234 research outputs found

    Some consequences of the A/A-bar distinction of scrambling

    Get PDF
    It has been discussed that clause intermal scrambling (CIS) involves A or A-bar movement whereas long distance scrambling (LDS) involves A-bar movement (cf. Mahajan (1989), Webelhuth (1989), Saito (1992)). ..

    Defoliating to 12-15 leaves increases calcium concentration and decreases blossom-end rot incidence in fruit of tomato plant grown under moderate water stress

    Get PDF
    The objectives of this study were to (i) determine the optimum number of whole leaves to retain on a tomato plant for effective blossom-end rot (BER) management and (ii) explore the relationship between shoot calcium (Ca) and fruit Ca in non-defoliated plants in two different sized fruit cultivars, a large-fruited cultivar ‘Momotaro fight’ and a medium-fruited cultivar ‘Cindy sweet’. Treatments involved maintaining 18, 15 and 12 leaves on a plant. All lateral shoots were removed regularly throughout the growing period except the shoot closest to the flowering truss in the 18-leaf treatment. At the length of 10cm, these shoots were sampled for real time Ca determination using a hand held Ca2+ meter. In the plants defoliated to 18 leaves, BER was higher in ‘Momotaro fight’ at 10% compared to 2% in ‘Cindy sweet’. Fruit growth rate was significantly increased by defoliation in ‘Momotaro fight’, however no significant difference was observed among treatments in ‘Cindy sweet’. Defoliating to 12 leaves increased daily Ca transport rate by 59% and 37% in ‘Momotaro fight’ and ‘Cindy sweet’, respectively. Defoliating to 12 leaves increased the water-soluble Ca concentration in the distal part of fruit by 34% and 14% in ‘Momotaro fight’ and ‘Cindy sweet’, respectively. In the plants defoliated to 18 leaves where only old yellowish leaves were removed, a significant steady decrease was observed in the concentration of water soluble Ca in the distal part of fruit with increase in truss order. There was a significant linear relationship between water-soluble Ca concentration in the distal part of the fruit and Ca concentration in the lateral shoot of plants defoliated to 18 leaves. We conclude that under moderate water stress by root zone restriction and also certain other BER inductive conditions, defoliation to 12–15 leaves on a tomato plant should be a promising approach for decreasing BER incidence in susceptible large fruit cultivars

    Activation of STAT3 by the Hepatitis C Virus Core Protein Leads to Cellular Transformation

    Get PDF
    The signal transducer and activator of transcription (STAT) family proteins are transcription factors critical in mediating cytokine signaling. Among them, STAT3 is often constitutively phosphorylated and activated in human cancers and in transformed cell lines and is implicated in tumorigenesis. However, cause of the persistent activation of STAT3 in human tumor cells is largely unknown. The hepatitis C virus (HCV) is a major etiological agent of non-A and non-B hepatitis, and chronic infection by HCV is associated with development of liver cirrhosis and hepatocellular carcinoma. HCV core protein is proposed to be responsible for the virus-induced transformation. We now report that HCV core protein directly interacts with and activates STAT3 through phosphorylation of the critical tyrosine residue. Activation of STAT3 by the HCV core in NIH-3T3 cells resulted in rapid proliferation and up-regulation of Bcl-XL and cyclin-D1. Additional expression of STAT3 in HCV core-expressing cells resulted in anchorage-independent growth and tumorigenesis. We propose that the HCV core protein cooperates with STAT3, which leads to cellular transformation

    Increased Rac1 activity and Pak1 overexpression are associated with lymphovascular invasion and lymph node metastasis of upper urinary tract cancer

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Lymphovascular invasion (LVI) and lymph node metastasis are conventional pathological factors associated with an unfavorable prognosis of urothelial carcinoma of the upper urinary tract (UC-UUT), but little is known about the molecular mechanisms underlying LVI and nodal metastasis in this disease. Rac1 small GTPase (Rac1) is essential for tumor metastasis. Activated GTP-bound Rac1 (Rac1 activity) plays a key role in activating downstream effectors known as Pak (21-activated kinase), which are key regulators of cytoskeletal remolding, cell motility, and cell proliferation, and thus have a role in both carcinogenesis and tumor invasion.</p> <p>Methods</p> <p>We analyzed Rac1 activity and Pak1 protein expression in matched sets of tumor tissue, non-tumor tissue, and metastatic lymph node tissue obtained from the surgical specimens of 108 Japanese patients with UC-UUT.</p> <p>Results</p> <p>Rac1 activity and Pak1 protein levels were higher in tumor tissue and metastatic lymph node tissue than in non-tumor tissue (both <it>P </it>< 0.0001). A high level of Rac1 activity and Pak1 protein expression in the primary tumor was related to poor differentiation (<it>P </it>< 0.05), muscle invasion (<it>P </it>< 0.01), LVI (<it>P </it>< 0.0001), and lymph node metastasis (<it>P </it>< 0.0001). Kaplan-Meier survival analysis showed that an increase of Rac1 activity and Pak1 protein was associated with a shorter disease-free survival time (<it>P </it>< 0.01) and shorter overall survival (<it>P </it>< 0.001). Cox proportional hazards analysis revealed that high Rac1 activity, Pak1 protein expression and LVI were independent prognostic factors for shorter overall and disease-free survival times (<it>P </it>< 0.01) on univariate analysis, although only Pak1 and LVI had an influence (<it>P </it>< 0.05) according to multivariate analysis.</p> <p>Conclusions</p> <p>These findings suggest that Rac1 activity and Pak1 are involved in LVI and lymph node metastasis of UC-UUT, and may be prognostic markers for this disease.</p

    トウガラシ(Capsicum baccatum)における カプサイシノイド含量の変異とその非辛味系統

    Get PDF
    The chili pepper (Capsicum) is both an important spice and fresh vegetable worldwide. C. baccatum is a lesser known domesticated species that is native to the Andean region. Fruit traits such as color, shape, and pungency markedly vary in this species. C. baccatum has potential as a bioresource for future chili pepper breeding programs. Although extensive studies have been conducted on the pungency of C. annuum, that of C. baccatum has not been examined in as much detail. In the present study, capsaicinoid contents were analyzed in 36 C. baccatum accessions. Capsaicinoid contents ranged between 0 and 4,258 μg/gDW. Furthermore, a negative relationship was observed between capsaicinoid contents and fruit weights. Although the pungency of C. baccatum is regarded as low-mild, very few non-pungent accessions were detected ; only one non-pungent accession (‘Kaleidoscope’) was identified among the C. baccatum accessions examined. In order to validate the stability of non-pungency in the accession, capsaicinoid contents were determined at different harvest dates, along with other accessions with different pungencies. Although capsaicinoid contents in other C. baccatum accessions changed with the picking date, capsaicinoid was not detected in ‘Kaleidoscope’ at any date. The non-pungent accession reported here may be useful for future C. baccatum pepper breeding programs. トウガラシ(Capsicum 属)は世界的に重要な香辛料および野菜である.C. baccatum は南米原産のマイナーな栽培種であるが,果色,果形や辛味など果実形質に多様性が認められることから,トウガラシ遺伝資源として注目されている.トウガラシの辛味性についてはC. annuum 種において多くの研究が行われているが,C. baccatum 種においては十分研究されていない.  本研究では,C. baccatum 36系統について辛味成分カプサイシノイドの含量を調査した.カプサイシノイド含量の幅は0 ~4,258 ㎍ /gDW であった.また果実重と辛味成分含量の間に負の相関が認められた.C. baccatum の辛味は低〜中程度であるが,非辛味系統はほとんど認められず,唯一1 系統(‘Kaleidoscope’)が非辛味であった.この非辛味の安定性を調査するために,辛味程度の異なる系統とともに異なる収穫時期におけるカプサイシノイド含量を調査した.  他のC. baccatum 系統ではカプサイシノイド含量は収穫時期で変化したが,‘Kaleidoscope’ ではいずれの収穫時期でもカプサイシノイドは検出されなかった.本研究で見出された非辛味系統は将来のC. baccatum の育種において有用であろう

    Fasciation in Strawberry Floral Organs and Possible Implications for Floral Transition

    Get PDF
    Fasciation in strawberry is characterized by an enlarged and flattened receptacle, clustering of flowers, and altered inflorescence architecture. However, the developmental process of fasciated flowers remains obscure. In this study, the fasciation incidence and developmental process in the primary fruit and inflorescence architecture were evaluated and compared for the non-susceptible cultivars, ‘Nyoho’ and ‘Sagahonoka’ and one of the most susceptible cultivars, ‘Ai-Berry’. The severity and frequency of flower and inflorescence fasciation was clearly greater in the vigorously growing large plants of ‘Ai-Berry’ compared to small plants and large plants of the other two cultivars. In ‘Ai-Berry’, the deformation of the large shoot apical meristem (SAM) into an oval shape was the initial symptom observed before and during floral transition. Such oval-shaped SAMs often differentiated two or more leaf primordia almost at the same time, which then developed into divided multiple vegetative SAMs before floral transition and linearly-fasciated SAMs during floral transition, respectively. The development of fasciation symptoms was observed after downregulation of FaTFL1. Although inflorescence or receptacle fasciation could be controlled when early and rapid floral induction was achieved by intermittent low-temperature treatment, severe fasciation was observed in late-flowered plants which were either not responsive or not subjected to this treatment. These results indicate that fasciation of floral organs may be triggered and develop during floral transition and that temperature fluctuations around boundary values between floral inhibition to induction may cause a half-finished or slowly processed floral transition and finally result in severe fasciation in vigorously growing ‘Ai-Berry’ plants

    Comparison of LEDs, Fluorescent Lamps and Incandescent Bulbs for Long-day Treatment of Forcing Strawberries as Affected by Respective Color Temperature

    Get PDF
    Long day (LD) treatment is frequently applied for horticultural crops, including strawberry, and sufficient effect similar to 4 to 6hours of day time elongation in the evening can be achieved by 1 to 3hours of night break in the mid night. Incandescent lamps (IC) have long been an important light source, but the general incandescent lamps are out of production and have been replaced with LED or florescent lamps (FL). Thus, we compared light sources and their color temperature (2,800K, warm white similar to IC; 6,500K, daylight) in different lighting programs. The effectiveness of 3 and 4cycles of alternate intermittent lighting, 30min on/30min off, were equal to and larger than 2hours of night break, respectively. Measured intensity of illumination (lux) at the canopy surface by 2,800K LED (6.9W) and FL (12W) was 1.50 and 0.95times as large as IC (54W), but leaf growth under LED and FL was similar to and less vigorous than IC, respectively. On the other hand, intensity values of illumination by 6,500K LED (6.9W) and FL (12W) were both 1.20times as large as 2,800K ones, but 6,500K light sources were much less effective compared to 2,800K ones. Daylight type LED and FL which have higher luminance efficiency but emit less red light compared to warm white ones, are not suitable as alternative light sources for IC

    Effect of Beginning Date of Intermittent Low Temperature Treatments on Flowering of Tray-grown Strawberry 'Nyoho'

    Get PDF
     Intermittent low temperature storage is expected to be a new artificial flower-inducing treatment and becoming to be a practical procedure as it does not require expensive equipment or much energy cost. Tray-grown ‘Nyoho’ plants were placed in a refrigerator (15°C, in the dark) for 3 days and then transferred to a further outdoor shelter for 3 days. Plants were transferred at noon and this cycle was repeated twice (3D/3D). Such 3D/3D treatments were begun on August 22, 25, 28, 31, and September 3and the effectiveness on flowering was determined for 2 years. Both in 2012 and 2013, treatments begun before August 28 were less effective compared to the treatments begun on August 28 or later. Continuous 6 days of 15°C storage (6D) was effective to some extent, but 6D from August 25 was apparently less effective compared to those begun later. Both in intermittent and continuous treatments for ‘Nyoho’, it was confirmed that any flower-inducing effect became relatively small and unstable when the treatments were begun before 28 August in Okayama

    Effect of seed cold PEG–priming concentration and period followed by re–drying on germination, growth and flowering of Eustoma grandiflorum (Raf.) Shinn ʻExe Lavenderʼ

    Get PDF
    This study aimed to investigate whether seed cold priming by PEG‒6000, followed by re‒drying would affect the germination, growth, and flowering of Eustoma ‘Exe Lavender’ raised seedling under high temperatures. Seeds of control treatment were not treated with cold‒priming or re‒drying. In experiment 1, seeds were cold‒primed with water and PEG‒6000 at ‒0.75 and ‒1.5 MPa for 5 weeks at 10°C in the dark and then subjected to re‒dried and storage for 30 days at 10°C. The results showed that cold‒primed seeds germinated earlier than those of the control. Compared to water treatment, plants grown from PEG‒6000 treatments and re‒drying showed similar germination rate, bolting rate, days to bolting, bolting node and flowering rate. In experiment 2, cold priming periods by water and ‒1.5 MPa PEG‒6000 were investigated for 4, 5, 6, 7, and 8 weeks. ‘Exe Lavender’ seeds treated with cold water and in the dark for longer than 5 weeks increased their percentage of radicle emergence and decreased germination rate after 30 days of re‒drying and storage. Meanwhile, those treated with cold-PEG did not protrude the radicle even for 8 weeks of priming and maintained the germination rate after re‒drying and storage. Days to bolting and days to flowering tended to decrease when the priming period decreased. The results suggest that the seed cold priming treatment by ‒1.5 MPa PEG‒6000 and subsequent re‒drying improved germination rate and maintained bolting rate and flowering rate in Eustoma compared to cold priming treatment by water raised seedling under high temperature conditions
    corecore