杏鲍菇液体菌种的生产工艺优化与应用

对杏鲍菇液体发酵过程进行研究,实验结果表明杏鲍菇液体菌种较优生产工艺条件是：250mL三角瓶中装液量为100mL,转速180r·min^-1,温度25℃,发酵培养周期144h。所获得的杏鲍菇液体菌种活力强,菌龄一致,将其接种于木屑栽培培养基,菌丝萌发、吃料快,生长整齐,出菇早,平均生物学效率92．4％。     

LRRK2/NF-κB signaling modulates inflammatory responses in BCG-infected RAW264.7 macrophages

AIM: To investigate the biological function and potential mechanism of leucine-rich repeat kinase 2 (LRRK2) in RAW264.7 macrophages during Mycobacterium tuberculosis infection. METHODS: The bacillus Calmette-Guerin (BCG)-infected RAW264.7 cell model was established. Colony-forming unit (CFU) analysis was used to determine the mycobacterial viability. The releases of interleukin (IL)-1β, IL-6 and interferon-γ (IFN-γ) in the RAW264.7 cells were detected by ELISA. qPCR and Western blot were used to measure the mRNA and protein expression levels, respectively. RESULTS: LRRK2 was robustly enhanced in the RAW264.7 cells in response to BCG infection. Additionally, silencing of LRRK2 suppressed intracellular growth of mycobacteria during BCG challenge. Moreover, silencing of LRRK2 dramatically attenuated the accumulation of inflammatory cytokines IL-1β, IL-6 and IFN-γ induced by BCG infection. More importantly, LRRK2 modulated BCG-induced inflammatory responses by positively regulating the nuclear factor-κB (NF-κB) signaling pathway. CONCLUSION: LRRK2/NF-κB signaling pathway positively modulates inflammatory responses during BCG infection, which may provide a better understanding of the pathogenesis of tuberculosis and useful information for developing potential therapeutic interventions against the disease.     

Effects of different β-adrenergic receptors on cardiac systolic and diastolic functions in hypoxic stress rats

AIM:To explore the effects of different β-adrenergic receptors (β-AR) on the left and right ventricular systolic and diastolic functions in rats under acute hypoxic stress. METHODS:The healthy male SD rats were randomly divided into 4 groups (n=7):control group, non-selected β-AR blocker propranolol group, selected β₁-AR blocker atenolol group and selected β₂-AR blocker ICI 118,551 group, and then the rats were exposed to normoxia (20.9% O₂, 79.1% N₂) and hypoxia (15.0% O₂, 85.0% N₂) condition respectively at the altitude of 2 260 m (Xining, China). The heart rate (HR), the left ventricular systolic pressure (LVSP), the right ventricular systolic pressure (RVSP), and the maximum raise/decline rate of left and right ventricular pressure (±dp/dt_max) were monitored, and the arterial blood gas in normoxia and hypoxia condition were compared to explore the effect of β-AR on the left and right ventricular systolic and diastolic functions in acute hypoxic stress rats. RESULTS:Under normoxia condition, the LVSP, ±dp/dt_max of left ventricular were decreased in propranolol group, atenolol group and ICI 118,551 group, the RVSP and ±dp/dt_max of right ventricle were decreased in propranolol group and atenolol group (P<0.05). Under hypoxia condition, the PaO₂, LVSP, ±dp/dt_max of left ventricle were decreased in all groups compared with the normoxia group, and the ±dp/dt_max of right ventricle was increased in all groups (P<0.05), also the degree of index change in control group was more obvious than that in propranolol group and atenolol group. CONCLUSION:The activation of β₁-AR is an important compensatory regulation for heart function during hypoxic stress. However, the compensatory enhancement of right heart function under acute hypoxia condition which through tonogenic dilation is more significant for maintaining the normal circulating blood flow.     

邢台县苹果园水肥投入现状及产量差分析

以邢台县"红富士"苹果园为研究对象,通过对当地果园的养分投入类型和投入量、灌溉方式和灌溉量以及产量进行调研,评价其水肥投入水平,并基于Boundary line分析法,探索该地区苹果园最高产量下的最佳养分施用量,以期明确邢台县苹果园水肥投入现状及最高产量水平下最佳养分投入量。结果表明:邢台县苹果园无机肥投入量较高,有机肥投入不足,无机肥N、P_2O5、K_2O平均投入量分别为825、460、692kg·hm~(-2),有机肥仅为177、138、100kg·hm~(-2);有机肥施用率较低,仅占调查总数的27.35%,且施用种类繁多,鸡粪、羊粪及商品有机肥三者总计占比达95.61%。灌溉方式以漫灌、沟灌为主,二者合计占比达93.70%,滴灌仅为6.30%;生长季内灌溉次数多为3~4次;与滴灌相比,漫灌和沟灌单次灌水量分别多用140%、100%。Boundary line模型分析显示,邢台县苹果园最高产量水平下N、P_2O5、K_2O投入量分别为616.50、371.90、553.10kg·hm~(-2),对产量的贡献分别为28.00%、17.60%、22.60%。总之,邢台县苹果园养分投入量较高,轻有机重无机,肥料投入种类繁多,漫灌和沟灌为其主要灌溉方式,水资源浪费严重。     

Marc145细胞源EDC3基因的克隆及其生物信息学分析

为获得Marc145细胞源EDC3基因序列,分析其序列特征及编码蛋白的结构和功能,本试验采用RT-PCR方法从Marc145细胞中扩增EDC3基因,并进行克隆和序列测定;应用DNAStar软件分析该基因的核苷酸和氨基酸序列,与参考序列经BLAST比对后分析同源性,并构建系统进化树;利用生物信息学方法对其编码区蛋白进行二级结构、三级结构、B细胞表位、跨膜结构域和信号肽预测。结果显示,Marc145细胞源EDC3基因长度为1 527 bp,共编码507个氨基酸;EDC3基因编码区核苷酸序列与绿猴、猕猴、狒狒、人、倭黑猩猩、马、野猪、虎鲸、绵羊、非洲象和大熊猫的同源性在91.5%~99.2%之间,与非哺乳动物原鸡同源性最低,仅为81.2%;EDC3氨基酸序列与上述物种的同源性在95.3%~99.6%之间,与原鸡的同源性仅为88.8%。系统进化树结果显示,Marc145细胞源EDC3基因与绿猴的亲缘关系最近,其次是灵长类。蛋白结构预测结果表明,EDC3蛋白主要由α-螺旋和无规则卷曲组成,分别为23.38%和47.35%,二级结构与三级结构预测结果相符。该蛋白存在多个B细胞优势抗原表位,无跨膜结构域及信号肽区域。本试验结果可为Marc145细胞源EDC3基因功能的进一步研究提供参考。     

瘤胃源益生菌对小鼠生长和生理特性的影响

试验旨在对筛选出的6种瘤胃源益生菌进行小鼠试验,以期为其在畜禽养殖业的进一步开发和利用提供参考依据。选取5周龄雄性昆明小鼠56只,随机分为7组：生理盐水对照组、解淀粉芽孢杆菌Lw-J21组、枯草芽孢杆菌Lw-K16组、乳酸菌Lw-R35组、产蛋白酶菌Lw-D48组、产纤维素酶菌Lw-X21组和酵母菌Lw-JM70组,试验组每天以0.2 mL/10 g体重剂量连续灌胃42 d,对照组灌喂相同剂量的生理盐水,比较并分析灌胃不同益生菌对小鼠体重、肠道菌群数量、脂肪积累量、免疫器官指数和血糖降解能力等的影响。结果显示,与对照组相比,解淀粉芽孢杆菌Lw-J21和产纤维素酶菌Lw-X21组小鼠体重增加明显（P>0.05）,同时可显著减少小鼠体内的脂肪积累（P<0.05）。乳酸菌Lw-R35和产纤维素酶菌Lw-X21组小鼠肠道中的乳酸菌和总厌氧菌数量均显著或极显著增多（P<0.05;P<0.01）。各益生菌组小鼠脾脏指数和胸腺指数均有显著或极显著提高（P<0.05;P<0.01）,且可不同程度提高小鼠血糖的调节能力。综上所述,用筛选出的6种天然益生菌饲喂小鼠可改善其肠道微生态环境、免疫器官指数和血糖调节能力等。     

So much for the city: Urban–rural song variation in a widespread Asiatic songbird

Song plays a fundamental role in intraspecific communication in songbirds. The temporal and structural components of songs can vary in different habitats. These include urban habitats where anthropogenic sounds and alteration of habitat structure can significantly affect songbird vocal behavior. Urban–rural variations in song complexity, song length and syllable rate are not fully understood. In this study, using the oriental magpie‐robin (Copsychus saularis) as a model, we investigated urban–rural variation in song complexity, song length, syllable rate, syllable length and inter‐syllable interval. Comparing urban and rural songs from 7 countries across its natural Asiatic range (Bangladesh, India, Malaysia, Nepal, Singapore, Sri Lanka and Thailand), we found no significant differences in oriental magpie‐robin song complexity. However, we found significant differences in temporal song variables between urban and rural sites. Longer songs and inter‐syllable intervals in addition to slower syllable rates within urban sites contributed the most to this variance. This indicates that the urban environment may have driven production of longer and slower songs to maximize efficient transmission of important song information in urban habitats.     

Expression and significance of miR-193b in cervical cancer

AIM: To investigate the expression of microRNA-193b(miR-193b) in the cervical tissues, and further to explore the effect of silencing miR-193b on diamminedichloroplatinum(DDP)-treated HeLa cell viability. METHODS: The expression levels of miR-193b in different cervical tissues were examined by qPCR. After transfection of miR-193b-inhibitor, the cell migration was determined by Transwell assay, the sensitivity of HeLa cells to DDP was measured by MTT assay, the protein levels of phosphate and tension homology deleted on chromsome ten(PTEN), protein kinase B(Akt), p-Akt and p-glycoprotein(P-gp) were determined by Western blot. RESULTS: The mRNA level of miR-193b was significantly increased in the cervical cancer tissues compared with normal cervical tissues(P<0.05). Knockdown of miR-193b obviously inhibited migration and enhanced sensitivity to DDP of HeLa cells(P<0.05). Additionally, after transfection of miR-193b-inhibitor, the expression of PTEN was increased, whereas the protein levels of p-Akt and P-gp were decreased(P<0.05). CONCLUSION: miR-193b is highly expressed in the cervical cancer tissues. Inhibition of miR-193b augments the sensitivity to DDP of HeLa cells, at least in part, through PTEN-PI3K/Akt signaling pathway.     

Intervention effects of apyrase on silica-induced pulmonary fibrosis in mice

AIM: To investigate the effect of apyrase on the experimental silicosis. METHODS: C57BL/6 male mice were randomly divided into control group, silica treatment group, silica+apyrase group and silica+NS group. A mouse model of lung fibrosis was induced by crystalline silica particles (50 mg/kg, via oropharyngeal instillation), and were sacrificed at 3 h, 7 d, 14 d and 28 d. Apyrase was delivered by oropharyngeal aspiration at the same time and 4 h after silica challenge. The lung indexes were calculated and the concentration of ATP was detected by bioluminescent assay. The mRNA expression levels of collagen type Ⅰ(Col Ⅰ), collagen type Ⅲ (Col Ⅲ) and transforming growth factor β1 (TGF-β1) were examined by real-time PCR. The protein levels of TGF-β1 in bronchoalveolar lavage fluid were measured by ELISA. RESULTS: The elevated lung index and collagen levels showed that silicosis model was established successfully. Compared with silica group, apyrase treatment significantly alleviated silica-induced inflammation, reduced inflammation score on day 7, and decreased the lung index, collagen volume fraction and the mRNA expression of Col Ⅰand Col Ⅲ on day 28. Treatment with apyrase effectively down-regulated the mRNA levels of TGF-β1 in the lung tissues and TGF-β1 protein levels in bronchoalveolar lavage fluid on day 7.CONCLUSION: Apyrase attenuates the pulmonary inflammation and fibrosis of silicosis, which may be related with down-regulation of ATP and TGF-β1 in the lung tissues.     

Regulatory effects of spirolactone on SiO2-induced lung macrophage subtype switching

AIM: To investigate the influence of spirolactone (SPI) on mouse pulmonary macrophage subtype switching induced by silicon dioxide (SiO₂). METHODS: C57BL/6 mice were divided into normal saline (NS) group, SiO₂ group, SiO₂+SPI group and SiO₂+NS group. A mouse model of silicosis was developed with crystalline SiO₂ particles (40 mg/kg, via oropharyngeal instillation). SPI (20 mg/kg) or (NS) was delivered daily by oral gavage after SiO₂ administration. The mice were sacrificed on days 3, 14 and 28. Alveolar washing, total cell counting, differential cell counting and flow cytometry analysis were performed. The right lower lobe of lavaged lungs was collected to prepare single-cell suspension for flow cytometry analysis. RESULTS: Compared with SiO₂ group, SPI treatment significantly alleviated SiO₂-induced inflammatory cell accumulation in brochoalveolar lavage fluid on day 3 and 14. Compared with NS group, the M1 alveolar macrophages and M1 pulmonary interstitial macrophages in SiO₂ group switched to M2 subtype dramatically, while SPI treatment reversed the switching effectively.CONCLUSION: SPI treatment alleviates SiO₂-induced inflammatory cell accumulation, which may be related to reversing macrophage subtype switching.