内蒙古自治区生禽畜肉沙门氏菌、单核细胞增生李斯特菌和弯曲菌的污染监测分析

目的:了解内蒙古自治区生禽畜肉中沙门氏菌、单核细胞增生李斯特菌和弯曲菌污染状况,为防治食源性疾病提供基础资料,为相关监督部门提供指导意见。方法:2016~2020年,从内蒙古自治区12个盟市采集生禽肉和牲畜肉共3171份样品。依据《食品安全国家标准》(GB 4789-2016、GB 4789-2014)和食源性疾病监测工作手册要求进行致病菌的监测。结果:2016~2020年,在3171份样品中共检出阳性致病菌346株,总检出率为10.91%(346/3171),其中沙门氏菌、单核细胞增生李斯特菌和弯曲菌的总检出率依次为8.56%(85/993)、5.62%(50/889)和16.37%(211/1289);散装样品致病菌污染率高于预包装;冷冻肉中单核细胞增生李斯特菌的检出率最高,为17.53%(27/154);沙门氏菌在网店和便利店/零售店的检出率较高,分别为22.22%(4/18)和14.57%(22/151);弯曲菌在养殖环节的检出率最高,为40.55%(103/254),屠宰环节中样品均未检出。结论:2016~2020年内蒙古自治区生禽畜肉中弯曲菌污染最高,单核细胞增生李斯特氏菌污染率较低。为减少食源性疾病的发生率,应加强我区生禽畜肉在不同环节的监督管理,保障国民的食品安全与健康。

即食生椒牦牛肉加工工艺研究

文章对生椒牦牛肉加工过程中的常压状态下的加热时间与高压状态下的加热时间、调味配方以及成品杀菌进行研究。通过实验及相关数据分析,优化了即食生椒牦牛肉生产工艺,最终确定了最佳常压加热时间50min,高压加热时间为30min,最佳加热方式为常压加热时间50min。确定了即食生椒牦牛肉调味最佳配方:鲜青花椒110g、青小米椒100g、盐80g、八角30g、老抽50g、料酒50g、水1000g。同时,分析了不同杀菌时间对成品品质及理化指标的影响,最终确定了在121℃条件下,杀菌时间为8min。研究为牦牛肉即食产品开发以及传统烹饪工业化生产提供参考依据。

生啫叮叮肉

生啫叮叮肉，这是成都温江区瑞香金阁老板李辉自创的一道菜。成菜上桌时，香气四溢，滚烫鲜嫩（该店的更多特色菜，读者朋友可请参见3月份的《四川烹饪》下半也刊）。这道菜还适合堂烹，可以让食客在香气氤氲中期待它上桌，这多少也能增加一点悬念。

噬菌体对鸡肉表面耐药沙门氏菌的抑制作用

目的探究裂解性噬菌体对鸡肉表面耐药沙门氏菌的抑制效果。方法以实验室前期筛选得到的沙门氏菌噬菌体D1-2和Pu20为研究材料,采用单独使用和1:1混合的方式对生鸡胸肉表面多重耐药沙门氏菌的抑制效果进行研究。结果与单一噬菌体相比,噬菌体混合制剂对生鸡胸肉表面多重耐药沙门氏菌抑菌效果更显著。在4℃时,采用感染复数(multiplicity of infection MOI)值为10000的噬菌体混合制剂,其对肠炎沙门氏菌11561的抑菌效率达到98%,且可以完全抑制鼠伤寒沙门氏菌SJTUF13277。结论该方法对鸡肉表面沙门氏菌的抑制作用显著,可为噬菌体控制耐药沙门氏菌提供实验数据与理论基础。

虫生真菌非核糖体多肽活性产物生物合成潜力预测

肉座菌目虫生真菌合成的非核糖体多肽类天然产物具有抗菌、杀虫、抗癌、调节免疫等生物活性,在临床和农业等领域有重要应用价值。近年来,随着真菌基因组测序数量的迅速增加、注释和分析工具的不断进步,人们发现真菌基因组中存在大量产物未知的天然产物合成基因。准确有效地预测这些基因的功能,筛选最有潜力合成新颖天然产物的基因簇,可以提高天然产物挖掘的效率。本研究选取40株肉座菌目虫生真菌基因组,系统分析了编码非核糖体多肽合成酶的基因及基因簇。基于隐马尔可夫模型,预测了445个模块型非核糖体多肽合成酶和1243个类非核糖体多肽合成酶;通过提取腺苷酰化结构域,构建序列相似性网络,以已知功能的非核糖体多肽合成酶作为标签,利用马尔可夫聚类算法,分析了非核糖体多肽产物的主要类别,发现了可能合成线性多肽、环缩肽、脂多肽、生物碱等新型结构化合物的基因簇。研究结果不仅揭示了肉座菌目虫生真菌合成非核糖体多肽活性产物的巨大潜力,而且为通过激活沉默基因簇挖掘新产物、利用合成生物学手段改造合成途径提供参考。

Prognositic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma

Objective:Osteosarcoma is a highly aggressive primary malignant bone tumor commonly seen in children and adolescents,with a poor prognosis.Anchorage-dependent cell death(anoikis)has been proven to be indispensable in tumor metastasis,regulating the migration and adhesion of tumor cells at the primary site.However,as a type of programmed cell death,anoikis is rarely studied in osteosarcoma,especially in the tumor immune microenvironment.This study aims to clarify prognostic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma.Methods:Anoikis-related genes(ANRGs)were obtained from GeneCards.Clinical information and ANRGs expression profiles of osteosarcoma patients were sourced from the therapeutically applicable research to generate effective therapies and Gene Expression Omnibus(GEO)databases.ANRGs highly associated with tumor immune microenvironment were identified by the estimate package and the weighted gene coexpression network analysis(WGCNA)algorithm.Machine learning algorithms were performed to construct long-term survival predictive strategy,each sample was divided into high-risk and low-risk subgroups,which was further verified in the GEO cohort.Finally,based on single-cell RNA-seq from the GEO database,analysis was done on the function of signature genes in the osteosarcoma tumor microenvironment.Results:A total of 51 hub ANRGs closely associated with the tumor microenvironment were identified,from which 3 genes(MERTK,BNIP3,S100A8)were selected to construct the prognostic model.Significant differences in immune cell activation and immune-related signaling pathways were observed between the high-risk and low-risk groups based on tumor microenvironment analysis(all P<0.05).Additionally,characteristic genes within the osteosarcoma microenvironment were identified in regulation of intercellular crosstalk through the GAS6-MERTK signaling pathway.Conclusion:The prognostic model based on ANRGs and tumor microenvironment demonstrate good predictive power and provide more personalized treatment options for patients with osteosarcoma.

Phenylethanoid Glycosides from Cultivated Cistanche salsa

Introduction The plants of genus Cistanche G. Beck, which belong to Orobanchaceae family, include about twenty species, and there are four species and one variety are distributed in the northwest part of China. The dried fleshy stem of Cistanche genus plant known as ＇Roucongrong＇ in Chinese traditional medicine, has long been used for kidney deficiency, female infertility, morbid leucorrhea, and neurasthenia. Studies on active components and pharmacological activities show that it possesses significant activities in enhancing potency, anti-fatigue, immuno-modulability, etc, and phenylethanoid glycosides are the major active components. Due to excessive exploitation, its natural resources are facing with exhaustion. In order to improve this situation, the plant has been cultivated on a large scale in the northwest part of China. Up to now, the chemical investigations of the cultivated Cistartcbe salsa have not been undertaken. In this paper we report seven phenylethanoid glycosides from the cultivated Cistanche salsa： echinacoside （1）, cistanoside A （2）, acteoside （3）, isoacteoside （4）, 2＇-acetylacteoside （5）, tubuloside B （6）, and eutigoside A （7）. Among them, compound 7 isolated fronl family Orobanchaceae was reported previously, and compounds 1, 2, 3, 4, 5 and 6 from the cultivated Cistanche salsa are reported for the first time.

Quantitative Study on Expression of MSTN Gene in Different Tissues of Tibetan Sheep at Different Ages

[Objective] The aim was to investigate the difference in MSTN gene expression in different tissues of Tibetan sheep at different ages.[Method] According to the sequence（NM_001009428.1）published in GenBank,a pair of specific primers was designed to amplify part of cDNA sequence of MSTN by using QRT-PCR technique.The relative expression level of MSTN gene in rennet stomach,rumen,leg muscle and cardiac muscle of Tibetan sheep at different ages were analyzed.[Result] After normalization with β-actin gene,the relative expression level of MSTN gene in the 6-month-old Tibetan sheep was the highest and it was 2.52 times than that in 12-month-old Tibetan sheep（P0.05）,the relative expression level of MSTN gene in leg muscle was the highest among all tissues and it was 3 984.78 times than that in rumen（P0.01）.[Conclusion] The results established theoretical foundation for the correct use of MSTN antibody.

The Ratio of Flesh to Body and Analysis on Biochemical Composition of Muscle in Pachyhynobius Shangchengensis

[Objective] The ratio of flesh content and biochemical compositions in muscles of Pachyhynobius shangchengensis were researched in this experiment to provide basic referrences for studying nutritive physiological ecology of Pachyhynobius shangchengensis. [Method] The biochemical analytic method was used to detect the ratio of flesh content and biochemical compositions in muscle of Pachyhynobius shangchengensis. [Result] The ratio of flesh contents of female and male Pachyhynobius shangchengensis were 54.93% and 55.84% respectively. The contents of protein, total saccharides and fatty acid of female Pachyhynobius shangchengensis were 15.44% ,1.70% and 0.68% respectively,while the same contents of male Pachyhynobius shangchengensis were 15.67%, 1.89% and 0.53% respectively. The total content of 18 kinds of amino acids was 12.72% （the proportion in fresh weight）, among which the content of 8 kinds of essential amino acids was 4.68%. The essential amino acids index（EAAI） was 72.68 and limiting amino acids was valine. There were 11 kinds of fatty acids in muscles of Pachyhynobius shangchengensis, among which the content of unsaturated fatty acids （80.02%） was higher than that of saturated fatty acids（ 19.98% ）. [ Conclusion] Pachyhynobius shangchengensis was a kind of valuable natural resource belonging to the nutritious type of low fat content and high protein content.

Effects of Probiotics on Growth Performance and Blood Biochemical Indexes of Cherry Valley Ducks

In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. Total 240 1-d-old Cherry Valley ducks were selected, and they were randomly divided into 4 groups, including 1 control group and 3 treatment groups. There were 3 replicates for each group and there were 20 ducks for each replicate. The ducks in the control group were fed the basal diet, and the ducks in the 3 treatment groups were fed the basal diet added with Lactobacillus, Bacillus natto and florfenicol, respectively. The test lasted for 42 d. The results showed that the addition of Lactobacillus and Bacillus natto could improve the average daily weight gain and final average weight （P〈0.05） of Cherry Valley ducks, and reduce the glutamic-pyruvic transaminase ac- tivity, alkaline phosphatase activity and serum urinary nitrogen content in duck blood （P〈0.05） and reduce the creatinine content and total cholesterol content in Cherry Valley ducks （P〉0.05）; at the same time, adding probiotics to feed could also in- crease the grass economic benefits of Cherry Valley ducks. In overall, the effects of adding probiotics were better than those of adding antibiotic.

Effects of Different Concentrations of Homologous Probiotics on Small Intestinal Mucosa Structure of 42-day-old Broilers

In the study, the methods of applied histology and histochemistry were used to determine intestinal villus length, crypt depth, the ratio of intestinal villus length to crypt depth, mucous membrane thickness and intestinal wall thickness of duodenum, jejunum and ileum of 42-day-old broilers, so as to study the effects of different conncentrations of homologous probiottcs on small intestinal mucosa struc- ture of the broilers. The results showed that the effect of 0.3% probiotics on small intestine mucosal structures was the best, such as the length of intestinal villus was the longest, the ratio of villus length to crypt depth was the largest, the thins of mucous membrane and intestinal wall was the thickest. These showed that 0,3% probiotics had best effect on improving and enhancing the digestion-absorption func- tion of the small intestine of the broilers.

Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi Seeds under Different Temperatures

[Objective] To study the germination characteristics and secondary metabolism of Scutellaria baicalensis Georgi seeds under different temperatures.[Method]The activities of superoxide dismutase（SOD）and peroxidase（POD）were determined with lactoflavine-NBT method and guaiacol-colorimetry assay,respectively.The catalase（CAT）,ascorbate peroxidase（APX）,phenylalanine ammonia-lyase（PAL）and cinnamic acid 4-Hydroxylase（C4H）were determined with ultraviolet spectrophotometry.The secondary metabolites were detected by High Performance Liquid Chromatography（HPLC）.[Result]The germination percentage,germination potentiality and germination index were seriously affected by low or high temperature.The proper germination temperature was 20-25 ℃.The activities of SOD,POD and CAT were significantly decreased as comparison to suitable temperature.The activities of PAL and C4H were also significantly decreased as comparision to suitable temperature which was accordance to the secondary metabolites.There was a positive correlation between the flavonoids content and the PAL and C4H activity（r=0.956,r=0.951,P0.05）.[Conclusion]The quality of the skullcaps could be improved by improving the activity of PAL and C4H.The proper temperature for the seed germination and the formation of secondary metabolites was 20 ℃.

Developmental Changes of IGF-Ⅰ mRNA Expression Level in Sheep Muscle

[ Objective] To detect the mRNA of muscle insulin-like growth factorl （IGF-I） in the early development of Kazak sheep and Xinjiang fine-wool sheep, so as to provide information for the research about the early growth and development of sheep. [ Method] With real-time quan- titative PCR, the muscle IGF-I mRNA level was separately detected in two varieties of sheep at 2, 30, 60, 90 and 120 days old. Then the data was analyzed with SPSS software. [ Result] The IGF-I mRNA in sheep muscle first increased and then decreased with ages, peaking at 30 days old in Kazak sheep and at 60 days old in Xinjiang fine-wool sheep. The IGF-I expression level of Kazak sheep had no significant difference with Xinjiang fine-wool sheep at 2 or 90 days old （ P 〉0.05）, but was lower than that of the latter with extremely significant difference （ P 〈0.01 ） from 30 to 60 days old. [ Conclusion] The male Kazak sheep and Xinjiang fine-wool sheep have similar model of developmental changes of muscular IGF-I mRNA, but the expression level is different between these two species.

Comparison of Soleus Muscle Fibers in Rats and Rabbits at Different Stages of Postnatal Development

In the present study,the effects of postnatal development on the number and distribution of skeletal muscle fibers of different types in hind leg of rat and rabbit were studied.The soleus muscles of rats aged 2 days,2,4,6,8,and 10 weeks (body weight 10,32,95,190,280,and 320 g),and rabbits aged 2 days,2,4,8,12,16,20,and 24 weeks (body weight 100,220,400,750,1 200,1 600,2 100,and 2 500 g) were stained with succinic dehydrogenase.With an image analysis system,the X-Y coordinates of fibers were used to analyze the growth-related changes.The results of present study showed that three types of fibers were found in the soleus muscles of rat and rabbit,i.e.,type Ⅰ (slow oxidative),ⅡX (fast oxidative),and ⅡA (fast oxidative glycolytic).The type Ⅰ fibers were present throughout the muscle that had a uniform distribution and tended to increase in number with aging.Type ⅡX fibers were scattered throughout the muscle and decreased markedly in number with aging.Type ⅡA fibers were located at the central and deep regions,and showed a little or no change in number and distribution with aging.While be of age,type ⅡA and ⅡX fibers became restricted to the superficial region.No type ⅡB fibers were detected.Type ⅡA fibers had the largest diameter,type Ⅰ intermediate and type ⅡX the smallest.Mean cross-sectional area of each type fibers of rabbits was larger than that of rats.The present results indicate that the number and distribution of muscle fibers of different types in hind limb of rat and rabbit change with the process of postnatal growth.

Changes of Primary and Secondary Metabolism during the Seed Germination of Scutellaria baicalensis Georgi

[Objective] To investigate the primary and secondary metabolism during the seed germination of Scutellaria baicalensis Georgi. [Method] The activities of SOD and POD were determined with lactoflavine-NBT method and guaiacol-colorimetry as- say, respectively. The activities of CAT, APX,PAL and C4H were determined with ultraviolet spectrophotometry. The contents of secondary metabolites were detected by High-performance Liquid Chromatography （HPLC）. [Result] The results indicate that the soluble sugar content decreased during the first 5 days and then increased when the cotyledons formed. The contents of PAL, C4H and CHS continuously in- creased at different stages during the seed germination process. The secondary metabolites also showed the consistent variation trend. In addition, the contents of secondary metabolites had significant positive correlation with the key enzyme activi- ty. [Conclusion] The formation of secondary metabolites is significantly positively cor- related with the key enzyme during the seed germination process. Therefore, the key enzyme activity can be enhanced by adopting appropriate measures to improve the secondary metabolites, thereby obtaining high-quality medicinal materials.

徐州市市售生肉中3种食源性致病菌污染及药敏情况分析

目的了解徐州市市售生禽畜肉中3种常见食源性致病菌污染及药敏情况,为3种致病菌防治工作提供依据。方法随机采集2018年、2020年及2021年市售生禽畜肉,进行沙门菌、弯曲菌及单核细胞增生李斯特菌的鉴定,对分离出的菌株进行药敏试验。结果192份样品中沙门菌的检出率为32.29%(62/192),弯曲菌的检出率为31.77%(61/192),单核细胞增生李斯特菌检出率为28.17%(40/142)。62株沙门菌耐药较严重的前3种抗生素为有氨苄西林(67.74%)、氨苄西林-舒巴坦(59.68%)、四环素(56.45%);34株结肠弯曲菌耐药较严重的前3种抗生素为萘啶酸(100.00%)、环丙沙(100.00%)、四环素(100.00%);27株空肠弯曲菌耐药较严重的前3种抗生素为萘啶酸(96.30%)、环丙沙星(96.30%)、四环素(88.89%);40株单核细胞增生李斯特菌对氨苄西林耐药率最高,为10.00%,其次是青霉素(5.00%),对其余抗生素均敏感。结论徐州市生肉中3种致病菌污染较严重,沙门菌和弯曲菌耐药严重,应当引起相关部门的高度重视。

Vascular Channel Formation by Osteosarcoma Cells in Vitro: Vasculogenic Mimicry

Objective: To observe whether there is evidence for vascular channel formation by osteosarcoma cellsin vitro and to illustrate mechanism of vasculogenic mimicry in osteosarcoma.Methods: Osteosarcoma cell lines (U-2OS) were tested for their ability to form tubular networks in three-dimensional culture containing type I collagen. The structures of the tubular networks were observed under a phase contrast microscope and an electron microscope.Results: Observation under light microscopy and electron microscopy showed that high aggressive osteosarcoma cells line (U-2OS) formed networks containing channels when grown in three-dimensional culture containing type I collagen in the absence of endothelial cells or fibroblasts.Conclusion: These observations strongly suggest that aggressive osteosarcoma cells may generate vascular channels that facilitate tumor perfusion independent of tumor angiogenesis and have the ability of vasculogenic mimicry. Key words osteosarcoma cells line - vasculogenesis mimicry - angiogenesis - 3-dimensional cultures This study was supported in part by the National Natural Sciences Foundation of China (No. 30271314).

Association of myostatin Variants with Growth Traits of Zhikong Scallop(Chlamys farreri)

Scallop is a popular sea food and an important aquaculture shellfish.Identification of genes and genetic variants relating to scallop growth could benefit high-yielding scallop breeding.Myostatin(MSTN) is a conservative regulator of muscle growth,and has become one of the most important target genes for genetic improvement of the production of farmed animals.In this study,four single nucleotide polymorphisms(SNPs) were identified in the 5' flanking region of MSTN gene(Cf MSTN) in Zhikong scallop(Chlamys farreri).The association of these SNPs with scallop growth traits,including shell length,shell height,body weight and striated muscle weight was analyzed.The SNP g-1162G>T was found to associate with shell length,shell height,and striated muscle weight.The TT type scallops showed significantly higher trait values than those of GT type,and the GG type individuals exhibited median values.On the contrary,significantly more Cf MSTN transcripts were detected in the striated muscle of GT type scallops than in those of TT and GG type ones.Our results suggested that Cf MSTN might regulate the scallop muscle growth negatively,and SNP g-1162G>T can be used as a candidate marker for the selective breeding of high-yielding scallop.

Plants regenerated from mesophyll protoplasts of white mulberry

Morus alba(white mulberry) mesophyll protoplasts were isolated from leaves of 30-45 day old sterile shoots,with protoplast yields of 2.5 x 107 g-1/F.W. after purification. The protoplasts were cultured in a modified K8P liquid medium containing 0.2 mg/L 2,4-D(2,4- Dichlorophe-noxy acetic acid), 1 mg/L NAA(Naphthyl acetic acid) and 0.5 mg/L BA(6-benzylaminopurine). A low plating density (5 x 104/ml) proved to be favourable to the division of protoplast-derived cells. The first divisioll occurred 4 days after culture, and the division frequency reached 24% at 10 days. A number of cell colonies and microcalli formed in 6 weeks. The microcalli were transferred onto MSB medium with 0.5 mg/L NAA and 0.5 mg/L BA for further proliferation. Shoot formation was initiated when the calli of 3-4 mm in size were transferred onto MSB differentiation medium with 0.1 mg/L NAA and 1 mg/L BA. The frequency of shoot formation was 35%. The shoots of 4-5 cm in height were excised from the callus and rooted on half strength MS medium with 0.5 mg/L IBA and 0.1 mg/L BA. After transplantation into pots, the regenerated plants grew vigorously in the phytotron.

Pathophysiological and clinical aspects of gastric hyperplastic polyps

Gastric polyps become a major clinical problem because of high prevalence and tendency to malignant transformation of some of them. The development of gastric hyperplastic polyps results from excessive proliferation of foveolar cells accompanied by their increased exfoliation, and they are macroscopically indistinguishable from other polyps with lower or higher malignant potential. Panendoscopy allows detection and differentiation of gastric polyps, usually after obtaining histopathological biopsy specimens. Unremoved gastric hyperplastic polyps may enlarge and sometimes spontaneously undergo a sequential progression to cancer. For this reason, gastric hyperplastic polyps larger than 5 mm in size should be removed in one piece. After excision of polyps with atypical focal lesion, endoscopic surveillance is suggested depending on histopathological diagnosis and possibility of confirming the completeness of endoscopic resection. Because of the risk of cancer development also in gastric mucosa outside the polyp, neighboring fragments of gastric mucosa should undergo microscopic investigations. This procedure allows for identification of patients who can benefit most from oncological endoscopic surveillance. If Helicobacter pylori(H. pylori) infection of the gastric mucosa is confirmed, treatment strategies should include eradication of bacteria, which may prevent progression of intestinal metaplasia. The efficacy of H. pylori eradication should be checked 3-6 mo later.