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1.
An efficient mammalian cell system for producing bioproducts should retain high cell viability and efficient use of energy sources rendering the need to understand the effects of various variables on the cell system. In this study, global metabolite (metabolomics) analysis approach was used to try and understand the relationships between types of media used, culture growth behavior and productivity. CHO-KI cells producing IGF-1 were obtained from ATCC and grown in T-flask (37 °C, 5 % CO2) until 70–80 % confluent in RPMI 1640 and Ham’s F12, respectively. Samples were taken at 8-hourly intervals for routine cell counting, biochemical responses, insulin like growth factor—1 (IGF-1) protein concentration and global metabolite analysis (gas chromatography mass spectrometry, GCMS). Conditioned media from each time point were spun down before injection into GCMS. Data from GCMS were then transferred to SIMCA-P + Version 12 for chemometric evaluation using principal component analysis. The results showed that while routine analysis gave only subtle differences between the media, global metabolite analysis was able to clearly separate the culture based on growth media with growth phases as confounding factor. Different types of media also appeared to affect IGF-1 production. Asparagine was found to be indicative of healthiness of cells and production of high IGF-1. Meanwhile identification of ornithine and lysine in death phase was found to be associated with apoptosis and oversupplied nutrient respectively. Using the biomarkers revealed in the study, several bioprocessing strategies including medium improvement and in-time downstream processing can be potentially implemented to achieve efficient CHO culture system.  相似文献   

2.
The connections between biological sciences, art and printed images are of great interest to the author. She reflects on the historical relevance of visual representations for science. She argues that the connection between art and science seems to have diminished during the twentieth century. However, this connection is currently growing stronger again through digital media and new imaging methods. Scientific illustrations have fuelled art, while visual modeling tools have assisted scientific research. As a print media artist, she explores the relationship between art and science in her studio practice and will present this historical connection with examples related to evolution, microbiology and her own work. Art and science share a common source, which leads to scrutiny and enquiry. Science sets out to reveal and explain our reality, whereas art comments and makes connections that don’t need to be tested by rigorous protocols. Art and science should each be evaluated on their own merit. Allowing room for both in the quest to understand our world will lead to an enriched experience.  相似文献   

3.
Because M. bovis otitis media is an economically important problem, there is a need to understand the pathogenesis of disease, not only to improve our understanding of the factors contributing to the development of this disease but also to inform the development of improved diagnostic tests and therapy. Oral ingestion of M. bovis-contaminated milk is linked, but not definitively proven, to development of otitis media. In the current study, we demonstrate that oral ingestion of M. bovis infected colostrum can result in an ascending infection and development of otitis media. Importantly, M. bovis was found to have a previously unrecognized tendency for colonization of the tonsils of calves, which most likely contributed to the subsequent development of otitis media. In contrast, transtracheal inoculation failed to produce clinically significant upper respiratory tract disease, although did induce lower respiratory tract disease. The upper respiratory tract was the major site of M. bovis-specific B cell and mucosal IgA responses in calves inoculated by the oral route. The oral inoculation route of infection presented here is particularly suited to the study of host-pathogen interactions during initial colonization of the tonsils, expansion of infection and dissemination to the lower respiratory tract and middle ear. In addition, it could be used to investigate potential new preventative or control strategies, especially those aimed at limiting colonization of the tonsils and/or spread to the middle ear.  相似文献   

4.
This paper describes our attempt to devise a short text aimed at improving students' understanding of gas resorption in body cavities. Students are expected to understand the mechanisms behind paranasal sinusitis, otitis media, closed pneumothorax, and atelectasis of collapsed lung tissue, all used as examples. On the basis of the interpretation that during pneumothorax resorption, gas diffuses down pressure gradients into the blood, students are encouraged to calculate tables of pressure gradients for the above-mentioned pathological conditions. After answering a few questions, students need to analyze and eventually accept the following conclusion: in cases of air trapping in collapsible body cavities, all gases will be fully reabsorbed without pain. Air trapping in bone cavities leads only to partial reabsorption of gases and results in subatmospheric intracavity pressure. Partial vacuum causes painful mucosal edema and free fluid secretion.  相似文献   

5.
Social media is growing as a technological and social phenomenon, with billions of people using it every day around the world. Given its increasing ubiquity, researchers continue to seek to understand social media and its implications for the social world. Part of the growing body of scholarship on social media includes uncovering the most effective methodologies for exploration that appropriately consider differences between the technology of social media and the ways in which people use them. New directions for social media research include the use of big data and analysing the socio-technical nature of social media. Using data from an ongoing study on college Millennials that includes questions about their thoughts on the Black Lives Matter movement, the author suggests another direction for future research: studying the implications of social media as an informational source.  相似文献   

6.
道德规范教育如今已经提升到了专业的水平。因此在专业领域里 (例如工程学和医学 ) ,道德规范教育应作为必修课程。但至今很多理科课程仍没有把它列为必修课。这就给我们提出了一个疑问 :理科是专业课程吗 ?如果是的话 ,那么科学家例如动物学家需不需要熟悉他们职责范围内的道德准则和尺度呢 ?动物学家对医学上暴露的一些问题很敏感———包括我们怎样对待动物以及我们怎样或者是否开展基因工程。但是从道德观念上来看 ,道德规范教育的实行是比这两件事更实际的。这篇论文就以上观点进行了进一步的论述 ,并且对把道德规范教育加入理科课程的需求和可能性做了评估。在现实社会里 ,动物科学家是被敬重的专业人士。他们每天面对着许多极可能影响我们生活环境的决策。有鉴于此 ,动物科学家必需掌握道德规范的标准 ,并且有能力做出与此相符合的决策。这才能使我们在动物学的教学过程中确保动物学家持续稳定的专业发展方向  相似文献   

7.
We used formative research to assess the information needs and information-seeking strategies with general public audience segments in response to a hypothetical attack using plague, and we pretested informational materials about plague. Twelve focus groups were conducted across the country, with 129 individuals being purposively sampled by ethnicity and place of residence. Across groups, participants wanted to understand: the nature of the threat of plague, how to protect themselves from transmission, how to detect exposure and symptoms, how to treat infection, and progress in apprehending perpetrators. Participants reported that they would seek information from both the news media and local authorities. Based on the findings and the challenges posed by a terrorist attack using plague, the authors recommend that message materials answer key questions, provide clear action steps, be clear and easily understood, include sources for credibility, and reflect full government disclosure. A dissemination plan is required to ensure that critical information will be available when people need it and where they look.  相似文献   

8.
Perfusion is a cell culture mode that is gaining popularity for the manufacture of monoclonal antibodies and their derivatives. The cell culture media supporting perfusion culture need to support higher cell densities than those used in fed-batch culture. Therefore, when switching from a fed-batch to a perfusion mode, a new medium need to be developed which supports high cell densities, high productivity, and favorable product quality. We have developed a method for deriving perfusion culture media based on existing fed-batch media and feeds. We show that we can obtain culture media that successfully support perfusion cultures in a single-use rocking bioreactor system at cell-specific perfusion rates below 25 pL−1 cell−1 day−1. High productivities and favorable product quality are also achievable.  相似文献   

9.
Biological Trace Element Research - We have studied solid waste incinerator ashes to understand the leaching mechanism and speciation of toxic and other elements in them. Leaching media, such as...  相似文献   

10.
While we often assume media are highly effective tools for learning, research shows an unpredictable relationship between text and audience response, with variable interpretation being the norm. This can be especially problematic in anthropology, whose central goal is to understand different cultures; some studies suggest that films may reinforce ethnocentrism, especially if used without framing or analysis. We report on a project that studied student responses to media, offering practical guidelines for effective use in the classroom.  相似文献   

11.
新媒体的出现契合了公众生活方式转变的需求,为医院文化建设与发展带来新的契机与平台。探索应用新媒体能够丰富医院文化内涵,塑造良好的医院形象,提升医院竞争力,进而推进医院发展。  相似文献   

12.
Buffering complex growth media with inorganic or organic phosphates increased the resistance levels of lactic streptococci to aminoglycoside antibiotics, whereas it increased their sensitivity to erythromycin, penicillin, and tetracycline. The results suggest the need for caution in the selection of media for testing the antibiotic sensitivity of lactic streptococci.  相似文献   

13.
The issue of human reproductive cloning has recently received a great deal attention in public discourse. Bioethicists, policy makers, and the media have been quick to identify the key ethical issues involved in human reproductive cloning and to argue, almost unanimously, for an international ban on such attempts. Meanwhile, scientists have proceeded with extensive research agendas in the cloning of animals. Despite this research, there has been little public discussion of the ethical issues raised by animal cloning projects. Polling data show that the public is decidedly against the cloning of animals. To understand the public's reaction and fill the void of reasoned debate about the issue, we need to review the possible objections to animal cloning and assess the merits of the anti-animal cloning stance. Some objections to animal cloning (e.g., the impact of cloning on the population of unwanted animals) can be easily addressed, while others (e.g., the health of cloned animals) require more serious attention by the public and policy makers.  相似文献   

14.
The response of wall stress to the elasticity of each layer in the aorta wall was investigated to understand the role of the different elastic properties of layers in the aortic dissection. The complex mechanical interaction between blood flow and wall dynamics in a three-dimensional arch model of an aorta was studied by means of computational coupled fluid-structure interaction analysis. The results show that stresses in the media layer are highest in three layers and that shear stress is concentrated in the media layer near to the adventitia layer. Hence, the difference in the elastic properties of the layers could be responsible for the pathological state in which a tear splits across the tunica media to near to the tunica adventitia and the dissection spreads along the laminar planes of the media layer where it is near the adventitia layer.  相似文献   

15.
Wendler D  Grady C 《Bioethics》2008,22(4):203-208
To give valid informed consent to participate in clinical research, potential participants should understand the risks, potential benefits, procedures, and alternatives. Potential participants also should understand that they are being invited to participate in research. Yet it is unclear what potential participants need to understand to satisfy this particular requirement. As a result, it is unclear what additional information investigators should disclose about the research; and it is also unclear when failures of understanding in this respect undermine the validity of potential participants' informed consent. An analysis of individuals' interests suggests that potential participants need to understand three additional facts to understand that they are being invited to participate in research: 1) research contribution : those who enroll in the study will be contributing to a project designed to gather generalizable knowledge to benefit others in the future; 2) research relationship : the investigators will rely on participants' efforts to gather the generalizable knowledge to benefit others; and 3) research impact : the extent to which participating in the study will alter what participants do and what happens to them.  相似文献   

16.
检测不同培养基条件下,放线菌TRM10325发酵液抑制群感效应的活性,初步了解其活性稳定性,并为筛选最优发酵培养基提供实验依据。选取17种合成培养基、26种天然培养基发酵放线菌TRM10325,采用微孔板半定量法检测其对紫色素杆菌群感效应以及表皮葡萄球菌生物膜形成的抑制作用。不同配方的培养基对放线菌10325抑制群感效应活性的影响也不相同,其中Am6培养基抑制群感效应效果最佳。成分不同的培养基,明显影响微生物不同次级代谢产物的产生。同一微生物在不同培养基中发酵,其次生代谢产物的种类和含量变化很大。最终选定Am6培养基为最适发酵培养基。  相似文献   

17.
The elastic properties of the thoracic aorta are well known, but this is the first study of the inherent strength of the tunica media. The latter is crucial to understand how dissecting aneurysms occur. Pressure-volume (P-V) measurements were recorded as a dilute suspension of India ink was infused into the tunica media using a constant flow pump (0.21 or 0.88 ml min-1) attached to a 20 G needle inserted into the media. Tests done on 31 opened pig upper descending thoracic aortas showed the peak pressure to tear the media averaged 77.2 +/- 1.5 kPa (579 mm Hg). The initial slope of the P-V curve revealed the average distensibility of the media of 3.02 +/- 0.28 (MPa)-1. The work per unit area of tissue required to propagate a tear in the aorta was 15.9 +/- 0.9 mJ cm-2. These values were independent of the tear depth at the 95% confidence interval.  相似文献   

18.
The effects of concentrated fibroblast-conditioned media were tested to determine whether hepatocyte function can be maintained without direct contact between hepatocytes and fibroblasts. Primary rat hepatocytes cultured with a concentrated conditioned media of NIH-3T3 J2 cell line (final concentration of 55 mg/ml) showed significantly improved survival and functions (albumin and urea) compared to those of control groups. They also showed higher expression levels of mRNA, albumin and tyrosine aminotransferase compared to hepatocyte monoculture. The results suggest that culture with concentrated fibroblast-conditioned media could be an easy method for in vitro maintenance of primary hepatocytes. They also could be contribute to understand and analyze co-culture condition of hepatocyte with stroma cells.  相似文献   

19.
Development of protocols and media for culturing immune cells from marine invertebrates has not kept pace with advancements in mammalian immune cell culture, the latter having been driven by the need to understand the causes of and develop therapies for human and animal diseases. However, expansion of the aquaculture industry and the diseases that threaten these systems creates the need to develop cell and tissue culture methods for marine invertebrates. Such methods will enable us to better understand the causes of disease outbreaks and to develop means to avoid and remedy epidemics. We report a method for the short-term culture of phagocytes from the purple sea urchin, Strongylocentrotus purpuratus, by modifying an approach previously used to culture cells from another sea urchin species. The viability of cultured phagocytes from the purple sea urchin decreases from 91.6% to 57% over six days and phagocyte morphology changes from single cells to aggregates leading to the formation of syncytia-like structures. This process is accelerated in the presence of lipopolysaccharide suggesting that phagocytes are capable of detecting this molecular pattern in culture conditions. Sea urchin immune response proteins, called Sp185/333, are expressed on the surface of a subset of phagocytes and have been associated with syncytia-like structures. We evaluated their expression in cultured phagocytes to determine their possible role in cell aggregation and in the formation of syncytia-like structures. Between 0 and 3 hr, syncytia-like structures were observed in cultures when only ∼10% of the cells were positive for Sp185/333 proteins. At 24 hr, ∼90% of the nuclei were Sp185/333-positive when all of the phagocytes had aggregated into syncytia-like structures. Consequently, we conclude that the Sp185/333 proteins do not have a major role in initiating the aggregation of cultured phagocytes, however the Sp185/333 proteins are associated with the clustered nuclei within the syncytia-like structures.  相似文献   

20.
Edward Llewellyn Thomas 《CMAJ》1966,94(15):808-811
The good physician of the future will need to master not only the basic and traditional medical skills but many new concepts and techniques as well. He will need to be, as always, a compassionate and intelligent man. If he is to retain his status as a healer in the eyes of his patients, he will have to be fully aware of what is happening in the social and technological environment, or he will run the risk of being relegated to the position of a high-grade technician.He will have new physical tools and new thinking tools to help him. To understand and use these, and also to understand the technical world of the future, he will need a sound knowledge of the physical sciences and some fluency in the language of modern mathematics.  相似文献   

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