Objective To investigate the killing effect of polymethylmethacrylate (PMMA) on spinal metastasis of transplanted VX2 carcinoma in experimental rabbit models. Methods Spinal metastasis of transplanted VX2 carcinoma model was successfully established in 18 rabbits. The experimental rabbits were randomly and equally divided into three groups with 6 rabbits in each group. Under CT guidance , PMMA or saline was injected into the center of VX2 tumor; in group A 0.3 ml of PMMA was used, in group B 0.1 ml of PMMA was used and in group C (control group) 0.3 ml saline was used. Twenty-four hours after the injection, the animals were sacrificed. Four tissue samples were obtained from the sites at 1 mm , 5 mm, 10 mm and 15 mm away from the PMMA mass in each rabbit of group A and group B , while four tissue samples were collected from different four sites from the tumor ’s center to border in each rabbit of group C. TdT-mediated dUTP nick-end labeling (TUNEL) method was used to determine the tumor cell apoptosis rate. Results After successful establishment of rabbit model, injection of PMMA was performed in sixteen among the eighteen rabbits. Technical success rates were 83.3% in both group A and B, and the success rate was 100% in group C. The difference in technical success rate was not significant. The mean tumor cell apoptosis rates of spinal VX2 carcinoma at 1 mm, 5 mm and 10 mm away from the PMMA mass in group A were (65.75±18.81)%, (50.00±14.24)% and(14.95±8.98)% respectively. The mean apoptosis rate in the control group was (9.79 ±5.24)%; the differences between the group A and the control group were statistically significant (P<0.05). The mean tumor cell apoptosis rate of spinal VX2 carcinoma at 15 mm away from the PMMA mass in group A was (10.30 ±8.13)%, which was not significantly different with that of the control group. The mean tumor cell apoptosis rates of spinal VX2 carcinoma at 1 mm and 5 mm away from the PMMA mass in group B were (49.20±15.57)% and(17.75±9.28)% respectively, which was significantly different with that of the control group(P<0.05); the mean tumor cell apoptosis rates at 10 mm and 15 mm away from the PMMA mass in group B were not significantly different with those of the control group. Statistically significant differences in the mean tumor cell apoptosis rates determined at 1 mm, 5 mm and 10 mm away from the PMMA mass existed between group A and group B(P<0.001). Conclusion PMMA can promote the apoptosis of tumor cells, properly increasing the injected amount of PMMA can enlarge the extent of tumor cell apoptosis.

OBJECTIVESince HFMD was designated as a class C communicable disease in May 2008, 18 months surveillance data have been accumulated to December 2009. This article was to describe the distribution of HFMD for age, sex, area, and time between 2008 and 2009, to reveal the characteristics of the epidemic.

METHODSWe analyzed weekly reported cases of HFMD from May 2008 to December 2009, and presented data on the distribution of age, sex, area and time. A discrete Poisson model was used to detect spatial-temporal clusters of HFMD.

RESULTSMore than 1 065 000 cases of HFMD were reported in Mainland China from May 2008 to December 2009 (total incidence: 12.47 per 10 000). Male incidence was higher than female for all ages and 91.9% of patients were <5 years old. The incidence was highest in Beijing, Shanghai, Zhejiang and Hainan. The highest peak of HFMD cases was in April and the number of cases remained high from April to August. The spatial-temporal distribution detected four clusters.

CONCLUSIONChildren <5 years old were susceptible to HFMD and we should be aware of their vulnerability. The incidence was higher in urban than rural areas, and an annual pandemic usually starts in April.

Aging ; Child, Preschool ; China ; epidemiology ; Cluster Analysis ; Female ; Hand, Foot and Mouth Disease ; epidemiology ; Humans ; Incidence ; Infant ; Male ; Sex Characteristics ; Time Factors

Objective:To analyze the incidence and epidemiological characteristics of traumatic spinal cord injury in China in 2018.Methods:Multi-stage stratified cluster sampling was used to randomly select hospitals capable of treating patients with spinal cord injury from 3 regions，9 provinces and 27 cities in China to retrospectively investigate eligible patients with traumatic spinal cord injury admitted in 2018. National and regional incidence rates were calculated. The data of cause of injury，injury level，severity of injury，segment and type of fracture，complications，death and other data were collected by medical record questionnaire，and analyzed according to geographical region，age and gender.Results:Medical records of 4，134 patients were included in this study，with a male-to-female ratio of 2.99∶1. The incidence of traumatic spinal cord injury in China in 2018 was 50.484 / 1 million （95% CI 50.122-50.846）. The highest incidence in the Eastern region was 53.791 / 1 million （95% CI 53.217-54.365）. In the whole country，the main causes of injury were high falls （29.58%），as well as in the Western region （40.68%），while the main causes of injury in the Eastern and Central regions were traffic injuries （31.22%，30.10%）. The main injury level was cervical spinal cord in the whole country （64.49%），and the proportion of cervical spinal cord injury in the Central region was the highest （74.68%），and the proportion of lumbosacral spinal cord injury in the Western region was the highest （32.30%）. The highest proportion of degree of injury was incomplete quadriplegia （55.20%），and the distribution pattern was the same in each region. A total of 65.87% of the patients were complicated with fracture or dislocation，77.95% in the Western region and only 54.77% in the Central region. In the whole country，the head was the main combined injury （37.87%），as well as in the Eastern and Central regions，while the proportion of chest combined injury in the Western region was the highest （38.57%）. A total of 32.90% of the patients were complicated with respiratory complications. There were 23 patients （0.56%） died in hospital，of which 17（73.91%） died of respiratory dysfunction. Conclusions:The Eastern region of China has a high incidence of traumatic spinal cord injury. Other epidemiological features include high fall as the main cause of injury cervical spinal cord injury as the main injury level，incomplete quadriplegia as the main degree of injury，head as the main combined injury，and respiratory complications as the main complication.

ObjectiveTo investigate primary and secondary transfer of exfoliated cells from human hands on non-porous substrates such as plastic steering wheel or computer mouse. MethodsDNA detection sensitivity and detection limit for mixed DNA profiling were examined to understand our laboratory’s ability to test for trace DNA. Forensic swabs were used to collect samples from volunteers’ one-hour-long unwashed hands， substrates touched by volunteers’ dominant hand 30 min after hand washing， substrates touched by volunteers 30 min after washing their hands and then immediately or 30 min following shaking hands， and individual A’s daily-use substrates touched by individual B and then by individual A again. Simulations were conducted to assess the potential for introduction of another person’s exfoliated cells from hands into routine casework samples. ResultsOur laboratory can obtain a full DNA profile from as little as 0.020 ng of DNA and detect minor components in a 1：9 mixed DNA sample. 85% of samples from unwashed hands yielded a full DNA profile. Primary transfer of a full DNA profile was found in 77% of substrates touched by volunteers’ dominant hand 30 min after hand washing， allowing differentiation between good and poor shedders， with no significant difference in genders and substrate types. 75% of substrates touched 30 min after hand washing and then immediately following handshaking yielded the other individual’s DNA profile （secondary transfer）， with the number of short tandem repeat （STR） loci detected ranging from 0 to 23； the percentage and number decreased substantially when the substrates were touched 30 minutes later. No foreign DNA was detected in routine casework samples with introduced exfoliated cells from hands. When two individuals took turns touching items with their hands， the major contributor to the DNA profile was not always the individual who made the last contact. ConclusionsPrimary and secondary DNA transfer can be detected on non-porous substrates， and based on the deposit of hand exfoliated cells， individuals can be categorized as good or poor shedders， which is an important factor affecting detection of DNA transfer. Besides considering the laboratory’s DNA detection sensitivity， if DNA is detected on substrates by hand contact， we need to take into account the potential for secondary transfer at different levels of activity when interpreting the results.