bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soluble CCL5 Derived from Bone Marrow-Derived Mesenchymal Stem Cells and Activated by Amyloid β Ameliorates Alzheimer's Disease in Mice by Recruiting Bone Marrow-Induced Microglia Immune Responses
Authors: Lee Jong Kil , Schuchman Edward H. , Jin Hee Kyung , Bae Jae-Sung 
Published: May 2012

Abstract
Microglia have the ability to eliminate amyloid β (Aβ) by a cell-specific phagocytic mechanism, and bone marrow (BM) stem cells have shown a beneficial effect through endogenous microglia activation in the brains of Alzheimer's disease (AD) mice. However, the mechanisms underlying BM-induced activation of microglia have not been resolved. Here we show that BM-derived mesenchymal stem cells (MSCs) induced the migration of microglia when exposed to Aβ in vitro. Cytokine array analysis of the BM-MSC media obtained after stimulation by Aβ further revealed elevated release of the chemoattractive factor, CCL5. We also observed that CCL5 was increased when BM-MSCs were transplanted into the brains of Aβ-deposited AD mice, but not normal mice. Interestingly, alternative activation of microglia in AD mice was associated with elevated CCL5 expression following intracerebral BM-MSC transplantation. Furthermore, by generating an AD-green fluorescent protein chimeric mouse, we ascertained that endogenous BM cells, recruited into the brain by CCL5, induced microglial activation. Additionally, we observed that neprilysin and interleukin-4 derived from the alternative microglia were associated with a reduction in Aβ deposition and memory impairment in AD mice. These results suggest that the beneficial effects observed in AD mice after intracerebral SC transplantation may be explained by alternative microglia activation. The recruitment of the alternative microglia into the brain is driven by CCL5 secretion from the transplanted BM-MSCs, which itself is induced by Aβ deposition in the AD brain.
Synthesis and Characterization of Novel Template Complexes
Authors: A. M. Gad Aleya 
Published: May 2012

AbstractNovel neutral polynuclear NiII chelates of L‐cysteine (L‐cyst) or D‐penicillamine (D‐pen) with dicyandiamide (dcda) were synthesized and characterized using elemental analysis, UV, CD, reflectance, and IR spectroscopy and/or thermogravimetric and X‐ray analysis. The obtained dinuclear compounds add important information about the chemistry of nickel(II) ions, which form types of bonds that cannot be obtained with other metal ions such as CoII. These dinuclear nickel compounds contain four‐membered rings with two sulfur and two nickel atoms. Electronic transitions were elucidated from reflectance, CD and absorbance spectroscopy and confirm a distorted square planar arrangement of the nickel ions. Because the same structure with CoII ions could not be obtained directly, dimethylglyoxime was added to a suspension of the template complex with D‐pen in water to separate the nickel ions. The separation of the ligand was confirmed by elemental analysis, IR, and 1H NMR spectroscopy. It reacted with CoII to give a different mononuclear crystalline complex that was studied by X‐ray single crystal diffraction. The crystals are orthorhombically with space group C2221, a = 0.11769(4) pm, b = 0.13632(4) pm, c = 0.25239(8) pm, V = 0.0040490(2) pm3, and Z = 8.
The False‐Negative Rate of Sentinel Node Biopsy in Patients with Breast Cancer: A Meta‐Analysis
Authors: Pesek Sarah , Ashikaga Taka , Krag Lars Erik , Krag David 
Published: May 2012

AbstractBackgroundIn sentinel node surgery for breast cancer, procedural accuracy is assessed by calculating the false‐negative rate. It is important to measure this since there are potential adverse outcomes from missing node metastases. We performed a meta‐analysis of published data to assess which method has achieved the lowest false‐negative rate.MethodsWe found 3,588 articles concerning sentinel nodes and breast cancer published from 1993 through mid‐2011; 183 articles met our inclusion criteria. The studies described in these 183 articles included a total of 9,306 patients. We grouped the studies by injection material and injection location. The false‐negative rates were analyzed according to these groupings and also by the year in which the articles were published.ResultsThere was significant variation related to injection material. The use of blue dye alone was associated with the highest false‐negative rate. Inclusion of a radioactive tracer along with blue dye resulted in a significantly lower false‐negative rate. Although there were variations in the false‐negative rate according to injection location, none were significant.ConclusionsThe use of blue dye should be accompanied by a radioactive tracer to achieve a significantly lower false‐negative rate. Location of injection did not have a significant impact on the false‐negative rate. Given the limitations of acquiring appropriate data, the false‐negative rate should not be used as a metric for training or quality control.
Antibiotics as First‐line Therapy for Acute Appendicitis: Evidence for a Change in Clinical Practice
Authors: Hansson Jeanette , Körner Ulla , Ludwigs Karin , Johnsson Erik , Jönsson Claes , Lundholm Kent 
Published: May 2012

AbstractBackgroundRandomized studies have indicated that acute appendicitis may be treated by antibiotics without the need of surgery. However, concerns have been raised about selection bias of patients in such studies. Therefore, the present study was aimed to validate previous findings in randomized studies by a full‐scale population‐based application.MethodsAll patients with acute appendicitis at Sahlgrenska University Hospital (May 2009 and February 2010) were offered intravenous piperacillin plus tazobactam according to our previous experience, followed by 9 days out‐hospital oral ciprofloxacin plus metronidazole. Endpoints were treatment efficacy and complications. Efficient antibiotic treatment was defined as recovery without the need of surgery beyond 1 year of follow‐up.ResultsA total of 558 consecutive patients were hospitalized and treated due to acute appendicitis. Seventy‐nine percent (n = 442) received antibiotics as first‐line therapy and 20 % (n = 111) had primary surgery as the second‐line therapy. Seventy‐seven percent of patients on primary antibiotics recovered while 23 % (n = 100) had subsequent appendectomy due to failed initial treatment on antibiotics. Thirty‐eight patients (11 %) of the 342 had experienced recurrent appendicitis at 1‐year follow‐up. Primary antibiotic treatment had fewer complications compared to primary surgery.ConclusionsThis population‐based study confirms previous results of randomized studies. Antibiotic treatment can be offered as the first‐line therapy to a majority of unselected patients with acute appendicitis without medical drawbacks other than the unknown risk for long‐term relapse, which must be weighed against the unpredicted but well‐known risk for serious major complications following surgical intervention.
Variability and change in the Canadian cryosphere
Authors: Derksen C. , Smith S. L. , Sharp M. , Brown L. , Howell S. , Copland L. , Mueller D. R. , Gauthier Y. , Fletcher C. G. , Tivy A. , Bernier M. , Bourgeois J. , Brown R. , Burn C. R. , Duguay C. , Kushner P. , Langlois A. , Lewkowicz A. G. , Royer A. , Walker A. 
Published: May 2012

Abstract
During the International Polar Year (IPY), comprehensive observational research programs were undertaken to increase our understanding of the Canadian polar cryosphere response to a changing climate. Cryospheric components considered were snow, permafrost, sea ice, freshwater ice, glaciers and ice shelves. Enhancement of conventional observing systems and retrieval algorithms for satellite measurements facilitated development of a snapshot of current cryospheric conditions, providing a baseline against which future change can be assessed. Key findings include: 1. surface air temperatures across the Canadian Arctic exhibit a warming trend in all seasons over the past 40 years. A consistent pan-cryospheric response to these warming temperatures is evident through the analysis of multi-decadal datasets; 2. in recent years (including the IPY period) a higher rate of change was observed compared to previous decades including warming permafrost, reduction in snow cover extent and duration, reduction in summer sea ice extent, increased mass loss from glaciers, and thinning and break-up of the remaining Canadian ice shelves. These changes illustrate both a reduction in the spatial extent and mass of the cryosphere and an increase in the temporal persistence of melt related parameters. The observed changes in the cryosphere have important implications for human activity including the close ties of northerners to the land, access to northern regions for natural resource development, and the integrity of northern infrastructure.
The Evolution and Treatment of Korsakoff's Syndrome
Authors: Thomson A. D. , Guerrini Irene , Marshall E. Jane 
Published: May 2012

AbstractWernicke’s Encephalopathy is an acute neuro-psychiatric condition caused by an insufficient supply of thiamine (Vitamin B1) to the brain. If undiagnosed or inadequately treated, it is likely to proceed to Korsakoff’s Syndrome. Wernicke’s Encephalopathy can result from dietary deficiency alone and this form is usually successfully treated, with little chance of Korsakoff’s Syndrome supervening. On the other hand, thiamine deficiency associated with alcohol misuse/dependence may require up to 1 gram of thiamine IV in the first 24 hours to be treated successfully. The reasons for this difference in treatment will be discussed. Thiamine diphosphate acts as a co-factor for a number of thiamine-dependent enzymes. Thiamine deficiency leads to a reduction in the activity of these enzymes, and this leads to alterations in mitochondrial activity, impairment of oxidative metabolism, decreased energy status and eventually selective neuronal death. The damage caused by the combination of thiamine deficiency and alcohol metabolism probably interferes with adequate thiamine transport at a number of sites in the body, including the blood–brain barrier, as well as causing damage to the apoenzymes which then require higher concentrations of thiamine to work normally. The accumulated damage is likely to render the use of oral thiamine therapeutically inadequate since the body is unable to produce high enough concentrations of thiamine in the blood to traverse the blood–brain barrier. Some individuals are probably genetically predisposed to develop Wernicke’s. Long before individuals with alcohol misuse or dependence develop Wernicke’s Encephalopathy the neurons and other cells of the body are functioning sub-optimally because of the inadequate supply of thiamine and the neurotoxic effect of alcohol. This relative deficiency initiates a series of pathological changes which accumulate and further interfere with the supply of thiamine and its utilisation at a time when the requirements are increased. The best treatment for Korsakoff’s Syndrome is timely recognition of Wernicke’s Encephalopathy and appropriate intervention and prevention.
Severe oligozoospermia in a patient with myxedema coma
Authors: Komiya Akira , Watanabe Akihiko , Kawauchi Yoko , Takano Atsuko , Fuse Hideki 
Published: May 2012

AbstractA case of severe oligozoospermia with myxedema coma is herein presented. The patient was referred to a male infertility clinic with a 5‐year history of primary infertility. Decreased serum testosterone and elevated serum prolactin without abnormal MRI findings in the hypothalamus, and decreased semen volume and sperm motility were noted. A GnRH test revealed a decreased luteinizing hormone response, whereas the HCG test showed a normal testosterone increase. Because a urinalysis after ejaculation indicated retrograde ejaculation, imipramine administration was started. However, the semen quality deteriorated, so the patient was referred to an ART clinic. Twenty‐one months from the initial visit, the patient developed a loss of consciousness and edema due to myxedema coma, a life‐threatening state of hypothyroidism. The patient recovered after 1 month of thyroid hormone replacement therapy (HRT) with corticosteroids. Three months after the myxedema coma, a semen analysis showed a decreased semen volume (0.2 mL) and severe oligozoospermia (two spermatozoa/ejaculate). Elevated prolactin and decreased testosterone levels were still present. These parameters gradually improved after restoration of euthyroidism by HRT. In conclusion, physicians should confirm the thyroid function in the management of male infertility, especially in patients with elevated prolactin levels.
PLGA nanoparticles loaded with etoposide and quercetin dihydrate individually: in vitro cell line study to ensure advantage of combination therapy
Authors: Pimple Smita , Manjappa Arehalli S. , Ukawala Mukesh , Murthy R. S. R. 
Published: May 2012

Abstract
PLGA nanoparticles, separately loaded with etoposide (ETN) and quercetin dihydrate (QDN), were prepared by adapting the solvent diffusion (nanoprecipitation) technique. The effect of formulation variables such as amount of polymer, theoretical drug loading, surfactant concentration, and aqueous and organic phase volumes on particle size and entrapment efficiency, were systematically studied. The optimal formulations obtained were of submicron size (153.4 ± 4.2 nm for ETN and 148.6 ± 1.6 nm for QDN) and with low polydispersity indices (0.058 ± 0.02 for ETN and 0.088 ± 0.03 for QDN). The entrapment efficiencies were found as 63.88 ± 1.5 % and 41.36 ± 3.4 % for ETN and QDN, respectively. The characterization of ETN and QDN was done by measuring the zeta potential, TEM, and DSC analysis. The comparison was made in respect of in vitro cytotoxicity assay using cancer cell line A549 (human lung adenocarcinoma epithelial cell line). The results revealed significant increase in cytotoxicity in nanoparticle formulations than their respective free drug. The comparison was also made with respect to cytotoxic activity of individual drug and combination of drugs in the form of free drugs as well as nanoparticles. The combination treatment in the form of nanoparticles is found to produce best results among the treatments used in cytotoxicity studies.
Ecology and evolution of pine life histories
Authors: Keeley Jon E. 
Published: May 2012

Abstract

Introduction

Pinus is a diverse genus of trees widely distributed throughout the Northern Hemisphere. Understanding pine life history is critical to both conservation and fire management.

Objectives

Here I lay out the different pathways of pine life history adaptation and a brief overview of pine evolution and the very significant role that fire has played.

Results

Pinus originated ~150 Ma in the mid-Mesozoic Era and radiated across the northern continent of Laurasia during the Cretaceous Period. Pines have followed two evolutionary strategies interpreted as responses to competition by the newly emerging angiosperms. The Strobus lineage mostly has radiated into stressful sites of low nutrient soils and extremes in cold or heat. The Pinus (subgenus) lineage has radiated into fire-prone landscapes with diverse fire regimes. Examination of life history traits illustrates syndromes associated with fire-avoider, fire-tolerater, fire-embracer, and fire-refuge strategies.

Conclusion

Understanding the current pattern of pine distribution requires interpreting their evolution in terms of climate, geology, and fire. All three of these factors have played a role since the Mesozoic origin of the genus. All are important to the appropriate management of these resources.
Factors Impacting on Performance of Lobe Pumps: A Numerical Evaluation
Authors: Kang Y.-H. , Vu H.-H. , Hsu C.-H. 
Published: May 2012

AbstractThe aim of current research is to investigate numerically the fluid dynamics of lobe pumps and typical factors which could impact on performance of the pump including profile of rotor surface, number of lobes, gap size between rotor and casing, and clearance between two rotors,etc. The circular and epicycloidal curves are used to generate profiles for rotor surface, while the complex flow phenomena inside the pump are simulated by dynamic mesh technique. With wide range of investigated speed from 1000 to 5000rpm, the study produces significant information on flow pattern, velocity and pressure fields. The advantage of epicycloidal pumps over circular ones has been demonstrated via characteristic curve which performs pressure head versus rotational speed. Meanwhile the analysis has proved that multilobes, three and four lobes, do not increase performance of the pump but provide more stable output and higher capacity compared with two-lobe pumps. The results confirm great impact of gap size between rotor and casing wall on the pump efficiency. Decrease of the gap from 1.25mm down to 0.5mm produces about 425% increasing of pressure head. In addition, it has been also proved that the clearance between two rotors could be varied from 0.12mm to 0.15mm without much effect on performance of the pump.
The Investigation of Effective Material Concept for the Transient Wave Propagation in Multilayered Media
Authors: Lin Y.-H. , Ma C.-C. 
Published: May 2012

AbstractIn this article, the dynamic response in a multilayered medium is analyzed by Laplace transform technique. The thickness and material constant in each layer are different. The medium is subjected an uniformly distributed loading at the upper surface, and the bottom surface is assumed to be traction-free. The analytical solutions are presented in the transform domain and the numerical Laplace inversion (Durbin's formula) is performed to obtain the transient response in time domain. The effective material concept is usually used to simplify multilayered media in static analysis. The numerical calculations of the transient responses for randomly distributed, periodically distributed, and continuously distributed multilayered media are performed to investigate if the effective material concept is suitable for dynamic analysis.
Attitude-Adjustment-Induced Sloshing Characteristics in a Satellite Propellant Tank
Authors: Yang A.-S. 
Published: May 2012

AbstractThe fluid sloshing behavior in a propellant tank is a major concern for the control and stabilization of a spacecraft. This research aims to investigate the attitude-adjustment-induced sloshing phenomenon in a satellite propellant tank under microgravities. In the analysis, the complicated interfacial flow was simulated using the transient three-dimensional conservation equations of mass and momentum with treatment of the surface tension effect at the interface boundary by the continuum surface force (CSF) model. The volume-of-fluid (VOF) method in conjunction with the piecewise linear interface construction (PLIC) technique was also utilized to describe the fluid interface motions. Computations were performed to simulate the sloshing process in the FORMOSAT-2 propellant tank for determining the impact disturbance properties generated during the pitch maneuver. Because the predicted disturbance moments were well below the design control moments, the attitude-adjustment-induced sloshing effect would not cause any performance deterioration for satisfactory attitude modification of the satellite.
Square-Cylinder Flow Characteristics Modulated Using Upstream Control Rod
Authors: Yen S. C. , Wu S. F. 
Published: May 2012

AbstractThe flow patterns, vortex-shedding frequency and aerodynamic performance of the square-cylinder flow were modulated using an upstream control rod. Additionally, the flow behaviors were examined using various Reynolds numbers, rotation angles, and spacing ratios. The flow patterns were visualized using the smoke-wire scheme. The global velocity fields and streamline patterns were analyzed using the particle image velocimetry (PIV). Additionally, the flow modes were characterized based on the kinematics theory. Moreover, the vortex-shedding frequencies behind upstream control rod and the square cylinder were detected using two hot-wire anemometers. The surface pressure on square cylinder was determined using a linear pressure scanner. Then, the aerodynamic parameters were calculated using the surface-pressure profiles. Three characteristic flow modes — single, attached, and bi-vortex-street — were categorized by varying the Reynolds number and spacing ratio. In the attached mode, the position of upstream control rod determined the flow characteristics. Furthermore, in the attached mode, the mean drag force of the square cylinder is about 57% lower than of single-square cylinder.
Advancing Diffusion Model for Diffusion in a Cube of Medium
Authors: Lin C.-C. , Tsai C.-L. , Wu P.-K. , Lee H.-J. 
Published: May 2012

AbstractA solution based on an advancing model for the content of diffusion material in a cube of medium is derived. The cube is assumed to be surrounded by diffusion material, and the diffusion material penetrates through all six surfaces and diffuses toward the center of the cube. The model accounts for the interaction between the diffusions in the three principle coordinates of the Cartesian coordinate system. For the first time, an exact solution of the content of the diffusion material based on the advancing model is derived in a clean form for a three-dimensional case.
Rotating Moderately Thick Annular Disks via an Extension to Classical Theory
Authors: Zenkour A. M. 
Published: May 2012

AbstractThe problem of rotating annular disk subjected to a uniformly distributed load is treated in two ways. Stress is divided into a rotating part because of the angular velocity and a bending part due to force loading. New set of equilibrium equations with small deflections is developed. Solutions for radial displacement, deflection, forces and moment resultants, and the rotating and bending stresses of the first-order theory are presented in terms of corresponding quantities of annular disks based on the classical theory. The boundary conditions at the edges of the annular disk are roller supported, clamped or free. Several examples are presented to illustrate the use and accuracy of these relationships. The effects of several parameters on the radial and vertical displacements and rotating and bending stresses are studied. It is observed that the classical theory is sufficient to study the problem of rotating annular disks. However, the inclusion of the effect of shear deformation is necessary to study precisely the curvature of moderately thick annular disks.
Stochastic Dynamic Response of a Simplified Nonlinear Fluid Model for Viscoelastic Materials
Authors: Chang T.-P. 
Published: May 2012

AbstractIn the present study, we propose a simplified nonlinear fluid model to characterize the complex nonlinear response of some viscoelastic materials. Recently, the viscoelastic modeling has been utilized by many researchers to simulate some parts of human body in bioengineering and to represent many material properties in mechanical engineering, electronic engineering and construction engineering. Occasionally it is almost impossible to evaluate the constant parameters in the model in the deterministic sense, therefore, the damping coefficient of the dashpot and the spring constants of the linear and nonlinear springs are considered as stochastic to model the stochastic properties of the viscoelastic materials. After some transformations, the closed-form solution can be obtained for the mean value of the displacement of the simplified nonlinear fluid model, subjected to constant rate of displacement. Based on the closed-form solution, the proposed method generates the stochastic dynamic response of the simplified nonlinear model, which plays an important role in performing the reliability analysis of the nonlinear system.