on Staphylococcus aureus in vitro]

Objective: To explore the effects of combined application of culture supernatant of human umbilical cord mesenchymal stem cells (hUCMSCs) and ciprofloxacin on Staphylococcus aureus (SA) in vitro. Methods: hUCMSCs were isolated from umbilical cord tissue of full-term healthy fetus after cesarean section and cultured. Cells in the third passage were used in the experiments after identification. SA strains isolated from wounds of burn patients in our burn wards were used in the experiments. Cells were divided into 0, 10, 100, and 1 000 ng/mL lipopolysaccharide (LPS) groups according to the random number table (the same dividing method below). Cells were cultured with culture medium of mesenchymal stem cells (MSCs) after being treated with medium containing the corresponding mass concentrations of LPS for 12 h. At post culture hour (PCH) 6, 12, and 24, 6 wells of culture supernatant of cells in each group were obtained to measure the content of LL-37 with enzyme-linked immunosorbent assay. Ninety blood agar plates were divided into ciprofloxacin control group (CC), ciprofloxacin+ supernatant group (CS), and ciprofloxacin+ supernatant+ LL-37 antibody group (CSL), with 30 blood agar plates in each group. Blood agar plates in group CC were coated with 1.5×10(8) colony forming unit (CFU)/mL bacteria solution prepared with normal saline. Blood agar plates in group CS were coated with 1.5×10(8) CFU/mL bacteria solution prepared with normal saline and culture supernatant of hUCMSCs (cultured by culture medium of MSCs, the same below) in double volume of normal saline. Blood agar plates in group CSL were coated with 1.5×10(8) CFU/mL bacteria solution prepared with normal saline, culture supernatant of hUCMSCs in double volume of normal saline, and 2.6 μL LL-37 antibody in the concentration of 2 μg/mL. At PCH 12, 24, and 48, 10 blood agar plates of each group were harvested to observe the distribution of SA colony on blood agar plate and to measure the diameter of bacterial inhibition ring of ciprofloxacin. The minimum inhibitory concentration (MIC) of ciprofloxacin against SA of each group was recorded. Fractional inhibitory concentration (FIC) indexes of ciprofloxacin in groups CS and CSL at PCH 12, 24, and 48 were calculated, and the effect of synergy was evaluated. Data were processed with analysis of variance of factorial design, one-way analysis of variance, LSD-t test, Kruskal-Wallis test, and Mann-Whitney U test. Results: (1) At each PCH, the content of LL-37 in culture supernatant of cells in 10, 100, and 1 000 ng/mL LPS groups was higher than that in 0 ng/mL LPS group (with t values from 11.22 to 33.36, P values below 0.01); the content of LL-37 in culture supernatant of cells in 100 and 1 000 ng/mL LPS groups was higher than that in 10 ng/mL LPS group (with t values from 2.24 to 18.73, P<0.05 or P<0.01); the content of LL-37 in culture supernatant of cells in 1 000 ng/mL LPS group was higher than that in 100 ng/mL LPS group (with t values from 12.46 to 14.70, P values below 0.01). (2) At PCH 12, 24, and 48, the bacterial colonies in groups CC, CS, and CSL began to integrate over time. At PCH 12, 24, and 48, the diameters of bacterial inhibition ring of ciprofloxacin in group CC were 26, 24, and 23 mm, respectively, with no obvious change. At PCH 12, 24, and 48, the diameters of bacterial inhibition ring of ciprofloxacin in groups CS and CSL were 82, 71, 68 mm, and 74, 59, 56 mm, respectively, significantly longer than those of group CC. (3) At each PCH, the MIC of ciprofloxacin against SA was significantly higher in group CC than in groups CS and CSL (with Z values from 6.22 to 6.71, P values below 0.01); the MIC of ciprofloxacin against SA was significantly higher in group CSL than in group CS (with Z values all equal to 6.72, P values below 0.01). (4) FIC indexes of ciprofloxacin in groups CS and CSL at PCH 12, 24, and 48 were 0.011, 0.032, 0.032, and 0.122, 0.350, 0.350, respectively. The results indicated that culture supernatant of hUCMSCs had synergistically antibacterial effect on ciprofloxacin. Conclusions: hUCMSCs can secrete LL-37, and the secretion level is increased with increase of LPS concentration. Combination of culture supernatant of hUCMSCs and ciprofloxacin can decrease the dosage of ciprofloxacin in resisting SA. Once LL-37 is neutralized, the synergistically antibacterial effect of culture supernatant of hUCMSCs is decreased.

[Clinical analysis of 21 cases with short fetal femur in the third trimester]

Objective: To analyze the clinical features and to explore the etiology of short fetal femur during the third trimester. Methods: From January 2010 to June 2016, 21 singleton pregnancies with short fetal femur detected by ultrasonography during the third trimester were referred to the Chinese PLA General Hospital. Clinical data were collected, karyotype or single nucleotide polymorphism microarray was carried out to detect chromosomal abnormalities, and FGFR3 c.1138G>A mutation detection was carried out to detect achondroplasia (ACH) via invasive procedure, respectively. The deviation of femur length from the mean value of the gestational age in ultrasonography was expressed as the Z-score. The difference between ACH and isolated short femur (ISF, in the absence of associated structure abnormality or genetic abnormality) was then explored. Results: In the 21 fetuses, 11 had abnormal genetic test results(52%, 11/21), including 9 cases of ACH, 1 case of Ellis-van Creveld Syndrome and 1 case of Pallister-Killian syndrome. In the 10 ISF fetuses (48%, 10/21), 3 cases were fetal growth restriction, 1 was normal small for gestational age infant and 6 cases were unexplained. The median Z-scores for 9 cases of ACH and 10 cases of ISF in the third trimester were -5.04, -3.20, respectively. The short femur in ACH was more severe than in ISF (P=0.005) in the third trimester. Conclusions: The etiology of short fetal femur is complicated, including skeletal dysplasia, chromosomal abnormality, fetal growth restriction, as well as normal variants during fetal development. Genetic test should be considered during the antenatal consultation.