bluuebunny/crossref_metadata_2025 huggingface dataset:
Four-Decade Maintenance of Analgesia with Percutaneous Cordotomy
Authors: Collins Kelly L. , Taren James A. , Patil Parag G.
Published: July 2012

The management of severe, medically intractable pain is a significant challenge for neurosurgeons and pain management physicians. An existing technique that can effectively alleviate contralateral chronic pain is cordotomy, interruption of the lateral spinothalamic tract of the spinal cord. Since 1912, cordotomy has evolved from a relatively morbid open surgical procedure to a percutaneous radiofrequency procedure with low morbidity. However, since cordotomy is utilized primarily in cancer pain patients, long-term patient follow-up is rare, and the potential duration of analgesia following cordotomy is not known. Here we describe a case with a 41-year follow-up of percutaneous cordotomy for noncancer pain that resulted in over 35 years of complete analgesia, the longest recorded in the literature to date. This case demonstrates that percutaneous cordotomy can provide long-lasting, complete analgesia in some patients and merits continuation as a part of the neurosurgical arsenal of pain therapies.
Descriptive Epidemiology of Pediatric Intracranial Neoplasms in Egypt
Authors: El-Gaidi Mohamed Ali
Published: July 2012

Objective: The characteristics of 451 Egyptian children (aged 0–14 years) with primary intracranial neoplasms were investigated for demographic, clinical, topographical and pathological features using the most recent 2007 Classification of Central Nervous System Tumors. Patients and Methods: This was a retrospective study performed in the Departments of Pediatric Neurosurgery of the Cairo University Hospitals from 2005 to 2008. Results: There was a slight male predominance (51.4%) observed in our study, and the most affected age group was 5–9 years old (43.2%). Most of the tumors were confined to a single compartment (infratentorial in 49.7%, supratentorial in 46.6%), while 3.8% of the tumors involved multiple compartments. The most common intracranial tumors were astrocytomas (35%), medulloblastomas (18.8%), craniopharyngiomas (11.3%) and ependymomas (10%). Pilocytic astrocytomas constituted 55% of all astrocytomas and 19.3% of all brain tumors, only slightly ahead of medulloblastomas. Less common types were primitive neuroectodermal tumors (2.7%), followed by meningiomas, germ cell tumors and choroid plexus tumors (2.4% each). According to the International Classification of Diseases for Oncology Coding (ICD-O-4), benign, borderline and malignant tumors constituted 7.54, 36.14 and 56.32%, respectively. Conclusion: The characteristics of pediatric intracranial tumors in Egypt are generally similar to those reported in the literature, with only minor differences.
Impact of Histopathology on the Outcome of D1/D2 Gastrectomies with R0 Resection
Authors: Uslu Adam , Bati Hasan , Postaci Hakan , Nart Ahmet , Eliyatkin Nukhet , Yetıs Halit , Corumlu Baris , Aykas Ahmet , Zengel Baha
Published: July 2012

Aims: The primary objective of this study was to clarify the influence of histotype on the outcome of D1/D2 gastrectomized patients with pathologically proven R0 resection. The secondary objective was to demonstrate overall survival (OS), disease-free survival (DFS), and locoregional recurrence rates following standard curative surgery. Patients and Methods: All patients had either pure signet-ring cell carcinoma (SRCC)/poorly differentiated adenocarcinoma (PDC) or moderately differentiated adenocarcinoma (MDC) of the stomach, preoperative radiologic evidence of locoregional disease, and no history of neoadjuvant therapy. Standards of surgical treatment were essentially based on the guidelines of the Japanese Research Society for the Study of Gastric Cancer. Results: Between October 2003 and August 2010, seventy-eight patients were enrolled. Twenty-three patients underwent D1 dissection and 55 underwent D2 dissection. The OS and DFS rates were 33.2 ± 5.9 months versus 31.5 ± 4.3 months (p = 0.81) and 28.9 ± 5.6 months vs. 29.3 ± 4.4 months (p = 0.96) in the MDC and SRCC/PDC groups, respectively. Neither the extent of the operation (D1 vs. D2, p = 0.79) nor the histopathologic subtype of the primary tumor (MDC vs. SRCC/PDC, p = 0.91) influenced the OS and DFS. Multivariate logistic regression analysis disclosed pathologic stage (pTNM) as the only significant prognostic determinant of OS (p = 0.007) and DFS (p = 0.0003). Conclusion: Properly performed D1 and D2 dissection in our series resulted in a notable (6.4%) locoregional failure rate. In spite of the satisfactory locoregional control achieved by D1 and D2, there was no improvement in the survival figures of stage IIIA-B and IV gastric cancer patients. The histopathologic subtype of the primary tumor disclosed merely a statistical trend on the outcome measures of gastric cancer after curative surgery.
Intraoperative Facial Electromyography and Brainstem Auditory Evoked Potential Findings in Microvascular Decompression for Hemifacial Spasm: Correlation with Postoperative Delayed Facial Palsy
Authors: Kim Hee Jin , Park Young Seok , Ryu Ju Seok , Huh Ryoong , Han Inbo , Shin Dong Ah , Kim Tae Gon , Cho Kyung Gi , Chung Sang-Sup
Published: July 2012

Background: Delayed facial palsy (DFP) after microvascular decompression (MVD) in patients with hemifacial spasm (HFS) is not uncommon, but the cause remains unknown. Objectives: To assess whether intraoperative electromyography (EMG) and brainstem auditory evoked potential (BAEP) can predict DFP after MVD. Methods: Between September 2009 and February 2011 we examined 86 patients, 9 of whom (10.4%) developed DFP after MVD on the same side. All patients underwent MVD and were followed-up for a median period of 13 months (range 6–22). We retrospectively examined intraoperative facial EMG and BAEP findings using our MVD patients’ registry. We excluded secondary HFS and immediate postoperative facial palsy after MVD in this study. We assessed the prevalence and clinical characteristics of DFP and compared EMG and BAEP findings between DFP and non-DFP groups. Results: All patients recovered completely, with a mean time to recovery of 37.8 days (range 22–57). There were no significant differences between DFP and non-DFP patients in terms of the amplitude and latency of intraoperative EMG and BAEP. Conclusion: The usefulness of intraoperative facial EMG and BAEP is limited and cannot predict DFP after MVD for HFS. We speculate that DFP after MVD is not associated with permanent nerve damage according to the EMG findings.
Giant Encephalocele: A Study of 14 Patients
Authors: Mahapatra A.K.
Published: July 2012

Background: Giant encephalocele is a rare condition and few published reports are available in the English literature. It is a challenge to neurosurgeons, even today. This series consists of 14 patients with giant encephaloceles treated at our institute. Material and Observation: Over a period of 8 years, from 2002 to 2009, 110 patients with encephaloceles were managed at our institute. Amongst them, 14 were children with giant encephaloceles. All patients had CT/MRI or both prior to surgery, and all were operated upon. Four patients were neonates, under 1 month of age, and 9/14 patients (64%) were under 3 months. The youngest child was a newborn baby aged 2 days. Except for 1 with an anterior encephalocele, the rest were patients with occipital encephaloceles. A CT scan was performed on 5 and an MRI on 1 patient. Both CT and MRI scans were performed on the other 8 patients. MRI/CT showed hydrocephalus in 10/14 patients. Of these, 7 required ventriculoperitoneal (VP) shunt, and the remaining 3 with mild to moderate hydrocephalus did not. Of the 7 patients who underwent VP shunt, 5 had a shunt during the encephalocele repair and 2 had a postoperative shunt for increasing hydrocephalus. Results: Other associated anomalies recorded were acquired Chiari malformation in 3 patients, secondary craniostenosis with microcephaly in 5, and syringomyelia in 1 patient. All the patients underwent repair of encephalocele and 4 had suturectomy of coronal suture for the secondary craniostenosis. There were 2 postoperative deaths due to hypothermia. Among the 12 surviving patients, 9 had a good outcome and 3 had poor mental development. The present study shows overall good outcomes in 9/14 (66%) patients.
Safety Verification Trials of mFOLFIRI and Sequential IRIS + Bevacizumab as First- or Second-Line Therapies for Metastatic Colorectal Cancer in Japanese Patients
Authors: Kato Shunsuke , Andoh Hideaki , Gamoh Makio , Yamaguchi Takuhiro , Murakawa Yasuko , Shimodaira Hideki , Takahashi Shin , Mori Takahiro , Ohori Hisatsugu , Maeda Shun-ichi , Suzuki Takao , Kato Satoshi , Akiyama Shoko , Sasaki Yuka , Yoshioka Takashi , Ishioka Chikashi ,   on behalf of Tohoku Clinical Oncology Research and Education
Published: July 2012

Objective: S-1 is effective in sequential combination with irinotecan (IRIS) in treating metastatic colorectal cancer. We conducted a randomized phase II trial of modified leucovorin, fluorouracil and irinotecan (mFOLFIRI) + bevacizumab and sequential IRIS + bevacizumab as first- or second-line therapies. Methods: Sixty metastatic colorectal cancer patients were randomly assigned to receive mFOLFIRI + bevacizumab or sequential IRIS + bevacizumab (7.5 mg/kg of bevacizumab and 150 mg/m2 of irinitecan, and 80 mg/m2/day of S-1 orally from day 3 until day 16 as a 3-week course). The primary endpoint was the safety of each method until week 12, with the secondary endpoint being the comparison of the safety and efficacy of the two methods. Results: The safety of the two treatments was comparable, except that G3 anorexia and diarrhoea were less frequent with sequential IRIS + bevacizumab. The overall response rate was 62% [95% confidence interval (CI) 40.1–79.8] versus 72% (95% CI 50.6–86.2), and progression-free survival was 324 days (95% CI 247–475) versus 345 days (95% CI 312–594) with mFOLFIRI + bevacizumab versus IRIS + bevacizumab, respectively. Conclusion: Sequential IRIS + bevacizumab is a safe and effective method of systemic chemotherapy against metastatic colorectal cancer and is compatible with mFOLFIRI + bevacizumab.
Relationship between Immunological Parameters and the Severity of Neutropenia and Effect of Enteral Nutrition on Immune Status during Neoadjuvant Chemotherapy on Patients with Advanced Esophageal Cancer
Authors: Motoori Masaaki , Yano Masahiko , Yasuda Takushi , Miyata Hiroshi , Peng Ying Feng , Yamasaki Makoto , Shiraishi Osamu , Tanaka Koji , Ishikawa Osamu , Shiozaki Hitoshi , Doki Yuichiro
Published: July 2012

Objectives: Chemotherapy may cause various toxicities as well as impair immunological function. However, little is known about the relationship between toxicities and immunological parameters or the effect of enteral nutrition (EN) on immunological status during chemotherapy. Methods: 91 patients who received neoadjuvant chemotherapy (NACT) for esophageal cancer were randomly assigned to receive either EN or parenteral nutrition (PN). Immunological parameters, including total lymphocyte count (TLC), type 1 and type 2 CD4-positive T cells (Th1/Th2) balance, human leukocyte antigen (HLA)-DR expression on monocytes, natural killer cell activity, and phytohemagglutinin-stimulated lymphocyte proliferation were measured at baseline and day 14 of the first chemotherapy cycle. Results: In the PN group, patients with grade 3–4 neutropenia showed significantly lower TLC, HLA-DR expression, and Th1/Th2 balance at day 14 compared to those with grade 0–2 neutropenia. Among pretherapeutic factors, Th1/Th2 balance was the only factor significantly associated with the severity of neutropenia. Concerning the comparison of immunological parameters between the EN and PN groups, HLA-DR expression at day 14 was significantly higher in the EN group. Conclusions: Baseline Th1/Th2 balance predicted the severity of neutropenia, and EN significantly reduced the decline of monocyte HLA-DR expression in patients with esophageal cancer receiving NACT.
New Methods toward Minimizing the Slow Speed Bias Associated with Atmospheric Motion Vectors
Authors: Bresky Wayne C. , Daniels Jaime M. , Bailey Andrew A. , Wanzong Steven T.
Published: July 2012

Comparisons between satellite-derived winds and collocated rawinsonde observations often show a pronounced slow speed bias at mid- and upper levels of the atmosphere. A leading cause of the slow speed bias is the improper assignment of the tracer to a height that is too high in the atmosphere. Height errors alone cannot fully explain the slow bias, however. Another factor influencing the speed bias is the size of the target window used in the tracking step. Tracking with a large target window can cause excessive averaging to occur and a smoothing of the instantaneous wind field. Conversely, if too small a window is specified, there is an increased risk of finding a false match. The authors have developed a new “nested tracking” approach that isolates the dominant local motion within a cloud scene and minimizes the smoothing of the motion estimate. A major advantage of the new approach is the ability to identify which pixels within the cloud scene are contributing to the tracking solution. Knowing which pixels contribute to the dominant motion allows for a more representative height to be derived, thereby directly linking the height assignment to the tracking process, which is an important goal for producers of global atmospheric motion vector (AMV) data. When compared with equivalent rawinsondes, the AMVs derived with the new approach show a considerable improvement in the speed bias and root-mean-square error over a control set of AMVs derived with more-conventional methods.
Practical and Intrinsic Predictability of Severe and Convective Weather at the Mesoscales
Authors: Melhauser Christopher , Zhang Fuqing
Published: July 2012

This study explores both the practical and intrinsic predictability of severe convective weather at the mesoscales using convection-permitting ensemble simulations of a squall line and bow echo event during the Bow Echo and Mesoscale Convective Vortex (MCV) Experiment (BAMEX) on 9–10 June 2003. Although most ensemble members—initialized with realistic initial condition uncertainties smaller than the NCEP Global Forecast System Final Analysis (GFS FNL) using an ensemble Kalman filter—forecast broad areas of severe convection, there is a large variability of forecast performance among different members, highlighting the limit of practical predictability. In general, the best-performing members tend to have a stronger upper-level trough and associated surface low, producing a more conducive environment for strong long-lived squall lines and bow echoes, once triggered. The divergence in development is a combination of a dislocation of the upper-level trough, surface low with corresponding marginal environmental differences between developing and nondeveloping members, and cold pool evolution by deep convection prior to squall line formation. To further explore the intrinsic predictability of the storm, a sequence of sensitivity experiments was performed with the initial condition differences decreased to nearly an order of magnitude smaller than typical analysis and observation errors. The ensemble forecast and additional sensitivity experiments demonstrate that this storm has a limited practical predictability, which may be further improved with more accurate initial conditions. However, it is possible that the true storm could be near the point of bifurcation, where predictability is intrinsically limited. The limits of both practical and intrinsic predictability highlight the need for probabilistic and ensemble forecasts for severe weather prediction.
A Role of the Yellow and East China Seas in the Development of Extratropical Cyclones in Winter
Authors: Isobe Atsuhiko , Kako Shin’ichiro
Published: July 2012

To investigate whether the relatively warm Yellow and East China Seas play an active role in the deepening of extratropical cyclones over East Asia during winter, surface wind vectors downloaded from the Quick Scatterometer (QuikSCAT) website are used to compute the standard deviation of surface vorticity at ¼° resolution. In addition, a regional numerical atmospheric model is adopted to find atmospheric and/or oceanic conditions favorable for development of extratropical cyclones over the study area. These satellite-derived and modeled vorticity fields demonstrate that, on average, extratropical cyclone activity is moderate over the warm Yellow and East China Seas. This is because enhanced lower-level baroclinicity over these ocean areas is transferred as far as the shelf break of the East China Sea by strong northwesterly surface winds. Based on the numerical model results, the weak northwesterly surface wind condition is required for enhancing lower-level baroclinicity over the Yellow and East China Seas. This baroclinicity may contribute to enhancing cyclone development near Japan, with a simultaneous increase of lower-level baroclinicity over the Sea of Japan.
Global Atmospheric Evaporative Demand over Land from 1973 to 2008
Authors: Wang Kaicun , Dickinson Robert E. , Liang Shunlin
Published: July 2012

Pan evaporation (EP), an index of atmospheric evaporative demand, has been widely reported to have weakened in the past decades. However, its interpretation remains controversial because EP observations are not globally available and observations of one of its key controls, surface incident solar radiation Rs, are even less available. Using global-distributed Rs from both direct measurements (available through the Global Energy Balance Archive) and derived from sunshine duration, the authors calculated the potential evaporation from 1982 to 2008 from approximately 1300 stations. The findings herein show that the contribution of water vapor pressure deficit (VPD) to monthly variability of EP is much larger than that of other controlling factors, of Rs, wind speed (WS), and air temperature Ta. The trend of the aerodynamic component of EP, which includes contributions of VPD, WS, and Ta, accounted for 86% of the long-term trend of EP. The aerodynamic component was then calculated from 4250 globally distributed stations and showed a negligible averaged trend from 1973 to 2008 because the reduction in WS canceled out the impact of the elevated VPD. The long-term trend of WS dominates the long-term trend of the aerodynamic component of EP at the 4250 stations. Atmospheric evaporative demand increased in most arid and semiarid areas, indicating a decrease in water availability in those areas.
Influence of the Madden–Julian Oscillation and Intraseasonal Waves on Surface Wind and Convection of the Tropical Atlantic Ocean
Authors: Yu Wei , Han Weiqing , Gochis David
Published: July 2012

Atmospheric intraseasonal variability in the tropical Atlantic is analyzed using satellite winds, outgoing longwave radiation (OLR), and reanalysis products during 2000–08. The analyses focus on assessing the effects of dominant intraseasonal atmospheric convective processes, the Madden–Julian oscillation (MJO), and Rossby waves on surface wind and convection of the tropical Atlantic Ocean and African monsoon area. The results show that contribution from each process varies in different regions. In general, the MJO events dominate the westward-propagating Rossby waves in affecting strong convection in the African monsoon region. The Rossby waves, however, have larger contributions to convection in the western Atlantic Ocean. Both the westward- and eastward-propagating signals contribute approximately equally in the central Atlantic basin. The effects of intraseasonal signals have evident seasonality. Both convection amplitude and the number of strong convective events associated with the MJO are larger during November–April than during May–October in all regions. Convection associated with Rossby wave events is stronger during November–April for all regions, and the numbers of Rossby wave events are higher during November–April than during May–October in the African monsoon region, and are comparable for the two seasons in the western and central Atlantic basins. Of particular interest is that the MJOs originating from the Indo-Pacific Ocean can be enhanced over the tropical Atlantic Ocean while they propagate eastward, amplifying their impacts on the African monsoon. On the other hand, Rossby waves can originate either in the eastern equatorial Atlantic or West African monsoon region, and some can strengthen while they propagate westward, affecting surface winds and convection in the western Atlantic and Central American regions.
Evaluation of Microphysics Parameterization for Convective Clouds in the NCAR Community Atmosphere Model CAM5
Authors: Song Xiaoliang , Zhang Guang J. , Li J.-L. F.
Published: July 2012

A physically based two-moment microphysics parameterization scheme for convective clouds is implemented in the NCAR Community Atmosphere Model version 5 (CAM5) to improve the representation of convective clouds and their interaction with large-scale clouds and aerosols. The explicit treatment of mass mixing ratio and number concentration of cloud and precipitation particles enables the scheme to account for the impact of aerosols on convection. The scheme is linked to aerosols through cloud droplet activation and ice nucleation processes and to stratiform cloud parameterization through convective detrainment of cloud liquid/ice water content (LWC/IWC) and droplet/crystal number concentration (DNC/CNC). A 5-yr simulation with the new convective microphysics scheme shows that both cloud LWC/IWC and DNC/CNC are in good agreement with observations, indicating the scheme describes microphysical processes in convection well. Moreover, the microphysics scheme is able to represent the aerosol effects on convective clouds such as the suppression of warm rain formation and enhancement of freezing when aerosol loading is increased. With more realistic simulations of convective cloud microphysical properties and their detrainment, the mid- and low-level cloud fraction is increased significantly over the ITCZ–southern Pacific convergence zone (SPCZ) and subtropical oceans, making it much closer to the observations. Correspondingly, the serious negative bias in cloud liquid water path over subtropical oceans observed in the standard CAM5 is reduced markedly. The large-scale precipitation is increased and precipitation distribution is improved as well. The long-standing precipitation bias in the western Pacific is significantly alleviated because of microphysics–thermodynamics feedbacks.
The Interannual Variability of Summer Upper-Tropospheric Temperature over East Asia
Authors: Zhang Lixia , Zhou Tianjun
Published: July 2012

By using 55-yr NCEP–NCAR reanalysis data, two dominant interannual variability modes of summer upper-tropospheric (500–200 hPa) temperature over East Asia are identified. The first empirical orthogonal function (EOF1) mode in its positive sign features a monopole cooling anomaly, while the second mode (EOF2) features a meridional dipole mode, with the positive (negative) center located south (north) of 35°N. The EOF1 (EOF2) mode is associated with ENSO developing (decaying) summers. They are the result of dynamical teleconnections remotely induced by ENSO and local moist processes. During the El Niño developing summer, the Indian summer monsoon precipitation decreases and forces the Silk Road teleconnection pattern at 200 hPa, featuring an anomalous cyclone over the East Asian continent. Coupled with the anomalous northerly wind in eastern China at 850 hPa, rainfall over north (south) China is suppressed (enhanced). The anomalous cyclone in the upper troposphere, associated vertical motion, and precipitation contribute to the heat and vorticity balance and maintain the monopole cooling. In the El Niño decaying summer, driven by the combined effects of a local SST anomaly and remote warm SST anomaly forcing from the Indian Ocean, precipitation is reduced over the western Pacific Ocean. Less latent heat is released and forces the Pacific–Japan teleconnection pattern along the East Asian continent, inducing a tripolar rainfall anomaly over East Asia. The tripolar precipitation and vertical motion anomalies and the zonal extended cyclonic anomaly in the upper troposphere provide the heating and momentum flux balance and maintain the temperature anomaly pattern during the ENSO decaying summer.
Observations of Climate Feedbacks over 2000–10 and Comparisons to Climate Models*
Authors: Dessler A. E.
Published: July 2012

Feedbacks in response to climate variations during the period 2000–10 have been calculated using reanalysis meteorological fields and top-of-atmosphere flux measurements. Over this period, the climate was stabilized by a strongly negative temperature feedback (~−3 W m−2 K−1); climate variations were also amplified by a strong positive water vapor feedback (~+1.2 W m−2 K−1) and smaller positive albedo and cloud feedbacks (~+0.3 and +0.5 W m−2 K−1, respectively). These observations are compared to two climate model ensembles, one dominated by internal variability (the control ensemble) and the other dominated by long-term global warming (the A1B ensemble). The control ensemble produces global average feedbacks that agree within uncertainties with the observations, as well as producing similar spatial patterns. The most significant discrepancy was in the spatial pattern for the total (shortwave + longwave) cloud feedback. Feedbacks calculated from the A1B ensemble show a stronger negative temperature feedback (due to a stronger lapse-rate feedback), but that is cancelled by a stronger positive water vapor feedback. The feedbacks in the A1B ensemble tend to be more smoothly distributed in space, which is consistent with the differences between El Niño–Southern Oscillation (ENSO) climate variations and long-term global warming. The sum of all of the feedbacks, sometimes referred to as the thermal damping rate, is −1.15 ± 0.88 W m−2 K−1 in the observations and −0.60 ± 0.37 W m−2 K−1 in the control ensemble. Within the control ensemble, models that more accurately simulate ENSO tend to produce thermal damping rates closer to the observations. The A1B ensemble average thermal damping rate is −1.26 ± 0.45 W m−2 K−1.
Trends in Summer Rainfall over China Associated with the Tibetan Plateau Sensible Heat Source during 1980–2008
Authors: Duan Anmin , Wang Meirong , Lei Yonghui , Cui Yangfan
Published: July 2012

The impacts of the thermal forcing over the Tibetan Plateau (TP) in spring on changes in summer rainfall in China are investigated using historical records from the period between 1980 and 2008. The spring sensible heat (SH) flux and snow depth over the TP both decreased over this time period, although the trend in SH was more significant than that in snow depth. The similarity between patterns of precipitation trends over China and corresponding patterns of regression coefficients on the leading mode of spring SH change over the TP demonstrates the distinct contribution of changes in TP SH during spring. Enhanced precipitation in southern China was accompanied by increases in heavy rainfall, precipitation intensity, and the frequency of precipitation events, while reduced precipitation in northern China and northeastern China was primarily associated with decreases in the frequency of precipitation events. Further analysis using observational data and numerical simulations reveals that the reductions in SH over the TP have weakened the monsoon circulation and postponed the seasonal reversal of the land–sea thermal contrast in East Asia. In addition, the positive spring SH anomaly may generate a stronger summer atmospheric heat source over the TP due to the positive feedback between diabatic heating and local circulation.
Dynamic mechanical thermal analysis and dielectric thermal analysis of siloxane rubber-based composites filled with carbon black
Authors: Al-Hartomy Omar A , Ibrahim MA , Al-Ghamdi Ahmed , Dishovsky Nikolay , Ivanov Milcho , Mihaylov Mihail , El-Tantawy Farid
Published: July 2012

Siloxane rubber-based composites filled with furnace carbon black N 220 at various concentrations were investigated bydynamic mechanical thermal analysis and dielectric thermal analysis. It was found that in the temperature interval from−30°C to 100°C the increase in the amount of carbon black results in the increase in the storage modulus ( E′) values, as well as those of the mechanical loss angle tangent (tan δ). The decrease in E′ and the increase in tan δ in the interval from −40°C to −30°C was due to the process of the melting of the crystal structure of the siloxane rubber, formed during the cooling of the tested samples. Dielectric thermal analysis showed that the increase in the amount of carbon black lead to obtaining of vulcanizates with higher dielectric permittivity ( ε′), whose values decrease with the increase of frequency. The research that was carried out showed that with the siloxane rubber-based composites the percolation threshold was reached when the concentration of carbon black was 20 wt%.
A utilization-focused approach to contribution analysis
Authors: Patton Michael Quinn
Published: July 2012

Utilization-focused evaluation involves identifying and working with primary intended users to design and interpret an evaluation. This includes the process of working with primary intended users to render judgments about the extent to which the preponderance of evidence supports a meaningful and useful conclusion about degree to which an intervention has affected observed outcomes and impacts. This is the essence of contribution analysis. Two in-depth examples illustrate this process.
Making sense of impact: A methodological framework for assessing the impact of prizes
Authors: Vaessen Jos , Raimondo Estelle
Published: July 2012

In recent years, debates on impact evaluation of development cooperation have flourished. There has been a marked increase in statistical impact evaluation exercises, most notably randomized experiments, and at the same time, many evaluations with a focus on impact have relied on alternative methodological approaches. The diversity in methodological approaches can be explained by differences in epistemology, characteristics of the evaluand and of the evaluation context. Broadly speaking there are two approaches: impact evaluations that rely on statistical design and/or multivariate analysis with statistical controls as a basis for attribution; and impact evaluations relying on systematic argumentation guided by some type of causal theory of change. Contribution analysis is an example of a heuristic framework that fits in the latter category and this article relates this approach to an evaluation of prizes awarded by UNESCO (The United Nations Educational, Scientific and Cultural Organization). It discusses the intervention logic underlying UNESCO prizes and the corresponding framework for empirical assessment that in part reflects the institutional context and constraints. Finally, we discuss how the evaluation can provide the basis for a full-fledged impact evaluation of a prize using contribution analysis.
Contribution analysis: Coming of age?
Authors: Mayne John
Published: July 2012

In this introductory article, a brief history and introduction to contribution analysis is provided to lay the stage for the articles that follow. At the heart of contribution analysis is the aim to be able to make credible causal claims about the contribution an intervention is making to observed results. The key role that theories of change play is noted, and what a useful theory of change ought to contain is discussed. The article then makes a link between the philosophical discussions on causality and contribution analysis through a discussion of contributory causes. It is argued that such causes, which on their own are neither necessary nor sufficient, represent the kind of contribution role that many interventions play: where there are a number of other influencing events and conditions at work in addition to the intervention of interest. Contribution analysis is an approach to confirming that an intervention is a contributory cause.
Changing Political Landscapes for Latinos in America
Authors: Casellas Jason P. , Ibarra Joanne D.
Published: July 2012

The increased demographic presence of Latino individuals has gradually resulted in growing political influence and representation. This growing presence and influence has altered the American political landscape, drawing sudden attention among scholars, the media, and political pundits. This article investigates four aspects of the growing influence of Latino/a individuals in the American political system.
The paracrine effect of exogenous growth hormone alleviates dysmorphogenesis caused by tbx5 deficiency in zebrafish (Danio rerio) embryos
Authors: Tsai Tzu-Chun , Lu Jen-Kann , Choo Sie-Lin , Yeh Shu-Yu , Tang Ren-Bing , Lee Hsin-Yu , Lu Jen-Her
Published: July 2012

Background

Dysmorphogenesis and multiple organ defects are well known in zebrafish (Danio rerio) embryos with T-box transcription factor 5 (tbx5) deficiencies, mimicking human Holt-Oram syndrome.

Methods

Using an oligonucleotide-based microarray analysis to study the expression of special genes in tbx5 morphants, we demonstrated that GH and some GH-related genes were markedly downregulated. Zebrafish embryos microinjected with tbx5-morpholino (MO) antisense RNA and mismatched antisense RNA in the 1-cell stage served as controls, while zebrafish embryos co-injected with exogenous growth hormone (GH) concomitant with tbx5-MO comprised the treatment group.

Results

The attenuating effects of GH in tbx5-MO knockdown embryos were quantified and observed at 24, 30, 48, 72, and 96 h post-fertilization. Though the understanding of mechanisms involving GH in the tbx5 functioning complex is limited, exogenous GH supplied to tbx5 knockdown zebrafish embryos is able to enhance the expression of downstream mediators in the GH and insulin-like growth factor (IGF)-1 pathway, including igf1, ghra, and ghrb, and signal transductors (erk1, akt2), and eventually to correct dysmorphogenesis in various organs including the heart and pectoral fins. Supplementary GH also reduced apoptosis as determined by a TUNEL assay and decreased the expression of apoptosis-related genes and proteins (bcl2 and bad) according to semiquantitative reverse-transcription polymerase chain reaction and immunohistochemical analysis, respectively, as well as improving cell cycle-related genes (p27 and cdk2) and cardiomyogenetic genes (amhc, vmhc, and cmlc2).

Conclusions

Based on our results, tbx5 knockdown causes a pseudo GH deficiency in zebrafish during early embryonic stages, and supplementation of exogenous GH can partially restore dysmorphogenesis, apoptosis, cell growth inhibition, and abnormal cardiomyogenesis in tbx5 knockdown zebrafish in a paracrine manner.
Role of gamma-delta T cells in host response against Staphylococcus aureus-induced pneumonia
Authors: Cheng Ping , Liu Tao , Zhou Wei-Ying , Zhuang Yuan , Peng Liu-sheng , Zhang Jin-yu , Yin Zhi-Nan , Mao Xu-hu , Guo Gang , Shi Yun , Zou Quan-ming
Published: July 2012

Background

Staphylococcus aureusis the major cause of hospital-acquired and community-acquired pneumonia. Host defense toS.aureusinfection is largely mediated by the innate immune system. γδ T cells play an important role in innate immunity to many infectious diseases. However, less is known about the role of these cells duringS.aureus-induced pneumonia. In this study, we examined the response and the role of γδ T cells to pulmonaryS.aureusinfection.

Results

Mice infected withS. aureusintranasally showed rapid γδ T cells accumulation in the lung. Deficiency of γδ T cells led to attenuated bacterial clearance and less tissue damage in lung compared with WT mice. Moreover, TCR-δ−/−mice exhibited impaired neutrophil recruitment and reduced cytokine production at the site of infection. The γδ T cells in response to pulmonaryS. aureusinfection mainly secreted IL-17 and γδ T cells deficiency reduced IL-17 production, which might regulate the production of neutrophil-inducing cytokine/chemokine in theS. aureus-infected lungs.

Conclusions

Accumulation of γδ T cells in the lungs toS. aureusinfection is beneficial for bacteria clearance and also contributes to the tissue damage. These cells were the primary source of IL-17, which might influence the recruitment of neutrophils at the early stage of infection.
A multi-perspective cost-effectiveness analysis comparing rivaroxaban with enoxaparin sodium for thromboprophylaxis after total hip and knee replacement in the German healthcare setting
Authors: Zindel Sonja , Stock Stephanie , Müller Dirk , Stollenwerk Björn
Published: July 2012

Background

Patients undergoing major orthopaedic surgery (MOS), such as total hip (THR) or total knee replacement (TKR), are at high risk of developing venous thromboembolism (VTE). For thromboembolism prophylaxis, the oral anticoagulant rivaroxaban has recently been included in the German diagnosis related group (DRG) system. However, the cost-effectiveness of rivaroxaban is still unclear from both the German statutory health insurance (SHI) and the German hospital perspective.

Objectives

To assess the cost-effectiveness of rivaroxaban from the German statutory health insurance (SHI) perspective and to analyse financial incentives from the German hospital perspective.

Methods

Based on data from the RECORD trials and German cost data, a decision tree was built. The model was run for two settings (THR and TKR) and two perspectives (SHI and hospital) per setting.

Results

Prophylaxis with rivaroxaban reduces VTE events (0.02 events per person treated after TKR; 0.007 after THR) compared with enoxaparin. From the SHI perspective, prophylaxis with rivaroxaban after TKR is cost saving (€27.3 saving per patient treated). However, the cost-effectiveness after THR (€17.8 cost per person) remains unclear because of stochastic uncertainty. From the hospital perspective, for given DRGs, the hospital profit will decrease through the use of rivaroxaban by €20.6 (TKR) and €31.8 (THR) per case respectively.

Conclusions

Based on our findings, including rivaroxaban for reimbursement in the German DRG system seems reasonable. Yet, adequate incentives for German hospitals to use rivaroxaban are still lacking.
Inhibition of CD200R1 expression by C/EBP beta in reactive microglial cells
Authors: Dentesano Guido , Straccia Marco , Ejarque-Ortiz Aroa , Tusell Josep M , Serratosa Joan , Saura Josep , Solà Carme
Published: July 2012

Background

In physiological conditions, it is postulated that neurons control microglial reactivity through a series of inhibitory mechanisms, involving either cell contact-dependent, soluble-factor-dependent or neurotransmitter-associated pathways. In the current study, we focus on CD200R1, a microglial receptor involved in one of these cell contact-dependent mechanisms. CD200R1 activation by its ligand, CD200 (mainly expressed by neurons in the central nervous system),is postulated to inhibit the pro-inflammatory phenotype of microglial cells, while alterations in CD200-CD200R1 signalling potentiate this phenotype. Little is known about the regulation of CD200R1 expression in microglia or possible alterations in the presence of pro-inflammatory stimuli.

Methods

Murine primary microglial cultures, mixed glial cultures from wild-type and CCAAT/enhancer binding protein β (C/EBPβ)-deficient mice, and the BV2 murine cell line overexpressing C/EBPβ were used to study the involvement of C/EBPβ transcription factor in the regulation of CD200R1 expression in response to a proinflammatory stimulus (lipopolysaccharide (LPS)). Binding of C/EBPβ to the CD200R1 promoter was determined by quantitative chromatin immunoprecipitation (qChIP). The involvement of histone deacetylase 1 in the control of CD200R1 expression by C/EBPβ was also determined by co-immunoprecipitation and qChIP.

Results

LPS treatment induced a decrease in CD200R1 mRNA and protein expression in microglial cells, an effect that was not observed in the absence of C/EBPβ. C/EBPβ overexpression in BV2 cells resulted in a decrease in basal CD200R1 mRNA and protein expression. In addition, C/EBPβ binding to the CD200R1 promoter was observed in LPS-treated but not in control glial cells, and also in control BV2 cells overexpressing C/EBPβ. Finally, we observed that histone deacetylase 1 co-immunoprecipitated with C/EBPβ and showed binding to a C/EBPβ consensus sequence of the CD200R1 promoter in LPS-treated glial cells. Moreover, histone deacetylase 1 inhibitors reversed the decrease in CD200R1 expression induced by LPS treatment.

Conclusions

CD200R1 expression decreases in microglial cells in the presence of a pro-inflammatory stimulus, an effect that is regulated, at least in part, by C/EBPβ. Histone deacetylase 1 may mediate C/EBPβ inhibition of CD200R1 expression, through a direct effect on C/EBPβ transcriptional activity and/or on chromatin structure.
Enhancement of Th1-biased protective immunity against avian influenza H9N2 virus via oral co-administration of attenuated Salmonella enterica serovar Typhimurium expressing chicken interferon-α and interleukin-18 along with an inactivated vaccine
Authors: Rahman Md Masudur , Uyangaa Erdenebileg , Han Young Woo , Kim Seong Bum , Kim Jin Hyoung , Choi Jin Young , Eo Seong Kug
Published: July 2012

Background

Control of currently circulating re-assorted low-pathogenicity avian influenza (LPAI) H9N2 is a major concern for both animal and human health. Thus, an improved LPAI H9N2 vaccination strategy is needed to induce complete immunity in chickens against LPAI H9N2 virus strains. Cytokines play a crucial role in mounting both the type and extent of an immune response generated following infection with a pathogen or after vaccination. To improve the efficacy of inactivated LPAI H9N2 vaccine, attenuated Salmonella enterica serovar Typhimurium was used for oral co-administration of chicken interferon-α (chIFN-α) and chicken interleukin-18 (chIL-18) as natural immunomodulators.

Results

Oral co-administration of S. enterica serovar Typhimurium expressing chIFN-α and chIL-18, prior to vaccination with inactivated AI H9N2 vaccine, modulated the immune response of chickens against the vaccine antigen through enhanced humoral and Th1-biased cell-mediated immunity, compared to chickens that received single administration of S. enterica serovar Typhimurium expressing either chIFN-α or chIL-18. To further test the protective efficacy of this improved vaccination regimen, immunized chickens were intra-tracheally challenged with a high dose of LPAI H9N2 virus. Combined administration of S. enterica serovar Typhimurium expressing chIFN-α and chIL-18 showed markedly enhanced protection compared to single administration of the construct, as determined by mortality, clinical severity, and feed and water intake. This enhancement of protective immunity was further confirmed by reduced rectal shedding and replication of AIV H9N2 in different tissues of challenged chickens.

Conclusions

Our results indicate the value of combined administration of chIFN-α and chIL-18 using a Salmonella vaccine strain to generate an effective immunization strategy in chickens against LPAI H9N2.
A genetic bistable switch utilizing nonlinear protein degradation
Authors: Huang Daniel , Holtz William J , Maharbiz Michel M
Published: July 2012

Background

Bistability is a fundamental property in engineered and natural systems, conferring the ability to switch and retain states. Synthetic bistable switches in prokaryotes have mainly utilized transcriptional components in their construction. Using both transcriptional and enzymatic components, creating a hybrid system, allows for wider bistable parameter ranges in a circuit.

Results

In this paper, we demonstrate a tunable family of hybrid bistable switches inE. coliusing both transcriptional components and an enzymatic component. The design contains two linked positive feedback loops. The first loop utilizes the lambda repressor, CI, and the second positive feedback loop incorporates the Lon protease found inMesoplasma florum(mf-Lon). We experimentally tested for bistable behavior in exponential growth phase, and found that our hybrid bistable switch was able to retain its state in the absence of an input signal throughout 40 cycles of cell division. We also tested the transient behavior of our switch and found that switching speeds can be tuned by changing the expression rate ofmf-Lon.

Conclusions

To our knowledge, this work demonstrates the first use of dynamic expression of an orthogonal and heterologous protease to tune a nonlinear protein degradation circuit. The hybrid switch is potentially a more robust and tunable topology for use in prokaryotic systems.
An analysis of Euroqol EQ‐5D and Manchester Oxford Foot Questionnaire scores six months following podiatric surgery
Authors: Maher Anthony J , Kilmartin Timothy E
Published: July 2012

Background

In the United Kingdom patient‐reported outcome measures (PROMS) have been adopted as a key measure of foot surgery outcomes. The intention of this study was to evaluate the responsiveness of a regional outcome measure; the Manchester Oxford Foot Questionnaire (MOXFQ) and a generic measure; the EuroQol EQ‐5D, in the context of day care Podiatric Surgery.

Methods

A prospective audit of 375 consecutive day care surgical admissions was undertaken. All patients attending for surgery, who agreed to participate, were included. Pre operation patients completed the MOXFQ and the EQ‐5D. Both questionnaires were completed again at 6 months post operation. Additional data was collected on patient demographics, surgical procedures and complications.

Results

Few complications were encountered and most patients (84%) returned for a final review 6 months post operation. Mean MOXFQ scores improved for each domain: pain; 51.7 pre‐operation, reduced to 16.5 post‐operation, walking; 50.2 reduced to 14.1 and social interaction; 45.7 reduced to 10.6. The minimal clinically important differences (MCID) estimates for the pain domain were exceeded by 82.6% of patients, while 74.8% exceeded the MCID for walking and 68.5% exceeded the MCID for social interaction. A small number of patients (2.9%) deteriorated across all three MOXFQ domains.

The EQ‐5D Index, summary of health related quality of life, improved from 0.66 pre‐operation to 0.86 post operation. The EQ‐5D index MCID was exceeded by 79.2% of patients. Index scores deteriorated for 1.8% of patients following surgery. Effect sizes measured following surgery were largest for the MOXFQ domains: Walking; 1.39, Pain; 1.52 and Social Interaction: 1.39. The EQ‐5D index effect size was 0.83. The EQ‐5D visual analogue scale (VAS) was not influenced by surgery.

Conclusion

Both the MOXFQ and EQ‐5D index (but not the VAS) appear sensitive to changes in health status at 6 months following elective foot surgery. Both instruments were particularly responsive to changes in pain, mobility and activity or social interaction following treatment. The MOXFQ was developed specifically for foot surgery and as such appears to be the more sensitive instrument. However the generic EQ‐5D may allow comparison of general health states in the wider health community. Both instruments when used together appear well suited to the measurement of change in perceived health status following foot surgery.