Measurement of single particle impact charging under an external electric field

Electrostatic charges of granular materials always generate under a strong electric field for both nature and industry. To understand the impact charging of a single particle in such situations is therefore essential. However, the traditional Faraday cup approach has difficulty in determining the impact charge with the electric field. Here, we develop Millikan's method to measure the transferred charge of individual particle collision. The target plate lies beneath the vertical electrodes, and a high-speed camera records the particle movement. The single particle passes through the uniform electric field before and after colliding with the target. We can calculate the impact charge of the particle according to its initial charge and final charge, as well as the impact speed and impact angle. In addition, the electric field strength on the particle above the impact point is determined with the finite element method. The immunity to electric field influence on charge measurement and the ability to obtain relevant parameters make this a powerful tool to characterize charging processes under the electric field.

[Occupational characteristics and clinical manifestations of 245 cases of occupational brucellosis]

Objective: To analyse epidemiological, clinical characteristics and laboratory examination results of 245 occupational brucellosis form 2008 to 2018, which providing theoretical basis for prevention and control of occupational brucellosis. Methods: Based on the China Center for Disease Control and Prevention Information System, a database of occupational brucellosis cases in HunlunBuir from January 2008 to July 2018 was established. The Epidemiological characteristics, Clinical manifestation, laboratory examination of 245 occupational brucellosis and 359 without occupational brucellosis were comparatively analyzed about the same period. Results: Among the 245 patients, 219 were males, 254 in 359, malese were significantly higher than control group (χ(2)=21.331, P<0.05) . Fever, fatigue, hyperhidrosis and splenomegaly are common in patients with occupational brucellosis and non occupational brucellosis. Arthralgia (54.3%/44.8%) and CRP (81.2%/71.3%) were significantly also higher than control group (χ(2)=5.193, P<0.05; χ(2)=7.704, P<0.05) Fever, hyperhidrosis, fatigue and splenomegaly were common clinical manifestation and signs in the two groups. Brucellosis can cause a variety of complications, including osteoarticular hematological system and hepatic involvement, some patients with multiple system damage. Conclusion: The incidence of occupational brucellosis in HulunBuir is concentrated in agriculture and animal husbandry. Veterinarians are the main occupational groups, Occupational health interventions should be strengthened for key occupational hazards, regular occupational health examination, avoid chronic brucellosis and protect the health of key occupational groups.

[Application of low-dose ATG for GVHD prophylaxis in patients undergoing PBSCT aged over forty years old]

目的

探讨在供、受者年龄均≥40岁同胞相合外周血干细胞移植（MSD-PBSCT）移植物抗宿主病（GVHD）预防方案中增加低剂量抗胸腺细胞球蛋白（ATG）的效果。

方法

回顾性分析2013年3月至2017年4月行MSD-PBSCT且供、受者年龄均≥40岁恶性血液病患者的临床资料。43例患者在常规急性GVHD预防方案（环孢素A或他克莫司联合短疗程甲氨蝶呤）中加入ATG 1.5 mg·kg⁻¹·d⁻¹×3 d（ATG组），55例患者应用常规GVHD预防方案（对照组）。

结果

①ATG组中性粒细胞植入中位时间短于对照组[13（11~17）d对14（12~24）d，P=0.001]，血小板植入中位时间差异无统计学意义[14（11~43）d对15（11~42）d，P=0.071）]。②ATG组+100 d内急性GVHD累积发生率低于对照组[25.6%（95%CI 13.7%~39.3%）对49.1%（95%CI 35.2%~61.6%），P=0.018]，Ⅱ~Ⅳ度急性GVHD、慢性GVHD发生率差异无统计学意义[18.6%（95%CI 8.6%~31.5%）对23.6%（95%CI 13.4%~35.6%），P=0.509；49.6%（95%CI 31.6%~65.3%）对56.4%（95%CI 41.4%~69.0%），P=0.221]。③ATG组与对照组移植后1年巨细胞病毒血症累积发生率差异无统计学意义[21.1%（95%CI 10.3%~34.5%）对31.1%（95%CI 18.8%~44.2%），P=0.429]。④ATG组及对照组移植后2年累积复发率[24.0%（95%CI 11.5%~38.9%）对24.0%（95%CI 12.1%~38.2%），P=0.608]、非复发死亡率[10.2%（95%CI 3.1%~22.1%）对21.6%（95%CI 9.4%~37.0%），P=0.411]及无病生存率[65.8%（95%CI 50.3%~81.3%）对54.4%（95%CI 37.7%~71.1%），P=0.955]差异均无统计学意义，但ATG组移植后2年总生存率优于对照组[83.8%（95%CI 71.8%~90.0%）对58.0%（95%CI 42.2%~73.9%），P=0.019]。

结论

对于年龄较大的MSD-PBSCT患者，在常规GVHD预防方案基础上加入低剂量ATG可以显著降低移植后急性GVHD发生率、改善OS率，病毒感染发生率和复发率无明显增加。

[Accuracy analysis of computer assisted navigation for condylectomy via intraoral approach]

OBJECTIVE

To explore the application accuracy of virtual preoperative plan after the condylectomy via intraoral approach under computer assisted surgical navigation, and to analyze the location and cause of the surgical deviation to provide reference for the surgical procedure improvement in the future.

METHODS

In the study, 23 cases with condylar hypertrophy (11 with condylar osteochondroma and 12 with condylar benign hypertrophy) in Department of Oral and Maxilloficial Surgery, Peking University School and Hospital of Atomatology from December 2012 to December 2016 were treated by condylectomy via intraoral approach under computer assisted surgical navigation. The patient's spiral CT data were imported into ProPlan software before operation, and the affected mandibular ramus was reconstructed three-dimensionally. The condylar osteotomy line was designed according to the lesion range, and the preoperative design model was generated and introduced into the BrainLab navigation system. Under the guidance of computer navigation, the intraoral approach was used to complete the condylar resection according to the preoperative design of the osteotomy line. Cranial spiral CT of the craniofacial region was taken within one week after operation. three-dimensional reconstruction of the mandibular ramus at the condylectomy side was performed, and the condylar section was divided into six segments (anterolateral, anterior, anteromedial, posteromedial, posterior, and posterolateral) and the corresponding regional measurement points P1 to P6 were defined. Then the preoperative virtual model and the postoperative actual model were matched by Geomagic studio 12.0 to compare the differences and to analyze the accuracy of the operation.

RESULTS

All the patients had successfully accomplished the operation and obtained satisfactory results. Postoperative CT showed that the condyle lesion was completely resected, and the condylar osteotomy line was basically consistent with the surgical design. No tumor recurrence or temporomandibular joint ankylosis during the follow-up period. The postoperative accuracy analysis of the condylar resection showed that the confidence intervals measured by the six groups of P1 to P6 were (-2.26 mm, -1.89 mm), (-2.30 mm, -1.45 mm), (-3.37 mm, -2.91 mm), (-2.83 mm, -1.75 mm), (-1.13 mm, 0.99 mm), and(-1.17 mm, 0.17 mm), where P3 group was different from the other 5 groups. There was no significant difference between the P5 and P6 groups and the difference between the other four groups was statistically significant.

CONCLUSION

Under the guidance of computer navigation, the intraoral approach can be performed more accurately. The surgical deviation of each part of the osteotomy surface is mainly due to excessive resection. The anterior medial area of the anterior medial condyle represents the most excessive resection. The posterior and posterior lateral measurement points represent the posterior condylar area. The average deviation is not large, but the fluctuation of the deviation value is larger than that of the other four groups. The accuracy of computer-assisted subtotal resection has yet to be improved.

[Allogeneic hematopoietic stem cell transplantation for treatment of refractory and relapsed acute myeloid leukemia: outcomes and prognostic factors]

目的

评价异基因造血干细胞移植（allo-HSCT）治疗难治/复发急性髓系白血病（AML）的疗效，并对预后相关因素进行分析。

方法

回顾性分析allo-HSCT治疗99例难治/复发AML患者总体生存（OS）率、无病生存（DFS）率、移植物抗宿主病（GVHD）发生率、移植相关死亡率（TRM）及复发率，并分析影响预后的危险因素。

结果

全部99例患者中男59例，女40例，中位年龄为35（6~58）岁，均接受清髓性预处理。所有患者中性粒细胞均达植入标准，中位植活时间为14（9~25）d。移植后100 d Ⅱ~Ⅳ度急性GVHD累积发生率为27.3%（95% CI 18.9%~36.3%）；2年慢性GVHD累积发生率为33.9%（95%CI 24.6%~43.5%），其中广泛型慢性GVHD累积发生率为9.3%（95%CI 4.5%~16.1%）。移植后3年OS、DFS、TRM率分别为45.0%（95%CI 34.6%~55.4%）、45.0%（95%CI 34.8%~55.2%）、19.7%（95%CI 12.4%~28.3%），复发率为36.6%（95%CI 26.9%~46.4%）。多因素分析显示，影响OS的独立危险因素包括移植前未缓解[P=0.009，HR=2.21（95%CI 1.22~4.04）]、初诊WBC>50×10⁹/L[P=0.024，HR=2.11（95%CI 1.11~4.02）]、供者年龄>35岁[P=0.031，HR=1.96（95%CI 1.06~3.60）]、移植后未发生慢性GVHD[P=0.008，HR=0.38（95%CI 0.18~0.78）]。根据移植前危险因素（移植前未缓解、初诊WBC>50×10⁹/L、供者年龄>35岁）进行危险度分组，具有0、1、2~3个危险因素患者的3年OS率分别为75.0%、46.9%、15.4%（χ²=26.873，P<0.001）。

结论

allo-HSCT是挽救性治疗难治/复发AML的有效手段，复发是影响生存的主要原因。移植前缓解状态、发病时WBC水平、供者年龄及移植后是否发生慢性GVHD是难治/复发AML患者allo-HSCT预后的独立影响因素。

Responsive peptide-based supramolecular hydrogels constructed by self-immolative chemistry

Peptide-based supramolecular hydrogels that are stimuli-responsive under aqueous conditions have many potential biological applications, including drug delivery and sensing. Herein, we reported a series of responsive peptide-based supramolecular hydrogels that respond to glutathione (GSH), nitric oxide (NO) and hydrogen sulfide (H₂S), which are biologically important signaling molecules. The responsive hydrogelators were designed by "self-immolative" chemistry and constructed by using self-immolative groups to modify short peptides. The self-immolative capping group could be removed in the presence of a corresponding trigger, thus causing gel-sol phase transitions. The potential of our responsive hydrogels for drug release was also demonstrated in this study. Our study offered several candidates of responsive hydrogels for sensing and drug delivery.

Supramolecular Nanofibers of Drug-Peptide Amphiphile and Affibody Suppress HER2+ Tumor Growth

Antibody-based medicines and nanomedicines are very promising for cancer therapy due to the high specificity and efficacy of antibodies. However, antibody-drug conjugates and antibody-modified nanomaterials frequently suffer from low drug loading and loss of functions due to the covalent modification of the antibody. A novel and versatile strategy to prepare supramolecular nanomaterials by the coassembly of an affibody (antiHER2) and drug-peptide amphiphiles is reported here. During the enzyme-instructed self-assembly process, the drug-peptide amphiphile can coassemble with the affibody, resulting in supramolecular nanofibers in hydrogels. The drug loading in the supramolecular nanofibers is high (>30 wt%), and the stability of antiHER2 is significantly improved in the nanofibers at 37 °C (>15 d in vitro). The supramolecular nanofibers exhibit high affinity for HER2+ cancer cells and can be efficiently taken up by these cells. In a mouse tumor model, the supramolecular nanofibers abolish HER2+ NCI-N87 tumor growth due to the good accumulation and retention of nanofibers in tumor. This study provides a novel strategy to prepare nanomedicines with high drug loading and high specificity.

[Epidemiological, Occupational Characteristics and Clinical Manifestation of Occupational Forest Encephalitis in HunlunBuir city during 2008-2017]

Objective: To provide scientific evidence for Prevention and control measures of Occupational Forest Encephalitis (OFE) by analyzing the Epidemiological and occupational characteristics, clinical manifestation of OFE cases reported in HunlunBuir city during 2008~2017. Methods: Based on the China Center for Disease Control and Prevention Information System, a database of OFE cases in HunlunBuir from 2008~2017 was established. The Epidemiological characteristics of OFE were analyzed including three distributions, the available information includes 291 cases of population, geographical, periods, occupational distribution, clinical manifestations and laboratory examinations. Results: There were 291 OFE cases in HunlunBuir from 2008 to 2017, including 287 cases of mild OFE, Moderate, Serve in1, 3 cases, 282 male. In the temporal distribution, the most cases were 48 cases in 2011, 119 casesin June. 33.7% of the cases (98) were reported in Yakeshi, following 29.2% and 21.3% inroqen Autonomous Banner (85) , Genhe (62) . Of 291 cases, male were in 282.The high incidence of OFE mainly existed in Forest management 112 (38.5%) . The most clinical manifestation were headache in 195 (67%) , fever in 168 (57.7%) . Conclusion: The distribution of Occupational Forest Encephalitis cases in diverse regions and months in HunlunBuir are quite different. The occupational safety precautions of the forest workers and tick-borne encephalitis vaccines should be strengthened to reduce the occurrence of Occupational Forest Encephalitis.

Electro-acupuncture at ST37 and ST25 induce different effects on colonic motility via the enteric nervous system by affecting excitatory and inhibitory neurons

BACKGROUND

On the basis of the importance of the enteric nervous system (ENS) in gastrointestinal motility, we hypothesized that the ENS may mediate the therapeutic efficacy of electro-acupuncture (EA) in constipation by regulating the mechanisms underlying the effects of EA on gastrointestinal function.

METHODS

Model mice with constipation were generated by gastric instillation of 0-4°C normal saline. Defecation time and stool (form and wet and dry weight) were assessed. The effect of EA at ST37 or ST25 on colorectal motility and proximal colonic motility was assessed using a water-filled balloon. The expression of protein gene product 9.5 (PGP9.5), the cholinergic neuron marker acetyltransferase (ChAT) and the anticholinergic neuron marker nitric oxide synthase (nNOS) was detected by immunohistochemistry, real-time quantitative polymerase chain reaction (qPCR) and western blot analysis.

KEY RESULTS

ST37 and ST25 improved colorectal pressure; however, ST37 but not ST25 improved proximal colonic pressure. In the proximal colon, the expression of PGP9.5 returned to normal after EA at ST 37, while EA at ST25 did not have this effect. In addition, qPCR and western blot analysis showed that ST37 could downregulate the expression of nNOS and upregulate the expression of ChAT to normal levels, while ST25 could only downregulate the expression of nNOS to normal levels.

CONCLUSIONS AND INFERENCES

Electro-acupuncture at specific acupoints can improve intestinal motility in constipation by altering the ENS and differentially affecting excitatory and inhibitory neurons, restoring the coordination between contraction and relaxation muscles, and working in concert with the central nervous system and peripheral neural pathways.

[Study on the dynamic variations and influencing factors of serum lipid levels during pregnancy and postpartum]

Objective: To study the variations and influencing factors of serum triglycerides and cholesterol levels during pregnancy and postpartum. Methods: A retrospective study was performed among 5 020 healthy singleton (95.10%, 4 774/5 020) and twin (4.90%, 246/5 020) women who had delivery in Women's Hospital, Zhejiang University School of Medicine from January 2011 to December 2016. Serum triglycerides and cholesterol levels during pregnancy and postpartum of all the cases were collected. Both singleton and twin pregnant women were divided into advanced age and appropriate age groups, and then data of serum sample were assigned to 3 groups according to the gestation weeks, which were second trimester pregnancy (24-28 gestation weeks) , third trimester pregnancy (32-41 gestation weeks) and postpartum (within 72 hours after delivery) . The serum triglycerides and cholesterol levels in each groups were compared. Results: (1) Serum triglycerides and cholesterol levels during the second trimester pregnancy, third trimester pregnancy and postpartum were higher than levels of non-pregnancy in both singleton and twin groups (all P<0.05) . (2) Serum triglycerides and cholesterol levels in the third trimester pregnancy group were higher than those of second trimester pregnancy group in both advanced age and appropriate aged women regardless singleton or twin pregnancy (all P<0.05) . The 95%CI of serum lipid levels in each group during second and third trimester pregnancy were as follows: in appropriate aged singleton group, the triglycerides levels were 1.07-4.13 and 1.52-7.21 mmol/L, and the cholesterol levels were 2.77-12.11 and 4.44-9.36 mmol/L. In advanced aged singleton group, the triglycerides levels were 1.28-4.61 and 1.70-7.80 mmol/L, and the cholesterol levels were 4.35-8.40 and 4.46-9.35 mmol/L; in appropriate aged twin group, the triglycerides levels were 1.39-7.16 and 1.90-9.29 mmol/L, and the cholesterol levels were 4.99-12.16 and 4.52-10.07 mmol/L; in advanced aged twin group, the triglycerides levels were 1.61-5.32 and 1.94-9.29 mmol/L, and the cholesterol levels were 5.24-8.10 and 4.53-8.86 mmol/L. (3) Serum lipids levels rapidly decreased during postpartum compared to the third trimester pregnancy. The 95%CI of blood lipid levels in each group were as follows: in appropriate aged singleton group, the triglycerides level was 0.90-5.64 mmol/L and the cholesterol level was 4.70-8.52 mmol/L; in advanced aged singleton group, the triglycerides level was 0.87-5.43 mmol/L and the cholesterol level was 4.68-9.04 mmol/L; in appropriate aged twin group, the triglycerides level was 1.20-8.21 mmol/L and the cholesterol level was 4.66-8.45 mmol/L; in advanced aged twin group, the triglycerides level was 1.32-6.61 mmol/L, and the cholesterol level was 5.01-7.94 mmol/L. (4) Serum triglycerides and cholesterol levels in twin pregnant women were significantly higher than in singleton during the second trimester and third trimester pregnancy both in advanced age and appropriate age groups (all P<0.05) . During postpartum, there was no difference in serum lipid levels between the singleton and twin pregnant women in appropriate age group (triglycerides: P=0.982; cholesterol: P=0.759, respectively) . While the serum lipid levels in twin pregnant women were significantly higher than those of singleton women in advanced age group (triglycerides: P=0.000; cholesterol: P=0.000, respectively) . Conclusions: The standard of serum lipid levels of non-pregnant adults is not suitable for assessing that in pregnant women. Regardless of singleton or twin pregnancy, serum triglyceride and cholesterol levels during pregnancy elevate with the increasing gestational week and then rapidly decrease during postpartum. Age and twins are the influencing factors of the elevated physiological lipid levels during pregnancy.

Parent Artery Reconstruction for Large or Giant Cerebral Aneurysms Using the Tubridge Flow Diverter: A Multicenter, Randomized, Controlled Clinical Trial (PARAT)

BACKGROUND AND PURPOSE

Although flow diverters have been reported with favorable clinical and angiographic outcomes in various literatures, randomized trials determining their true effectiveness and safety are still in lack. The Parent Artery Reconstruction for Large or Giant Cerebral Aneurysms Using the Tubridge Flow Diverter (PARAT) trial was designed to evaluate the safety and efficacy of the Tubridge flow diverter in the treatment of large or giant aneurysms in comparison with Enterprise stent-assisted coiling.

MATERIALS AND METHODS

This prospective, multicenter, randomized trial was conducted at 12 hospitals throughout China. Enrolled adults with unruptured large/giant intracranial aneurysms were randomly assigned (1:1) to receive either Enterprise stent-assisted coiling or Tubridge flow diverter implantation. The primary end point was complete occlusion at 6-month follow-up, while secondary end points included technical success, mortality, target vessel-related stroke, aneurysm bleeding, in-stent stenosis, parent artery occlusion, and the frequency of all adverse events.

RESULTS

Among 185 enrolled subjects, 41 withdrew before procedure initiation. Overall, 82 subjects underwent Tubridge implantation, and 62 subjects were primarily treated with stent-assisted coiling. The results of 6-month follow-up imaging included complete occlusion rates of 75.34% versus 24.53% for the Tubridge and stent-assisted coiling groups, respectively, with a calculated common odds ratio of 9.4 (95% confidence interval, 4.14-21.38; P < .001). There was a higher, nonsignificant frequency of complications for Tubridge subjects. Multivariate analysis showed a decreased stroke rate at the primary investigational site, with a marginal P value (P = .051).

CONCLUSIONS

This trial showed an obviously higher rate of large and giant aneurysm obliteration with the Tubridge FD over Enterprise stent-assisted coiling. However, this higher obliteration rate came at the cost of a nonsignificantly higher rate of complications. Investigational site comparisons suggested that a learning curve for flow-diverter implantation should be recognized and factored into trial designs.