bluuebunny/crossref_metadata_2025_split huggingface dataset:
Risk of Stroke in Patients Hospitalized for Isolated Vertigo
Authors: Lee Ching-Chih , Su Yu-Chieh , Ho Hsu-Chieh , Hung Shih-Kai , Lee Moon-Sing , Chou Pesus , Huang Yung-Sung 
Published: December 2010

Background and Purpose—
Vertigo is a common presenting symptom in ambulatory care settings, and stroke is its leading and most challenging concern. This study aimed to determine the risk of stroke in vertigo patients in a 4-year follow-up after hospitalization for acute isolated vertigo.

Methods—
The study cohorts consisted of all patients hospitalized with a principal diagnosis of vertigo (n=3021), whereas patients hospitalized for an appendectomy in 2004 (n=3021) comprised the control group and surrogate for the general population. Cox proportional hazard model was performed as a means of comparing the 4-year stroke-free survival rate between the 2 cohorts after adjusting for possible confounding and risk factors. Among vertigo patients, there was further stratification for risk factors to identify the group at high risk for stroke.

Results—

Of the 243 stroke patients, 185 (6.1%) were from the study cohort and 58 (1.9%) were from the control group. Comparing the 2 groups, patients with vertigo symptoms had a 3.01-times (95% CI, 2.20–4.11;
P
<0.001) higher risk for stroke after adjusting for patient characteristics, comorbidities, geographic region, urbanization level of residence, and socioeconomic status. Vertigo patients with ≥3 risk factors had a 5.51-fold higher risk for stroke (95% CI, 3.10–9.79;
P
<0.001) than those without risk factors.

Conclusions—
Vertigo patients are at higher risk for stroke than the general population. They should have a comprehensive neurological examination, vascular risk factors survey, and regular follow-up for several years after hospital discharge after treatment of isolated vertigo.
Temporal and Spatial Variations of NOx and Ozone Concentrations in Seoul during the Solar Eclipse of 22 July 2009
Authors: Kwak Kyung-Hwan , Ryu Young-Hee , Baik Jong-Jin 
Published: December 2010

Abstract
The temporal and spatial variations of NO, NO2, and O3 concentrations in Seoul, South Korea, during the solar eclipse of 22 July 2009 are investigated by analyzing data measured at 25 environmental monitoring stations. The NO2 concentration increases and the NO and O3 concentrations decrease because the efficiency of NO2 photolysis decreases during the solar eclipse. About an hour after the maximum obscuration, the reduction in the average O3 concentration over Seoul is estimated to be 45%. The maximum reduction in the O3 concentration downwind of the NOx source area is higher and occurs later than that in the downtown region. Deviations from the NO–NO2–O3 photostationary state in the downwind region are larger than those in the downtown region. This result implies that, in addition to the photochemical effect, the effect of transport by winds increases the reduction potential of the O3 concentration in the downwind region during the solar eclipse.
Response of the Hadley Circulation to Climate Change in an Aquaplanet GCM Coupled to a Simple Representation of Ocean Heat Transport
Authors: Levine Xavier J. , Schneider Tapio 
Published: December 2010

Abstract
It is unclear how the width and strength of the Hadley circulation are controlled and how they respond to climate changes. Simulations of global warming scenarios with comprehensive climate models suggest the Hadley circulation may widen and weaken as the climate warms. But these changes are not quantitatively consistent among models, and how they come about is not understood. Here, a wide range of climates is simulated with an idealized moist general circulation model (GCM) coupled to a simple representation of ocean heat transport, in order to place past and possible future changes in the Hadley circulation into a broader context and to investigate the mechanisms responsible for them.
By comparison of simulations with and without ocean heat transport, it is shown that it is essential to take low-latitude ocean heat transport and its coupling to wind stress into account to obtain Hadley circulations in a dynamical regime resembling Earth’s, particularly in climates resembling present-day Earth’s and colder. As the optical thickness of an idealized longwave absorber in the simulations is increased and the climate warms, the Hadley circulation strengthens in colder climates and weakens in warmer climates; it has maximum strength in a climate close to present-day Earth’s. In climates resembling present-day Earth’s and colder, the Hadley circulation strength is largely controlled by the divergence of angular momentum fluxes associated with eddies of midlatitude origin; the latter scale with the mean available potential energy in midlatitudes. The importance of these eddy momentum fluxes for the Hadley circulation strength gradually diminishes as the climate warms. The Hadley circulation generally widens as the climate warms, but at a modest rate that depends sensitively on how it is determined.
A New Dual-Polarization Radar Rainfall Algorithm: Application in Colorado Precipitation Events
Authors: Cifelli R. , Chandrasekar V. , Lim S. , Kennedy P. C. , Wang Y. , Rutledge S. A. 
Published: December 2010

Abstract
The efficacy of dual-polarization radar for quantitative precipitation estimation (QPE) has been demonstrated in a number of previous studies. Specifically, rainfall retrievals using combinations of reflectivity (Zh), differential reflectivity (Zdr), and specific differential phase (Kdp) have advantages over traditional Z–R methods because more information about the drop size distribution (DSD) and hydrometeor type are available. In addition, dual-polarization-based rain-rate estimators can better account for the presence of ice in the sampling volume.
An important issue in dual-polarization rainfall estimation is determining which method to employ for a given set of polarimetric observables. For example, under what circumstances does differential phase information provide superior rain estimates relative to methods using reflectivity and differential reflectivity? At Colorado State University (CSU), an optimization algorithm has been developed and used for a number of years to estimate rainfall based on thresholds of Zh, Zdr, and Kdp. Although the algorithm has demonstrated robust performance in both tropical and midlatitude environments, results have shown that the retrieval is sensitive to the selection of the fixed thresholds.
In this study, a new rainfall algorithm is developed using hydrometeor identification (HID) to guide the choice of the particular rainfall estimation algorithm. A separate HID algorithm has been developed primarily to guide the rainfall application with the hydrometeor classes, namely, all rain, mixed precipitation, and all ice.
Both the data collected from the S-band Colorado State University–University of Chicago–Illinois State Water Survey (CSU–CHILL) radar and a network of rain gauges are used to evaluate the performance of the new algorithm in mixed rain and hail in Colorado. The evaluation is also performed using an algorithm similar to the one developed for the Joint Polarization Experiment (JPOLE). Results show that the new CSU HID-based algorithm provides good performance for the Colorado case studies presented here.
Investigation of XBT and XCTD Biases in the Arabian Sea and the Bay of Bengal with Implications for Climate Studies
Authors: Boyer Tim , Gopalakrishna V. V. , Reseghetti Franco , Naik Amit , Suneel V. , Ravichandran M. , Mohammed Ali N. P. , Mohammed Rafeeq M. M. , Chico R. Anthony 
Published: December 2010

Abstract
Long time series of XBT data in the Bay of Bengal and the Arabian Sea are valuable datasets for exploring and understanding climate variability. However, such studies of interannual and longer-scale variability of temperature require an understanding, and, if possible, a correction of errors introduced by biases in the XBT and expendable conductivity–temperature–depth (XCTD) data. Two cruises in each basin were undertaken in 2008/09 on which series of tests of XBTs and XCTDs dropped simultaneously with CTD casts were performed. The XBT and XCTD depths were corrected by comparison with CTD data using a modification of an existing algorithm. Significant probe-to-probe fall-rate equation (FRE) velocity and deceleration coefficient variability was found within a cruise, as well as cruise-to-cruise variability. A small (∼0.01°C) temperature bias was also identified for XBTs on each cruise. No new FRE can be proposed for either the Bay of Bengal or the Arabian Sea for XBTs. For the more consistent XCTD, basin-specific FREs are possible for the Bay of Bengal, but not for the Arabian Sea. The XCTD FRE velocity coefficients are significantly higher than the XCTD manufacturers’ FRE coefficient or those from previous tests, possibly resulting from the influence of temperature on XCTD FRE. Mean temperature anomalies versus a long-term mean climatology for XBT data using the present default FRE have a bias (which is positive for three cruises and negative for one cruise) compared to the mean temperature anomalies for CTD data. Some improvement is found when applying newly calculated cruise-specific FREs. This temperature error must be accounted for in any study of temperature change in the regions.
Infection in infancy and subsequent risk of developing lymphoma in children and young adults
Authors: Goldin Lynn R. , Landgren Ola , Kristinsson Sigurdur Y. , Björkholm Magnus , Paltiel Ora 
Published: December 2010

Abstract
There is evidence that certain infections and autoimmunity predispose to the development of non-Hodgkin lymphomas (NHLs). A previous study reported that hospitalization for infections in infancy led to an increased risk of NHL. By using population-based registries in Sweden, we compared the rate of hospitalization for infections in infancy between lymphoma cases and matched controls for patients born since 1964. A history of infection was associated with a significantly increased risk of aggressive B-cell lymphomas (odds ratio 2.1, 95% confidence interval 1.11-4.04, P = .02). The specific infections involved were respiratory and intestinal. No effects were observed among cases of Hodgkin lymphoma. This association could result from the infection, its treatment, or could be a surrogate marker for underlying immune defects. Further studies are needed to determine whether this association is present among NHL occurring in older adults and if improved survival of patients with immune defects has contributed to the secular increases in incidence of NHLs.
Rrd1 isomerizes RNA polymerase II in response to rapamycin
Authors: Jouvet Nathalie , Poschmann Jeremie , Douville Julie , Bulet Lisa , Ramotar Dindial 
Published: December 2010

Abstract

Background
In Saccharomyces cerevisiae, the immunosuppressant rapamycin engenders a profound modification in the transcriptional profile leading to growth arrest. Mutants devoid of Rrd1, a protein possessing in vitro peptidyl prolyl cis/trans isomerase activity, display striking resistance to the drug, although how Rrd1 activity is linked to the biological responses has not been elucidated.

Results
We now provide evidence that Rrd1 is associated with the chromatin and it interacts with RNA polymerase II. Circular dichroism revealed that Rrd1 mediates structural changes onto the C-terminal domain (CTD) of the large subunit of RNA polymerase II (Rpb1) in response to rapamycin, although this appears to be independent of the overall phosphorylation status of the CTD. In vitro experiments, showed that recombinant Rrd1 directly isomerizes purified GST-CTD and that it releases RNA polymerase II from the chromatin. Consistent with this, we demonstrated that Rrd1 is required to alter RNA polymerase II occupancy on rapamycin responsive genes.

Conclusion
We propose as a mechanism, that upon rapamycin exposure Rrd1 isomerizes Rpb1 to promote its dissociation from the chromatin in order to modulate transcription.
Peripheral capillary non-perfusion in asymptomatic Waldenström's macroglobulinemia
Authors: Koutsandrea Chryssanthi , Kotsolis Athanasios , Georgalas Ilias , Papaconstantinou Dimitris , Ladas Ioannis 
Published: December 2010

Abstract

Background
To report the rare association of peripheral retinal ischemia in a patient with Waldenström's macroglobulinemia.

Case Presentation
A 39-year old man with a recent diagnosis of asymptomatic Waldenström's macroglobulinemia (WM) was referred from his physician for ocular evaluation. The fundus examination in his right eye (RE) revealed very mild central vein dilation, while retinal hemorrhages associated with microaneurismal alterations of the vascular plexus were detected at the temporal periphery. Fluoroscein angiography of his RE revealed an extended area of capillary dropout distal to the microaneurismal lesions. In our patient with WM an extensive area of capillary non-perfusion, in the absence of severe involvement of the posterior pole was documented; this association to the best of our knowledge has never been reported before.

Conclusion
Although the incidence of the disease is rare, meticulous examination of the retinal periphery should be performed in all patients with WM and vice versa the differential diagnosis of peripheral retinal ischemia of unknown origin should include an investigation to rule out asymptomatic Waldenström's macroglobulinemia.
Dynamic subcellular localization of isoforms of the folate pathway enzyme serine hydroxymethyltransferase (SHMT) through the erythrocytic cycle of Plasmodium falciparum
Authors: Read Martin , Müller Ingrid B , Mitchell Sarah L , Sims Paul FG , Hyde John E 
Published: December 2010

AbstractBackgroundThe folate pathway enzyme serine hydroxymethyltransferase (SHMT) converts serine to glycine and 5,10-methylenetetrahydrofolate and is essential for the acquisition of one-carbon units for subsequent transfer reactions. 5,10-methylenetetrahydrofolate is used by thymidylate synthase to convert dUMP to dTMP for DNA synthesis. InPlasmodium falciparuman enzymatically functional SHMT (PfSHMTc) and a related, apparently inactive isoform (PfSHMTm) are found, encoded by different genes. Here, patterns of localization of the two isoforms during the parasite erythrocytic cycle are investigated.MethodsPolyclonal antibodies were raised to PfSHMTc and PfSHMTm, and, together with specific markers for the mitochondrion and apicoplast, were employed in quantitative confocal fluorescence microscopy of blood-stage parasites.ResultsAs well as the expected cytoplasmic occupancy of PfSHMTc during all stages, localization into the mitochondrion and apicoplast occurred in a stage-specific manner. Although early trophozoites lacked visible organellar PfSHMTc, a significant percentage of parasites showed such fluorescence during the mid-to-late trophozoite and schizont stages. In the case of the mitochondrion, the majority of parasites in these stages at any given time showed no marked PfSHMTc fluorescence, suggesting that its occupancy of this organelle is of limited duration. PfSHMTm showed a distinctly more pronounced mitochondrial location through most of the erythrocytic cycle and GFP-tagging of its N-terminal region confirmed the predicted presence of a mitochondrial signal sequence. Within the apicoplast, a majority of mitotic schizonts showed a marked concentration of PfSHMTc, whose localization in this organelle was less restricted than for the mitochondrion and persisted from the late trophozoite to the post-mitotic stages. PfSHMTm showed a broadly similar distribution across the cycle, but with a distinctive punctate accumulation towards the ends of elongating apicoplasts. In very late post-mitotic schizonts, both PfSHMTc and PfSHMTm were concentrated in the central region of the parasite that becomes the residual body on erythrocyte lysis and merozoite release.ConclusionsBoth PfSHMTc and PfSHMTm show dynamic, stage-dependent localization among the different compartments of the parasite and sequence analysis suggests they may also reversibly associate with each other, a factor that may be critical to folate cofactor function, given the apparent lack of enzymic activity of PfSHMTm.
Quantitative PCR used to Assess HIV-1 Integration and 2-LTR Circle Formation in Human Macrophages, Peripheral Blood Lymphocytes and a CD4+ Cell Line
Authors: Friedrich Brian , Li Guangyu , Dziuba Natallia , Ferguson Monique R 
Published: December 2010

Abstract

Background
Integration is an intermediate step in the HIV life cycle and is defined as the insertion of HIV-1 proviral DNA into the host chromosome. If integration does not occur when HIV-1 cDNA enters the nucleus, it circularizes upon itself and forms a 2-LTR circle. Monitoring the level of integrated HIV-1 cDNA in different primary cell subsets is very important, particularly regarding the effect of HAART in HIV-1 infected individuals. Because of limitations of prior HIV-1 integration assays, there is limited data on the level of integration and 2-LTR circle formation in primary cell subsets, particularly in human monocyte-derived macrophages and peripheral blood lymphocytes (PBL).

Results
In this study, we utilized a well-defined, sensitive two-step quantitative real-time PCR method to detect HIV-1 integration as well as conventional real-time PCR to detect 2-LTR circle formation in human macrophages and PBL isolated from six different healthy donors, as well as U373 CD4+ cells by infecting with HIV-1SX (R5) or dual-tropic isolate HIV-189.6 (R5/X4) virus strains. We used the FDA-approved integrase inhibitor, raltegravir, to determine quantitative differences of integrated HIV viral cDNA in HIV-1 infected cells with and without raltegravir treatment. Our results show that integration and 2-LTR circle formation can be assessed in primary macrophages, PBL, and a CD4+ cell line by this method. Specifically, our results demonstrate that this two-step real-time PCR method can distinguish between HIV-1 integrated viral cDNA and non-integrated nuclear HIV-1 2-LTR circles caused by impaired integration with raltegravir-treatment. This further confirms that only integrated HIV-1 cDNA can be specifically amplified and quantified by two-step PCR without non-specifically detecting non-integrated viral cDNA.

Conclusion
These results consistently demonstrate that the well-established real-time PCR assays used are robust, sensitive and quantitative for the detection of HIV-1 integration and 2-LTR circle formation in physiologically relevant human macrophages and PBL using lab-adapted virus strains, instead of pseudovirus. With two-step real-time PCR, we show that unintegrated, nuclear HIV-1 cDNA is not detected in raltegravir-treated cells, while specific for only integrated HIV-1 cDNA in non-treated cells. These methods could be applied as a useful tool in further monitoring specific therapy in HIV-1 infected individuals.
Case report of intrafamilial variability in autosomal recessive centronuclear myopathy associated to a novel BIN1 stop mutation
Authors: Böhm Johann , Yiş Uluç , Ortaç Ragıp , Çakmakçı Handan , Kurul Semra Hız , Dirik Eray , Laporte Jocelyn 
Published: December 2010

Abstract
Centronuclear myopathies (CNM) describe a group of rare muscle diseases typically presenting an abnormal positioning of nuclei in muscle fibers. To date, three genes are known to be associated to a classical CNM phenotype. The X-linked neonatal form (XLCNM) is due to mutations in MTM1 and involves a severe and generalized muscle weakness at birth. The autosomal dominant form results from DNM2 mutations and has been described with early childhood and adult onset (ADCNM). Autosomal recessive centronuclear myopathy (ARCNM) is less characterized and has recently been associated to mutations in BIN1, encoding amphiphysin 2. Here we present the first clinical description of intrafamilal variability in two first-degree cousins with a novel BIN1 stop mutation. In addition to skeletal muscle defects, both patients have mild mental retardation and the more severely affected male also displays abnormal ventilation and cardiac arrhythmia, thus expanding the phenotypic spectrum of BIN1-related CNM to non skeletal muscle defects. We provide an up-to-date review of all previous cases with ARCNM and BIN1 mutations.
Global analysis of phase locking in gene expression during cell cycle: the potential in network modeling
Authors: Gao Shouguo , Hartman IV John L , Carter Justin L , Hessner Martin J , Wang Xujing 
Published: December 2010

Abstract

Background
In nonlinear dynamic systems, synchrony through oscillation and frequency modulation is a general control strategy to coordinate multiple modules in response to external signals. Conversely, the synchrony information can be utilized to infer interaction. Increasing evidence suggests that frequency modulation is also common in transcription regulation.

Results
In this study, we investigate the potential of phase locking analysis, a technique to study the synchrony patterns, in the transcription network modeling of time course gene expression data. Using the yeast cell cycle data, we show that significant phase locking exists between transcription factors and their targets, between gene pairs with prior evidence of physical or genetic interactions, and among cell cycle genes. When compared with simple correlation we found that the phase locking metric can identify gene pairs that interact with each other more efficiently. In addition, it can automatically address issues of arbitrary time lags or different dynamic time scales in different genes, without the need for alignment. Interestingly, many of the phase locked gene pairs exhibit higher order than 1:1 locking, and significant phase lags with respect to each other. Based on these findings we propose a new phase locking metric for network reconstruction using time course gene expression data. We show that it is efficient at identifying network modules of focused biological themes that are important to cell cycle regulation.

Conclusions
Our result demonstrates the potential of phase locking analysis in transcription network modeling. It also suggests the importance of understanding the dynamics underlying the gene expression patterns.
An experimentally validated heat transfer model for thermal management design in polymer electrolyte membrane fuel cells
Authors: Matian M , Marquis A , Brett D , Brandon N 
Published: December 2010

The temperature distribution in polymer electrolyte membrane fuel cells (PEMFCs) plays a vital role in defining the overall efficiency and in ensuring the delivery of optimum performance, and understanding the heat transfer taking place is essential for the design of effective thermal and water management systems. This article describes a simple model, validated against experiment, which can be used to investigate the factors such as bipolar plate design, materials of construction, and the external effects of forced convection such as cooling fans and natural convection. The model employs computational fluid dynamics to account for the reactant flows in composite graphite plates and heat distribution within the stack, while convective heat transfer from the external surface of the fuel cell is treated using well-known heat transfer correlations. The computational model was validated using a novel fuel cell analogue composed of an electrically controlled heating plate to simulate the heat generated by the membrane electrode assembly and instrumented with 14 calibrated thermocouples. The model showed good agreement with the experiment over a wide range of gas flowrates, both in terms of local temperature distribution and overall energy balance. This suggests that the novel experimental methodology reported here could be used to support the design of bipolar plates for optimum heat transfer.