The effective coupling coefficient for a completed PIN-PMN-PT array.

The computation of the electromechanical coupling coefficient (EMCC) of a fully assembled medical ultrasound transducer array is directly computed with closed form expressions. The Levenberg-Marquardt non-linear regression algorithm (LMA) is employed to help confirm the EMCC calculated prediction (kEFF) and provide statistical insights. The complex electrical impedance spectra of a 1-3 composite array with two matching layers operating at a 3.75 MHz center frequency using PIN-PMN-PT single crystal material is measured in air both before and after oven heating at 160 °C for 15 min. The oven heating produces changes in the EMCC of -4.9%, clamped dielectric constant of -11%, and effective transducer longitudinal velocity of -2.5%. Utilizing the pre- and post-heating array impedance data, the calculated EMCC values from the new closed form expressions agree well with the complete KLM model based LMA, and also exhibit approximately one tenth the error as compared to the formulas for a flat, unloaded transducer.

[Robotic-assisted supraomohyoid neck dissection via retroauricular hairline incision].

Objective: To explore the feasibility of using da Vinci Surgical System to perform supraomohyoid neck dissection (SOND) to avoid visible scar and reduce trauma. Methods: Between September 2017 and December 2018, twenty patients (two females and 18 males, mean age, 54.8 years) with oral cancer treated in the Department of Stomatology, Hainan Hospital of General Hospital of Chinese PLA were enrolled in this study. Eight patients were assigned into robotic surgery group, and received robot-assisted SOND with retroauricular hairline incision. After the da Vinci Surgical System robotic platform was positioned, the neck dissection was performed in level Ⅱb, Ⅱa, Ⅲ, Ⅰb and Ⅰa orderly from the near region to far region. The other 12 patients were assigned into traditional surgery group, and received SOND with a traditional incision. The operation time, bleeding and amount of lymph node dissected were compared between two groups. Results: All the 8 cases of robot-assisted SOND were completed smoothly. Operation time [(4.5±1.0) h] was significantly longer in robotic surgery group than that [(2.5±1.0) h] in traditional surgery group (P<0.05). The amount of bleeding in robotic surgery group [30.0 (27.5) ml] was significantly lower than that in traditional surgery group [(100.0 (87.5) ml, P<0.05]. There's no difference in the number of lymph nodes dissected between robotic surgery group (23.6±5.2) and traditional surgery group (22.8±6.0)(P>0.05). No postoperative hemorrhage, symptoms of nerve injury, flap necrosis and secondary healing were observed in robotic surgery group. Conclusions: SOND through retroauricular hairline incision is feasible with the assistance of da Vinci Surgical System. The main advantage of this method is superior esthetic effects due to a hidden incision with minimal bleeding. There was no obvious differences in the amount of lymph nodes dissected and postoperative complications between two methods. However, robotic surgery costs a significantly longer operation time than traditional neck dissection.

[Trans-oral robotic submandibular gland removal].

Submandibular gland excision was performed on two patients using trans-oral robotic surgery (TORS). Complications such as the injury of marginal mandibular branch of facial nerve, ranula in the floor of the mouth, and postoperative hemorrhage were not observed. Visible cervical scar can be avoided and esthetic outcome can be expected by using this surgical modality.

[Influences of high-voltage electrical burns on microcirculation perfusion on serosal surface of small intestine of rats and the interventional effects of pentoxifylline].

Objective: To investigate influences of high-voltage electrical burns on microcirculation perfusion on serosal surface of small intestine of rats and the interventional effects of pentoxifylline (PTX). Methods: Totally 180 SD rats were divided into sham injury group, simple electrical burn group, and treatment group according to the random number table, with 60 rats in each group. The electrical current was applied to the outside proximal part of left forelimb of rats and exited from the outside proximal part of right hind limb of rats. Rats in simple electrical burn group and treatment group were inflicted with high-voltage electrical burn wounds of 1cm×1cm at current entrances and exits, with the voltage regulator and experimental transformer. Rats in sham injury group were sham injured through connecting the same equipments without electricity. At 2 min post injury, rats in sham injury group and simple electrical burn group were intraperitoneally injected with 2 mL normal saline, and rats in treatment group were injected with 2 mL PTX injection (50 mg/mL). At 15 min before injury and 5 min, 1 h, 2 h, 4 h, and 8 h post injury, 10 rats in each group were selected to collect blood of heart respectively. Serum were separated from the blood to determine the level of soluble vascular cell adhesion molecule-1(sVCAM-1) with enzyme-linked immunosorbent assay method. The number of adhesional leukocyte in mesenteric venule of rats was determined with Bradford variable projection microscope system. The microcirculation perfusion on serosal surface of small intestine of rats was detected with laser Doppler perfusion imager. Data were processed with analysis of variance of factorial design and LSD test. Results: (1) At 5 min, 1 h, 2 h, 4 h, 8 h post injury, the serum content of sVCAM-1 in rats of simple electrical burn group were (8 502±1 158), (11 793±3 310), (9 960±2 146), (9 708±1 429), (7 292±1 386) ng/mL respectively, higher than that in sham injury group and treatment group [ (1 897±946), (1 882±940), (1 882±938), (1 888±946), (1 884±942) ng/mL, and (6 840±1 558), (6 742±2 465), (5 625±2 593), (2 373±1 463), (5 187±2 797) ng/mL, respectively, with P values below 0.001]. The serum content of sVCAM-1 in rats of sham injury group and treatment group at all time points post injury, except 4 h post injury of treatment group, was higher than that of the same group at 15 min before injury (with P values below 0.001). (2) At all time points post injury, the number of adhesional leukocyte in mesenteric venule of rats in simple electrical burn group was higher than that in sham injury group and treatment group (with P values below 0.001). The number of adhesional leukocyte in mesenteric venule of rats in simple electrical burn group and treatment group at all time points post injury was higher than that of the same group at 15 min before injury (with P values below 0.001). (3) At all time points post injury, the microcirculation perfusion on serosal surface of small intestine of rats in simple electrical burn group was lower than that in sham injury group and treatment group (with P values below 0.001). The microcirculation perfusion on serosal surface of small intestine of rats in simple electrical burn group and treatment group at all time points post injury was lower than that of the same group at 15 min before injury (with P values below 0.001). Conclusions: High-voltage electrical burns can increase the serum content of sVCAM-1, the number of adhesional leukocyte in mesenteric venule, and reduce microcirculation perfusion on serosal surface of small intestine of rats. PTX can inhibit secretion of serum sVCAM-1, reduce the number of adhensional leukocyte in mesenteric venule to alleviate microcirculation disturbance caused by high-voltage electrical burns.

[Mendelian randomization analysis of the relationship between obesity and DNA methylation].

Objective: To explore the association between DNA methylation and body mass index (BMI) using Mendelian randomization analysis. Methods: A total of 469 participants were selected from the Chinese National Twin Registry in 2013, who were living in Shandong, Jiangsu, Zhejiang, and Sichuan provinces, and at least 18 years of age. A questionnaire survey and physical examination were conducted to collect demographic, clinical, and behavioral information. Peripheral blood cells were collected to detect genotype and methylation status. Association analyses between DNA methylation and BMI and between CpGs and cis-SNP were conducted. With rs748212 as the instrumental variable, the association between cg15053022 and BMI was explored using the Mendelian randomization method. Results: A total of 469 participants were selected. The mean age of participants was (44.8±13.2) years and the BMI was (25.0±3.8) kg/m(2). Nine BMI-related DNA methylation sites were found and DNA methylation site cg15053022 in the ATP4A gene was negatively associated with cis-SNP rs748212 (ß=-0.020); the mean methylation level of AA, AC, and CC were 0.212±0.025, 0.242±0.024, and 0.264±0.028, respectively. rs748212 was associated with BMI (ß=0.04, P=0.007) and closely related to cg15053022 (F=237.66, P=0.143). Mendelian randomization analysis showed lower methylation levels at cg15053022 were associated with higher BMI (ß=-1.97, P<0.001). Conclusion: This study supported the impact of cg15053022 methylation in the ATP4A gene on BMI using Mendelian randomization analysis and provided the basis for using Mendelian randomization analysis in methylation studies.

Cloning and heterologous expression of UDP-glycosyltransferase genes from Bacillus subtilis and its application in the glycosylation of ginsenoside Rh1.

UNLABELLED: Bacillus subtilis CCTCC AB 2012913 can transform ginsenoside Rh1 to 3-O-ß-D-glucopyranosyl-6-O-ß-D-glucopyranosyl-20(S)-protopanaxatriol. Based on its genome sequence, strain B. subtilis 168 contains three UDP-glycosyltransferase genes. Here, we cloned the three UDP-glycosyltransferase genes (ydhE1, yojK1 and yjiC1) from B. subtilis CCTCC AB 2012913 and expressed in Escherichia coli BL21 (DE3) with His-tag. The crude enzyme extracts were assayed, respectively, for their activities to transform ginsenoside Rh1. Extracts containing enzymes YojK1 and YjiC1 could use ginsenoside Rh1 as a substrate to produce 3-O-ß-D-glucopyranosyl-6-O-ß-D-glucopyranosyl-20(S)-protopanaxatriol, which had an additional glucopyranosyl linked with C-3 over the substrate. Enzyme YjiC1 was purified by affinity chromatography on Ni-NTA His Binding resin. The molecular mass of purified YjiC1 was c. 47 kDa as determined by SDS-PAGE. This is the first report of an in vitro biotransformation of ginsenoside Rh1 to 3-O-ß-D-glucopyranosyl-6-O-ß-D-glucopyranosyl-20(S)-protopanaxatriol using the recombinant UDP-glycosyltransferase. SIGNIFICANCE AND IMPACT OF THE STUDY: The Chinese traditional medicinal plant Panax is reported to have multiple health benefits. Its main active ingredient is saponin, and different saponins have different activity spectrum. In the study, three UDP-glycosyltransferase genes, ydhE1, yojK1 and yjiC1, were cloned from Bacillus subtilis CCTCC AB2012913 and the three genes were expressed in Escherichia coli BL21 (DE3). The enzyme YjiC1 was purified and converted ginsenoside Rh1 to 3-O-ß-D-glucopyranosyl-6-O-ß-D-glucopyranosyl-20(S)-protopanaxatriol in vitro. The compound is the first saponin possessing ß-glucopyranosyl at both C-3 and C-6 sites. We showed that the in vitro biotransformation was effective, and the reaction condition was easy to control. Our research suggests that a diversity of saponins could be generated through efficient and directed enzymatic biotransformation.

Styloid process osteochondroma.

Osteochondroma, a benign tumor of the skeleton and auxiliary tissues, is usually seen around the epiphysis of long bone, flat pelvis, scapula and transverse process of vertebra, but seldom in the head and neck region. The incidence of osteochondroma in the jaw bone only accounts for 0.6% of the whole body incidence, with rare reports of osteochondroma protruding into the oral cavity. Primary osteochondroma in the styloid process has not been reported until now. A case of styloid process osteochondroma and its surgical removal are here described.