[Influencing factors and antenatal assessment of the vaginal birth after cesarean section]

Objective: To explore the influencing factors of the vaginal birth after cesarean section (VBAC), and establish a model for predicting the risk of trial of the trial of labor after cesarean section (TOLAC). Methods: From January 2016 to December 2018, total 694 pregnant women who underwent TOLAC in Northwest Women's and Children's Hospital were retrospectively analyzed. Those cases were divided into two groups according to the mode of delivery: the VBAC group and the failed TOLAC group. At the same time, 700 cases in the elective repeat cesarean section (ERCS) group were randomly selected as control group. The influencing factors of VBAC were analyzed by univariate and multivariate logistic regression, and the pregnancy outcomes between the three groups were compared. Results: (1) The VBAC rate was 76.1% (528/694) and 166 women underwent the failed TOLAC (23.9%, 166/694). (2) Univariate analysis found that, the pre-pregnancy body mass index (BMI) [(22.0±3.0), (23.3±2.7) kg/m(2)], the previous vaginal delivery history [10.4%(55/528), 3.6%(6/166)], the cervical score (5.2±1.9,4.3±1.6) and the neonatal birth weight [(3 315±468), (3 484±274) g] of the VBAC group were significantly different from the failed TOLAC group (P<0.05). (3) The comparison of pregnancy outcomes: the neonatal birth weight was (3 315±468) g, and the intrapartum hemorrhage volume was (255±121) ml in the VBAC group, which were significantly lower than those in the failed TOLAC group [intrapartum hemorrhage (325±173) ml] and the ERCS group [(3 572±344) g, (281±125) ml], there were statistically significant differences in the comparison among the three groups (all P<0.05). Two cases of bladder injury occurred during cesarean section in the TOLAC failure group (1.2%,2/166). The rates of the blood transfusion, puerperal infection, 5-minute Apgar score and neonatal ICU admission among the three groups were no statistically significantly different (all P>0.05). There was no maternal or perinatal death. (4) Multivariate logistic regression analysis showed that the delivery age of pregnant women (OR=0.92, 95%CI: 0.87-0.98), pre-pregnancy BMI (OR=0.92, 95%CI:0.86-0.98), vaginal delivery history (OR=3.31, 95%CI: 1.35-8.01), cervical score (OR=1.29, 95%CI: 1.13-1.42) and the birth weight of the neonates <3 300 g (OR=3.15, 95%CI: 2.02-4.90) were independent influencing factors for VBAC. The area under curve of the receiver operating characteristic curve was 0.74. Conclusions: The influencing factors of VBAC are delivery age, pre-pregnancy BMI, vaginal delivery history, cervical score and neonatal birth weight <3 300 g. The adequate individualized management and assessment of the TOLAC may be helpful to improve the VBAC rate.

ROC study and SUV threshold using quantitative multi-modal SPECT for bone imaging

Background

We investigated the clinical performance of a quantitative multi-modal SPECT/CT reconstruction platform for yielding radioactivity concentrations of bone imaging with ^99mTc-methylene diphosphonate (MDP) or ^99mTc-dicarboxypropane diphosphonate (DPD). The novel reconstruction incorporates CT-derived tissue information while preserving the delineation of tissue boundaries. We assessed image-based reader concordance and confidence, and determined lesion classification and SUV thresholds from ROC analysis.

Methods

Seventy-two cancer patients were scanned at three US and two German clinical sites, each contributing two experienced board-certified nuclear medicine physicians as readers. We compared four variants of the reconstructed data resulting from the Flash3D (F3D) and the xSPECT Bone™ (xB) iterative reconstruction methods and presented images to the readers with and without a fused CT, resulting in four combinations. We used an all-or-none approach for inclusion, compiling results only when a reader completed all reads in a subset. After the final read, we conducted a “surrogate truth” reading, presenting all data to each reader. For any remaining discordant lesions, we conducted a consensus read. We next undertook ROC analysis to determine SUV thresholds for differentiating benign and lesional uptake.

Results

On a five-point rating scale of image quality, xB was deemed better by almost two points in resolution and one point better in overall acceptance compared to F3D. The absolute agreement of the rendered decision between the nine readers was significantly higher with CT information either inside the reconstruction (xB, xBCT) or simply through image fusion (F3DCT): 0.70 (xBCT), 0.67 (F3DCT), 0.64 (xB), and 0.46 (F3D). The confidence level to characterize the lesion was significantly higher (3.03x w/o CT, 1.32x w/CT) for xB than for F3D. There was high correlation between xB and F3D scores for lesion detection and classification, but lesion detection confidence was 41% higher w/o CT, and 21% higher w/CT for xB compared to F3D. Without CT, xB had 6.6% higher sensitivity, 7.1% higher specificity, and 6.9% greater AUC compared to F3D, and similarly with CT-fusion. The overall SUV-criterion (SUV_c) of xB (12) exceeded that for xSPECT Quant™ (xQ; 9), an approach not using the tissue delineation of xB. SUV critical numbers depended on lesion volume and location. For non-joint lesions > 6 ml, the AUC for xQ and xB was 94%, with SUV_c > 9.28 (xQ) or > 9.68 (xB); for non-joint lesions ≤ 6 ml, AUCs were 81% (xQ) and 88% (xB), and SUV_c > 8.2 (xQ) or > 9.1 (xB). For joint lesions, the AUC was 80% (xQ) and 83% (xB), with SUV_c > 8.61 (xQ) or > 13.4 (xB).

Conclusion

The incorporation of high-resolution CT-based tissue delineation in SPECT reconstruction (xSPECT Bone) provides better resolution and detects smaller lesions (6 ml), and the CT component facilitates lesion characterization. Our approach increases confidence, concordance, and accuracy for readers with a wide range of experience. The xB method retained high reading accuracy, despite the unfamiliar image presentation, having greatest impact for smaller lesions, and better localization of foci relative to bone anatomy. The quantitative assessment yielded an SUV-threshold for sensitively distinguishing benign and malignant lesions. Ongoing efforts shall establish clinically usable protocols and SUV thresholds for decision-making based on quantitative SPECT.

Factors Influencing Families' Decision-Making for Organ Donation in Hunan Province, China

BACKGROUND

In 2010, the Chinese government started a pilot project of donation after Chinese citizens' death. Seeking the consent of the families of potential donors is an important task in the organ donation process.

OBJECTIVE

We aimed to explore the factors that influence the families' decision-making for organ donation.

METHODS

We performed a content analysis of 30 semistructured in-depth interviews with immediate family members who made the decision for an organ donation. The interviewees were asked questions such as how the decision to donate was made, what factors influenced the decision, and whether the decision was rejected by relatives and friends.

RESULTS

The interviewees were the donors' parent (15; 50%), spouse (9; 30%), brother (3; 10%) or son (3; 10%), including 18 men and 12 women, with a mean age of 41.6 (standard deviation, 10.7) years; rural households accounted for 83.3%. Through analyzing the interview notes, 17 factors ware mentioned by interviewees, and 3 types of decision-making in organ donors' families were obtained. Then, the factors affecting the decisions of the donor families were classified into 3 categories and 11 subcategories.

CONCLUSIONS

Factors influencing the families' decision-making for organ donation were analyzed preliminarily in this study.

A puzzling pregnancy epulis with aggressive bone loss mimicking malignant neoplasm: A case report

Epulis is a benign tumor, rarely involves aggressive alveolar bone resorption. This study reported a rare case of rapid growth of pregnancy epulis with extensive alveolar bone destruction and the management of this case. A 24-year old pregnant woman at 35 weeks and 1 day of gestation presented a large asymptomatic nodular mass with severe teeth loosening at the anterior mandibular region for 4 weeks. Radiographic examination showed extensive alveolar bone resorption around the affected teeth to the apical area. After delivery, the patient received an extended resection under general anesthesia. The final histopathological analysis revealed the diagnosis of epulis. In conclusion, the rapid growth of epulis during pregnancy mimicking malignant neoplasm with aggressive alveolar bone destruction was rare and puzzling. In such cases, the histopathological and immunohistochemical examinations are the only effective method to reach the correct diagnosis and clinician should proceed with high precaution.

Analysis of Forensic Sciences Literature in SCIE from 2008 to 2017

OBJECTIVES

To analyze the literature on forensic sciences indexed in Science Citation Index Expanded （SCIE） in recent 10 years, and to understand the research status, characteristics and trends in the field of forensic sciences.

METHODS

Literature on forensic sciences from 2008 to 2017 in Web of Science （WoS） was retrieved. The documents number and geographical distribution, document types, source titles, organizations, research areas, authors, funding agencies, and the high cited articles were detected. The impact factors （IF） of journals were retrieved in Journal Citation Reports （JCR）. The data were analyzed with descriptive statistics.

RESULTS

From 2008 to 2017, there were 21 001 documents on forensic sciences in SCIE. The main document type was articles, with English as the major language. With regards to research areas, pathology has the largest number of papers worldwide, and genetics and heredity has the largest number of publications in mainland China. Among the 18 journals where the documents was published, Forensic Science International ranks the first on publication count, and Forensic Science International Genetics has the highest IF （5.637） in the JCR 2017. In 2017, the number of papers from mainland China increased by 48.50% compared with 2016, which was higher than the global increase （32.63%） and the top-5 countries in terms of number of publications （the US, Germany, the UK, Australia, Italy）. The average document count per organization is 1.98 worldwide and 1.17 in mainland China, respectively. The publication number per author is 0.53 worldwide and 0.36 in mainland China, respectively. Around 28.17% of the publications were funded, with National Natural Science Foundation of China （NSFC） as the Top 1 funding agency （192 papers）. Among the documents with citations, the most cited publication has been cited for 366 times.

CONCLUSIONS

The yearly numbers of publications on forensic sciences are increasing during recent 10 years. Focusing on the mainland China, there would be more high-quality papers with the steady funding of NSFC.

Classification of water contamination developed by 2-D Gabor wavelet analysis and support vector machine based on fluorescence spectroscopy

The identification of the specific categories of pollutants in the urban water supply system is necessary. Traditional detection methods are based mainly on common water quality indicators. However, inspecting these water quality indicators is made difficult by issues such as long analysis time, insufficient sensitivity, need for reagents, and generation of waste liquid. These problems hinder high-frequency water detection and monitoring. In this study, three-dimensional (3D) fluorescence spectroscopy is adopted as a monitoring method for water quality. An identification method based on two-dimensional (2D) Gabor wavelets and support vector machine (SVM) multi-classification is also proposed. The Delaunay triangulation method for interpolation is used to pre-process 3D fluorescence spectra and thereby eliminate Rayleigh scattering and Raman scattering. A 2D Gabor wavelet function generated by filters of different scales and rotation angles is proposed to extract the features of the spectra. The block statistics method, based on Gabor feature description, is employed to enhance the efficiency in describing spectra features. Then, multiple SVM classifiers are used in pollutant classification and recognition. By comparing the proposed method with principal component analysis, which is a commonly used feature extraction method, this study finds that the application of 2D Gabor wavelets and block statistics can effectively describe the characteristics of 3D fluorescence spectra. Moreover, 2D Gabor wavelets achieve high classification accuracy, especially for substances with closely positioned or overlapping characteristic peaks.

Infrared Spectral Characteristics of Electrical Injuries on Swine Skin Caused by Different Voltages Based on Machine Learning Algorithms

OBJECTIVES

To explore infrared spectrum characteristics of different voltages induced electrical injuries on swine skin by using Fourier transform infrared-microspectroscopy （FTIR-MSP） combined with machine learning algorithms, thus to provide a reference to the identification of electrical skin injuries caused by different voltages.

METHODS

Electrical skin injury model was established on swines. The skin was exposed to 110 V, 220 V and 380 V electric shock for 30 s and then samples were took, with normal skin tissues around the injuries as the control. Combined with the results of continuous section HE staining, the FTIR-MSP spectral data of the corresponding skin tissues were acquired. With the combination of machine learning algorithms such as principal component analysis （PCA） and partial least squares-discriminant analysis （PLS-DA）, different spectral bands were selected （full band 4 000-1 000 cm^-1 and sub-bands 4 000-3 600 cm^-1, 3 600-2 800 cm^-1, 2 800-1 800 cm^-1, and 1 800-1 000 cm^-1）, and various pretreatment methods were used such as orthogonal signal correction （OSC）, standard normal variables （SNV）, multivariate scatter correction （MSC）, normalization, and smoothing. Thus, the model was optimized, and the classification effects were compared.

RESULTS

Compared with simple spectrum analysis, PCA seemed to be better at distinguishing electrical shock groups from the control, but was not able to distinguish different voltages induced groups. PLS-DA based on the 3 600-2 800 cm^-1 band was used to identify the different voltages induced skin injuries. The OSC could further optimize the robustness of the 3 600-2 800 cm^-1 band model.

CONCLUSIONS

It is feasible to identify electrical skin injuries caused by different voltages by using FTIR-MSP technique along with machine learning algorithms.

[Prevalence and risk factors of diabetic retinopathy in hospital patients]

Objective: To analyze the prevalence and risk factors of diabetic retinopathy (DR) in ophthalmic patients. Methods: A cross-sectional study was performed. Diabetic patients who were admitted to Department of Ophthalmology, Traditional Chinese Medicine Hospital of Muping between October 2012 and June 2013 were included. General information and medical history were obtained from each subject by questionaires. Laboratory and detailed ophthalmic examinations were performed during the study. DR was diagnosed and graded by mydriatic fundus photography. Prevalence of DR was calculated and logistic regression was used to analyze the relationship between DR and various factors. Results: A total of 676 diabetic patients were included, and 455 of them presented with DR at a morbidity rate of 67.31%. Among DR patients, the number of mild, moderate, severe non-proliferative diabetic retinopathy (NPDR) patients and proliferative diabetic retinopathy (PDR) patients were 211 (46.37%), 167 (36.70%), 57 (12.53%) and 20 (4.40%), respectively. There was no significant difference in the prevalence of DR among different age groups (χ(2)=6.527, P=0.089). However, there was a significant difference between different disease duration groups (χ(2)=39.401, P<0.001), as well as between insulin therapy group and non-insulin therapy group (χ(2)=7.378, P=0.007). The multivariate logistic regression analysis demonstrated the independent risk factors for DR occurrence were hemoglobin A1c (HbA1c) (OR=1.131, 95%CI: 1.022-1.252, P=0.011) and duration of diabetes (OR=1.077, 95%CI: 1.046-1.108, P<0.001). Conclusions: The prevalence of DR in ophthalmic patients was associated with duration of diabetes, HbA1c, obesity, smoke, nephropaty and insulin therapy. Increased HbA1c level and longer duration of diabetes were independent risk factors for DR in diabetic patients.

Convective-Dispersion Modeling in 3D Contrast-Ultrasound Imaging for the Localization of Prostate Cancer

Despite being the solid tumor with the highest incidence in western men, prostate cancer (PCa) still lacks reliable imaging solutions that can overcome the need for systematic biopsies. Dynamic contrast-enhanced ultrasound imaging (DCE-US) allows us to quantitatively characterize the vascular bed in the prostate, due to its ability to visualize an intravenously administered bolus of contrast agents. Previous research has demonstrated that DCE-US parameters related to the vascular architecture are useful markers for the localization of PCa lesions. In this paper, we propose a novel method to assess the convective dispersion (D) and velocity (v) of the contrast bolus spreading through the prostate from three-dimensional (3D) DCE-US recordings. By assuming that D and v are locally constant, we solve the convective-dispersion equation by minimizing the corresponding regularized least-squares problem. 3D multiparametric maps of D and v were compared with 3D histopathology retrieved from the radical prostatectomy specimens of six patients. With a pixel-wise area under the receiver operating characteristic curve of 0.72 and 0.80, respectively, the method shows diagnostic value for the localization of PCa.

Current Research and Prospects on Postmortem Interval Estimation

The researches on postmortem interval （PMI） estimation are very important and meaningful in forensic science. PMI estimation is also an important issue that must be solved in practice of forensic pathology. There are many defects existing in traditional methods for PMI estimation, so it is imperative to introduce new pathways. With the emergence of various new technologies, the researches on PMI estimation have a tendency from simple to complex with a growth of data. The present review firstly summarizes a series of methods used for PMI estimation, and then gives an outlook for the application of artificial intelligence algorithms in this field.

[Effects of Temperature on FTIR Spectral Characteristics of Renal Tissue in Rats after Death]

OBJECTIVES

To analyse the Fourier transform infrared （FTIR） spectral data of renal tissue at different temperatures in rats after death, and to explore the effects of temperature on the FTIR spectral characteristics of renal tissue.

METHODS

The rats were sacrificed by cervical dislocation and placed at 4 ℃, 20 ℃ and 30 ℃. The FTIR spectral data of renal tissue were collected at different time points and analysed by data mining method.

RESULTS

The principal component analysis （PCA） results showed that there were significant trends of clustering in the samples of partial time point at 4 ℃, 20 ℃ and 30 ℃. Partial least square （PLS） regression models were established with the spectral data at three temperature groups. The performance of PLS regression models in 20 ℃ and 30 ℃ groups were more superior than that in 4 ℃ group, and the stability of the model in 20 ℃ group was better than that in 30 ℃ group.

CONCLUSIONS

There are differences in the FTIR spectral characteristics of renal tissue of rats after death at different temperatures. Temperature has a major impact on the performance of FTIR spectral PLS regression model. Therefore, in order to improve the accuracy of postmortem interval estimation, the effects of temperature on the model should be considered in the related study by spectral method.

[Epidemiology related to soil-borne nematode disease in Danzhou city, Hainan province]

Objective: To understand the prevalence, trend and related factors on soil-borne nematode in Danzhou city to provide information for prevention and control of the disease. Methods: According to the guidelines set by the National National soil-borne nematode technical solutions, one village was randomly chosen from every township as the monitoring location, in the east, west, south and north parts of Danzhou city. A total of 200 residents aged 3 years and over were randomly selected in each monitoring site, with modified Kato thick smear and Cellophane tape anal swab used for microscopy. Results: In this survey, we retrospectively analyzed the rates on soil borne nematode infection in five monitoring locations of Danzhou city and the results showed that the overall positive rates of infection was 19.5% (195/1 000). Comparing with the previous surveys, rates on soil-borne parasites infection were decreasing. The main types of soil-borne nematode infection appeared as roundworm, whipworm, hookworm and pinworm in Danzhou city, with rate of hookworm-egg infection ranking the highest (42.5%, 85/200) in Dacheng. The infection rate was seen significantly higher in females than males. People aged over 60 and between 3-10, had a higher rates of infection. Rate on multiple infections reached 16.9%, including 5 triple infection cases. Conclusion: Rates of infection on soil-borne nematodes in Danzhou city showed a decreasing trend from 2013 to 2016 with hookworm and whipworm as the major ones.

Laser-Induced Skyrmion Writing and Erasing in an Ultrafast Cryo-Lorentz Transmission Electron Microscope

We demonstrate that light-induced heat pulses of different duration and energy can write Skyrmions in a broad range of temperatures and magnetic field in FeGe. Using a combination of camera-rate and pump-probe cryo-Lorentz transmission electron microscopy, we directly resolve the spatiotemporal evolution of the magnetization ensuing optical excitation. The Skyrmion lattice was found to maintain its structural properties during the laser-induced demagnetization, and its recovery to the initial state happened in the sub-μs to μs range, depending on the cooling rate of the system.

Abstract P2-02-11: Not presented

This abstract was not presented at the symposium.

Abstract P2-05-12: Not presented

This abstract was not presented at the symposium.