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71.
Danilo S. Catelli Mariska Wesseling Ilse Jonkers 《Computer methods in biomechanics and biomedical engineering》2019,22(1):21-24
Most musculoskeletal models (MSKM) are designed to evaluate gait and running, which have limited range of motion (ROM). The purpose of this study was to examine the effect of wrapping surfaces (WS) at the knee and hip joints in a MSKM, on the muscle moment arms (MA) and activations during squatting. The MSKM was then customized by changing parameters of the original WS and by implementing additional WS. The WS prevent muscles from crossing into the bones, providing realistic muscle MA for large ROM. The modified MSKM is suitable for analysis up to 138° hip and 145° knee flexions. 相似文献
72.
Beaz Hidalgo R Cleenwerck I Balboa S De Wachter M Thompson FL Swings J De Vos P Romalde JL 《Systematic and applied microbiology》2008,31(3):215-222
The aim of the present study was to characterize and identify vibrios isolated from cultured clams in Galicia (NW Spain). A total of 759 isolates were obtained, phenotypically characterized, grouped and assigned to the genus Vibrio. Subsequently, the genomic diversity of 145 representative strains was analyzed by means of amplified fragment length polymorphism (AFLP), which revealed a high genetic diversity amongst these isolates. Only 57 out of 145 strains could be identified to the species level, and they were distributed in 13 AFLP clusters. V. cyclitrophicus, V. splendidus and V. alginolyticus were the most abundantly represented species. Eighty-eight isolates remained unidentified, 59 were distributed over 16 clusters, while 29 were unclustered. Sequencing of the 16S rRNA and two house-keeping genes (rpoA and recA) from representative strains belonging to eight unidentified clusters with the highest number of isolates confirmed their assignation to the Vibrionaceae family, and some of these probably represent new species within the genus. The present study confirmed that the phenotypic characterization of vibrios is not sufficient to identify them at the species level. A wide diversity of vibrios was found in cultured clams from all four geographic locations analyzed. In total, more than 12 Vibrio species and at least three potential new species in this genus were identified. 相似文献
73.
Saskia J. te Velde Amika Singh Mai Chinapaw Ilse De Bourdeaudhuij Natasa Jan Eva Kovacs Elling Bere Froydis N. Vik Bettina Bringolf-Isler Yannis Manios Luis Moreno Johannes Brug 《PloS one》2014,9(11)
Objective
To design interventions that target energy balance-related behaviours, knowledge of primary schoolchildren''s perceptions regarding soft drink intake, fruit juice intake, breakfast consumption, TV viewing and physical activity (PA) is essential. The current study describes personal beliefs and attitudes, home- and friend-related variables regarding these behaviours across Europe.Design
Cross-sectional study in which personal, family and friend -related variables were assessed by validated questionnaires, and dichotomized as favourable versus unfavourable answers. Logistic regression analyses were conducted to estimate proportions of children giving unfavourable answers and test between-country differences.Setting
A survey in eight European countries.Subjects
A total of 7903 10–12 year old primary schoolchildren.Results
A majority of the children reported unfavourable attitudes, preferences and subjective norms regarding soft drink, fruit juice intake and TV viewing accompanied with high availability and accessibility at home. Few children reported unfavourable attitudes and preferences regarding breakfast consumption and PA. Many children reported unfavourable health beliefs regarding breakfast consumption and TV viewing. Substantial differences between countries were observed, especially for variables regarding soft drink intake, breakfast consumption and TV viewing.Conclusion
The surveyed children demonstrated favourable attitudes to some healthy behaviours (PA, breakfast intake) as well as to some unhealthy behaviours (soft drink consumption, TV viewing). Additionally, many children across Europe have personal beliefs and are exposed to social environments that are not supportive to engagement in healthy behaviours. Moreover, the large differences in personal, family and friend-related variables across Europe argue for implementing different strategies in the different European countries. 相似文献74.
Glutathione half-cell reduction potential: A universal stress marker and modulator of programmed cell death? 总被引:2,自引:0,他引:2
The elucidation of factors that contribute to cell viability loss is presently compromised by the lack of a universal measure that quantifies “stress.” We have investigated mechanisms of viability loss in plant seeds to find a reliable marker of stress response. Oxidative damage has previously been correlated with degenerative processes and death, but how exactly this contributes to viability loss is unknown. We show in four species subjected to ageing or desiccation that seed viability decreased by 50% when the half-cell reduction potential of glutathione (EGSSG/2GSH), a major cellular antioxidant and redox buffer, increased to −180 to −160 mV. We then conducted a metaanalysis of data representative of 13 plant and fungal orders to show that plant stress generally becomes lethal when EGSSG/2GSH exceeds −160 mV. We put forward that this change in EGSSG/2GSH is part of the signaling cascade that initiates programmed cell death (PCD), finally causing internucleosomal DNA fragmentation in the final, or execution phase, of PCD. EGSSG/2GSH is therefore a universal marker of plant cell viability and allows us to predict whether a seed will live, germinate, and produce a new plant, or if it will die. 相似文献
75.
Ilse Scroyen Frank Jacobs Leentje Cosemans Bart De Geest Henri R. Lijnen 《Obesity (Silver Spring, Md.)》2010,18(3):638-640
Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play a role in the development of obesity by contributing to adipogenesis, angiogenesis, and extracellular matrix degradation. We have evaluated a potential functional role of TIMP‐1, which inhibits most MMPs, in in vivo adipogenesis. Therefore, human (h) TIMP‐1 was overexpressed by injection in the tail vein of NUDE mice of an adenoviral vector 3 days before injection of 3T3‐F442A preadipocytes in the back. After 4 weeks of high‐fat diet, the de novo formed fat was analyzed. Overexpression of hTIMP‐1 had no effect on de novo formed fat pad mass. However, the blood vessel density of the fat pads from mice overexpressing hTIMP‐1 was significantly lower than in controls (587 ± 11 mm?2 vs. 806 ± 20 mm?2, P < 0.0001) whereas the adipocytes were somewhat larger (1,477 ± 44 µm2 vs. 1,285 ± 32 µm2, P = 0.03). Thus, in vivo hTIMP‐1 overexpression did not significantly affect the extent of de novo adipose tissue formation, but was associated with significantly lower blood vessel density. 相似文献
76.
Aurine Verkest Stephane Bourout Jurgen Debaveye Kristine Reynaert Bernadette Saey Ilse Van den Brande Kathleen D'Halluin 《Plant biotechnology journal》2019,17(7):1236-1247
Targeted Genome Optimization (TGO) using site‐specific nucleases to introduce a DNA double‐strand break (DSB) at a specific target locus has broadened the options available to breeders for generation and combination of multiple traits. The use of targeted DNA cleavage in combination with homologous recombination (HR)‐mediated repair, enabled the precise targeted insertion of additional trait genes (2mepsps, hppd, axmi115) at a pre‐existing transgenic locus in cotton. Here we describe the expression and epigenome analyses of cotton Targeted Sequence Insertion (TSI) events over generations. In a subset of events, we observed variability in the level of transgene (hppd, axmi115) expression between independent but genetically identical TSI events. Transgene expression could also be differential within single events and variable over generations. This expression variability and silencing occurred independently of the transgene sequence and could be attributed to DNA methylation that was further linked to different DNA methylation mechanisms. The trigger(s) of transgene DNA methylation remains elusive but we hypothesize that targeted DSB induction and repair could be a potential trigger for DNA methylation. 相似文献
77.
Houtenbos I Westers TM Stam AG de Gruijl TD Scheper RJ Ossenkoppele GJ van de Loosdrecht AA 《Cancer immunology, immunotherapy : CII》2003,52(7):455-462
PURPOSE: Immunotherapy holds promise as a new strategy for the eradication of residual cells in acute myeloid leukaemia (AML). Leukaemic antigen presenting cells (APCs) combining optimal antigen presentation and tumour antigenicity could be used as potent T cell activators. For clinical purposes it is desirable to culture APCs under serum-free conditions. Therefore, we compared morphological, immunophenotypical and functional outcome of the serum-free culture of AML-APCs to their serum-enriched culture. METHODS: AML blasts (n=19) were cultured in the presence of either a cytokine mix or calcium ionophore (CI) for 14 and 2 days, respectively, in FCS-containing medium (FCS), StemSpan serum-free medium (SP) and CellGro serum-free medium (CG). After culture relative yields were calculated and immunophenotypic analysis of APC markers was performed. The mixed leukocyte reaction (MLR) was used to determine T cell stimulating capacity. RESULTS: Serum-free culture of AML-APCs resulted in comparable morphology, relative yields and immunophenotype to serum-enriched culture. By comparing both serum-free media we observed a trend towards a more mature phenotype of CI-cultured AML-APCs in SP. MLR showed that serum-free cultured cells have equal T cell stimulatory capacity in comparison with serum-enriched culture. CONCLUSION: These data show that the serum-free culture of AML-APCs is feasible and that these APCs are comparable to serum-enriched cultured AML-APCs with regard to morphological, immunophenotypical and functional characteristics. These AML-APCs are suitable for the development of active specific immunisation protocols which meet the criteria for good clinical practise (GCP). 相似文献
78.
Polyhydroxybutyrate (PHB) is a member of a class of thermoelastic polymers called polyhydroxyalkanoates that serve many bacteria as intracellular storage molecules for carbon and energy. Transgenic plants provide a potential means of producing this polymer cost-effectively. To date, however, few reports of the successful production of this polymer have been published, with the exception of work with transgenic Arabidopsis. Using a variety of chimeric constructs, we have determined that the constitutive, chloroplast-localized expression of one of the genes involved in PHB production-the beta-ketothiolase (phbA) gene-is detrimental to the efficient production of transgenic PHB. The alternate use of either inducible or somatically activated promoters allowed the construction of transgenic PHB-producing potato (Solanum tuberosum) and tobacco (Nicotiana tabacum) plants, although the amount of PHB formed was still rather low. Taking advantage of an inducible promoter, the maximal amount of PHB produced in transgenic potato was 0.09 mg g(-1) dry weight. In transgenic tobacco using a somatically activated promoter, up to 3.2 mg g(-1) dry weight was accumulated. In Arabidopsis, the formation of high levels of PHB had previously been shown to be accompanied by severe negative effects on growth and development of the plant. Phasins are proteins known from PHB-producing bacteria speculated to serve as protectants against the highly hydrophobic surface of the PHB granules in the bacterial intracellular milieu. Co-expression of the phasin gene in parallel with the PHB synthesis genes, however, did not lead to reduced symptom development. 相似文献
79.
Ten years after the identification of the gene responsible for fragile X syndrome, recent studies have revealed a list of mRNAs bound by the fragile X gene product and have identified specific sequences required for the interaction between the fragile X protein and its targets. These results are a breakthrough in understanding why absence of the fragile X protein leads to mental retardation. 相似文献
80.
This paper describes the process used to generate lower limb kinematics during single limb stance phase of gait, using musculoskeletal modelling, muscle driven forward simulation and gradient based optimisation techniques (including design of experiment techniques).Initial inputs to the forward simulation process were the normalised quantified muscle activation patterns of 22 muscles, and the initial segmental configuration (both angles and angular velocity) derived from Winter (The biomechanics and motor control of human gait, 1987, University of Waterloo Press, pp. 1-72). Two distinct musculoskeletal models (one including 6 DOF, the other 7 DOF) were defined and a muscle driven forward simulation was implemented.A series of optimisation sequences then were executed to modify the muscle activation patterns and initial segmental configuration, until the system output of the forward simulation approximated the angle data reported by. The accuracy and effectiveness of the analysis sequence proposed and the model response obtained using two distinct musculoskeletal models were verified and analysed with respect to the kinesiology of normal walking. 相似文献