Hippocampal Crhr1 conditional gene knockout ameliorated the depression-like behavior and pathological damage in male offspring mice caused by chronic stress during pregnancy.

Numerous studies have demonstrated that chronic stress during pregnancy (CSDP) can induce depression and hippocampal damage in offspring. It has also been observed that high levels of corticotropin-releasing hormone (CRH) can damage hippocampal neurons, and intraperitoneal injection of a corticotropin releasing hormone receptor 1 (CRHR1) antagonist decreases depression-like behavior and hippocampal neuronal damage in a mouse depression model. However, whether CSDP causes hippocampal damage and depression in offspring through the interaction of CRH and hippocampal CRHR1 remains unknown and warrants further investigation. Therefore, hippocampal Crhr1 conditional gene knockout mice and C57/BL6J mice were used to study these questions. Depression-related indexs in male offspring mice were examined using the forced swim test (FST), sucrose preference test (SPT), tail suspension test (TST) and open field test (OFT). Serum CRH levels were measured by enzyme-linked immunosorbent assay (ELISA). Golgi-Cox staining was used to examine the morphological changes of hippocampal neuronal dendrites. Neuronal apoptosis in the hippocampal CA3 regions was detected by terminal deoxynucleotidy transferase dUTP nick end labeling (TUNEL) staining. The levels of mammalian target of rapamycin (mTOR), phosphorylated mTOR (p-mTOR) and protein kinase B (AKT) proteins were measured by Western blot analysis. This study showed that CSDP induces depression-like behavior, hippocampal neuronal dendrite damage and apoptosis in male offspring mice. Conditional gene knockout of hippocampal Crhr1 in mice reduced CSDP-induced depression-like behavior, hippocampal neuronal dendrite damage and apoptosis in male offspring, and counteracted the CSDP-induced decreased expression of p-Akt and mTOR activity in male offspring hippocampus. These findings demonstrated that CSDP might inhibit the Akt/mTOR pathway by increasing the levels of CRH, leading to increased CRH-mediated activation of hippocampal CRHR1, thereby inducing synaptic impairment and apoptosis in hippocampal neurons, which in turn leads to depression-like behavior in offspring.

Improved Protein Removal Performance of PES Hollow-Fiber Ultrafiltration Membrane with Sponge-like Structure.

The research used polyethersulfone (PES) as a membrane material, polyvinylpyrrolidone (PVP) k30 and polyethylene glycol 400 (PEG 400) as water-soluble additives, and dimethylacetamide (DMAc) as a solvent to prepare hollow-fiber ultrafiltration membranes through a nonsolvent-induced phase separation (NIPS) process. The hydrophilic nature of PVP-k30 and PEG caused them to accumulate on the membrane surface during phase separation. The morphology, chemical composition, surface charge, and pore size of the PES membranes were evaluated by SEM, FTIR, zeta potential, and dextran filtration experiments. The paper also investigated how different spinning solution compositions affected membrane morphology and performance. The separation efficiency of membranes with four different morphologies was tested in single-protein and double-protein mixed solutions. The protein separation effectiveness of the membrane was studied through molecular weight cutoff, zeta potential, and static protein adsorption tests. In addition, the operating pressure and pH value were adjusted to improve ultrafiltration process conditions. The PES membrane with an intact sponge-like structure showed the highest separation factor of 11, making it a prime candidate membrane for the separation of bovine serum albumin (BSA) and lysozyme (LYS). The membrane had a minimal static protein adsorption capacity of 48 mg/cm2 and had excellent anti-fouling properties. When pH = 4, the BSA retention rate was 93% and the LYS retention rate was 23%. Furthermore, it exhibited excellent stability over a pH range of 1-13, confirming its suitability for protein separation applications.

The usefulness and utilization of Gold-finger retractor for endoscopic thyroid surgery.

Aims: In endoscopic surgery, the visual field is frequently obstructed by muscles, blood, and even smoke. To overcome this problem, we have developed a new detachable Gold-finger retractor for narrow-space surgery. Methods: Gold-finger retractor was used in 30 patients to facilitate surgical field exposure and smoke discharge, while in 27 patients, percutaneous silk thread suspension was employed for the same purpose. Both groups underwent endoscopic unilateral thyroidectomy and unilateral central lymph node dissection via oral vestibular microincision combined with the axillary-assisted approach. A comparative analysis was conducted to evaluate the efficacy of the Gold-finger retractor and silk thread suspension in relation to intraoperative exposure effect, surgical fluency, surgeon's comfort, operation time, postoperative complications, and length of hospital stay. This analysis was based on surgical video recordings and postoperative indicators. Results: With Gold-finger retractor support, surgeons were able to perform meticulous operations. Complication rates were similar between the two groups, and no serious complications occurred. The number of lymph nodes dissected in the Gold-finger group was significantly greater than that in the routine group (12.43 ± 6.18 and 5.7 ± 2.95, respectively). Further analysis of surgeons' comfort (visibility and convenience in peeling) revealed that the Gold-finger group was significantly better. Electrosurgery smoke was removed effectively with Gold-finger, and the operation time was significantly reduced. Conclusion: In thyroid surgery, Gold-fingers enhance visual field resolution, avoid muscle cutting, save time, and improve the surgical experience.

Design, synthesis and biological evaluation of novel 9-methyl-9H-purine and thieno[3, 2-d]pyrimidine derivatives as potent mTOR inhibitors.

The mammalian target of rapamycin (mTOR) has been proved to be an effective target for cancer therapy. Two kinds of mTOR inhibitors, the rapalogs and mTOR kinase inhibitors (TORKi), have been developed and clinically validated in several types of malignancies. Compared with rapalogs, TORKi can exert better antitumor activity by inhibiting both mTORC1 and mTORC2, but the clinical development of current TORKi candidates has been relative slow, more TORKi with novel scaffold need to be developed to expand the current pipelines. In this study, a series of 9-methyl-9H-purine and thieno[3, 2-d]pyrimidine derivatives were designed, synthesized and biological evaluation. Most of these compounds exhibited good mTOR kinase inhibitory activity and selectivity over PI3Kα. Subsequent antiproliferative assay allowed us to identify the lead compound 15i, which display nanomolar to low micromolar IC50s against six human cancer cell lines. 15i could induce cell cycle arrest of MCF-7, PC-3 and A549 cells at the G0/G1 phase and suppress the migration and invasion of these cancer cells by suppressing the phosphorylation of AKT and P70S6 kinase. It could also regulate autophagy-related proteins to induce autophagy. Therefore, 15i would be a starting point for the development of new TORKi as anticancer drug.

Axillary channel-assisted TOETVA: An effective way to prevent mental nerve from iatrogenic injury?

Aim: To evaluate the protective effect of axillary channel-assisted (ACA) transoral endoscopic thyroidectomy vestibular approach on mental nerve. Materials and Methods: From August 2018 to December 2020, 126 cases of thyroid micro-carcinoma patients who underwent endoscopic thyroidectomy were recruited retrospectively. Of those, 74 cases were performed with ACA trans-oral endoscopic thyroidectomy vestibular approach (ACA_TOETVA) (V and A group), 52 cases received standard TOETVA (V group). On postoperative day 1 (POD1), nylon monofilament test and numbness visual analogue scale score were conducted to evaluate the severity of numbness within the mental area, facial expression was tested to determine the motor function of lower mandible and the thickness of cutaneous and subcutaneous layers was measured with ultrasound. The other observation parameters including the time for operation and intraoperative blood loss were carefully collected. Results: On POD1, nylon monofilament test showed that scores in the V and A group (2.9 ± 0.3) were significantly higher than V group (1.7 ± 0.5), P < 0.01, u = 254. The completion percentage of facial expression in the V and A group was 90.5% (67/74) and significantly higher than in V group (21.2%, 11/52), P < 0.01, χ2 = 62.35. The thickness increment of cutaneous and subcutaneous layer was 2.2 ± 1.2 mm in the V and A group, which was significantly less than in the V group (4.0 ± 1.2 mm), P < 0.01, u = 605. Compared with V group, the operation time (113.4 ± 22.3 min vs. 127.7 ± 25.6 min, u = 1262) and intraoperative blood loss (43.5 ± 13.4 ml vs. 51.0 ± 14.1 ml, u = 1355) were also significantly less in the V and A group. Conclusions: The ACA transoral endoscopic thyroidectomy possesses the protective effect on mental nerve and motor function of lower mandible and facilitates the operative procedures of TOETVA.

Decoquinate liposomes: highly effective clearance of Plasmodium parasites causing severe malaria.

BACKGROUND: Severe malaria caused by Plasmodium falciparum leads to most malaria-related deaths globally. Decoquinate (DQ) displays strong activity against multistage infection by Plasmodium parasites. However, the development of DQ as an oral dosage form for the treatment of malaria at the blood stage has not been successful. In this study, liposome formulations of DQ were created for intravenous (IV) injection to suppress Plasmodium berghei, a parasite that causes severe malaria in mice. METHODS: DQ liposomes were prepared by conventional ethanol injection method with slight modifications and encapsulation efficiency evaluated by the well-established centrifugation method. Potency of the DQ liposomes against P. falciparum was assessed in vitro using freshly isolated human red blood cells. The efficacy of the DQ liposomes was examined in the mouse model of severe malaria. RESULTS: The DQ liposomes were around 150 nm in size and had the encapsulation efficiency rates > 95%. The freshly prepared and lyophilized liposomes were stable after storage at - 20 °C for 6 months. The liposomes were shown to have excellent activity against P. falciparum in vitro with DQ IC50 0.91 ± 0.05 nM for 3D7 (chloroquine sensitive strain) and DQ IC50 1.33 ± 0.14 nM for Dd2 (multidrug resistant strain), which were 18- and 14-fold more potent than artemisinin, respectively. Mice did not have any signs of toxicity after receiving high dose of the liposomes (DQ 500 mg/kg per mouse) by IV injection. In the mouse model of severe malaria, the liposomes had impressive efficacy against P. berghei with DQ ED50 of 0.720 mg/kg. CONCLUSION: The DQ liposomes prepared in this study were stable for long term storage and safe for IV injection in mammalian animals. The newly created liposome formulations had excellent activity against Plasmodium infection at the blood-stage, which encourages their application in the treatment of severe malaria.

Influence of combined exposure levels of total arsenic and inorganic arsenic on arsenic methylation capacity among university students: findings from Bayesian kernel machine regression analysis.

The arsenic (As) methylation capacity is an important determinant of susceptibility to As-related diseases. Total As (TAs) or inorganic As (iAs) was reported to associated with As methylation capacity. We measured urinary concentrations of iAs, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) by using HPLC-HG-AFS and calculated the primary methylation capacity index (PMI) and secondary methylation capacity index (SMI) in 209 university students in Hefei, China, a non-As endemic area. Volunteers were given a standardized questionnaire asking about their sociodemographic characteristics. Bayesian kernel machine regression (BKMR) analysis was used to estimate the association of lnTAs and lniAs levels with methylation indices (ln%MMA, ln%DMA, lnPMI, lnSMI). The median concentrations of iAs, MMA, and DMA were 1.22, 0.92, and 12.17 µg/L, respectively; the proportions of iAs, MMA, and DMA were 8.76%, 6.13%, and 84.84%, respectively. Females had higher %DMA and lower %MMA than males. The combined levels of lnTAs and lniAs showed a decrease in the changes in ln%DMA and lnSMI. With regard to the single exposure level, the lnTAs showed positive correlations with ln%DMA, lnPMI, and lnSMI when lniAs was set at a specific level, while lniAs showed negative correlations with ln%DMA, lnPMI, and lnSMI when lnTAs was set at a specific level; all the dose-response relationships were nonlinear. Our results suggested that combined levels of TAs and iAs play an important role in reducing As methylation capacity, especially iAs, and the reduction only occurs when TAs and iAs are present up to a certain combined level.

Comprehensive analysis of the significance of METTL7A gene in the prognosis of lung adenocarcinoma.

Background: The most common subtype of lung cancer, called lung adenocarcinoma (LUAD), is also the largest cause of cancer death in the world. The aim of this study was to determine the importance of the METTL7A gene in the prognosis of patients with LUAD. Methods: This particular study used a total of four different LUAD datasets, namely TCGA-LUAD, GSE32863, GSE31210 and GSE13213. Using RT-qPCR, we were able to determine METTL7A expression levels in clinical samples. Univariate and multivariate Cox regression analyses were used to identify factors with independent effects on prognosis in patients with LUAD, and nomograms were designed to predict survival in these patients. Using gene set variation analysis (GSVA), we investigated differences in enriched pathways between METTL7A high and low expression groups. Microenvironmental cell population counter (MCP-counter) and single-sample gene set enrichment analysis (ssGSEA) methods were used to study immune infiltration in LUAD samples. Using the ESTIMATE technique, we were able to determine the immune score, stromal score, and estimated score for each LUAD patient. A competing endogenous RNA network, also known as ceRNA, was established with the help of the Cytoscape program. Results: We detected that METTL7A was down-regulated in pan-cancer, including LUAD. The survival study indicates that METTL7A was a protective factor in the prognosis of LUAD. The univariate and multivariate Cox regression analyses revealed that METTL7A was a robust independent prognostic indicator in survival prediction. Through the use of GSVA, several immune-related pathways were shown to be enriched in both the high-expression and low-expression groups of METTL7A. Analysis of the tumor microenvironment revealed that the immune microenvironment of the group with low expression was suppressed, which may be connected to the poor prognosis. To explore the ceRNA regulatory mechanism of METTL7A, we finally constructed a regulatory network containing 1 mRNA, 2 miRNAs, and 5 long non-coding RNAs (lncRNAs). Conclusion: In conclusion, we presented METTL7A as a potential and promising prognostic indicator of LUAD. This biomarker has the potential to offer us with a comprehensive perspective of the prediction of prognosis and treatment for LUAD patients.

Clinical application of local anesthesia for TiRobot-assisted removal of sacroiliac screws / 中华创伤骨科杂志

Objective:To explore the feasibility and advantages and disadvantages of local anesthesia for TiRobot-assisted removal of sacroiliac screws by comparison with general anesthesia for TiRobot-assisted removal of sacroiliac screws.Methods:A retrospective study was performed in 39 patients with posterior pelvic ring fracture-dislocation who had undergone removal of percutaneous sacroiliac screws after fracture union from January 2017 to December 2020 at Department of Orthopaedic Surgery, Hospital Affiliated to Chengdu University. Their sacroiliac screws were removed with TiRobot assistance under local anesthesia (LA group) or general anesthesia (GA group). In the LA group of 18 cases, there were 10 males and 8 females, aged (43.3 ± 8.4) years (from 25 to 58 years); in the GA group of 21 cases, there were 12 males and 9 females, aged (44.9 ± 9.0) years (from 23 to 60 years). The 2 groups were compared in terms of time for planning screw removal path, fluoroscopy frequency, fluoroscopy time, operation time, anesthesia time, anesthesia cost, postoperative visual analogue scale (VAS) and postoperative ambulation time.Results:There was no statistically significant difference in baseline data between the 2 groups, showing comparability ( P>0.05). Follow-ups revealed grade A wound healing in all patients. There were no significant differences between the 2 groups in time for planning screw removal path, fluoroscopy frequency, fluoroscopy time or operation time ( P>0.05). The anesthesia time [(41.6 ± 8.3) min], anesthesia cost [(653.5 ± 102.6) yuan] and postoperative ambulation time [(2.6 ± 0.6) h] in the LA group were significantly less than those in the GA group [(52.3 ± 9.5) min, (2,475.6 ± 261.8) yuan and (8.7 ± 2.4) h] while the VAS score in the former group (3.8 ± 1.5) was significantly higher than that in the latter group (2.5 ± 1.3) (all P<0.05). Conclusions:It is feasible to use local anesthesia for TiRobot-assisted removal of sacroiliac screws. In TiRobot-assisted removal of sacroiliac screws, compared with general anesthesia, local anesthesia may lead to shorter anesthesia time, lower anesthesia cast and shorter ambulation time, but the patients need to be compliant enough.

Childhood Clear Cell Sarcoma of Kidney: Incidence and Survival.

This study is to describe current incidence of childhood clear cell sarcoma of kidney (CCSK) and to investigate the present survival of this cancer. Surveillance, Epidemiology, and End Result (SEER) data was used to identify children with CCSK and Wilms tumor (WT) aged 0-19 years in the US. Age-adjusted incidences were estimated over the decades. Age- and sex-specific epidemiology was also presented. Propensity score matching was used to balance features of CCSK and WT cases. Log rank test was used to compare survivals and Cox regression was used to evaluate independent effects of factors. The present age-adjusted incidence of childhood CCSK was 0.205 per million, which remained stable for years and ranked third in all pediatric renal tumors. The incidence rate ratios for boy and age under 4 were 3 and 21, respectively. The current 5-year overall survival (OS) rate for CCSK was 87%, which is not evidently inferior to that for WT (90%); however the outcome of CCSK was significantly poorer if both groups were well-balanced (OS rate was 86 vs. 95%). Early year of diagnosis and distant metastasis were independent survival factors. In conclusion, occurrence of CCSK remains stable over the years, with an age-adjusted incidence of 0.205 per million. Boy and age under 4 are risk factors for tumor development. CCSK currently has a favorable outcome but its nature may be more aggressive than common kidney tumor, which in turn proves efficacy of modern treatment.

Two mechanically ventilated cases of COVID-19 successfully managed with a sequential ventilation weaning protocol: Two case reports.

BACKGROUND: Patients with critical coronavirus disease 2019 (COVID-19), characterized by respiratory failure requiring mechanical ventilation (MV), are at high risk of mortality. An effective and practical MV weaning protocol is needed for these fragile cases. CASE SUMMARY: Here, we present two critical COVID-19 patients who presented with fever, cough and fatigue. COVID-19 diagnosis was confirmed based on blood cell counts, chest computed tomography (CT) imaging, and nuclei acid test results. To address the patients' respiratory failure, they first received noninvasive ventilation (NIV). When their condition did not improve after 2 h of NIV, each patient was advanced to MV [tidal volume (Vt), 6 mL/kg ideal body weight (IBW); 8-10 cmH2O of positive end-expiratory pressure; respiratory rate, 20 breaths/min; and 40%-80% FiO2] with prone positioning for 12 h/day for the first 5 d of MV. Extensive infection control measures were conducted to minimize morbidity, and pharmacotherapy consisting of an antiviral, immune-enhancer, and thrombosis prophylactic was administered in both cases. Upon resolution of lung changes evidenced by CT, the patients were sequentially weaned using a weaning screening test, spontaneous breathing test, and airbag leak test. After withdrawal of MV, the patients were transitioned through NIV and high-flow nasal cannula oxygen support. Both patients recovered well. CONCLUSION: A MV protocol attentive to intubation/extubation timing, prone positioning early in MV, infection control, and sequential withdrawal of respiratory support, may be an effective regimen for patients with critical COVID-19.

Light therapy in non-seasonal depression: An update meta-analysis.

The effect of light therapy in treating seasonal affective disorder has been demonstrated amongst previous studies. However, the effect of light therapy in treating non-seasonal depression remains unclear. This meta-analysis aimed to determine the efficacy of light therapy in non-seasonal depression. We searched for randomized controlled trials (RCTs) in the PubMed, Web of Science, Chinese National Knowledge Infrastructure, and Chinese Biomedical Database up to February 2020. The pooled post-trial standardized mean difference in depression scores with corresponding 95% confidence intervals was calculated to evaluate the efficacy of light therapy in non-seasonal depression. A total of 23 RCTs with 1120 participants were included. The meta-analysis demonstrated the light therapy was significantly more effective than comparative treatments. Subgroup analyses revealed that none of the factors explained the significantly heterogeneity. Light therapy has a statistically significant mild to moderate treatment effect in reducing depressive symptoms, can be used as a clinical therapy in treating non-seasonal depression. But the quality of evidence is still low, more well-designed studies with larger sample size and high quality are needed to confirm the efficiency of light therapy in treating non-seasonal depression.

[A multicenter survey of antibiotic use in very and extremely low birth weight infants in Hunan Province].

OBJECTIVE: To investigate the current status of antibiotic use for very and extremely low birth weight (VLBW/ELBW) infants in neonatal intensive care units (NICUs) of Hunan Province. METHODS: The use of antibiotics was investigated in multiple level 3 NICUs of Hunan Province for VLBW and ELBW infants born between January, 2017 and December, 2017. RESULTS: The clinical data of 1 442 VLBW/ELBW infants were collected from 24 NICUs in 2017. The median antibiotic use duration was 17 days (range: 0-86 days), accounting for 53.0% of the total length of hospital stay. The highest duration of antibiotic use was up to 91.4% of the total length of hospital stay, with the lowest at 14.6%. In 16 out of 24 NICUs, the antibiotic use duration was accounted for more than 50.0% of the hospitalization days. There were 113 cases with positive bacterial culture grown in blood or cerebrospinal fluid, making the positive rate of overall bacterial culture as 7.84%. The positive rate of bacterial culture in different NICUs was significantly different from 0% to 14.9%. The common isolated bacterial pathogens Klebsiella pneumoniae was 29 cases (25.7%); Escherichia coli 12 cases (10.6%); Staphylococcus aureus 3 cases (2.7%). The most commonly used antibiotics were third-generation of cephalosporins, accounting for 41.00% of the total antibiotics, followed by penicillins, accounting for 32.10%, and followed by carbapenems, accounting for 13.15%. The proportion of antibiotic use time was negatively correlated with birth weight Z-score and the change in weight Z-score between birth and hospital discharge (rs=-0.095, -0.151 respectively, P<0.01), positively correlated with death/withdrawal of care (rs=0.196, P<0.01). CONCLUSIONS: Antibiotics used for VLBW/ELBW infants in NICUs of Hunan Province are obviously prolonged in many NICUs. The proportion of routine use of third-generation of cephalosporins and carbapenems antibiotics is high among the NICUs.

Simulating and Forecasting the Cumulative Confirmed Cases of SARS-CoV-2 in China by Boltzmann Function-based Regression Analyses

An ongoing outbreak of atypical pneumonia caused by the 2019 novel coronavirus (SARS-CoV-2) is hitting Wuhan City and has spread to other provinces/cities of China and overseas. It very urgent to forecast the future course of the outbreak. Here, we provide an estimate of the potential total number of confirmed cases in mainland China by applying Boltzmann-function based regression analyses. We found that the cumulative number of confirmed cases from Jan 21 to Feb 14, 2020 for mainland China, Hubei Province, Wuhan City and other provinces were all well fitted with the Boltzmann function (R2 being close to 0.999). The potential total number of confirmed cases in the above geographic regions were estimated at 95% confidence interval (CI) as 79589 (71576, 93855), 64817 (58223, 77895), 46562 (40812, 57678) and 13956 (12748, 16092), respectively. Notably, our results suggest that the number of daily new confirmed cases of SARS-CoV-2 in mainland China (including Hubei Province) will become minimal between Feb 28 and Mar 10, 2020, with 95% CI. In addition, we found that the data of cumulative confirmed cases of 2003 SARS-CoV in China and Worldwide were also well fitted to the Boltzmann function. To our knowledge this is the first study revealing that the Boltzmann function is suitable to simulate epidemics. The estimated potential total number of confirmed cases and key dates for the SARS-CoV-2 outbreak may provide certain guidance for governments, organizations and citizens to optimize preparedness and response efforts.

Content Determination of Related Substances in Paracetamol Tablets by HPLC / 中国药房

OBJECTIVE：To establish the method for content determination of related substances in Paracetamol tablets. METHODS：HPLC method was adopted. The determination was performed on Agilent 5HC-C8 column with mobile phase A consisted of methanol-water-glacial acetic acid （50 ∶ 950 ∶ 1，V/V/V）and mobile phase B consisted of methanol-water-glacial acetic acid（500 ∶ 500 ∶ 1，V/V/V）（gradient elution ）at the flow rate of 0.9 mL/min. The detection wavelength was set at 254 nm，and column temperature was 40 ℃. The sample size was 5 μL. RESULTS：Under the chromatographic condition ，the resolutions of main component （paracetamol），6 known impurities （p-aminophenol，p-chloroacetanilide，impurity A ，B，D，F），3 specific excipients（methyl hydroxybenzoate ，ethyl hydroxybenzoate ，propyl hydroxybenzoate ）and 1 unknown impurity were all higher than 1.5. The linear range of 6 known impurities were 0.539-1.617，0.026-0.384，0.237-17.799，0.257-19.271，0.239-17.955， 0.246-18.462 μg/mL（r≥0.999 8），respectively. Correction factors of impurity A ，B，D，F were 2.9，1.0，1.2，6.2. The limits of detection were 0.009 6，0.024 2，0.164 0，0.051 1，0.055 9，0.422 0 ng；the limits of quantitation were 0.032 0，0.080 6，0.546 0，0.170 0，0.186 0，1.406 0 ng. Average recoveries were 95.96％-111.09％（RSDs were 0.05％-2.42％）. The RSDs precision test were low than 15％，and the durability were good. p-aminophenol（all were 0.006％），impurity B （0.016％-0.017％）and unknown impurity（0.002 0％-0.002 1％）were detected in 3 batches of sample. p-choroacetanilide，impurity A ，D and F were not detected. CONCLUSIONS：The method is specific ，accurate and suitable for the determination of related substance in Paracetamol tablets.

Gate-tunable optical filter based on conducting oxide metasurface heterostructure.

A gate-tunable plasmonic optical filter incorporating a subwavelength patterned metal-insulator-metal metasurface heterostructure is proposed. An additional thin transparent conducting oxide (TCO) layer is embedded in the insulator layer to form a double metal-oxide-semiconductor configuration. Heavily n-doped indium tin oxide (ITO) is employed as the TCO material, whose optical property can be electrically tuned by the formation of a thin active epsilon-near-zero layer at the ITO-oxide interfaces. Full-wave electromagnetic simulations show that amplitude modulation and shift of transmission peak are achievable with 3-5 V applied bias, depending on the application. Moreover, the modulation strength and transmission peak shift increase with a thinner ITO layer. This work is an essential step toward a realization of next-generation compact photonic/plasmonic integrated devices.

Gate-Tunable Plasmon-Induced Transparency Modulator Based on Stub-Resonator Waveguide with Epsilon-Near-Zero Materials.

We demonstrate an electrically tunable ultracompact plasmonic modulator with large modulation strength (>10 dB) and a small footprint (~1 µm in length) via plasmon-induced transparency (PIT) configuration. The modulator based on a metal-oxide-semiconductor (MOS) slot waveguide structure consists of two stubs embedded on the same side of a bus waveguide forming a coupled system. Heavily n-doped indium tin oxide (ITO) is used as the semiconductor in the MOS waveguide. A large modulation strength is realized due to the formation of the epsilon-near-zero (ENZ) layer at the ITO-oxide interface at the wavelength of the modulated signal. Numerical simulation results reveal that such a significant modulation can be achieved with a small applied voltage of ~3V. This result shows promise in developing nanoscale modulators for next generation compact photonic/plasmonic integrated circuits.

Prophylactic abdominal aortic balloon occlusion: An effective method of controlling hemorrhage in patients with placenta previa or accreta.

Postpartum hemorrhage is considered to be a serious complication in patients with pernicious placenta. Approaches employing abdominal aortic balloon occlusion to control hemorrhage are extremely effective for such patients. The present study analyzed 9 patients with pernicious placenta previa in a single hospital from June 2016 to November 2017. Prior to cesarean hysterectomy, an abdominal aortic balloon catheter was placed in all patients. The balloon was inflated and evacuated alternately using saline following delivery of the fetal head. The X-ray dose, bleeding volume and complications during the procedure were observed. Balloon catheterization was successfully performed in all 9 patients. The dose of X-rays ranged from 15.8 to 24.5 mGy, with a mean of 19.3±2.7 mGy; the volume of blood loss ranged from 50 to 4,000 ml, with a mean of ~1,800 ml. Uterine artery embolization was successfully performed in 2 cases due to bleeding following the cesarean hysterectomy, and every uterus was retained. Abdominal aortic balloon occlusion can effectively reduce the amount of bleeding during cesarean hysterectomy in patients with pernicious placenta previa. This may serve as technical support for patients in whom retention of the uterus is expected. However, it is necessary to identify any abnormal uterine tissue above the level of the renal artery in order to avoid ineffective balloon occlusion.

Problems and solutions in clinical practice of orthopedics for medical students / 中华医学教育探索杂志

In view of problems such as students in clinical orthopedic practice lack of basic theoretical knowledge and practical ability, both teachers and students' lack of preparations for clinical practice and their insufficient attention etc., this paper attempts to strengthen the standardized management of department teaching. Some measures were adopted to stimulate the potential of students, such as teaching based on case combination, department discussion, strengthening education of humanities, improving examination methods and so on, so as to improve students' comprehensive ability and achieve teaching goals. The results showed that by changing the above teaching methods, students can improve their mastery of knowledge, proficiency in basic operation, clinical thinking ability, communication and coordination ability, subjective initiative and so on. At the same time, students' problem-solving ability, learning interests, self-confidence and the satisfaction with teaching effect have also been improved, which promoted the performance of students in clinical practice.

Advantages and security of sacroiliac lag screwing assisted by an orthopaedic TiRobot / 中华创伤骨科杂志

Objective To explore the advantages and security of orthopaedic TiRobot used to assist internal fixation with sacroiliac lag screws.Methods From December 2015 to August 2017,11 patients with fracture of pelvic posterior ring or sacroiliac separation were treated by internal fixation with sacroiliac lag screws assisted by an orthopaedic TiRobot at Department of Orthopaedic Surgery,Affiliated Hospital to Chengdu University.They were 7 men and 4 women,aged from 23 to 61 years (average,42.5 years).According to AO classification,there were one case of type B1.2,one case of type B2.2,6 cases of type C1.2,2 cases of type C1.3 and one case of type C2.3.The number of sacroiliac lag screws inserted,time for planning insertion approaches,fluoroscopy frequency,fluoroscopy time,exposure time of C-arm X-ray,operation time,blood loss and reduction quality were documented.Results The 11 patients were followed up for 5 to 22 months (average,9.5 months).A total of 15 sacroiliac screws were inserted.In the operations,time for planning insertion approaches averaged 8.5 minutes (from 9 to 25 minutes),fluoroscopy frequency 8.5 times (from 4 to 15 times),fluoroscopy time 5.5 minutes (from 3.2 to 6.5 minutes),exposure time of C-arm X-ray machine 5.8 seconds (from 2.4 to 16.3 seconds),operation time 34.5 minutes (from 25 to 45 minutes),and blood loss 35 mL (from 10 to 80 mL).All the screw positions were satisfactory,with no penetration into the sacral canal,sacral foramen or bone cortex.No postoperative neurovascular injury happened.All the incisions primarily healed.All the fractures united well after 4 to 7 months (average,5.6 months),without any screw loosening.By the Matta scoring for fracture reduction,9 cases were excellent,one was good and one fair.By the Majeed functional scoring for pelvic fractures,8 cases were rated as excellent and 3 as good at the last follow-up.Conclusion Orthopaedic TiRobots can be used to assist internal fixation with sacroiliac lag screws in the treatment of pelvic posterior ring injuries,with advantages of limited invasion,time,hemorrhage,and high safety and accuracy as well.