Reform of Teaching Practice of Modern Instrumental Analysis in Biotechnology Programs

Through the online and offline practical reform of the Modern Instrumental Analysis course of biotechnology majors from teaching content,teaching method,teaching demonstration to teaching effect,the traditional single offline lecture is transformed into diversified and interactive modern teaching.The practical reform enriches and optimizes the course content,perfects and improves the course assessment system,and improves the teaching quality.It achieves the student-centered and application-oriented teaching goal,and also provides reference for further cultivating high-quality applied talents.

Development Countermeasures of County-level Edible Fungi Industry in Hebei Province from the Perspective of Rural Revitalization

In recent years,the edible fungi industry in Hebei Province has developed rapidly,with gradually increased cultivation scale and production output,and has become the pillar industry of the province,playing a certain role in promoting the development of rural economy and rural revitalization.Based on the in-depth analysis of the development status,future development direction and current constraints of the edible fungi industry in each typical county of Hebei Province in recent years,the paper puts forward corresponding development countermeasures,which has certain reference value for the county-level edible fungi industry of Hebei Province to promote rural revitalization.

Dietary Enteromorpha polysaccharide-Zn supplementation regulates amino acid and fatty acid metabolism by improving the antioxidant activity in chicken

Background:Enteromorpha prolifera(E.prolifera)polysaccharide has become a promising feed additive with a variety of physiological activities,such as anti-oxidant,anti-cancer,anti-diabetic,immunomodulatory,hypolipidemic,and cation chelating ability.However,whether Enteromorpha polysaccharide-trace element complex supplementation regulates amino acid and fatty acid metabolism in chicken is largely unknown.This study was conducted to investigate the effects of E.prolifera polysaccharide(EP)-Zn supplementation on growth performance,amino acid,and fatty acid metabolism in chicken.Methods:A total of 184 one-day-old Ross-308 broiler chickens were randomly divided into two treatment groups with 8 replicates,12 chickens per replicate,and fed either the basal diet(control group)or basal diet plus E.prolifera polysaccharide-Zinc(400 mg EP-Zn/kg diet).Results:Dietary EP-Zn supplementation significantly increased(P<0.05)the body weight,average daily gain,muscle antioxidant activity,serum HDL level,and reduced serum TG and LDL concentration.In addition,dietary EPZn supplementation could modulate ileal amino acid digestibility and upregulate the mRNA expression of amino acid transporter genes in the jejunum,ileum,breast muscle,and liver tissues(P<0.05).Compared with the control group,breast meat from chickens fed EP-Zn had higher(P<0.05)Pro and Asp content,and lower(P<0.05)Val,Phe,Gly,and Cys free amino acid content.Furthermore,EP-Zn supplementation upregulated(P<0.05)the mRNA expressions of mTOR and anti-oxidant related genes,while down-regulated protein degradation related genes in the breast muscle.Breast meat from EP-Zn supplemented group had significantly lower(P<0.05)proportions ofΣn-3 PUFA,and a higher percentage ofΣn-6 PUFA and the ratio of n-6/n-3 PUFA.Besides,EP-Zn supplementation regulated lipid metabolism by inhibiting the gene expression of key enzymes involved in the fatty acid synthesis and activating genes that participated in fatty acid oxidation in the liver tissue.Conclusions:It is concluded that EP-Zn complex supplementation regulates apparent ileal amino acid digestibility,enhances amino acid metabolism,and decreases oxidative stress-associated protein breakdown,thereby improving the growth performance.Furthermore,it promotes fatty acid oxidation and restrains fat synthesis through modulating lipid metabolism-related gene expression.

Uridine dynamic administration affects the circadian variation of bile acid metabolism in high-fat-diet-fed mice

High-fat diet(HFD)is demonstrated to disturb the bile acid metabolism.The rhythm of bile acid metabolism can also be affected by uridine,whose metabolism exhibits a daily rhythm.However,the mechanism of dynamic uridine administration affecting bile acid during HFD remains unclear.In this study,C57BL/6J mice were fed HFD(the control group;CON)or HFD with oral administration of uridine in the daytime(DUR)and nighttime(NUR)to investigate the mechanism of the effect of uridine on the bile acid.This study showed that the mRNA expression of uridine transporters and circadian clock genes in the jejunum was affected by zeitgeber time(ZT)(P<0.001).Genes related to the metabolism of pyrimidines in the liver showed a high dependence on daily rhythm(P<0.01),and DUR remarkably up-regulated the expression of ribonucleotide reductase regulatory subunit M2(RRM2)(P<0.05)compared to the CON group.Importantly,the mRNA expression of bile acids nuclear receptors,bile acid synthesis,and transporters in the liver showed significantly rhythmically changed(P<0.05),and the expression of cholesterol 7-alpha-hydroxylase(CYP7A1),fibroblast growth factor receptor 4(FGFR4),Na^(+)/taurocholate co transporting polypeptide(NTCP),and bile salt export pump(BSEP)mRNAs of mice with uridine administration increased significantly(P<0.05).The mRNA expression of the transporters of cholesterol and bile acids in the ileum was also affected by ZT(P<0.01)and significantly dependent on uridine administration(P<0.05).The expression of FXR and SHP was significantly affected by ZT and uridine,respectively.In conclusion,dynamic administration of uridine could regulate the rhythm of gene expression of pyrimidine and bile acid metabolism in the liver and ileum of HFD-fed mice,which contributed to the further study of circadian rhythmic physiological and pathological changes of bile acids.

快速稳定性分析仪评价乳液中乳粒的稳定性

本研究对乳液中乳粒在贮存过程中的稳定性进行了评价,并区分了不同处方的乳粒稳定性。采用快速稳定性分析仪-LUMisizer,评估冻融循环对乳粒的影响,结合粒径参数、zeta电位和冷冻透射电镜观察。经过冻融循环后,乳粒的性状、粒径参数和透光率发生显著变化。乳粒在冻融循环后破乳(可见浮油和乳化层)。不同丙泊酚含量(10:1和20:1,m/v)的处方,乳粒的稳定性有显著差异。快速稳定性分析仪可以区分加速破坏的乳粒从而评价其稳定性,有效补充传统方法的不足,可对脂肪乳中的乳粒进行更好的质量控制。

低轴压比聚乙烯醇纤维增强水泥基复合材料中长柱抗震性能试验

已有对聚乙烯醇纤维增强水泥基复合材料(PVA/C)柱抗震性能的研究大多针对短柱,且PVA/C一般只在节点及其邻近部位局部设置。基于此,本文对低轴压比且沿柱全高设置的PVA/C中长柱进行低周反复荷载试验,变化参数为纤维体积分数ρf和体积配箍率ρv。通过试验,得出以下结论:所有试件均发生弯曲破坏;当ρf和ρv分别在试验设计范围内增大时,试件的裂缝控制能力、延性、截面转动能力及耗能能力均提高,刚度退化及承载力衰减速度减小;ρf的增大可较大程度提高试件开裂荷载,而对峰值荷载影响较小;ρf由0 vol%提高到2 vol%,位移延性系数、耗能比及开裂荷载分别提高52.9%、112.3%和51.1%;掺加适量纤维后,即使降低配箍率,试件也可保持良好的抗震性能和裂缝形态。根据本文试验数据并收集其他相关文献试验数据,拟合得出位移延性系数与ρf和ρv之间的关系式。最后总结了各类PVA/C柱抗震性能差异。

Enteromorpha polysaccharide-zinc replacing prophylactic antibiotics contributes to improving gut health of weaned piglets

This research aimed to study whether Enteromorpha polysaccharide-zinc(EP-Zn)can act as an alternative to antibiotics in weaned piglet feeds.Two hundred and twenty-four weaned piglets from 14 pens were randomly assigned into 1 of 2 groups according to their body weight and litter size(7 pens/group).The piglets in the antibiotics group were fed with olaquindox at 400 mg/kg and enduracidin at 800 mg/kg basal diet,and piglets in the EP-Zn group were fed with EP-Zn at 800 mg/kg basal diet.One piglet per pen was selected to collect samples after 14 d of feeding.Results showed that EP-Zn supplementation significantly increased the plasma anti-oxidants level compared with the antibiotics group.However,a nonsignificant difference was observed in growth performance between treatment groups.Additionally,the intestinal tight junction(TJ)protein expression and the histopathologic evaluation data showed that EP-Zn contributed to improving intestinal development.Further,piglets in the EP-Zn group had a lower level of intestinal inflammation-related cytokines including IL-6(P<0.001),IL-8(P<0.05),IL-12(P<0.05)and tumor necrosis factor-α(TNF-α)(P<0.001),and showed an inhibition of the phosphor-ylation nuclear transcription factor-kappa B(p-NF-kB)(P<0.05)and total NF-kB(P<0.001)level in the jejunal mucosa.Taken together,it is supposed that EP-Zn,to some extent,would be a potent alternative to prophylactic antibiotics in improving the health status of weaned piglets.

Dietary supplementation of Lonicera macranthoides leaf powder improves amino acid profiles in serum and longissimus thoracis muscle of growing-finishing pigs

A 60-days feeding trial was conducted to determine the effect of dietary supplementation of Lonicera macranthoides leaf(LML) on growth performance, meat quality, and free amino acid profiles in growingfinishing pigs. L. macranthoides leaves were harvested, air-dried and milled to powder. A total of 288 crossbred barrows(Large White x Landrace) with an average initial BW of 54.0 ± 3.4 kg were randomly allocated to 3 treatment groups and fed either a basal diet or a diet supplemented with 0.5% or 1.0% LML powder. Results showed that diet supplemented with LML powder did not affect average daily feed intake(ADFI) and feed: gain ratio(P> 0.05) in growing-finishing pigs. Moreover, diet supplemented with LML powder showed no significant effects on carcass traits(P > 0.05) including dressing percentage,backfat thickness and loin muscle area, and meat quality traits(P > 0.05) including meat color, intramuscular fat and cooking loss. However, diet supplemented with LML powder significantly improved free amino acid profiles in serum and longissimus thoracis muscle in growing-finishing pigs. Most importantly, dietary LML powder increased total free amino acids content(P < 0.001) and essential free amino acid content(P < 0.001) in longissimus thoracis muscle. These results indicate that LML has the potential to improve the nutritional value of meat through improving free amino acid profiles.

Manganese methionine hydroxy analog chelated affects growth performance,trace element deposition and expression of related transporters of broilers

The present study aimed to evaluate the effects of manganese methionine hydroxyl analog chelated(Mn-MHAC)as a manganese(Mn)source on growth performance and trace element deposition in broilers.A total of 432 Arbor Acres commercial female broilers were fed a basal corn-soybean diet containing Mn at 25.64 mg/kg diet for 10 d.They were then randomly assigned to 6 groups,including a control group(the basal diet),a Mn sulfate group(the basal diet supplemented with Mn at 100 mg/kg diet),and 4 Mn-MHAC groups(the basal diet supplemented with Mn-MHAC at 25,50,75 and 100 mg Mn/kg diet,respectively).The results showed that compared with the control group,groups supplemented with Mn-MHAC had a positive effect on BW(quadratic,P=0.017)and ADG(quadratic,P=0.017).Moreover,the Mn-MHAC(50 mg Mn/kg diet)group had significantly greater BW and ADG(P<0.05)compared with the other Mn-MHAC groups.Trace element deposition results also showed that tibial Mn increased(linear or quadratic,P-0.002 and 0.009,respectively)in groups fed diets with increased levels of Mn-MHAC.In contrast,Fe deposition decreased both in the heart(linear,P-0.020)and tibia(P<0.05).In addition,the Mn-MHAC supplement noticeably lowered serum Mn-SOD activity(linear or quadratic,P-0.048 and 0.019,respectively).The relative mRNA levels of divalent metal transporter 1(DMT1)(P=0.024),ferro-portin 1(FPN1)(P=0.049),and Cu transporter-1(CTR1)(P<0.001)in the duodenum,as well as CTR1 in the jejunum and ileum(P=0.040 and 0.011,respectively)were higher in the Mn-supplemented group than in the control group.Furthermore,the relative mRNA level of DMT1 in the jejunum and ileum of broilers in the Mn-MHAC group(50 mg Mn/kg diet)did not differ from those in the control group,but was lower than those in the Mn sulfate group(P<0.05).In conclusion,Mn-MHAC dietary supplementation improved the growth performance and trace element deposition in broilers.From this study,we recommend the opti-mum Mn-MHAC level to meet the Mn requirement of broilers is 50 to 75 mg Mn/kg diet.

Effects of a two-meal daily feeding pattern with varied crude protein levels on growth performance and antioxidant indexes in pigs

The present study aimed to evaluate the effects of daily feeding pattern on growth performance, blood biochemistry, and antioxidant indexes in pigs. One hundred and eighty female Duroc x Landrace x Yorkshire(DLY) pigs with similar body weight(11.00 ± 0.12 kg) were randomly assigned to 3 groups: the control group(fed 17.01% CP diet, twice daily); high-low group(H-L group, fed18.33% CP diet in the morning, followed by 15.70% CP diet in the afternoon); and low-high group(L-H group, fed 15.70% CP diet in the morning, followed by 18.33% CP diet in the afternoon)(n = 6). Comparable amounts of their respective diets were given at 05:30 and 15:00 throughout the experimental periods to make all the treatments consumed the same type of food and the same amount of calories on a daily basis. On day 30, one pig was randomly selected per litter for blood samples. Compared with the control group, ADG in the H-L and L-H groups increased by 8.11% and 16.23%, but not significant(P > 0.05); and blood urea nitrogen(BUN) in the H-L and L-H groups decreased by 26.76% and 41.04%(P < 0.05), respectively. The H-L group feeding pattern could significantly improve levels of serum superoxide dismutase(SOD), when compared with the control group. These findings suggest that the twomeal daily feeding pattern with varied levels of CP affects serum levels of BUN and SOD. These changes could effectively silightly improve growth performance and antioxidant capacity in pigs without incurring increased feeding costs.

Effects of catechins on litter size,reproductive performance and antioxidative status in gestating sows

This study was conducted to investigate the effects of catechins on reproductive performance, antioxidative capacity and immune function of gestating sows. A total of 60 cross-bred（Landrace × Large White） multiparious sows were blocked by body weight, parity and backfact and randomly allocated to 1 of 5 treatments: 0.100,200,300, or 400 mg/kg catechins. Dietary treatments were imposed from mating to d 40 of gestation of sows. At farrowing, litter total born, born alive, dead, and normal-（healthy piglets,>0.85 kg） and low-birth weight piglets（<0.85 kg） were recorded. Within 3.00 ± 0.50 days after farrowing litter size was standardized to 8,00 ± 1.50 piglets within treatment. The piglets were weighed at birth（d 1） and weaning（d 28）. Sows serum samples were obtained from blood samples collected on d 40 of gestation for analyses of glutathione peroxidase（GSH-Px）, superoxide dismutase（SOD）, catalase（CAT）,malondialdehyde（MDA）, hydrogen peroxide（H2 O2）, nitric oxide synthetase（NOS） and nitrogen monoxide（NO）. Our results showed that supplementation of catechins at levels of 200 or 300 mg/kg led to improvements in litter born alive（P < 0.01） and piglet born healthy（P < 0.01） and a decrease in stillborn（P < 0.05） at farrowing when compared with the control. In comparison with the control, catechins at any supplemental levels all enhanced the serum SOD（P < 0.05） and CAT（P < 0.01） activities of sows at farrowing but no obvious differences in the serum GSH-Px and NOS activities were observed in this trial（P > 0.05）. Sows received 200 mg catechin per kg diets showed a reduction（P < 0.05） of the serum MDA level at farrowing compared with all other treatments. Sows received all the levels of catechin showed a reduction（P < 0.05） of serum H2 O2 level compared with sows received the control diet on both d 40 of gestation and farrowing. Our results demonstrated that the catechins may be a potential antioxidant to increase the reproductive performance and antioxidative capacity of sows when it was added into diets during the early gestation.

Yeast-based nucleotide supplementation in mother sows modifies the intestinal barrier function and immune response of neonatal pigs

In the present study,we aimed to evaluate the effects of maternal yeast-based nucleotide(YN)sup-plementation on the intestinal immune response and barrier function in neonatal pigs,as well as the diarrhoea rate and growth performance in suckling piglets.Sixty-four late-gestation sows were assigned to the following groups:the CON(fed a basal diet)and YN groups(fed a basal diet with 4 g YN/kg diet).The experiment started on d 85 of gestation and ended on d 20 of lactation.Diarrhoea rate and average daily gain of the piglets were recorded,and samples of blood and intestines from neonatal piglets were collected before they consumed colostrum during farrowing.Compared with the CON group,maternal YN supplementation increased the weaning weight of litter and decreased the diarrhoea rate(P<0.01).In addition,maternal YN supplementation promoted the ileal villus development in the neonates compared with that in the CON group(P<0.01).Maternal YN supplementation also increased the ileal secretory immunoglobulin A(sIgA)level compared with that in the CON group(P<0.05).The real-time PCR results showed that maternal dietary YN supplementation increased the jejunal and ileal expression of interleukin(IL)-17,IL-8,IL-1β,IL-10 and tumor necrosis factor(TNF)-αin the neonates compared with that in the CON group(P<0.05).Overall,maternal nucleotide supplementation improved the villus development and innate immunity of neonatal piglets during late pregnancy.This may be associated with the decrease in diarrhoea and the increase in weaning weight of the litter of suckling piglets.

Oral administration of dibutyryl adenosine cyclophosphate improved growth performance in weaning piglets by enhancing lipid fatty acids metabolism

Dibutyryl adenosine cyclophosphate(dbc AMP-Ca), an analog of cyclic adenosine monophosphate(c AMP), plays greater roles in regulating physiological activities and energy metabolism than c AMP. The aim of this study was to investigate the effect of oral administration of dbc AMP-Ca on growth performance and fatty acids metabolism in weaning piglets. A total of 14 early weaning piglets(7 ± 1 d of age,3.31 ± 0.09 kg, Landrace ? Large White ? Duroc) were randomly divided into 2 groups: control group and dbc AMP-Ca group, and the piglets received 7 m L of 0.9% Na Cl or 1.5 mg dbc AMP-Ca dissolved in 7 m L of 0.9% Na Cl per day for 10 d, respectively. The results showed that the average daily gain(ADG)increased by 109.17%(P < 0.05) in the dbc AMP-Ca group compared with the control group. Besides,dbc AMP-Ca significantly decreased blood high density lipoprotein cholesterol(HDLC) concentration(P < 0.05) and significantly increased blood low density lipoprotein cholesterol(LDLC) concentration(P < 0.05) compared with the control group. Further, liver C18:2 n6 t content significantly increased in dbc AMP-Ca group(P < 0.05) compared with the control group. With the increase of C18:2 n6 t content,the m RNA expression levels of peroxisome proliferator-activated receptor a(PPARa) and hormone sensitive glycerol three lipase(HSL), of which genes are related to lipid metabolism, were also significantly increased(P < 0.05 or P < 0.01). All of the results indicated that dbc AMP-Ca improved the ADG, which was probably done by regulating fatty acids metabolism in the liver of weaning piglets.

Prevalence of Metabolic Syndrome and Risk Factors Among Chinese Adults:Results from a Population-Based Study—Beijing,China,2017–2018

Summary What is already known about this topic?Metabolic syndrome(MetS)is one of the most easily available health indicative markers for cardiovascular diseases,and it has become a major public health problem worldwide due to increasing urbanization and aging populations.The prevalence of MetS increased dramatically in China,however,there are no records of MetS defined by the 2017 Chinese Diabetes Society for Beijing by far.What is added by this report?In this study,the data of 24,412 participants aged 18–74 years from a large population-based study in Beijing was collected.The overall prevalence of MetS among Beijing residents was 24.5%.The prevalence was 35.2%in males and 15.4%in females.What are the implications for public health practice?Effective public health strategies should target males,people with older age,lower education,higher body mass index,smokers,those who drink alcohol,those who are unemployed or retired,and those who live in rural areas on MetS prevention and control.

Hepatic lipid metabolism is affected by a daily 3-meal pattern with varying dietary crude protein with a pig model

The present study was conducted to evaluate the effects of 3 meals administered daily with varying dietary crude protein(CP)contents on hepatic lipid metabolism with a pig model.Pigs were divided into3 groups according to the following feeding patterns:feeding a basal CP diet 3 times daily(3 C);feeding a high CP diet for breakfast,the basal CP diet for lunch,and a low CP diet for dinner(HCL);and feeding the low CP diet for breakfast,the basal CP diet for lunch,and the high protein diet for dinner(LCH).Three groups took equivalent diet per meal ensuring that every pig was fed with similar dietary formulae daily.Results showed that HCL feeding pattern reduced the relative kidney weight(P<0.05),and LCH feeding pattern increased the relative liver weight of pigs(P<0.05)when compared with those in the 3 C group.Plasma urea nitrogen(P<0.01)and lipase(P<0.05)decreased in the HCL group but increased in the LCH group.Both HCL and LCH feeding patterns reduced plasma triglycerides(P<0.01),non-esterified fatty acids(NEFA)(P<0.01),and hepatic crude fat(0.05<P<0.10)of pigs.Real-time quantitative PCR(RTqPCR)results showed that dynamic feeding patterns down-regulated(P<0.05)the mRNA level of lipid metabolism related genes,including adipose triglyceride lipase(ATGL),acetyl-CoA carboxylase(ACCa),liver X receptor(LXRα)in the liver,and negatively regulate elements of circadian clock,including period 1(Perl),period 2(Per2),cryptochrome(Cry2),which in turn,upregulated(P<0.05)the protein expression of positive regulate element brain and muscle Arnt-like 1(BMAL1)when compared with 3 C group.Overall,our findings suggested that dynamic feeding patterns may affect hepatic lipid metabolism via regulation of the circadian clock.