bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assimilate uptake and the regulation of seed development
Authors: Weber Hans , Heim Ute , Golombek Sabine , Borisjuk Ljudmilla , Wobus Ulrich 
Published: September 2008

AbstractSeed development is a series of events involving cell division, followed by cell differentiation and storage activity In legume cotyledons, cell differentiation starts in certain regions and gradually spreads to other parts, thereby building up developmental gradients The entire process appears to be subject to metabolic control The high hexose state of the premature legume embryo as controlled by seed coat-specific invertases favours cell division Differentiation is initiated when hexose decreases and sucrose increases Seed development occurs in a close interaction with seed metabolism and transport processes Movement of photoassimilates from the sieve tubes to the unloading region of the maternal seed tissue is symplasmic and controlled by plasmodesmal passage Sucrose uptake intoVicia fabacotyledons is mediated by a H+-sucrose symporter located in the outer epidermis which generates transfer cells Formation of the sucrose uptake system is induced during the early to mid-cotyledon stage by tissue contact with the maternal seed coat and is controlled by carbohydrate availability In contrast, a hexose transporter gene is also expressed in epidermal cells covering younger, mitotically active regions of the cotyledons The sucrose uptake system apparently generates the high sucrose state immediately preceding the storage phase Sucrose specifically induces storage-associated differentiation processes indicating a specific sucrose-dependent signalling pathway operating in maturing cotyledons Moreover, the mode of sucrose uptake — apoplasmic movement into the epidermal cells with subsequent symplasmic transfer to the storage parenchyma cells — appears to control coordinated cotyledon development Unlike sucrose, amino acid transport into legume cotyledons is passive during early development but at later stages when large amounts of storage proteins are synthesized an additional active uptake system is established to ensure a sufficient supply
Responses of tomato seeds to osmoconditioning as related to temperature and oxygen
Authors: Ozbingol N. , Corbineau F. , Côme D. 
Published: September 2008

AbstractUntreated (control) tomato seeds germinated at temperatures ranging from 15 to 35°C. There was a positive linear relationship between the rate of germination (expressed as the reciprocal of time to obtain 50% germination) and temperature up to the thermal optimum. At higher temperatures, the negative relationship was also linear. The thermal optimum for seed germination was 27–28°C and the lower and maximal temperatures were around 9 and 40°C, respectively. Germination was strongly reduced in atmospheres containing less than 10% oxygen. After pretreatment at 15°C in a polyethylene glycol-8000 solution at –1.0 MPa, seeds germinated faster in a wider range of temperatures, and this stimulatory effect remained after drying back the seeds. Such a pretreatment did not change the optimal and maximal temperatures of germination, but decreased the lower temperature to about 6°C. The beneficial effect of osmoconditioning increased as the duration of the treatment increased and was maximal after 5–7 days. Osmotic pretreatment also reduced the sensitivity of seeds to oxygen deprivation; 50% of the seeds germinated within 7 days in 5% oxygen. The range of temperatures and the concentrations of oxygen which were effective in osmoconditioning were very similar to those which allowed the germination of untreated seeds. In particular, the optimal temperature (27–28°C) and oxygen concentrations (more than 10%) for osmoconditioning and germination were the same. These results confirm that the beneficial effect of osmotic pretreatment (priming) corresponds to the realization of germinationsensu stricto(phase II of the germination process).
Seed development, testa structure and precocious germination of Chinese cabbage (Brassica rapasubsp.pekinensis)
Authors: Ren Chengwei , Bewley J. Derek 
Published: September 2008

AbstractOn the basis of embryo and seed colour, morphology, accumulation of fresh and dry weight, seed development of Chinese cabbage (Brassica rapasubsp.pekinensis) can be divided into 10 discrete but contiguous stages. Precocious germination (PG) occurs in the seeds of a Chinese cabbage mutant on the parent plant mainly during the maturation period (from stage 5 to 8), with either the radicle or the cotyledon protruding out of the testa. All plants of the mutant line produce some PG seeds, but among the seeds, only 18% (maximum) germinate precociously. The developing mutant seeds have higher water contents and lower dry weights than those of the wild-type and are less tolerant of desiccation. The testa structure of Chinese cabbage seed is similar to that of otherBrassicaspecies. In developing seeds, it consists of the epidermis, subepidermis, palisade layer and pigmented layers, while in the mature dry seeds, all the cell layers except the palisade layer are crushed into non-cell structures and are stacked on the outer and inner faces of the palisade layer; the aleurone layer is fused to the testa. An alteration in testa structure of the mutant seeds (both non-germinated and precociously-germinated seeds) is probably related to PG. The secondary cell wall materials are less, or not deposited on the radial and basal walls of the palisade cells on the adaxial side of the testa, which could result in a weaker mechanical restraint, thus leading to PG.
Soybean seed pectinesterase
Authors: Markovič Oskar , Obendorf Ralph L. 
Published: September 2008

AbstractMethanol accumulates in axis tissues of maturing soybean seeds, correlating with preharvest seed deterioration. Accumulation of methanol appears to be associated with the enzymic demethylation of pectin methyl esters by pectinesterase (PE; EC 3.1.1.11). To characterize PE in developing and maturing soybean (Glycine max (L.) Merrill) seeds, enzyme activity was assayed in axis and cotyledon tissues. Activity per g fresh weight was 20–25 times higher in axes than in cotyledons with highest activities between 45 and 60 days after flowering (DAF). Twenty to 33% of the total PE activity was in the ‘soluble’ form (extracted with water, 0.5 M sucrose, 1 M sucrose and water). Soluble and cell-wall-bound PE (subsequently extracted with 1 M NaCI) were purified and characterized from axes of seeds at 45–60 DAF. Purification of PE was achieved through concentration of extracts by ultra-filtration, precipitation with ammonium sulfate (30–80% saturation), dialysis, gel filtration on Sephadex G-75 columns, and ion exchange chromatography on CM Sepharose CL-6B. Further purification of both soluble and bound PE was by isoelectric focusing (IEF) on ultrathin layers of polyacrylamide gel with simultaneous detection of protein and PE activity. It was possible to follow seven bands exhibiting PE activity with pl values between 6.0 and 9.5 in 1 M NaCI-extracts of total homogenates. Differences in the IEF patterns of bound and soluble PE were observed. Whereas the bound enzyme exhibited more basic PE bands (pl 8–9.5), the soluble enzyme had more active bands at pl 6.5, 7.0 and 7.5. The Mr was close to 33 000 and the pH optimum was 7.8 for both soluble and bound PE.
Effects of differential drying rates on viability retention of recalcitrant seeds of Ekebergia capensis
Authors: Pammenter N. W. , Greggains Valerie , Kioko J. I. , Wesley-Smith J. , Berjak Patricia , Finch-Savage W. E. 
Published: September 2008

AbstractThe drying rate of whole seeds of Ekebergia capensis (Meliaceae) was shown to influence the response to desiccation, with rapidly dried seeds surviving to lower water contents. Short-term rapid drying (to water contents higher than those leading to viability loss) actually increased the rate of germination. The form of the time course of decline of axis water content varied with drying rate; slow drying could be described by an exponential function, whereas with rapid drying initial water loss was faster than predicted by an exponential function. These observations suggest that slow drying brought about homogeneous dehydration and that the rapid drying was uneven across the tissue. This raised the possibility that the different responses to dehydration were a function of different distributions of water in the axis tissue under the two drying regimes. However, ultrastructural observations indicated that different deleterious processes may be occurring under the different drying treatments. It was tentatively concluded that a major cause of viability loss in slowly dried material was likely to be a consequence of aqueous-based processes leading to considerable membrane degradation. Uneven distribution of tissue water could not be rejected as a contributory cause of the survival of rapidly dried seeds to low bulk water contents. The differential response to dehydration at different drying rates implies that it is not possible to determine a ‘critical water content’ for viability loss by recalcitrant seeds.
A multifactorial study of conditions influencing longevity of neem (Azadirachta indica) seeds
Authors: Sacandé Moctar , Hoekstra Folkert A. , van Pijlen Jaap G. , Groot Steven P. C. 
Published: September 2008

AbstractThe longevity of neem,Azadirachta indica, seeds from African Sahelian (Burkina Faso) and Asian (Sri Lanka) provenances was studied over two years of storage under different conditions of moisture and temperature. After drying to equilibrium moisture content (MC) at different relative humidities at 20°C, seeds were placed in open storage at 20°C or hermetically sealed in packets at temperatures ranging from −20 to +20°C. There was hardly any difference in storage behaviour between seed batches / lots, whatever their provenance. Seeds originating from mature yellow fruits lived longer than seeds from green or brown fruits. In all storage experiments with seeds having MCs ≥ 10%, viability was preserved best at 10−15°C, indicating that neem seed is chilling (and freezing) sensitive. There was no survival longer than 2 years under these conditions. At MCs of 4–8%, seeds were considerably more tolerant of low temperature storage and had 40–60% viability after 2 years at all temperatures tested (−20 to +20°C). However, the seeds were sensitive to imbibitional stress, which could be alleviated by imbibition at temperatures of 25–30°C or above. The difficult storage behaviour of neem seed seems to stem from: (1) the sensitivity to low temperatures at MCs ≥ 10%; (2) the extreme sensitivity to imbibitional stress after storage at ≤ 8% MC; (3) underestimation of the water activity due to the high oil content of the neem seeds, causing unexpected metabolic stress in the higher MC and temperature range.
Development of soil seed banks beneath synthesized meadow communities after seven years of climate manipulations
Authors: Akinola M. Olatunde , Thompson Ken , Hillier Susan H. 
Published: September 2008

AbstractMeadow microcosms were established from seed on low-fertility soil of known seed bank composition, and subjected to manipulations of simulated grazing, cutting date, temperature and fertility for seven years. The composition and density of the seed bank was then determined in five 2-cm soil layers (0–2, 2–4, 4–6, 6–8 and 8–10 cm). The seed bank contained three distinct groups of species: species present in the original soil, sown species, and ‘others’. The seed bank was little affected by the experimental treatments, presumably because the sown species made only a small contribution to the seed bank. Nearly all the species in the original soil are known to possess persistent seed banks and had survived, although at reduced density, for seven years. Density of the most abundant species in this group, Sagina procumbens, had changed very little over seven years, confirming the well-documented longevity of the seeds of this species. Seeds of sown species made up only about a quarter of the seed bank, despite accounting for virtually all the above-ground vegetation. Of the sown meadow species, only Plantago lanceolata and Alopecurus pratensis were relatively abundant in the seed bank. These results strongly support the conclusion of other authors that most meadow species, once lost owing to the effects of fertilizers or inappropriate management, will not reestablish from the seed bank. Among species which were neither sown nor present in the original soil, the majority possessed adaptations for wind dispersal and had presumably dispersed into the experimental plots from outside. The most abundant member of this group, Betula pendula, had dispersed from a nearby tree. Density of Betula seeds declined sharply with depth, consistent with the view that seeds on the soil surface are rapidly lost, mainly through germination, but seeds that become buried survive much better. Seeds of Betula appear to be persistent but not particularly long-lived.
Post-dispersal seed predation and seed bank persistence
Authors: Hulme P. E. 
Published: September 2008

AbstractThis study examines whether post-dispersal seed predators could be an important selective force in determining the seed bank strategies of grassland plants. It tests the hypothesis that species with persistent seed banks should sustain proportionally less predation of buried seeds than species which have transient seed banks and that this should be true irrespective of seed size. Results are drawn from a field experiment examining the relative susceptibility of surface versus buried seeds for 19 herbaceous taxa exhibiting different degrees of seed bank persistence. The data were consistent with the hypothesis that seed predators (rodents) influence the seed bank characteristics of seeds. Rodents removed proportionally more large seeds than small seeds and removed a smaller proportion of seeds with persistent rather than transient seed banks, independently of seed size. On average, burial reduced seed removal by almost 50%. The decrease in rates of seed removal following burial was marked for seeds with persistent seed banks but negligible for seeds with transient seed banks. Herbaceous plants with relatively large seeds (seed mass > 1 mg) that form persistent seed banks were either completely avoided or only consumed in small quantities by rodents. In contrast, large-seeded species with transient seed banks suffer high rates of seed predation. Models of life-history evolution predict trade-offs between seed dormancy and seed mass since dormancy and seed size are correlated traits that both reduce risk in variable environments and thus will show patterns of negative covariation. This paper presents an alternative explanation for this trade-off based on experimental evidence of a negative relationship between seed bank persistence and predation risk.
Stuff and Nonsense in the Treatment of Older People: Essential Reading for the Over-45s
Authors: James Ian Andrew 
Published: September 2008

AbstractThere is a lot of nonsense talked about how to adapt therapy for older people. This is because often authors fail to define the types of populations they are tailoring their therapy for. Such definitions are important with such a diverse patient group, some of whom were “in-service” during the first world war, while others were “doing drugs and dropping out” in the 1960s. To guide our thinking regarding specific adaptations, this paper presents a framework for clarifying therapeutic need. The second section of the paper illustrates ways in which working psychotherapeutically with older patients has helped inform mainstream CBT theory and practice, with particular reference to competence and schema work.
Cognitive Behavioural Therapy for Mood Disorders
Authors: Meyer Thomas D. , Scott Jan 
Published: September 2008

AbstractThis paper provides a selected review of recent studies highlighting key aspects of mood disorders research. Cognitive models and clinical trials of cognitive therapy of depression are evolving and adapting to increase applicability to the spectrum of depressive symptoms and syndromes experienced by clients, as well exploring beyond acute phase treatment to relapse prevention. In contrast, cognitive models of bipolar disorders and the effectiveness of the therapy are unclear and there are more questions than answers for researchers in this area.
Investment, uncertainty, and production games
Authors: FLÅM S. D. , ERMOLIEV Y. M. 
Published: September 2008

ABSTRACTThis paper explores a few cooperative aspects of investments in uncertain, real options. By hypothesis some production commitments, factors, or quotas are transferable. Cases in point include energy supply, emission of pollutants, and harvest of renewable resources. Of particular interest are technologies or projects that provide anti-correlated returns. Any such project stabilizes the aggregate proceeds. Therefore, given widespread risk aversion, a project of this sort merits a bonus. The setting is formalized as a two-stage, stochastic, production game. Absent economies of scale, such games are quite tractable in analysis, computation, and realization. A core imputation comes in terms of shadow prices that equilibrate competitive, endogenous markets. Such prices emerge as optimal dual solutions to coordinated production programs, featuring pooled commitments, or resources. Alternatively, the prices could result from repeated exchange.
Functional modules integrating essential cellular functions are predictive of the response of leukaemia cells to DNA damage
Authors: Sameith Katrin , Antczak Philipp , Marston Elliot , Turan Nil , Maier Dieter , Stankovic Tanja , Falciani Francesco 
Published: September 2008

Abstract
Motivation: Childhood B-precursor lymphoblastic leukaemia (ALL) is the most common paediatric malignancy. Despite the fact that 80% of ALL patients respond to anti-cancer drugs, the patho-physiology of this disease is still not fully understood. mRNA expression-profiling studies that have been performed have not yet provided novel insights into the mechanisms behind cellular response to DNA damage. More powerful data analysis techniques may be required for identifying novel functional pathways involved in the cellular responses to DNA damage.
Results: In order to explore the possibility that unforeseen biological processes may be involved in the response to DNA damage, we have developed and applied a novel procedure for the identification of functional modules in ALL cells. We have discovered that the overall activity of functional modules integrating protein degradation and mRNA processing is predictive of response to DNA damage.
Availability: Supplementary material including R code, additional results, experimental datasets, as well as a detailed description of the methodology are available at http://www.bip.bham.ac.uk/vivo/fumo.html.
Contact: f.falciani@bham.ac.uk
Supplementary information: Supplementary data are available at Bioinformatics online.
p27Kip1 is overexpressed in very early stages of hepatocarcinogenesis
Authors: Yachida Shinichi , Sakamoto Michiie , Imaida Katsumi , Yokohira Masanao , Saoo Kousuke , Okano Keiichi , Wakabayashi Hisao , Maeta Hajime , Suzuki Yasuyuki 
Published: September 2008

Hepatocellular carcinoma (HCC) associated with chronic liver disease evolves from precancerous lesions and early HCC to more malignant forms. Despite the demonstrated importance of cell‐cycle regulators in tumor biology, there have been few studies of their role in multistep hepatocarcinogenesis. Expression of p27Kip1 and a degradation pathway associated protein, S‐phase kinase‐interacting protein 2 (Skp2), was therefore evaluated in surgically resected specimens of eight adenomatous hyperplasias, 16 early HCC and 126 classical HCC. Immunohistochemistry revealed no p27Kip1 expression in the majority of hepatocytes from normal and cirrhotic liver, whereas positive staining for p27Kip1 protein was found in 75.0% and 93.8% of adenomatous hyperplasias and early HCC, respectively. The average p27Kip1 labeling indices (LI) for adenomatous hyperplasias, early HCC, well differentiated HCC, moderately differentiated HCC and poorly differentiated HCC were 36.99, 43.59, 47.73, 49.24, and 30.21, respectively. Real‐time quantitative reverse transcription–polymerase chain reaction (RT‐PCR) analyses confirmed the increases. Skp2 LI were also significantly elevated in accordance with stepwise progression of hepatocarcinogenesis. Increased expression of Skp2 mRNA was observed most frequently in less differentiated tumors and Kaplan–Meier survival analysis showed a significantly association with a poor prognosis (P = 0.0496). In conclusion, a high level of p27Kip1 expression is evident from early stages of hepatocarcinogenesis, indicating that this parameter could be a useful diagnostic marker for precancerous lesions and early HCC. In addition, Skp2 expression correlates with tumor dedifferentiation and may contribute to biological aggression in HCC. (Cancer Sci 2008; 99: 2152–2159)
Metformin suppresses intestinal polyp growth in ApcMin/+ mice
Authors: Tomimoto Ayako , Endo Hiroki , Sugiyama Michiko , Fujisawa Toshio , Hosono Kunihiro , Takahashi Hirokazu , Nakajima Noriko , Nagashima Yoji , Wada Koichiro , Nakagama Hitoshi , Nakajima Atsushi 
Published: September 2008

Metformin is a biguanide derivative that is widely used in the treatment of diabetes mellitus. One of the pharmacological targets of metformin is adenosine monophosphate‐activated protein kinase (AMPK). We investigated the effect of metformin on the suppression of intestinal polyp formation in ApcMin/+ mice. Administration of metformin (250 mg/kg) did not reduce the total number of intestinal polyp formations, but significantly reduced the number of intestinal polyp formations larger than 2 mm in diameter in ApcMin/+ mice. To examine the indirect effect of metformin, the index of insulin resistance and serum lipid levels in ApcMin/+ mice were assessed. These factors were not significantly attenuated by the treatment with metformin, indicating that the suppression of polyp growth is not due to the indirect drug action. The levels of tumor cell proliferation as determined by 5‐bromodeoxyuridine and proliferating cell nuclear antigen immunohistochemical staining, and apoptosis, via transferase deoxytidyl uridine end labeling staining, in the polyps of metformin‐treated mice were not significantly different in comparison to those of control mice. Gene expression of cyclin D1 and c‐myc in intestinal polyps were also not significantly different between those two groups. In contrast, metformin activated AMPK in the intestinal polyps, resulting in the inhibition of the activation of mammalian target of rapamycin, which play important roles in the protein synthesis machinery. Metformin suppressed the polyp growth in ApcMin/+ mice, suggesting that it may be a novel candidate as a chemopreventive agent for colorectal cancer. (Cancer Sci 2008; 99: 2136–2141)