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Apoptosis is the main driver of cell death in bioreactor suspension cell cultures during the production of biopharmaceuticals from animal cell lines. It is known that apoptosis also has an effect on the quality and quantity of the expressed recombinant protein. This has raised the importance of studying apoptosis for implementing culture optimization strategies. The work here describes a novel approach to obtain near real time data on proportion of viable, early apoptotic, late apoptotic and necrotic cell populations in a suspension CHO culture using automated sample preparation in conjunction with flow cytometry. The resultant online flow cytometry data can track the progression of apoptotic events in culture, aligning with analogous manual methodologies and giving similar results. The obtained near-real time apoptosis data are a significant improvement in monitoring capabilities and can lead to improved control strategies and research data on complex biological systems in bioreactor cultures in both academic and industrial settings focused on process analytical technology applications. 相似文献
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Sabri A Hance T Leroy PD Frère I Haubruge E Destain J Compère P Thonart P 《PloS one》2011,6(4):e18847
Aphidius ervi (Hymenoptera: Braconidae) is an entomophagous parasitoid known to be an effective parasitoid of several aphid species of economic importance. A reduction of its production cost during mass rearing for inundative release is needed to improve its use in biological control of pests. In these contexts, a careful analysis of its entire development phases within its host is needed. This paper shows that this parasitoid has some characteristics in its embryological development rather complex and different from most other reported insects, which can be phylogenetically very close. First, its yolkless egg allows a high fecundity of the female but force them to hatch from the egg shell rapidly to the host hemocoel. An early cellularisation allowing a rapid differentiation of a serosa membrane seems to confirm this hypothesis. The serosa wraps the developing embryo until the first instar larva stage and invades the host tissues by microvilli projections and form a placenta like structure able to divert host resources and allowing nutrition and respiration of embryo. Such interspecific invasion, at the cellular level, recalls mammal's trophoblasts that anchors maternal uterine wall and underlines the high adaptation of A. ervi to develop in the host body. 相似文献
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Kiew-Lian Wan Saw-Peng Chong Szu-Ting Ng Martin W. Shirley Fiona M.Tomley Mohd. Sanusi Jangi 《International journal for parasitology》1999,29(12):29
A study of about 500 expressed sequence tags (ESTs), derived from a merozoite cDNA library, was initiated as an approach to generate a larger pool of gene information on Eimeria tenella. Of the ESTs, 47.7% had matches with entries in the databases, including ribosomal proteins, metabolic enzymes and proteins with other functions, of which 14.3% represented previously known E. tenella genes. Thus over 50% of the ESTs had no significant database matches. The E. tenella EST dataset contained a range of highly abundant genes comparable with that found in the EST dataset of T. gondii and may thus reflect the importance of such molecules in the biology of the apicomplexan organisms. However, comparison of the two datasets revealed very few homologies between sequences of apical organelle molecules, and provides evidence for sequence divergence between these closely-related parasites. The data presented underpin the potential value of the EST strategy for the discovery of novel genes and may allow for a more rapid increase in the knowledge and understanding of gene expression in the merozoite life cycle stage of Eimeria spp. 相似文献
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Pak Hei Chan Jo Jo Hai Esther W. Chan Wen Hua Li Hung Fat Tse Ian C. K. Wong Gregory Y. H. Lip Chung Wah Siu 《PloS one》2016,11(3)
Background
The efficacy and safety of warfarin therapy for stroke prevention in atrial fibrillation (AF) depends on the time in therapeutic range (TTR). We aimed to assess the predictive ability of SAMe-TT2R2 score in Chinese AF patients on warfarin, whose TTR is notoriously poor.Methods and Results
This is a single-centre retrospective study. Patients with non-valvular AF on warfarin diagnosed between 1997 and 2011 were stratified according to SAMe-TT2R2 score, and TTR was calculated using Rosendaal method. The predictive power of SAMe-TT2R2 scores for good TTR i.e. >70% was assessed. We included 1,428 Chinese patients (mean age 76.2±8.7 years, 47.5% male) with non-valvular AF on warfarin. The mean and median TTR were 38.2±24.4% and 38.8% (interquartile range: 17.9% and 56.2%) respectively. TTR decreased progressively with increasing SAMe-TT2R2 score (p = 0.016). When the cut-off value of SAMe-TT2R2 score was set to 2, the sensitivity and specificity to predict TTR<70% were 85.7% and 17.8%, respectively. The corresponding positive and negative predictive values were 10.1% and 92.0%. After a mean follow-up of 4.7±3.6 years, 338 patients developed an ischemic stroke (4.96%/year). Patients with TTR≥70% had a lower annual risk of ischemic stroke of 3.67%/year compared with than those with TTR<70% (5.13%/year)(p = 0.08). Patients with SAMe-TT2R2 score ≤2 had the lowest risk of annual risk of ischemic stroke (3.49%/year) compared with those with SAMe-TT2R2 score = 3 (4.56%/year), and those with SAMe-TT2R2 score ≥4 (6.41%/year)(p<0.001). There was also a non-significant trend towards more intracranial hemorrhage with increasing SAMe-TT2R2 score.Conclusions
The SAMe-TT2R2 score correlates well with TTR in Chinese AF patients, with a score >2 having high sensitivity and negative predictive values for poor TTR. Ischemic stroke risk increased progressively with increasing SAMe-TT2R2 score, consistent with poorer TTRs at high SAMe-TT2R2 scores. 相似文献69.
Objective
In Malaysia, futsal is a popular sport played by individuals across all ages and genders. Despite its popularity, information on futsal related injury in Malaysia is not available. The purpose of this study is to examine the injury incidence and injury patterns among amateur men and women futsal players in Malaysia.Methods
Players reported injury to the tournament medical team during the FELDA/FAM National Futsal League 2010 were interviewed and assessed by a Sports Medicine registrar. Player''s socio-demographic profiles and information about the injury were documented in the injury report form adapted from medical report form used by FIFA: Medical Assessment and Research Centre (F-Marc).Results
A total of 86 injuries were reported from 141 matches, equivalent to an incidence of 91.5 injuries per 1000 player hours (95% CI 72.2 to 110.8), or 61.0 injuries per 1000 player matches (95% CI 48.1 to 73.9). Most were minor injuries resulted from contact with another player. Injuries often involved the lower extremity (44%) followed by the trunk (14%) and the upper limb (13%). Ankle (n = 7; 39%) and knee (n = 6; 33%) sprains were the most prevalent diagnoses of time-loss injuries. A significant association between time-loss and type of injury was found χ 2 (1,N = 86) = 3.99, p = 0.04. In addition, time-loss injury was significantly associated with playing surface χ 2 (1,N = 86) = 10.11, p = 0.018.Conclusion
The injury rate during the FELDA/FAM National Amateur Futsal Men''s League in Malaysia was lower compared with previous Futsal World Cups competition. Most injuries resulted from contact with another player were minor and did not lead to time-loss from participation. Time-loss injury was significantly associated with type of injury and playing surface. 相似文献70.
Protoplasma - Vesicular trafficking between endoplasmic reticulum and Golgi plays a major role in the growth and proliferation of breast cancer cells. Various proteins regulate this ER-Golgi... 相似文献