Objective To discuss the value of high resolution MRI in the evaluation of small intralabyrinthine lesions with the symptom of vertigo. Methods We retrospectively analyzed the imaging examination techniques and imaging finding of 13 cases of labyrinthine hemorrhage or exudate and 6 cases of intralabyrinthine schwannoma (ILS) with the symptom of vertigo. Two cases of labyrinthine hemorrhage or exudate and 3 cases of ILS underwent temporal bone high resolution CT(HRCT) scan and all the 19 patients received highresolution MR examination. Patients of labyrinthine hemorrhage or exudate received fluid?attenuated inversion recovery (FLAIR)T2WI in addition to routine pre?contrast temporal bone MR. Pre?and post?contrast MR of the temporal bone were performed on the ILS patients. In particular, 3 ILS cases received three?dimensional sampling perfection with application?optimized contrasts by using different flip angle evolutions (3D?SPACE) sequence. Results There was no abnormal finding on HRCT of the inner ear of the 2 labyrinthine hemorrhage cases. On T1WI, regions of mild increased signal intensity of the labyrinth of affected side could be spotted in 7 patients whereas no abnormal signal intensity was found in the other 6 patients. On T2WI, all the 13 labyrinthine hemorrhage or exudate cases had no abnormal finding in the inner ear. On FLAIR T2WI sequence, regions of increased signal intensity of the labyrinth of affected side could be found in all the 13 cases. Thress ILS patients that received HRCT scan showed no valuable finding. On T1WI, no abnormal signal intensity was found in the labyrinth of the 6 patients. On T2WI, regions of decreased signal intensity of the labyrinth could be found in only 3 patients. All the 3 cases that received 3D?SPACE sequence appeared as a filling defect in the high?signal labyrinth clearly while 2 of the 3 lesions could not be found on T2WI. After Gadolinium administration, all the 6 ILSs were obviously enhancing. Conclusions High resolution MRI is valuable in the diagnosis of labyrinthine hemorrhage or exudate and ILS. The use of FLAIR T2WI sequence can help us to find labyrinthine hemorrhage or exudate more sensitively. The use of 3D?SPACE sequence can help us to detect and diagnose small intralabyrinthine lesions.

Objective To study the dosimetry parameters of 125I seed source (type Sinko BT-125-1) with thermoluminescent dosimeter (TLD) in the phantom.Methods The new type of phantom was modified to suit to measurement of a common type of 125I seed source.The AAPM TG43 protocol recommended measurements of dose-rate constant (Λ),radial dose function (gL (r)),and anisotropy function (F (r,θ)) have been performed in the phantom with TLD.Results The Λ was 0.928 cGyh-1 U-1.The gL(r) was determined at different radial distances r ranging from 1.0 to 10.0 cm with an interval of 1.0 cm ; and F (r,θ) at angles from 0° to 90° in 10° increments.The gL (r) of 125I seed source showed a difference of 9.6％ at the most in comparison to the corresponding values of 125I seed source (type Amersham 6711).The difference in F(2 cm,θ) of 125I seed source and Amersham 6711 was up to 10.2％ near the source end.With the phantom the combined standard uncertainty in the whole measurement was less than 6.0％.Conclusions The experimental results exhibit fairly small measurement uncertainties and good self-consistency.It's feasible to measure the dosimetry characters of permanent implant seeds in the modified phantom.

Objective: To explore differences in the detection rate of elevated blood pressure (BP) in children aged 6-8 years old, and to verify the apparent existence of white-coat hypertension (BP) in children. Methods: Based on census data(PROC), and three subsequent BP readings were taken during follow-ups which were carried out from October 2018 to June 2019. A total of 1 785 children were included in the present study. Using updating blood pressure reference for Chinese children aged 3-17 years, compared the BP detection rate at baseline, at the first follow-up, and the average value of the last two BP readings. Fluctuations in the detection rate of elevated BP in children at different time-points were analyzed. Results: The detection rates of the three elevated BP measurements of 6-8-year-old children were 57.65%, 25.88% and 15.46%, respectively, and the detection rate was higher among boys than girls. The detection rate of baseline BP was higher than that of the first follow-up BP measurements and the average of the last two BP measurements(P<0.01). Given the agreement in the diagnosis of high SBP, high DBP, high BP at baseline, and the average of the last two follow-up BP measurements, elevated BP at baseline was the lowest among the three groups and SBP was higher than DBP. Conclusion Blood Pressure fluctuations might be caused by transient tension that was experienced during the baseline BP measurement and during the first of the three follow-ups. Therefore, the average value of last two BP measurements may better reflect the real BP level in children.

Objective: To examine the association between the visceral adiposity index (VAI) and nonalcoholic fatty liver disease (NAFLD) in the pediatric population in order to improve risk stratification and prevention systems for chronic liver disease. Methods: A total of 510 overweight/obese children aged 6-8 years old were enrolled from the child cohort which was designed to study puberty, obesity, and cardiovascular risk (PROC), and complete data from liver ultrasounds and the VAI were obtained. Used Spearman s rank correlation coefficient, Chi-square tests, and Logistic regression analyses to explore the association between the VAI and NAFLD. Results: The detection rates of NAFLD for boys and girls were 25.9% and 11.1%, respectively. VAI for normal group and the NAFLD group were 0.43(0.31, 0.61) and 0.61(0.44, 0.87) in boys, and 0.74(0.56, 1.07) and 1.08(0.67, 1.51) in girls, respectively. Spearman s correlation coefficient analysis showed that triglycerides(TG), VAI, and the third quintile VAI group were positively correlated with NAFLD in both boys and girls(r=0.19,0.26,0.29;0.16,0.16,1.18,P<0.05), and high-density lipoprotein-cholesterol (HDL-C) was negatively correlated with NAFLD in boys (r=-0.21, P<0.05). With advancing tertiles of VAI, the increasing trend in the NAFLD detection rate was statistically significant in boys and girls(Chi-square for trend were 21.77,7.66, P<0.01). The results of univariate and multivariable Logistic regression showed that, by taking the first tertile of VAI as a reference, the risk of NAFLD among boys was higher in the second tertile (cOR=2.59, 95%CI=1.15-5.86; aOR=2.33, 95%CI=1.01-5.36) and in the third tertile(cOR=5.73, 95%CI=2.62-12.53; aOR=4.87, 95%CI=2.15-11.03), where as the risk among girls was higher in the third tertile(cOR=4.43, 95%CI=1.40-14.00). Conclusion VAI is positively correlated with pediatric NAFLD. Higher tertiles of VAI were associated with an increased risk of NAFLD in overweight and obese children, which indicates that VAI can be used as an early predictor of NAFLD.

Objective:To explore the changes of disease burden and risk factors of chronic kidney disease (CKD) due to type 1 and type 2 diabetes mellitus in China from 1990 to 2019, and to provide reference data for the prevention and control of diabetic kidney disease (DKD).Methods:The Chinese DKD data were obtained from the 2019 Global Burden of Disease (GBD) database. The morbidity, prevalence, mortality, years lived with disability (YLD), years of life lost (YLL), and disability-adjusted life year (DALY) were used to compare the disease burden of CKD due to type 1 and type 2 diabetes mellitus from 1990 to 2019. In addition, the risk factors of DKD were analyzed.Results:The numbers of CKD patients due to type 1 and type 2 diabetes mellitus in China were 574 (95% UI 495-665) and 31 076 (95% UI 28 152-33 909) thousand, and the numbers of new cases were 9 (95% UI 8-11) and 434 (95% UI 390-481) thousand in 2019, respectively. The numbers of death were 13 (95% UI 8-18) and 63 (95% UI 50-77) thousand, respectively. The age groups with the largest number of patients and new cases of CKD due to type 1 diabetes mellitus were 30-34 years old and <5 years old, respectively. The age group with the largest number of patients and new cases of CKD due to type 2 diabetes mellitus were 50-54 years old and 70-74 years old, respectively. From 1990 to 2019, the age-standardized prevalence rate of DKD patients in China was relatively stable, but the age-standardized incidence rate and YLD rate showed an upward trend, while the age-standardized mortality rate, YLL rate, and DALY rate showed a downward trend. The main risk factors associated with DKD death were high fasting plasma glucose, kidney dysfunction, high systolic blood pressure, high body mass index, high sodium diet, and lead exposure. The proportions of DKD death caused by high systolic blood pressure and high body mass index in the Chinese population were still increasing. Conclusions:From 1990 to 2019, the age-standardized incidence and YLD rate of DKD in China shows an upward trend, while the age-standardized prevalence rate is relatively stable, and the age-standardized mortality rate, YLL rate, and DALY rate show a decreasing trend. High fasting glucose, renal failure, high systolic blood pressure, high body mass index, high sodium diet, and lead exposure are risk factors associated with death in DKD patients. With the progress of aging, the disease burden of DKD in China will continuously increase. Future work should be focused on population-specific interventions, taking into consideration the risk factors identified within the study.

Objective: To identify the association of carotid intima-media thickness (cIMT) and visceral fat area (VFA) to inform prevention of cardiovascular disease in later life. Methods: All the grade one students of six non-boarding primary schools in Shunyi District, Beijing were enrolled, based on population-based survey design, to establish the child cohort on sensitization, puberty, obesity and cardiovascular risk (PROC). Socio-demographic information survey and anthropometric measure, blood and urine test were carried out. Robust linear regression was used to determine the relationship between cIMT and other factors. Results: Among 1 711 participants, a significant difference were observed between normal, overweight and obesity children on cIMT [(0.35±0.02)(0.36±0.02)(0.37±0.03)mm] (F=41.4, P<0.01) and VFA [16.2(13.6-19.3), 22.7(18.6-27.3), 51.5(33.9-73.0)cm2] (χ2=854.5, P<0.01). After adjusting age and sex, univariate robust linear regression showed that cIMT was associated with height, SBP, DBP, HDL-C, VFA (P<0.05) and TG (P=0.055). Multivariable robust linear regression indicated that in total and boys only included models, cIMT was associated with VFA and SBP(β=0.000 2, 0.000 2, 0.000 2, 0.000 2, P<0.05); while in girls only included model cIMT was associated with VFA and TG (β=0.000 2, 0.006 2, P<0.05). Conclusion VFA is stable to predict the increase of cIMT in children. We can use VFA to simplify the classification management of children and inform targeted early prevention of cardiovascular disease in adulthood.

Objective: The study aimed to explore sex differences in the growth and physical development of Beijing school-aged children and adolescents. Methods: Data obtained from regular health examinations of 94 122 school-aged children and adolescents aged 6-18 years old were collected from primary and high schools in Shunyi District from 2009 to 2018, and a longitudinal dataset was compiled with complete anthropometric parameters including height, weight, and BMI levels after linkage of individuallevel information. The age-specific growth rate was calculated and a linear mixed-effects model was used to identify sex differences according to chronological or relative age to peak height velocity (PHA). Results: Height, weight, and BMI levels increased with age in both boys and girls. Girls were taller than boys in the 10-11 year-old age group, catch-up growth in height was observed in boys at age 12, whose height surpassed that of girls thereafter. Boys had a higher weight and BMI than girls in all age groups (P<0.01). Sex differences were found in the growth rates of height, weight, and BMI levels(t=-67.56，-47.46，3.22，P<0.01), which was demonstrated by the interaction effect of sex and age in the linear mixed-effects model. The PHA in boys was 12 years old, which was two years later than the PHA in girls. Boys reached peak weight velocity at 12 years old, lagging one year behind girls who reached their peak at 11 years old. The curves of the BMI growth rate with age showed double peaks in boys and the first peak appeared at 10 years, which was one year earlier than girls. The change in weight was highly synchronized in time with the increase in height, after adjusting for the growth rate of weight by PHA. Weight velocity increased with age before the onset of puberty until PHA, and then it declined; boys presented with obvious fat accumulation before the onset of puberty. Conclusion Sex differences in the growth and physical development of school-aged children and adolescents were persistent and apparent, and the change in weight was highly synchronized in time with the increase in height.

Objective: To explore sex differences between weight and systolic blood pressure (SBP) changes among school-age children and adolescents in Beijing, and to provide a basis for priority intervention to control the rapid growth of body weight and blood pressure. Methods: Anthropometric measurement data of 70 288 children and adolescents from primary and high schools in Shunyi District were collected from 2009 to 2018, and a longitudinal dataset with complete data related to weight and BP after individual data linkage was compiled. The age-specific weight and SBP growth rates were calculated, and a linear mixed-effects model was used to identify sex differences in chronological growth rates. Results: Weight and SBP increased with age in both boys and girls, and the mean weight and SBP were higher in boys than in girls across all age groups. The result of the linear mixed-effects model indicated apparent sex differences in weight and SBP growth rates, with an age and sex interaction term(β=-0.35, -0.40, P<0.01). The age at peak weight velocity (PWA) was 12 years old and the age at peak SBP velocity was 13 years old in boys, which occurred one and three years later than for girls, respectively. In addition, the peak weight and SBP velocity were higher in boys than in girls. The curves of the SBP growth rate adjusted for the PWA, showed that the peak SBP velocity occurred two years before PWA and the second peak SBP velocity occurred at the PWA, which indicated "double peaks" in both boys and girls. The SBP growth rate was always higher in boys than in girls, and the rates declined after PWA. Conclusion Sex differences in weight and SBP growth rates were persistent and obvious in school-age children and adolescents in Beijing and the change in SBP was highly time synchronized with the increase in weight.

OBJECTIVETo detect mutation of GPR143 gene in a Chinese patient affected with ocular albinism.

METHODSPeripheral blood samples were collected from the proband and his parents. The coding regions of the GPR143 gene were subjected to PCR amplification and Sanger sequencing.

RESULTSA previously unreported mutation (c.758T>A) was found in exon 6 of the GPR143 gene in the proband and his mother. The same mutation was not found in his father. As predicted, the mutation has resulted in a stop codon, causing premature termination of protein translation.

CONCLUSIONA novel mutation of the GPR143 gene related to X-linked ocular albinism has been identified.

Adult ; Albinism, Ocular ; genetics ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; Eye Proteins ; genetics ; Female ; Genetic Diseases, X-Linked ; genetics ; Humans ; Infant ; Male ; Membrane Glycoproteins ; genetics ; Molecular Sequence Data ; Mutation

Objective To explore the correlations between intravoxel incoherent motion (IVIM) parameters measured at different time points and histopathological markers in an orthotopic xenograft hepatocellular carcinoma (HCC) nude mice model. Methods A total of 40 HCC orthotopic bearing mouse models were established. When they grew to 21 days, 10 HCC-bearing mice were randomly selected as the baseline group (Group A) by a numeric table method. Then the rest mice were randomly selected on the 28th day, 35th day, and 42nd day of the growth by using the same method, 10 each for B, C, and D groups, respectively. All mice underwent MR IVIM study and apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D*) and perfusion fraction (f) were measured. After the MRI scanning, the tumors were removed for pathological examination. The necrosis score (NF), tumor size and microvessel density (MVD) were calculated. The IVIM parameters were compared among these 4 groups by Kruskal-Wallis H test and the correlations between these IVIM parameters and histological features were studied with Spearman rank correlation test. Results One tumor in each of C and D groups was excluded because f values of IVIM were close to zero. There were significant differences found in ADC and D among all the 4 groups (P＜0.05). However, no difference was found in D*and f (P＞0.05). Compared with the baseline (group A), ADC decreased significantly at 7 and 14 days, whilst D decreased significantly at 7 days. The differences in tumor size, MVD and NF between the 4 groups were statistically significant. Compared with the baseline, the tumor size and NF significantly increased at 7, 14 and 21 days, and MVD increased at 14 and 21 days. Significantly positive correlations were demonstrated between ADC and MVD, NF (r=0.461 and 0.442, P＜0.05), between D and MVD, NF (r=0.568 and 0.519, P＜0.05) after exclusion of the data from the baseline. The parameter f from all the time points including the baseline was positively correlated with histological MVD and NF (r=0.590 and 0.458, P＜0.05). Conclusion IVIM parameters may reflect the intratumoral vascularity, tumor cell proliferation and necrosis of HCC, and they are correlated with the pathological indicators.