bluuebunny/crossref_metadata_2025_split huggingface dataset:
Haemodynamic influences on kidney oxygenation: Clinical implications of integrative physiology
Authors: Evans Roger G , Ince Can , Joles Jaap A , Smith David W , May Clive N , O'Connor Paul M , Gardiner Bruce S 
Published: November 2012

Summary

Renal blood flow, local tissue perfusion and blood oxygen content are the major determinants of oxygen delivery to kidney tissue. Arterial pressure and segmental vascular resistance influence kidney oxygen consumption through effects on glomerular filtration rate and sodium reabsorption.

Diffusive shunting of oxygen from arteries to veins in the cortex and from descending to ascending vasa recta in the medulla limits oxygen delivery to renal tissue. Oxygen shunting depends on the vascular network, renal haemodynamics and kidney oxygen consumption. Consequently, the impact of changes in renal haemodynamics on tissue oxygenation cannot necessarily be predicted intuitively and, instead, requires the integrative approach offered by computational modelling and multiple measuring modalities.

Tissue hypoxia is a hallmark of acute kidney injury (AKI) arising from multiple initiating insults, including ischaemia–reperfusion injury, radiocontrast administration, cardiopulmonary bypass surgery, shock and sepsis. Its pathophysiology is defined by inflammation and/or ischaemia resulting in alterations in renal tissue oxygenation, nitric oxide bioavailability and oxygen radical homeostasis. This sequence of events appears to cause renal microcirculatory dysfunction, which may then be exacerbated by the inappropriate use of therapies common in peri‐operative medicine, such as fluid resuscitation.

The development of new ways to prevent and treat AKI requires an integrative approach that considers not just the molecular mechanisms underlying failure of filtration and tissue damage, but also the contribution of haemodynamic factors that determine kidney oxygenation. The development of bedside monitors allowing continuous surveillance of renal haemodynamics, oxygenation and function should facilitate better prevention, detection and treatment of AKI.
The role of bacterial outer membrane vesicles for intra‐ and interspecies delivery
Authors: Berleman James , Auer Manfred 
Published: November 2012

SummaryAn increasing number of Gram‐negative bacteria have been observed to secrete outer membrane vesicles (OMVs). Many mysteries remain with respect to OMV formation, the regulation of OMV content and mode of targeting and fusion. Bacterial OMVs appear to serve a variety of purposes in intra‐ and interspecies microbial extracellular activities. OMVs have been shown to mediate cell‐to‐cell exchange of DNA, protein and small signalling molecules. The impact of such material exchanges on microbial communities and pathogenic processes, including the delivery of toxins at high concentration through OMVs, is discussed. This rather recent aspect of microbial ecology is likely to remain an important area of research as an in‐depth understanding of OMVs may allow new approaches for combating bacterial infections and provide new routes for selective drug delivery.
The phylogeographic pattern of Francisella tularensis in Sweden indicates a Scandinavian origin of Eurosiberian tularaemia
Authors: Karlsson Edvin , Svensson Kerstin , Lindgren Petter , Byström Mona , Sjödin Andreas , Forsman Mats , Johansson Anders 
Published: November 2012

SummaryPrevious studies of the causative agent of tularaemia, Francisella tularensis have identified phylogeographic patterns suggestive of environmental maintenance reservoirs. To investigate the phylogeography of tularaemia in Sweden, we selected 163 clinical isolates obtained during 1995–2009 in 10 counties and sequenced one isolate's genome to identify new genetic markers. An improved typing scheme based on two indels and nine SNPs was developed using hydrolysis or TaqMan MGB probe assays. The results showed that much of the known global genetic diversity of F. tularensis subsp. holarctica is present in Sweden. Thirteen of the 163 isolates belonged to a new genetic group that is basal to all other known members of the major genetic clade B.I, which is spread across the Eurosiberian region. One hundred and twenty‐five of the 163 Swedish isolates belonged to B.I, but individual clades' frequencies differed from county to county (P < 0.001). Subsequent analyses revealed a correlation between genotype variation over time and recurrent outbreaks at specific places, supporting the ‘maintenance reservoir’ environmental maintenance hypothesis. Most importantly, the findings reveal the presence of diverse source populations of F. tularensis subsp. holarctica in Sweden and suggest a historical spread of the disease from Scandinavia to other parts of Eurosiberia.
Emerging role of roots in plant responses to aboveground insect herbivory
Authors: Nalam Vamsi J. , Shah Jyoti , Nachappa Punya 
Published: November 2012

AbstractPlants have evolved complex biochemical mechanisms to counter threats from insect herbivory. Recent research has revealed an important role of roots in plant responses to above ground herbivory (AGH). The involvement of roots is integral to plant resistance and tolerance mechanisms. Roots not only play an active role in plant defenses by acting as sites for biosynthesis of various toxins and but also contribute to tolerance by storing photoassimilates to enable future regrowth. The interaction of roots with beneficial soil‐borne microorganisms also influences the outcome of the interaction between plant and insect herbivores. Shoot‐to‐root communication signals are critical for plant response to AGH. A better understanding of the role of roots in plant response to AGH is essential in order to develop a comprehensive picture of plant‐insect interactions. Here, we summarize the current status of research on the role of roots in plant response to AGH and also discuss possible signals involved in shoot‐to‐root communication.
Effects of larval size and hydrodynamics on the growth rates of the black fly Simulium tribulatum
Authors: BRANNIN Michelle T. , O'DONNELL Mary Kate , FINGERUT Jonathan 
Published: November 2012

AbstractBlack flies are ubiquitous and important members of lotic ecosystems. Size is known to affect many aspects of their life in the aquatic larval stage, including intraspecific competition for feeding sites. As filter feeders, flow affects their ability to feed and reach sufficiently fast flow. This, in turn, can lead to risky fluid‐mediated dispersal behavior in search of better conditions. It is surprising, therefore, that little information is available regarding how physiological and environmental factors combine to affect larval growth rates. The present study determines the relative growth rates of small (0.6 mm) and large (approximately 4 mm) larvae in laboratory flumes designed to produce spatially homogeneous and temporally consistent flow regimes at ecologically relevant velocities (44 and 64 cm/s). Our results indicate that size and flow both influence growth rates and that the 2 interact significantly. Young larvae exhibit faster growth rates and a greater positive response to increased flow speed. This result might help explain why smaller larvae have a greater propensity to disperse than larger larvae: the benefit of increased growth rate that they receive from relocating to faster flow might balance the risks inherent in dispersal.
The Pseudomonas putidaHskA hybrid sensor kinase controls the composition of the electron transport chain
Authors: Sevilla Emma , Silva‐Jiménez Hortencia , Duque Estrella , Krell Tino , Rojo Fernando 
Published: November 2012

SummarySensor kinases play a key role in sensing and responding to environmental and physiological signals in bacteria. In this study we characterized a previously unknown orphan hybrid sensor kinase from Pseudomonas putida, which is conserved in several Pseudomonads. Inactivation of the gene coding for this sensor kinase, which we have named HskA, modified the expression of at least 85 genes in cells growing in a complete medium. HskA showed a strong influence on the composition of the electron transport chain. In cells growing exponentially in a complete medium, the absence of HskA led to a significant reduction in the expression of the genes coding for the bc1 complex and for the CIO and Cbb3‐1 terminal oxidases. In stationary phase cells, however, lack of HskA caused a higher expression of the Cyo terminal oxidase and a lower expression of the Aa3 terminal oxidase. The HskA polypeptide shows two PAS (signal‐sensing) domains, a transmitter domain containing the invariant phosphorylatable histidine and an ATP binding site, and a receiver domain containing the conserved aspartate capable of transphosphorylation, but lacks an Hpt module. It is therefore a hybrid sensor kinase. Phosphorylation assays showed that purified HskA undergoes autophosphorylation in the presence of ATP.
The LMA‐SupremeTM as an intubation conduit in patients with known difficult airways: a prospective evaluation study
Authors: VAN ZUNDERT T. C. R. V. , WONG D. T. , VAN ZUNDERT A. A. J. 
Published: November 2012

BackgroundMany extraglottic airway devices allow the direct passage of an adult‐sized tracheal tube, but this is not possible with the LMA‐SupremeTM. We evaluated the feasibility of using the LMA‐SupremeTM as a conduit for intubation in patients with known difficult airways.MethodsSixty‐eight adult patients, with preoperative predictors of difficult intubation, were scheduled for elective surgery under general anaesthesia. After assessing the direct laryngoscopy view, 23 patients with Cormack–Lehane III/IV were included in the study. An LMA‐SupremeTM was inserted, followed by the passage of a flexible bronchoscope loaded with an Aintree Intubation Catheter into the trachea. The bronchoscope and LMA‐SupremeTM were removed, and a tracheal tube was railroaded over the Aintree Intubation Catheter into the trachea.ResultsTracheal intubation was successful in all patients using the above technique. SpO2 was >95% during the intubation procedure.ConclusionsWe conclude that the LMA‐SupremeTM is a successful conduit for bronchoscopic/Aintree Intubation Catheter‐guided intubation in patients with known difficult airway.
Cytogenetic analysis of human cells reveals specific patterns of DNA damage in replicative and oncogene‐induced senescence
Authors: Falcone Germana , Mazzola Alessia , Michelini Flavia , Bossi Gianluca , Censi Federica , Biferi Maria G. , Minghetti Luisa , Floridia Giovanna , Federico Maurizio , Musio Antonio , Crescenzi Marco 
Published: November 2012

SummarySenescence is thought to be triggered by DNA damage, usually indirectly assessed as activation of the DNA damage response (DDR), but direct surveys of genetic damage are lacking. Here, we mitotically reactivate senescent human fibroblasts to evaluate their cytogenetic damage. We show that replicative senescence is generally characterized by telomeric fusions. However, both telomeric and extratelomeric aberrations are prevented by hTERT, indicating that even non‐telomeric damage descends from the lack of telomerase. Compared with replicative senescent cells, oncogene‐induced senescent fibroblasts display significantly higher levels of DNA damage, depicting how oncogene activation can catalyze the generation of further, potentially tumorigenic, genetic damage.
Copy number variations identified in the chicken using a 60K SNP BeadChip
Authors: Jia X. , Chen S. , Zhou H. , Li D. , Liu W. , Yang N. 
Published: November 2012

SummaryCopy number variation (CNV) is considered an important genetic variation, contributing to many economically important traits in the chicken. Although CNVs can be detected using a comparative genomic hybridization array, the high‐density SNP array has provided an alternative way to identify CNVs in the chicken. In the current study, a chicken 60K SNP BeadChip was used to identify CNVs in two distinct chicken genetic lines (White Leghorn and dwarf) using the penncnv program. A total of 209 CNV regions were identified, distributing on chromosomes 1–22 and 24–28 and encompassing 13.55 Mb (1.42%) of chicken autosomal genome area. Three of seven selected CNVs (73.2% individuals) were completely validated by quantitative PCR. To our knowledge, this is the first report in the chicken identifying CNVs using a SNP array. Identification of 190 new identified CNVs illustrates the feasibility of the chicken 60K SNP BeadChip to detect CNVs in the chicken, which lays a solid foundation for future analyses of associations of CNVs with economically important phenotypes in chickens.
Hospital‐wide breastfeeding rates vs. breastmilk provision for very‐low‐birth‐weight infants
Authors: Lee Henry C , Jegatheesan Priya , Gould Jeffrey B , A Dudley Raymond 
Published: November 2012

AbstractAimTo investigate the relationship between breastmilk feeding in very‐low‐birth‐weight infants in the neonatal intensive care unit and breastmilk feeding rates for all newborns by hospital.MethodsThis was a cross‐sectional study of 111 California hospitals in 2007 and 2008. Correlation coefficients were calculated between overall hospital breastfeeding rates and breastmilk feeding rates of very‐low‐birth‐weight infants. Hospitals were categorized in quartiles by crude and adjusted very‐low‐birth‐weight infant rates to compare rankings between measures.ResultsCorrelation between breastmilk feeding rates of very‐low‐birth‐weight infants and overall breastfeeding rates varied by neonatal intensive care unit level of care from 0.13 for intermediate hospitals to 0.48 for regional hospitals. For hospitals categorized in the top quartile according to overall breastfeeding rate, only 46% were in the top quartile for both crude and adjusted very‐low‐birth‐weight infant rates. On the other hand, when considering the lowest quartile for overall breastfeeding hospitals, three of 27 (11%) actually were performing in the top quartile of performance for very‐low‐birth‐weight infant rates.ConclusionsReporting hospital overall breastfeeding rates and neonatal intensive care unit breastmilk provision rates separately may give an incomplete picture of quality of care.
Adolescence extended: implications of new brain research on medicine and policy
Authors: Moreno Megan , Trainor Meaghan E 
Published: November 2012

AbstractLast December, the Excellence in Paediatrics conference presented a panel discussion of how new biologic findings from brain imaging cast new light on adolescent development. This study will review this presentation, focusing on the interplay between adolescent development and new brain research findings.ConclusionPaediatricians can consider these new insights in both interacting individually with patients and advocating for policies within their communities.
A phase 1 study of prasugrel in patients with sickle cell disease: pharmacokinetics and effects on ex vivo platelet reactivity
Authors: Jakubowski Joseph A. , Zhou Chunmei , Small David S. , Winters Kenneth J. , Lachno D. Richard , Frelinger Andrew L. , Howard Jo , Mant Timothy G. , Jurcevic Stipo , Payne Christopher D. 
Published: November 2012

AimsPrasugrel is a novel thienopyridine P2Y12 adenosine diphosphate (ADP) receptor antagonist that inhibits ADP‐mediated platelet activation and aggregation. Accordingly, it may be useful in reducing platelet‐related ischaemia in sickle cell disease (SCD). Exposure to prasugrel's active metabolite (Pras‐AM) and its antiplatelet activity in SCD have not been investigated.MethodsThirteen adult patients with SCD and an equal number of matched healthy control subjects were studied before and after 12 days of 5.0 or 7.5 mg day−1 prasugrel treatment. Platelet reactivity was assessed by light transmission aggregometry (LTA), impedance aggregometry (MEA), VerifyNow® P2Y12, vasodilator‐stimulated phosphoprotein (VASP) phosphorylation and Plateletworks. Exposure to Pras‐AM was also assessed.ResultsAt baseline, patients with SCD showed increased platelet reactivity vs. healthy control subjects with VerifyNow (408 vs. 323 P2Y12 reaction units (PRU), respectively, P = 0.003) and MEA (106 vs. 77 area under the aggregation curve (AU.min), P = 0.002); lower platelet reactivity index with VASP flow cytometry (59 vs. 79% platelet reactivity index (PRI), P = 0.018); and no significant differences with LTA, VASP enzyme‐linked immunosorbent assay or Plateletworks. Relative to baseline, prasugrel significantly reduced platelet reactivity by all assays in both populations (all P < 0.05). Prasugrel was well tolerated, with no bleeding‐related events in patients with SCD. The mean concentration–time profiles of Pras‐AM were comparable between healthy subjects and patients with SCD following a single 10 mg prasugrel dose and following the 12th dose of 7.5 or 5 mg prasugrel.ConclusionsResults demonstrate that in response to prasugrel, patients with SCD and healthy subjects have similar degrees of platelet inhibition and exposure to Pras‐AM, and provide a basis for further study of prasugrel in patients with SCD.
Evaluating sleep in bipolar disorder: comparison between actigraphy, polysomnography, and sleep diary
Authors: Kaplan Katherine A , Talbot Lisa S , Gruber June , Harvey Allison G 
Published: November 2012

Kaplan KA, Talbot LS, Gruber J, Harvey AG. Evaluating sleep in bipolar disorder: comparison between actigraphy, polysomnography, and sleep diary.  Bipolar Disord 2012: 14: 870–879. © 2012 John Wiley & Sons A/S.Published by Blackwell Publishing Ltd.Objectives:  Bipolar disorder is an illness characterized by sleep and circadian disturbance, and monitoring sleep in this population may signal an impending mood change. Actigraphy is an important clinical and research tool for examining sleep, but has not yet been systematically compared to polysomnography or sleep diary in bipolar disorder. The present study compares actigraphy, polysomnography, and sleep diary estimates of five standard sleep parameters in individuals with bipolar disorder and matched controls across two nights of assessment.Methods:  Twenty‐seven individuals who met diagnostic criteria for bipolar disorder type I or II and were currently between mood episodes, along with 27 matched controls with no history of psychopathology or sleep disturbance, underwent two nights of research laboratory monitoring. Sleep was estimated via polysomnography, actigraphy, and sleep diary.Results:  Over the 108 nights available for comparison, sleep parameter estimates from actigraphy and polysomnography were highly correlated and did not differ between the two groups or across the two nights for sleep onset latency, wake after sleep onset, number of awakenings, total sleep time, or sleep efficiency percentage. The medium wake threshold algorithm in the actigraphy software was the most concordant with polysomnography and diaries across the five sleep parameters. Concordance between actigraphy, polysomnography, and sleep diary was largely independent of insomnia presence and medication use.Conclusions:  Actigraphy is a valid tool for estimating sleep length and fragmentation in bipolar disorder.
Quantifying VBAC Risk: Muddying the Waters
Authors: Kotaska Andrew 
Published: November 2012

AbstractThe Landon et al and the Crowther et al papers are both prospective trials comparing planned vaginal birth after a previous cesarean section (VBAC) with elective cesarean section in women eligible for a trial of labor. With 33,000 women, the cohort studied by Landon et al in conjunction with the National Institute of Child Health and Human Development (NICHHD) spawned multiple publications, giving estimates of VBAC risks and success relevant to women in a wide variety of clinical situations. Data abstraction was careful and outcomes were hard and verified. With 2,300 women, the study by Crowther et al, was 6 percent the size of the Landon‐NICHHD study. Although it claimed “increased risk of both fetal death or liveborn infant death prior to discharge or serious infant outcome,” there were only 2 perinatal deaths—both stillbirths prior to 39 weeks' gestation and unrelated to mode of delivery. Of the 28 infants with “serious neonatal morbidity,” only three could have resulted from uterine rupture; prior experience with this outcome indicates all three will likely escape long‐term morbidity. Pseudorandomization and erroneous adherence to an intention‐to‐treat principle seriously hinder the study's internal validity, attributing outcomes for one quarter of women undergoing elective cesarean section to the planned VBAC group. The study by Landon and NICHHD is over 10 times larger and of much higher quality than the study by Crowther et al. The Landon‐NICHHD publications should be used to help women make decisions about planned mode of delivery after cesarean. (BIRTH 39:4 December 2012)
Bath salts components mephedrone and methylenedioxypyrovalerone (MDPV) act synergistically at the human dopamine transporter
Authors: Cameron Krasnodara N , Kolanos Renata , Solis Ernesto , Glennon Richard A , De Felice Louis J 
Published: November 2012

Background and PurposeBath salts is the street name for drug combinations that contain synthetic cathinone analogues, among them possibly mephedrone (MEPH) and certainly methylenedioxypyrovalerone (MDPV). In animal studies, cathinone and certain cathinone analogues release dopamine (DA), similar to the action of amphetamine (AMPH) and methamphetamine (METH). AMPH and METH act on the human DA transporter (hDAT); thus, we investigated MEPH and MDPV acting at hDAT.Experimental ApproachWe recorded electrical currents mediated by hDAT expressed in Xenopus laevis oocytes and exposed to: DA, METH, a known hDAT stimulant and DA releaser, MEPH, MDPV, MEPH + MDPV, or cocaine, a known hDAT inhibitor.Key ResultsDA, METH and MEPH induce an inward current (depolarizing) when the oocyte is held near the resting potential (–60 mV), therefore acting as excitatory hDAT substrates. Structurally analogous MDPV induces an outward (hyperpolarizing) current similar to cocaine, therefore acting as an inhibitory non‐substrate blocker.Conclusions and ImplicationsTwo components of bath salts, MEPH and MDPV, produce opposite effects at hDAT that are comparable with METH and cocaine, respectively. In our assay, MEPH is nearly as potent as METH; however, MDPV is much more potent than cocaine and its effect is longer lasting. When applied in combination, MEPH exhibits faster kinetics than MDPV, viz., the MEPH depolarizing current occurs seconds before the slower MDPV hyperpolarizing current. Bath salts containing MEPH (or a similar drug) and MDPV might then be expected initially to release DA and subsequently prevent its reuptake via hDAT. Such combined action possibly underlies some of the reported effects of bath salts abuse.