[Automatic determination of mandibular landmarks based on three-dimensional mandibular average model].

OBJECTIVE: To explore an efficient and automatic method for determining the anatomical landmarks of three-dimensional(3D) mandibular data, and to preliminarily evaluate the performance of the method. METHODS: The CT data of 40 patients with normal craniofacial morphology were collected (among them, 30 cases were used to establish the 3D mandibular average model, and 10 cases were used as test datasets to validate the performance of this method in determining the mandibular landmarks), and the 3D mandibular data were reconstructed in Mimics software. Among the 40 cases of mandibular data after the 3D reconstruction, 30 cases that were more similar to the mean value of Chinese mandibular features were selected, and the size of the mandibular data of 30 cases was normalized based on the Procrustes analysis algorithm in MATLAB software. Then, in the Geomagic Wrap software, the 3D mandibular average shape model of the above 30 mandibular data was constructed. Through symmetry processing, curvature sampling, index marking and other processing procedures, a 3D mandible structured template with 18 996 semi-landmarks and 19 indexed mandibular anatomical landmarks were constructed. The open source non-rigid registration algorithm program Meshmonk was used to match the 3D mandible template constructed above with the tested patient's 3D mandible data through non-rigid deformation, and 19 anatomical landmark positions of the patient's 3D mandible data were obtained. The accuracy of the research method was evaluated by comparing the distance error of the landmarks manually marked by stomatological experts with the landmarks marked by the method of this research. RESULTS: The method of this study was applied to the data of 10 patients with normal mandibular morphology. The average distance error of 19 landmarks was 1.42 mm, of which the minimum errors were the apex of the coracoid process [right: (1.01±0.44) mm; left: (0.56±0.14) mm] and maximum errors were the anterior edge of the lowest point of anterior ramus [right: (2.52±0.95) mm; left: (2.57±1.10) mm], the average distance error of the midline landmarks was (1.15±0.60) mm, and the average distance error of the bilateral landmarks was (1.51±0.67) mm. CONCLUSION: The automatic determination method of 3D mandibular anatomical landmarks based on 3D mandibular average shape model and non-rigid registration algorithm established in this study can effectively improve the efficiency of automatic labeling of 3D mandibular data features. The automatic determination of anatomical landmarks can basically meet the needs of oral clinical applications, and the labeling effect of deformed mandible data needs to be further tested.

[Preliminary evaluation of the trueness of 5 chairside 3D facial scanning techniques].

OBJECTIVE: To quantitatively evaluate the trueness of five chairside three-dimensional facial scanning techniques, and to provide reference for the application of oral clinical diagnosis and treatment. METHODS: The three-dimensional facial data of the subjects were collected by the traditional professional three-dimensional facial scanner Face Scan, which was used as the reference data of this study. Four kinds of portable three-dimensional facial scanners (including Space Spider, LEO, EVA and DS-FScan) and iPhone Ⅹ mobile phone (Bellus3D facial scanning APP) were used to collect three-dimensional facial data from the subjects. In Geomagic Studio 2013 software, through data registration, deviation analysis and other functions, the overall three-dimensional deviation and facial partition three-dimensional deviation of the above five chairside three-dimensional facial scanning technologies were calculated, and their trueness performance evaluated. Scanning time was recorded during the scanning process, and the subject's comfort was scored by visual analogue scale(VAS). The scanning efficiency and patient acceptance of the five three-dimensional facial scanning techniques were evaluated. RESULTS: DS-FScan had the smallest mean overall and mean partition three-dimensional deviation between the test data and the reference data, which were 0.334 mm and 0.329 mm, respectively. The iPhone Ⅹ mobile phone had the largest mean overall and mean partition three-dimensional deviation between the test data and the reference data, which were 0.483 mm and 0.497 mm, respectively. The detailed features of the three-dimensional facial data obtained by Space Spider were the best. The iPhone Ⅹ mobile phone had the highest scanning efficiency and the highest acceptance by the subject. The average scanning time of the iPhone Ⅹ mobile phone was 14 s, and the VAS score of the subjects' scanning comfort was 9 points. CONCLUSION: Among the five chairside three-dimensional face scanning technologies, the trueness of the scan data of the four portable devices had no significant difference, and they were all better than the iPhone Ⅹ mobile phone scan. The subject with the iPhone Ⅹ scanning technology had the best expe-rience.

[Research progress on the role of type II innate lymphoid cells in liver diseases].

Type II innate lymphoid cell (ILC2) is a newly identified innate immunological cell that belongs to the lymphocyte lineage in cell morphology, resides in the body's mucosal tissues, and has the dual functions of innate and adaptive immunity to promote tissue remodeling and repair after injury. Additionally, it is involved in the occurrence and development of a variety of liver diseases and plays an important role in maintaining the immunological homeostasis of the liver region. This article reviews the differentiation, development, and biological functions of ILC2, with particular attention to the research progress in liver diseases.

[Deep learning-assisted construction of three-demensional facial midsagittal plane].

OBJECTIVE: To establish a deep learning algorithm that can accurately determine three-dimensional facial anatomical landmarks, multi-view stacked hourglass convolutional neural networks (MSH-CNN) and to construct three-dimensional facial midsagittal plane automatically based on MSH-CNN and weighted Procrustes analysis algorithm. METHODS: One hundred subjects with no obvious facial deformity were collected in our oral clinic. Three-dimensional facial data were scanned by three-dimensional facial scanner. Experts annotated twenty-one facial landmarks and midsagittal plane of each data. Eighty three-dimensional facial data were used as training set, to train the MSH-CNN in this study. The overview of MSH-CNN network architecture contained multi-view rendering and training the MSH-CNN network. The three-dimensional facial data were rendered from ninety-six views that were fed to MSH-CNN and the output was one heatmap per landmark. The result of the twenty-one landmarks was accurately placed on the three-dimensional facial data after a three-dimensional view ray voting process. The remaining twenty three-dimensional facial data were used as test set. The trained MSH-CNN automatically determined twenty-one three-dimensional facial anatomical landmarks of each case of data, and calculated the distance between each MSH-CNN landmark and the expert landmark, which was defined as position error. The midsagittal plane of the twenty subjects' could be automatically constructed, using the MSH-CNN and Procrustes analysis algorithm. To evaluate the effect of midsagittal plane by automatic method, the angle between the midsagittal plane constructed by the automatic method and the expert annotated plane was calculated, which was defined as angle error. RESULTS: For twenty subjects with no obvious facial deformity, the average angle error of the midsagittal plane constructed by MSH-CNN and weighted Procrustes analysis algorithm was 0.73°±0.50°, in which the average position error of the twenty-one facial landmarks automatically determined by MSH-CNN was (1.13±0.24) mm, the maximum position error of the orbital area was (1.31±0.54) mm, and the minimum position error of the nasal area was (0.79±0.36) mm. CONCLUSION: This research combines deep learning algorithms and Procrustes analysis algorithms to realize the fully automated construction of the three-dimensional midsagittal plane, which initially achieves the construction effect of clinical experts. The obtained results constituted the basis for the independent intellectual property software development.

[Preliminary clinical application verification of complete digital workflow of design lips symmetry reference plane based on posed smile].

OBJECTIVE: To automatically construct lips symmetry reference plane (SRP) based on posed smile, and to evaluate its advantages over conventional digital aesthetic design. METHODS: Eighteen subjects' three-dimensional facial and dentition data were gathered in this study. The lips SRP of experimental groups were used with the standard weighted Procrustes analysis (WPA) algorithm and iterative closest point (ICP), respectively. A reference plane defined by experts based on regional ICP algorithm, served as the truth plane. The angle error values between the lips SRP of WPA algorithm in the experimental groups and the truth plane were evaluated in this study, and the lips SRP of ICP algorithm of the experimental groups was calculated in the same way. The lips SRP based on posed smile as a reference for aesthetic design and evaluate preliminary clinical application. RESULTS: The average angle error between the lips SRP of WPA algorithm and the truth plane was 1.78°±1.24°, which was smaller than that between the lips SRP of ICP and the truth plane 7.41°±4.31°. There were significant differences in the angle errors among the groups (P < 0.05). In the aesthetic design of anterior teeth, automatically constructing the lips SRP of WPA algorithm based on posed smile and the original symmetry plane by re-ference compared with the prosthetic design, the subjects' scores on the lips SRP of WPA algorithm based on posed smile (8.48±0.57) were higher than those on the original symmetry plane (5.20±1.31). CONCLUSION: Automatically constructing the lips SRP of WPA algorithm based on posed smile was more accurate than ICP algorithm, which was consistent with the truth plane. Moreover, it can provide an important reference for oral aesthetic diagnosis and aesthetic analysis of the restoration effect. In the aesthetic design of anterior teeth, automatically constructing the lips SRP of WPA algorithm based on posed smile can improve the patients' satisfaction in esthetic rehabilitation.

[Value of tumor growth rate in evaluating the early therapeutic efficacy of neuroendocrine neoplasm].

Objective: To determinate the value of tumor growth rate (TGR) in evaluating the efficacy of early drug treatment for neuroendocrine neoplasm (NEN). Methods: Patients with NEN who treated at Chinese Academy of Medical Sciences Cancer Hospital from January 2010 to December 2018 were retrospectively enrolled. A total of 30 patients (16 males and 14 females, aged from 26 to 73 (53±11) years) were enrolled. The sum of largest diameter of target lesions and the interval time were measured, TGR of 3 months after the first treatment was calculated using a formula. Intraclass correlation coefficient (ICC) were used to test the repeatability of TGR. Receiver operating characteristic curve (ROC) analysis was used to determine the optimal cut-off values of TGR for predicting progression-free survival (PFS). Overall patients and SD patients assessed by RECIST were grouped by the optimal cut-off values of TGR. Kaplan-Meier method was used to estimate PFS rates and plot patient survival curves of patients at different group of TGR. Cox risk proportional hazard model was used to assess the effect of TGR on the prognosis. Results: The optimal cut-off value of TGR was -5.8(%/m), the area under the curve was 0.921 (95%CI: 0.824-0.999, P<0.001). Interobserver ICC was 0.955 (95%CI: 0.907-0.978,P<0.001). Multivariate Cox analysis showed that compared with the patients with TGR<-5.8, the patients with TGR ≥-5.8 had a higher risk of progression in either overall population (HR: 10.906, 95%CI: 1.953-60.898, P=0.006) or the SD population (HR: 14.354, 95%CI: 1.602-128.627, P=0.017); TGR ≥-5.8 was an independent risk factor affecting the prognosis of NEN. Conclusions: TGR can evaluate the efficacy of NEN's early anti-tumor drug treatment, and associate with prognosis.

[Analysis and significance of HBV DNA below the lower detection limit of HBV RNA levels after long-term NAs antiviral therapy in patients with hepatitis B virus cirrhosis].

Objective: To analyze the significance of HBV DNA below the lower detection limit of HBV RNA levels after long-term nucleos(t)ide analogues (NAs) antiviral therapy in patients with hepatitis B virus cirrhosis. Methods: 97 cases with hepatitis B virus cirrhosis treated with NAs antiviral therapy for at least 3 years between May 2018 to July 2019 were selected. High-sensitivity HBV DNA (<20 IU/ml), alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (GGT), HBsAg, HBeAg and HBV RNA at least twice every 6 months were detected. According to Child-Pugh classification, HBeAg, HBsAg level, and HBV RNA level intergroup comparison was performed. Rank sum test, χ2 test and linear regression analysis were performed on the data. Results: Compared with the HBV RNA level of child-Pugh class A patients, the HBV RNA level of Child-Pugh class B+C patients were significantly higher [4.1 (0,4.9) log10 copies/ml and 2.0 (0,3.5) log10 copies/ml], and the difference was statistically significant (Z=2.370, P<0.05). According to different HBeAg levels, they were divided into HBeAg positive and negative group, and the quantitative comparison of HBV RNA levels between the two groups were 2.0 (0, 4.5) log10 copies/ml and 1.0 (1.0, 2.0) log10 copies/ml, respectively, and the difference was statistically significant (Z=3.233, P<0.05). According to different HBsAg levels, they were divided into three groups: HBsAg≤100 IU/ml, 100

[Diagnostic value of surgical lung biopsies for diffuse parenchymal lung disease: the change of disease spectrum in the past 28 years in a single institution in China].

Objective: To investigate the changes of disease spectrum in diffuse parenchymal lung disease (DPLD) diagnosed by surgical lung biopsy, and to explore the diagnostic value of surgical lung biopsy in DPLD. Methods: Four hundred and fifty-five consecutive DPLD patients, who underwent surgical lung biopsy in Peking Union Medical College Hospital during the past 28 years, were analyzed retrospectively. Results: There were 211 males and 244 females. The average age at biopsy was (45±14) years. Four hundred and eleven cases (90.3%) were diagnosed by pathologic findings. Four hundred and forty-one cases (96.9%) were diagnosed by clinical-radiologic-pathologic multidisciplinary discussion. The 30-day mortality and 90-day mortality were 2.4% and 3.3% respectively. The disease spectrum included interstitial pneumonia in 209 cases (45.9%) (nonspecific interstitial pneumonia in 105 cases, usual interstitial pneumonia in 33 cases), other miscellaneous DPLD in 166 cases (36.5%) (including hypersensitivity pneumonitis in 49 cases), tumor in 39 cases (8.6%), and infectious diseases in 27 cases (5.9%). In the three consecutive periods (1993-2002, 2003-2012 and 2013-2020), the number of biopsies was 76 (16.7%), 297 (65.3%) and 82 (18%) respectively. The disease spectrum changes over time: in the above three periods, the percentage of interstitial pneumonia in DPLD was 68.4%, 45.1% and 28%, other miscellaneous DPLDs were 22.4%, 39.4% and 39.0%, the tumors were 2.6%, 7.4% and 18.3%, the infectious diseases were 5.3%, 5.1% and 9.8%. Conclusions: This study presented the changes of disease spectrum in DPLD diagnosed by surgical lung biopsy through single center real-world data, reflecting the progress of clinicians' understanding of DPLD and interstitial pneumonia. Surgical lung biopsy is still valuable for some difficult and complicated DPLD cases.

[Subcutaneous nodules, mediastinal and hilar lymphadenopathy].

A 52-year old man was admitted to our hospital because of dyspnea on exertion for 2 months and subcutaneous nodules for 1 month. Chest enhanced CT showed bilateral hilar and mediastinal lymphadenopathy. Bronchial alveolar lavage fluid revealed a CD4+/CD8+ T cell subsets ratio of 4.3 and culture for acid-fast bacillus (AFB) was negative. The pathology of skin nodules and transbronchial needle aspiration biopsy guided by endoscopic ultrasound (EBUS-TBNA) revealed non-caseating necrotizing epithelioid granulomas with negative acid-fast bacilli staining and periodic acid-Schiff staining, which was compatible with sarcoidosis. The patient was diagnosed as sarcoidosis and glucocorticoid was administrated. The subcutaneous nodules were improved. However, the lymph nodes were enlarged instead of shrinking after 6-month therapy. The failure to respond to glucocorticoids raised the possibility of sarcoidosis complicated with tuberculosis infection. The patient received anti-tuberculosis therapy. Lymphadenopathy responded within 4 months, and there was complete regression after 18-month treatment. The patient was followed up for 5 years and repeated chest CT scan showed that the sizes of bilateral hilar and mediastinal lymph nodes were normal.

[Value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid enhanced magnetic resonance imaging and diffusion-weighted MR imaging in predicting microvascular invasion in hepatocellular carcinoma and the prognostic significance].

Objective: To investigate the combined value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in predicting pathological microvascular invasion (pMVI) preoperatively, and to determine the relationship between prediction results and prognosis in hepatocellular carcinoma (HCC) patients. Methods: A total of 181 newly diagnosed HCC patients were enrolled in this study. Imaging characteristics and the apparent diffusion coefficient (ADC) value of DWI were analyzed. The differences of imaging characteristics and ADC values between different pMVI groups were analyzed.Multivariate logistic regression and receiver operating characteristic (ROC) curve were used to analyze the value for pMVI prediction by using significant parameters. The patients were grouped based on MRI predicted MVI (mrMVI), and the relationship between mrMVI and recurrence free survival time (RFS) was analyzed. Results: Fifty-one patients were pMVI positive and 130 patients were pMVI negative. The ADC value in pMVI positive group were (1.10±0.17)×10(-3) mm(2)/s, significantly lower than (1.27±0.22)×10(-3) mm(2)/s of pEMVI negative group (P<0.001). The incidence rates of incomplete enhancing "capsule" , non-smooth tumor margin, arterial peritumoral enhancement, mosaic architecture and peritumoral hypointensity on hepatobiliary phase (HBP) in pMVI positive group were significantly higher than those of negative group (all P<0.05). Multivariate logistic regression analysis showed that tumor margin, arterial peritumoral enhancement, peritumoral hypointensity on HBP and ADC value were independently associated with pMVI. ROC analysis showed that the area under curve, sensitivity and specificity of pMVI predicted by combined parameters were 0.830, 76.5% and 81.5%, respectively. The median RFS of mrMVI positive group was 23.6 months, significantly lower than 38.2 months of mrEMVI negative group (P=0.004). Conclusion: Tumor margin, arterial peritumoral enhancement, peritumoral hypointensity on HBP and ADC value are independent predictors of pMVI in HCC, and mrMVI is related with RFS.

[Merkel cell carcinoma: a clinicopathological study of 10 cases].

Objective: To investigate the clinicopathological features, differential diagnosis and prognosis of Merkel cell carcinoma (MCC). Methods: The clinical and pathological data of 10 patients with MCC were collected at the 940th Hospital of PLA. The histological characteristics were examined. Immunohistochemical EnVision method was used to detect thyroid transcription factor-1 (TTF1), broad-spectrum cytokeratin (CKpan), CK20, S-100, Ki-67, CD56, chromogranin A, synaptophysin and other markers in the 10 cases. Results: Intradermal MCC of the skin showed a nested, cord-like, cribriform distribution, polygonal cells, uniform size, and lack of cytoplasm. Tumor cell nuclei were large and round, with clear nuclear membranes, fine and scattered chromatin, absence of nucleoli, and mitotic figures of 10 per 50 high power fields. Among them, one patient had sarcoma and squamous cell carcinoma in situ, one patient had squamous cell carcinoma in situ, and one patient had unique cell morphology. Immunohistochemical staining showed that all cancer cells expressed CKpan, synaptophysin and CD56. There were seven cases with perinuclear dot-like positivity of CK20. Six MCCs expressed chromogranin A to varying degrees, while 2 MCCs were weakly positive for p63. The nuclear positive index in the Ki-67 hotspot area was 60%. Conclusion: The histology of MCC varies. Rendering a correct diagnosis of MCC requires adequate sampling, close correlation with clinical history and rational use of immunohistochemical staining. The treatment requires standardized surgery, postoperative radiotherapy and multimodal chemotherapy. Immunotherapy may replace the traditional treatment in the future.

[Performance of human papillomavirus typing test in cervical precancer lesions and cervical cancer screening].

Objective: To evaluate the performance of Hybribio human papillomavirus (HPV) typing test kit for high risk HPV-DNA typing detection in screening of cervical precancer lesions. Methods: A total of 9 914 women were recruited in Henan, Shanxi, and Guangdong provinces from June to July 2017. All women underwent HPV DNA test. The women who diagnosed as HPV positive and cytological examination ≥ atypical squamous cells of undetermined significance (ASCUS) or HPV negative and cytological examination≥low-grade squamous intraepithelial lesions (LSIL) underwent colposcopy biopsy and pathological examination. Using the pathological diagnosis as the gold standard, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and 95% confidence interval (CI) of high-risk HPV and HPV16/18 tests were calculated. Results: The mean age of 9 914 subjects was (45.0±9.3) years old. Among them, 1 302 subjects were detected as high risk HPV positive, including 211 of HPV16 positive and 64 of HPV18 positive. According to the pathological gold standard of cervical intraepithelial neoplasia grade 2 (CIN2) or worse, the sensitivity and specificity of high risk-HPV and HPV 16/18 for triaging ASCUS women were 90.6% (95%CI: 75.8%-96.8%) and 78.0% (95%CI: 74.5%-81.2%) as well as 56.3% (95%CI: 39.3%-71.8%) and 95.7% (95%CI: 93.8%-97.1%), respectively. The sensitivity and specificity of high risk-HPV and HPV 16/18 for cervical precancer lesions screening were 95.1% (95%CI: 88.1%-98.1%) and 87.6% (95%CI: 86.9%-88.2%) as well as 65.9% (95%CI: 55.1%-75.2%) and 97.8% (95%CI: 97.5%-98.1%), respectively. Conclusions: The Hybribio HPV test kit has a relative high sensitivity and specificity for cervical precancer lesions screening and ASCUS triaging. It is reliable for HPV DNA detection and cervical cancer screening.

[A method for constructing three-dimensional face symmetry reference plane based on weighted shape analysis algorithm].

OBJECTIVE: To establish a novel method based on three-dimensional (3D) shape analysis and weighted Procrustes analysis (WPA) algorithm to construct a 3D facial symmetry reference plane (SRP), automatically assigning weight to facial anatomical landmarks. The WPA algorithm suitability for commonly observed clinical cases of mandibular deviation were analysed and evaluated. METHODS: Thirty patients with mandibular deviation were recruited for this study. The 3D facial SRPs were extracted independently based on original-mirror alignment method. Thirty-two anatomical landmarks were selected from the overall region by three times to obtain the mean coordinate. The SRP of experimental groups 1 and 2 were using the standard Procrustes analysis (PA) algorithm and WPA algorithm, respectively. A reference plane defined by experts based on regional iterative closest point (ICP) algorithm, served as the ground truth. Three experts manually selecting facial regions with good symmetry for original model, and common region was included in the study. The angle error values between the SRP of WPA algorithm in the experimental group 1 and the truth plane were evaluated in this study, and the SRP of PA algorithm of experimental group 2 was calculated in the same way. Statistics and measurement analysis were used to comprehensively evaluate the clinical suitability of the WPA algorithm to calculate the SRP. A paired t-test analysis (two-tailed) was conducted to compare the angles. RESULTS: The average angle error between the SRP of WPA algorithm and the ground truth was 1.53°±0.84°, which was smaller than that between the SRP of PA and the ground truth (2.06°±0.86°). There were significant differences in the angle errors among the groups (P < 0.05). For the patients with severe mandibular deviation that the distance between pogonion and facial midline greater than 12 mm, the average angle error of the WPA algorithm was 0.86° smaller than that of the PA algorithm. CONCLUSION: The WPA algorithm, based on weighted shape analysis, can provide a more adaptable SRP than the standard PA algorithm when applied to mandibular deviation patients and preliminarily simulate the diagnosis strategies of clinical experts.

[The differential diagnosis for novel coronavirus pneumonia and similar lung diseases in general hospitals].

Novel coronavirus pneumonia was a novel coronavirus infection that has dominated pulmonary infection since December 2019. The main manifestations were fever, dry cough, shortness of breath, normal or leukopenia in peripheral blood and changes in chest CT and in severe cases, multiple organ failure might occur. The National Health Commission, PRC has revised the consensus on diagnosis and treatment seven times in a short period of time, indicating the growing understanding of the disease. Patients with novel coronavirus pneumonia usually had history of travelling or living in the epidemic area including Wuhan within 14 days before onset, or have been exposed to patients who had fever or respiratory symptoms from the epidemic area, or had clustering diseases. However, novel coronavirus pneumonia was becoming more and more blurred after vanishing epidemic. The diagnosis and differential diagnosis of novel coronavirus pneumonia were challenges not only because of large number of tourists increasing dramatically after the relieving of epidemic, but also patients with other diseases from different areas to search for medical care. In this article, the clinical and chest imaging features of the novel coronavirus pneumonia were reviewed and compared with other infections and non-infectious diffuse pulmonary diseases. We try to find the similarities and differences among them, and to identify clues to the diagnosis of novel coronavirus pneumonia, so as to ensure accurate diagnosis and treatment.

InAs/GaAs quantum dot semiconductor saturable absorber for controllable dual-wavelength passively Q-switched fiber laser.

We experimentally demonstrate the first use of 1550-nm InAs/GaAs quantum dot semiconductor saturable absorber mirror (QD-SESAM) in the dual-wavelength passively Q-switched (QS) erbium doped fiber (EDF) laser. The dual-wavelength QS lasing was obtained at a pump threshold of 180 mW with the average output power of 2.2 mW and the spacing between the two lasing wavelengths is 14 nm. A large absorption ranging from 1520 to 1590 nm has been realized when no substrate rotation was employed during the molecular beam epitaxy growth of the QD-SESAM indicating the potential to generate a 60 nm spacing of the dual-wavelength QS lasing peaks by changing the positions in the QD-SESAM and replacing EDF by co-doped fiber as gain medium. These results have provided a new opportunity towards achieving the stable and wide wavelength-tunable dual-modes fiber lasers.

Antibacterial activity against Ralstonia solanacearum of the lipopeptides secreted from the Bacillus amyloliquefaciens strain FJAT-2349.

AIMS: The aims of this study were to identify the structure of antibacterial lipopeptide (LP) produced by Bacillus amyloliquefaciens strain FJAT-2349, to analyse the effects of the culture medium and temperature on LP production and to assess the biocontrol efficiency of the LPs against tomato bacterial wilt. METHODS AND RESULTS: Lipopeptides were extracted by acid precipitation and resolved in methanol and their structure was identified through LC-QTOF-MS/MS method. The antibacterial activities of the LPs were evaluated through inhibition zone experiments. The biocontrol efficiency of the LPs against tomato bacterial wilt was examined by a pot test. The LPs were composed of iturin (C14 -C17 iturin A), fengycin (C14 /C16 fengycin A, C14 fengycin B2 , C16 fengycin A2 /B2 , C16 -C17 fengycin B, C15 fengycin A derivatives and C15 fengycin B derivatives) and surfactin (C12 -C16 surfactin A). Moreover, the composition of the LPs was significantly influenced by the culture medium and temperature; the contents of iturin, fengycin and surfactin varied within the range from 0·41-5·89, 4·54-181·67 and 2·05-19·65 mg l-1 in the different culture media and from 0·39-11·04, 1·45-215·14 and 7·79-24·43 mg l-1 under different culture temperatures respectively. The results indicated that the contents of the LP mixture, fengycin and surfactin secreted from FJAT-2349 all decreased along with an increasing culture temperature. The fermentation supernatants and LP extracts had the strongest inhibition activities of Ralstonia solanacearum when strain FJAT-2349 was incubated at 25°C using potato dextrose broth as the culture medium among all the assayed culture conditions. The purified fengycin was found to be the active antibacterial compound against R. solanacearum, but the purified surfactin was not. The pot experiments demonstrated that the LPs secreted from the strain FJAT-2349 could effectively control the tomato bacterial wilt with a biocontrol efficiency of 97·6%. CONCLUSIONS: The LPs secreted from strain FJAT-2349 could serve as potential biocontrol agents against tomato bacterial wilt. SIGNIFICANCE AND IMPACT OF THE STUDY: The LPs exhibited good potential applications in the biocontrol of tomato bacterial wilt.

[Predictive value of quantitative dynamic contrast-enhanced magnetic resonance imaging for the efficacy of neoadjuvant chemotherapy in locally advanced gastric cancer].

Objective: To investigate the predictive value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) quantitative parameters for the efficacy of neoadjuvant chemotherapy in locally advanced gastric cancer. Methods: Sixty-five patients with locally advanced gastric cancer (LAGC) confirmed by gastroscopy and received neoadjuvant chemotherapy (NCT) were enrolled in this study. Quantitative DCE-MRI was performed before NCT, and the quantitative parameters were measured, including volume transfer constant (K(trans)), rate constant (K(ep)), volume fraction of extravascular extracellular space (V(e)) and volume fraction of plasma (V(p)). After NCT, all patients received radical gastrectomy. According to postoperative pathological tumor regression grade, patients were divided into response group and non-response group, and the differences of DCE quantitative parameters between the two groups were compared. ROC curve was utilized to analyze the predictive efficacy of DCE quantitative parameters for NCT response of LAGC, and multivariate logistic regression analysis was performed to analyze the predictive efficacy of combined parameters. Results: Thirty-seven patients were in response group and 28 patients were in non-response group. The pretreatment K(trans) in the response group were [0.216 min(-1) (0.130 min(-1), 0.252 min(-1))], significantly higher than [0.091 min(-1) (0.069 min(-1), 0.146 min(-1))] of non-response group (P<0.001), and V(e) in the response group were [0.354(0.228, 0.463)], significantly higher than [0.200(0.177, 0.253)]of non-response group (P<0.001). ROC analysis showed the AUCS of K(trans) and V(e) in predicting NCT efficacy were 0.881 and 0.756, respectively. Multiple logistic regression analysis showed that the combination of the two parameters could improve the AUC to 0.921, with the sensitivity and specificity of 86.5% and 89.3%, respectively. Conclusion: DCE-MRI quantitative parameters could help to predict the NCT response of LAGC, and the combination of parameters could improve the predictive efficacy.

[Experience of 14 cases using hemi-semilaminectomy microsurgery treating by spinal dural arteriovenous fistula].

Objective: To explore the efficacy and feasibility of the hemi-semilaminectomy microsurgical operation treatment of spinal dural arteriovenous fistula (SDAVF). Methods: The clinical data of 32 patients with SDAVF were analyzed retrospectively. Before operation all patients were diagnosed by spinal MRI and spinal angiography, 14 patients were treated by hemi-semilaminectomy approach and other 18 patients were by traditional laminectomy approach. All the data were analyzed by T test and P<0.05 was considered to have significant difference. Results: The nidus of SDAVF located on thoracic segments in 18 cases, lumbar segments in 12 cases, and cervical segment in 2 cases, which was fed by single artery. The hemi-semilaminectomy microsurgical operation showed shorter operation time, less bleeding, less hospitalization time and cost. All the patients followed-up for 6 months-2 years. Symptoms of all the patients were improved compared with those before surgery. Conclusions: On the premise of spinal angiography accurately positioning the location of fistula, the hemi-semi-laminectomy approach microsurgery clipping operation is safe and feasible, and the operation has fewer traumas, also helps to maintain the stability of spine.

[Influence of carrying system on human gait and fatigue].

Objective: To investigate the influence of different variable combinations of the carrying system on gait and muscle fatigue during weight-bearing walking on both shoulders and back, and to optimize daily carrying experience. Methods: From September to December, 2018, 6 male college students were selected as subjects; the electromyographic signal of the anterior tibial muscle and plantar pressure were measured during weight-bearing walking under six different variable combinations of the carrying system (with the three variables of gravity center, single or double shoulders, and waist cushion), and a subjective evaluation test was performed for the degree of fatigue. The electromyographic data and plantar pressure data were processed and compared to evaluate behavior and fatigue. Results: Different variable combinations of the carrying system had significant influence on the degree of fatigue and gait (P<0.05). Both subjective and objective analyses found that the carrying system with different heights of gravity center and single-or double-shoulder carrying mode had great influence on human fatigue and walking gait, while the hardness of waist cushion had little influence. Compared with the other groups, the group with a high gravity center, a double-shoulder carrying mode, and a soft waist cushion had a significantly smaller slope of average electromyographic amplitude, a significantly larger slope of median frequency, and a significantly lower degree of plantar pressure curve disorder. Conclusion: The carrying system with a relatively high gravity center, a double-shoulder carrying mode, and a soft waist cushion can significantly relieve fatigue, with low influence on walking gait.

Efficient construction of bioactive trans-5A5B6C spirolactones via bicyclo[4.3.0] α-hydroxy ketones.

An efficient, convenient short synthetic procedure for the synthesis of the intricate 5A5B6C-ring fusion topologies of tricyclic spiranoid ß-hydroxybutyrolactones through lactonization of the key intermediate trans-α-hydroxyindenones with malonates is described. All the compounds synthesized exhibited environmentally benign characteristics, moderate fungicidal, nematocidal, and anti-TMV activities.