The casual effects of COVID-19 lockdown on air quality and short-term health impacts in China.

The outbreak of coronavirus (COVID-19) has forced China to lockdown many cities and restrict transportation, industrial, and social activities. This provides a great opportunity to look at the impacts of pandemic quarantine on air quality and premature death due to exposure to air pollution. In this study, we applied the difference-in-differences (DID) model to quantify the casual impacts of COVID-19 lockdown on air quality at 278 cities across China. A widely used exposure-response function was further utilized to estimate the short-term health impacts associated with changes in PM2.5 due to lockdown. Results show that lockdown has caused drastic reduction in air pollution level in terms of all criteria pollutants except ozone. On average, concentrations of PM2.5, PM10, NO2, SO2 and CO are estimated to drop by 14.3 µg/m3, 22.2 µg/m3, 17.7 µg/m3, 2.9 µg/m3, and 0.18 mg/m3 as the result of lockdown. Cities with more confirmed cases of COVID-19 are related to stronger responses in air quality, despite that similar lockdown measures were implemented by the local governments. The improvement of air quality caused by COVID-19 lockdown in northern cities is found to be smaller than that of southern cities. Avoided premature death associated with PM2.5 exposures over the 278 cities was estimated to be 50.8 thousand. Our results re-emphasize the effectiveness of emission controls on air quality and associated health impacts. The high cost of lockdown, still high level of air pollution during lockdown and smaller effects in northern cities implies that source-specific mitigation policies are needed for continuous and sustainable reduction of air pollution.

Effect of bone mineral density on the clinical efficacy of oblique lateral interbody fusion in the treatment of lumbar degenerative spondylolisthesis / 中国脊柱脊髓杂志

Objectives:To analyze the clinical effect of bone mineral density(BMD)on the efficacy of oblique lateral interbody fusion(OLIF)in the treatment of lumbar degenerative spondylolisthesis(LDS).Methods:A retrospective analysis was conducted on the clinical data of patients with Meyerding grade Ⅰ LDS who underwent OLIF assisted with a minimally invasive spinal channel system between December 2017 and July 2020.Based on the preoperative BMD,the patients were divided into low bone mass group(-2.5＜T-score＜-1.0,n=30)and osteoporosis group(T-score≤-2.5,n=22).There was no statistical difference between the two groups in gender ratio,age,and segments of spondylolisthesis(P＞0.05).The operative time,intraopera-tive blood loss,ambulation time after surgery,length of hospital stay,and complications were collected and compared between the two groups.The postoperative 1 week reduction rate of spondylolisthesis,and postoper-ative 1 month improvement in spinal canal cross-sectional area,and intervertebral disc height restoration were counted and compared;Bone graft fusion was observed of the two groups of patients on X-ray images at 3 months,6 months,and 12 months of follow-up after operation.The Japanese Orthopaedic Association(JOA)scores were assessed at pre-operation,and 1,3,6 and 12 months after operation,and JO A score at 12 months after operation was used to determine the improvement rate of JOA score.Results:Comparing with the osteoporosis group,the low bone mass group was shorter in operative time(119.5±12.7min vs.163.3± 14.2min),less in intraoperative blood loss(98.9±22.4mL vs.211.5±29.8mL),shorter in ambulation time after surgery(2.3±0.9d vs.3.9±1.2d)and length of hospital stay(6.2±1.3d vs.8.9±1.6d)(P＜0.05).At 1 week postoper-atively,complete reduction was observed in 29 cases(96.7％)in the low bone mass group and 15 cases(68.2％)in the osteoporosis group.There was a statistically significant difference in the reduction outcomes between the two groups(P＜0.05).After OLIF treatment,statistically significant differences were noted between the postopera-tive dural sac cross-sectional area and the intervertebral disc height and the preoperative values,respectively(P＜0.05).The recovery of intervertebral disc height of the osteoporosis group was significant different from that of the low bone mass group(12.79±0.99mm vs.11.25±0.98mm,P＜0.05),while the improvement of the dural sac cross-sectional area was not(P＞0.05).The fusion rates were not significantly different between the two groups(93.3％vs 77.3％,P＞0.05).The JOA scores at 1 month and 3 months after surgery in the low bone mass group were statistically significant different from those of the osteoporosis group(P＜0.05),while the JOA scores at 6 and 12 months after surgery were not significantly different between the two groups(P＞0.05).Conclusions:OLIF can achieve satisfactory short-term clinical outcomes in low bone mass and osteoporosis LDS patients,and its efficacy is better in patients with low bone mass than patients with osteoporosis.

Clinical effect of free fibular flap without vein of great toe in repairing soft tissue defect of finger pulp / 中华显微外科杂志

Objective:To investigate the clinical effect of free fibular flap of great toe without vein in repairing soft tissue defect of finger pulp.Methods:From June 2020 to January 2021, 8 cases of finger pulp soft tissue defect were repaired with free flap of fibular side of great toe without vein, including 6 males and 2 females, with an average age of 32(18-42) years old. The defect area of finger pulp was 1.0 cm×0.5 cm-1.8 cm×0.8 cm. The proper digital artery and digital nerve of the affected finger were anastomosed. All flaps did not carry reflux veins. The donor site of the toe was directly sutured. Postoperative routine anti infection, anti spasm and anticoagulant treatment was performed. Postoperative outpatient regular follow-up.Results:All flaps survived without vascular crisis, and the donor and recipient sites healed in the first stage. All patients were followed-up for an average of 6.4(4-12) months. At the last follow-up, the TPD was 6-8 mm, the hand function was evaluated according to the Trial Standard of Upper Limb Function Evaluation of Hand Surgery Society of Chinese Medical Association. Seven cases were excellent and 1 case was good.Conclusion:The free fibular flap of the great toe can be used to repair the small wound of finger pulp without carrying the draining vein, the flap can still survive. And it can provide a certain reference for the failure of anatomic separation of the draining vein.

Effect of early debridement and open reduction combined with internal and external fixation on open fracture of tibia and fibula / 国际外科学杂志

Objective:To investigate the effect of early debridement and open reduction combined with internal and external fixation on open fracture of tibia and fibula.Methods:The clinical data of 82 patients with open tibiofibular fractures admitted to the 901st Hospital of the Joint Logistic Support Force of the Chinese People′s Liberation Army from June 2017 to May 2018 were retrospectively analyzed. There were 42 males and 40 females, aged 20-62 years, with an average age (34.8±16.1) years. According to different surgical methods, they were divided into control group ( n=32) and observation group ( n=50). The patients in the control group received early debridement and limited internal fixation, the patients in the observation group received early debridement and open reduction combined with internal and external fixation. The operation time, blood loss, healing time, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level, white blood cell count (WBC), excellent rate and complication rate were observed in both groups. The measurement data were expressed as mean±standard deviation( Mean± SD), comparison between groups was analyzed using independent sample t test, count data were expressed as percentage (%), comparison between groups was performed using chi-square test. Results:The operative time (98.35±15.14) min in the observation group were higher than those in the control group (79.26±13.22) min, blood loss (120.53±41.66) mL and healing time (16.84±5.07) min in the observation group were significantly lower than those in the control group [(79.26±13.22) min, (210.59±56.60) mL, (19.48±5.46) min]. The difference was statistically significant ( t values were 5.85, 7.76, 2.20, P<0.05). Compared with control group, the level of ESR (18.91±2.70) mm/h, CRP (39.20±3.13) ng/L, WBC (7.04±1.12)×10 3/L were significantly lower than control group [(27.36±3.28) mm/h, (45.63±4.06) ng/L, (11.06±1.51)×10 3/L]. The difference was statistically significant ( t values were 12.17, 7.63, 12.95, P<0.05). Compared with control groups′s excellent and good rate, the excellent and good rate of observation group was higher, but the difference was not statistically significant ( P>0.05). The incidence of complications in the observation group (6.00%, 3/50) was significantly lower than that in the control group (31.25%, 10/50) ( P<0.05). Conclusions:Early debridement and open reduction combined with internal and external fixation is an effective method for the treatment of open fracture of tibia and fibula. Compared with internal fixation, it has the advantages of shorter healing time, less blood loss and lower incidence of complications. And it can also reduce the inflammatory response of patients.

Enabling technologies in synthetic biology--DNA synthesis, assembly and editing / 生物工程学报

Synthetic biology is an emerging discipline, which aims at creating artificial lives or remolding the present organisms to generate new features. To achieve these goals, synthetic biologists need to design and synthesize new genes, pathways, modules or even whole genomes. As these enabling technologies (e.g. gene synthesis, DNA assembly and genome editing) are very important for the progress of synthetic biology, we will focus on the development of these technologies in this review.

Quality Evaluation and Index Exploration of the Glycyrrhetinic Acid Lipo-emul / 中国药房

OBJECTIVE:To provide reference indexs for the quality evaluation of Glycyrrhetinic acid lipo-emul. METHODS:Croy-TEM was used to detect the morphology of Glycyrrhetinic acid lipo-emul,laser nano-particle size analyzer was used to deter-mine the particle size,polydispersity index(PDI)and the zeta potential;UPLC was used to determine the drug loading of its ac-tive ingredient glycyrrhetinic acid;placing 10 d in 30 ℃,then stability was detected. RESULTS:Prepared Glycyrrhetinic acid li-po-emul was clear outline,structural integrity,roundlike and arranged closely;the mean particle size was(245.2±4.29)nm,PDI was (0.054 ± 0.01) and the mean zeta potential was (-6.25 ± 0.54) mV;the average drug loading of glycyrrhetinic acid was (1.25±0.09)mg/mL;the sample with mass concentration of 0.82 mg/mL showed good stability in within 10 d. CONCLUSIONS:Particle size,zeta potential,drug loading and stability can be used as the evaluation index of Glycyrrhetinic acid lipo-emul.

Study on the Effect of Hydrophilic/Hydrophobic Nano-silica with Different Adding Amount on the Stability of Glycyrrhetinic Acid Lipo-emulsion / 中国药房

OBJECTIVE:To study the effect of hydrophilic/hydrophobic nano-silica with different adding amount on the stabili-ty of lipo-emulsion. METHODS:Glycyrrhetinic acid lipo-emulsion 4 mL was taken,respectively adding into 0.5%,1.0%,1.5%(m/m,the same below) hydrophilic nSiO2,and 0.4%,0.75,1.0% hydrophobic nSiO2,incubating 2 h in 30 ℃ water;the same batch of Glycyrrhetinic acid lipo-emulsion was treated as blank control. The forms were observed under electron microscopy after treatment,absorbance value was determined,the stability parameter (KE) was calculated according to the absorbance value,then the adding amount of nSiO2 was optimized,3 batches of preparations was prepared,and the verification test was conducted. RE-SULTS:The spherical structure was Glycyrrhetinic acid lipo-emulsion in the electron microscopy,the substance wrapping its sur-face white ring (fully wrapped) or semi-circular structure (not fully wrapped) was nSiO2. KE of hydrophilic nSiO2 were 4.66%, 5.01% and -2.08%,and KE of hydrophobic nSiO2 were 3.02%,4.51% and 7.24%. The optimized adding amount of hydrophilic nSiO2 was 0.2%,0.3% and 0.4%,hydrophobic nSiO2 was 0.1%,0.2% and 0.3%;KE were 6.19%,3.05%,7.84%,8.42%, 2.41%,2.93%,respectively. The optimal adding amount was 0.3% hydrophilic nSiO2 and 0.2% hydrophobic nSiO2;the 3 batches of preparation showed the optimum stability in its own adding amount. CONCLUSIONS:Both hydrophilic and hydrophobic nSiO2 can improve the stability of Glycyrrhetinic acid lipo-emulsion,and preferably 0.3%,0.2%.

Quantitative study of meridian topology model based on acupoint-symptom relationship / 中国针灸

Meridian theory plays an important role in the guidance of clinical practice of acupuncture and moxibustion. Since the publication of(), the meridian theory has been developed. In the paper, in view of complex science, the topological properties of acupoint-symptom network were analyzed quantitatively by taking acupoint as node and indication as the connection, such as high clustering coefficient and the small world effect. It was the first time to give the abstraction for the topological proof of the high efficiency information transmission property of acupoint-symptom network meridian system at different times. Its quantitative and digitalized significance was analyzed on the development of meridian theory under the complex scientific background so as to provide a new thought and method for the study of meridian theory and acupuncture modernization.

Study on antibiotic resistance of Neisseria gonorrhoeae in Nanning for 5 years / 中华检验医学杂志

Objective To study the antibiotic resistance of Neisseria gonorrhoeae and the prevalence of penicillinase-producing Neisseria gonorrhoeae (PPNG) and high-level tetracycline resistant Neisseria gonorrhoeae (TRNG) in Nanning. Methods Minimum inhibitory concentrations (MIC) were determined by agar dilution method and ?-lactamase production was comfirmed by acidometric method.Results Among 458 strains, 33 strains(7.20%) were found to be PPNG and 231 strains(50.44%) were TRNG. The resistance rate to ciprofloxacin, ceftriaxone and spectinomycin were 87.33%, 1.31% and 0.22% respectively. Conclusion The situation of resistance to ciprofloxacin was very serious, and it was also found that a few of gonococcal isolates were resistant to ceftriaxone and spectinomycin. The study showed that it is important to successively survey the antibiotic resistance of Neisseria gonorrhoeae.