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Acupuncture is ineffective for chronic low back pain? A critical analysis and rethinking

Xuqiang Wei, Baoyan Liu

《医学前沿（英文）》 2021年第15卷第5期页码 767-775 doi: 10.1007/s11684-020-0785-6

摘要： Acupuncture is a promising treatment for relieving pain and improving lower back function in clinical practice. However, evidence from randomized clinical trials (RCTs) remains controversial. Most RCTs conclude that acupuncture procedures for chronic low back pain (CLBP) had no significant difference in efficacy and belonged to placebo. We carefully reviewed and analyzed the methodology and implementation of sham acupuncture in RCTs. Controversial evidence of acupuncture for CLBP is only a microcosm of the evaluation methodological limitation of acupuncture. Inappropriate selection of sham acupuncture controls, rigorous RCT research models, and incorrect interpretation of results may contribute to negative evidence. Evaluating and disregarding the holistic efficacy of acupuncture with an explanatory RCT model based on evaluation drugs may be unwise. Moreover, sham acupuncture is often proven to be non-inert, unreasonable, and with low fidelity. Pitfalls of the explanatory RCT model and sham acupuncture design should be avoided. Establishing a new evaluation system that is in line with the clinical characteristics of acupuncture and obtaining high-quality evidence are difficult but promising tasks.

关键词： chronic low back pain sham acupuncture acupuncture methodology therapeutic evaluation

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《医学前沿（英文）》 2015年第9卷第3期页码 374-379 doi: 10.1007/s11684-015-0411-1

摘要：

This study aimed to determine the relationship between the different factors of analgesic therapy and the compliance of chronic pain inpatients. We prospectively investigated 100 consecutive inpatients with non-cancer chronic pain who were hospitalized to receive oral analgesic treatment in the Pain Department of West China Hospital from May 2013 to October 2013. Patients who completed the treatment plan were recorded as good compliance, whereas patients who partly completed or even refused the treatment were recorded as moderate or non-compliance, respectively. A total of 73 (73.7%), 17 (17.1%), and 9 (9.2%) patients showed good, moderate, and non-compliance, respectively. Univariate analyses showed significantly better compliance among farmers, patients educated in college or above, with family income of<3000 CNY, and with severe or moderate pain than those employed and unemployed (P=0.02), patients educated below college (P=0.013), with family income of≥3000 CNY (P=0.025), and with mild pain (P<0.001), respectively. Logistic regression analysis showed that the family income of≥3000 CNY (OR: 2.50, 95%CI: 1.65–4.51, P=0.021) and mild pain (OR: 1.27, 95%CI: 1.03–3.31, P=0.016) were associated with moderate or non-compliance with oral analgesic treatment. In conclusion, the low compliance with oral treatment of analgesics was found in Chinese inpatients with chronic pain and compliance was negatively associated with family income and degree of pain of patients.

关键词： chronic pain inpatient oral paregoric drugs compliance

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Efficacy and safety of perioperative parecoxib for acute postoperative pain treatment in children: a

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《医学前沿（英文）》 2015年第9卷第4期页码 496-507 doi: 10.1007/s11684-015-0414-y

摘要：

Perioperative parecoxib administration reduces postoperative pain, opioid consumption, and adverse events in adult patients. However, the efficacy and safety of parecoxib in children remain unclear. This meta-analysis included related published studies to address this concern. Eight databases in the literature until February 2015 were systematically explored to identify randomized controlled trials (RCTs) comparing perioperative parecoxib administration and placebo/standard treatments for acute postoperative pain in children. Primary outcomes were postoperative pain scores and adverse events. The Face, Legs, Activity, Crying, Consolability scale was used to score pain in children younger than 6 years, whereas the Visual Analog Scale was used in children older than 6 years. Secondary outcomes were sedation scores (measured using the Ramsay scale), agitation scores (measured using the Sedation-Agitation Scale), and opioid consumption. The methodological quality of RCTs was independently assessed in accordance with the “Risk of bias” of Cochrane Collaboration. Data were analyzed using Review Manager 5.2. Twelve RCTs involving 994 patients met the inclusion criteria. Compared with children who received placebo treatment, those who received parecoxib demonstrated lower early (2 h) and later (12 h) postoperative pain scores; lower incidence rates of postoperative nausea, vomiting, and agitation; higher early (1 h) postoperative sedation scores; and lower agitation scores. Similarly, children who received parecoxib had lower early (2 h) and later (12 h) postoperative pain scores, lower incidence rates of postoperative nausea and vomiting, and lower early (1 h) postoperative sedation scores compared with those who received standard treatments; however, these children showed no significant difference in agitation scores. Unfortunately, data on the effect of parecoxib on opioid consumption were insufficient. Overall, these results suggested that perioperative parecoxib administration was associated with less acute postoperative pain and fewer adverse events compared with placebo or standard treatments. Parecoxib administration also resulted in less emergence agitation compared with placebo treatment and less excessive sedation concern compared with standard treatments. However, the long-term effects, effects on opioid consumption, and patient satisfaction of parecoxib administration warrant further investigation.

关键词： NSAID cyclooxygenase 2 inhibitor child pain postoperative opioid placebo

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Discussion on back-to-back two-stage centrifugal compressor compact design techniques

Lei HUO, Huoxing LIU

《机械工程前沿（英文）》 2013年第8卷第4期页码 390-400 doi: 10.1007/s11465-013-0278-2

摘要：

Design a small flow back-to-back two-stage centrifugal compressor in the aviation turbocharger, the compressor is compact structure, small axial length, light weighted. Stationary parts have a great influence on their overall performance decline. Therefore, the stationary part of the back-to-back two-stage centrifugal compressor should pay full attention to the diffuser, bend, return vane and volute design. Volute also impact downstream return vane, making the flow in circumferential direction is not uniformed, and several blade angle of attack is drastically changed in downstream of the volute with the airflow can not be rotated to required angle. Loading of high-pressure rotor blades change due to non-uniformed of flow in circumferential direction, which makes individual blade load distribution changed, and affected blade passage load decreased to reduce the capability of work, the tip low speed range increases.

关键词： back-to-back two-stage centrifugal compressor design Internal flow

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Spray characteristics of high-pressure swirl injector fueled with alcohol

WANG Xibin, CHEN Wansheng, GAO Jian, JIANG Deming, HUANG Zuohua

《能源前沿（英文）》 2007年第1卷第1期页码 105-112 doi: 10.1007/s11708-007-0012-z

摘要： The spray characteristics of methanol and ethanol with high-pressure swirl injector were explored experimentally and numerically. Experimental results show that the spray characteristics of methanol and ethanol had displayed the same trends as that of gasoline. Under the low back-pressure ambient conditions, the spray behavior exhibited a hollow cone with wide spray angle and initial spray slug at the tip, while the spray presented a solid cone in the case of high back-pressure. Vortexes in the opposite direction existed in the rear part of the spray under low back-pressure ambient conditions while the vortexes formed in the middle part under high back-pressure ambient conditions. Experiments also showed that methanol had the largest cone angle, while ethanol and gasoline presented almost the same cone angle. Simulation results indicated that methanol and ethanol had a slightly larger Sauter mean diameter (SMD) than that of gasoline with swirl injector. The SMD profile of methanol coincided well with that of ethanol under low back-pressure ambient conditions, but displayed a slightly larger value under high back-pressure due to fuel evaporation. Numerical simulation could successfully demonstrate the spray characteristics of high-pressure swirl injector for methanol and ethanol fuels.

关键词： low back-pressure diameter initial spray hollow middle

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Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

《能源前沿（英文）》 2016年第10卷第2期页码 213-226 doi: 10.1007/s11708-016-0398-6

摘要： There is a considerable number of works devoted to electrical characteristics of grounding. These characteristics are important in general. However, in application to grounding of transmission line towers they are not enough to determine what grounding construction is preferable in some particular case, because these characteristics are calculated or measured apart from the grounded object, and only limited number of current (or voltage) source waveforms is used. This paper indicates reasons in favor of the fact that to choose the optimum design of grounding, the calculation model should include the tower as it is. The probability of back flashover, which provides both qualitative and quantitative estimate of the grounding structure efficiency, can be taken as the criterion for the grounding design. The insulation flashover probability is calculated on the basis of engineering method, which evaluates breakdown strength of insulation for nonstandard waveshapes, and probability data on lightning currents. Different approaches are examined for identifying the back flashover probability, as not only amplitudes but also other parameters can be taken into account. Finite-difference time-domain method is used for calculations of transients. It is found that lightning current waveform can greatly influence calculated back flashover probability value.

关键词： grounding transmission line tower back flashover probability FDTD method

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DFIG sliding mode control fed by back-to-back PWM converter with DC-link voltage control for variable

Youcef BEKAKRA,Djilani BEN ATTOUS

《能源前沿（英文）》 2014年第8卷第3期页码 345-354 doi: 10.1007/s11708-014-0330-x

摘要： This paper proposes an indirect power control of doubly fed induction generator (DFIG) with the rotor connected to the electric grid through a back-to-back pulse width modulation (PWM) converter for variable speed wind power generation. Appropriate state space model of the DFIG is deduced. An original control strategy based on a variable structure control theory, also called sliding mode control, is applied to achieve the control of the active and reactive power exchanged between the stator of the DFIG and the grid. A proportional-integral-(PI) controller is used to keep the DC-link voltage constant for a back-to-back PWM converter. Simulations are conducted for validation of the digital controller operation using Matlab/Simulink software.

关键词： doubly fed induction generator (DFIG) wind turbine back-to-back pulse width modulation (PWM) DC-link voltage sliding mode control

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New perspective on the natural course of chronic HBV infection

null

《医学前沿（英文）》 2014年第8卷第2期页码 129-134 doi: 10.1007/s11684-014-0339-x

摘要：

Chronic hepatitis B virus (HBV) infection is a significant threat to public health and an enormous burden on society. Mechanisms responsible for chronic HBV infection remain poorly understood. A better understanding of the natural course of chronic HBV infection may shed new light on the mechanisms underlying this disease and help in designing new antiviral strategies. Natural course of chronic HBV infection is conventionally viewed as an uninterrupted process that is usually marked by HBV e antigen (HBeAg) seroconversion or characterized by different phases associated with assumed host responses to HBV infection. However, none of these descriptions captures or highlights the core events that determine the natural course of chronic HBV infection. In this review, we briefly present the current knowledge on this subject and explain the significance and implication of events that occur during infection. A pre-core mutant becomes predominant in the viral population following elimination of the wild-type virus in duck hepatitis B virus-chronically infected animals. The coupled events in which first there is viral clearance that clears wild-type virus and then there is the reinfection of wild-type virus cleared livers with mutant virus are highly relevant to understanding of the natural course of chronic HBV infection under both treated and untreated conditions. In our new perspective, a general natural course of chronic HBV infection comprises cycles of viral clearance and reinfection, and such cycles prolong the chronic HBV infection course. Reviewing published data on the natural course of chronic HBV infection can reduce the possibility of missing important points in the initial data interpretation.

关键词： hepatitis B virus chronic HBV infection natural course hepatitis B seroconversion

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Renewable synthetic fuel: turning carbon dioxide back into fuel

《能源前沿（英文）》 2022年第16卷第2期页码 145-149 doi: 10.1007/s11708-022-0828-6

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Effect of renal function and hemodialysis on the serum tumor markers in patients with chronic kidney

YU Xiaofang, XU Xialian, YE Zhibin

《医学前沿（英文）》 2007年第1卷第3期页码 308-311 doi: 10.1007/s11684-007-0059-6

摘要： In patients with chronic renal failure, whether they have had hemodialysis or not, the specificity of some of the serum tumor markers for the diagnosis of the corresponding tumors is decreased while others remain as valuable as they are in patients with normal kidney function. The detection of tumor markers is extensively used for the diagnosis of corresponding tumors. It has been recently shown that some tumor markers are higher in patients with chronic kidney disease (CKD) than in the normal population. The effects of renal function and hemodialysis were examined on serum levels of some of the tumor markers including CEA, CA, CA, AFP, CA, CA, CYFRA, NSE, SCC-Ag, PSA, and fPSA. The 232 non-dialysis patients with CKD and 37 chronic uremic patients treated with maintenance hemodialysis were enrolled in this study. The 232 non-dialysis patients were divided into three groups according to their Ccr. In group 1, Ccr was ≤25 mL/min. In group 2, Ccr was between 25 and 50 mL/min. In group 3, Ccr was ≥50 mL/min. The male patients were also divided into three groups to compare the serum levels of PSA and fPSA among the three groups. Nine tumor markers in 37 uremic patients were tested. For comparison, 37 non-dialysis patients with similar Ccr of the same age and gender served as controls. There existed significant differences in serum levels of CEA, CA, CYFRA, NSE, and SCC-Ag among different Ccr groups and the markers bore a negative correlation with Ccr. There were no significant differences among the three groups in the serum concentrations of CA, AFP, CA, CA, PSA and fPSA. The serum levels of CA and NSE were significantly higher (199, CYFRA, NSE, CA and SCC-Ag for the diagnosis of the corresponding tumors was decreased while serum AFP, CA, CA, PSA and fPSA were as valuable as they were in patients with normal kidney function. Hemodialysis further increased the serum level of CA and NSE.

关键词： CKD non-dialysis valuable detection chronic

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Vaccine therapies for chronic hepatitis B: can we go further?

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《医学前沿（英文）》 2014年第8卷第1期页码 17-23 doi: 10.1007/s11684-014-0313-7

摘要：

Chronic hepatitis B is a major health burden worldwide. In addition to the recent progress in antiviral treatment, therapeutic vaccination is a promising new strategy for the control of chronic hepatitis B. On the basis of the major specific and non-specific immune dysregulations and defects in chronic hepatitis B patients, this paper presents the peptide and protein-based, DNA-based, cell-based, and antigen-antibody-based therapeutic vaccines, which have undergone clinical trials. The advantages, disadvantages, and future perspectives for these therapeutic vaccines are discussed.

关键词： chronic hepatitis B therapeutic antigen-antibody complexes DNA vaccine

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Perceived resource support for chronic illnesses among diabetics in north-western China

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《医学前沿（英文）》 2016年第10卷第2期页码 219-227 doi: 10.1007/s11684-016-0441-3

摘要：

A high level of social support can improve long-term diabetes self-management. Support from a single source has been evaluated. This study aims to analyze support from multiple and multilevel sources for diabetic patients by using the Chronic Illness Resources Survey (CIRS). Factors influencing the utilization of the CIRS were also evaluated. A total of 297 patients with diabetes were investigated using the CIRS and Perceived Diabetes Self-management Scale in Shihezi City, China. Descriptive statistics were used to explain demographic variables and scores of the scales. Factors affecting the utilization of chronic illness resources were determined through univariate analysis and then examined by multivariate logistic regression analysis. Of the 297 diabetic patients surveyed, 67% failed to reach the standard (more than 3 points) of utilizing chronic illness resources. Moreover, utilization of chronic illness resources was positively moderately correlated with self-management of diabetes (r = 0.75, P <0.05). According to the multivariate logistic regression analysis, age (OR, 3.42; 95%CI, 1.19–9.84) and monthly income (OR, 5.27; 95%CI, 1.86–14.90) were significantly positively associated with the CIRS score. Individuals with high school (OR, 2.61; 95%CI, 1.13–6.05) and college (OR, 3.02; 95%CI, 1.13–8.04) degrees obtained higher scores in the survey than those with elementary school education. Results indicated that utilization of resources and support for chronic illness self-management, particularly personal adjustment and organization, were not ideal among diabetics in the communities of north-western China. Improved utilization of chronic illness resources was conducive for proper diabetes self-management. Furthermore, the level of utilization of chronic illness resources increased with age, literacy level, and monthly income.

关键词： chronic illness resources survey diabetes community north-western China

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Take back and treatment of discarded electronics: a scientific update

Ab STEVELS, Jaco HUISMAN, Feng WANG, Jinhui LI, Boyang LI, Huabo DUAN

《环境科学与工程前沿（英文）》 2013年第7卷第4期页码 475-482 doi: 10.1007/s11783-013-0538-8

摘要： This paper indicates that the performance of tack-back and treatment of electronic waste (e-waste) system can be improved substantially. This can be reached by better taking into account in a better way the big variety in material composition and potential toxicity of electrical and electronic products – from a technical, organizational and regulatory perspective. Realizing that there is no ‘one size fit for all’ and combining smart tailor made solutions with economic of sale will result in the best environmental gain/cost ratio. Several examples show how science and engineering have supported or will support this approach.

关键词： e-waste take back treatment substantially

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Correlation between viral load and liver cirrhosis in chronic hepatitis B patients

Lili LIU MM , Jiyao WANG MD , Weimin SHE MM ,

《医学前沿（英文）》 2009年第3卷第3期页码 271-276 doi: 10.1007/s11684-009-0054-1

摘要： The aim of this paper is to investigate the relationship between hepatitis B virus (HBV) DNA levels during the course and the progression to cirrhosis with chronic hepatitis B. A total of 239 chronic hepatitis B patients confirmed by liver biopsy between 2001 and 2007 were followed up for a median of 28 months. Compared with the patients without cirrhosis, the patients progressed to cirrhosis were older and with higher HBV-DNA levels at end point. However, there was no significant difference in cirrhosis progression between different HBV-DNA groups at baseline ( = 0.531). Kaplan-Meier analysis showed higher HBV-DNA level at endpoint had increasing risk of cirrhosis ( = 0.019). The results of Cox model indicated that HBV-DNA levels at endpoint, stage of fibrosis, negative hepatitis B e antigen, and γ-glutamyl transpeptidase at baseline were independent risk factors of cirrhosis. The relative risk ratios were 1.898, 1.918, 8.976, and 1.006, respectively. Progression to cirrhosis in chronic hepatitis B patients is correlated with HBV-DNA levels during follow-up.

关键词： hepatitis B chronic viral load liver cirrhosis