bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predictiveness of antenatal umbilical artery Doppler for adverse pregnancy outcome in small‐for‐gestational‐age babies according to customised birthweight centiles: population‐based study
Authors: Figueras F , Eixarch E , Gratacos E , Gardosi J 
Published: March 2008

Objective  To examine the relationship between smallness at birth and the predictive value of umbilical artery Doppler.Design  Retrospective cohort.Setting  Tertiary referral university hospital, Barcelona.Population  A total of 7645 singleton pregnancies delivered between January 2002 and June 2004.Methods  The associations with adverse outcome were assessed for small‐for‐gestational‐age (SGA) babies according to customised standards who had normal and abnormal umbilical artery Doppler.Main outcome measures  Neonatal morbidity and perinatal mortality.Results  Of the 369 SGA fetuses that had been identified antenatally, 70 (19%) had an abnormal umbilical artery Doppler and the babies from these pregnancies had a higher risk for neonatal morbidity when compared with babies with normal birthweight (OR 3.99, 95% CI 1.04–11.03). However, the remaining 299 (81%) fetuses with normal umbilical artery Doppler also had an elevated risk of neonatal morbidity (OR 2.26, 95% CI 1.04–4.39). Overall, many of the instances of adverse outcome associated with smallness for gestational age were attributable to the group with normal Doppler than to the group with abnormal Doppler.Conclusion  Normal antenatal umbilical artery Doppler cannot be taken as an indicator of low risk in pregnancies where the fetus is SGA according to customised percentiles.
Induction of premature senescence in cardiomyocytes by doxorubicin as a novel mechanism of myocardial damage
Authors: Maejima Yasuhiro , Adachi Susumu , Ito Hiroshi , Hirao Kenzo , Isobe Mitsuaki 
Published: March 2008

SummaryCellular senescence is an important phenomenon in decreased cellular function. Recently, it was shown that cellular senescence is induced in proliferating cells within a short period of time by oxidative stresses. This phenomenon is known as premature senescence. However, it is still unknown whether premature senescence can be also induced in cardiomyocytes. The aim of the present study was to investigate whether a senescence‐like phenotype can be induced in cardiomyocytes by oxidative stress. In cardiomyocytes obtained from aged rats (24 months of age), the staining for senescence‐associated β‐galactosidase increased significantly and the protein or RNA levels of cyclin‐dependent kinase inhibitors increased compared to those of young rats. Decreased cardiac troponin I phosphorylation and telomerase activity were also observed in aged cardiomyocytes. Treatment of cultured neonatal rat cardiomyocytes with a low concentration of doxorubicin (DOX) (10−7 mol L−1) did not induce apoptosis but did induce oxidative stress, which was confirmed by 2′,7′‐dichlorofluorescin diacetate staining. In DOX‐treated neonatal cardiomyocytes, increased positive staining for senescence‐associated β‐galactosidase, cdk‐I expression, decreased cardiac troponin I phosphorylation, and decreased telomerase activity were observed, as aged cardiomyocytes. Alterations in mRNA expression typically seen in aged cells were observed in DOX‐treated neonatal cardiomyocytes. We also found that promyelocytic leukemia protein and acetylated p53, key proteins involved in stress‐induced premature senescence in proliferating cells, were associated with cellular alterations of senescence in DOX‐treated cardiomyocytes. In conclusion, cardiomyocytes treated with DOX showed characteristic changes similar to cardiomyocytes of aged rats. promyelocytic leukemia‐related p53 acetylation may be an underlying mechanism of senescence‐like alterations in cardiomyocytes. These findings indicate a novel mechanism of myocardial dysfunction induced by oxidative stress.
Stem Cell Review Series: Role of neurogenesis in age‐related memory disorders
Authors: Drapeau Elodie , Nora Abrous Djoher 
Published: March 2008

SummaryNeuroplasticity is characterized by growth and branching of dendrites, remodeling of synaptic contacts, and neurogenesis, thus allowing the brain to adapt to changes over time. It is maintained in adulthood but strongly repressed during aging. An age‐related decline in neurogenesis is particularly pronounced in the two adult neurogenic areas, the subventricular zone and the dentate gyrus. This age‐related decline seems to be attributable mainly to limited proliferation, associated with an age‐dependent increase in quiescence and/or a lengthening of the cell cycle, and is closely dependent on environmental changes. Indeed, when triggered by appropriate signals, neurogenesis can be reactivated in senescent brains, thus confirming the idea that the age‐related decrease in new neuron production is not an irreversible, cell‐intrinsic process. The coevolution of neurogenesis and age‐related memory deficits – especially regarding spatial memory – during senescence supports the idea that new neurons in the adult brain participate in memory processing, and that a reduction in the ability to generate new neurons contributes to the appearance of memory deficits with advanced age. Furthermore, the age‐related changes in hippocampal plasticity and function are under environmental influences that can favor successful or pathological aging. A better understanding of the mechanisms that regulate neurogenesis is necessary to develop new therapeutic tools to cure or prevent the development of memory disorders that may appear during the course of aging in some individuals.
Effect of fluconazole prophylaxis on the incidence of invasive candida infections and bacteraemias in patients with acute leukaemia
Authors: Nihtinen Anne , Anttila Veli‐Jukka , Elonen Erkki , Juvonen Eeva , Volin Liisa , Ruutu Tapani 
Published: March 2008

AbstractObjectives:  The efficacy of fluconazole prophylaxis to prevent invasive candida infections in patients with acute leukaemia receiving chemotherapy is not clear. Fluconazole prophylaxis might increase the number of bacteraemias and cause outbreaks of non‐albicans yeast infections. A retrospective single‐centre study was conducted to investigate the effect of fluconazole prophylaxis on the incidence and the species of invasive candida infections and on the number of bacteraemias.Methods:  All 1089 adult acute leukaemia patients treated with chemotherapy in 1978–2004 at Helsinki University Central Hospital were included. Data of positive blood cultures, histological samples, and fungal cultures was collected from the patient charts and the microbiology laboratory database. Fluconazole prophylaxis was used in all patients from 2000 on.Results:  Invasive candida infection was diagnosed in 74 out of 847 patients (8.7%) treated without fluconazole prophylaxis and in four out of 242 patients (1.6%) receiving the prophylaxis (P < 0.001). The incidence of non‐albicans infections did not increase in the fluconazole prophylaxis group. A larger proportion of patients developed bacteraemias in the prophylaxis group (65%) compared to the non‐prophylaxis group (52%) (P < 0.001). A trend towards more gram‐positive bacteraemias was seen in the prophylaxis group. Invasive candida infections were more common in patients with acute lymphoblastic leukaemia than those with acute myeloid leukaemia, 10.5% vs. 5.9% (P = 0.008).Conclusions:  Fluconazole prophylaxis was effective in preventing invasive candida infections in patients with acute leukaemia without increasing non‐albicans infections. The risk of bacteraemias, however, increased
Non‐pathogenic commensal Escherichia coli bacteria can inhibit degranulation of mast cells
Authors: Magerl Markus , Lammel Verena , Siebenhaar Frank , Zuberbier Torsten , Metz Martin , Maurer Marcus 
Published: March 2008

AbstractBackground:  The mast cell’s (MC) ability to rapidly release presynthesized mediators allows it to play a critical role in the immune system’s first‐line response to pathogens. Although recent research has illuminated the role of MCs in bacterial infection, little is known about how non‐pathogenic bacteria influence MC responses.Objective:  To characterize the influence of non‐pathogenic Escherichia coli bacteria on MCs.Results:  High concentrations of live E. coli strongly down‐modulated the degranulation of murine peritoneal MCs under all activator conditions. Bacteria did not induce MC degranulation by themselves, and staining of MCs showed they were still entirely viable. Dead bacteria and bacterial supernatant had no effect on MC degranulation. Ex vivo experiments confirmed that E. coli exposure down‐modulates subsequently induced MC degranulation and that this effect lasts for up to a few days after exposure.Conclusion:  Our results show that high doses of non‐pathogenic E. coli bacteria can function as a strong, direct inhibitor of MC degranulation. This suggests a possible basis for future antiallergic treatment or prophylaxis with commensal bacteria, i.e. probiotics.
Growth effects of botulinum toxin type A injected into masseter muscle on a developing rat mandible
Authors: Kim J‐Y , Kim S‐T , Cho S‐W , Jung H‐S , Park K‐T , Son H‐K 
Published: March 2008

Objectives:  Botulinum toxin type A (BTX‐A) reduces the muscular contractions by temporarily inhibiting the release of acetylcholine at the neuromuscular junction. The purpose of this study was to investigate the effects of the BTX‐A injected into the masseter muscle of a developing rat mandible.Materials and methods:  Four‐week‐old male (no. 80) Sprague–Dawley rats were divided into four groups: control group, saline group, BTX‐A group and baseline control group. Rats of baseline group were sacrificed at 0 day to provide baseline values of the mandibular measurements. The masseter muscle of rats in the saline and the BTX‐A group were administered with saline and BTX‐A solutions respectively. Experimental animals were sacrificed after 4 weeks.Results:  The BTX‐A group demonstrated smaller mandibular dimension compared with the other groups (P < 0.05). Their condylar cartilages showed increased apoptosis at the proliferation stage of the reserve zone and masseter muscle fibers demonstrated atrophic changes.Conclusions:  The result demonstrated BTX‐A influence on inhibitory action of the developing mandible because of apoptosis at the proliferation stage of the reserve zone of the condylar cartilage in developing rat mandible.
Figuring it Out in the Moment: A Theory of Unregulated Care Providers' Knowledge Utilization in Dementia Care Settings
Authors: Janes Nadine , Sidani Souraya , Cott Cheryl , Rappolt Susan 
Published: March 2008

ABSTRACT Background: Within the context of knowledge translation, the disconnect between the results of research and the practice patterns of nursing care providers has not been reported in the context of institutional dementia care practice. Therefore, little is known about how knowledge about best dementia care practice, defined broadly as the person‐centered approach, gets used by institutional nursing care providers. Aim: Unregulated care providers provide the majority of nursing care for older people with Alzheimer's disease and related disorders living in long‐term care facilities. The purpose of this grounded theory study was to explore the process whereby these workers use knowledge about person‐centered care in their dementia care practice. Methods: Transcribed data from tape‐recorded interviews with 20 unregulated care providers among eight long‐term care facilities in Ontario, Canada, were coded and categorized at progressively more abstract levels until concepts and the relationships among them were integrated in a middle‐range theory of knowledge utilization. Results: The theory of Figuring it Out in the Moment illustrates how unregulated care providers in dementia care settings practice in the context of unpredictability, variability, and personal threat. Their use of knowledge about person‐centered care is dependent on the existence of certain individual and relational conditions that interrelate with four separate, but interconnected, phases of clinical decision‐making and action. Conclusions: As a middle‐range theory, Figuring it Out in the Moment is concrete and pragmatic information for promoting evidence‐based dementia care not included in existing overarching knowledge utilization frameworks. Areas for further investigation include how knowledge utilization is conceptualized, as well as the influences of practitioners' clinical decision‐making, the nature of caregiving with particular client populations, and the characteristics of individuals alone and in relationship on the utilization of best practice knowledge.
PJ34, a Poly Adenosine Diphosphate‐Ribose Polymerase Inhibitor, Attenuates Chromate‐Induced Nephrotoxicity
Authors: Yam‐Canul Paola , Chirino Yolanda Irasema , Sánchez‐González Dolores Javier , Martínez‐Martínez Claudia María , Cruz Cristino , Pedraza‐Chaverri José 
Published: March 2008

Abstract:  Potassium dichromate (K2Cr2O7)‐induced nephrotoxicity is associated with oxidative stress. In addition, the activation of the polyadenosine diphosphate‐ribose [poly(ADP‐ribose)] polymerase‐1 (PARP‐1) plays a role in the pathophysiology of some diseases associated with oxidative stress. To clarify the potential role of PARP‐1 in this experimental model, N‐(6‐oxo‐5,6‐dihydro‐phenanthridin‐2‐yl)‐N,N‐dimethyacetamide HCl (PJ34), a highly specific inhibitor of this enzyme, was used. Nephrotoxicity was induced in rats by a single sc injection of K2Cr2O7; studies were performed 2 days later. PJ34 was given intraperitoneally (15 mg/kg) 1 hr before and 1, 5, 24, 26, 31 and 46 hr after K2Cr2O7 injection. Nephrotoxicity was evaluated by histological analysis and by measuring blood urea nitrogen, serum creatinine, serum glutathione peroxidase activity and urinary excretion of N‐acetyl‐β‐d‐glucosaminidase. PARP‐1 activation was evaluated by the immunostaining of poly(ADP‐ribose). In addition, the following markers of oxidative stress were evaluated: 3‐nitrotyrosine, 4‐hydroxy‐2‐nonenal, malondialdehyde and protein carbonyl content. K2Cr2O7 increased poly(ADP‐ribose) content suggesting the PARP‐1 activation in this model. PJ34 significantly ameliorated the K2Cr2O7‐induced: (i) nephrotoxicity, (ii) poly(ADP‐ribose) accumulation and (iii) oxidative stress. It is concluded that PARP‐1 is activated and involved, at least in part, in K2Cr2O7‐induced nephrotoxicity in rats.
In vitroInhibition of CYP3A4 Metabolism and P‐Glycoprotein‐Mediated Transport by Trade Herbal Products
Authors: Hellum Bent H. , Nilsen Odd Georg 
Published: March 2008

Abstract: Extracts of six commonly used commercially available herbal products, St. John's wort, common valerian, common sage,Ginkgo biloba,Echinacea purpureaand horse chestnut were investigated for theirin vitroinhibitory potential of CYP3A4 mediated metabolism and P‐glycoprotein efflux transport activity. C‐DNA baculovirus expressed CYP3A4 and Caco‐2 cells were used. Ketoconazole and verapamil were applied as positive control inhibitors, respectively. A validated high‐performance liquid chromatography methodology was used to quantify the formation of 6‐OH‐testosterone and scintillation counting was used to quantify the transport of3H‐digoxin. All the investigated herbs inhibited CYP3A4 activity. St. John's wort was the strongest inhibiting herb with an IC50value of 15.4 µg/ml, followed by common sage,Ginkgo biloba, common valerian, horse chestnut andEchinacea purpurea. All herbs also inhibited P‐glycoprotein activity.Ginkgo bilobawas the strongest inhibiting herb, inhibiting the net digoxin flux with an IC50value of 23.6 µg/ml, followed by St. John's wort, horse chestnut, common sage, common valerian andEchinacea purpurea. No correlation was found between the herbs inhibitory potentials towards CYP3A4 and P‐glycoprotein activities.Ginkgo biloba, horse chestnut and common sage, besides St. John's wort, are suggested candidates forin vivointestinal herb‐drug pharmacokinetic interactions.
Genetic approaches to sustainable pest management in sugar beet (Beta vulgaris)
Authors: Zhang C.‐L. , Xu D.‐C. , Jiang X.‐C. , Zhou Y. , Cui J. , Zhang C.‐X. , Chen D.‐F. , Fowler M.R. , Elliott M.C. , Scott N.W. , Dewar A.M. , Slater A. 
Published: March 2008

AbstractSugar beet (Beta vulgaris) is an important arable crop, traditionally used for sugar extraction, but more recently, for biofuel production. A wide range of pests, including beet cyst nematode (Heterodera schachtii), root‐knot nematodes (Meloidogyne spp.), green peach aphids (Myzus persicae) and beet root maggot (Tetanops myopaeformis), infest the roots or leaves of sugar beet, which leads to yield loss directly or through transmission of beet pathogens such as viruses. Conventional pest control approaches based on chemical application have led to high economic costs. Development of pest‐resistant sugar beet varieties could play an important role towards sustainable crop production while minimising environmental impact. Intensive Beta germplasm screening has been fruitful, and genetic lines resistant to nematodes, aphids and root maggot have been identified and integrated into sugar beet breeding programmes. A small number of genes responding to pest attack have been cloned from sugar beet and wild Beta species. This trend will continue towards a detailed understanding of the molecular mechanism of insect–host plant interactions and host resistance. Molecular biotechnological techniques have shown promise in developing transgenic pest resistance varieties at an accelerated speed with high accuracy. The use of transgenic technology is discussed with regard to biodiversity and food safety.
Fitting orbits to tidal streams
Authors: Binney James 
Published: March 2008

Abstract
Recent years have seen the discovery of many tidal streams through the Galaxy. Relatively straightforward observations of a stream allow one to deduce three phase-space coordinates of an orbit. An algorithm is presented that reconstructs the missing phase-space coordinates from these data. The reconstruction starts from assumed values of the Galactic potential and a distance to one point on the orbit, but with noise-free data the condition that energy be conserved on the orbit enables one to reject incorrect assumptions. The performance of the algorithm is investigated when errors are added to the input data that are comparable to those in published data for the streams of Pal 5. It is found that the algorithm returns distances and proper motions that are accurate to of the order of 1 per cent, and enables one to reject quite resonable but incorrect trial potentials. In practical applications, it will be important to minimize errors in the imput data, and there is considerable scope for doing this.
On the relation between the radial alignment of dark matter subhaloes and host mass in cosmological simulations
Authors: Knebe Alexander , Draganova Nadya , Power Chris , Yepes Gustavo , Hoffman Yehuda , Gottlöber Stefan , Gibson Brad K. 
Published: March 2008

Abstract
We explore the dependence of the radial alignment of subhaloes on the mass of the host halo they orbit in. As the effect is seen on a broad range of scales including massive clusters as well as galactic systems it only appears natural to explore this phenomenon by means of cosmological simulations covering the same range in masses. We have 25 well resolved host dark matter haloes at our disposal ranging from 1015h−1 M⊙ down to 1012h−1 M⊙ each consisting of order of a couple of million particles within the virial radius. We observe that subhaloes tend to be more spherical than isolated objects. Both the distributions of sphericity and triaxiality of subhaloes are Gaussian-distributed with peak values of 〈s〉≈ 0.80 and 〈T〉≈ 0.56, irrespective of host mass. Interestingly, we note that the radial alignment is independent of host halo mass and the distribution of cos θ (i.e. the angle between the major-axis Ea of each subhalo and the radius vector of the subhalo in the reference frame of the host) is well fitted by a simple power law P(cos θ) ∝ cos4θ with the same fitting parameters for all host haloes.
CONSID: A Toolbox for Contaminant Source Identification
Authors: Sun Alexander Y. 
Published: March 2008

AbstractModel‐based contaminant source identification plays an important role in effective site remediation. In this article, a contaminant source identification toolbox (CONSID) is introduced as a framework for solving contaminant source identification problems. It is known that the presence of various types of model uncertainties can severely undermine the performance of many existing source estimators. The current version of CONSID consists of two robust estimators for recovering source release histories under model uncertainty; one was developed in the deterministic framework and the other in the stochastic framework. To use the robust estimators provided in CONSID, the user is required to have only modest prior knowledge about the model uncertainty and be able to estimate the bound of model deviations resulting from the uncertainty. The toolbox is designed so that other source estimators can be added easily. A step‐by‐step guidance for using CONSID is described and an example is provided.
Implications of Rate‐Limited Mass Transfer for Aquifer Storage and Recovery
Authors: Culkin Sean L. , Singha Kamini , Day‐Lewis Frederick D. 
Published: March 2008

AbstractPressure to decrease reliance on surface water storage has led to increased interest in aquifer storage and recovery (ASR) systems. Recovery efficiency, which is the ratio of the volume of recovered water that meets a predefined standard to total volume of injected fluid, is a common criterion of ASR viability. Recovery efficiency can be degraded by a number of physical and geochemical processes, including rate‐limited mass transfer (RLMT), which describes the exchange of solutes between mobile and immobile pore fluids. RLMT may control transport behavior that cannot be explained by advection and dispersion. We present data from a pilot‐scale ASR study in Charleston, South Carolina, and develop a three‐dimensional finite‐difference model to evaluate the impact of RLMT processes on ASR efficiency. The modeling shows that RLMT can explain a rebound in salinity during fresh water storage in a brackish aquifer. Multicycle model results show low efficiencies over one to three ASR cycles due to RLMT degrading water quality during storage; efficiencies can evolve and improve markedly, however, over multiple cycles, even exceeding efficiencies generated by advection‐dispersion only models. For an idealized ASR model where RLMT is active, our simulations show a discrete range of diffusive length scales over which the viability of ASR schemes in brackish aquifers would be hindered.