bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crown rust affects plant performance and interference ability of Italian ryegrass in the post‐epidemic generation
Authors: Mattner S. W. , Parbery D. G. 
Published: November 2007

SummaryThis study investigated the effects of crown rust (caused by Puccinia coronata f.sp. lolii) in Italian ryegrass (Lolium multiflorum) on plant growth and interference ability in the post‐epidemic generation. Rust‐infected Italian ryegrass plants produced seeds with lower weights than healthy plants (on average proportionately 0·36 lower). Furthermore, the early seedling vigour of plants from rust‐infected parents was reduced by 0·50 compared with seed from healthy parents. Under disease‐free conditions in the post‐epidemic generation, mature plants from rust‐infected parents produced 0·13 less shoot dry weight, 0·15 fewer tillers, 0·11 fewer leaves and 0·25 less leaf area than plants from healthy parents. As such, the effects of crown rust in Italian ryegrass persisted for at least one post‐epidemic generation. Under rust‐infected conditions in the post‐epidemic generation, however, the difference in performance between plants from healthy and rust‐infected parents was minimal. This suggests that any advantage plants gain from having healthy parents, compared with rust‐infected parents, might be lost when the post‐epidemic generation is grown under conditions of rust infection. Irrespective of rust infection in the post‐epidemic generation, the magnitude of intra‐specific interference was greater in monocultures of Italian ryegrass from healthy parents than in those from rust‐infected parents. However, the magnitude of inter‐specific interference and the relative interference ability of plants of rust‐infected and healthy parents did not differ. The implications of these results to plant ecology are discussed.
Effects of residual dry matter on net primary production and plant functional groups in Californian annual grasslands
Authors: Bartolome J. W. , Jackson R. D. , Betts A. D. K. , Connor J. M. , Nader G. A. , Tate K. W. 
Published: November 2007

AbstractA five‐year experiment tested the response of above‐ground net primary production (ANPP) and plant functional groups to manipulations in residual dry matter (RDM), reflecting typical grazing practices in Californian annual grasslands. The RDM treatments were 225, 560, 900 and 5000 kg ha−1 with the latter treatment representing no grazing by livestock. ANPP in autumn, winter and spring showed a strong year × RDM interaction indicating that, in periods with higher herbage mass, the highest RDM treatment, representative of no grazing, was usually more productive. However, the opposite pattern was observed for the autumn period when ANPP was lowest. Random effects models indicated that at most 0·20 of the variation in ANPP for any of the three seasons stemmed from RDM treatments, with the remaining variation partitioned among temporal and spatial dimensions or not explained. Cover of grass species was highest under the highest RDM treatment in four of the five years, and lowest for the lowest RDM treatment compared with the two intermediate RDM treatments in the two years with the highest herbage masses. Cover of forbs and clover was higher on the lowest RDM treatment and lower on the highest RDM treatment than on the intermediate treatments. The results suggest that residual RDM values above 550 kg RDM ha−1 are appropriate for annual grasslands with a mean annual precipitation of more than 400 mm and offer a compromise between herbage use and promotion of future productivity and diversity, but direct control of ANPP and composition via management is not attainable because the environmental factors are predominant.
Mixing whole‐crop pea–oat silage and grass–clover silage: positive effects on intake and milk production of dairy cows
Authors: Rondahl T. , Bertilsson J. , Martinsson K. 
Published: November 2007

AbstractForty‐eight high‐yielding dairy cows of the Swedish Red breed were used to examine the effects of providing pea–oat silage (P), grass–clover silage (G) and a 0·50:0·50 mixture of the silages (M) ad libitum in diets with two concentrate levels (7 or 10 kg d−1). A 9‐week experiment, including a 2‐week pre‐experimental period in which the cows were all fed the same diet, and an in vivo apparent digestibility study were conducted comparing the six dietary treatments (M7, M10, P7, P10, G7, G10). Intake and digestibility of the diets and milk production and live weight of the cows were measured. The G silage [11·3 MJ ME kg−1 dry matter (DM)] was first‐cut grass herbage wilted for 24 h prior to addition of an additive, containing formic acid, propionic acid and ammonia, at 4 L t−1 fresh matter (FM). The P forage was cut when the peas were at pod fill and ensiled directly with 6 L t−1 FM of the same additive. The main hypothesis tested, that cows fed the M silage would produce more milk than the cows fed either the P or the G silages, was confirmed. The cows fed the M7 dietary treatment had similar milk yield and milk composition to cows offered the M10, G10 and P10 dietary treatments, and cows offered the G7 and P7 dietary treatments had lower milk and milk protein yields. This suggested that a mixed ration of pea–oat bi‐crop and grass–clover silage has a concentrate‐sparing effect, and that the use of pea–oat bi‐crop and grass–clover silage as a mixed ration for high‐yielding dairy cows can be recommended.
Patterns of leaf and root regrowth, and allocation of water‐soluble carbohydrate reserves following defoliation of plants of prairie grass (Bromus willdenowii Kunth.)
Authors: Turner L. R. , Donaghy D. J. , Lane P. A. , Rawnsley R. P. 
Published: November 2007

AbstractThis study utilized leaf stage‐based defoliation intervals to describe the concentrations and contents of water‐soluble carbohydrate (WSC) and nitrogen (N) in stubble and root reserves and their effect on the regrowth of prairie grass (Bromus willdenowii Kunth.) plants. The priority sequence for allocation of WSC reserves during the regrowth period was also investigated. There were substantially higher concentrations of WSC and N in the stubble compared with the roots following defoliation, confirming the stubble as the primary site for energy storage, with roots playing a lesser role. However, high R2 values for the relationships between WSC concentration in roots and regrowth variables suggested that plants of prairie grass were reliant on WSC reserves from the roots in addition to the stubble to meet the energy requirements of plants until adequate photosynthetic tissue had been produced. The sequence of priority for allocation of WSC reserves followed the order of leaf growth, root growth and tillering during the regrowth period. Although WSC reserves were identified as the primary contributor to plant regrowth following defoliation, there was also a strong relationship between stubble N concentration and regrowth variables.
Comparison of metastatic brain tumour models using three different methods: the morphological role of the pia mater
Authors: Saito Norihiko , Hatori Tsutomu , Murata Nozomu , Zhang Ze‐An , Nonaka Hiroko , Aoki Kazuya , Iwabuchi Satoshi , Ueda Morikazu 
Published: November 2007

SummaryAs methods of cancer diagnosis and treatment progress, interest in metastatic brain tumours continues to increase. There are many studies using various methods of animal model and we considered that each model reflects different pathological processes because of the unique composition of the brain. We prepared metastatic brain tumour models using three different methods. In this study, we attempted to elucidate the roles of the pia mater in brain metastasis. The metastatic foci showed an angiocentric pattern, forming collars of neoplastic cells, and were designated ‘perivascular proliferations’. Furthermore, we observed neoplastic cells that infiltrated the brain parenchyma, the border of which had become indistinct. These were labelled ‘invasive proliferations’. The internal carotid artery injection model reflects haematogenous metastasis. In this model, both perivascular and invasive proliferations were observed. The intrathecal injection model reflects leptomeningeal carcinomatosis. In this model, metastasis to the meninges was observed. In the stereotactic injection model, the tumour proliferation at the injection site and the infiltration into the brain parenchyma were observed. The pia‐glial membrane serves as a scaffold when neoplastic cells spread to the perivascular space forming angiocentric pattern. The pia‐glial membrane is found between the brain parenchyma and blood vessels. Blood vessels penetrate the brain through tunnels known as perivascular spaces that are covered by pia mater. Three different methods which we prepared reflect three different pathological processes. Our findings suggest that the pia mater is a critical factor in brain metastasis.
Cell‐specific SpoIIIE assembly and DNA translocation polarity are dictated by chromosome orientation
Authors: Becker Eric C. , Pogliano Kit 
Published: November 2007

SummarySpoIIIE and FtsK are related proteins that translocate chromosomes across septa. Previous results suggested that SpoIIIE exports DNA and that translocation polarity is governed by the cell‐specific regulation of its assembly, but that FtsK is a reversible motor for which translocation polarity is governed by its DNA substrate. Seeking to reconcile these conclusions, we used cell‐specific GFP tagging to demonstrate that SpoIIIE assembles a complex only in the mother cell, from which DNA is exported, but that DNA translocation‐defective SpoIIIE proteins assemble in both cells. Altering chromosome architecture by soj‐spo0J and racA soj‐spo0J mutations allowed wild‐type SpoIIIE to assemble in the forespore and export the forespore chromosome. Combining LacI‐CFP tagging of oriC with time‐lapse microscopy, we demonstrate that the chromosome is exported from the forespore when oriC fails to be trapped in the forespore. Thus, the position of oriC after septation determines which cell will receive the chromosome and which will assemble SpoIIIE.
RbrA, a cyanobacterial rubrerythrin, functions as a FNR‐dependent peroxidase in heterocysts in protection of nitrogenase from damage by hydrogen peroxide in Anabaena sp. PCC 7120
Authors: Zhao Weixing , Ye Zi , Zhao Jindong 
Published: November 2007

SummaryThe heterocyst is a specialized cell for nitrogen fixation in some filamentous cyanobacteria. Here we report that a rubrerythrin (RbrA) from Anabaena sp. PCC 7120 functions as a peroxidase in heterocysts and plays an important role in protection of nitrogenase. The electron donor for RbrA in H2O2 reduction is NADPH and the electron transfer from NADPH to RbrA depends on ferredoxin:NADP+ oxidoreductase. A rbrA mutant (r27) grew much more slowly than the wild type under diazotrophic conditions. Its nitrogenase activity measured in air was only 8% of that measured under anoxic conditions. Staining r27 filaments with 2′,7′‐dichlorodihydrofluorescein diacetate indicated that heterocysts had a higher H2O2 concentration than the vegetative cells. The expression of rbrA was controlled by two promoters and the promoter for the smaller transcript was regulated by HetR. Spatial expression of rbrA was studied and the results showed that the transcription is localized predominantly in heterocysts. In a mutant lacking nifH and rbrA, the H2O2 concentration in heterocysts was lower than that in the vegetative cells, suggesting that NifH is involved in H2O2 generation. Our results demonstrate that RbrA is a critical enzyme for H2O2 decomposition and provide evidence that nitrogenase autoprotection is important in heterocysts.
The SUN41 and SUN42 genes are essential for cell separation in Candida albicans
Authors: Firon Arnaud , Aubert Sylvie , Iraqui Ismaïl , Guadagnini Stéphanie , Goyard Sophie , Prévost Marie‐Christine , Janbon Guilhem , D'Enfert Christophe 
Published: November 2007

SummaryCompletion of the yeast cell cycle involves extensive remodelling of the cell wall upon separation of mother and daughter cells. We have studied two members of the ascomycete‐specific SUN gene family in Candida albicans. Inactivation of SUN41 yields defects in cell separation and hyphal elongation while inactivation of SUN42 results in minor phenotypic alterations. Simultaneous inactivation of SUN41 and SUN42 is synthetically lethal due to lysis of mother cells after septation. Electronic microscopy reveals cell wall defects mainly localized in the region surrounding the septa. This phenotype is osmoremediable and the conditional double mutants show increased sensitivity to cell wall or cell membrane perturbing agents. The essential function shared by Sun41p and Sun42p is conserved among yeasts because UTH1, a Saccharomyces cerevisiae SUN gene, suppresses the lethality of SUN41 and SUN42 conditional mutants. Investigation of functional genomic data obtained in S. cerevisiae reveals links between members of the SUN gene family and the RAM pathway regulating cell wall‐degrading enzymes specifically involved during cell separation. Thus, the main function of ascomycetous Sun proteins appears linked to cell wall remodelling, with a probable role in counter‐balancing cell wall degradation to avoid cell lysis upon cell separation.
Genetic analysis of the physiological responses to low boron stress in Arabidopsis thaliana
Authors: ZENG CHANGYING , HAN YANLAI , SHI LEI , PENG LISHUN , WANG YUNHUA , XU FANGSEN , MENG JINLING 
Published: November 2007

ABSTRACTBoron (B) is an essential micronutrient for higher plants. There is wide genetic variation in the response to B deficiency among plant species and cultivars. The objective of this study was to identify quantitative trait loci (QTL) that control B efficiency in natural Arabidopsis accessions. The B efficiency coefficient (BEC) and seed yield under low B conditions (SYLB) were investigated by solution culture in two separate experiments in an Arabidopsis recombinant inbred line (RIL) population. Both of the traits studied exhibited high transgressive variation in the RIL population, and, in total, five and three QTL were identified for BEC and SYLB, respectively. Three of the five QTL, including the QTL, AtBE1‐2, that has a large effect on the BEC, were found at the interval of the corresponding QTL for SYLB in both experiments. The close genetic relationship between BEC and SYLB was further confirmed by conditional QTL mapping in the RIL population and unconditional QTL mapping in an AtBE1‐2‐segregated F2 population. Epistatic interactions for the tested traits were analysed, and were found to be widespread in the detected QTL of Arabidopsis in the RIL population. Comparison of the QTL interval for B efficiency with reported B‐related genes showed that 10 B‐related genes, together with one BOR1 homolog (BOR5, At1g74810) were located in the QTL region of AtBE1‐2. These results suggest that natural variation in B efficiency in Arabidopsis has a complex molecular basis. They also provide a basis for fine mapping and cloning of the B‐efficiency genes, with the ultimate aim of discovering the physiological mechanism of action of the genes.
Interaction of heavy metals with the sulphur metabolism in angiosperms from an ecological point of view
Authors: ERNST WILFRIED H. O. , KRAUSS GERD‐JOACHIM , VERKLEIJ JOS A. C. , WESENBERG DIRK 
Published: November 2007

ABSTRACTThe metabolism of sulphur in angiosperms is reviewed under the aspect of exposure to ecologically relevant concentrations of sulphur, heavy metals and metalloids. Because of the inconsistent use of the term ‘metal tolerance’, in this review the degree of tolerance to arsenic and heavy metals is divided into three categories: hypotolerance, basal tolerance and hypertolerance.The composition of nutrient solutions applied to physiological experiments let see that the well‐known interactions of calcium, sulphate and zinc supply with uptake of heavy metals, especially cadmium are insufficiently considered. Expression of genes involved in reductive sulphate assimilation pathway and enzyme activities are stimulated by cadmium and partially by copper, but nearly not by other heavy metals. The synthesis of the sulphur‐rich compounds glucosinolates, metallothioneins and phytochelatins is affected in a metal‐specific way. Phytochelatin levels are low in all metal(loid)‐hypertolerant plant species growing in the natural environment on metal(loid)‐enriched soils.If laboratory experiments mimic the natural environments, especially high Zn/Cd ratios and good sulphur supply, and chemical analyses are extended to more mineral elements than the single metal(loid) under investigation, a better understanding of the impact of metal(loid)s on the sulphur metabolism can be achieved.
Variation in pollen production and pollen viability in natural populations of gynodioecious Beta vulgaris ssp. maritima: evidence for a cost of restoration of male function?
Authors: DUFAŸ M. , VAUDEY V. , DE CAUWER I. , TOUZET P. , CUGUEN J. , ARNAUD J.‐F. 
Published: November 2007

AbstractGynodioecious species are defined by the co‐occurrence of two clearly separated categories of plants: females and hermaphrodites. The hermaphroditic category may, however, not be homogeneous, as male fitness may vary among hermaphrodites as a result of many biological factors. In this study, we analysed estimates of pollen quantity and viability in the gynodioecious Beta vulgaris ssp. maritima, comparing hermaphrodites bearing a male‐fertile cytotype and hermaphrodites bearing cytoplasmic male sterility (CMS) genes, which are counteracted by nuclear restoration factors. We show that: (i) pollen quantity continuously varies among restored hermaphrodites, suggesting a complex genetic determination of nuclear restoration; (ii) pollen viability was lower in restored (CMS) hermaphrodites than in non‐CMS hermaphrodites, probably because of incomplete restoration in some of these plants; and (iii) pollen quantity and viability also varied among hermaphrodites with male‐fertile cytotypes, possibly a result of a silent cost of restoration. Finally, we discuss the consequences of these results for pollen flow and the dynamics of gynodioecy.
The comparison of the diuretic and natriuretic efficacy of continuous and bolus intravenous furosemide in patients with chronic kidney disease
Authors: SANJAY SRINIVAS , ANNIGERI RAJEEV A , SESHADRI RAJAGOPALAN , RAO BUDITHI SUBBA , PRAKASH KOWDLE C , MANI MUTHU KRISHNA 
Published: November 2007

SUMMARY:Aim: To compare natriuretic, kaliuretic, diuretic and free water clearance efficacy of continuousversusbolus intravenous furosemide administration in patients with chronic renal insufficiency.Material and methods: In a prospective randomized cross‐over trial, 42 patients of chronic renal insufficiency were randomized to receive the same dose of intravenous furosemide as bolus and continuous infusion. The effects of bolus and intravenous administration of furosemide on the volume of urine, sodium and potassium excretion were assessed.Results: Mean age was 53.6 ± 14 years and 23 (55%) were male. The mean modification of diet in renal disease glomerular filtration rate was 20.5 ± 17 mL/min per 1.73 m2. The urinary excretion of sodium in intravenous bolus and infusion was 98.1 ± 78 and 114.4 ± 100 mmol, respectively (P = 0.001). Total urinary volume following bolus and infusion of furosemide was 1064 ± 627 and 1170 ± 764 mL, respectively (0.001). The excretion of potassium was similar in bolus (15.8 ± 16.6) and infusion (14.3 ± 9) administration (P = 0.11). The fractional excretion of sodium was higher following infusion (16.63 ± 16.1) than bolus administration (12.87 ± 9) of furosemide (P = 0.016).Conclusion: Continuous intravenous infusion of furosemide has significantly better natriuretic and diuretic effect than bolus administration of the same dose of the drug in patients with advanced chronic renal insufficiency.
4‐Methylumbelliferone inhibits hyaluronate synthesis in human uterine cervical fibroblasts
Authors: Tanaka Kanji , Taniguchi Ryousuke , Higuchi Tsuyoshi , Ozaki Takashi , Mizunuma Hideki , Takagaki Keiichi 
Published: November 2007

AbstractAim:  Hyaluronate plays an important role in the regulation of cervical function during parturition. In our previous study we showed that 4‐methylumbelliferone (MU) suppresses hyaluronate synthesis by cultured human skin fibroblasts. The present study investigated the effects of MU on fibroblasts obtained from the human uterine cervix and assessed the possibility of controlling cervical ripening with MU.Methods:  Human uterine cervical fibroblasts were collected from uterine cervices obtained from the uteri of three patients who had a total hysterectomy for uterine myoma at Hirosaki University Hospital. The fibroblasts were cultured in Dulbecco's modified Eagle's medium until confluence. They were then cultured in medium containing [3H]glucosamine (0.074 MBq/mL) with various MU doses. Hyaluronate synthesis was evaluated by assessing the incorporation of [3H]glucosamine into the soluble fraction of hyaluronate. Three independent studies were carried out on each specimen to clarify whether MU causes compositional changes or promotes hyaluronate degradation, whether the inhibitory effects of MU on hyaluronate synthesis are dose‐dependent, and whether the effects of MU are reversible.Results:  MU added to the medium of the cultured cells reduced the synthesis of hyaluronate in a dose‐dependent manner. After MU was removed from the medium, hyaluronate synthesis recommenced, and the amount of [3H]hyaluronate synthesized was similar to the control level.Conclusions:  MU inhibits the synthesis of hyaluronate in human uterine cervical fibroblasts.
Treatment options for bacterial vaginosis in patients at high risk of preterm labor and premature rupture of membranes
Authors: Darwish Atef , Elnshar Ehab M. , Hamadeh Suha M. , Makarem Mohammad H. 
Published: November 2007

AbstractAim:  To estimate the efficacy of different therapeutic modalities on proven cases of bacterial vaginosis (BV) in patients at high risk of preterm labor and premature rupture of membranes.Methods:  This was a longitudinal prospective comparative study set in the antenatal outpatient clinic of the department of Obstetrics and Gynecology, Faculty of Medicine, Assiut University, Assiut, Egypt. Four hundred and sixty‐eight patients with a clinical picture of threatened preterm labor or at high risk of premature rupture of membranes in the third trimester were screened for BV. Positive BV was diagnosed in 156 patients. They were randomly classified into four equal groups according to the line of medical treatment. The treatments were: (i) oral metronidazole, (ii) clindamycin vaginal cream, (iii) oral clindamycin, or (iv) metronidazole vaginal suppositories. The effects of medical treatment on Amsel's criteria as well as maternal and fetal outcomes were measured.Results:  Based on Amsel's criteria, 156 patients (33.3%) were diagnosed with BV. There was a significant disappearance of vaginal discharge, with decreased percentages of pH > 4.5, positive amine test, and clue cells after treatment of BV in the four groups without any statistically significant difference between them. There were variable effects of the different treatments on increasing birthweight values, admission to neonatal intensive care units, and prolongation of the gestational age. Some maternal adverse effects have been recorded. There were significant improvements of the outcomes for oral metronidazole and clindamycin compared with outcomes for intravaginal metronidazole and clindamycin.Conclusions:  Metronidazole and clindamycin achieve nearly equivalent cure rates when administered orally or vaginally in patients at high risk of preterm labor and premature rupture of membranes. Oral metronidazole is considered the drug of choice in treating BV due its high cure rate, better outcomes, and low cost.