Type III secretory protein SINC of Chlamydia psittaci promotes host cell autophagy by activating the MAPK/ERK signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effects of SINC, a secreted protein of Chlamydia psittaci, on autophagy of host cells and the role of MAPK/ERK signaling pathway in mediating SINC-induced autophagy.@*METHODS@#RAW 264.7 cells treated with recombinant SINC were examined for changes in expression levels of LC3-II, Beclin-1, phosphorylated and total ERK1/2 using Western blotting. The expression level of LC3 in the treated cells was detected using immunofluorescence analysis, and the formation of autophagosomes and autolysosomes was observed with transmission electron microscopy (TEM). The effect of pretreatment with U0126 (a specific ERK inhibitor) on the expression levels of LC3-II and Beclin-1 in RAW 264.7 cells exposed to different concentrations of SINC was examined using Western blotting, and LC3 puncta in the cells was detected with immunofluorescence analysis.@*RESULTS@#The expression levels of LC3-II and Beclin-1 were the highest in RAW 264.7 cells treated with 2 μg/mL SINC for 12h. Immunofluorescence analysis showed exposure to SINC significantly increased the number of cells containing LC3 puncta, where the presence of autophagosomes and autolysosomes was detected. Exposure to 2 μg/mL SINC for 15 min resulted in the most significant increase of the ratios of p-ERK1/2/ERK1/2 in RAW 264.7 cells. Pretreatment of the cells with U0126 prior to SINC exposure significantly decreased the ratio of p-ERK1/2/ERK1/2, lowered the expression levels of LC3-II and Beclin-1, and decreased LC3 aggregation in the cells.@*CONCLUSIONS@#SINC exposure can induce autophagy in RAW 264.7 cells by activating the MAPK/ERK signaling pathway.

Association between early-life factors and pubertal timing in girls / 中国当代儿科杂志

OBJECTIVES@#To study the association between early-life factors (including birth weight, method of birth, gestational age, and history of gestational metabolic disorders) and pubertal timing in girls.@*METHODS@#The stratified cluster sampling method was used to select the girls in grades 2-3 and 7-8 from three primary schools and three middle schools in Guangzhou, China from March to December, 2019, and breast development was examined for all girls. A questionnaire survey was performed to collect the information on early-life factors. The multivariate logistic regression model was used to evaluate the association of gestational metabolic disorders, birth weight, method of birth, and gestational age with pubertal timing in girls. The Bootstrap method was used to assess the mediation effect of body mass index (BMI) (Z score) between high birth weight (≥4 000 g) and pubertal timing.@*RESULTS@#A total of 1 665 girls were enrolled, among whom 280 (16.82%) were judged to have early pubertal timing. The multivariate logistic regression analysis showed that high birth weight was associated with the increased risk of early pubertal timing (OR=2.12, 95%CI: 1.19-3.66, P=0.008). Nevertheless, no significant association was observed between other early-life factors and pubertal timing (P>0.05). The OR for the mediation effect of BMI (Z score) between high birth weight and early pubertal timing was 1.25 (95%CI: 1.09-1.47), accounting for 29.33% of the total effect of high birth weight on early pubertal timing.@*CONCLUSIONS@#High birth weight is associated with the increased risk of early pubertal timing in girls, and overweight/obesity may play a partial mediating role in the association between high birth weight and early pubertal timing in girls.

Comparison on Performance of Quantitative Ultrasound and Dual-Energy X-ray Absorptiometry in Evaluating Bone Health of Adults Aged 18-40 Years / 中国医学科学院学报

Objective To compare the consistency of quantitative ultrasound(QUS)and dual-energy X-ray absorptiometry(DXA)in measuring bone mineral density(BMD)of adults aged 18-40 years in Guangzhou and evaluate the diagnostic value of QUS for identifying low bone mass.Methods DXA was employed to measure the BMD and QUS to measure the speed of sound(SOS)in 731 participants.The Bland-Altman analysis was performed to evaluate the consistency of Z scores between SOS and BMD.With the BMD Z ≤-2.00 as the diagnostic criterion for low bone mass,the receiver operating characteristics curve of QUS was established,and the area under the curve(AUC)and the sensitivity,specificity,and correct diagnostic index for the optimal cut-off of SOS Z score were calculated.Results The results of Bland-Altman analysis showed that the mean differences in the Z scores of SOS and BMD in males and females were 1.27(-0.94 to 3.47)and 0.93(-1.33 to 3.18),respectively.The AUC of SOS Z score in the diagnosis of low bone mass in males and females was 0.734(95%CI=0.380-0.788)and 0.679(95%CI=0.625-0.732),respectively.In males,the optimal cut-off of SOS Z score for low bone mass was -0.35,with the sensitivity,specificity,and correct diagnostic index of 64.1%,68.6%,and 0.327,respectively.In females,the optimal cut-off value of SOS Z scores for low bone mass was -1.14,with the sensitivity,specificity,and correct index of 73.9%,54.8%,and 0.285,respectively.Conclusion QUS and DXA show poor consistency in the diagnosis of BMD in the adults aged 18-40 years in Guangzhou,while QUS demonstrates an acceptable value in identifying low bone mass.

Association Between Dietary Knowledge and Food Preferences in Residents Aged 18 and Over in China Based on Latent Class Analysis / 中国医学科学院学报

Objective To investigate the food preferences and explore the potential association between dietary knowledge and food preferences in residents aged 18 and over in China,so as to provide a basis for promoting healthy diets.Methods The latent class analysis was carried out with the 2015 cross-sectional data of China health and nutrition survey to categorize the food preferences among 8 783 residents aged 18 and over.Multinomial Logistic regression was adopted to assess the association between and dietary knowledge and food preferences.Results The food preferences of the residents aged 18 and over in China were classified into preference for less vegetable(3.28%),lack of preference(11.20%),diverse preferences(4.19%),and preference for healthy diets(81.33%).The proportion of the adults with dietary knowledge was 36.87%(3 238/8 783).The dietary knowledge varied in the adults with different food preferences(all P<0.001).After adjusting for gender,age,urban and rural distribution,education background,and annual household income,for each point increase in the dietary knowledge score,there was an estimated reduction of 22% in the probability of preferring less vegetables(OR=0.78,95%CI=0.76-0.80, P<0.001),13% in the probability of lacking preference(OR=0.87,95%CI=0.86-0.89, P<0.001),and 3% in the probability of having diverse preferences(OR=0.97,95%CI=0.94-1.00, P=0.030).Compared with those lacking dietary knowledge,the individuals with dietary knowledge had a 77% less probability of preferring less vegetables(OR=0.23,95%CI=0.16-0.32, P<0.001),a 55% less probability of lacking preference(OR=0.45,95%CI=0.39-0.53, P<0.001),and a 23% less probability of having diverse preferences(OR=0.77,95%CI=0.61-0.96, P=0.023).Conclusions The residents aged 18 and over in China presented four food preferences,including preference for less vegetables,lack of preference,diverse preferences,and preference for healthy diets,the last of which had the highest proportion.The individuals with lower levels of dietary knowledge have higher probability of preferring unhealthy food.

Effect of Guiqi Baizhu Prescription Combined with Oxaliplatin on Expression of EGFR and VEGFR2 and Angiogenesis in Gastric Cancer-bearing Mice / 中国实验方剂学杂志

ObjectiveTo investigate the effect of Guiqi Baizhu prescription （GQBZ） combined with oxaliplatin on the expression of epidermal growth factor receptor （EGFR） and vascular endothelial growth factor receptor-2 （VEGFR2） and angiogenesis in gastric cancer-bearing mice. MethodThe tumor-bearing model of gastric cancer was induced in Kunming mice. The mice were randomly divided into blank group， model group， oxaliplatin group （10 mg·kg-1）， and high- （17.68 g·kg-1）， medium- （8.84 g·kg-1）， and low-dose （4.42 g·kg-1） combination groups （GQBZ combined with oxaliplatin）. After the last administration， the transplanted tumor was collected and the tumor inhibition rate was calculated. Hematoxylin-eosin （HE） staining was used to observe the morphological changes of tumor tissues. Enzyme-linked immunosorbent assay （ELISA） was used to detect the serum content of epidermal growth factor （EGF）， interleukin-8 （IL-8）， and vascular endothelial growth factor （VEGF）. Western blot and immunohistochemistry （IHC） were used to detect the expression of EGFR， phosphorylated EGFR （p-EGFR）， VEGFR2， phosphorylated VEGFR2 （p-VEGFR2）， and platelet-endothelial cell adhesion molecule （CD31）. Real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of EGFR and VEGFR2. ResultThe tumor weight in the drug intervention groups was significantly lower than that in the model group （P<0.01）. Compared with the oxaliplatin group， the high- and medium-dose combination groups showed reduced tumor weight （P<0.05， P<0.01）. The tumor cells in the model groups were high in cell density and regular in shape， and no clear tissue necrosis was seen. The tumor cell density in the drug intervention groups was reduced， and clear tissue necrosis and large-scale inflammatory cells were visible. Compared with the blank group， the model group and the drug intervention groups showed increased serum levels of EGF， VEGF， and IL-8 （P<0.05， P<0.01）. Compared with the model group， the drug intervention groups showed decreased serum levels of EGF， VEGF， and IL-8 （P<0.01）， reduced protein expression of EGFR， p-EGFR， VEGFR2， p-VEGFR2， and CD31， and declining mRNA expression of EGFR and VEGFR （P<0.01）. Compared with the oxaliplatin group， the high- and medium-dose combination groups showed decreased serum levels of EGF， VEGF， and IL-8 （P<0.05， P<0.01）， reduced protein expression of EGFR， p-EGFR， VEGFR2， p-VEGFR2， and CD31， and dwindled mRNA expression of EGFR and VEGFR2 （P<0.05， P<0.01）. The low-dose combination group showed decreased serum levels of EGF， VEGF， and IL-8， reduced protein expression of EGFR， p-EGFR， VEGFR2， p-VEGFR2， and CD31， and dwindled mRNA expression of EGFR and VEGFR2， but the difference was not statistically significant. ConclusionGQBZ combined with oxaliplatin can inhibit the growth and angiogenesis of tumor tissues in gastric cancer-bearing mice by affecting the expression of EGFR and VEGFR2.

Preliminary investigation on the dynamic change in epidermal stem cells under mechanical stress in vivo / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the distribution of epidermal stem cell (ESC) after soft tissue expansion, and to explore dynamic change in ESC under mechanical stress and kinetic mechanism of skin expansion.</p><p><b>METHODS</b>Skin samples were collected from patients after expansion of the scalp. They were divided into three groups: A group (scalp harvested 3 cm away from the center of dilator), B group (scalp tissues at the edge of dilator), and control group (scalp without dilatation). The tissue structures were observed with optical microscope with HE staining. The distribution and differentiation characteristics of cell keratin 19 (CK19) positive cells were observed with inverted phase contrast microscope after immunohistochemistry staining.</p><p><b>RESULTS</b>HE staining showed that the epidermis was thickened and distributed densely with uneven, rugged and increased layers in A, B groups. With immunohistochemistry staining, CK19 positive cells appeared in multilayers in basal membrane, a few of them were in cluster or dispersed , with" hollowing" structure formation. These phenomena were not seen in control group.</p><p><b>CONCLUSION</b>ESC can proliferate with abnormal distribution and "hollowing" structure formation after mechanical dilatation, which may be related to dynamic changes in basal layer cells.</p>