bluuebunny/crossref_metadata_2025 huggingface dataset:
Integration of Hedgehog and BMP signalling by the engrailed2a gene in the zebrafish myotome
Authors: Maurya Ashish K. , Tan Haihan , Souren Marcel , Wang Xingang , Wittbrodt Joachim , Ingham Philip W.
Published: January 2011

Different levels and timing of Hedgehog (Hh) signalling activity have been proposed to specify three distinct cell types in the zebrafish myotome. Two of these, the medial fast-twitch fibres (MFFs) and the slow-twitch muscle pioneers (MPs) are characterised by expression of eng1a, -1b and -2a and require the highest levels of Hh for their specification. We have defined a minimal eng2a element sufficient to drive reporter expression specifically in MPs and MFFs. This element binds both Gli2a, a mediator of Hh signalling, and activated Smads (pSmads), mediators of bone morphogenic protein (BMP) signalling, in vivo. We found a strict negative correlation between nuclear accumulation of pSmad, and eng2a expression in myotomal cells and show that abrogation of pSmad accumulation results in activation of eng2a, even when Hh signalling is attenuated. Conversely, driving nuclear accumulation of pSmad suppresses the induction of eng expression even when Hh pathway activity is maximal. Nuclear accumulation of pSmads is depleted by maximal Hh pathway activation. We show that a synthetic form of the Gli2 repressor interacts with Smad1 specifically in the nuclei of myotomal cells in the developing embryo and that this interaction depends upon BMP signalling activity. Our results demonstrate that the eng2a promoter integrates repressive and activating signals from the BMP and Hh pathways, respectively, to limit its expression to MPs and MFFs. We suggest a novel basis for crosstalk between the Hh and BMP pathways, whereby BMP-mediated repression of Hh target genes is promoted by a direct interaction between Smads and truncated Glis, an interaction that is abrogated by Hh induced depletion of the latter.
An urgent necessity under general anaesthesia – surgical gloves made into re-breathing bag
Authors: Oyinpreye Jasper Abiodun , Ofejiro Okperi Blessing , Osemwegie Osaguona Anthony
Published: January 2011

Anaesthetic practice in resource-poor countries often requires a lot of improvisation on the part of practitioners in order to meet the needs of patients. Disposables in a low-resource environment are usually stretched beyond the manufacturer's recommended life span. While anaesthetizing a six-month-old baby with cleft lip, the reservoir bag was accidentally torn and was replaced with latex surgical gloves. In the absence of a spare bag this replacement served the patient throughout the period of surgery.
Clubfoot in Malawi: local theories of causation
Authors: Bedford K Juliet A , Chidothi Paul , Sakala Harris , Cashman John , Lavy Chris
Published: January 2011

This paper examines local theories of the causation of clubfoot expressed by the guardians of children undergoing treatment at clinics run by the Malawi National Clubfoot Programme (MNCP). Core data was collected and analysed using qualitative methodologies of critical medical anthropology. Sixty detailed case studies were completed, each based on an extended open-ended interview with patient guardians. Five main theories of causation were put forward: God; the devil; witchcraft or curses; biological reasons; and inherited condition. Each was elaborated in a variety of ways. There is growing international recognition of the importance of examining the relationship between culture and disability. This study is the first attempt to do so for clubfoot in Malawi. It provides a platform on which to build future qualitative research that can be harnessed by the MNCP and similar initiatives to develop their knowledge base and service provision, both in Malawi and the wider African context.
Cardiotoxicity from ‘safe’ herbomineral formulations
Authors: Dwivedi Shridhar , Aggarwal Amitesh , Sharma Vishal
Published: January 2011

Many herbomineral preparations are currently being used as therapeutic remedies for common ailments. Commonly known cardiotoxic herbs are Aconitum ferox (aconite), Areca catechu (betel nut), Thevetia peruviana (yellow oleander) and Cleistanus collinus (oduvan). Herbs mixed with lead, copper and/or mercury are known to be highly toxic. They produce cardiac arrhythmias, mainly ventricular ectopics, ventricular tachycardia and various degrees of arterioventricular (AV) blocks. We report 12 such successive cases where the patients developed vague feelings of discomfort, dizziness, chest discomfort and ventricular arrhythmias following herbal drug ingestion which warranted the immediate discontinuation of the drug. Three of the patients died. This paper emphasizes the risk of unsupervised use of herbomineral preparations by patients who believe that the remedies are always ‘safe’ and the urgent necessity for the pharmacognostic identification of the constituent herbs, their toxicological studies, uniform nomenclature, authenticity and standardization of plants and their parts before advocating them for therapeutic use.
Specific requirement of DRB4, a dsRNA-binding protein, for the in vitro dsRNA-cleaving activity of Arabidopsis Dicer-like 4
Authors: Fukudome Akihito , Kanaya Akihiro , Egami Mai , Nakazawa Yukihiro , Hiraguri Akihiro , Moriyama Hiromitsu , Fukuhara Toshiyuki
Published: January 2011

Arabidopsis thaliana Dicer-like 4 (DCL4) produces 21-nt small interfering RNAs from both endogenous and exogenous double-stranded RNAs (dsRNAs), and it interacts with DRB4, a dsRNA-binding protein, in vivo and in vitro. However, the role of DRB4 in DCL4 activity remains unclear because the dsRNA-cleaving activity of DCL4 has not been characterized biochemically. In this study, we biochemically characterize DCL4's Dicer activity and establish that DRB4 is required for this activity in vitro. Crude extracts from Arabidopsis seedlings cleave long dsRNAs into 21-nt small RNAs in a DCL4/DRB4-dependent manner. Immunoaffinity-purified DCL4 complexes produce 21-nt small RNAs from long dsRNA, and these complexes have biochemical properties similar to those of known Dicer family proteins. The DCL4 complexes purified from drb4-1 do not cleave dsRNA, and the addition of recombinant DRB4 to drb4-1 complexes specifically recovers the 21-nt small RNA generation. These results reveal that DCL4 requires DRB4 to cleave long dsRNA into 21-nt small RNAs in vitro. Amino acid substitutions in conserved dsRNA-binding domains (dsRBDs) of DRB4 impair three activities: binding to dsRNA, interacting with DCL4, and facilitating DCL4 activity. These observations indicate that the dsRBDs are critical for DRB4 function. Our biochemical approach and observations clearly show that DRB4 is specifically required for DCL4 activity in vitro.
Theta-Burst Transcranial Magnetic Stimulation Alters Cortical Inhibition
Authors: Benali Alia , Trippe Jörn , Weiler Elke , Mix Annika , Petrasch-Parwez Elisabeth , Girzalsky Wolfgang , Eysel Ulf T. , Erdmann Ralf , Funke Klaus
Published: January 2011

Human cortical excitability can be modified by repetitive transcranial magnetic stimulation (rTMS), but the cellular mechanisms are largely unknown. Here, we show that the pattern of delivery of theta-burst stimulation (TBS) (continuous versus intermittent) differently modifies electric activity and protein expression in the rat neocortex. Intermittent TBS (iTBS), but not continuous TBS (cTBS), enhanced spontaneous neuronal firing and EEG gamma band power. Sensory evoked cortical inhibition increased only after iTBS, although both TBS protocols increased the first sensory response arising from the resting cortical state. Changes in the cortical expression of the calcium-binding proteins parvalbumin (PV) and calbindin D-28k (CB) indicate that changes in spontaneous and evoked cortical activity following rTMS are in part related to altered activity of inhibitory systems. By reducing PV expression in the fast-spiking interneurons, iTBS primarily affected the inhibitory control of pyramidal cell output activity, while cTBS, by reducing CB expression, more likely affected the dendritic integration of synaptic inputs controlled by other classes of inhibitory interneurons. Calretinin, the third major calcium-binding protein expressed by another class of interneurons was not affected at all. We conclude that different patterns of TBS modulate the activity of inhibitory cell classes differently, probably depending on the synaptic connectivity and the preferred discharge pattern of these inhibitory neurons.
Thalamic Ryanodine Receptors Are Involved in Controlling the Tonic Firing of Thalamocortical Neurons and Inflammatory Pain Signal Processing
Authors: Cheong Eunji , Kim Chanki , Choi B. Jiwon , Sun Minjeong , Shin Hee-Sup
Published: January 2011

Ryanodine receptors (RyRs) are highly conductive intracellular Ca2+release channels which are widely expressed in the CNS. They rapidly increase the intracellular Ca2+concentrations in neuronal cells in response to Ca2+influx through voltage-gated Ca2+channels. A previous study reported that RyRs were expressed in thalamocortical (TC) neurons, but their physiological function has remained elusive. Here, we show that the activation of RyRs in TC neurons in mice decreases their tonic firing rate while blocking them induces the opposite response. Furthermore, activation of RyRs in ventroposteriomedial/ventroposteriolateral nuclei reduces the behavioral responses to inflammatory pain and blocking them increases the responses. This study highlights the importance of the intracellular Ca2+release via RyRs in controlling the excitability of TC neurons and in inflammatory pain signal processing in the thalamus.
Regulation of Synapse Structure and Function by Distinct Myosin II Motors
Authors: Rubio Maria D. , Johnson Richard , Miller Courtney A. , Huganir Richard L. , Rumbaugh Gavin
Published: January 2011

Ongoing synaptic function and rapid, bidirectional plasticity are both controlled by regulatory mechanisms within dendritic spines. Spine actin dynamics maintain synapse structure and function, and cytoskeletal rearrangements in these structures trigger structural and functional plasticity. Therefore, proteins that interact with actin filaments are attractive candidates to regulate synaptic actin dynamics and, thus, synapse structure and function. Here, we have cloned the rat isoform of class II myosin heavy chainMyH7Bin brain. Unexpectedly, this isoform resembles muscle-type myosin II rather than the ubiquitously expressed nonmuscle myosin II isoforms, suggesting that a rich functional diversity of myosin II motors may exist in neurons. Indeed, reducing the expression ofMyH7Bin mature neurons caused profound alterations to dendritic spine structure and excitatory synaptic strength. Structurally, dendritic spines had large, irregularly shaped heads that contained many filopodia-like protrusions. Neurons with reducedMyH7Bexpression also had impaired miniature EPSC amplitudes accompanied by a decrease in synaptic AMPA receptors, which was linked to alterations of the actin cytoskeleton.MyH7B-mediated control over spine morphology and synaptic strength was distinct from that of a nonmuscle myosin, myosin IIb. Interestingly, when myosin IIb expression andMyH7Bexpression were simultaneously knocked-down in neurons, a third, more pronounced phenotype emerged. Together, our data provide evidence that distinct myosin II isoforms work together to regulate synapse structure and function in cultured hippocampal neurons. Thus, myosin II motor activity is emerging as a broad regulatory mechanism for control over complex actin networks within dendritic spines.
Disentangling Scene Content from Spatial Boundary: Complementary Roles for the Parahippocampal Place Area and Lateral Occipital Complex in Representing Real-World Scenes
Authors: Park Soojin , Brady Timothy F. , Greene Michelle R. , Oliva Aude
Published: January 2011

Behavioral and computational studies suggest that visual scene analysis rapidly produces a rich description of both the objects and the spatial layout of surfaces in a scene. However, there is still a large gap in our understanding of how the human brain accomplishes these diverse functions of scene understanding. Here we probe the nature of real-world scene representations using multivoxel functional magnetic resonance imaging pattern analysis. We show that natural scenes are analyzed in a distributed and complementary manner by the parahippocampal place area (PPA) and the lateral occipital complex (LOC) in particular, as well as other regions in the ventral stream. Specifically, we study the classification performance of different scene-selective regions using images that vary in spatial boundary and naturalness content. We discover that, whereas both the PPA and LOC can accurately classify scenes, they make different errors: the PPA more often confuses scenes that have the same spatial boundaries, whereas the LOC more often confuses scenes that have the same content. By demonstrating that visual scene analysis recruits distinct and complementary high-level representations, our results testify to distinct neural pathways for representing the spatial boundaries and content of a visual scene.
Spatiotemporal Evolution of the Functional Magnetic Resonance Imaging Response to Ultrashort Stimuli
Authors: Hirano Yoshiyuki , Stefanovic Bojana , Silva Afonso C.
Published: January 2011

The specificity of the hemodynamic response function (HRF) is determined spatially by the vascular architecture and temporally by the evolution of hemodynamic changes. The stimulus duration has additional influence on the spatiotemporal evolution of the HRF, as brief stimuli elicit responses that engage only the local vasculature, whereas long stimuli lead to the involvement of remote vascular supply and drainage. Here, we used functional magnetic resonance imaging to investigate the spatiotemporal evolution of the blood oxygenation level-dependent (BOLD), cerebral blood flow (CBF), and cerebral blood volume (CBV) HRF to ultrashort forelimb stimulation in an anesthetized rodent model. The HRFs to a single 333-μs-long stimulus were robustly detected and consisted of a rapid response in both CBF and CBV, with an onset time (OT) of 350 ms and a full width at half-maximum of 1 s. In contrast, longer stimuli elicited a dispersive transit of oxygenated blood across the cortical microvasculature that significantly prolonged the evolution of the CBV HRF, but not the CBF. The CBF and CBV OTs suggest that vasoactive messengers are synthesized, released, and effective within 350 ms. However, the difference between the BOLD and CBV OT (∼100 ms) was significantly smaller than the arteriolar–venular transit time (∼500 ms), indicating an arterial contribution to the BOLD HRF. Finally, the rapid rate of growth of the active region with stimulus elongation suggests that functional hyperemia is an integrative process that involves the entire functional cortical depth. These findings offer a new view into the spatiotemporal dynamics of functional hemodynamic regulation in the brain.
Neural Characterization of the Speed–Accuracy Tradeoff in a Perceptual Decision-Making Task
Authors: Wenzlaff Hermine , Bauer Markus , Maess Burkhard , Heekeren Hauke R.
Published: January 2011

Decisions often necessitate a tradeoff between speed and accuracy (SAT), that is, fast decisions are more error prone while careful decisions take longer. Sequential sampling models assume that evidence for different response alternatives is accumulated over time and suggest that SAT modulates the decision system by setting a lower threshold (boundary) on required accumulated evidence to commit a response under time pressure. We investigated how such a speed accuracy tradeoff is implemented neurally under different levels of sensory evidence. Using magnetoencephalography (MEG) and a face-house categorization task, we show that the later decision- and motor-related systems rather than the early sensory system are modulated by SAT. Source analysis revealed that the bilateral supplementary motor areas (SMAs) and the medial precuneus were more activated under the speed instruction and correlated negatively (right SMA) with the boundary parameter, whereas the left dorsolateral prefrontal cortex (DLPFC) was more activated under the accuracy instruction and showed a positive correlation with the boundary. The findings are interpreted in the sense that SMA activity dynamically facilitates fast responses during stimulus processing, potentially by disinhibiting thalamo-striatal loops, whereas DLPFC reflects accumulated evidence before response execution.
Early Maturation of the Linguistic Dorsal Pathway in Human Infants
Authors: Leroy François , Glasel Hervé , Dubois Jessica , Hertz-Pannier Lucie , Thirion Bertrand , Mangin Jean-François , Dehaene-Lambertz Ghislaine
Published: January 2011

Human infants, unlike even closely related primates, exhibit a remarkable capacity for language learning. Yet how the underlying anatomical network matures remains largely unknown. The classical view is that of a largely immature brain comprising only a few islands of maturity in primary cortices. This view has favored a description of learning based on bottom-up algorithms and has tended to discard the role of frontal regions, which were assumed to be barely functional early on. Here, using an index based on the normalized T2-weighted magnetic resonance signal, we have quantified maturation within the linguistic network in fourteen 1- to 4-month-old infants. Our results show first that the ventral superior temporal sulcus (STS), and not the inferior frontal area, is the less mature perisylvian region. A significant difference of maturation in the STS favoring the right side is an early testimony of the distinctive left–right development of this structure observed during the whole life. Second, asymmetries of maturation in Broca's area were correlated with asymmetries in the posterior STS and in the parietal segment of the arcuate fasciculus, suggesting that an efficient frontotemporal dorsal pathway might provide infants with a phonological loop circuitry much earlier than expected.
Reduced Neuronal Inhibition and Coordination of Adolescent Prefrontal Cortex during Motivated Behavior
Authors: Sturman David A. , Moghaddam Bita
Published: January 2011

Adolescence is a time of both cognitive maturation and vulnerability to several major psychiatric illnesses and drug dependence. There is increasing awareness that behavioral or pharmacological intervention during this period may be critical for disease prevention in susceptible individuals. Therefore, we must attain a deeper understanding of how the adolescent brain processes salient events relevant to motivated behavior. To do this, we recorded single-unit and local field potential activity in the orbitofrontal cortex of rats as they performed a simple reward-driven operant task. Adolescents encoded basic elements of the task differently than adults, indicating that neuronal processing of salient events differs in the two age groups. Entrainment of local field potential oscillations, variance in spike timing, and relative proportions of inhibitory and excitatory responses differed in an event-specific manner. Overall adolescent phasic neural activity was less inhibited and more variable through much of the task. Cortical inhibition is essential for efficient communication between neuronal groups, and reduced inhibitory control of cortical activity has been implicated in schizophrenia and other disorders. Thus, these results suggest that reduced inhibitory responses of adolescent cortical neurons to salient events could be a critical mechanism for some of the increased vulnerabilities of this period.
Errors and Conflict at the Task Level and the Response Level
Authors: Desmet Charlotte , Fias Wim , Hartstra Egbert , Brass Marcel
Published: January 2011

In the last decade, research on error and conflict processing has become one of the most influential research areas in the domain of cognitive control. There is now converging evidence that a specific part of the posterior frontomedian cortex (pFMC), the rostral cingulate zone (RCZ), is crucially involved in the processing of errors and conflict. However, error-related research has focused primarily on a specific error type, namely, response errors. The aim of the present study was to investigate whether errors on the task level rely on the same neural and functional mechanisms. Here we report a dissociation of both error types in the pFMC: whereas response errors activate the RCZ, task errors activate the dorsal frontomedian cortex. Although this last region shows an overlap in activation for task and response errors on the group level, a closer inspection of the single-subject data is more in accordance with a functional anatomical dissociation. When investigating brain areas related to conflict on the task and response levels, a clear dissociation was perceived between areas associated with response conflict and with task conflict. Overall, our data support a dissociation between response and task levels of processing in the pFMC. In addition, we provide additional evidence for a dissociation between conflict and errors both at the response level and at the task level.
AKAP79/150 Impacts Intrinsic Excitability of Hippocampal Neurons through Phospho-Regulation of A-type K+Channel Trafficking
Authors: Lin Lin , Sun Wei , Kung Faith , Dell'Acqua Mark L. , Hoffman Dax A.
Published: January 2011

Kv4.2, as the primary α-subunit of rapidly inactivating, A-type voltage-gated K+(Kv) channels expressed in hippocampal CA1 pyramidal dendrites, plays a critical role in regulating their excitability. Activity-dependent trafficking of Kv4.2 relies on C-terminal protein kinase A (PKA) phosphorylation. A-kinase-anchoring proteins (AKAPs) target PKA to glutamate receptor and ion channel complexes to allow for discrete, local signaling. As part of a previous study, we showed that AKAP79/150 interacts with Kv4.2 complexes and that the two proteins colocalize in hippocampal neurons. However, the nature and functional consequence of their interaction has not been previously explored. Here, we report that the C-terminal domain of Kv4.2 interacts with an internal region of AKAP79/150 that overlaps with its MAGUK (membrane-associated guanylate kinase)-binding domain. We show that AKAP79/150-anchored PKA activity controls Kv4.2 surface expression in heterologous cells and hippocampal neurons. Consistent with these findings, disrupting PKA anchoring led to a decrease in neuronal excitability, while preventing dephosphorylation by the phosphatase calcineurin resulted in increased excitability. These results demonstrate that AKAP79/150 provides a platform for dynamic PKA regulation of Kv4.2 expression, fundamentally impacting CA1 excitability.
Parametrischer Entwurf dynamischer Ausgangsrückführungen für reguläre Deskriptorsysteme
Authors: Manderla Maximilian , Konigorski Ulrich
Published: January 2011

Der Beitrag beschreibt ein neues Verfahren zur Synthese konstanter statischer und dynamischer Ausgangsrückführungen für reguläre lineare zeitinvariante Deskriptorsysteme. Neben der Vorgabe der Regelungseigenwerte und der Sicherstellung der Regularität des geschlossenen Regelkreises können sämtliche Entwurfsfreiheitsgrade und deren Auswirkung auf die Dynamik des geschlossenen Regelkreises in expliziter Form angegeben werden. Der Entwurf erfolgt durch die Aufspaltung des Problems in zwei duale Teilprobleme. Vollständige Steuer- und Beobachtbarkeit werden nicht gefordert.
Preparation and evaluation of hydrous titanium oxide as a high affinity adsorbent for molybdenum (99Mo) and its potential for use in 99mTc generators
Authors: Qazi Q. M. , Ahmad Mushtaq
Published: January 2011

Hydrous titanium oxide was prepared and its affinity as an adsorbent for molybdenum ( 99Mo) and its potential for use in 99mTc generators were evaluated. Adsorption behavior of molybdate on hydrous titanium oxide was studied at boiling water bath temperature (∼100 °C) using radiotracer technique. Various parameters affecting the adsorption of molybdenum, such as pH, amount of molybdenum, incubation period etc. , were determined. Technetium-99m generators were prepared by adsorbing low specific activity Molybdenum-99 (∼230 mg) on 1 g hydrous titanium oxide. Elutions were carried out with normal saline. Performance of the generators, such as 99Mo breakthrough, titanium content, pH, elution profile, radiochemical purity and labeling efficiency of kits, was checked.
Separation of lanthanides and actinides on a bistriazinyl pyridine coated reverse phase column
Authors: Deepika P. , Sivaraman N. , Sabharwal K. N. , Srinivasan T. G. , Vasudeva Rao P. R.
Published: January 2011

The retention behaviour of uranium, thorium, americium and lanthanides has been investigated, using a reverse phase C18 column modified with 2,6-bis(5,6-dipropyl-1,2,4-triazin-3-yl)pyridine (n-Pr-BTP) with the aim of investigating rapid lanthanide-actinide separations by HPLC technique. Nitric acid and α-hydroxy isobutyric acid (α-HIBA) have been employed as the mobile phase. The influence of mobile phase pH and concentration on the retention of metal ions has been studied. The aim of this study is to investigate the use of BTP coated reverse phase columns as analytical columns for the fast separation of the minor actinides from the lanthanides in the high-level waste (HLW), and to explore whether such columns can be used on a preparative scale for the purification and the recovery of minor actinides from the high-level waste (HLW). It was observed that reverse phase columns modified with BTP showed greater affinity for actinides but exhibited no retention for lanthanides and the lanthanide-actinide separations could be achieved in nitric acid mobile phase, without the need for complexing agents. Americium was separated from the lanthanides with good peak profile and baseline resolution in both nitric acid as well as α-HIBA as the mobile phase. Based on this, the separation of americium from the lanthanides in the HLW was also demonstrated. The retention of a significant amount of thorium by the column in breakthrough studies also indicated that these columns can be used for preparative scale purification of the actinides.
Konformitätsrisiken bei der Messung der Maschenweiten von Drahtgewebe- und Drahtgitterprodukten
Authors: Hinrichs Wilfried
Published: January 2011

In einem Forschungsprojekt wurde durch eine Analyse von Herstellungs- und Messdaten aus der Produktion von Drahtgeweben und Drahtgittern festgestellt, dass die Maschenweiten in Kettrichtung eher beta- als normalverteilt sind. Diese Erkenntnis kann einen signifikanten Einfluss auf die Konformitätsbewertung haben, weil davon sowohl die Konformitätswahrscheinlichkeiten als auch die Anbieter- und Abnehmerrisiken betroffen sind. In Modellrechnungen hat sich gezeigt, dass diese Werte in den praxisrelevanten Bereichen deutlich geringer sind, als bei der Annahme von Normalverteilungen. Dieser Vorteil wird allerdings dadurch relativiert, dass es höherer Aufwendungen für Messungen bedarf, um solide und produktspezifische Kennwerte für die Betaverteilung zu erzeugen.
Messung dynamischer Deformationen und Schwingungen schnell drehender Rotoren
Authors: Pfister Thorsten , Günther Philipp , Dreier Florian , Czarske Jürgen
Published: January 2011

Zur Steigerung der Betriebssicherheit und der Energieeffizienz von Motoren und Turbomaschinen ist die genaue Kenntnis des dynamischen Verhaltens des Rotors im Betrieb erforderlich. Dies ist eine große Herausforderung für die Messtechnik, da die Form der schnell bewegten rauen Objektoberfläche mit Mikrosekunden Zeitauflösung und gleichzeitig mit Mikrometerpräzision erfasst werden muss. In diesem Beitrag wird dargestellt, wie diese anspruchsvolle Messaufgabe mit einem nicht-inkrementellen Laser-Doppler-Distanzsensor, der eine geschwindigkeitsunabhängige Messunsicherheit bietet, gelöst werden kann.
Aldosterone- and cortisol-co-secreting adrenal tumors: the lost subtype of primary aldosteronism
Authors: Späth Martin , Korovkin Svetlana , Antke Christiane , Anlauf Martin , Willenberg Holger S
Published: January 2011

Current guidelines suggest proving angiotensin-independent aldosterone secretion in patients with primary aldosteronism (PA). It is further recommended to demonstrate unilateral disease because of its consequence for therapy. A general screening for excess secretion of other hormones is not recommended. However, clinically relevant autonomous aldosterone production rarely originates in adrenal tumors, compromised of zona glomerulosa cells only. This article reviews published data on aldosterone- and cortisol-co-secreting tumors and shows that pre-operative diagnosis of such a lesion is beneficial for patients. Overt or subclinical glucocorticoid hypersecretion may interfere with diagnostic studies, e.g. adrenal venous sampling, screening of familial forms of PA on the basis of serum 18-hydroxy-cortisol (18-OH-F) determination, and provoke glucocorticoid deficiency after surgical removal of the tumor. In addition, knowledge from histological and molecular studies in patients with aldosterone- and cortisol-co-secreting tumors challenges some concepts of the development of adrenal autonomy. The presence of an aldosterone- and cortisol-co-secreting adrenocortical tumor should be considered if a patient has i) PA and an adenoma that is larger than 2.5 cm, ii) cortisol that is non-suppressible with overnight low-dose dexamethasone, or iii) grossly elevated serum levels of hybrid steroids, such as 18-OH-F.
Post-HAART Outcomes in Pediatric Populations: Comparison of Resource-Limited and Developed Countries
Authors: Peacock-Villada Elizabeth , Richardson Barbra A. , John-Stewart Grace C.
Published: January 2011

CONTEXT:

No formal comparison has been made between the pediatric post–highly active antiretroviral therapy (HAART) outcomes of resource-limited and developed countries.

OBJECTIVE:

To systematically quantify and compare major baseline characteristics and clinical end points after HAART between resource-limited and developed settings.

METHODS:

Published articles and abstracts (International AIDS Society 2009, Conference on Retroviruses and Opportunistic Infections 2010) were examined from inception (first available publication for each search engine) to March 2010. Publications that contained data on post-HAART mortality, weight-for-age z score (WAZ), CD4 count, or viral load (VL) changes in pediatric populations were reviewed. Selected studies met the following criteria: (1) patients were younger than 21 years; (2) HAART was given (≥3 antiretroviral medications); and (3) there were >20 patients. Data were extracted for baseline age, CD4 count, VL, WAZ, and mortality, CD4 and virologic suppression over time. Studies were categorized as having been performed in a resource-limited country (RLC) or developed country (DC) on the basis of the United Nations designation. Mean percentage of deaths per cohort and deaths per 100 child-years, baseline CD4 count, VL, WAZ, and age were calculated for RLCs and DCs and compared by using independent samples t tests.

RESULTS:

Forty RLC and 28 DC publications were selected (N = 17 875 RLCs; N = 1835 DC). Mean percentage of deaths per cohort and mean deaths per 100 child-years after HAART were significantly higher in RLCs than DCs (7.6 vs 1.6, P < .001, and 8.0 vs 0.9, P < .001, respectively). Mean baseline CD4% was 12% in RLCs and 23% in DCs (P = .01). Mean baseline VLs were 5.5 vs 4.7 log10 copies per mL in RLCs versus DCs (P < .001).

CONCLUSIONS:

Baseline CD4% and VL differ markedly between DCs and RLCs, as does mortality after pediatric HAART. Earlier diagnosis and treatment of pediatric HIV in RLCs would be expected to result in better HAART outcomes.
Hearing Screening in a Well-Infant Nursery: Profile of Automated ABR-Fail/OAE-Pass
Authors: Berg Abbey L. , Prieve Beth A. , Serpanos Yula C. , Wheaton Melissa A.
Published: January 2011

OBJECTIVES:

The goals were to examine the prevalence of a screening outcome pattern of auditory brainstem response fail/otoacoustic emission pass (ABR-F/OAE-P) in a cohort of infants in well-infant nurseries (WINs), to profile children at risk for auditory neuropathy spectrum disorder, and to compare inpatient costs for 2 screening protocols using automated auditory brainstem response (ABR) and otoacoustic emission (OAE) screening.

METHODS:

A total of 10.6% (n = 2167) of 20 529 infants admitted to WINs in 2006–2009 were screened for auditory neuropathy spectrum disorder risk by using an experimental protocol (automated ABR testing first, followed by OAE testing if the automated ABR test was not passed). A second WIN cohort (n = 281) was screened by using the standard WIN protocol for the facility (OAE testing first, followed by automated ABR testing if the OAE test was not passed). Comparisons were made regarding preparation and testing times and personnel costs.

RESULTS:

The ABR-F/OAE-P outcome was found for 0.92% of infants in WINs in inpatient testing and none in outpatient rescreening. The time for test preparation was 4 times longer and that for test administration was 2.6 times longer for the experimental protocol, compared with the standard protocol. Inpatient costs for the experimental protocol included 3 times greater personnel time costs.

CONCLUSIONS:

Less than 1% of infants in WINs had ABR-F/OAE-P screening outcomes as inpatients and none as outpatients. These results suggest that prevalence is low for infants cared for in WINs and use of OAE testing as a screening tool in WINs is not unreasonable.
Noninvasive Ventilation for Respiratory Distress Syndrome: A Randomized Controlled Trial
Authors: Meneses Jucille , Bhandari Vineet , Guilherme Alves Joao , Herrmann Delia
Published: January 2011

CONTEXT:

Strategies for reducing exposure to endotracheal ventilation through the use of early noninvasive ventilation has proven to be safe and effective, but the option with the greatest benefits needs to be determined.

OBJECTIVE:

To determine, in infants with respiratory distress syndrome, if early nasal intermittent positive-pressure ventilation (NIPPV) compared with nasal continuous positive airway pressure (NCPAP) decreases the need for mechanical ventilation.

PATIENTS AND METHODS:

In this single-center, randomized controlled trial, infants (gestational ages 26 to 3367 weeks) with respiratory distress syndrome were randomly assigned to receive early NIPPV or NCPAP. Surfactant was administered as rescue therapy. The primary outcome was the need for mechanical ventilation within the first 72 hours of life.

RESULTS:

A total of 200 infants, 100 in each arm, were randomly assigned. Rates of the primary outcome did not differ significantly between the NIPPV (25%) and NCPAP (34%) groups (relative risk [RR]: 0.71 [95% confidence interval (CI): 0.48–1.14]). In posthoc analysis, from 24 to 72 hours of life, significantly more infants in the NIPPV group remained extubated compared with those in the NCPAP groups (10 vs 22%; RR: 0.45 [95% CI: 0.22–0.91]). This difference was also noted in the group of infants who received surfactant therapy, NIPPV (10.9%), and NCPAP (27.1%) (RR: 0.40 [95% CI: 0.18–0.86]).

CONCLUSIONS:

Early NIPPV did not decrease the need for mechanical ventilation compared with NCPAP, overall, in the first 72 hours of life. However, further studies to assess the potential benefits of noninvasive ventilation are warranted, especially for the most vulnerable or preterm infants.
Chlamydia Screening Among Young Women: Individual- and Provider-Level Differences in Testing
Authors: Wiehe Sarah E. , Rosenman Marc B. , Wang Jane , Katz Barry P. , Fortenberry J. Dennis
Published: January 2011

OBJECTIVE:

We assessed differences in chlamydia screening rates according to race/ethnicity, insurance status, age, and previous sexually transmitted infection (STI) or pregnancy.

METHODS:

A retrospective cohort study was performed using electronic medical record and billing data for women 14 to 25 years of age in 2002–2007, assessing differences in the odds of a chlamydia test being performed at that visit.

RESULTS:

Adjusted odds of a chlamydia test being performed were lower among women 14 to 15 years of age (odds ratio: 0.83 [95% confidence interval: 0.70–1.00]) and 20 to 25 years of age (20–21 years, odds ratio: 0.78 [95% confidence interval: 0.70–0.89]; 22–23 years, odds ratio: 0.76 [95% confidence interval: 0.67–0.87]; 24–25 years, odds ratio: 0.64 [95% confidence interval: 0.57–0.73]), compared with women 18 to 19 years of age. Black women had 3 times increased odds (odds ratio: 2.96 [95% confidence interval: 2.66–3.28]) and Hispanic women nearly 13 times increased odds (odds ratio: 12.89 [95% confidence interval: 10.85–15.30]) of testing, compared with white women. Women with public (odds ratio: 1.74 [95% confidence interval: 1.58–1.91]) and public pending (odds ratio: 6.85 [95% confidence interval: 5.13–9.15]) insurance had increased odds of testing, compared with women with private insurance. After first STI diagnosis, differences according to race/ethnicity persisted but were smaller; after first pregnancy, differences persisted.

CONCLUSIONS:

Despite recommendations to screen all sexually active young women for chlamydia, providers screened women differently according to age, race/ethnicity, and insurance status, although differences were reduced after first STI or pregnancy.
Effects of Recombinant Human Prolactin on Breast Milk Composition
Authors: Powe Camille E. , Puopolo Karen M. , Newburg David S. , Lönnerdal Bo , Chen Ceng , Allen Maureen , Merewood Anne , Worden Susan , Welt Corrine K.
Published: January 2011

OBJECTIVE:

The objective of this study was to determine the impact of recombinant human prolactin (r-hPRL) on the nutritional and immunologic composition of breast milk.

METHODS:

We conducted 2 trials of r-hPRL treatment. In the first study, mothers with documented prolactin deficiency were given r-hPRL every 12 hours in a 28-day, open-label trial. In the second study, mothers with lactation insufficiency that developed while they were pumping breast milk for their preterm infants were given r-hPRL daily in a 7-day, double-blind, placebo-controlled trial. Breast milk characteristics were compared before and during 7 days of treatment.

RESULTS:

Among subjects treated with r-hPRL (N = 11), milk volumes (73 ± 36 to 146 ± 54 mL/day; P < .001) and milk lactose levels (155 ± 15 to 184 ± 8 mmol/L; P = .01) increased, whereas milk sodium levels decreased (12.1 ± 2.0 to 8.3 ± 0.5 mmol/L; P = .02). Milk calcium levels increased in subjects treated with r-hPRL twice daily (2.8 ± 0.6 to 5.0 ± 0.9 mmol/L; P = .03). Total neutral (1.5 ± 0.3 to 2.5 ± 0.4 g/L; P = .04) and acidic (33 ± 4 to 60 ± 6 mg/L; P = .02) oligosaccharide levels increased in r-hPRL-treated subjects, whereas total daily milk immunoglobulin A secretionwas unchanged.

CONCLUSIONS:

r-hPRL treatment increased milk volume and induced changes in milk composition similar to those that occur during normal lactogenesis. r-hPRL also increased antimicrobially active oligosaccharide concentrations. These effects were achieved for women with both prolactin deficiency and lactation insufficiency.
Impact of Rotavirus Vaccination on Hospital-Acquired Rotavirus Gastroenteritis in Children
Authors: Anderson Evan J. , Rupp Angela , Shulman Stanford T. , Wang Deli , Zheng Xiaotian , Noskin Gary A.
Published: January 2011

OBJECTIVE:

Data show that after the implementation of routine rotavirus vaccination for infants in the United States, community-acquired (CA) rotavirus cases declined substantially in the 2007–2008 season. The impact of community-based rotavirus vaccination on the substantial burden of hospital-acquired (HA) rotavirus has not been documented.

PATIENTS AND METHODS:

We assessed CA and HA rotavirus, respiratory syncytial virus, and influenza infections at Children's Memorial Hospital for 5 winter seasons (defined as occurring from September through May) from 2003 to 2008. We also report rotavirus data from the 2008–2009 season.

RESULTS:

A similar dramatic decline (>60% compared with the median of previous seasons) occurred in the rates of cases of both CA (P < .0001) rotavirus hospitalizations and HA (P < .01) rotavirus infections in the 2007–2008 season compared with previous seasons, whereas the rates of CA and HA influenza and respiratory syncytial virus, respectively, remained stable. Improvements in hand-hygiene compliance did not correlate with a reduction in the transmission rate of rotavirus in the hospital. Both CA and HA rotavirus rates remained much lower in the 2008–2009 than in the 2003–2007 seasons.

CONCLUSIONS:

Community-based rotavirus vaccination is associated with a substantial reduction in the number of children who are admitted with rotavirus. These data also indicate that routine community-based rotavirus infant vaccination protects hospitalized children from acquiring rotavirus. Vaccination efforts should be encouraged as a strategy to affect the substantial burden of HA rotavirus.
Intima-Media Thickness and Flow-Mediated Dilatation in the Helsinki Study of Very Low Birth Weight Adults
Authors: Hovi Petteri , Turanlahti Maila , Strang-Karlsson Sonja , Wehkalampi Karoliina , Järvenpää Anna-Liisa , Eriksson Johan G. , Kajantie Eero , Andersson Sture
Published: January 2011

BACKGROUND:

Adults born at a very low birth weight (VLBW) (< 1500 g), compared with those born at term, bear risk factors for cardiovascular disease, including higher blood pressure and insulin resistance.

OBJECTIVE:

We studied, in young adults born at a VLBW, early signs of an accelerated atherosclerotic process and the relationship of these signs with postnatal growth.

METHODS:

We compared 92 with a VLBW with 68 who were born at term. At age 18 to 27, we measured stiffness and intima-media thickness (IMT) of the right carotid artery and flow-mediated dilatation (FMD) of the right brachial artery.

RESULTS:

Those with a VLBW had 1.1% units higher FMD (95% confidence interval [CI]: 0.0–2.2) (P = .06) and 0.5% units higher IMT relative to lumen size (95% CI: 0.1–0.9). IMT or FMD, when analyzed as the absolute change in millimeters, and carotid stiffness in the groups were similar. Among those with a VLBW, each 100-g-greater weight gain during the first 2 postnatal weeks predicted 1.1% units higher FMD (95% CI: 0.2–2.0) in adulthood.

CONCLUSIONS:

Although young adults born at VLBWs, compared with those born at term, have higher levels of risk factors for cardiovascular disease, we found no clear evidence for elevated early markers of atherosclerosis. However, in relation to artery lumen diameter, IMT in the participants who had a VLBW was higher than in those who were born at term. In our study, weight gain during the first postnatal weeks had no harmful effect on the arteries in young adulthood.
Early Experiences and Predictors of Recruitment Success for the National Children's Study
Authors: Trasande Leonardo , Andrews Howard F. , Goranson Christopher , Li Wenhui , Barrow Elise C. , VanderBeek Suzette B. , McCrary Brittany , Allen Suzannah B. , Gallagher Kathleen D. , Rundle Andrew , Quinn James , Brenner Barbara
Published: January 2011

OBJECTIVES:

We aimed to describe 17 months of experience with household recruitment of live births for the National Children's Study in Queens, a highly urban, diverse borough of New York City (NYC), and to assess predictors of recruitment success.

METHODS:

Recruitment data (enumeration, pregnancy screening of age-eligible women, identification of pregnancies, and consent) for the period of January 2009 through May 2010 were calculated. Geographic information systems were used to create 11 community-level variables for each of the 18 study segments where recruitment occurred, using US Census, NYC Office of Vital Statistics, NYC Department of City Planning, and NYC Police Department data. Recruitment yields were analyzed with respect to these variables at the segment level.

RESULTS:

Enumeration identified 4889 eligible women, of whom 4333 (88.6%) completed the pregnancy screener. At least 115 births were lost because of an inability of the pregnancy screener to identify pregnant women, whereas another 115 could be expected to be lost because of missed enumerations and pregnancy screeners. The consent rate was 60.3%. Segments with higher percentages of low birth weight had higher enumeration, pregnancy screening, and consent rates.

CONCLUSIONS:

In a highly immigrant, urban setting, households could be approached for recruitment of women to participate in the National Children's Study with consent rates equal to those experienced in clinical settings. Refinement of the pregnancy screener and other recruitment materials presents an opportunity to optimize recruitment, improve the representativeness of study participants, and improve the cost-effectiveness of study execution.
Meaning without Words: The Contrast between Artha and Ruta in Mah?y?na S?tras.
Authors: Lugli Ligeia
Published: January 2011

This paper explores the contrast between words (ruta) and meaning (artha) as it emerges from those Mah?y?na s?tras that discuss the issue most extensively. For these texts artha is out of the reach of language. Some declare it inexpressible, some view words and meaning as mutually exclusive, while still others warn of verbalization as a danger to the realization of artha. Their concerns do not spring from semantics, but derive from their conception of reality as sameness.
Manipulating Meaning: Daniel Gogerly's Nineteenth Century Translations of the Theravada Texts
Authors: Harris Elizabeth J.
Published: January 2011

Daniel John Gogerly (1792–1862), a British Wesleyan Methodist missionary, served in Sri Lanka from 1818 until his death. He learnt P?li in M?tara in the 1830s and was one of the first British translators of the P?li texts into English. Praised by fellow orientalist, T.W. Rhys Davis, as ‘the greatest Pali scholar of his age’ and hailed by his missionary colleagues as the expert who showed them how to attack Buddhism, his work was both pioneering and deeply flawed. This paper first situates Gogerly in his missionary context and then examines one translation — the first 18 vaggas of the Dhammapada, using three versions, one of which was an unpublished rough translation. It demonstrates that Gogerly, in spite of a commendable wish to be just to Buddhism, used his translations to highlight difference between Buddhism and Christianity in furtherance of his missionary agenda. Gogerly is important not only because his translations were so early but also because the differing factors that conditioned them underscore the complexity within any study of orientalist representations of Buddhism.
Tibetan Buddhist Ethnography: Deficiencies, Developments, and Future Directions
Authors: Owen Mark
Published: January 2011

In recent years scholars working in the area of Religious Studies have increasingly been obliged to acknowledge that the level of methodological rigour displayed in many studies on religious phenomena is unsatisfactory, perhaps particularly when compared to that of some academics operating in related subject areas. Arguably one of the principal areas in which an apparent reticence to engage with contemporary developments in method is evident is that of ‘religious ethnography’. The purpose of this short study is to assess the extent to which ethnographic practices in the study of Tibetan Buddhism have historically responded to methodological developments in ethnography and anthropology, and to briefly suggest ways in which studies in this area may progress in the future.