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《Current biology : CB》2022,32(3):645-653.e8
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3.
The major developments in the field of nuclear activation analysis, from 1936 to 1989, are discussed. The developments are
grouped into five consecutive time periods. The impact of various scientists on the development of the field in the first
35 years is also discussed. 相似文献
4.
Ying-Ying Li Xi Chen Jin-Xian Yang Qiang Chen Tie-Ying Song Jun-Qing Ge 《Journal of fish biology》2023,102(1):141-154
Eels are important aquaculture species for which an increasing number of reference genes are being identified and applied. In this study, five housekeeping genes [RPL7 (ribosomal protein L7), 18 S (18 S ribosomal RNA), EF1A (elongation factor 1α), ACTB (β-actin) and GAPDH (glyceraldehyde-3-phosphate dehydrogenase)] were chosen to evaluate their reliability as reference genes for quantitative real-time PCR (qPCR) for the study of Anguilla anguilla. The expression of the selected genes in different eel tissues was determined using qPCR at different growth stages or upon challenge by Anguillid herpesvirus (AngHV), and the expression levels of these genes were then compared and evaluated using the geNorm and NormFinder algorithms. Then, RefFinder was used to comprehensively rank the examined housekeeping genes. Interestingly, the expression of the evaluated housekeeping genes exhibited tissue-dependent and treatment-dependent variations. In different growth periods A. anguilla tissues, the most stable genes were the following: ACTB in mucus; 18 S in skin and kidney; RPL7 in muscle, gill, intestine and brain; EF1A in heart and liver; and GAPDH in spleen. In contrast, in AngHV-challenged A. anguilla tissues, the most stable genes were the following: 18 S in mucus; RPL7 in skin, gill, heart, spleen, kidney and intestine; EF1A in muscle and liver; and ACTB in brain. Further comparison analysis indicated that the expression of RPL7 and EF1A was stable in multiple A. anguilla tissues in different growth periods and in eels challenged by AngHV. Nonetheless, the expression level of GAPDH in eel tissues was lower, and it was unstable in several tissues. These results indicated that the selection of reference genes for qPCR analysis in A. anguilla should be made in accordance with experimental parameters, and both RPL7 and EF1A could be used as reference genes for qPCR study of A. anguilla at different growth stages or upon challenge by AngHV. The reference genes identified in this study could improve the accuracy of qPCR data and facilitate further studies aimed at understanding the biology of eels. 相似文献
5.
Thomas Schiewe Björn Gutschmann Lara Santolin Saskia Waldburger Peter Neubauer Roland Hass Sebastian L. Riedel 《Biotechnology and bioengineering》2023,120(10):2880-2889
An efficient monitoring and control strategy is the basis for a reliable production process. Conventional optical density (OD) measurements involve superpositions of light absorption and scattering, and the results are only given in arbitrary units. In contrast, photon density wave (PDW) spectroscopy is a dilution-free method that allows independent quantification of both effects with defined units. For the first time, PDW spectroscopy was evaluated as a novel optical process analytical technology tool for real-time monitoring of biomass formation in Escherichia coli high-cell-density fed-batch cultivations. Inline PDW measurements were compared to a commercially available inline turbidity probe and with offline measurements of OD and cell dry weight (CDW). An accurate correlation of the reduced PDW scattering coefficient µs′ with CDW was observed in the range of 5–69 g L−1 (R2 = 0.98). The growth rates calculated based on µs′ were comparable to the rates determined with all reference methods. Furthermore, quantification of the reduced PDW scattering coefficient µs′ as a function of the absorption coefficient µa allowed direct detection of unintended process trends caused by overfeeding and subsequent acetate accumulation. Inline PDW spectroscopy can contribute to more robust bioprocess monitoring and consequently improved process performance. 相似文献
6.
《Current biology : CB》2020,30(18):3522-3532.e6
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7.
本研究建立了一种基于Taqman-MGB探针的亚稀褶红菇Russula subnigricans实时荧光定量PCR检测方法。根据亚稀褶红菇与其近似种的内转录间隔区(internal transcribed spacers,ITS)序列差异,设计合成1对引物和1条特异性Taqman-MGB探针,并用常见有毒红菇种类进行验证。结果显示,引物特异性良好,仅亚稀褶红菇出现荧光信号,完成整个检测过程只需2h。该法能够为毒蘑菇中毒的快速检测提供技术支持。 相似文献
8.
《Animal : an international journal of animal bioscience》2020,14(7):1438-1446
Slow-release urea (SRU) can substitute dietary protein sources in the diet of feedlotting ruminant species. However, different SRU structures show varying results of productive performance. This study was conducted to investigate the effect of different sources of nitrogen on performance, blood parameter, ruminal fermentation and relative population of rumen microorganisms in male Mehraban lambs. Thirty-five male lambs with an average initial BW of 34.7 ± 1.8 kg were assigned randomly to five treatments. Diets consisted of concentrate mixture and mineral and vitamin supplements plus (1) alfalfa and soybean meal, (2) wheat straw and soybean meal, (3) wheat straw and urea, (4) wheat straw and Optigen® (a commercial SRU supplement) and (5) wheat straw and SRU produced in the laboratory. No statistical difference was observed in animal performance and DM intake among treatments. The mean value of ruminal pH and ammonia was higher (P < 0.05) for the SRU diet compared with WU diet. The difference in pH is likely to be due to the higher ammonia level as VFAs concentrations were unchanged. The level of blood urea nitrogen (BUN) was different among treatments (P = 0.065). The highest concentration of BUN was recorded in Optigen diet (183.1 mg/l), whereas the lowest value was recorded in wheat straw-soybean meal diet (147 mg/l). The amount of albumin and total protein was not affected by the treatments. The relative population of total protozoa, Fibrobacter succinogenes, Ruminococcus flavefaciens and Ruminococcus albus in the SRU treatment was higher (P < 0.01) than that in urea treatment at 3 h post-feeding. During the period of lack of high-quality forage and in order to reduce dietary costs, low-quality forage with urea sources can be used in the diet. Results of microbial populations revealed that SRU can be used as a nitrogen source which can sustainably provide nitrogen for rumen microorganism without negative effects on the performance of feedlotting lambs. 相似文献
9.
《Animal : an international journal of animal bioscience》2020,14(8):1724-1732
The endocannabinoid system (ECS) controls feed intake and energy balance in nonruminants. Recent studies suggested that dietary management alters the expression of members of the ECS in the liver and endometrium of dairy cows. The aim of this study was to determine the relationship between body condition score (BCS) loss and the mRNA abundance of genes related to fatty acid metabolism and the ECS in the subcutaneous adipose tissue (AT) of dairy cows. The BCS was determined in multiparous (3.2 ± 0.5 lactations) Holstein cows at −21 and 42 days relative to calving (designated as d = 0). Cows were grouped into three categories according to BCS loss between both assessments as follows: (1) lost ≤0.25 unit (n = 8, low BCS loss (LBL)), (2) lost between 0.5 and 0.75 units (n = 8, moderate BCS loss (MBL)) and (3) lost ≥1 unit (n = 8, high BCS loss (HBL)). Concentrations of haptoglobin and non-esterified fatty acids (NEFAs) were determined in plasma. Real-time PCR was used to determine mRNA abundance of key genes related to fatty acid metabolism, inflammation and ECS in AT. Milk yield (kg/day) between week 2 and 6 post-calving was greater in the LBL group (49.4 ± 0.75) compared to MBL (47.9 ± 0.56) and HBL (47.4 ± 0.62) groups (P < 0.05). The overall mean plasma haptoglobin and NEFA concentrations were greater in MBL and HBL groups compared with the LBL group (P < 0.05). The mRNA abundance of TNF-α, Interleukin-6 (IL-6) and IL-1β was greatest at 21 and 42 days post-calving in HBL, intermediate in MBL and lowest in LBL groups, respectively. Cows in the HBL group had the greatest AT gene expression for carnitine palmitoyltransferase 1A, hormone sensitive lipase and adipose triglyceride lipase at 21 and 42 days post-calving (P < 0.05). Overall, mRNA abundance for very long chain acyl-CoA dehydrogenase and peroxisome proliferator-activated receptor gamma, which are related to NEFA oxidation, were greater in MBL and HBL groups compared to the LBL group at 42 days post-calving. However, mRNA abundance of fatty acid amide hydrolase was lower at 21 and 42 days post-calving in HBL cows than in LBL cows (P < 0.05). In summary, results showed a positive association between increased degree of BCS loss, inflammation and activation of the ECS network in AT of dairy cows. Findings suggest that the ECS might play an important role in fatty acid metabolism, development of inflammation and cow’s adaptation to onset of lactation. 相似文献
10.
催乳素受体通过结合催乳素,能调节鱼体渗透压。为研究催乳素受体1(PRLR1)在高盐水体和低盐水体中对军曹鱼(Rachycentron canadum)的渗透调节作用,利用cDNA末端快速扩增(RACE-PCR)技术,获得了军曹鱼PRLR1全长cDNA序列。该基因全长为2629 bp,包含1953 bp的开放阅读框ORF,可编码650个氨基酸。氨基酸序列包含了2个纤维连接蛋白3型结构域(FN3)、保守的WS区和box1。采用qRT-PCR技术,检测不同盐度(10‰、30‰和35‰)条件下鳃、肠、体肾中PRLR1基因mRNA表达情况。结果显示,PRLR1基因在军曹鱼的各个组织中均有表达,其中鳃表达量最高,其次是肌肉、体肾和肠,而在胃、脾、脑和心脏中则微量表达。低盐组、正常组和高盐组中,PRLR1基因的表达量均为鳃最高;肠次之;体肾最低。随着盐度提高,PRLR1基因的鳃、肠和体肾组织表达量变化规律均呈逐步下降趋势。以上结果反映了军曹鱼PRLR1在渗透压器官中的功能差异性,说明PRLR1在军曹鱼渗透压调节上具有重要作用。 相似文献