Research Status of New Designer Drug Methcathinone in Forensic Toxicology

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.

Analysis of Causes of Death and Related Factors of 102 Perinatal Infants in Chongqing

OBJECTIVES

To analyze the causes of perinatal death and related factors from the perspective of forensic medicine, and to provide references for reducing perinatal mortality and guidance for forensic identification.

METHODS

A retrospective analysis was performed on 102 cases of perinatal autopsy with clinical data from the Department of Forensic Medicine of Chongqing Medical University in 2004-2016.

RESULTS

Of the 102 cases of perinatal deaths, 66 （64.71%） were neonatal deaths, 24 （23.53%） were stillborn foetuses, and 12 （11.76%） were stillbirths. Among the 66 neonatal death cases, 39 （59.09%） died within 1 d, 19 （28.79%） died within 1-3 d, and 8 （12.12%） died within >3-7 d of birth. The top 3 causes of neonatal death were pulmonary diseases, congenital malformation, umbilical cord and placental abnormalities. The causes of stillborn foetus and stillbirth were mainly umbilical cord and placental abnormalities, and intrauterine asphyxia.

CONCLUSIONS

Pulmonary diseases, umbilical cord and placental abnormalities, and congenital malformations are the main causes of perinatal death. In order to reduce the perinatal mortality, pre-pregnancy examination and prenatal care should be strengthened, and the knowledge of pregnancy care should be popularized.

[Analysis on the trend of cancer incidence and age change in cancer registry areas of China, 2000 to 2014]

Objective: To analyze the trends of cancer incidence and age changes in China with using cancer registration data, and to provide evidence for the development of cancer prevention and control. Methods: Twenty-two cancer registries with continuous (2000-2014) data were selected. The incidence of different sex and regional population, the standardized incidence rate by Chinese population, the average annual change percentage (AAPC) and annual change percentage(APC) were calculated. Age-period-cohort model were used to analyze the changes of cancer incidence, age-adjusted mean ages. The age-standardized proportion of 2000 and 2014 with were compared. Results: The cancer incidence in China increased by 3.9% (95%CI: 3.7%-4.1%) from 2000 to 2014 in APC, and the age-standardized incidence rate increased by 1.2% (95%CI: 1.0%-1.4%) in AAPC. The age-specific incidence showed that each age groups increased significantly in female, ranged between 0.9% to 6.0%. The APC in male aged from 60 years old showed decline trend, the APC in 60-69, 70-79, ≥80 years old were -0.2, -0.3, -0.3, while in the population aged 0-29, 30-39 years old increased dramatically, APC were 3.5, 2.0. Female under 60 also increased, and APC in 0-29, 30-39, 40-49, 0-59 years old were 5.7, 6.0, 3.4, 2.9, respectively. The mean age of patients diagnosed with cancer were increased during the past 15 years, with about 0.11 years per year increased. However, the mean age of the patients diagnosed with cancer showed decreased trend by 0.13 years after age structure adjusted. Conclusion: The trend of mean age for cancer incidence in China were getting younger than before, and the trend in women is more obviously than in man.

[Incidence trend and change in the age distribution of female breast cancer in cancer registration areas of China from 2000 to 2014]

Objective: To estimate the incidence trend and change in the age distribution of female breast cancer in cancer registry areas in China from 2000 to 2014. Methods: 22 cancer registries in China with continuous monitoring data from 2000 to 2014 were selected. All datasets were checked and evaluated based on data quality control criteria and were included in the analysis. The cancer registries covered 675 954 193 person-years, including 342 010 930 person-years of male and 333 943 263 person-years of female. Female breast cancer cases (International Classification of Diseases-10(th) Revision: C50) were extracted. Crude incidence rate (CR), age-standardized incidence rate by Chinese standard population(ASIRC), annual percent change (APC), crude and adjusted mean age at onset were calculated. Incidence rates stratified by regions and age groups were calculated. Results: Female breast cancer incidence rate significantly increased from 31.90/100 000 in 2000 to 63.30/100 000 in 2014. Incidence rate increased rapidly from 2000 to 2008 (CR: APC=6.5%, 95%CI: 5.3%-7.8%; ASIRC: APC=4.6%, 95%CI: 3.6%-5.7%). Its increment slowed down from 2008-2014 (CR: APC=3.2%, 95%CI: 1.4%-5.1%; ASIRC: APC=1.4%, 95%CI:-0.1%-2.9%). The crude mean age at onset increased from 54.4 in 2000 to 57.0 in 2014. Adjusted mean age at onset remained around 54.3 in 2014. Crude mean age at onset increased significantly over time in all registry areas (β=0.192, P<0.001), urban (β=0.205, P<0.001) and rural (β=0.092, P=0.014) areas, while adjusted mean age at onset remained stable in all registry areas (β=0.009, P=0.289), urban (β=0.017, P=0.139) and rural (β=-0.054, P=0.109) areas. Conclusion: Female breast cancer incidence rate in China increased from 2000 to 2014. Aging of the population resulted in a significant increase in crude mean age at onset. After age adjustment, no significant changes in age distribution were found.

[The incidence and mortality of lung cancer in China, 2014]

Objective: To estimate lung cancer incidence and mortality in China using population-based cancer registry data in 2014 collected by National Central Cancer Registry of China (NCCRC). Methods: 449 cancer registries submitted cancer registry data in 2014. All datasets were evaluated and 339 registries' data which met the quality control criteria of NCCRC were analyzed. Numbers of new lung cancer cases and deaths were estimated using calculated incidence and mortality rates and corresponding national population stratified by areas, sexes and age groups. The standard population of Chinese census in 2000 and world Segi' s population were applied to calculate age-standardized incidence and mortality rates in China and worldwide, respectively. Results: A total of 781, 500 new lung cancer cases were diagnosed in 2014. The crude incidence rate was 57.13 per 100 000 and the age-standardized incidence rates by Chinese standard population (ASIRC) and by world standard population (ASIRW) were 36.71 per 100 000 and 36.63 per 100 000, respectively. The cumulative incidence rate (0-74 years old) was 4.50%. Lung cancer was the most common cancer in male (ASIRW: 50.04 per 100 000) and the second most common cancer in female (ASIRW: 23.63 per 100 000). The incidence rates were slightly similar in urban areas and in rural areas (ASIRW: 36.64 per 100 000 vs 36.56 per 100 000). A total of 626 400 lung cancer deaths were reported. The crude mortality rate was 45.80 per 100 000 and the age-standardized mortality rates by Chinese standard population (ASMRC) and by world standard population (ASMRW) were 28.49 per 100 000 and 28.31 per 100 000, respectively. The cumulative mortality rate (0-74 years old) was 3.32%. Lung cancer was the most common cause of cancer deaths both in male (ASMRW: 40.21 per 100 000) and female (ASMRW: 16.88 per 100 000). The mortality rate was slightly higher in rural areas than in urban areas (ASMRW: 28.63 per 100 000 vs 28.04 per 100 000). Both lung cancer incidence and mortality rates increased with age, and the peak age was 80-84 years group. Conclusions: The disease burden of lung cancer is heavy in China. Efficient national health policies and prevention and control strategies against lung cancer should be promoted.

[Incidence and mortality of stomach cancer in China, 2013]

Objective: To estimate the incidence and mortality of stomach cancer in China based on the cancer registration data in 2013, collected by the National Central Cancer Registry (NCCR). Methods: There were 347 cancer registries that submitted stomach cancer incidence and deaths occurred in 2013 to NCCR. After evaluating the data quality, 255 registries' data were accepted for analysis and stratified by areas (urban/rural), sex, and age group. Combined with data on national population in 2013, the nationwide incidence and mortality of stomach cancer were estimated. Chinese population census in 2000 and Segi's population were used for age-standardized incidence/mortality rates. Results: Qualified 255 cancer registries covered a total of 226 494 490 populations (111 595 772 in urban and 114 898 718 in rural areas). The percentage of cases morphologically verified and death certificate-only cases were 76.27% and 1.98%, respectively, and the mortality to incidence rate ratio was 0.72. It is estimated that there were 427 000 new cases for stomach cancer nationwide, with a crude incidence rate of 31.38 per 100 000 (42.85 per 100 000 in males, 19.33 per 100 000 in females). The age-standardized incidence rates by Chinese standard population (ASR China) and by world standard population (ASR world) were 21.40 per 100 000 and 21.32 per 100 000, respectively, with a cumulative incidence rate (0-74 age years old) of 2.66%. The crude and ASR China incidence rates of stomach cancer in urban areas were 27.80 per 100 000 and 18.48 per 100 000, respectively, whereas those were 35.54 per 100 000 and 24.93 per 100 000 in rural areas. It is estimated that there were 301 000 deaths for stomach cancer nationwide, with a crude mortality rate of 22.13 per 100 000 (29.85 per 100 000 in males, 14.03 per 100 000 in females). The ASR China and ASR world mortality rates were 14.68 per 100 000 and 14.54 per 100 000, respectively, with a cumulative mortality rate (0-74 years old) of 1.70%. The crude and ASR China mortality rates were 18.94 per 100 000 and 12.20 per 100 000 in urban areas, respectively, whereas those were 25.84 per 100 000 and 17.67 per 100 000 in rural areas. Conclusions: There is still a heavy burden of stomach cancer in China. The burden and patterns of stomach cancer shows different gender and urban-rural differences. Prevention and control strategies should be implemented referring to local status.

[Change in peripheral nervous conduction velocity in patients with occupational chronic mercury poisoning and related influencing factors]

Objective: To investigate the change in peripheral nervous conduction velocity in patients with occupational chronic mercury poisoning and related influencing factors. Methods: From February 2011 to December 2014, urinary mercury examination and neural electromyography were performed for 104 patients with occupational chronic mercury poisoning. The data on age, type of work, working years of mercury exposure, and past medical history were collected, and peripheral nervous conduction velocity and its correlation with age, working years of mercury exposure, and urinary mercury concentration were analyzed. Results: All the 104 patients with occupational chronic mercury poisoning had a mean of 45.37±9.82 years, median (P(25), P(75)) working years of 7 (3, 11) , and a median (P(25), P(75)) urinary mercury concentration of 88.50 (56.25, 163.03) μg/g Cr. The major clinical manifestations of peripheral nerve injuries were numbness of extremities (20.2%) , hypopselaphesia/hypalgesia or hyperpselaphesia/hyperalgesia (9.6%) , and bone/muscle pain in the extremities (6.7%) . Neural electromyography showed an increase in denervation potential (fibrillation potential or positive sharp wave) and a detection rate of abnormal peripheral nervous conduction velocity as high as 65.4%. The patients with an older age and more working years had a higher incidence rate of abnormal sensory conduction velocity of the ulnar nerve. There were significant reductions in motor and sensory conduction velocities of the median nerve, motor and sensory conduction velocities of the ulnar nerve, motor conduction velocity of the common peroneal nerve, and the sensory conduction velocity of the superficial peroneal nerve (P<0.05) , with the increase in urinary mercury concentration. Conclusion: Patients with occupational mercury poisoning have a high rate of abnormal neural electromyographic findings, which can be used as an important method for early identification of chronic peripheral nerve injuries induced by mercury poisoning. The degree of peripheral nerve injuries increases with the increasing time of mercury exposure and urinary mercury concentration.

[Analysis of clinical features in patients with pneumoconiosis complicated with pulmonary emphysema]

Objective: To investigate the clinical features of pneumoconiosis complicated with pulmo-nary emphysema. Methods: selected 868 patients with pneumoconiosis were selected from December 2015 to December 2016 in Hunan occupational disease prevention and treatment hospital. Collected the results of high-resolution spiral CT, arterial blood gas, ECG, pulmonary function and MRC score. The subjects were divided into pneumoconiosis complicated with pulmonary emphysema group and simple pneumoconiosis group accord-ing to the results of HRCT. The smoking, MRC score, pulmonary function, blood gas and complications were compared. Results: A total of 868 patients were enrolled in the study. Emphysema 232 people, accounting for 26.73%. The incidence of emphysema in the first phase of pneumoconiosis was 12.69%, and the incidence rate of emphysema in pneumoconiosis was 17.03%, The incidence of three Stage pneumoconiosis was highest, up to 60.76%, the incidence of emphysema increased with the increase of stages of pneumoconiosis (P=0.000) .The smoking index of pneumoconiosis combined with emphysema group was significantly higher than that of simple pneumoconiosis group (P<0.01) . The MRC score of pneumoconiosis complicated with pulmonary em-physema group was higher than that of simple pneumoconiosis group (P=0.000) . In pneumoconiosis complicat-ed with pulmonary emphysema group the FEV(1.0)%, FVC%, FEV(1.0)/FVC, DLCO%, oxygen partial pressure were significantly lower than that of simple pneumoconiosis group (P≤0.05) . The combined rate of Bullae of lung in pneumoconiosis complicated with pulmonary emphysema group was higher than that of simple pneumo-coniosis group (P<0.01) . Conclusion: pneumoconiosis stage and smoking. Patients with pneumoconiosis com-plicated with pulmonary emphysema had heavier breathing difficulties, more serious pulmonary function and active endurance, the degree of hypoxia is more serious, and had a higher incidence of complications. The pul-monary function of pneumoconiosis complicated with pulmonary emphysema is not consistent with the typical CPFE.

[Clinical phenotypes of TBC1D24 gene related epilepsy]

Objective: To summarize the clinical features of TBC1D24 gene mutations associated with epilepsy. Methods: All the patients with TBC1D24 gene compound heterozygous mutations were retrospectively collected at the Pediatric Department of Peking University First Hospital from March 2015 to July 2017, and the features of clinical manifestations, electroencephalogram, and neuroimaging were analyzed. Results: Eighteen cases with TBC1D24 gene compound heterozygous mutations were included. The age of seizure onset was 1 day to 8 months, and the median age was 90 days. Seizure types included generalized tonic-clonic seizures (GTCS) in 3 cases, focal seizures in 18 cases, myoclonus in 18 cases, and 17 cases had focal myoclonus and myoclonus status. The focal myoclonus involving one or multiple muscle groups, sometimes migrating and alternating, lasting up to minutes to several days, and could be terminated by sleep or sedation drugs. In 11 cases, myoclonus was exacerbated by fever or infections, and 2 cases developed into myoclonic status during infection, in a severe case with the loss of consciousness. The magnetic resonance imaging (MRI) of seven patients was abnormal, including cerebral atrophy or cerebellar atrophy with abnormal signals. Segment myoclonus was captured in 10 patients, but without correlated epileptiform discharges. There were ten cases had varying degrees of developmental delay, 7 were normal, and one patient died of status epilepticus at the age of 4 months. Three cases had hearing disorders. In the 18 patients, the clinical phenotype of 4 cases consisted of epilepsy of infancy with migrating focal seizures, 2 with progressive myoclonus epilepsies, 1 with Dravet syndrome, 1 with DOORS syndrome, and 3 with unclassified epileptic encephalopathy. Conclusions: The clinical feature of TBC1D24 gene mutation related epilepsy was focal myoclonus, and tended to develop into myoclonic status epilepticus, and could be aggravated by infections, and terminated by sleep or sedation drugs. Mental retardation involved or not, neuroimaging could present with cerebral atrophy or cerebellar atrophy with abnormal signals.

An Electroelastic Solution for Functionally Graded Piezoelectric Circular Plates under the Action of Combined Mechanical Loads

In this study, we obtained an electroelastic solution for functionally graded piezoelectric circular plates under the action of combined mechanical loads which include the uniformly distributed loads on the upper surface of the plate and the radial force and bending moment at the periphery of the plate. All electroelastic materials parameters are assumed to vary according to the same gradient function along the thickness direction. The influence of different functionally graded parameters on the elastic displacement and elastic stress, as well as the electric displacement and electric potential, was discussed by a numerical example. The solution presented in this study is not only applicable to the case of combined loads, but also to the case of a single mechanical load. In addition, this solution reflects the influence of the function gradient on the pure piezoelectric plate, which is helpful to the refined analysis and optimization design of similar structures.

[Spectrum of mutations in benign familial neonatal-infantile epilepsy]

Objective: To investigate the spectrum of mutations in families with benign familial neonatal-infantile epilepsy (BFNIE) . Methods: Clinical data and peripheral blood DNA samples of all BFNIE probands and their family members were collected from Peking University First Hospital between December 2012 and April 2016. Clinical phenotypes of affected members were analyzed. Genomic DNA was extracted from peripheral blood samples with standard protoco1. Mutations in PRRT2 were screened using Sanger sequencing. For families that PRRT2 mutations were not detected by Sanger sequencing, candidate gene mutations were further screened by next-generation sequencing for epilepsy. Results: A total of 7 families were collected. Of the 30 affected members, 15 were male and 15 were female. The age of epilepsy onset was from 2 days to 6 months. Genetic testing led to the identification of gene mutations in all families. One family had the PRRT2 hotspot mutation (c.649dupC). Three families had missense SCN2A mutations (c.2674G>A/p.V892I, c.2872A>G/p.M958V, and c.2627A>G/p.N876S) . Both c.2872A>G/p.M958V and c.2627A>G/p.N876S were novel SCN2A mutations. Three families had KCNQ2 mutations. Two of them had missense mutations (c.958G>A/p.V320I and c.998G>A/p.R333Q) . The KCNQ2 mutation c.958G>A/p.V320I was novel. One family had a gene deletion of KCNQ2, which also extended to the adjacent gene, CHRNA4; and the deletion involved all the exons of KCNQ2 and CHRNA4. Conclusions: Mutations in KCNQ2, SCN2A, and PRRT2 are genetic causes of BFNIE in Chinese families. The detection rate for gene mutations is high in BFNIE families. KCNQ2 and SCN2A mutations are common in BFNIE families. SCN2A mutations (c.2872A>G/p.M958V and c.2627A>G/p.N876S) and KCNQ2 mutation (c.958G>A/p.V320I) are novel mutations.

[Application of scalp-recorded high-frequency oscillations in epileptic encephalopathy with continuous spike-and-wave during sleep]

OBJECTIVE

To investigate the clinical significance of high-frequency oscillations (HFOs) on scalp electroencephalography (EEG) in patients with epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS).

METHODS

Twenty-one CSWS patients treated for epilepsy from January 2006 to December 2016 in Pediatric Department of Peking University First Hospital were enrolled into the study. Selected clinical variables including gender, age parameters, seizure frequencies and antiepileptic drugs were compared between (a). HFO-positive group and HFO-negative group before methylprednisolone treatment and (b). excellent seizure outcome group and not-excellent seizure outcome group after methylprednisolone treatment. Interictal HFOs and spikes in pre- and post-methylprednisolone scalp EEG were measured and analyzed.

RESULTS

Before methylprednisolone treatment, there were 12 of 21 (57%) CSWS patients had HFOs, with a mean value 43.17 per 60 s per patient. The 12 patients with HFOs tended to have more frequent epileptic negative myoclonus/atonic/myoclonus/atypical absences than those without HFOs in a month before methylprednisolone treatment. A total of 518 HFOs and 22 592 spikes were found in the pre-methylprednisolone EEG data of 21 patients, and 441 HFOs (86%) were associated with spikes. The highest amplitudes of HFOs were significantly positively correlated with that of spikes (r=0.279, P<0.001). Rates reduced by methylprednisolone treatment were statistically significant for both HFOs (P=0.002) and spikes (P=0.006). The percentage of reduction was 91% (473/518) and 39% (8 905/22 592) for spikes and HFOs, respectively. The percentage of spike and HFOs changes was respectively 100% decrease and 47% decrease in the excellent seizure outcome group, and they were 79% decrease and 18% increase in the not-excellent seizure outcome group.

CONCLUSION

Prevalence of HFOs might reflect some aspect of epileptic activity. HFOs were more sensitive to methylprednisolone treatment than spikes and had a good correlation with the prognosis of seizures, and HFOs could be applied to assess epilepsy severity and antiepileptic therapy.

[Progress of research on the association between air pollution and prevalence of major cancers]

Being an undisputed risk factor of cancer, air pollution is posing a huge threat to the health on human beings. In this article, we introduced the composition of air pollution, and the standards on air quality which was set by both World Health Organization and the Chinese government. We also summarized the most recent research findings on the association between air pollution and the risk of lung, breast, bladder and other major cancers.

[Incidence and mortality of female breast cancer in China, 2014]

Objective: To estimate the incidence and mortality of female breast cancer in China based on the cancer registration data in 2014, collected by the National Central Cancer Registry (NCCR), and to provide support data for breast cancer prevention and control in China. Methods: There were 449 cancer registries submitting female breast cancer incidence and deaths data occurred in 2014 to NCCR. After evaluating the data quality, 339 registries' data were accepted for analysis and stratified by areas (urban/rural) and age group. Combined with data on national population in 2014, the nationwide incidence and mortality of female breast cancer were estimated. Chinese population census in 2000 and Segi's population were used for age-standardized incidence/mortality rates. Results: Qualified 339 cancer registries covered a total of 288 243 347 populations (144 061 915 in urban and 144 181 432 in rural areas) in 2014. The morphology verified cases (MV%) accounted for 87.42% and 0.59% of incident cases were identified through death certifications only (DCO%), with mortality to incidence ratio of 0.24. The estimates of new breast cancer cases were about 278 900 in China in 2014, accounting for 16.51% of all new cases in female. The crude incidence rate, age-standardized rate of incidence by Chinese standard population (ASRIC), and age-standardized rate of incidence by world standard population (ASRIW) of breast cancer were 41.82/100 000, 30.69/100 000, and 28.77/100 000, respectively, with a cumulative incidence rate (0-74 age years old) of 3.12%. The crude incidence rates and ASRIC in urban areas were 49.94 per 100 000 and 34.85 per 100 000, respectively, whereas those were 31.72 per 100 000 and 24.89 per 100 000 in rural areas. The estimates of breast cancer deaths were about 66 000 in China in 2014, accounting for 7.82% of all the cancer-related deaths in female. The crude mortality rate, age-standardized rate of mortality by Chinese standard population(ASRMC) and age-standardized rate of mortality by world standard population (ASRMW) of breast cancer were 9.90/100 000, 6.53/100 000, and 6.35/100 000, respectively, with a cumulative mortality rate of 0.69%. The crude mortality rates and ASRMC in urban areas were 11.48 per 100 000 and 7.04 per 100 000, respectively, whereas those were 7.93 per 100 000 and 5.79 per 100 000 in rural areas. The incidence and mortality rates of breast cancer were higher in areas than those in rural areas. The age-specific incidence rates of breast cancer increased greatly after 20 years old and peaked at the age group of 55-60. The age-specific mortality rates increased rapidly with age, particularly after 25 years old. They remained at a relative stable level from 55 to 65 years of age, and then increased dramatically and peaked in the age group of 85 and above. Conclusions: Breast cancer is still one of the most common malignant tumor threatening to famale health in China. The disease is more prevalent in urban areas at the age group of 55-60. Comprehensive prevention and control strategies referring to local status and age groups should be carried out to reduce the burden of breast cancer.

Theoretical Study on Synchronous Characterization of Surface and Interfacial Mechanical Properties of Thin-Film/Substrate Systems with Residual Stress Based on Pressure Blister Test Technique

In this study, based on the pressure blister test technique, a theoretical study on the synchronous characterization of surface and interfacial mechanical properties of thin-film/substrate systems with residual stress was presented, where the problem of axisymmetric deformation of a blistering film with initial stress was analytically solved and its closed-form solution was presented. The expressions to determine Poisson's ratios, Young's modulus, and residual stress of surface thin films were derived; the work done by the applied external load and the elastic energy stored in the blistering thin film were analyzed in detail and their expressions were derived; and the interfacial adhesion energy released per unit delamination area of thin-film/substrate (i.e., energy release rate) was finally presented. The synchronous characterization technique presented here has theoretically made a big step forward, due to the consideration for the residual stress in surface thin films.

A Novel AdaBoost Framework With Robust Threshold and Structural Optimization

The AdaBoost algorithm is a popular ensemble method that combines several weak learners to boost generalization performance. However, conventional AdaBoost.RT algorithms suffer from the limitation that the threshold value must be manually specified rather than chosen through a self-adaptive mechanism, which cannot guarantee a result in an optimal model for general cases. In this paper, we present a generic AdaBoost framework with robust threshold mechanism and structural optimization on regression problems. The error statistics of each weak learner on one given problem dataset is utilized to automate the choice of the optimal cut-off threshold value. In addition, a special single-layer neural network is employed to provide a second opportunity to further adjust the structure and strength the adaption capability of the AdaBoost regression model. Moreover, to consolidate the theoretical foundation of AdaBoost algorithms, we are the first to conduct a rigorous and comprehensive theoretical analysis on the proposed approach. We prove that the general bound on the empirical error with a fraction of training examples is always within a limited soft margin, which indicates that our novel algorithm can avoid over-fitting. We further analyze the bounds on the generalization error directly under probably approximately correct learning. The extensive experimental verifications on the UCI benchmarks have demonstrated that the performance of the proposed method is superior to other state-of-the-art ensemble and single learning algorithms. Furthermore, a real-world indoor positioning application has also revealed that the proposed method has higher positioning accuracy and faster speed.

[Advances on nanoparticles-tagged visual test strips for the rapid detection of pesticides]

The residue of the pesticides affects seriously the quality and safety of traditional Chinese medicine. Pesticide residue has caused ever-growing attention of people at home and abroad. Rapid detection techniques used for rapid screening of pesticide residues have expanded in a fast progress. As one of the fast development methods of rapid detection, visualization test strip based on nanoparticle has received much concern in recent years. This article focused on the classification of detection test strips and key factors on the fabrication of nanoparticle-based visualization test strips used in small molecule pesticides. Moreover, a wide application of nanoparticles-tagged test strips on pesticide residue was reviewed including single residue detection, multi residue detection, as well as quantitative analysis. Finally, the future application of visual test strip for detecting of pesticide residues in traditional Chinese medicine was forecasted, intending to provide the reference for rapid detection techniques on pesticide residues screening in herbal medicine industry.

[Research progresses and formulation development of natural anti-mildew agents based on Chinese herbal medicines]

Owing to the intrinsic factors and some extrinsic environmental conditions, many foods, agricultural products and Chinese materia medicas (CMMs), if not handled properly in the processes of growth, harvesting, processing and storage, can be easily contaminated by all kinds of molds to produce mycotoxins of serious toxicity, which will not only affect the quality, safety and effectiveness of CMMs, but also result in potential threatens to human and animal's health and life. Therefore, in recent decades, it has become the focus on how to prevent and control the foods, agricultural products and CMMs from being moldy and producing toxicity for scientific preservation. Many Chinese herbal medicines (CHMs) especially those with high content of volatile oils with strong antifungal activities have been applied for the scientific preservation of foods, agricultural products and CMMs. Based on these situations, natural anti-mildew agents have been further developed and made into some useful dosage forms, such as tablets, aerosol, liposomes and inclusion, which will not only greatly expand the application scope of CHMs to make the use of anti-mildew agents more convenient, but also achieve the sustained or controlled release of the antifungal effect for scientific preservation of foods, agricultural products and CMMs.

[Clinical and genetic characteristics of Williams-Beuren syndrome: 2 cases report]

To explore the clinical and genetic characteristics of Williams-Beuren syndrome (WBS) and to raise awareness of the disease. The characteristics of clinical manifestations, personal history, cardiac ultrasound, brain magnetic resonance imaging (MRI), electroencephalogram (EEG) and chromosome detection results of two cases with WBS were analyzed. The two patients were both male and the age was 11 months and 1 day, and 9 months and 9 days, respectively. They both suffered from cardiovascular malformation: case one presented supravalvular aortic stenosis, and case two showed atrial septal defect and patent ductus arteriosus. Both of the cases were exhibited characteristic facial features of WBS, including full orbital, spherical nose, flat nasal bridge, long philtrum and thick lips. For the mental development, case one displayed moderate to severe developmental retardation, and case two showed severe developmental retardation. In addition, case one presented bilateral indirect inguinal hernia and hydrocele, and case two manifested feeding difficulties, buried penis and infantile spasms. Personal history: case one's mother had tocolytic therapy during pregnancy period, and case one was born at full-term by cesarean section due to amniotic fluid pollution. Supplementary examination: brain MRI of the two cases were no significant abnormalities; the EEG of case two showed hypsarrhythmia, and the epileptic spasms were recorded. Chromosome detection results: case one was identified as 7q11.23 deletion including the fragment deletion mutation of elastin (ELN) gene by multiplex ligation dependent probe amplification method, and case two was found with 7q11.21q11.23 deletion by high resolution G-band method. The two cases with WBS both had cardiovascular malformations, special facial features, mental retardation and connective tissue or urinary system abnormality. The supravalvular aortic stenosis of case one may be associated with the deletion of ELN gene, and the occurrence of epilepsy of case two may be related to the q11.21 deletion beyond the 7q11.23 region.

[Clinical and genetic characteristics and detection of urinary pipecolic acid in pyridoxine dependent epilepsy]

OBJECTIVE

To analyze the clinical and genetic characteristics of patients with pyridoxine dependent epilepsy (PDE), and build a method to detect and analyze the concentration of urinary pipecolic acid in PDE patients receiving pyridoxine treatment.

METHOD

Twelve patients (8 were male, 4 were female) were diagnosed as PDE in Peking University First Hospital between April 2012 and September 2015. The clinical manifestations, diagnosis and treatment process, video-electroencephalogram, magnetic resonance imaging were retrospectively analyzed. ALDH7A1 gene was detected using Sanger sequencing or targeted next-generation sequencing. The concentration of urinary pipecolic acid in PDE patients was detected with gas chromatography-mass spectrometry (GC-MS), as well as in some non-PDE children served as normal control. All controls, 58 cases totally, were neonates born in our hospital or children came to our hospital for reasons such as syncope (without disturbing pipecolic acid metabolism) from November 2015 to January 2016. Of them, 25 were ≤6 months old(14 were male, 11 were female), 33 were >6 months old(14 were male, 19 were female). The Student's t-test or Mann-Whitney U test was used for comparing the pipecolic acid between the two groups. Correlation analysis was conducted using Pearson or Spearman test.

RESULT

Of the 12 patients, seven of them were abnormal at birth. The age of epilepsy onset was from 5 h to 5 months, within 10 d in 8 patients. After a diagnostic delay time of 15 d to 20 months, seizures in all patients were controlled by pyridoxine monotherapy, at a dose of higher than 10.0 mg/(kg·d) in 10 patients, and 8.5 and 2.5 mg/(kg·d) in the other 2 patients respectively. The range of maintenance dose was 2.5-20.0 mg/(kg·d) during the follow up. Interictal electroencephalogram showed nonspecific abnormality in 10, normal in 2. Brain magnetic resonance imaging showed nonspecific abnormality in 7, normal in 5. ALDH7A1 mutations were found in all patients, including 15 different mutation sites, four of which were never reported before. Splicing mutation IVS11+ 1G>A was carried in 6 patients, with a frequency of 25% (6/24). At the last follow-up, eleven patients were in various degree of psychomotor development delay, including the 4 patients with severe delay in whom birth abnormalities presented, and no significant delay was found in one patient. The concentration of urinary pipecolic acid in control: age ≤6 months, median 8.47 (0.46-35.33) mmol/mol creatinine; age >6 months, median 0.66 (0.12-3.52) mmol/mol creatinine. The concentration of urinary pipecolic acid was different between two groups of control (Z=-5.464, P<0.01). Twelve patients were all older than 6 months when they were tested, and the concentration was only mildly elevated in one patient, the range of 12 patients was 0.14-4.08 mmol/mol creatinine. The concentration was not significantly different between the control with age >6 months and our PDE patients (Z=-0.655, P>0.05). There were no significant correlations between the concentration of urinary pipecolic acid and the initial dose or maintenance dose at last follow-up of pyridoxine (r=0.418 and 0.166, P=0.176 and 0.607).

CONCLUSION

Seizures start in early infancy in most PDE patients. The splicing mutation IVS11+ 1G>A is supposed to be a probable"hotspot"mutation with a high frequency in Chinese PDE patients. Most patients have different levels of psychomotor development delay after seizures are controlled, and the patients with birth abnormalities may have worse outcomes. No relationships between the diagnostic delay time and the development outcome are found. The concentration of urinary pipecolic acid can return to normal during treatment with pyridoxine.