Wei sheng yan jiu = Journal of hygiene research最新文献

Objective: To study the effects of staple food on the glycemic responses through a controlled feeding trial.

Methods: In November 2020, two groups of volunteers with different staple food habits(the rice group, n=35, and the wheat group, n=35), were recruited from Changzhi Medical College in Shanxi Province. They were subjected to a two-stage feeding trial, in which their staple food habits were maintained in the first stage(staple food fortification period, 4 weeks) and then swapped in the second stage(staple food swap period, 4 weeks), while keeping the rest of the dietary components same. A continuous glucose monitoring system was used to monitor the glycemic response of glucose, steamed buns and steamed rice, equivalent to 50 g of available carbohydrate(CHO). Blood glucose level up to 120 minutes postprandial, incremental area under the curve(iAUC) and glycemic index(GI) were analyzed.

Results: During the staple food fortification period, the glycemic response to steamed buns at 15 min(5.43±0.69 vs.5.14±0.50 mmol/L, P=0.047), 30 min(6.63±0.98 vs.6.10±0.70 mmol/L, P=0.012), 45 min(6.81±1.15 vs.6.21±0.67 mmol/L, P=0.011) and 60 min postprandial(6.03±0.96 vs.5.56±0.59 mmol/L, P=0.017) in the rice group were higher than the wheat group, and the trends for blood glucose fluctuation during the 120 minutes after consuming steamed buns were different between the two groups. During the staple food swap period, the 120 min iAUC(83.24±30.15 vs.69.32±26.25 mmol·min/L, P=0.032) and GI(88±24 vs.75±33, P=0.041) of the rice group to steamed buns were higher than the wheat group. Comparing the differences between the two groups in the staple food exchange period and the staple food intensification period, the rice group had an increased glycemic response to steamed buns(P=0.007), while the wheat group had an increased glycemic response to glucose(P<0.001), steamed buns(P<0.001) and steamed rice(P=0.018). The 120 min iAUC of steamed buns in the rice group increased(83.24±30.15 vs.70.12±26.02 mmol·min/L, P=0.029), and the 120 min iAUC of rice in the wheat group(69.75±32.32 vs.54.87±20.43 mmol·min/L, P=0.040) increased.

Conclusion: Even to the same food, there are significant differences in the glycemic responses of people with different staple food habits, and short-term changes in the intake of staple food will lead to differences in the glycemic response.

Objective: To determine the content of vitamin K_2 in different types of fermented bean products and analyze the difference of vitamin K_(2 )content.

Methods: A total of 98 kinds of typical fermented bean products were included in Chinese traditional fermented bean products(Douchi, Sufu, soybean paste). Process, region, sales volume, raw materials and flavor were considered, and the content of vitamin K_2 in fermented bean products was determined by high performance liquid chromatography.

Results: Chinese bean fermented foods generally contained vitamin K_2, and the subtype menaquinone-7(MK-7)was the main one. The content of vitamin K_2 in Douchi was the highest(437.55 μg/100 g), the content of vitamin K_2 in Sufu and Soybean paste were lower(7.48 μg/100 g and 2.47 μg/100 g). The content of vitamin K_2 in bacterial Douchi was higher than that in Mucor type and Aspergillus oryzae type which were 403.94, 232.98 and 81.00 μg/100 g(P<0.05). Soybean type Douchi was higher than that in black bean type of Douchi which were 610.41, 178.08 μg/100 g(P<0.05), and the content of vitamin K_2 in dry Douchi was higher than the content of vitamin K_2 in water Douchi which were 1 517.45 μg/100 g, 297.58 μg/100 g(P<0.05). However, there were no significant difference in the content of vitamin K_2 in Soybean paste and Sufu in different types and regions(P > 0.05).

Conclusion: Vitamin K_2 is widely contained in Chinese fermented bean products, and its content is mainly affected by fermentation microorganisms and processing technology.

Objective: To get a better knowledge of the current situation of screen time among primary and secondary school students in all provinces of China from 2016 to 2017.

Methods: Data was from the China National Nutrition and Health Surveillance of Children and Lactating Women(2016-2017).275 monitoring points were selected from 31 provinces of China by multi-stage stratified cluster random sampling. A total of 280 primary and secondary school students from 2 primary schools, 2 junior middle schools and 1 senior high school were randomly selected from each monitoring point to complete the survey.73629 primary and secondary school students(except grade 9 and grade 12) were included in this study.

Results: From 2016 to 2017, the average daily screen time of Chinese primary and secondary school students was(1.65±1.54) hours, M(P25, P75) was 1.29(0.58, 2.21) h. In terms of provinces, the average daily electronic screen time of primary and secondary school students in Beijing, Tianjin, Jilin, Fujian, Guangdong and Hainan is more than 2 hours. In terms of rural and urban areas, the screen time of students in Beijing's rural and urban areas, Tianjin's rural areas, Hebei's urban areas, Liaoning's rural areas, Jilin's rural areas, Fujian's urban areas, Guangdong's urban areas, Guangxi's urban areas, Hainan's rural and urban areas, and Xinjiang's urban areas all exceeds 2 hours/day. Besides, screen times of rural primary and secondary school students in Beijing(Z=2.62, P<0.01), Tianjin(Z=5.94, P<0.01), Liaoning(Z=11.56, P<0.01), Jilin(Z=-7.59, P<0.01), Shanghai(Z=3.19, P<0.01), Jiangsu(Z=12.00, P<0.01), Zhejiang(Z=-4.80, P<0.01), Anhui(Z=-4.67, P<0.01), Jiangxi(Z=-3.29, P=0.01), and Sichuan(Z=-4.53, P<0.01) are longer than that of urban students.

Conclusion: There are urban-rural differences in the average daily electronic screen time and different types of electronic screen time of primary and secondary school students in China's provinces from 2016 to 2017.

Objective: To analyze the mechanism of cadmium-induced cytotoxicity in mouse testicular mesenchymal cells(TM3) with transcriptome sequencing and bioinformatics techniques.

Methods: TM3 cells were selected as the cell model and divided into control group(no cadmium treatment) and cadmium-treated group(20 μmol/L CdCl_2). After 24 hours of administration, cells were harvested to extract total RNA, and then miRNA expression profiles were obtained by sequencing program after RNA quality detection. The fold change(FC) >2, P<0.05 was used as the standard to screen for differentially expressed miRNAs. The quantitative real-time polymerase chain reaction(qRT-PCR) was used to verify the differentially expressed miRNAs. Then, their target genes were predicted by miRanda software to construct miRNA-target gene interaction network, and their target genes were enriched by gene ontology(GO) and Kyoto encyclopedia of genes and genomes(KEGG) pathway function.

Results: A total of 26 differentially expressed miRNAs were identified which may be related to cadmium-induced TM3 cytotoxicity, including 19 up-regulated and 7 down-regulated miRNAs. The result of qRT-PCR were consistent with the miRNA sequencing result. Meanwhile, bioinformatics analysis result showed that the 26 differentially expressed miRNAs predicted 657 target genes. GO enrichment was mainly classified into biological regulation, metabolic process, protein binding and catalytic activity. KEGG pathway analysis showed that target genes were significantly involved in mitogen-activated protein kinase(MAPK) and tumor necrosis factor(TNF) signal pathways closely related to inflammatory response and apoptosis.

Conclusion: Cadmium can lead to the differential expression of miRNAs in TM3 cells, and its target genes may be involved in Cd-induced TM3 cytotoxicity through signaling pathways such as MAPK and TNF.

Objective: To clarify the adverse effect of cypermethrin(CYP) on the liver and explore the underlying role of the MAPK pathway.

Methods: Twenty-four Sprague-Dawley(SD) rats were exposed to 0, 5, 10 and 20 mg/(kg·d) β-CYP by gavage for 31 days. Histomorphological and ultrastructural changes were evaluated by the hematoxylin & eosin(HE) staining and transmission electron microscope(TEM). Levels of MDA and 8-OHdG were detected by ELISA. Expressions of p-JNK and γ-H2A. X were assessed by IHC and IF respectively. RT-PCR was performed to examine mRNA levels of GPx1, GPx4, SOD1, and SOD2 in rat testes. Western blot was conducted to determine protein expressions of GPx1, SOD2, CAT, γ-H2A. X, and the MAPK pathway-associated proteins in rat testes.

Results: After β-CYP exposure, the histomorphology and ultrastructures of rat livers were abnormally altered, as evidenced by hepatic sinusoidal dilation, hepatic plate space formation, mitochondrial crest fracture, etc. Moreover, β-CYP induced mRNA levels of GPx1, GPx4, SOD1 and SOD2, as well as protein expressions of GPx1 and SOD2 in the liver. Compared to the control, GPx1 and SOD2 protein expressions were decreased by 57.9% and 50.0%(P<0.05), whereas the MDA level was increased by 56.2%(P<0.05) in the high-dose group. Additionally, the JNK/c-Jun pathway, one of MAPK pathways, in the liver was activated by β-CYP, as shown by the increase of JNK and c-Jun phosphorylation, and protein expressions of p-JNK and p-c-Jun in the high-dose group were elevated by 47.7% and 46.5%(P<0.05) in comparison to the control, but the ERK and p38 pathways were not affected after β-CYP exposure. Furthermore, β-CYP promoted 8-OHdG and γ-H2A. X expressions in the liver. Compared to the control, γ-H2A. X protein expression in the mid-and high-dose group was upregulated by 16.9% and 33.9%(P<0.05), respectively.

Conclusion: Cypermethrin had detrimental effects on the liver. CYP not only directly altered liver histomorphology and ultrastructures, but also caused oxidative stress, which activated the JNK/c-Jun pathway, finally inducing the DNA damage.

Objective: To understand the status and related factors of overweight and obesity in children and adolescents aged 6-17 in Yunnan Province.

Methods: From 2016 to 2017, 3463 children and adolescents aged 6-17 from 65 primary and secondary schools in 13 counties of Yunnan Province were selected by stratified cluster sampling method for face-to-face questionnaire survey, including 1716 boys and 1747 girls, 2098 elementary school students, 762 middle school students, 603 high school students, of which, 1368 students from urban area and 2095 students from rural area. The questionnaire included information including, weekly consumption of sugary drinks, sweets, puffed food, fruits, vegetables, breakfast, daily activities of moderate or high intensity, school sports, daily hours of playing video games and watching TV, daily sleep and outdoor activities. Height and weight were measured using standard method. SPSS20.0 was used for χ~(2 )test and multivariate Logistic regression analysis.

Results: The prevalence of overweight and obesity among children and adolescents aged 6-17 were 8.43%(292/3463) and 6.01%(208/3463) respectively. The overweight rates of male students and female students were 8.45%(145/1716) and 8.41%(147/1747) respectively, and the statistic was significant differently(χ~(2 )=0.001, P>0.05). The overweight rates of urban and rural children and adolescents were 11.99%(164/1368) and 6.11%(128/2095) respectively, and the statistic was significant differently(χ~2=37.04, P<0.01). The overweight rates of primary school, middle school and high school were 7.53%(158/2098), 9.32%(71/762) and 10.45%(63/603) respectively, and the statistic was significant differently(χ~2=6.15, P<0.05). The obesity rates of male and female students were 7.11%(122/1716) and 4.92%(86/1747) respectively, and the statistic was significant differently(χ~2=7.33, P<0.01). The obesity rates of urban and rural children and adolescents were 9.50%(130/1368) and 3.72%(78/2095) respectively, and the statistic was significant differently(χ~2=48.97, P<0.01). The obesity rates of primary school, middle school and high school were 7.67%(161/2098), 3.15%(24/762) and 3.81%(23/603), respectively, and the statistic was significant differently(χ~2=26.48, P<0.01). Multivariate Logistic regression analysis showed that cities(OR=2.025, 95%CI 1.646-2.492) and non-residential schools(OR=1.808, 95%CI 1.470-2.223) were associated with overweight and obesity in children and adolescents, both of which were statistically significant(P<0.05).

Conclusion: The prevalence of overweight and obesity among children and adolescents aged 6-17 in Yunnan Province were high. Urban, non-residential school children and adolescents are more likely to be overweight and obesity.

Objective: Using liquid chromatography-ion trap-time of flight-mass spectrometry to establish a soybean phospholipids(PL) analysis method, carry out comprehensive structural identification and quantitative analysis of soybean PL molecule species, and obtain soybean PL molecular composition and content data.

Methods: The PL profiles of 10 soybean varieties cultivated in northeast China were determined by a hydrophilic interaction liquid chromatography-ion trap-time of flight-mass spectrometry(HILIC-ESI-IT-TOF-MS) system. The hydrophilic interaction liquid chromatography realized class separation of PLs, and ion trap-time of flight-mass spectrometry realized the estimation of head group type, fatty acyl structure, and substituent position. The identified PL molecule species were quantified using accurate mass extraction and internal standard method.

Results: A total of 101 PL molecular species from 11 classes were estimated in soybean seeds, including 20 phosphatidylcholines(PC), 15 phosphatidylethanolamines(PE), 17 phosphatidylinositols(PI), 12 phosphatidylglycerols(PG), 9 phosphatidic acids(PA), 6 phosphatidylserines(PS), 5 lysophosphatidylcholines(LPC), 5 lysophosphatidylethanolamines(LPE), 6 lysophosphatidylinositols(LPI), 4 lysophosphatidylglycerols(LPG) and 2 lysophosphatidicacids(LPA). The limits of detection for the target object were ≤ 60 ng/mL and R~2 were all >0.99. The total concentration of PL ranged from 6873.1 to 12 678.6 μg/g in detected soybeans. Generally, most of the detected soybean cultivars were great resources of PL, especially SN-29, SN-61, HN-40 and DN-690. The concentrations of PC and PE in the tested soybean were higher, followed by PI, PG, PA and PS. Among the lysophospholipids, the concentration of LPC was the highest, followed by LPE, LPI, LPG and LPA.

Conclusion: The soybean PL component analysis method established based on the HILIC-IT-TOF-MS system can achieve good separation of various types of PL, and can accurately characterize the head group type, fatty acyl structure and substituent position of PL molecule species. The molecular composition and content data of soybean PL were obtained.

Objective: To understand the distribution of the content range of essential ingredients in commercial follow-up formula for older infants in China, analyze the differences between the content of essential ingredients in commercial older infant formula milk powder in China and the requirements of the new national standard(GB 10766-2021).

Methods: The label information of 478 commercial follow-up formula for older infant registered and approved from January 2017 to June 2022 were collected and entered. The distribution of essential ingredients was statistically analyzed, which was compared with the requirements of the new national food safety standard.

Results: The new national standard has 31 essential components. Compared with the old national standard(GB 10767-2010), five indicators of carbohydrate, α-linolenic acid, choline, selenium and manganese were added. The new national standard has 28 essential component requirements revised, including 13 adjusted the lower limit, 7 adjusted the upper limit, and 16 essential components added the upper limit. Among the approved 478 older infant formula milk powders, the distribution of 11 essential ingredients were all in line with the new national standard, and 14 essential ingredients were less than the lower limit of the new national standard. The essential ingredients whose minimum value was less than the lower limit of the new national standard and the proportion exceeds 50% were vitamin D, iodine and choline. with the proportions(number of cases) of 98.33%(470 cases), 74.06%(354 cases) and 72.37%(275 cases), respectively. The maximum value of essential ingredients exceeded the maximum requirements stipulated in the new national standard, and the protein in 13.18%(63 cases) of the older infant formula milk powder was higher than the maximum requirements of the new national standard.

Conclusion: The content of essential components in most commercial products in China meets the new national standard requirements. Some essential ingredients need to be adjusted.

Objective: To investigate the addition of dietary fiber in infant formula approved in recent 5 years.

Methods: A total of 1438 infant formula milk powder approved in China from January 2017 to June 2022 were collected and the addition rate, content and mixture of dietary fiber components such as galactooligosaccharide(FOS), fructooligosaccharide(GOS), polyfructose, polyglucose, raffinose and yeast β-dextran were statistically analyzed.

Results: Among the 1438 infant formulas, 84.07%(1209) were added with dietary fiber, and the addition rate increased yearly. Among them, the addition rate of GOS(79.82%) and FOS(79.74%) was the highest, and the median amount of dietary fiber components was 3.00 g/100 g. Among the products added with various dietary fiber components, there were 762 products added with GOS and FOS, The addition ratios of GOS and FOS were mainly concentrated at 1∶1.

Conclusion: The addition rate of dietary fiber in infant formula milk powder in China is constantly increasing, however there are large differences in the addition amount, dietary fiber combination and proportion of different products.

Objective: To explore the feasibility of applying graphical menu labeling.

Methods: To design a radar chart menu label. From October 2020 to April 2021, convenience sampling was adopted to recruit 1407 research subjects(986 females and 421 males) through the online platform nationwide to complete the questionnaire and simulate ordering. The survey included basic information of the research subjects, their level of nutritional knowledge, and satisfaction with the graphic menu labels. The two simulated orderings were conducted using the regular menu and the menu with graphic nutritional information, respectively. Compare the nutrition scores of the two simulated orders, the selection ratio of each dish in each major category, the energy, fat, cholesterol and sodium content, and the amount of added oil and salt of the selected dishes.

Results: Compared with using the normal menu, the nutritional score of the simulated meal ordering increased from 15.57±2.65 to 16.73±3.24(P<0.05) using a menu with graphic nutrition labels, in which people with an income of less than 4000 yuan and a graduate degree or above increased the most. The proportion of dishes with higher nutritional value has increased among pork, fish, vegetables, and soy products. The energy, fat, cholesterol, sodium content, added oil and added salt of the selected dishes are decreased from 8455(7738, 9033) kcal, 658.6(598.1, 709.3) g, 1418(1238, 1665) mg, 17 430(15 695, 19 129)mg, 455(405, 502)g, 41.5(36.5, 47.0)g to 7415(6693, 8191)kcal, 562.54(504.0, 631.2)g, 1274(1076, 1549)mg, 17 185(14 574, 19 576.8)mg, 375(334, 437) g, 38.5(32.4, 43.6) g respectively(P<0.05). The satisfaction score of the graphic nutrition label is relatively high.

Conclusion: Graphical menu labeling helps consumers to make healthier choices for catering food.