Objective:To investigate the effect of radiofrequency radiation (RF) from 5G mobile phone communication frequency bands (3.5 GHz and 4.9 GHz) on the permeability of the blood-brain barrier (BBB) in mice.Methods:A total of 24 healthy adult male C57BL/6 mice (6-8 weeks old) were randomly divided into Sham, 3.5 GHz RF and 4.9 GHz RF groups, and 8 mice in each group. Mice in the RF groups were systemically exposed to 5G cell phone radiation for consecutive 35 d(1 h/d) with 50 W/m 2 power density. The BBB permeability of mice was detected by Evans Blue (EB) fluorescence experiment. The expression levels of the BBB tight junction-related proteins (ZO-1, occludin and claudin-11) and the gap junction-related protein Connexin 43 were determined by Western blot. Results:The number of spots, fluorescence intensity and comprehensive score of EB were significantly increased in 3.5 GHz RF group and 4.9 GHz RF group compared with the Sham group ( t=12.98, 17.82, P<0.001). Compared with the Sham group, the content of S100B in mouse serum was significantly increased in 3.5 GHz RF group and 4.9 GHz RF group ( t=19.34, 14.68, P<0.001). The BBB permeability was increased in the RF group. The expression level of occludin protein was significantly reduced in the 3.5 GHz RF group ( t=-3.13, P<0.05), and this decrease was much profound in the 4.9 GHz RF group ( t=-6.55, P<0.01). But the protein levels of ZO-1, Claudin-11 and Connexin 43 in the cerebral cortex of the RF groups had no significantly difference in comparison with the Sham group( P>0.05). Conclusions:The continuous exposure of mobile phone RF at 3.5 GHz or 4.9 GHz for 35 d (1 h/d) induces an increase of BBB permeability in the mouse cerebral cortex, perhaps by reducing the expression of occludin protein.

Objective:To investigate the effect of thoracic X-ray irradiation on the spermatogenesis of adult male mice.Methods:A total of 24 healthy adult male C57BL/6 mice (6-8 weeks old) were randomly divided into radiation group (Radiation) and sham-radiation group (Sham), 12 mice in each group. The area of thoracic irradiation was 1.5 cm× 2 cm, and the dose rate was 3.04 Gy/min, 8 Gy/d for 3 consecutive days, 24 Gy in total. At 7 d and 21 d after thoracic irradiation, the bilateral testes and epididymal tails were stripped and the testicular index was calculated. The morphology of testis was examined by haematoxylin-eosin (HE) staining, then the diameter of seminiferous tubules and the thickness of seminiferous epithelium were measured. The sperms were collected from the bilateral epididymal tails for sperm counting. The level of apoptosis in testis and levels of apoptosis-related proteins were detected by TUNEL and Western blot, respectively.Results:Compared with Sham group, the morphology of testis and epididymis was seriously damaged, the diameter of seminiferous tubules significantly decreased at 21 d after irradiation ( t = 8.93, P < 0.05), and the seminiferous epithelium significantly decreased at 7 d and 21 d after irradiation ( t = 4.24, 12.77, P < 0.05). In addition, the number of sperms significantly decreased ( t = 4.30, 2.98, P < 0.05). The number of TUNEL positive cells in the seminiferous epithelium significantly increased at 7 d and 21 d after irradiation ( t = -2.73, -3.74, P < 0.05). Meanwhile, the level of cleaved Caspase-3 protein significantly increased at 7 d and 21 d after irradiation ( t = -2.96, -2.46, P < 0.05). The concentrations of SCF and GDNF did not change at 7 d after irradiation, but were significantly increased at 21 d after irradiation ( t = -10.46, -5.42, P < 0.05). Conclusions:The thoracic X-ray irradiation could lead to spermatogenesis disorder in male adult mice, and the induction of spermatogenic cell apoptosis and the secretory dysfunction of sertoli cells may be involved.

The pathogenesis and treatment strategies of acute myeloid leukemia (AML) are different for disparate gene mutations. Therefore, precise molecular testing plays a vital role in its diagnosis. However, when clinical laboratories perform molecular testing, internal quality control materials similar to clinical samples for molecular testing are lacking. At the same time, there is no related external quality assessment system to evaluate clinical laboratory test results. In order to improve the accuracy and credibility of molecular testing in clinical laboratories, we used the CRISPR/Cas9 technology to construct the DNMT3A (R882H, 2645G > A) HEK293T cell line for the quality control of AML molecular testing. We replaced the cas9 protein recognition site AGG in the ssODN with AGA to prevent the homologous recombination cell line from being cleaved by the cas9 protein again, thereby increasing the success rate of homologous recombination cell line production. It has been verified that the DNMT3A (R882H, 2645G > A) cell line can be inherited stably. The mutation frequency of the external quality assessment sample made by the DNA extraction of DNMT3A (R882H, 2645G > A) HEK293T cell line was very stable, tested by two Sanger sequencing instruments and three NGS instruments. The results above showed that the DNA extraction of DNMT3A (R882H, 2645G > A) HEK293T cell line can not only be used as internal quality control, but also be used as external quality assurance samples for monitoring different manufacturers and platforms, thereby improving the accuracy and credibility of molecular testing in clinical laboratories.

Objective To clarify the effects of 5G mobile phone radiofrequency radiation exposure on male mouse fertility and to preliminarily explore the underlying mechanisms. Methods Healthy male C57BL/6 mice aged 7-8 weeks were randomly assigned to Sham group, 3.5 GHz radiofrequency radiation group, and 4.9 GHz radiofrequency radiation group, with 16 mice in each group. The mice were exposed to 3.5 GHz or 4.9 GHz mobile phone radiofrequency radiation for 42 consecutive days (1 h per day). The sperm quality was evaluated using sperm count, deformity rate, and motility. H&E staining was performed to assess testicular tissue structure by observing the morphology of spermatogenic cells at various development stages, the diameter of seminiferous tubules, and the thickness of seminiferous epithelium. The sperm mitochondrial function was assessed using sperm mitochondrial membrane potential and testicular ATP content. The fertility of mice was evaluated through fertility rate, litter size, and survival rate of offspring. The underlying mechanisms were explored by detecting the methylation of LRGUK gene and its mRNA and protein levels. Results Compared with the Sham group, there were no significant changes in sperm count in the 3.5 GHz and 4.9 GHz groups; however, the sperm abnormality rate significantly increased (P < 0.05) and sperm motility significantly decreased (P < 0.05). The structure of testicular tissue, the function of sperm mitochondria, and fertility of mice showed no significant changes as compared with the Sham group. The methylation level of LRGUK gene in the testes significantly increased, while the mRNA and protein expression levels significantly decreased. Conclusion Exposure to 3.5 GHz and 4.9 GHz mobile phone radiofrequency radiation for 42 consecutive days can lead to an increase in sperm deformity rate and a decrease in sperm motility in mice, but has no significant effect on fertility, which may be related to an increase in methylation level of the LRGUK gene in the testes.

Iron deficiency anemia is one of the most prevalent nutritional deficiency worldwide. The commonly used cut-off values for identifying iron deficiency are extrapolated from older children and may not be suitable for infants. Therefore, our study aimed to establish appropriate cut-off values for the evaluation of iron status in Chinese infants. Pregnant women who delivered at ⋝37 gestational weeks with normal iron status were recruited. Later, infants with normal birth weight and who were breastfed in the first 4 months were selected. Blood samples were collected to assess hemoglobin, serum ferritin, soluble transferrin receptor, mean corpuscular volume and free erythrocyte protoporphyrin. Cut-offs of all iron indices were determined as the limit of 95% confidence interval.
Anemia, Iron-Deficiency ; blood ; diagnosis ; Breast Feeding ; China ; Humans ; Infant ; Reference Values

OBJECTIVETo investigate the current enteral feeding practices in hospitalized late preterm infants in the Beijing area of China.

METHODSA multi-center, cross-sectional study was conducted. Infants born after 34 weeks and before 37 weeks of gestation were enrolled from 25 hospitals in the Beijing area of China from October 2015 to October 2017. Data on enteral feeding practices were collected and analyzed.

RESULTSA total of 1,463 late preterm infants were enrolled, with a mean gestational age (GA) of 35.6 (34.9, 36.1) weeks. The percentage of exclusive breastfeeding was 4.5% at the initiation of enteral feeding but increased to 14.4% at discharge. When human milk was not available, most infants (46.1%) were fed with preterm infant formula. The rate of exclusive human milk feeding in infants born at 34 weeks gestation was higher than at discharge (21.1% of infants born at 34 weeks' GA versus 12.1% of infants born at 35 weeks' GA versus 12.3% of infants born at 36 weeks' GA, P < 0.001). Only 28.4% of late preterm infants achieved full enteral feeding at discharge, and only 19.2% achieved 120 kcal/(kg•d) by enteral feeding at discharge. Importantly, 40.5% of infants did not regain the birth weight at discharge.

CONCLUSIONEnteral feeding support of late preterm infants has not been standardized to achieve optimal growth. Moreover, the human milk feeding rate was low, and many late preterm infants did not achieve the goal of enteral feeding and failed to regain birth weight at the time of discharge. More aggressive enteral feedings protocols are needed to promote human milk feeding and optimize growth for late preterm infants.

Breast Feeding ; China ; Cross-Sectional Studies ; Enteral Nutrition ; Female ; Gestational Age ; Humans ; Infant Formula ; Infant, Newborn ; Infant, Premature ; Male ; Milk, Human

OBJECTIVE: To evaluate the necessity and suitability of the anti-HCV ELISA teot gray zone setted up by 7 blood station laboratories. METHODS: 7 blood station laboratories were coded as 1, 2, 3, 4, 5, 6 and 7 respectively; 8 kinds of ELISA reagents were coded as A, B, C, D, E, F, G and H respectively. 1 or 2 of 8 ELISA reagents produced by different manufactories were used to detect the anti-HCV in specimens of same group by 7 blood station laboratories; the Westen blot was used to detect the specimens with difference of detected results so as to difine the serological status of specimens. The true positive rate of specimens detected by laboratories and gray zone-comfirined positive rate of specimens were accounted so as to analyze the necessity of setting up the gray zone for anti-HCV ELISA test of 7 blood station laboratories; the optimal cut-off value for anti-HCV ELISA test was determined in 7 blood station laborafories by ROC curve and the changes of sensitivity and specificity of 3 different cut-off value(laboratory work cut-off value, manifactory-recommended cun-off value and optimal cut-off value) were compared so as to analyze the suitability of gray zone for anti-HCV ELISA test in 7 blood station laboratories. RESULTS: The true positive rate detected by 7 blood station laboratories, out of which coded 1 laboratory used 2 kinds of coded A, B reagents was 95.40%(1A), 99.23% (1B), 94.25% (2C), 96.17% (3D), 98.08% (4E), 96.93% (5F), 97.32%(6G) and 93.10%(7H). Except for 2C(94.25%) and 7H(93.10%), the true positive rate detected by laboratoies which not sutted up gray zone, the gray zone-con-firmed positive rate in 6 blood station laboratories setted up gray zone: was 0.00%, 0.00%, 21.43%, 0.00%, 0.00%, 0.00% and 38.89%. The comparison of 3 different cut-off valuces by ROC curve showed that the anti-HCV cut-off values in 5 laboratories(1B, 2C, 4E, 5F and 6G) were as follows: optimal cut-off value＞manufactory recommeded cut-off value＞laboratory work cut-off value, thus use of manufactory-recommeded cut-off value abreadly has reached the high sensitivity requinements for laboratory screening; however, the optimal cut-off value in laboratories 1A, 3B and 7H, thas the appropriate gray zone should be used. In 6 laboratories setting up gray zone, the gensitivity in 3D, 7H laboratories only a little improved (1.60% and 2.70% raspectively) in Eamparison between laboratory work cut-off value and manufactorg-recommeded cut-off value; moreover, the sensitivity in other laboratories not is changed, but the specificity decreased (0.20%-0.50%). CONCLUSION In addition to setting up the appropriate gray zone in laboratories 1A, 3D and 5H, the gray zone in other laboratories may be cancelled. Even in the same laboratory, the setting up the gray zone also should be scientifically assessed, the same scale cannot be blindly used, thus appropniate strategies should be established.
Enzyme-Linked Immunosorbent Assay ; Hepatitis C ; Hepatitis C Antibodies ; Humans ; ROC Curve ; Sensitivity and Specificity