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81.
Bone morphogenetic protein 15 and growth differentiation factor 9 co-operate to regulate granulosa cell function in ruminants 总被引:9,自引:0,他引:9
McNatty KP Juengel JL Reader KL Lun S Myllymaa S Lawrence SB Western A Meerasahib MF Mottershead DG Groome NP Ritvos O Laitinen MP 《Reproduction (Cambridge, England)》2005,129(4):481-487
The oocyte-secreted polypeptide growth factors, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15, also known as GDF9B) have both been shown to be essential for ovarian follicular development and ovulation rate. In addition, it is known from both in vivo and in vitro studies that these factors co-operate in some manner. To date, most studies examining the in vitro effects of these growth factors have used the rodent model. However, the evidence suggests that these growth factors have somewhat different roles between rodents and ruminants. Therefore, the objectives of these studies were to examine the effects of GDF9 and BMP15, alone and together, on the functions of ovine and bovine granulosa cells under in vitro conditions. Ovine (o)BMP15 given together with murine (m)GDF9 or oGDF9 was more potent in stimulating (3)H-thymidine incorporation by ovine granulosa cells compared with each growth factor alone. For bovine granulosa cells, there appeared to be little or no co-operativity between oBMP15 and oGDF9 as oBMP15 alone was as potent as any combination of the two growth factors in stimulating (3)H-thymidine uptake. The species of origin of GDF9 affected the progesterone response in ovine granulosa cells with mGDF9 stimulating and oGDF9 inhibiting progesterone production. Ovine BMP15 alone had no effect on progesterone production by ovine granulosa cells and these growth factors did not appear to co-operate. FSH-stimulated progesterone production by bovine granulosa cells was most potently inhibited when oBMP15 and murine or ovine GDF9 were administered together. As was observed for progesterone, the species of origin of GDF9 affected inhibin production by ovine granulosa cells where mGDF9 inhibited while oGDF9 stimulated production. Murine GDF9 also inhibited inhibin production from bovine granulosa cells. For both ovine and bovine granulosa cells, BMP15 alone had no effect on inhibin production and there did not appear to be any co-operation between GDF9 and BMP15. These results indicate that the effects of BMP15 and GDF9 varied with respect to the species of origin of the growth factor. Moreover, the effects of GDF9 and BMP15 together were often co-operative and not always the same as those observed for these growth factors alone. 相似文献
82.
Bone morphogenetic protein 15 and growth differentiation factor 9 co-operate to regulate granulosa cell function 总被引:7,自引:0,他引:7
McNatty KP Juengel JL Reader KL Lun S Myllymaa S Lawrence SB Western A Meerasahib MF Mottershead DG Groome NP Ritvos O Laitinen MP 《Reproduction (Cambridge, England)》2005,129(4):473-480
The oocyte-secreted polypeptide growth factors, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15, also known as GDF9B) have both been shown to be essential for ovarian follicular growth and function. The effects of murine (m) and ovine (o) GDF9 as well as oBMP15, alone or together, on 3H-thymidine uptake and progesterone and inhibin production by granulosa cells from rats were determined. Murine GDF9 stimulated thymidine incorporation by granulosa cells whereas oGDF9 and oBMP15 alone had no effect. However, oBMP15 given together with mGDF9 or oGDF9 was very potent in stimulating 3H-thymidine incorporation by granulosa cells with a greater than 3-fold stimulation compared with any growth factor alone. The synergistic effect of oBMP15 and oGDF9 was almost completely blocked by antibodies generated against these growth factors when administered either alone or in combination. While neither GDF9 (murine or ovine) nor oBMP15 were able to modulate FSH-stimulated progesterone production on their own, FSH-stimulated progesterone production by granulosa cells was potently inhibited when BMP15 and GDF9 were administered together. Immunoreactive alpha-inhibin levels increased more than 15-fold from granulosa cells when BMP15 and GDF9 were given together whereas consistent stimulatory effects of either growth factor alone were not observed. The effects of GDF9 and BMP15, when added together, were different than those observed for the growth factors alone. Therefore, we hypothesize that within the ovary, these oocyte-secreted growth factors co-operate to regulate proliferation and gonadotropin-induced differentiation of granulosa cells in mammals. 相似文献
83.
Eighty-seven grain-finished steers were harvested, evaluated, and fabricated into wholesale cuts to determine what measured composition indicators most accurately describe the percentage of closely trimmed salable meat yield. Indicators of lean and fat composition present at the cross-section between the 12th and 13th ribs were objectively evaluated using Assess image analysis software. Salable meat yield ranged from 50.18% to 72.92%, trimmable fat yield ranged from 12.87% to 36.69%, and bone yield ranged from 10.07% to 19.21%. Regression models were developed to estimate percentage of total salable meat yield. Composition indicators chosen to predict salable meat yield included hot carcass weight (HCW), perinephric fat weight, longissimus muscle area (LMA), subcutaneous fat thickness (SFT), ratio of LMA to subcutaneous fat area, and ratio of subcutaneous fat depth to HCW. These results indicate that prediction of beef carcass salable meat yield can be improved via modification to current measures used in the USDA yield grade equation and addition of new measures. 相似文献
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86.
Conzelmann Annette; Pauli Paul; Mucha Ronald F.; Jacob Christian P.; Gerdes Antje B. M.; Romanos Jasmin; B?hne Christina G.; Heine Monika; Boreatti-Hümmer Andrea; Alpers Georg W.; Fallgatter Andreas J.; Warnke Andreas; Lesch Klaus-Peter; Weyers Peter 《Canadian Metallurgical Quarterly》2010,119(3):594
Adults with attention-deficit/hyperactivity disorder (ADHD) were examined for early and late attentional processes as a function of controlled attention. The test paradigm was the attentional modulation of prepulse inhibition (PPI; early controlled attentional processing) and prepulse facilitation (PPF; late controlled attentional processing). In 49 patients and 49 controls, the authors measured acoustic startle responses to 96-dB startle pulses preceded 120, 240 (for PPI), 2,000, and 4,500 (for PPF) ms by a 68-dB prepulse noise. Geometric figures signaled that prepulses were to be ignored or attended to (automatic vs. controlled attention). ADHD patients exhibited deficits in prepulse modulation, but these reflected an interaction of controlled attention and time of information processing. Normal PPI and PPF occurred under all conditions except for controlled attentional modulation of PPI. Attention deficits in ADHD patients may reflect not general derangements in information processing or ability to attend but, rather, selective disturbances of controlled attention during early information processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Pauli Brattico 《Minds and Machines》2010,20(2):213-241
Humans grasp discrete infinities within several cognitive domains, such as in language, thought, social cognition and tool-making. It is sometimes suggested that any such generative ability is based on a computational system processing hierarchical and recursive mental representations. One view concerning such generativity has been that each of the mind’s modules defining a cognitive domain implements its own recursive computational system. In this paper recent evidence to the contrary is reviewed and it is proposed that there is only one supramodal computational system with recursion in the human mind. A recursion thesis is defined, according to which the hominin cognitive evolution is constituted by a recent punctuated genetic mutation that installed the general, supramodal capacity for recursion into the human nervous system on top of the existing, evolutionarily older cognitive structures, and it is argued on the basis of empirical evidence and theoretical considerations that the recursion thesis constitutes a plausible research program for cognitive science. 相似文献
88.
Dr. Christopher R. M. Asquith Dr. Graham J. Tizzard James M. Bennett Carrow I. Wells Dr. Jonathan M. Elkins Prof. Timothy M. Willson Prof. Antti Poso Dr. Tuomo Laitinen 《ChemMedChem》2020,15(13):1200-1215
Water networks within kinase inhibitor design and more widely within drug discovery are generally poorly understood. The successful targeting of these networks prospectively has great promise for all facets of inhibitor design, including potency and selectivity for the target. Herein, we describe the design and testing of a targeted library of 4-anilinoquin(az)olines for use as inhibitors of cyclin G-associated kinase (GAK). GAK cellular target engagement assays, ATP binding-site modelling and extensive water mapping provide a clear route to access potent inhibitors for GAK and beyond. 相似文献
89.
The Discrete Basis Problem 总被引:2,自引:0,他引:2
Miettinen Pauli Mielik inen Taneli Gionis Aristides Das Gautam Mannila Heikki 《Knowledge and Data Engineering, IEEE Transactions on》2008,20(10):1348-1362
Matrix decomposition methods represent a data matrix as a product of two factor matrices: one containing basis vectors that represent meaningful concepts in the data, and another describing how the observed data can be expressed as combinations of the basis vectors. Decomposition methods have been studied extensively, but many methods return real-valued matrices. Interpreting real-valued factor matrices is hard if the original data is Boolean. In this paper, we describe a matrix decomposition formulation for Boolean data, the Discrete Basis Problem. The problem seeks for a Boolean decomposition of a binary matrix, thus allowing the user to easily interpret the basis vectors. We also describe a variation of the problem, the Discrete Basis Partitioning Problem. We show that both problems are NP-hard. For the Discrete Basis Problem, we give a simple greedy algorithm for solving it; for the Discrete Basis Partitioning Problem we show how it can be solved using existing methods. We present experimental results for the greedy algorithm and compare it against other, well known methods. Our algorithm gives intuitive basis vectors, but its reconstruction error is usually larger than with the real-valued methods. We discuss about the reasons for this behavior. 相似文献
90.
Who does not know the lavender's perfume so characteristic of the Provence? The lavandin presents a better yield in essential oil that is used mainly in perfumes and cosmetics, but also in washing powders and cleaning materials. The chemical and thermal study, made on the same stalk of the lavandin, during the period from January to August, responds to two goals. First for economic appearance, we observed a higher yield of essential oil in open or wilted flowers. The automation of the flowers gathered has induced a decreasing of the essential oil in distillation, on account of the recovery of the branches without oil. Moreover, the water, mineral ashes, cellulose, lignin, holocellulose, and hemicellulose contents are computed in all the aerial parts (new and old leaves, branches). Second, the wild lavender, like other plants of the land of Provence, could be at the start of the forest fire. The inflammability risk can be observed by thermal analysis at about 300°C: presence of an exothermic peak by DTA, weight loss by TG, and determination of the maximum decomposition rate by differential thermogravimetry (DTG). In high‐heating rates (about 50°C/min), the decomposition of the aerial parts of the plant increases mainly with the cellulose level. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1629–1641, 2000 相似文献