Progress on the application of capsular tension ring in high myopia combined with cataract / 国际眼科杂志(Guoji Yanke Zazhi)

In recent years, the incidence of high myopia complicated with cataract shows a gradual upward trend. Due to the special anatomical structure and lesion nature of high myopia, the difficulty and various complications of such patients are much higher than those of ordinary cataract surgery. With the continuous advancement of design and materials, the indications for capsular tension ring(CTR)have gradually expanded. Especially for patients with high myopia,it can maintain the stability of intraocular lens position, assist the relaxation of the suspensory ligament, inhibit the migration and proliferation of residual lens epithelial cells after surgery, improve the visual quality of patients and reduce the incidence of retinal detachment. This paper reviewed the history of CTR, its clinical application, and the effect of CTR on high myopia complicated with cataract.

Comparison among Four Deep Learning Image Classification Algorithms in AI-based Diatom Test / 法医学杂志

OBJECTIVES@#To select four algorithms with relatively balanced complexity and accuracy among deep learning image classification algorithms for automatic diatom recognition, and to explore the most suitable classification algorithm for diatom recognition to provide data reference for automatic diatom testing research in forensic medicine.@*METHODS@#The "diatom" and "background" small sample size data set (20 000 images) of digestive fluid smear of corpse lung tissue in water were built to train, validate and test four convolutional neural network (CNN) models, including VGG16, ResNet50, InceptionV3 and Inception-ResNet-V2. The receiver operating characteristic curve (ROC) of subjects and confusion matrixes were drawn, recall rate, precision rate, specificity, accuracy rate and F1 score were calculated, and the performance of each model was systematically evaluated.@*RESULTS@#The InceptionV3 model achieved much better results than the other three models with a balanced recall rate of 89.80%, a precision rate of 92.58%. The VGG16 and Inception-ResNet-V2 had similar diatom recognition performance. Although the performance of diatom recall and precision detection could not be balanced, the recognition ability was acceptable. ResNet50 had the lowest diatom recognition performance, with a recall rate of 55.35%. In terms of feature extraction, the four models all extracted the features of diatom and background and mainly focused on diatom region as the main identification basis.@*CONCLUSIONS@#Including the Inception-dependent model, which has stronger directivity and targeting in feature extraction of diatom. The InceptionV3 achieved the best performance on diatom identification and feature extraction compared to the other three models. The InceptionV3 is more suitable for daily forensic diatom examination.

Research Progress of Automatic Diatom Test by Artificial Intelligence / 法医学杂志

Diatom test is the main laboratory test method in the diagnosis of drowning in forensic medicine. It plays an important role in differentiating the antemortem drowning from the postmortem drowning and inferring drowning site. Artificial intelligence (AI) automatic diatom test is a technological innovation in forensic drowning diagnosis which is based on morphological characteristics of diatom, the application of AI algorithm to automatic identification and classification of diatom in tissues and organs. This paper discusses the morphological diatom test methods and reviews the research progress of automatic diatom recognition and classification involving AI algorithms. AI deep learning algorithm can assist diatom testing to obtain objective, accurate, and efficient qualitative and quantitative analysis results, which is expected to become a new direction of diatom testing research in the drowning of forensic medicine in the future.

Effects of Linc00460 on Aerobic Glycolysis in Breast Cancer Cells via Sponge Adsorption of miR-320a / 肿瘤防治研究

Objective To explore the effect of Linc00460 on the aerobic glycolysis of breast cancer (BC) cells through sponge adsorption of miR-320a. Methods The qRT-PCR method was used to detect Linc00460 and miR-320a expression levels in normal breast epithelial cell line MCF-10A and five BC cell lines. The effect of interfering Linc00460 on miR-320a expression was detected by qRT-PCR. The double luciferase reporter gene experiment was used to analyze the targeting relationship between miR-320a and Linc00460. In addition, the si-Linc00460 and miR-320a inhibitor were co-transfected into MDA-MB-231 cells, and the expression level of miR-320a in the cells was detected by qRT-PCR; cell proliferation ability was measured by the MTT method; glucose uptake rate was detected by 2-NBDG method; the content of lactic acid in the cell supernatant was detected by colorimetric method; the key enzymes of glycolysis was detected by the enzyme activity kit; and the expression levels of the key proteins in the glycolysis pathway were detected by Western blot. Results Linc00460 was highly expressed in five BC cell lines, while miR-320a was lowly expressed as compared with MCF-10A cells. The expression of miR-320a in MDA-MB-231 cells significantly increased after interfering with Linc00460. The double luciferase reporter gene experiment confirmed that miR-320a and Linc00460 could target binding. Interfering with the expression of Linc00460 could inhibit MDA-MB-231 cells proliferation (all P=0.000), reduce the rate of cellular glucose uptake and the content of lactic acid in the cell supernatant (all P=0.000), inhibit the activities of PFK, PK, and LDH enzymes (all P=0.000), and downregulate the protein expression levels of PFKM, GLUT1, and LDHA (all P=0.000). Meanwhile, inhibition of miR-320a could reverse the inhibitory effect of si-Linc00460 on the proliferation and glycolysis of MDA-MB-231 cells (all P=0.000 or 0.001). Conclusion Linc00460 might adsorb miR-320a, consequently leading to upregulation of PFKM expression, thereby promoting aerobic glycolysis in BC cells.

Immunogenicity and safety of a recombinant fusion protein vaccine (V-01) against coronavirus disease 2019 in healthy adults: a randomized, double-blind, placebo-controlled, phase II trial / 中华医学杂志(英文版)

BACKGROUND@#Innovative coronavirus disease 2019 (COVID-19) vaccines, with elevated global manufacturing capacity, enhanced safety and efficacy, simplified dosing regimens, and distribution that is less cold chain-dependent, are still global imperatives for tackling the ongoing pandemic. A previous phase I trial indicated that the recombinant COVID-19 vaccine (V-01), which contains a fusion protein (IFN-PADRE-RBD-Fc dimer) as its antigen, is safe and well tolerated, capable of inducing rapid and robust immune responses, and warranted further testing in additional clinical trials. Herein, we aimed to assess the immunogenicity and safety of V-01, providing rationales of appropriate dose regimen for further efficacy study.@*METHODS@#A randomized, double-blind, placebo-controlled phase II clinical trial was initiated at the Gaozhou Municipal Centre for Disease Control and Prevention (Guangdong, China) in March 2021. Both younger (n = 440; 18-59 years of age) and older (n = 440; ≥60 years of age) adult participants in this trial were sequentially recruited into two distinct groups: two-dose regimen group in which participants were randomized either to follow a 10 or 25 μg of V-01 or placebo given intramuscularly 21 days apart (allocation ratio, 3:3:1, n = 120, 120, 40 for each regimen, respectively), or one-dose regimen groups in which participants were randomized either to receive a single injection of 50 μg of V-01 or placebo (allocation ratio, 3:1, n = 120, 40, respectively). The primary immunogenicity endpoints were the geometric mean titers of neutralizing antibodies against live severe acute respiratory syndrome coronavirus 2, and specific binding antibodies to the receptor binding domain (RBD). The primary safety endpoint evaluation was the frequencies and percentages of overall adverse events (AEs) within 30 days after full immunization.@*RESULTS@#V-01 provoked substantial immune responses in the two-dose group, achieving encouragingly high titers of neutralizing antibody and anti-RBD immunoglobulin, which peaked at day 35 (161.9 [95% confidence interval [CI]: 133.3-196.7] and 149.3 [95%CI: 123.9-179.9] in 10 and 25 μg V-01 group of younger adults, respectively; 111.6 [95%CI: 89.6-139.1] and 111.1 [95%CI: 89.2-138.4] in 10 and 25 μg V-01 group of older adults, respectively), and remained high at day 49 after a day-21 second dose; these levels significantly exceed those in convalescent serum from symptomatic COVID-19 patients (53.6, 95%CI: 31.3-91.7). Our preliminary data show that V-01 is safe and well tolerated, with reactogenicity predominantly being absent or mild in severity and only one vaccine-related grade 3 or worse AE being observed within 30 days. The older adult participants demonstrated a more favorable safety profile compared with those in the younger adult group: with AEs percentages of 19.2%, 25.8%, 17.5% in older adults vs. 34.2%, 23.3%, 26.7% in younger adults at the 10, 25 μg V-01 two-dose group, and 50 μg V-01 one-dose group, respectively.@*CONCLUSIONS@#The vaccine candidate V-01 appears to be safe and immunogenic. The preliminary findings support the advancement of the two-dose, 10 μg V-01 regimen to a phase III trial for a large-scale population-based evaluation of safety and efficacy.@*TRIAL REGISTRATION@#http://www.chictr.org.cn/index.aspx (No. ChiCTR2100045107, http://www.chictr.org.cn/showproj.aspx?proj=124702).

Relationship between Stress Hyperglycemia and Catheter-related Urinary Tract Infection in Stroke Patients / 中国医学科学院学报

Objective To verify the relationship between catheter-related urinary tract infection(CAUTI)and stress hyperglycemia during catheter retention in stroke patients. Methods We used nosocomial infection monitoring system to track the status of CAUTI in stroke patients in a hospital.The study cohort was all the patients who received retention catheterization from January 2016 to March 2020.According to the nested case-control design,multivariate logistic regression analysis was performed to explore the relationship between stress hyperglycemia and CAUTI in stroke patients with indwelling catheter. Results A total of 322 cases of CAUTI and 644 cases of non-CAUTI were enrolled in this study.The length of stay in the case group was(20.68 ± 3.73)d,significantly longer than that[(13.00 ± 4.01)d]in the control group(t=29.473,P <0.001).Compared with non-stress hyperglycemia,stress hyperglycemia posed a higher risk of CAUTI in the stroke patients with indwelling catheter(OR=2.020,95% CI=1.447-2.821,P=0.000)and led to the higher incidence of CAUTI in one thousand days(P<0.001). Conclusion Stress hyperglycemia in the stroke patients with indwelling catheter can significantly increase the risk of CAUTI.

Expression and antibody preparation of recombinant truncated glycoprotein of Guertu virus / 中华微生物学和免疫学杂志

Objective:To express truncated glycoprotein (Gn, Gn1, Gn2, Gn3, Gc1 and Gc2) of Guertu virus (GTV) in Escherichia coli ( E. coli) cells, and prepare polyclonal antibodies against recombinant proteins Gn-His, Gc1-His and Gc2-His after purification. Methods:Gene fragments encoding Gn, Gn1, Gn2, Gn3, Gc1 and Gc2 of GTV DXM strain were amplified by RT-PCR, and cloned into the prokaryotic expression vector pET-32a (+ ) to construct recombinant expression plasmids. The transformed E. coli BL21(DE3) strains carrying expression plasmids were induced by IPTG to express target proteins, which were identified by SDS-PAGE. Recombinant proteins Gn-His, Gc1-His and Gc2-His were purified by nickel affinity chromatography and detected by Western blot using GTV-positive sheep serum for analysis of their antigenicity. New Zealand white rabbits were immunized with the purified recombinant proteins. The titers and specificity of serum antibodies were analyzed by ELISA. Meanwhile, eukaryotic expression vectors pcDNA3.1-Gn, pcDNA3.1-Gc1/Gc2 were constructed and transfected into mammalian Vero cells to evaluate the binding activity of rabbit polyclonal antibodies by indirect immunofluorescence method. The specific reactivity of serum antibodies to recombinant proteins was detected by Western blot. Results:Restriction enzyme analysis and DNA sequencing confirmed that the recombinant expression vectors of pET-32a-Gn, pET-32a-Gn1/Gn2/Gn3, pET-32a-Gc1/Gc2, pcDNA3.1-Gn and pcDNA3.1-Gc1/Gc2 were constructed successfully. The relative molecular mass ( Mr) of the expressed recombinant proteins Gn-His, Gn1/Gn2/Gn3-His, Gc1/Gc2-His were approximately 63.4×10 3, 37.1×10 3, 31.9×10 3, 30.8×10 3, 40×10 3 and 54.4×10 3, respectively. The recombinant proteins could be recognized by GTV-positive sheep serum. The titers of polyclonal antibodies against GTV Gn, Gc1 and Gc2 were 1∶409 600, 1∶204 800 and 1∶6 400, respectively. Indirect immunofluorescence assay and Western blot showed that the prepared rabbit polyclonal antibodies could specifically react with the proteins expressed in eukaryotic cells and the recombinant proteins. Conclusions:The recombinant GTV glycoproteins Gn-His and Gc1/Gc2-His were efficiently expressed and purified and characterized with good immunity. The prepared polyclonal antibodies had high titers and good specificity. This study provided reference for further studying the biological function and detection methods of GTV glycoproteins and research on vaccines.

Application of Artificial Intelligence Automatic Diatom Identification System in Practical Cases / 法医学杂志

Objective To discuss the application of artificial intelligence automatic diatom identification system in practical cases, to provide reference for quantitative diatom analysis using the system and to validate the deep learning model incorporated into the system. Methods Organs from 10 corpses in water were collected and digested with diatom nitric acid; then the smears were digitally scanned using a digital slide scanner and the diatoms were tested qualitatively and quantitatively by artificial intelligence automatic diatom identification system. Results The area under the curve （AUC） of the receiver operator characteristic （ROC） curve of the deep learning model incorporated into the artificial intelligence automatic diatom identification system, reached 98.22% and the precision of diatom identification reached 92.45%. Conclusion The artificial intelligence automatic diatom identification system is able to automatically identify diatoms, and can be used as an auxiliary tool in diatom testing in practical cases, to provide reference to drowning diagnosis.

Relationship between Postmortem Interval and FTIR Spectroscopy Changes of the Rat Skin / 法医学杂志

Objective To infer postmortem interval （PMI） based on spectral changes of the dorsal skin of rats within 15 days postmortem using Fourier transform infrared （FTIR） spectroscopy. Methods The rats were sacrificed by cervical dislocation after anesthesia, and then placed at 25 ℃ and relative humidity of 50%. The FTIR spectral data collected from the dorsal skin at PMI points were modeled with machine learning technique. Results There was no significant difference of absorption peak location among all the PMI groups but their peak intensities changed as a function of PMIs. The model for PMI estimation was constructed using partial least squares （PLS） regression, reaching a R2 of 0.92 and a root mean square error （RMSE） of 1.30 d. As shown in variable importance for projection （VIP）, four spectral bands including 1 760-1 700 cm-1, 1 660-1 640 cm-1, 1 580-1 540 cm-1 and 1 460-1 420 cm-1 were determined as important contributions to model prediction. Conclusion Application of the FTIR technique to detect postmortem spectral changes of the rat skin provides a novel proposal for PMI estimation.

Determination of Electrocution Using Fourier Transform Infrared Microspectroscopy and Machine Learning Algorithm / 法医学杂志

Objective To analyze the differences among electrical damage, burns and abrasions in pig skin using Fourier transform infrared microspectroscopy （FTIR-MSP） combined with machine learning algorithm, to construct three kinds of skin injury determination models and select characteristic markers of electric injuries, in order to provide a new method for skin electric mark identification. Methods Models of electrical damage, burns and abrasions in pig skin were established. Morphological changes of different injuries were examined using traditional HE staining. The FTIR-MSP was used to detect the epidermal cell spectrum. Principal component method and partial least squares method were used to analyze the injury classification. Linear discriminant and support vector machine were used to construct the classification model, and factor loading was used to select the characteristic markers. Results Compared with the control group, the epidermal cells of the electrical damage group, burn group and abrasion group showed polarization, which was more obvious in the electrical damage group and burn group. Different types of damage was distinguished by principal component and partial least squares method. Linear discriminant and support vector machine models could effectively diagnose different damages. The absorption peaks at 2 923 cm-1, 2 854 cm-1, 1 623 cm-1, and 1 535 cm-1 showed significant differences in different injury groups. The peak intensity of electrical injury's 2 923 cm-1 absorption peak was the highest. Conclusion FTIR-MSP combined with machine learning algorithm provides a new technique to diagnose skin electrical damage and identification electrocution.

Study on the etiology of rash and fever illness in Pudong New Area of Shanghai from 2010 to 2017 / 中华疾病控制杂志

Objective To investigate the pathogens spectrum and epidemiological characteristics of rash and fever illness (RFIs) from January 2010 to December 2017 in Pudong New Area, in order to provide scientific evidence for the prevention and control ofRFIs.Methods Enzyme-linked immunosorbent assay and real-time fluorescence quantitative polymerase chain reaction were used to detect the pathogens of enterovirus, measles virus, rubella virus and others from 2 831 clinical samples, and statistical analysis was performed.Results Pathogens were found in 1 633 samples in total, accounting for 68.59%. The top 4 viruses in the pathogen spectrum were enterovirus (52.54%), measles virus (28.54%), rubella virus (13.04%), and varicella-zoster virus (3.37%). There was significnat difference in the detection rate of rubella pathogens among patients of different genders(P=0.026). In the pathogen spectrum of infections of different age groups, the detection rate of enteroviruses at the age of 3-6 years was higher than that of other age groups. The detection rate of varicella-zoster virus at the age of 6-18 years old was higher than that of other age groups. The detection rate of virus including measles virus, rubella virus, dengue virus and small DNA virus in age of 18 and older was higher than that of other age groups. There was significant difference in the detection rate of pathogens in different age groups (all P<0.05).The incidence of RFIs was the highest in spring (41.52%) and the lowest in winter (15.00%). There was a statistical difference in the detection rate of enterovirus, measles, rubella and dengue virus in different seasons (P<0.05).Conclusions Enteroviruses and measles viruses are the main pathogens leading to RFIs in Pudong New Area, and the activity level of RFIs pathogens should be monitored for a long time.

Traditional Chinese Medicine as a Remedy for Male Infertility: A Review

Male infertility (MI) is a complex multifactorial disease, and idiopathic infertility accounts for 30% of cases of MI. At present, the evidence for the effectiveness of empirical drugs is limited, and in vitro fertilization is costly and may increase the risk of birth defects and childhood cancers. Therefore, affected individuals may feel obliged to pursue natural remedies. Traditional Chinese medicine (TCM) may represent a useful option for infertile men. It has been demonstrated that TCM can regulate the hypothalamic-pituitary-testicular axis and boost the function of Sertoli cells and Leydig cells. TCM can also alleviate inflammation, prevent oxidative stress, reduce the DNA fragmentation index, and modulate the proliferation and apoptosis of germ cells. Furthermore, TCM can supply trace elements and vitamins, ameliorate the microcirculation of the testis, decrease the levels of serum anti-sperm antibody, and modify epigenetic markers. However, the evidence in favor of TCM is not compelling, which has hindered the development of TCM. This review attempts to elucidate the underlying therapeutic mechanisms of TCM. We also explore the advantages of TCM, differences between TCM and Western medicine, and problems in existing studies. Subsequently, we propose solutions to these problems and present perspectives for the future development of TCM.

Drug resistance and molecular characteration of hemagglutinin and neuraminidase for influenza A H3N2 viruses / 医学研究生学报

Objective　To analyze the variations and drug resistance of influenza A (H3N2) viruses in Jiangsu Province in 2017, and provide evidence for prevention and control strategies on influenza.　Methods　Reverse transcription polymerase chain reaction (RT-PCR) was used for the sequencing of H3N2 subtype influenza strains. The influenza reference sequences were obtained from the global shared influenza site GISAID. The sequence alignment and phylogenetic analysis were performed using MAGE7.0 software. Viral resistance was analyzed by a neuraminidase inhibition assay.　Results　The H3N2 subtype influenza isolates and vaccine strains belonged to the 3C.2a branch of the H3 subtype. Some of the strains showed amino acid mutations on the immune-related sites named N121K, T135K and N171K. The isolates were sensitive to the flu drugs oseltamivir and zanamivir.　Conclusion　The H3N2 epidemic strains in Jiangsu have genetic recombination within subtypes and are still sensitive to neuraminidase inhibitors. As the H3N2 influenza virus mutations continue, a close monitoring of the viral genetic evolution and the drug resistant genes should be guaranteed.

Clinical study of Simiao pill combined with celecoxib in the treatment of acute gouty arthritis / 中国基层医药

Objective To observe the efficacy of Simiao pill combined with celecoxib in the treatment of acute gouty arthritis(AGA). Methods From January 2015 to January 2017,70 patients with AGA in the Central Hospital of Luohe were selected and randomly divided into two groups,with 35 cases in each group. The control group received celecoxib treatment,while the treatment group received Simiao pill combined with celecoxib. The treatment course was 7 days in each group. The clinical efficacy and the blood uric acid ( UA) changes were observed and compared before and after treatment. Results The total effective rate of the treatment group was 91. 4% (32/35), which was remarkably higher than 77. 1% (27/35) of the control group,the difference between the two groups was statistically significant(χ2=4. 381,P ＜0. 05). Before treatment,there was no significant difference in UA level between the treatment group and control group(P＞0. 05). After treatment,the level of UA in the treatment group was (402. 17 ± 18. 43) μmol/L,which was lower than (475. 29 ± 37. 82) μmol/L in the control group,the difference between the two groups was statistically significant (t= －11. 051,P＜0. 05). Conclusion The clinical efficacy of Simiao pill combined with celecoxib in the treatment of AGA is effective,and is worthy of clinical promotion.

Establishment of the Mathematical Model for PMI Estimation Using FTIR Spec-troscopy and Data Mining Method / 法医学杂志

Objective To analyse the relationship between Fourier transform infrared （FTIR） spectrum ofrat's spleen tissue and postmortem interval （PMI） for PMI estimation using FTIR spectroscopy combinedwith data mining method. Methods Rats were sacrificed by cervical dislocation, and the cadavers were placed at 20 ℃. The FTIR spectrum data of rats' spleen tissues were taken and measured at different time points. After pretreatment, the data was analysed by data mining method. Results The absorption peak intensity of rat's spleen tissue spectrum changed with the PMI, while the absorption peak position was unchanged. The results of principal component analysis （PCA） showed that the cumulative contribution rate of the first three principal components was 96%. There was an obvious clustering tendency for the spectrum sample at each time point. The methods of partial least squares discriminant analysis （PLS- DA） and support vector machine classification （SVMC） effectively divided the spectrum samples with different PMI into four categories （0-24 h, 48-72 h, 96-120 h and 144-168 h）. The determination coefficient （R2） of the PMI estimation model established by PLS regression analysis was 0.96, and the root mean square error of calibration （RMSEC） and root mean square error of cross validation （RMSECV） were 9.90 h and 11.39 h respectively. In prediction set, the R2 was 0.97, and the root mean square error of prediction （RMSEP） was 10.49 h. Conclusion The FTIR spectrum of the rat's spleen tissue can be effectively analyzed qualitatively and quantitatively by the combination of FTIR spectroscopy and data mining method, and the classification and PLS regression models can be established for PMI estimation.

Necessity of setting up the course on clinical healthcare-associated infection according to case-based teaching method in medical higher education / 中国感染控制杂志

Objective To explore the necessity of setting up the course on clinical healthcare-associated infection (HAI) and effectiveness of the case-based teaching method in medical higher education.Methods 198 students who underwent internship in a hospital between July 2015 and July 2016 were selected,according to whether they selected clinical HAI coures,they were divided into course selective group(n =107,adopted case-based teaching method) and unselective group(n =91),questionnaire survey on the knowledge and attitude of HAI was carried out.Results The average score on HAI in selective group was higher than that of unselective group([85.3 ± 1.6] vs [58.3 ± 1.8],t =111.72,P＜0.01).Before and after conducted case-based teaching method,21.49％ and 47.66％ of students actively studied respectively,difference was significant (x2 =16.195,P＜0.01).Conclusion It is necessary to carry out a systematic course on HAI,case-based teaching method can improve the learning enthusiasm of students.

Genetic origin of avian influenza A H7N4 virus causing a case of human infection in China , 2018 / 中华微生物学和免疫学杂志

Objective To analyze the molecular characteristics and genetic origin of a novel avian influenza A H7N4 virus casuing a case of human infection in China. Methods Specimens were collected from the patient and chickens and ducks kept by the patient and neighbours and then detected by real-time quantitative PCR. The original specimens and virus isolates were analyzed by next-generation sequencing technology to obtain viral whole-genome sequences. Pairwise sequence alignments and phylogenetic analysis were performed by BLASTs,ClustalX and MEGA 6. 1 softwares. Results In January 2018, a human case infected with avian influenza A H7N4 virus was confirmed. Seven H7N4 viruses were isolated from speci-mens collected from chicken and ducks kept in the patient`s backyard. H7N4 virus was a novel reassortant vi-rus with all eight gene fragments derived from wild waterfowl in Eurasia. HA protein contained a single basic amino acid residue R in cleavage site, suggesting that H7N4 virus was low pathogenic. The receptor-binding sites of HA had QSG at 226-228 residues, which indicated that the virus retained avian-type receptor speci-ficity (SAα2-3Gal). Different from H7N4 viruses in avian, the virus isolated from the patient had substitu-tion at position 627 ( E→K) in PB2 protein, which might increase its adaptation in human host. Conclusion This study reported a case of human infection with a novel reassortant avian influenza A H7N4 virus, which revealed that the traditional backyard breeding models might facilitate cross-species transmission of avian in-fluenza viruses in southern China.

Infrared Spectral Characteristics of Electrical Injuries on Swine Skin Caused by Different Voltages Based on Machine Learning Algorithms / 法医学杂志

Objective 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-1and 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-1band was used to identify the different voltages induced skin injuries.The OSC could further optimize the robustness of the 3 600-2 800 cm-1band model.Conclusion It is feasible to identify electrical skin injuries caused by different voltages by using FTIR-MSP technique along with machine learning algorithms.

Research Status of New Designer Drug Methcathinone in Forensic Toxicology / 法医学杂志

Methcathinone, a new cathinone designer drug, which is structurally similar to amphetamine analogs, is a central nervous stimulant.Recently, there has been a worldwide rise in its popularity and abuse, and a growing number of cases with disability or even death is reported in several countries, resulting in public concern.The typical symptoms include accelerated heartbeat, high temperature, anxiety, depression, etc.Forensic studies on its toxicity mechanism are rare.This article reviews its toxicological effects, poisoning symptoms, poisoning and addiction mechanisms, and detection methods, to provide theoretical reference for future studies and guidance for related forensic identification.

Effects of Temperature on FTIR Spectral Characteristics of Renal Tissue in Rats after Death / 法医学杂志

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.