bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pre‐oxygenation in pregnancy: the effect of fresh gas flow rates within a circle breathing system*
Authors: Russell E. C. , Wrench I. , Feast M. , Mohammed F. 
Published: June 2008

SummaryWe have investigated the effect of oxygen flow rate on pre‐oxygenation in pregnant patients at term using a circle system. Twenty patients presenting for elective Caesarean section maintained tidal volume breathing through a standard circle system for 3 min. Subjects were pre‐oxygenated using oxygen flow rates of 5 l.min−1, 10 l.min−1 and 15 l.min−1 presented in random order. The mean (SD) fractional end‐tidal oxygen at the end of 3 min was 0.86 (0.07) for 5 l.min−1, 0.92 (0.05) for 10 l.min−1and 0.90 (0.09) for 15 l.min−1 (p < 0.001). Entrainment of air occurred in 22% of pre‐oxygenation sessions. Oxygen flow rates of 10 l.min−1 or above provide optimal pre‐oxygenation using a circle system in term parturients. In our study, entrainment of air occurred in a surprisingly high percentage of cases.
The application of ethephon (an ethylene releaser) increases growth, photosynthesis and nitrogen accumulation in mustard (Brassica juncea L.) under high nitrogen levels
Authors: Khan N. A. , Mir M. R. , Nazar R. , Singh S. 
Published: June 2008

AbstractEthephon (2‐chloroethyl phosphonic acid), an ethylene‐releasing compound, influences growth and photosynthesis of mustard (Brassica juncea L. Czern & Coss.). We show the effect of nitrogen availability on ethylene evolution and how this affects growth, photosynthesis and nitrogen accumulation. Ethylene evolution in the control with low N (100 mg N kg−1 soil) was two‐times higher than with high N (200 mg N kg−1 soil). The application of 100–400 μl·l−1 ethephon post‐flowering, i.e. 60 days after sowing, on plants receiving low or high N further increased ethylene evolution. Leaf area, relative growth rate (RGR), photosynthesis, leaf nitrate reductase (NR) activity and leaf N reached a maximum with application of 200 μl·l−1 ethephon and high N. The results suggest that the application of ethephon influences growth, photosynthesis and N accumulation, depending on the amount of nitrogen in the soil.
QTL analysis of leaf morphological characters in a Quercus robur full‐sib family (Q. robur × Q. robur ssp. slavonica)
Authors: Gailing O. 
Published: June 2008

AbstractThe distinction between white oak species (section Quercus sensu stricto) is largely based on leaf morphological characters. There is, however, considerable within‐species variation and no single species‐diagnostic character, possibly due to phenotypic plasticity and/or underlying genetic variation. The aim of the present study was to identify quantitative trait loci (QTL) underlying the high within‐species variation for leaf morphological characters in an F1 full‐sib family derived from a cross between Q. robur and Q. robur ssp. slavonica. In accordance with an earlier QTL mapping study in an intraspecific Q. robur full‐sib family, polygenic inheritance was detected for leaf morphological characters that are used to discriminate between the species Quercus robur and Q. petraea. QTLs were distributed over ten linkage groups, showed a moderate effect in terms of phenotypic variance explained (PVE) in the mapping pedigree (3.6–9.6%), but accounted for a considerable amount of the parental differences. Co‐localisation of QTLs on the same linkage group in different genetic backgrounds was found for the number and percentage of intercalary veins (NV, PV) on linkage group 3 and for NV on linkage group 5, revealing a high congruence in the relative QTL positions. The generally low correspondence of the other QTLs in the different mapping pedigrees may be an effect of the genetic background and of the environment. In conclusion, leaf morphological characters were found to be under polygenic control, and a comparison to earlier published results led to the identification of two QTLs that were stable across different genetic backgrounds.
Morphological patterns of extrafloral nectaries in woody plant species of the Braziliancerrado
Authors: Machado S. R. , Morellato L. P. C. , Sajo M. G. , Oliveira P. S. 
Published: June 2008

AbstractExtrafloral nectaries are nectar‐secreting structures that are especially common among the woody flora of the Braziliancerrado, a savanna‐like vegetation. In this study, we provide morphological and anatomical descriptions of extrafloral nectaries (EFNs) occurring on vegetative and reproductive organs of several plant species from thecerrado, and discuss their function and ecological relevance. We describe the morphology and anatomy of EFNs of 40 species belonging to 15 woody families using scanning electron microscopy and light microscopy. We categorise EFNs following a structural–topographical classification, and characterise the vascularised and complex nectaries, amorphous nectaries and secretory trichomes. Fabaceae, Bignoniaceae, Malpighiaceae and Vochysiaceae were the plant families with the majority of species having EFNs. Ten species possess more than one morphotype of gland structure. Observations and experimental field studies in thecerradosupport the anti‐herbivore role of EFN‐gathering ants in this habitat. Additional morphological studies of EFNs‐bearing plants, including other growth forms (e.g.herbs and lianas), are being undertaken and will hopefully cast further light on the ecological relevance of these glands in thecerrado, especially with respect to their attractiveness to multiple visitors.
Stress hormones and abiotic stresses have different effects on antioxidants in maize lines with different sensitivity
Authors: Kellős T. , Tímár I. , Szilágyi V. , Szalai G. , Galiba G. , Kocsy G. 
Published: June 2008

AbstractThe effect of stress hormones and abiotic stress treatments on reactive oxygen species and on antioxidants was compared in two maize (Zea mays L.) lines (Penjalinan and Z7) having different stress tolerance. Following treatment with abscisic acid, salicylic acid or hydrogen peroxide, the amount of hydrogen peroxide and lipid peroxides increased, while after osmotic stress or cultivation in continuous darkness, the levels were unchanged or decreased. The higher amount of lipid peroxides in Penjalinan indicated its greater sensitivity compared to Z7. The level of the examined antioxidants was increased by nearly all treatments. Glutathione and cysteine contents were higher after salicylic acid, hydrogen peroxide and polyethylene glycol treatments and lower after application of abscisic acid, NaCl and growth in darkness in Z7 than in Penjalinan. The activity of glutathione reductase, ascorbate peroxidase, catalase and glutathione S‐transferase was higher after almost all treatments in Z7. The expression of the glutathione synthetase (EC 6.3.2.3) gene was not affected by the treatments, while the level of γ‐glutamylcysteine synthetase (EC 6.3.2.2) and glutathione reductase (EC 1.6.4.2) transcripts increased after most treatments. The two stress hormones and the stress treatments resulted in different changes in antioxidant levels in the two maize lines, which indicates the specific, stress tolerance‐dependent response of plants to the various growth regulators and adverse environmental effects that were examined.
Technical Restrictions of Computer‐Manipulated Visual Stimuli and Display Units for Studying Animal Behaviour
Authors: Baldauf Sebastian A. , Kullmann Harald , Bakker Theo C. M. 
Published: June 2008

AbstractComputer‐manipulated visual stimuli are a well‐established tool to experimentally study animal behaviour. They provide the opportunity to manipulate single or combined visual stimuli selectively, while other potentially confounding variables remain constant. A wide array of different presentation methods of artificial stimuli has been used in recent research. Furthermore, a wide range of basic hardware and software has been used to conduct experiments. The outcomes of experimental trials using computer‐manipulated visual stimuli differed among studies. Failing or contradictory results were mostly discussed in a behavioural and ecological context. However, the results sometimes may be basically flawed due to methodological traps in the experimental design. Based on characteristics and restrictions of technical standards, we discuss which kinds of computer stimuli and visual display units are available today and their suitability for experimental trials when studying animal behaviour. A computer‐manipulated stimulus displayed by a certain visual display unit may be accurate to investigate behaviour in a specific species, if various preconditions are met. However, simply due to technical characteristics of the visual display unit, the set‐up may be unsuitable for other test species. Thus, future research should critically apply the included technique, with respect to both the intended kind of stimulus and the species under investigation. If these preconditions are met, computer‐manipulated stimuli provide a high degree of standardization and the potential to display visual signals without losing a crucial amount of information from the native data.
Size‐Dependent Mating Success at Various Nutritional States in the Yellow Dung Fly
Authors: Blanckenhorn Wolf U. , Birrer Maurus , Meier Christoph M. , Reim Constanze , Teuschl Yvonne , Weibel Denise 
Published: June 2008

AbstractMating success not only depends on genetic quality, but also equally on environmental factors, most prominently food availability. We investigated the interactive effects of nutritional state and body size on mating success and copula duration in yellow dung fly males (Scathophaga stercoraria; Diptera: Scathophagidae) of three body size selection lines in the laboratory in both non‐competitive (single) and competitive (group) situations. Adults require protein and lipids from prey to reproduce, as well as sugars as an energy source for reproductive activity. We expected mating success to decrease with time because of sperm depletion (sugar treatment) and/or energy shortage (water treatment) relative to the control, prey plus sugar treatment. Based on physiological scaling, we also expected large‐line males to become depleted either sooner because of their higher energy and sperm demands, or later because of their more efficient energy use. Average mating success indeed declined over a period of 5–7 d (or 5–15 potential copulations per male), but equally for all food treatments and body size classes. Surprisingly, water‐fed and small‐line males had the highest mating probability in the non‐competitive setting, while in the competitive setting large‐line males had the highest success. Energy‐depleted males showed apparent terminal investment. Small males acquired females more readily but eventually lost them to larger males in the competitive situation. As shown before, copula duration was inversely related to body size and increased with copulation number, independent of food treatment. We conclude that sugar or prey shortage has little effect on mating success in the short term, and does not differentially affect males of different sizes.
ALVEOLAR–ARTERIAL OXYGEN GRADIENT, PNEUMONIA SEVERITY INDEX AND OUTCOMES IN PATIENTS HOSPITALIZED WITH COMMUNITY ACQUIRED PNEUMONIA
Authors: Moammar Mahmoud Q , Azam Hamad M , Blamoun Adel I , Rashid Ashraf O , Ismail Medhat , Khan M Anees , DeBari Vincent A 
Published: June 2008

SUMMARY

The alveolar–arterial oxygen gradient (ΔA–a) provides a useful assessment of ventilation/perfusion (V/Q) abnormalities. The objectives of the present study were to: (i) examine the correlation between the ΔA–a and the pneumonia severity index (PSI); and (ii) determine whether these measures were comparable in predicting clinical outcomes.
The present study was conducted at a 750‐bed teaching hospital. It examined a retrospective cohort of 255 patients with community acquired pneumonia (CAP) over a 2 year period. Association between the CAP and ΔA–a was investigated by regression models and correlation, as well as two logistic models for subjects bifurcated by low‐risk/moderate‐to‐high risk. The decision levels (DL) for both PSI and ΔA–a were then compared as predictors of both length of stay (LOS) and survival.
The correlation between PSI and ΔA–a was strong (ρ = 0.76; P < 0.0001) and was best modelled by a curvilinear relationship. Both logistic models indicated a strong association (P < 0.001) between ΔA–a and PSI and yielded an optimal DL for the ΔA–a of < 89 mmHg. Inter‐test agreement of ΔA–a with PSI was 76.9% (κ = 0.60; 95% confidence interval 0.47–0.72; P < 0.0001). At < 89 mmHg, the odds ratios for LOS were similar to those at PSI = 90 in predicting LOS in the range 3–7 days, inclusive. There was no significant difference in the ability of ΔA–a and PSI to predict survival for either the low‐ or high‐risk group (P = 0.363 and P = 0.951, respectively).
The ΔA–a correlates well with PSI and performs comparably in predicting two major outcomes in subjects hospitalized with CAP.
SHORT‐TERM TREATMENT OF STROKE‐PRONE SPONTANEOUSLY HYPERTENSIVE RATS WITH AN AT1 RECEPTOR BLOCKER PROTECTS AGAINST HYPERTENSIVE END‐ORGAN DAMAGE BY PROLONGED INHIBITION OF THE RENIN–ANGIOTENSIN SYSTEM
Authors: Hamaguchi Rika , Takemori Kumiko , Inoue Takao , Masuno Kouichi , Ito Hiroyuki 
Published: June 2008

SUMMARY

The aim of the present study was to investigate the effects of short‐term treatment with an AT1 receptor blocker (ARB) on amelioration of hypertensive end‐organ damage in stroke‐prone spontaneously hypertensive rats (SHRSP).
Male SHRSP were divided into two groups: (i) an ARB‐treated group; and (ii) a control group. Candesartan (1 mg/kg per day) was administered orally from 6 to 11 weeks of age. At 20 weeks of age, plasma renin activity (PRA), angiotensin II concentrations, angiotensin‐converting enzyme (ACE) activity and hydroperoxide content were measured. Expression of intercellular adhesion molecule (ICAM)‐1, renin, AT1 and AT2 receptors was investigated by reverse transcription–polymerase chain reaction.
Blood pressure in the ARB group was slightly lower at 7, 8, 11, 13–15 and 18 weeks of age, but no significant difference in blood pressure was found between the ARB and control groups at 20 weeks of age. All rats in the control group had cerebral oedema, whereas no lesions were found in the ARB group. In the ARB group, PRA, AII and hydroperoxide content were lower than in the control group. In the ARB‐treated group, lower ICAM‐1 expression was found in the cerebral cortex and slightly, albeit not significantly, lower expression of renin was found in the kidney. In contrast, AT1 receptor expression in the cerebrum and kidney was higher in the ARB group compared with the control group.
These results indicate that short‐term treatment of SHRSP with ARB at a young age is effective in preventing cerebral oedema after maturation. Such beneficial effects of ARB may be due, in part, to decreased blood pressure and is likely mainly due to inhibition of total circulating and local renin–angiotensin systems.
EFFECT OF INHIBITION OF NEURONAL NITRIC OXIDE SYNTHASE AND l‐ARGININE SUPPLEMENTATION ON RENAL ISCHAEMIA–REPERFUSION INJURY AND THE RENAL NITRIC OXIDE SYSTEM
Authors: Rusai Krisztina , Fekete Andrea , Szebeni Beáta , Vannay Ádám , Bokodi Géza , Müller Veronika , Viklicky Ondrej , Bloudickova Silvie , Rajnoch Jan , Heemann Uwe , Reusz György , Szabó András , Tulassay Tivadar , Szabó Attila J 
Published: June 2008

SUMMARY

The role of nitric oxide synthases (NOS) and the nitric oxide (NO) substrate l‐arginine in renal ischaemia–reperfusion (I/R) has been studied extensively. However, the results reported are often controversial. In the present study, we examined the effects of the neuronal (n) NOS inhibitor 7‐nitroindazole (7‐NI) and l‐arginine administration on renal I/R injury and the renal NO system in rats.
Following 7 days pretreatment with 7‐NI (50 mg/kg per day), l‐arginine (2 g/kg per day) or vehicle (dimethylsulphoxide : sesame oil, 1 : 9), the left renal vascular pedicles were clamped for 50 min in male Sprague‐Dawley rats and kidneys were removed 24 h after reperfusion (n = 7/group).
Neither 7‐NI nor l‐arginine had any effect on parameters of renal function, the grade of tissue injury or the number of terminal deoxyribonucleotidyl transferase‐mediated dUTP–digoxigenin nick end‐labelling (TUNEL)‐positive tubular cells compared with vehicle‐treated rats. 7‐Nitroindazole decreased nNOS mRNA expression and inducible (i) NOS protein levels, but had no effect on endothelial NOS expression. l‐Arginine supplementation increased mRNA expression of all NOS isoforms, but only increased protein expression of iNOS.
The results of the present study demonstrate that selective inhibition of nNOS has no effect on renal injury, indicating that nNOS does not play a central role in the pathophysiology of renal I/R. In addition, although l‐arginine has no effect on renal I/R injury in the model used in the present study, its administration increases the mRNA expression of NOS isoforms.
CENTRAL CHOLINE SUPPRESSES PLASMA RENIN RESPONSE TO GRADED HAEMORRHAGE IN RATS
Authors: Isbil‐Buyukcoskun Naciye , Ilcol Yesim O , Cansev Mehmet , Hamurtekin Emre , Ozluk Kasim , Ulus Ismail H 
Published: June 2008

SUMMARY

Central administration of choline increases blood pressure in normotensive and hypotensive states by increasing plasma concentrations of vasopressin and catecholamines. We hypothesized that choline could also modulate the renin–angiotensin pathway, the third main pressor system in the body.
Plasma renin activity (PRA), which serves as an index of the function of the peripheral renin–angiotensin system, was determined in rats subjected to graded haemorrhage following central choline administration.
Intracerebroventricular (i.c.v.) injection of choline (12.5–150 µg), a precursor of the neurotransmitter acetylcholine (ACh), inhibited the increase in PRA in rats subjected to graded haemorrhage by sequential removal of 0.55 mL blood/100 g bodyweight. Choline, in the range 50–150 µg, increased blood pressure.
Intraperitoneal (i.p.) administration of 150 µg choline failed to alter blood pressure and plasma renin responses to graded haemorrhage. Administration of a higher dose (90 mg/kg, i.p.) of choline decreased blood pressure and enhanced PRA in the first two blood samples obtained during the graded haemorrhage. Physostigmine (10 µg, i.c.v.), ACh (10 µg, i.c.v.), carbamylcholine (10 µg, i.c.v.) and cytidine 5′‐diphosphocholine (CDP‐choline; 250 µg, i.c.v.) increased blood pressure and attenuated plasma renin responses to graded haemorrhage.
Inhibition of PRA by i.c.v. choline was abolished by i.c.v. pretreatment with mecamylamine (50 µg), but not atropine (10 µg). Blood pressure responses to choline (150 µg) were attenuated by pretreatment with both mecamylamine and atropine.
Inhibition of PRA in response to central choline administration was associated with enhanced plasma vasopressin and catecholamine responses to graded haemorrhage. Pretreatment of rats with a vasopressin antagonist reversed central choline‐induced inhibition of plasma renin responses to graded haemorrhage without altering the blood pressure response.
In conclusion, central administration of choline inhibits the plasma renin response to graded haemorrhage. Nicotinic receptor activation and an increase in plasma vasopressin appear to be involved in this effect.
IDENTIFICATION OF A NOVEL REPRESSOR ELEMENT IN THE CYCLO‐OXYGENASE‐2 PROMOTER AND ITS NUCLEAR BINDING PROTEIN
Authors: Yang Xiaomin , Lin Ling , Zhang Xiongfei , Ji Yong , Lv Jinghuan , Zhu Yunxia , Yin Yongmei , Sun Yujie , Han Xiao 
Published: June 2008

SUMMARY

Cyclo‐oxygenase‐2 (COX‐2) has important functions in many diseases. Although its transcriptional regulation has been investigated in considerable detail, some important elements remain unknown. The aim of the present study was to demonstrate the existence of a novel repressor element in the mouse COX‐2 promoter and characterize some of its binding proteins.
In order to identify the repressor element, the activity of the mouse COX‐2 promoter was investigated in the pancreatic β‐cell line RINm5F using a series of deletion and mutant constructs. The ability of nuclear proteins to bind to this repressor element was then determined by an electrophoretic mobility shift assay and the proteins binding to this repressor element were purified and identified by mass spectrometry. One of the nuclear proteins identified was overexpressed to examine its inhibitory effect on COX‐2 promoter activity.
We found a novel repressor element located from nucleotides –655 to –632 of the mouse COX‐2 promoter region. Some proteins from RINm5F cell nuclear extracts bound to this element, one of which was identified as non‐POU‐domain‐containing, octamer‐binding protein (NonO). Overexpression of NonO significantly inhibited wild‐type COX‐2 promoter activity, but had no effect when the repressor element was mutated.
In conclusion, we have demonstrated that a regulatory ‘spot’ is present in the COX‐2 promoter. This provides additional data on COX‐2 gene regulation and may provide an insight into the clinical treatment of diseases where COX‐2 is highly expressed.
INHIBITION OF LEFT VENTRICULAR REMODELLING IN SPONTANEOUSLY HYPERTENSIVE RATS by Gαq‐PROTEIN CARBOXYL TERMINUS IMITATION POLYPEPTIDE GCIP‐27 IS NOT ENTIRELY DEPENDENT ON BLOOD PRESSURE
Authors: Wang Xiu‐Qin , Zhang Hai‐Gang , Cheng Yi‐Qun , Li Xiao‐Hui 
Published: June 2008

SUMMARY

The Gq‐protein is located at the convergent point in the signal transduction pathway that leads to ventricular remodelling. In G‐protein signalling pathways, the carboxyl terminus of the Gα‐subunit plays a vital role in G‐protein–receptor interaction. The aim of the present study was to explore the effects of a synthetic Gαq carboxyl terminus imitation peptide, namely GCIP‐27, on left ventricular (LV) remodelling and blood pressure in spontaneous hypertensive rats (SHR).
In the present study, 10, 30 or 90 µg/kg, i.p., GCIP‐27 was administered for 8 weeks to SHR. In addition, another two groups of SHR were treated with either 6 mg/kg losartan or vehicle (saline). Wistar‐Kyoto rats were used as controls. Systolic blood pressure (SBP) was measured using the standard tail‐cuff method once every 2 weeks. At the end of the experiment, the LV mass index (LVMI) was evaluated. In addition, LV structure and function, collagen content, microstructure and ultrastructure were examined using echocardiography, the hydroxyproline assay, routine light microscopy and transmission electron microscopy, respectively.
In the losartan‐ and GCIP‐27 (10, 30 and 90 µg/kg)‐treated groups, SBP was decreased significantly compared with that of the vehicle (saline) group. However, even at the highest concentration used, the hypotensive effect of GCIP‐27 was weaker than that of losartan. For example, after 8 weeks treatment, SBP had decreased by 30.4% in the losartan‐treated group compared with decreases of 10.5, 13.1 and 18.5% in the 10, 30 and 90 µg/kg GCIP‐27‐treated groups, respectively.
Both GCIP‐27 (10, 30 and 90 µg/kg) and losartan (6 mg/kg) significantly reduced LV posterior wall thickness, the thickness of the interventricular septum, collagen content and LVMI, with the effects of GCIP‐27 at all three concentrations tested being greater than those of losartan.
In conclusion, GCIP‐27 effectively attenuates LV remodelling in SHR and the antiremodelling effect may not be dependent entirely on decreases in blood pressure.