[Evaluation of ankle joint protection effect of parachute ankle brace on paratrooper landing].

Objective: To study the protective effect of parachute ankle brace on ankle joint during simulated parachuting landing. Methods: In August 2021, 30 male paratroopers were selected as the test subjects by simple random sampling method. They jumped from the 1.5 m and 2.0 m height platforms respectively with and without parachute ankle brace, and landed on the sandy ground in a semi-squat parachute landing position. The experiment was divided into 1.5 m experimental group and control group and 2.0 m experimental group and control group. Angle sensor and surface electromyograph were used to measure and analyze the coronal tilt range of the ankle joint and the percentage of maximal voluntary contraction (MVE%) of the muscles around the ankle joint, respectively, to evaluate the protective effect of the parachute ankle brace. Results: At the same height, the tilt range of coronal plane of ankle in experimental group was significantly reduced compared with control group, and the difference was statistically significant (P<0.05). Under the same protection state, the tilt range of the coronal plane of the ankle in the 1.5 m group was significantly reduced compared with that in the 2.0 m group, and the difference was statistically significant (P<0.05). The coronal plane inclination range of the ankle in 2 m experimental group was significantly lower than that in 1.5 m control group, and the difference was statistically significant (P<0.05). Compared with 1.5 m control group, MVE% of right tibialis anterior muscle and bilateral lateral gastrocnemius decreased in 1.5 m experimental group, while MVE% of bilateral peroneus longus increased, with statistical significance (P<0.05). Compared with 2.0 m control group, the MVE% of bilateral tibialis anterior muscle and right lateral gastrocnemius decreased in 2.0 m experimental group, while the MVE% of bilateral peroneus longus increased, with statistical significance (P<0.05). The MVE% of bilateral tibialis anterior muscle, bilateral lateral gastrocnemius muscle and right peroneus longus muscle in 1.5 m experimental group decreased compared with 2.0 m experimental group, and the differences were statistically significant (P<0.05). Compared with 2.0 m control group, the MVE% of bilateral tibialis anterior muscle, right lateral gastrocnemius muscle and right peroneus longus muscle in 1.5 m control group decreased, and the differences were statistically significant (P<0.05) . Conclusion: Wearing parachute ankle brace can effectively limit the coronal plane inclination range of ankle joint, improve the stability of ankle joint and reduce the load on the muscles around ankle joint by landing. Reducing the height of the jumping platform can reduce the coronal plane incline range of the ankle and the muscle load around the ankle during landing.

Lung protection effect of EIT-based individualized protective ventilation strategy in patients with partial pulmonary resection.

OBJECTIVE: This study aimed to evaluate the lung protection effect of an individualized protective ventilation strategy based on lung impedance tomography (EIT) technology in patients with partial pulmonary resection. PATIENTS AND METHODS: Eighty patients of any gender, American Society of Anesthesiologists (ASA) classification I-II, age 30-64 years and body mass index (BMI) 18-28 kg/m2 who underwent elective thoracoscopic partial lung resection were selected and divided into 2 groups (n=40) using the random number table method: [positive end-expiratory pressure (PEEP) by electrical impedance tomography (EIT)] PEEPEIT group (experimental group) and control group. The PEEPEIT group used volume-controlled ventilation after one-lung ventilation, setting a tidal volume of 6 ml/kg and titrating the optimal PEEP value by EIT. Group C used volume-controlled ventilation after one-lung ventilation, setting a tidal volume of 6 ml/kg and a PEEP of 5 cm H2O. Clinical data were collected and recorded at 5 min after double lung ventilation (T0), single lung ventilation, 30 min after PEEP setting (T1), 60 min after PEEP setting (T2), the end of surgery, 10 min after resumption of double lung ventilation (T3) and 10 min after removal of the tracheal tube (T4), and serum surface active substance-associated protein-A (SP-A) concentrations were measured at T0, T3 and 1 d after surgery (T5). RESULTS: PEEP values were higher in the PEEPEIT group than in the control group at T1 and T2 (p-value <0.05); oxygenation index (OI) was higher in the PEEPEIT group compared to the control group at T2 and T3 (p-value <0.05); pulmonary dynamic compliance (Cdyn) was higher in the PEEPEIT group compared to the control group at T1 and T2 (p-value <0.05); intrapulmonary shunt rate (Qs/Qt) was lower in the PEEPEIT group compared to the control group at T1, T2 and at T3, the intrapulmonary shunt rate (Qs/Qt) was reduced in the PEEPEIT group compared to group C (p-value <0.05); at T5, the SP-A protein was reduced in the PEEPEIT group compared to group C. There was no statistically significant difference in the incidence of postoperative pulmonary complications between the two groups (p-value >0.05). CONCLUSIONS: The EIT-guided individualized protective ventilation strategy has a lung-protective effect in patients undergoing thoracoscopic partial lung resection.

[Clinical and pathological characteristics of gastric adenocarcinoma of fundic gland type].

To analyze the clinical, endoscopic and pathological feature of gastric adenocarcinoma of fundic gland type (GA-FG) (18 cases) collected from Sir Run Run Shaw Hospital, affiliated with Zhejiang University School of Medicine and Taizhou Hospital of Zhejiang Province from January 2019 to July 2022. There were 18 cases of patient of GA-FG, including male 12 cases, female 6 cases, aged from 38 to 78 years old, with average age of 60.5 years old. Gastroscopy showed that bulging or flat lesions of gastric fundus were 0.2-5.5 cm in size, and the mucosal surface was smooth, redness or rough. Histologic examination showed that tumor cells were dominated by chief cells and scattered with a few oxyntic cells, formed a complex gland that anastomoses each other, and infiltrated to the submucosa. The results of immunohistochemistry showed that tumor cells were positive for the expression of mucin-6 (MUC6) and Pepsinogen 1, and partial expression of synaptophysin (Syn). GA-FG is a rare type of gastric adenocarcinoma with good differentiation, and currently only a few cases have been reported, and often easily been misdiagnosed or missed. Therefore, to master the characteristics of clinic and pathology is helpful to improve the ability of clinical pathologists in differential diagnosis.

[Study on surface electromyography characteristics of erector spinae muscles at different spinal anteversion angles of the scrapers].

Objective: To simulate and evaluate the scraping and grinding work of workers with different spinal anteversion angles, and to explore the effects of different anteversion angles on the erector spinae muscles of scrapers. Methods: In November 2019, 16 male college student volunteers were recruited to simulate workers' scraping and grinding work. The parameters were 25°, 15 times/min, 15°, 30 times/min, 5°, 60 times/min respectively. The surface electromyography (sEMG) was used to collect the electromyographic signals of the erector spinae muscles, and the surface electromyographic characteristics of the erector spinae muscles were evaluated with Borg Scale. Results: There were significant differences between the maximum voluntary contraction percentage (MVE%) of the left and right erector spinae muscles groups in the three groups with different spinal anteversion angles (F(left)=13.41, P(left)<0.001; F(right)=4.74, P(right)=0.005) , and the EMG amplitude was higher at 25°, 15 times/min. At 15°, 30 times/min, MVE% of the left side was significantly higher than that of the right side (t=2.58, P=0.021) . There was significant difference in the mean power frequency (MPF) of the right erector spinae muscle in the three groups (F=9.42, P<0.001) , but there was no significant difference in the MPF of the left erector spinae muscle (F=0.30, P=0.823) . The fitting line showed that the left erector spinae muscle showed a downward trend at 5°, 60 times/min (t=-5.39, P=0.012) . Conclusion: Scrapers are less likely to be fatigued when the posture is 15°, 30 times/min, but they are more likely to be fatigued when working at 5°, 60 times/min.

[Safety and efficacy of intra-arterial tirofiban infusion in patients with acute cardiogenic cerebral embolism undergoing endovascular reperfusion therapy].

Objective: To evaluate the safety and efficacy of intra-arterial tirofiban infusion during endovascular reperfusion therapy in patients with acute cardiogenic cerebral embolism. Methods: Clinical data of 72 patients with acute cardiogenic cerebral embolism caused by large artery occlusion were retrospectively analyzed in Department of Neurology, Strategic Support Force Medical Center from August 2015 to August 2020.Among those, 52 patients were treated with intra-arterial tirofiban, the other 20 patients were treated with control medication. The baseline characteristics, modified thrombolysis in cerebral infarction (mTICI) score of responsible vessels, modified Rankin scale (mRS) score 90 days after operation, incidence of symptomatic intracranial hemorrhage and mortality were evaluated and compared in two groups. Results: The proportion of effective recanalization of the offending vessels (mTICI≥2b) in tirofiban group was higher than that in control group (92.3% vs. 75.0%), but the difference was not statistically significant (P=0.104). At 90 days after operation, the rate of patients with good prognosis (mRS≤2) in tirofiban group (61.5%) was significantly higher than that in control group (35.0%) (P<0.05). The incidence of symptomatic intracranial hemorrhage and mortality were comparable between the two groups (P>0.05). Conclusion: Intra-arterial tirofiban infusion in patients with acute cardiogenic cerebral embolism is effective and feasible, which improves the prognosis without increasing the risk of intracranial bleeding complications.

[Application of single-cell transcriptome sequencing in mechanistic toxicology].

Traditional bulk RNA sequencing assesses the average expression level of genes in tissues rather than the differences in cellular responses. Accordingly, it is hard to differentiate sensitive responding cells, leading to inaccurate identification of toxicity pathways. Single-cell RNA sequencing (scRNA-seq) isolated single cells from tissue and subjected them to cell subtypes-specific transcriptome analysis. This technique in toxicological studies realizes the heterogeneous cellular responses in the tissue microenvironment upon chemical exposure. Thus it helps to identify sensitive responding cells and key molecular events, providing a powerful tool and a new perspective for exploring the mechanisms of toxicity and the modes of action. This review summarizes the development, principle, method, application and limitations of scRNA-seq in mechanistic toxicological researches, and discusses the prospect of multi-directional applications.

[Molecular mechanism of zoledronic acid inhibiting angiogenesis by semi flexible binding with vascular endothelial growth factor conformation].

Objective: To study the relationship between zoledronic acid (ZOL) and vascular endothelial growth factor (VEGF) conformation so as to reveal the mechanism of bisphosphonates inhibiting angiogenesis. Methods: The binding structures of ZOL and VEGF were preprocessed and the molecular dockings were simulated through AutoDockTools, Discovery studio4 and AutoDockVina. The best binding conformation was accurately screened. The effects of various concentrations of ZOL (group A was 0 µmol/L, groups B, C and D were 25, 50 and 100 µmol/L, respectively) on human umbilical vein endothelial cell (HUVEC) proliferation, angiogenesis and angiogenic molecules were detected by using cell counting kit-8 (CCK-8) in vivo and in vitro angiogenesis, immunofluorescence and Western blotting. Results: There was a ZOL binding site on the target protein VEGF conformation. The affinity was -5.2 kcal/mol. This binding site consisted of the hydrophobic region composed of amino acids Cys26, 51, 57, etc. and the hydrogen bond binding region of the A chain (ASP34, SER50) and B chain (CYS61, 68, LEU66, GLY59). The results of CCK-8 showed that the levels of value A in groups B, C and D were significantly lower than that in group A at each time point from 3 to 6 days (P<0.05). In vitro vascular experiments demonstrated that the numbers of budding in groups B, C and D [(208±28), (151±21) and (62±9), respectively] were significantly lower than that in group A (276±30) (P<0.05). In vivo vascular experiments displayed that the ratio of Matrigel gel/plasma fluorescence in group A (0.003 1±0.000 3) was significantly higher than those in group B (0.002 1±0.000 2), group C (0.001 6±0.000 2) and group D (0.000 6±0.000 1) (P<0.05). The results of Western blotting revealed that the expression of VEGF in groups B, C and D [(0.72±0.11), (0.41±0.07) and (0.24±0.04), respectively] were significantly lower than that in group A (1.01±0.02) (P<0.05), and the expression levels of hypoxia-inducible factor-1α (HIF-1α) in groups B, C and D [(0.68±0.09), (0.55±0.06) and (0.43±0.08), respectively] were significantly lower than that in group A (0.96±0.04) (P<0.05). Conclusions: ZOL could inhibit cell proliferation, in vivo and in vitro vascularization and expression of VEGF/HIF-1α. The binding site of ZOL with the conformation of VEGF was located in the hydrophobic region and hydrogen-bonding region of amino acids. Designing an antagonist targeting this site might potentially alleviate the effect of ZOL in inhibiting angiogenesis.

Giant isotropic magneto-thermal conductivity of metallic spin liquid candidate Pr2Ir2O7 with quantum criticality.

Spin liquids are exotic states with no spontaneous symmetry breaking down to zero-temperature because of the highly entangled and fluctuating spins in frustrated systems. Exotic excitations like magnetic monopoles, visons, and photons may emerge from quantum spin ice states, a special kind of spin liquids in pyrochlore lattices. These materials usually are insulators, with an exception of the pyrochlore iridate Pr2Ir2O7, which was proposed as a metallic spin liquid located at a zero-field quantum critical point. Here we report the ultralow-temperature thermal conductivity measurements on Pr2Ir2O7. The Wiedemann-Franz law is verified at high fields and inferred at zero field, suggesting no breakdown of Landau quasiparticles at the quantum critical point, and the absence of mobile fermionic excitations. This result puts strong constraints on the description of the quantum criticality in Pr2Ir2O7. Unexpectedly, although the specific heats are anisotropic with respect to magnetic field directions, the thermal conductivities display the giant but isotropic response. This indicates that quadrupolar interactions and quantum fluctuations are important, which will help determine the true ground state of this material.

[Current status and research progress in load assessment methods for occupational low back pain].

With the development of industry, musculoskeletal disorders have become increasingly prominent, and low back pain is one of the major problems. The United States and Germany have already included it in the category of occupational diseases. Therefore, it is extremely important to determine the occupational factors affecting low back pain and evaluate the load level of workers. In this paper, combined with the existing literature, the evaluation methods of the load of low back pain were reviewed, in order to provide reference for the development of prevention strategies of low back pain from the perspective of occupational factors.

[Effect of metformin on mitochondrial pathway of apoptosis and oxidative stress in cell model of nonalcoholic fatty liver disease].

Objective: To investigate the effects of metformin on mitochondrial pathway of apoptosis and oxidative stress in cell model of nonalcoholic fatty liver disease. Methods: An in vitro cell model of nonalcoholic fatty liver disease was established using 0.6 mmol/L oleic acid to induce lipid accumulation in HepG2 cells. HepG2 cells were divided into control (Con) group, oleic acid (OA) group, and metformin-low (1mmol/L) and high (10mmol/L) dose group. Oil Red O stain was used to detect intracellular lipid droplet distribution. The levels of alanine aminotransferase and aspartate aminotransferase in the culture supernatant were detected by assay kits. DCFH-DA method was used to detect the reactive oxygen species of HepG2 cells. Double staining flow cytometry was used to detect the apoptosis rate of HepG2 cells. Western blot was used to detect caspase-3, B-lymphocyte lymphoma-related protein, B-cell lymphoma 2, and cytochrome c protein. One-way analysis of variance was used to compare the data between groups. Results: Oleic acid-induced HepG2 cells were significantly increased with lipid droplets. Low and high-dose metformin had reduced intracellular lipid droplets accumulation. The effect of metformin in the high-dose group was more significant than that in the low-dose group. Aspartate aminotransferase and alanine aminotransferase in HepG2 cells of OA group were significantly increased, which were (43.41 ± 7.11) U/L and (29.56 ± 4.11) U/L, respectively. The intracellular aspartate aminotransferase and alanine aminotransferase were decreased significantly after the treatment with low and high-dose metformin, which were (32.44 ± 4.08)U/L, (19.31 ± 3.03) U/L, (26.00 ± 3.11) U/L and (15.11 ± 4.11) U/L, respectively and the differences were statistically significant (P < 0.05). DCFH-DA test results showed that the fluorescence intensity of reactive oxygen species in the oleic acid group was 41.21% ± 4.23%, while the fluorescence intensity of reactive oxygen species in the low and high-dose metformin groups were reduced to 27.44% ± 3.91%, and 17.55% ± 5.11%, respectively and the differences between the groups were statistically significant (P < 0.05). The results of flow cytometry analysis showed that the cell apoptosis rate of the OA group was significantly higher than that of the Con group (12.12% ± 0.72% vs. 3.04% ± 0.57%, P < 0.05).The apoptosis rate of HepG2 cells was significantly reduced after metformin treatment at low and high doses (8.71% ± 0.71%, 5.71% ± 0.61%, P < 0.05). Western blot results showed that compared with the Con group, the expressions of B-lymphocyte lymphoma-related protein, cytochrome c, and caspase-3 were increased in the OA group, while the B-cell lymphoma 2 were decreased (P < 0.05). The expression of B-lymphocyte lymphoma-related protein, cytochrome c, and caspase-3 protein in HepG2 cells was decreased after treatment with low and high-dose metformin, while B-cell lymphoma 2 was increased (P < 0.05). Conclusion: Metformin can effectively alleviate steatosis and improve the HepG2 function in cell model of nonalcoholic fatty liver disease. The mechanism of metformin may be related to the reduction of oxidative stress injury, the regulation of protein expression related to mitochondrial apoptosis pathway and the inhibition of cell apoptosis.

MicroRNA-506-3p inhibits proliferation and promotes apoptosis in ovarian cancer cell via targeting SIRT1/AKT/FOXO3a signaling pathway.

Ovarian cancer (OC) is one of the most common tumors in females. Growing evidence shows that microRNA-506-3p (miR-506-3p) is downregulated in OC tissues. The purpose of this study was to investigate the mechanism of miR-506-3p in modulating OC. Quantitative reverse transcriptase PCR (qRT-PCR) was employed to investigate the expression of miR-506-3p and its target in OC tissues or cell lines. CCK-8 or colony formation assay was used to examine cell viability or proliferation, respectively. Flow cytometry was demonstrated to detect cell apoptosis. Western blot was then applied to analyze underlying mechanisms. The potential target of miR-506-3p was examined via luciferase reporter assay. MiR-506-3p was significantly downregulated in both human OC tissues and cell lines. Overexpression of miR-506-3p not only decreased cell viability of OC cell lines but also promoted cell apoptosis, thus inhibiting OC progression. Moreover, SIRT1 (Sirtuin 1) was found to be a direct target of miR-506-3p, and SIRT1 expression was negatively regulated by miR-506-3p in OC cell lines. Further investigation revealed that overexpression of SIRT1 could promote cell viability as well as inhibit cell apoptosis, showing the reversed effect on OC progression compared to miR-506-3p. Lastly, AKT (Protein kinase B) /FOXO3a (Forkhead box O3) signaling pathway was inactivated by miR-506-3p while activated by SIRT1, relating to regulation of miR-506-3p on OC progression. Our results revealed a novel mechanism by which miR-506-3p inhibited proliferation while promoted apoptosis of OC via inactivation of SIRT1/AKT/FOXO3a signaling pathway, suggesting that miR-506-3p might be a potential target for OC.

[A multi-center clinical retrospective study on the therapeutic effect of endoscopic myringoplasty].

Objective: To analyze the therapeutic effect of endoscopic myringoplasty. Methods: A retrospective analysis of 523 patients with chronic otitis media who underwent endoscopic myringoplasty between June 2016 and June 2017 in eight tertiary hospitals in China. Among all the patients, 256 were male and 267 were female, aged from 18 to 68 years old. The grafts used to repair the tympanic membrane were all tragus cartilage-perichondrium complex. All patients were followed up at 1 month, 3 months, 6 months, 9 months, and 12 months after surgery, at least 3 months. The closure rate of tympanic membrane perforation by different factors, the hearing results, and the incidence of postoperative complications were analyzed. SPSS 21.0 software was used to analyze the data. Results: Three months after operation, the closure rates of anterior, inferior, posterior and subtotal perforation were 92.4% (109/118), 94.9% (93/98), 95.6% (129/135), and 89.0% (153/172) respectively, the difference was not statistically significant (χ(2)=5.779, P=0.123). The closure rates of small, medium and large perforations were 100.0% (82/82), 93.7% (178/190) and 89.2% (224/251) respectively. The difference was statistically significant (χ(2)=10.927, P=0.004). The closure rates of dry ear and wet ear tympanic membrane perforation were 93.1% (392/421), 90.2% (92/102), the difference was not statistically significant (χ(2)=1.011, P=0.915). The preoperative pure tone audiometry(PTA) was (38.4±5.3) dBHL, while, the 3-month postoperative PTA was (25.1±5.7) dBHL. The difference was statistically significant (t=39.079, P<0.001). The preoperative air bone gap (ABG) was (22.4±4.3) dB, while 3 months postoperative ABG was (9.1±3.8) dB. The difference was statistically significant (t=53.004, P<0.001). Of all 523 patients, 14 (2.7%) had middle ear infection, 8 (1.5%) had dislocated tympanic membrane, 12 (2.3%) had parageusia, 35 (6.7%) had tinnitus, 28 (5.4%) had hearing loss, 26 (5.0%) had vertigo,33 (6.3%) had reperforation, 2 (0.4%) had secondary cholesteatoma, and none had facioplegia. Conclusions: Endoscopic myringoplasty is a safe and effective surgical method with good postoperative outcome.

[Management of 242 patients with middle ear cholesteatoma by otoendoscopic surgery and the postoperative effect analysis].

Objective: To summarize and discuss the characteristics of endoscopic approach to manage the middle ear cholesteatoma, and to evaluate the operative safety and outcomes based on the data from the multicenter study. Methods: The data of 242 cases diagnosed with the middle ear cholesteatoma and received operation through endoscopic approach between June 2016 and June 2017 in six tertiary hospitals in China were analyzed in this work. There were 130 males and 112 females, with the age ranging from 3 to 72 years old. We evaluated the strategy about how to manage the cholesteatoma, discussed the detailed techniques about how to remove the cholesteatoma and to improve the efficiency under endoscopic visualization. Meanwhile, the recurrence rate and residual rate of cholesteatoma as well as the complications in endoscopic approach were summarized. Results: A total of 158 cases were operated in exclusively endoscopic transcanal approach, 72 cases operated in combined approach, and 12 cases operated majorly under microscope and minorly under endoscope. 219 cases were operated in one stage surgery, 23 cases received second look. In the second look, 3 cases were detected with residual cholesteatomas. Among them, 2 cases were found by MRI-DWI examination after the first-stage operation. With endoscopic examination after operation, 17 cases showed retracted pocket recurrence (7%,17/242). With introduction of endoscope in cholesteatoma, 153 cases were achieved canal wall-up operation (63%, 153/242). The complications in endoscopic approach included chord tympani never injury in 27 cases, skin injury of ear canal in 11 cases, tinnitus in 13 cases, vertigo in 7 cases, external ear canal stenosis in 1 case. Conclusions: Using otoendoscope in cholesteatoma surgery would help keeping the normal structures of middle ear as much as possible, benefit to remove the hiding pathologies, help reducing residual cholesteatoma and lowering the rate of canal wall-down operation as well. This study showed good safety of otoendoscopic cholesteatoma surgery, however, strict evaluation of indication and quite good surgical techniques and skills are necessary for avoiding unexpected complication.

[Evaluation of the safety and effect of the endoscopic stapes surgery: a multi-center study].

Objective: To analyze the safety of endoscopic stapes surgery, and to compare the results with stapes surgery under microscopic approach. Methods: This was a retrospective study. One hundred and thirty seven patients from Eye Ear Nose and Throat Hospital of Fudan University and other seven hospitals were enrolled in this study. Eighty eight patients, in whom 29 were male, and 59 were female, aged from 29 to 66 years old, with an average of 40.1±10.7, underwent endoscopic stapedotomy and 49 patients, in whom 17 were male, and 33 were female, aged from 32 to 64 yeas old, with an arerage of 38.7±9.2, underwent microscopic stapedotomy for otosclerosis. Interventions included endoscopic and microscopic stapes surgeries. Main outcome measures consisted of operating time, preoperative and postoperative hearing, intraoperative findings, and postoperative complications. SPSS 16.0 software was used to analyzed the date (t test and χ(2) test) . Results: Patients in the group who underwent endoscopic stapes surgery showed a mean operative time of (74.1±26.0) min. Patients in the group treated by microscopic approach had a mean operative time (66.5±15.9) min. Statistical difference was evident (t=1.279, P<0.05) . The average operative time of endoscopic surgery became shorter as the cases increased. The average duration of the last 10 cases was shorter than that of the first 10 cases in both groups. The differences were significant (t value was 3.028, 3.610, both P<0.05). No statistical difference was found in air conduction threshold improvement (t=1.074, P=0.289) , air-bone gap closure (t=-0.135, P=0.893) and bone conduction improvement (t=1.222, P=0.228) between the two groups. No difference regarding the incidence of the postoperative complications (chorda tympanum damage: 6 cases vs 2 cases, χ(2)=0.08,P>0.05; vertigo:18 cases vs 9 cases,χ(2)=0.09, P>0.05; facial paralysis: 0 case vs 0 case) between the two groups was found. Conclusion: Audiological outcomes achieved by endoscopic surgery are similar to the results obtained through a microscopic approach. Endoscopic stapes surgery is safe.

[Progress in middle ear dysventilation research].

Disfunction of Eustachian tube will cause negative pressure of middle ear, which may result in tympanic membrane retraction pocket. Severe pocket can consequently cause cholesteatoma. In clinical practice it is not uncommon to find a cholesteatoma limited to epitympanum, with an otherwise normal pars tensa and mesotympanum. This review explains the theory of "selective epitympanic dysventilation syndrome" developed by endoscopic technique. In the majority of the patients, the only ventilation pathway to the epitympanum is through the tympanic isthmus. Even if Eustachian tube function has recovered, an isthmus blockage with selective epitympanic dysventilation may lead to common attic cholesteatoma.

[Temporal bone anatomy via transcanal endoscopy].

Based on anatomy and clinical operation, this article discussed the anatomical structure of temporal bone and its contiguous relationship under oto-endoscope, through two approaches: the natural external auditory canal and the enlarged external auditory canal. To give an account of the anatomical characteristics of temporal bone under oto-endoscope.

[Children's non-carcinogenic health risk assessment of heavy metals exposure to residential indoor dust around an e-waste dismantling area in South China].

Objective: To evaluate the non-carcinogenic health risk of heavy metals (As, Cd, Cr, Cu, Mn, Pb and Zn) in residential indoor dust for young children around an e-waste dismantling area in South China. Methods: A village around an e-waste dismantling area in South China was selected as a research site in October 2016. Convenience sampling method was used to select 36 houses in the village and 36 dust samples were collected by vacuum cleaner. The concentrations of heavy metals (Cd, Cr, Cu, Mn, Pb and Zn) in each sample were determined and expressed by the average value. Non-carcinogenic health risk assessment was conducted using the US Environmental Protection Agency (EPA) Health Risk Assessment (HRA) model, the American Toxicology and Disease Registry (ATSDR) Target-organ Toxicity Dose (TTD) approach and the ATSDR Binary Weight-of-Evidence (BINWOE) model. Results: The mean ± SD of concentrations of As, Cd, Cr, Cu, Mn, Pb and Zn were (48.90±33.91), (5.95±3.89), (173.57±580.37), (412.71±1 190.00), (612.82±540.70), (297.41±293.22) and (1 052.81±1 156.48) mg/kg, respectively. The HI value of TTD (2.670) and BINWOE (2.933) were higher than the safety threshold of EPA recommended non-carcinogenic health risk. The HI value of TTD and BINWOE were 1.93 and 2.12 times higher than the HI value of HRA (1.386). Conclusion: There was non-carcinogenic health risk of heavy metals (As, Cd, Cr, Cu, Mn, Pb and Zn) via residential indoor dust around the e-waste dismantling area for local children.

[The curative effect of manual reduction combined with vestibular rehabilitation exercise in the treatment of benign paroxysmal positional vertigo].

Objective:To investigate the effect of vestibular rehabilitation exercise combined with manual reduction in the treatment of benign paroxysmal positional vertigo（BPPV）. Method:A total of 186 patients with benign paroxysmal positional vertigo were selected and randomly divided into experimental group and control group . The control group was treated with manual reduction, while the experimental group was treated with manual reduction combined with vestibular rehabilitation exercises. Patients with posterior semicircular canal BPPV carried out Brandt-Daroff exercises, while patients with horizontal semicircular canal BPPV carried out Cawthorne-Cooksey exercises and position restriction. To analyze the clinical curative effect, DHI score, residual dizziness and recurrence of the two groups. Result:There was no significant difference in total efficiency rate and DHI score between the two groups at the first diagnosis（P>0.05）. After 1 week, 2 weeks and 1 month of follow-up, the total efficiency rate of the experimental group were 90.3%, 91.4% and 93.5% respectively, which were significantly higher than those of the control group（P<0.05）. Synchronously, the scores of DHI in experimental group were respectively 14.33±5.71, 12.25±4.98 and 9.45±3.70, which were significantly lower than the control group（P<0.05）. For the experimental group, in the first diagnosis, 1 week, 2 weeks and 1 month after follow-up, residual dizziness patients were 29 cases, 13 cases, 8 cases and 0 cases. The mean duration of residual dizziness was （5.86±4.71） days, which was significantly lower than that in the control group（P<0.05）. One month after follow-up, the recurrence of patients in the experimental group were 5 cases, while the control group were 11 cases, significant difference between the two groups（χ²=4.704, P=0.030）. Conclusion:Manual reduction combined with vestibular rehabilitation exercise can significantly improve the therapeutic effect of BPPV, ameliorate the residual dizziness symptoms and reduce the recurrence rate, meanwhile improve the balance function and quality life of patients.

Absence of Magnetic Thermal Conductivity in the Quantum Spin Liquid Candidate EtMe_{3}Sb[Pd(dmit)_{2}]_{2}.

We present the ultralow-temperature specific heat and thermal conductivity measurements on single crystals of triangular-lattice compound EtMe_{3}Sb[Pd(dmit)_{2}]_{2}, which has long been considered as a gapless quantum spin liquid candidate. In specific heat measurements, a finite linear term is observed, consistent with the previous work [S. Yamashita et al., Nat. Commun. 2, 275 (2011)NCAOBW2041-172310.1038/ncomms1274]. However, we do not observe a finite residual linear term in the thermal conductivity measurements, and the thermal conductivity does not change in a magnetic field of 6 T. These results are in sharp contrast to previous thermal conductivity measurements on EtMe_{3}Sb[Pd(dmit)_{2}]_{2} [M. Yamashita et al., Science 328, 1246 (2010)SCIEAS0036-807510.1126/science.1188200], in which a huge residual linear term was observed and attributed to highly mobile gapless excitations, likely the spinons of a quantum spin liquid. In this context, the true ground state of EtMe_{3}Sb[Pd(dmit)_{2}]_{2} has to be reconsidered.