bluuebunny/crossref_metadata_2025 huggingface dataset:
The transmission of mother-child boundary disturbances across three generations
Authors: Jacobvitz Deborah B. , Morgan Elizabeth , Kretchmar Molly D. , Morgan Yvonne
Published: September 2009

Attachment theory and family systems perspectives were used to explore the intergenerational origins of an overinvolved, symbiotic parenting pattern that hampers children's emerging autonomy. Consistent with principles of developmental psychopathology, the same underlying relationship disturbance was expected to manifest differently at different times in the developmental process. Specifically, links among maternal intrusiveness during infancy, overprotection during childhood, and mother-child role-reversal during young adulthood were explored. Forty-nine maternal grandmothers, mothers, and firstborn infants were visited in the mothers' homes when the infants were 6 and 9 months old. Grandmothers' memories of overprotection were related to observational ratings of high boundary dissolution and low positive affectivity with the mothers. No significant relationships were found between mothers' past and current relationships with the grandmothers. Yet, mothers' memories of overprotection during childhood or their current participation in unaffectionate, enmeshed, and role-reversed relationships with their mothers forecast their intrusive care with their own infants. Moreover, mothers' memories of overprotection related to their beliefs that others cannot be trusted and these beliefs were related, in turn, to observations of their intrusive care at 9 months. The implications of understanding the origins of maternal intrusiveness for developing prevention programs are discussed.
Are fish eaters healthier and do they consume less health-care resources?
Authors: Hostenkamp Gisela , Sørensen Jan
Published: September 2009

Objective

Regular dietary intake of fish is associated with reduced risk of developing cardiovascular and other chronic diseases, and may improve general well-being. If fish eaters are healthier, they may use fewer health-care resources. The present study aimed to describe the reported intake of fish and fish products in a Danish general population, and to investigate whether fish consumption is associated with generic measures of self-reported health and consumption of health-care resources.

Design

Data on eating patterns and health status for 3422 Danish adults were obtained by telephone interview in the Funen County Health Survey. These data were merged with individual-level register data on health-care utilisation. Survey respondents were categorised into those consuming fish at least once weekly (fish eaters) and those consuming fish less frequently (non-fish eaters).

Results

People who reported eating fish twice monthly or once weekly had significantly better overall self-reported health than those who rarely eat fish, even after adjustment for age, gender, social characteristics and lifestyle factors. Fish eaters did not have significantly lower aggregated health-care costs, although their hospital utilisation was significantly lower than that for non-fish eaters.

Conclusions

Moderate fish consumption was associated with better self-reported general health even after controlling for possible confounding variables. Overall, fish eaters appeared to use the same amount of health-care resources as non-eaters, although fish eaters used more medicine but were less likely to be admitted to a hospital.
Equity in Irish health care financing: measurement issues
Authors: Smith Samantha
Published: September 2009

This paper employs widely used analytic techniques for measuring equity in health care financing to update Irish results from previous analysis based on data from the late 1980s. Kakwani indices are calculated using household survey data from 1987/88 to 2004/05. Results indicate a marginally progressive financing system overall. However, interpretation of the results for the private sources of health financing is complicated. This problem is not unique to Ireland but it is argued that it may be relatively more important in the context of a complex health financing system, illustrated in this paper by the Irish system. Alternative options for improving the analysis of equity in health care financing are discussed.
How to measure dyspnea in acute heart failure?
Authors: Socrates Thenral , Mebazaa Alexandre
Published: September 2009

Dyspnea is the most common presenting symptom of patients with acute heart failure (AHF). Although dyspnea is an important target for treatment in clinical practice and clinical trials, there remains a lack of consensus on how to assess it. We describe and recommend to use absolute scales such the Likert 5-point or the Visual Analogue Scale rather than any comparator scale such as the Likert 7-point scale. We further recommend starting dyspnea measurements in sitting position and perform, if possible, similar measurements in lying position. The same set of measurements may be repeated as needed during the time course of disease and the treatment.
Global temperature stationary planetary waves extending from 20 to 120 km observed by TIMED/SABER
Authors: Xiao Cunying , Hu Xiong , Tian Jianhua
Published: September 2009

Version 1.07 temperature measurements from SABER instrument on board of TIMED satellite during 2006–2007 are used to study the temperature stationary planetary waves (SPWs) from 20 to 120 km. To cover the high latitudes in both hemispheres (80°S–80°N) and most local times, 120‐day data are combined together into one data set. The most pronounced SPW features are the large amplitudes in the upper mesosphere and lower thermosphere (UMLT), while the SPWs below 90–95 km share common features with previous observations. In both hemispheric UMLT, SPWs amplitudes are large at middle and high latitudes throughout the year while their amplitudes in tropics are small. Wave 1 activity is generally stronger than the corresponding wave 2 activity with maximum amplitudes larger than 15 K, occurring at about 60°–70° north or south at the altitudes between 112 km and 119 km. Wave 1 amplitudes are larger in the Southern Hemisphere (SH) than in the Northern Hemisphere (NH). Their phases are normally tilt westward with increasing height below ∼110 km. Above this altitude, the wave 1 and wave 2 phases remain nearly unchanged with height, indicating the in situ generations and no propagations. Comparisons between the observed SPW structures and those from the NRLMSISE‐00 model have been done. Result shows their consistent features below ∼80 km and that NRLMSISE‐00 model gives no SPW information from 95 to 125 km but does have longitudinal variations above ∼125 km that are similar to the observed SPW features above ∼110 km.
Mineral dust and elemental black carbon records from an Alpine ice core (Colle Gnifetti glacier) over the last millennium
Authors: Thevenon Florian , Anselmetti Flavio S. , Bernasconi Stefano M. , Schwikowski Margit
Published: September 2009

Black carbon (BC) and mineral dust aerosols were analyzed in an ice core from the Colle Gnifetti glacier (Monte Rosa, Swiss‐Italian Alps, 45°55′N, 7°52′E, 4455 m above sea level) using chemical and optical methods. The resulting time series obtained from this summer ice record indicate that BC transport was primarily constrained by regional anthropogenic activities, i.e., biomass and fossil fuel combustion. More precisely, the δ13C composition of BC suggests that wood combustion was the main source of preindustrial atmospheric BC emissions (C3:C4 ratio of burnt biomass of 75:25). Despite relatively high BC emissions prior to 1570, biomass burning activity and especially C4 grassland burning abruptly dropped between 1570 and 1750 (C3:C4 ratio of burnt biomass of 90:10), suggesting that agricultural practices strongly decreased in Europe during this cold period of the “Little Ice Age” (LIA). On the other hand, optical analysis revealed that the main source for atmospheric dust transport to the southern parts of the Alps during summer months was driven by large‐scale atmospheric circulation control on the dust export from the northern Saharan desert. This southern aerosol source was probably associated with global‐scale hydrologic changes, at least partially forced by variability in solar irradiance. In fact, periods of enhanced Saharan dust deposition in the ice core (around 1200–1300, 1430–1520, 1570–1690, 1780–1800, and after 1870) likely reflect drier winters in North Africa, stronger North Atlantic southwesterlies, and increased spring/summer precipitation in west‐central Europe. These results, therefore, suggest that the climatic pejorations and the resulting socioeconomic crises, which occurred in Europe during periods of the LIA, could have been indirectly triggered by large‐scale meridional advection of air masses and wetter summer climatic conditions.
On the development of strong ridge episodes over the eastern North Atlantic
Authors: Santos João A. , Pinto Joaquim G. , Ulbrich Uwe
Published: September 2009

The occurrence of strong and persistent mid‐latitude anticyclonic ridges over the Eastern North Atlantic is a major contributor to the occurrence of severe winter droughts over Western Iberia. We analyze the development of strong and persistent ridge episodes within 40–50°N; 40°W–5°E, which are defined as 300 hPa geopotential height anomalies above 50 gpm that persist for at least 10 consecutive days. Results suggest that the generation and maintenance of these episodes, with positive stratospheric geopotential anomalies over the North American continent and the adjacent North Pacific, are associated with an intensified polar jet. Such positive anomalies tend to detach from the main stratospheric anomaly and propagate eastwards and downwards as Rossby tropospheric waves. Furthermore, the Eastern North Atlantic ridge is generated and repeatedly reinforced until the stratospheric anomaly dissipates. Results also show evidence for waves breaking anticyclonically during the episodes, which is dynamically coherent with their persistency and quasi‐stationarity.
Detecting a mass change inside a volcano by cosmic‐ray muon radiography (muography): First results from measurements at Asama volcano, Japan
Authors: Tanaka Hiroyuki K. M. , Uchida Tomihisa , Tanaka Manobu , Takeo Minoru , Oikawa Jun , Ohminato Takao , Aoki Yosuke , Koyama Etsuro , Tsuji Hiroshi
Published: September 2009

A visual detection and monitoring of volcanic eruptions is the most essential information. In February 2, 2009, Asama volcano, Japan erupted and a large amount of volcanic ash was ejected from the vent. We have observed the activity at Asama since October 12, 2008. For eruption monitoring we used cosmic‐ray muon radiography (muography), a new volcano monitoring system recently developed by Tanaka et al. (2009). We measured a quantitative mass loss inside the crater during the eruption event although no changes were found below the crater. The measured value of 30,780 tons is consistent with a model calculation of volcanic ash flow as observed on February 2, 2009. The obtained radiographic image suggests that a “boiling liquid expanding vapor explosion” occurred and a part of an old lava mound was exploded. This picture is consistent with the analytical result of the volcanic ash ejected on February 2, 2009.
The functional impairment of natural killer cells during influenza virus infection
Authors: Guo Hailong , Kumar Pawan , Moran Thomas M , Garcia‐Sastre Adolfo , Zhou Yan , Malarkannan Subramaniam
Published: September 2009

Natural killer (NK) cells have a critical role in clearing influenza virus, which primarily infects the lung epithelial cells. However, the ability of influenza virus to infect and manipulate NK cells has not been studied. In this context, we hypothesized that influenza virus can target NK cells leading to a functional impairment in their ability to mediate cytotoxicity and cytokine/chemokine generations. Here, we show influenza virus, PR8, can enter and infect NK cells. This infection did not alter the expression levels of activating, inhibitory or developmental receptors of NK cells. However, infection of NK cells by PR8 reduced the cytotoxicity to tumor cells that represent ‘induced‐self’ and ‘missing‐self’. PR8‐infection also significantly downregulated the NCR1, NKG2D, Nkpr1c, Ly49D and CD244 receptors‐mediated generation of pro‐inflammatory cytokines and chemokines. Mutations in the non‐structural protein 1 (NS1) of influenza virus further augmented the functional impairment of NK cells. Our observations show the presence of a new, but yet to be explored, mechanism by which the influenza virus can evade immune detection.
Early commitment of naïve human CD4+ T cells to the T follicular helper (TFH) cell lineage is induced by IL‐12
Authors: Ma Cindy S , Suryani Santi , Avery Danielle T , Chan Anna , Nanan Ralph , Santner‐Nanan Brigitte , Deenick Elissa K , Tangye Stuart G
Published: September 2009

T follicular helper (TFH) cells are a specialized subset of CD4+ T cells that localize to B‐cell follicles, where they are positioned to provide help for the induction of optimal humoral immune responses. Key features of TFH cells are the expressions of CXCR5, ICOS, interleukin (IL)‐21 and BCL‐6. The requirements for human TFH cell development are unknown. Here we show that IL‐6, IL‐12, IL‐21 and IL‐23 are capable of inducing IL‐21 expression in naïve CD4+ T cells isolated from human tonsils, peripheral blood and cord blood. However, only IL‐12 induced sustained expressions of CXCR5 and ICOS on these activated naïve CD4+ T cells, and endowed them with the ability to provide increased help to B cells for their differentiation into immunoglobulin‐secreting cells. The effects of IL‐12 were independent of interferon‐γ and T‐bet, and associated with upregulation of BCL‐6 expression. Thus, these cytokines, particularly IL‐12, are likely to act at an early stage during dendritic cell‐mediated priming of naïve CD4+ T cells into a TFH cell fate, and thus underpin antibody‐mediated immunity.
Investigation of the Adsorption Characteristics of Antimony, Cadmium, and Lead by Nano- and Microparticle Titania
Authors: Zia Jared , Amarasiriwardena Dula , Xing Baoshan
Published: September 2009

The utilization of nanotechnology is expected to rise greatly within the next decade. The increasing ubiquity of nanotechnology, coupled with the fact that the toxicity of a nanomaterial is partially dependent on its adsorbed components, emphasizes the general importance, and environmental significance, of nanomaterial adsorption studies. Using nanoparticle titania (and microparticle titania for comparison), a series of adsorption experiments were performed. The antimony, lead, and cadmium adsorption capacity of nanoparticle titania was compared to that of microparticle titania. During a typical adsorption experiment, a known amount of nanomaterial was shaken with a solution containing a known concentration of antimony, lead, and cadmium. Following an equilibration period, the solutions were filtered, centrifuged, and analyzed using either inductively coupled plasma - mass spectrometry (ICP-MS), or inductively coupled plasma - atomic emission spectroscopy (ICP-AES). The effect of light and adsorption on antimony speciation was also investigated by using high performance liquid chromatography (HPLC) in conjunction with ICP-MS. Adsorption experiments indicate that nanoparticle titania has a higher adsorption affinity for antimony, cadmium, and lead species when compared to microparticle titania. Langmuir and Freundlich isotherm plots were created, and it was determined that both isotherms provided a good fit for the data. Results of the antimony speciation studies indicate that Sb(III) was oxidized to Sb(V) and adsorbed by microparticle titania; Sb(III) oxidation cannot be confirmed when nanoparticle titania is used as the adsorbent, as complete antimony adsorption always occurred at the concentrations studied. The presence of ambient light had only a small effect on adsorption and oxidation; antimony adsorption by microparticle titania was more complete in the absence of light.
Satellite altimetry quantifies the alarming thinning of Arctic sea ice
Authors: Wilson Mark
Published: September 2009

A dramatic 57% loss in the volume of perennial ice between 2004 and 2008 may have set the stage for ice-free summers within the next 30 years.
Thermochronology and landscape evolution
Authors: Reiners Peter W. , Shuster David L.
Published: September 2009

Radioactive decay, the diffusion of daughter nuclides, and the annealing of fission tracks are being used to develop time-versus-temperature histories of rocks and the processes that sculpt Earth’s surface.
Friction, force chains, and falling fruit
Authors: Krim Jacqueline , Behringer Robert P.
Published: September 2009

Why is it that stacked apples seem so stable, but removing the “wrong” apple can cause the whole pile to tumble down?
The Aharonov–Bohm effects: Variations on a subtle theme
Authors: Batelaan Herman , Tonomura Akira
Published: September 2009

The notion, introduced 50 years ago, that electrons could be affected by electromagnetic potentials without coming in contact with actual force fields was received with a skepticism that has spawned a flourishing of experimental tests and expansions of the original idea.
Solid-state NMR in biological and materials physics
Authors: Grey Clare P. , Tycko Robert
Published: September 2009

Ever-improving techniques for manipulating and probing nuclear spins make it possible to obtain detailed structural information about large molecules and disordered compounds.
High-field MRI reveals an acute impact on brain function in survivors of the magnitude 8.0 earthquake in China
Authors: Lui Su , Huang Xiaoqi , Chen Long , Tang Hehan , Zhang Tijiang , Li Xiuli , Li Dongming , Kuang Weihong , Chan Raymond C. , Mechelli Andrea , Sweeney John A. , Gong Qiyong
Published: September 2009

Besides the enormous medical and economic consequences, national disasters, such as the Wenchuan 8.0 earthquake, also pose a risk to the mental health of survivors. In this context, a better understanding is needed of how functional brain systems adapt to severe emotional stress. Previous animal studies have demonstrated the importance of limbic, paralimbic, striatal, and prefrontal structures in stress and fear responses. Human studies, which have focused primarily on patients with clinically established posttraumatic stress disorders, have reported abnormalities in similar brain structures. At present, little is known about potential alterations of brain function in trauma survivors shortly after traumatic events. Here, we show alteration of brain function in a cohort of healthy survivors within 25 days after the Wenchuan earthquake by a recently discovered method known as “resting-state” functional MRI. The current investigation demonstrates that regional activity in frontolimbic and striatal areas increased significantly and connectivity among limbic and striatal networks was attenuated in our participants who had recently experienced severe emotional trauma. Trauma victims also had a reduced temporal synchronization within the “default mode” of resting-state brain function, which has been characterized in humans and other species. Taken together, our findings provide evidence that significant alterations in brain function, similar in many ways to those observed in posttraumatic stress disorders, can be seen shortly after major traumatic experiences, highlighting the need for early evaluation and intervention for trauma survivors.
Molecular random tilings as glasses
Authors: Garrahan Juan P. , Stannard Andrew , Blunt Matthew O. , Beton Peter H.
Published: September 2009

We have recently shown thatp-terphenyl-3,5,3′,5′-tetracarboxylic acid adsorbed on graphite self-assembles into a two-dimensional rhombus random tiling. This tiling is close to ideal, displaying long-range correlations punctuated by sparse localized tiling defects. In this article we explore the analogy between dynamic arrest in this type of random tilings and that of structural glasses. We show that the structural relaxation of these systems is via the propagation–reaction of tiling defects, giving rise to dynamic heterogeneity. We study the scaling properties of the dynamics and discuss connections with kinetically constrained models of glasses.
Imaging intracellular pH in a reef coral and symbiotic anemone
Authors: Venn A. A. , Tambutté E. , Lotto S. , Zoccola D. , Allemand D. , Tambutté S.
Published: September 2009

The challenges corals and symbiotic cnidarians face from global environmental change brings new urgency to understanding fundamental elements of their physiology. Intracellular pH (pHi) influences almost all aspects of cellular physiology but has never been described in anthozoans or symbiotic cnidarians, despite its pivotal role in carbon concentration for photosynthesis and calcification. Using confocal microscopy and the pH sensitive probe carboxy SNARF-1, we mapped pHi in short-term light and dark-incubated cells of the reef coral
Stylophora pistillata
and the symbiotic anemone
Anemonia viridis
. In all cells isolated from both species, pHi was markedly lower than the surrounding seawater pH of 8.1. In cells that contained symbiotic algae, mean values of pHi were significantly higher in light treated cells than dark treated cells (7.41 ± 0.22 versus 7.13 ± 0.24 for
S. pistillata
; and 7.29 ± 0.15 versus 7.01 ± 0.27 for
A. viridis
). In contrast, there was no significant difference in pHi in light and dark treated cells without algal symbionts. Close inspection of the interface between host cytoplasm and algal symbionts revealed a distinct area of lower pH adjacent to the symbionts in both light and dark treated cells, possibly associated with the symbiosome membrane complex. These findings are significant developments for the elucidation of models of inorganic carbon transport for photosynthesis and calcification and also provide a cell imaging procedure for future investigations into how pHi and other fundamental intracellular parameters in corals respond to changes in the external environment such as reductions in seawater pH.
Structural basis for ligand and substrate recognition by torovirus hemagglutinin esterases
Authors: Langereis Martijn A. , Zeng Qinghong , Gerwig Gerrit J. , Frey Barbara , Itzstein Mark von , Kamerling Johannis P. , de Groot Raoul J. , Huizinga Eric G.
Published: September 2009

Hemagglutinin esterases (HEs), closely related envelope glycoproteins in influenza C and corona- and toroviruses, mediate reversible attachment to
O
-acetylated sialic acids (Sias). They do so by acting both as lectins and as receptor-destroying enzymes, functions exerted by separate protein domains. HE divergence was accompanied by changes in quaternary structure and in receptor and substrate specificity. The selective forces underlying HE diversity and the molecular basis for Sia specificity are poorly understood. Here we present crystal structures of porcine and bovine torovirus HEs in complex with receptor analogs. Torovirus HEs form homodimers with sialate-
O
-acetylesterase domains almost identical to corresponding domains in orthomyxo- and coronavirus HEs, but with unique lectin sites. Structure-guided biochemical analysis of the esterase domains revealed that a functionally, but not structurally conserved arginine–Sia carboxylate interaction is critical for the binding and positioning of glycosidically bound Sias in the catalytic pocket. Although essential for efficient de-
O
-acetylation of Sias, this interaction is not required for catalysis nor does it affect substrate specificity. In fact, the distinct preference of the porcine torovirus enzyme for 9-mono- over 7,9-di-
O
-acetylated Sias can be explained from a single-residue difference with HEs of more promiscuous specificity. Apparently, esterase and lectin pockets coevolved; also the porcine torovirus HE receptor-binding site seems to have been designed to use 9-mono- and exclude di-
O
-acetylated Sias, possibly as an adaptation to replication in swine. Our findings shed light on HE evolution and provide fundamental insight into mechanisms of substrate binding, substrate recognition, and receptor selection in this important class of virion proteins.
Visualization of ATP levels inside single living cells with fluorescence resonance energy transfer-based genetically encoded indicators
Authors: Imamura Hiromi , Huynh Nhat Kim P. , Togawa Hiroko , Saito Kenta , Iino Ryota , Kato-Yamada Yasuyuki , Nagai Takeharu , Noji Hiroyuki
Published: September 2009

Adenosine 5′-triphosphate (ATP) is the major energy currency of cells and is involved in many cellular processes. However, there is no method for real-time monitoring of ATP levels inside individual living cells. To visualize ATP levels, we generated a series of fluorescence resonance energy transfer (FRET)-based indicators for ATP that were composed of the ε subunit of the bacterial F
o
F
1
-ATP synthase sandwiched by the cyan- and yellow-fluorescent proteins. The indicators, named ATeams, had apparent dissociation constants for ATP ranging from 7.4 μM to 3.3 mM. By targeting ATeams to different subcellular compartments, we unexpectedly found that ATP levels in the mitochondrial matrix of HeLa cells are significantly lower than those of cytoplasm and nucleus. We also succeeded in measuring changes in the ATP level inside single HeLa cells after treatment with inhibitors of glycolysis and/or oxidative phosphorylation, revealing that glycolysis is the major ATP-generating pathway of the cells grown in glucose-rich medium. This was also confirmed by an experiment using oligomycin A, an inhibitor of F
o
F
1
-ATP synthase. In addition, it was demonstrated that HeLa cells change ATP-generating pathway in response to changes of nutrition in the environment.
Regulation of pre-otic brain development by the cephalic neural crest
Authors: Creuzet Sophie E.
Published: September 2009

Emergence of the neural crest (NC) is considered an essential asset in the evolution of the chordate phylum, as specific vertebrate traits such as peripheral nervous system, cephalic skeletal tissues, and head development are linked to the NC and its derivatives. It has been proposed that the emergence of the NC was responsible for the formation of a “new head” characterized by the spectacular development of the forebrain and associated sense organs. It was previously shown that removal of the cephalic NC (CNC) prevents the formation of the facial structures but also results in anencephaly. This article reports on the molecular mechanisms whereby the CNC controls cephalic neurulation and brain morphogenesis. This study demonstrates that molecular variations of Gremlin and Noggin level in CNC account for morphological changes in brain size and development. CNC cells act in these processes through a multi-step control and exert cumulative effects counteracting bone morphogenetic protein signaling produced by the neighboring tissues (e.g., adjacent neuroepithelium, ventro-medial mesoderm, superficial ectoderm). These data provide an explanation for the fact that acquisition of the NC during the protochordate-to-vertebrate transition has coincided with a large increase of brain vesicles.
Oxygen-mediated enhancement of primary hepatocyte metabolism, functional polarization, gene expression, and drug clearance
Authors: Kidambi Srivatsan , Yarmush Rubin S. , Novik Eric , Chao Piyun , Yarmush Martin L. , Nahmias Yaakov
Published: September 2009

The liver is a major site for the metabolism of xenobiotic compounds due to its abundant level of phase I/II metabolic enzymes. With the cost of drug development escalating to over $400 million/drug there is an urgent need for the development of rigorous models of hepatic metabolism for preclinical screening of drug clearance and hepatotoxicity. Here, we present a microenvironment in which primary human and rat hepatocytes maintain a high level of metabolic competence without a long adaptation period. We demonstrate that co-cultures of hepatocytes and endothelial cells in serum-free media seeded under 95% oxygen maintain functional apical and basal polarity, high levels of cytochrome P450 activity, and gene expression profiles on par with freshly isolated hepatocytes. These oxygenated co-cultures demonstrate a remarkable ability to predict in vivo drug clearance rates of both rapid and slow clearing drugs with an
R
2
of 0.92. Moreover, as the metabolic function of oxygenated co-cultures stabilizes overnight, preclinical testing can be carried out days or even weeks before other culture methods, significantly reducing associated labor and cost. These results are readily extendable to other culture configurations including three-dimensional culture, bioreactor studies, as well as microfabricated co-cultures.
Evidence from ammonoids and conodonts for multiple Early Triassic mass extinctions
Authors: Stanley Steven M.
Published: September 2009

Ammonoids and conodonts, being characterized by exceptionally high background rates of origination and extinction, were vulnerable to global environmental crises, which characteristically intensified background rates of extinction. Thus, it is not surprising that these taxa suffered conspicuous mass extinctions at the times of three negative Early Triassic global carbon isotopic excursions that resembled those associated with the two preceding Permian mass extinctions. In keeping with their high rates of origination, both the ammonoids and conodonts rediversified dramatically between the Early Triassic crises. Other marine taxa, characterized by much lower intrinsic rates of origination, were held at low levels of diversity by the Early Triassic crises; because global mass extinctions affect all marine life, these taxa must have experienced relatively modest expansions and contractions that have yet to be discovered, because they do not stand out in the fossil record and because the stratigraphic ranges of these taxa, being of little value for temporal correlation, have not been thoroughly studied.
A broad screen for targets of immune complexes decorating arthritic joints highlights deposition of nucleosomes in rheumatoid arthritis
Authors: Monach Paul A. , Hueber Wolfgang , Kessler Benedikt , Tomooka Beren H. , BenBarak Maya , Simmons Barry P. , Wright John , Thornhill Thomas S. , Monestier Marc , Ploegh Hidde , Robinson William H. , Mathis Diane , Benoist Christophe
Published: September 2009

Deposits of Ig and complement are abundant in affected joints of patients with rheumatoid arthritis (RA) and in animal models of RA in which antibodies are demonstrably pathogenic. To identify molecular targets of the Igs deposited in arthritic joints, which may activate local inflammation, we used a combination of mass spectrometry (MS) and protein microarrays. Immune complexes were affinity-purified from surgically removed joint tissues of 26 RA and osteoarthritis (OA) patients. Proteins complexed with IgG were identified by proteomic analysis using tandem MS. A striking diversity of components of the extracellular matrix, and some intracellular components, copurified specifically with IgG from RA and OA tissues. A smaller set of autoantigens was observed only in RA eluates. In complementary experiments, IgG fractions purified from joint immune complexes were tested on protein microarrays against a range of candidate autoantigens. These Igs bound a diverse subset of proteins and peptides from synovium and cartilage, different from that bound by normal serum Ig. One type of intracellular protein detected specifically in RA joints (histones H2A/B) was validated by immunohistology and found to be deposited on the cartilage surface of RA but not OA joints. Thus, autoantibodies to many determinants (whether deposited as “neoantigens” or normal constituents of the extracellular matrix) have the potential to contribute to arthritic inflammation.
Redox signaling between DNA repair proteins for efficient lesion detection
Authors: Boal Amie K. , Genereux Joseph C. , Sontz Pamela A. , Gralnick Jeffrey A. , Newman Dianne K. , Barton Jacqueline K.
Published: September 2009

Base excision repair (BER) enzymes maintain the integrity of the genome, and in humans, BER mutations are associated with cancer. Given the remarkable sensitivity of DNA-mediated charge transport (CT) to mismatched and damaged base pairs, we have proposed that DNA repair glycosylases (EndoIII and MutY) containing a redox-active [4Fe4S] cluster could use DNA CT in signaling one another to search cooperatively for damage in the genome. Here, we examine this model, where we estimate that electron transfers over a few hundred base pairs are sufficient for rapid interrogation of the full genome. Using atomic force microscopy, we found a redistribution of repair proteins onto DNA strands containing a single base mismatch, consistent with our model for CT scanning. We also demonstrated in
Escherichia coli
a cooperativity between EndoIII and MutY that is predicted by the CT scanning model. This relationship does not require the enzymatic activity of the glycosylase. Y82A EndoIII, a mutation that renders the protein deficient in DNA-mediated CT, however, inhibits cooperativity between MutY and EndoIII. These results illustrate how repair proteins might efficiently locate DNA lesions and point to a biological role for DNA-mediated CT within the cell.
Cells satisfy the mitotic checkpoint in Taxol, and do so faster in concentrations that stabilize syntelic attachments
Authors: Yang Zhenye , Kenny Alison E. , Brito Daniela A. , Rieder Conly L.
Published: September 2009

To determine why the duration of mitosis (DM) is less in Taxol than in nocodazole or Eg5 inhibitors we studied the relationship between Taxol concentration, the DM, and the mitotic checkpoint. We found that unlike for other spindle poisons, in Taxol the DM becomes progressively shorter as the concentration surpasses ∼0.5 µM. Studies on RPE1 and PtK2 expressing GFP/cyclin B or YFP/Mad2 revealed that cells ultimately satisfy the checkpoint in Taxol and do so faster at concentrations >0.5 µM. Inhibiting the aurora-B kinase in Taxol-treated RPE1 cells accelerates checkpoint satisfaction by stabilizing syntelic kinetochore attachments and reduces the DM to ∼1.5 h regardless of drug concentration. A similar stabilization of syntelic attachments by Taxol itself appears responsible for accelerated checkpoint satisfaction at concentrations >0.5 µM. Our results provide a novel conceptual framework for how Taxol prolongs mitosis and caution against using it in checkpoint studies. They also offer an explanation for why some cells are more sensitive to lower versus higher Taxol concentrations.
Activating receptors promote NK cell expansion for maintenance, IL-10 production, and CD8 T cell regulation during viral infection
Authors: Lee Seung-Hwan , Kim Kwang-Sin , Fodil-Cornu Nassima , Vidal Silvia M. , Biron Christine A.
Published: September 2009

Natural killer (NK) cells have the potential to deliver both direct antimicrobial effects and regulate adaptive immune responses, but NK cell yields have been reported to vary greatly during different viral infections. Activating receptors, including the Ly49H molecule recognizing mouse cytomegalovirus (MCMV), can stimulate NK cell expansion. To define Ly49H's role in supporting NK cell proliferation and maintenance under conditions of uncontrolled viral infection, experiments were performed in Ly49h−/−, perforin 1 (Prf1)−/−, and wild-type (wt) B6 mice. NK cell numbers were similar in uninfected mice, but relative to responses in MCMV-infected wt mice, NK cell yields declined in the absence of Ly49h and increased in the absence of Prf1, with high rates of proliferation and Ly49H expression on nearly all cells. The expansion was abolished in mice deficient for both Ly49h and Prf1 (Ly49h−/−Prf1−/−), and negative consequences for survival were revealed. The Ly49H-dependent protection mechanism delivered in the absence of Prf1 was a result of interleukin 10 production, by the sustained NK cells, to regulate the magnitude of CD8 T cell responses. Thus, the studies demonstrate a previously unappreciated critical role for activating receptors in keeping NK cells present during viral infection to regulate adaptive immune responses.
Effect of Preoperative Shampoos with Chlorhexidine or lodophor on Emergence of Resident Scalp Flora in Neurosurgery
Authors: Leclair Jeanne M. , Winston Ken R. , Sullivan Bernadette F. , O'Connell Janet M. , Harrington Stella M. , Goldmann Donald A.
Published: September 2009

Wound contamination with endogenous bacterial scalp flora plays an important role in the pathogenesis of postoperative neurosurgical infections. To assess the effect of preoperative antiseptic shampoos on the emergence of resident scalp flora during surgery and subsequent wound contamination, we randomized 151 neurosurgical procedures into four study groups: group A—preoperative shampoos with chlorhexidine, surgical scalp preparation with chlorhexidine; group B-no shampoos, surgical preparation with chlorhexidine; group C-shampoos with iodophor, surgical preparation with iodophor; group D-no shampoos, surgical preparation with iodophor. Quantitative cultures of the scalp were obtained preoperatively and at the end of surgery, and qualitative wound cultures were taken prior to wound closure. Group A had the lowest concentration of bacteria on the scalp both preoperatively and postoperatively (median range = 30 [0-5.7 × 105] and 0 [0-2.5 x 103] respectively). Group A also had significantly fewer positive postoperative scalp cultures (29%) than groups B (51%), C (58%), and D (53%) (P<0.05), as well as fewer positive wound cultures (20% v 25%, 42%, and 30% respectively). A density of bacteria on the scalp of > 102/4cm2 best predicted the presence of bacteria in the wound. Repeated preoperative shampoos with chlorhexidine reduce intraoperative emergence of resident skin flora and subsequent contamination of the wound.
Molecular and Epidemiologic Study of Multiresistant Serratia marcescens Infections in a Spinal Cord Injury Rehabilitation Unit
Authors: Simor Andrew E. , Ramage Lee , Wilcox Lindsay , Bull Shelley B. , Bialkowska-Hobrzanska Hanna
Published: September 2009

Between March 1984 and February 1986, ten patients admitted to a spinal cord injury/stroke rehabilitation unit became bacteriuric with a strain of Serratia marcescens resistant to ampicillin, cephalothin, cefoxitin, ticarcillin, cotrimoxazole, gentamicin, and tobramycin. All the patients were catheterized, and in most, bacteriuria was asymptomatic. The organism was also recovered from their hospital environment (sinks, toilets, urine-collecting basins). Analysis of total plasmid content of multiresistant isolates revealed the presence of two plasmids (7 kilobase, 25.5 kilobase), not found in aminoglycoside susceptible strains of Serratia marcescens. Restriction endonuclease analysis and Southern hybridization (DNA probe: 25.5 kilobase plasmid) verified that these plasmids were identical. The 25.5 kilobase plasmid was purified, introduced by transformation into an Escherichia coli strain C recipient, and was found to mediate resistance to gentamicin and tobramycin. The emergence of multiresistant Serratia marcescens coincided with an increase in antibiotic usage on the ward. The reservoir seemed to be the urinary tracts of asymptomatic catheterized patients and their contaminated hospital environment.
A Causal Link Between Handwashing and Risk of Infection? Examination of the Evidence
Authors: Larson Elaine
Published: September 2009

To examine evidence of a causal link between handwashing and risk of infection, a review of published literature from 1879 through 1986 was conducted. In the 107 years studied, 423 articles specifically related to handwashing were found. Articles were categorized as studies to evaluate products (50.8%), review articles (29.1%), behavioral studies (10.9%), methodologie studies (2.8%), studies linking handwashing to infection and other (3.1%). There was an increase in the proportion of handwashing articles published in the 1980s with the rate (9.4/105 citations/year) being almost double that of any other period studied. Nonexperimental and experimental studies related to handwashing were reviewed and evidence for a causal association evaluated. Except for specificity, all the elements for causality, including temporality, strength, plausibility, consistency of the association, and dose response were present. It was therefore concluded that emphasis on handwashing as a primary infection control measure has not been misplaced and should continue.
Primary Cytomegalovirus Infection in Pediatric Nurses: A Meta-Analysis
Authors: Flowers R.H. , Torner James C. , Farr Barry M.
Published: September 2009

A meta-analysis of six controlled studies was performed to evaluate the risk of cytomegalovirus (CMV) infection among pediatric nurses. The pooled risk ratio for CMV infection in pediatric nurses using cumulative incidence data was statistically significant (risk ratio [RR] 2.7; 95% confidence interval [CI] 1.33 - 5.52), but person-year analysis taking account of follow-up periods demonstrated a trend toward increased risk that failed to reach statistical significance (RR 1.8; 95% CI 0.88 - 3.55). Despite pooling, there was low statistical power for comparing person-year rates. The studies included in this analysis failed to provide data on several potential confounding variables. We conclude that studies published prior to the widespread adoption of universal precautions suggest that pediatric nurses may have been at increased risk for CMV infection due to occupational exposure, but inadequate design and sample size of the studies prevent a definitive conclusion. Well-designed, controlled studies are still needed to define the occupational risk of CMV infection.
An Outbreak of Salmonella Gastroenteritis in an Urban Jail
Authors: Alcabes Philip , O'Sullivan Barbara , Nadal Evan , Mouzon Marcia
Published: September 2009

An outbreak of gastroenteritis in New York City's largest jail involved 145 cases over a two-month period. The outbreak was unusual in that two Salmonella strains (serogroups B and D) were involved. Management of the outbreak involved screening kitchen workers by culture of stool samples, and education regarding personal hygiene. Obstacles to investigation and management of the outbreak arose out of the special nature of the jail environment; these included jurisdictional problems and high turnover of the inmate population.
Prevention of Nosocomial Transmission of Respiratory Syncytial Virus in a Newborn Nursery
Authors: Snydman David R. , Greer Cynthia , Meissner H. Cody , Mcintosh Kenneth
Published: September 2009

During three winter seasons prior to 1984-1985 the special care nursery at New England Medical Center experienced respiratory syncytial virus (RSV) epidemics that required closure of the unit. Prior to and during the 1984-1985 winter season, several measures were taken to prevent recurrent nosocomial RSV transmission. In the winters of 1984-1985 and 1985-1986 there were 26 introductions of community-acquired RSV with no transmission of nosocomial cases during 1,688 patient days at risk as compared with 1983-1984 when there were seven cases of nosocomial RSV following six introductions of RSV during 875 patient days at risk (rate = 8 per 1,000 patient days) (P = 0.0016). The institution of many infection control measures including active surveillance, cohorting infected patients, a strict winter visiting policy, and gowning, gloving, and applying mask on contact, was associated with the successful prevention of nosocomial transmission of RSV in this nursery setting.
Surgeon-Specific Wound Infection Rates-A Potentially Dangerous and Misleading Strategy
Authors: Scheckler William E.
Published: September 2009

Some colleagues are now touting the calculation and confidential reporting of surgeon-specific wound infection rates as the most important mechanism to reduce nosocomial surgical wound infections.' Several studies purport to show either a decline of surgical wound infections after such reporting is introduced or to demonstrate large differences in rates of wound infections among surgeons in a specific hospital. The purpose of this article is to clarify the numerous problems and deficiencies in the development of this concept and to show the essential statistical implausibility of demonstrating its effectiveness.
Hepatitis B Vaccine: Persistence of Antibody Following Immunization
Authors: Barnas Gary P. , Hanacik Linda J.
Published: September 2009

We examined the persistence of hepatitis B surface antibody following hepatitis B vaccination in a group of health care workers. Of the 187 vaccine recipients screened, 39 were found to be antibody negative. Life table analysis showed the proportion retaining antibody at one, two, three, and four years from the first dose of vaccine was 92%, 84%, 73%, and 55% respectively. The likelihood of retaining antibody was significantly decreased as the age of the vaccine recipient increased. These results indicate that a large proportion of vaccine recipients no longer had detectable antibody four years after receipt of the vaccine. It remains to be shown if such individuals who have lost antibody are susceptible to the development of clinical hepatitis.
Hospital Infection Surveillance in the United Kingdom
Authors: Ayliffe G.A.J.
Published: September 2009

Surveillance methods vary in different hospitals, but are mainly based on laboratory reports, as in Sweden. These reports are supplemented by ward visits by the infection control nurse and by the usual epidemiologic methods in the investigation of outbreaks.

An increasing interest in surveillance of hospital infection occurred in the 1950s when outbreaks of staphylococcal infection were causing problems throughout the world. The appointment of an MD as infection control officer in every hospital was suggested in 1955 by Colebrook in the Birmingham Accident Hospital, but no full-time officer has so far been appointed in the United Kingdom (UK). The task was taken on by medical microbiologists, who are usually physicians and, currently in England and Wales, make up 82% of infection control officers.”

In the early days, the recording of the incidence of infection was usually confined to surgical wounds, as in the US. The problem of collecting a large amount of data by the microbiologist was recognized by Moore who appointed the first infection control nurse.” He also described the importance of laboratory reports in the early detection of outbreaks.

Surveillance was a major topic for discussion at the international Conference on Nosocomial Infections in 1970, and Moore suggested that incidence rates were of little value for determining changes in a hospital or for comparisons between hospitals. The number of infections in individual hospitals was too small for statistical comparison, particularly if rates were low and infections influenced bv many factors were not corrected for in the overall rates.