julilili42/papers huggingface dataset:
Clinical PET/MRI-System and Its Applications with MRI Based Attenuation Correction
2009-10-01

Clinical PET/MRI is an emerging new hybrid imaging modality. In addition to provide an unique possibility for multifunctional imaging with temporally and spatially matched data, it also provides anatomical information that can also be used for attenuation correction with no radiation exposure to the subjects. A plus of combined compared to sequential PET and MR imaging is the reduction of total scan time. Here we present our initial experience with a hybrid brain PET/MRI system. Due to the ethical approval patient scans could only be performed after a diagnostic PET/CT. We estimate that in approximately 50 of the cases PET/MRI was of superior diagnostic value compared to PET/CT and was able to provide additional information, such as DTI, spectroscopy and Time Of Flight (TOF) angiography. Here we present 3 patient cases in oncology, a retropharyngeal carcinoma in neurooncology, a relapsing meningioma and in neurology a pharyngeal carcinoma in addition to an infraction of the right hemisphere. For quantitative PET imaging attenuation correction is obligatory. In current PET/MRI setup we used our MRI based atlas method for calculating the mu-map for attenuation correction. MR-based attenuation correction accuracy was quantitatively compared to CT-based PET attenuation correction. Extensive studies to assess potential mutual interferences between PET and MR imaging modalities as well as NEMA measurements have been performed. The first patient studies as well as the phantom tests clearly demonstrated the overall good imaging performance of this first human PET/MRI system. Ongoing work concentrates on advanced normalization and reconstruction methods incorporating count-rate based algorithms.
Vasoregression Linked to Neuronal Damage in the Rat with Defect of Polycystin-2
2009-10-05

Our data suggest that TGR is an appropriate animal model for vasoregression related to neuronal damage. Similarities to experimental diabetic retinopathy render this model suitable to understand general mechanisms of maturity-onset vasoregression.
Early but not late stent thrombosis is influenced by residual platelet aggregation in patients undergoing coronary interventions
2009-10-06

Post-interventional RPA is associated with the occurrence of early ST in patients treated with either BMS or DES; however, there is no predictive value of RPA for the incidence of 3-month LAT, suggesting the involvement of other possible mechanisms like discontinuation of antiplatelet therapy.
Combined Risk Allele Score of Eight Type 2 Diabetes Genes Is Associated With Reduced First-Phase Glucose-Stimulated Insulin Secretion During Hyperglycemic Clamps
2009-10-06

OBJECTIVE At least 20 type 2 diabetes loci have now been identified, and several of these are associated with altered β-cell function. In this study, we have investigated the combined effects of eight known β-cell loci on insulin secretion stimulated by three different secretagogues during hyperglycemic clamps. RESEARCH DESIGN AND METHODS A total of 447 subjects originating from four independent studies in the Netherlands and Germany (256 with normal glucose tolerance [NGT]/191 with impaired glucose tolerance [IGT]) underwent a hyperglycemic clamp. A subset had an extended clamp with additional glucagon-like peptide (GLP)-1 and arginine (n = 224). We next genotyped single nucleotide polymorphisms in TCF7L2, KCNJ11, CDKAL1, IGF2BP2, HHEX/IDE, CDKN2A/B, SLC30A8, and MTNR1B and calculated a risk allele score by risk allele counting. RESULTS The risk allele score was associated with lower first-phase glucose-stimulated insulin secretion (GSIS) (P = 7.1 × 10−6). The effect size was equal in subjects with NGT and IGT. We also noted an inverse correlation with the disposition index (P = 1.6 × 10−3). When we stratified the study population according to the number of risk alleles into three groups, those with a medium- or high-risk allele score had 9 and 23% lower first-phase GSIS. Second-phase GSIS, insulin sensitivity index and GLP-1, or arginine-stimulated insulin release were not significantly different. CONCLUSIONS A combined risk allele score for eight known β-cell genes is associated with the rapid first-phase GSIS and the disposition index. The slower second-phase GSIS, GLP-1, and arginine-stimulated insulin secretion are not associated, suggesting that especially processes involved in rapid granule recruitment and exocytosis are affected in the majority of risk loci.
Possible freshwater resource consumption by the earliest directly dated European modern humans: Implications for direct radiometric dating
2009-10-06

Possible freshwater resource consumption by the earliest directly dated European modern humans: Implications for direct radiometric dating Richards and Trinkaus (1) infer from bone collagen carbon and nitrogen stable isotopic composition a significant contribution of freshwater resources in the diet of early European modern humans, especially for the oldest directly dated specimen from Pes ̧tera cu Oase, Romania.Although the confirmation of such diet still requires direct comparison of contemporaneous fauna from the same region (2), such a claim raises the question of a possible increase of radiocarbon ages due to freshwater reservoir effect.It has been documented that freshwater resources and their consumers exhibit lower 14 C amounts in their organic matter than terrestrial resources at a given time, which makes them look significantly older, up to 1,200 years (e.g., ref. 3).Such an increase of apparent age has also been documented in some archaeological sites, such as the Iron Gates Gorge along the Danube River at the Serbian-Romanian border (3, 4).Therefore, a precise
Aesthetic Appraisal of Art - from Eye Movements to Computers
2009-10-06

By looking at a work of art, an observer enters into a dialogue. In this work, we attempt to analyze this dialogue with both behavioral and computational tools. In two experiments, observers were asked to look at a large number of paintings from different art periods and to rate their visual complexity, or their aesthetic appeal. During these two tasks, their eye movements were recorded. The complexity and aesthetic ratings show clear preferences for certain artistic styles and were based on both low-level and high-level criteria. Eye movements reveal the time course of the aesthetic dialogue as observers try to interpret and understand the painting. Computational analyses of both the ratings (using measures derived from information theory) and the eye tracking data (using two models of saliency) showed that our computational tools are already able to explain some properties of this dialogue.
Dynamic Grid Refinement for Fluid Simulations on Parallel Graphics Architectures
2009-10-06

We present a physically-based fluid simulation with dynamic grid refinement on parallel SIMD graphics hardware. The irregular and dynamic structure of an adaptive grid requires sophisticated memory access patterns as well as a decomposition of the problem for parallel processing and the distribution of tasks to multiple threads. In this paper, we focus on the representation and management of the dynamic grid on the graphics device for an efficient parallelization of the advection step and the iterative solving of the Poisson equation. In order to achieve high performance, we utilize the hardware's capabilities like fast cache access and trilinear filtering. Furthermore, expensive data transfer between host and device is minimized to avoid a major bottleneck. We report results on the inherent overhead of the dynamic grid compared to an equivalent Cartesian grid. In addition, a visual simulation of smoke is presented with radiosity-based illumination and volume ray casting at interactive frame rates.
Molecular and Genetic Dissection of Cereal Root System Development
2009-10-07

This chapter contains sections titled: Introduction Morphology of cereal root systems Morphological and anatomical comparison of Arabidopsis and cereal root systems Molecular and genetic analysis of cereal root formation Prospects
Persistent Troponin Elevation in a Patient with Cardiac Amyloidosis
2009-10-08

Abstract A 79‐year‐old patient repeatedly presented with chest discomfort and dyspnea on exertion. With echocardiography a prominent left ventricular and septal hypertrophy was detected with reduced left ventricular function. Despite successful revascularization and excellent results after stenting, the patient showed persistently elevated troponin levels. To investigate the abnormal findings of persistent troponin elevation, septal hypertrophy, and heart failure we performed endomyocardial biopsies which showed widespread myocardial amyloidosis. Amyloid subtyping revealed transthyretin amyloidosis. This is the first case showing persistent troponin elevation in a patient with tranthyretin amyloidosis. Very few other cases have been published on the topic of cardiac amyloidosis and troponin elevation so far. Our case serves as an illustrating example in the differential diagnosis of nonischemic causes of persistent troponin elevation. It is important to consider cardiac amyloidosis in patients with troponin elevation and heart failure since the clinical management differs significantly from other causes of heart failure. Copyright © 2009 Wiley Periodicals, Inc.
Site-Specific Charge-Transfer Screening at Organic/Metal Interfaces
2009-10-09

Site-specific core hole screening effects at organic/metal interfaces were studied using core-level X-ray photoemission spectroscopy (XPS), X-ray excited Auger electron spectroscopy (XAES), and valence band ultraviolet photoemission spectroscopy (UPS). As model molecules, we chose zinc phthalocyanine (ZnPc) and its perfluorinated derivative ZnPcF16 evaporated on Au(100). For the first molecular layer on the metal surface, we observe for both molecules a clear splitting of the Zn L3M4,5M4,5 signal clue to strongly increased screening in the double-hole final states In contrast, F KL2,3L2,3. Auger spectra do not show additional features at any stage of deposition. Site-dependent screening effects are discussed in terms of polarization and charge-transfer screening.
Inhibitors of the Microsomal Prostaglandin E2 Synthase-1 as Alternative to Non Steroidal Anti-Inflammatory Drugs (NSAIDs) – A Critical Review
2009-10-10

Pharmacological suppression of cyclooxygenase (COX)-1 and -2-mediated prostanoid biosynthesis by non steroidal anti-inflammatory drugs (NSAIDs) is used in the therapy of inflammation, fever, and pain. However, long-term application of these drugs is associated with severe side effects, mainly gastrointestinal injury and renal irritations, apparently due to impaired biosynthesis of physiologically relevant prostanoids. Although COX-2 selective drugs (coxibs) show reduced gastrointestinal complications, recent clinical trials indicated a significantly increased cardiovascular risk. In order to minimize these side-effects, selective suppression of microsomal prostaglandin E2 synthase (mPGES)-1 derived prostaglandin (PG)E2 formation has been considered as alternative to general inhibition of prostanoid biosynthesis. mPGES-1 is functionally coupled to COX-2 being responsible for excessive PGE2 generation connected to pathologies and current knowledge suggests key roles of mPGES-1 in inflammation, pain, fever, atherosclerosis, and tumorigenesis. However, mPGES-1 as promising therapeutic target was questioned because blockade of mPGES-1 allows redirection of the substrate PGH2 to other PG synthases, and the consequences are still elusive. This review summarizes current knowledge about synthetic and natural mPGES-1 inhibitors focusing on structural and mechanistic investigations. Further, the therapeutic efficiency and safety is critically discussed on the basis of cellular and animal studies in which mPGES-1 activity was pharmacologically or genetically (knockout, knockdown) modulated.
The Insulin Effect on Cerebrocortical Theta Activity Is Associated with Serum Concentrations of Saturated Nonesterified Fatty Acids
2009-10-10

Context: Insulin action in the brain contributes to adequate regulation of body weight, neuronal survival, and suppression of endogenous glucose production. We previously demonstrated by magnetoencephalography in lean humans that insulin stimulates activity in beta and theta frequency bands, whereas this effect was abolished in obese individuals. Objective: The present study aims to define metabolic signals associated with the suppression of the cerebrocortical response in obese humans. Design and Setting: We determined insulin-mediated modulation of spontaneous cerebrocortical activity by magnetoencephalography during a hyperinsulinemic euglycemic clamp and related it to measures of ectopic fat deposition and mediators of peripheral insulin resistance. Visceral fat mass and intrahepatic lipid content were quantified by magnetic resonance imaging and spectroscopy. Multiple regression analysis was used to analyze associations of cerebrocortical insulin sensitivity and metabolic markers related to obesity. Participants: Forty-nine healthy, nondiabetic humans participated in the study. Results: In a multiple regression, insulin-mediated stimulation of theta activity was negatively correlated to body mass index, visceral fat mass, and intrahepatic lipid content. Although fasting saturated nonesterified fatty acids mediated the correlations of theta activity with abdominal and intrahepatic lipid stores, adipocytokines displayed no independent correlation with insulin-mediated cortical activity in the theta frequency band. Conclusions: Thus, insulin action at the level of cerebrocortical activity in the brain is diminished in the presence of elevated levels of saturated nonesterified fatty acids. High serum concentrations of saturated nonesterified fatty acids are associated with a decreased insulin effect on cortical activity in the human brain.
A meningioma of the scalp that might have developed from a rudimentary meningocele
2009-10-10

Meningiomas of the skin are extremely rare. In this case of a congenital meningioma of the scalp, magnetic resonance imaging showed no communication to the meninges. The histological examination discovered a small group of meningioma cells in the periosteum, supporting the assumption that primary cutaneous meningiomas may develop from rudimentary meningoceles.
Susceptibility testing of amorolfine, bifonazole and ciclopiroxolamine againstTrichophyton rubrumin anin vitromodel of dermatophyte nail infection
2009-10-11

Antimycotic nail lacquers are effective and safe for the treatment of onychomycosis. To assess the efficacy of three topical agents we studied the minimum inhibitory and fungicidal concentration of amorolfine, bifonazole and ciclopiroxolamine. Amorolfine showed the most effective fungistatic and fungicidal activity in vitro against seven clinical Trichophyton rubrum nail isolates, followed in descending order by ciclopiroxolamine and bifonazole. To mimic a nail infection more appropriately, the nail minimum fungicidal concentration (Nail-MFC) was determined in an onychomycosis model. Amorolfine and ciclopiroxolamine had Nail-MFCs ranging from 2-32 microg/ml and 16-32 microg/ml, respectively. In contrast, bifonazole was unable to kill T. rubrum in this model. Statistical analyses of the results show a significant difference between the two treatments with amorolfine and ciclopiroxolamine (P<0.001). For amorolfine a mean concentration of 12.28 microg/ml (95%-CI=[8.66, 17.41]) was sufficient to kill all strains, while for ciclopiroxolamine about twice that concentration was needed, i.e., 24.13 microg/ml (95%-CI=[17.06, 34.13]). The individual sensitivity of six of the seven T. rubrum strains was higher for amorolfine. These data demonstrate that both amorolfine and ciclopiroxolamine effectively kill T. rubrum growing on nail powder and suggest a better cidal action for amorolfine. Further investigation would be required to determine if these in vitro data can partially explain the clinical observation of significantly higher cure rates in onychomycosis following a therapy with an amorolfine-containing nail lacquer formulation.
A Variant of the SLC10A2 Gene Encoding the Apical Sodium-Dependent Bile Acid Transporter Is a Risk Factor for Gallstone Disease
2009-10-12

We have identified SLC10A2 as a novel susceptibility gene for cholelithiasis in humans. Comprehensive statistical analysis provides strong evidence that rs9514089 is a genetic determinant especially in male non-obese gallstone carriers. The minor allele of rs9514089 is related to differences in plasma cholesterol levels among the subjects.
No effect of mate novelty on sexual motivation in the freshwater snail Biomphalaria glabrata
2009-10-12

Abstract Background When mating effort (e.g. via ejaculates) is high, males are expected to strategically allocate their resources depending on the expected fitness gains from a given mating opportunity. One mechanism to achieve strategic mating is the Coolidge effect, where male sexual motivation declines across repeated encounters with a familiar partner, but resuscitates when encountering a novel female. Experimental tests of male mate choice via mechanisms such as the Coolidge effect, however, remain scarce. Moreover, it is untested to date whether the Coolidge effect occurs in a sex-specific manner in simultaneous hermaphrodites, where the motivation to mate with a familiar partner may vary with previous mating activity in the male or female role. Results We exposed focal hermaphroditic freshwater snails, Biomphalaria glabrata , repeatedly to either a familiar or a novel partner. None of our proxies of sexual motivation (remating likelihood, mating delay, copulation duration) varied between the novel and familiar partner treatments. Moreover, the mating role taken during the first copulation did not affect the subsequent choice of mating roles in the familiar partner treatment as would be expected if focals preferred to avoid mating twice in the same role with a familiar partner. This indicates the absence of sex-specific effects of partner novelty. Conclusion Our data indicate that mate novelty does affect neither overall sexual motivation nor the choice of mating roles in B. glabrata . Hence, male mate choice via a Coolidge effect appears inexistent in this invertebrate hermaphrodite. We discuss the possible roles of insufficient fitness gains for discriminatory behaviour in populations with frequent mate encounters as well as poor mate discrimination capacities. Our findings lend also no support to the novel prediction that sexual motivation in simultaneous hermaphrodites varies with the mating roles taken during previous copulations, calling for empirical investigation in further hermaphrodite systems.
Black holes and neutron stars in the generalized tensor-vector-scalar theory
2009-10-13

Bekenstein's Tensor-Vector-Scalar (TeVeS) theory has had considerable success as a relativistic theory of Modified Newtonian Dynamics (MoND). However, recent work suggests that the dynamics of the theory are fundamentally flawed and numerous authors have subsequently begun to consider a generalization of TeVeS where the vector field is given by an Einstein-Aether action. Herein, I develop strong-field solutions of the generalized TeVeS theory, in particular exploring neutron stars as well as neutral and charged black holes. I find that the solutions are identical to the neutron star and black hole solutions of the original TeVeS theory, given a mapping between the parameters of the two theories, and hence provide constraints on these values of the coupling constants. I discuss the consequences of these results in detail including the stability of such spacetimes as well as generalizations to more complicated geometries.
Overexpression of Kinase-Negative Protein Kinase Cδ in Pancreatic β-Cells Protects Mice From Diet-Induced Glucose Intolerance and β-Cell Dysfunction
2009-10-13

OBJECTIVE In vitro models suggest that free fatty acid–induced apoptotic β-cell death is mediated through protein kinase C (PKC)δ. To examine the role of PKCδ signaling in vivo, transgenic mice overexpressing a kinase-negative PKCδ (PKCδKN) selectively in β-cells were generated and analyzed for glucose homeostasis and β-cell survival. RESEARCH DESIGN AND METHODS Mice were fed a standard or high-fat diet (HFD). Blood glucose and insulin levels were determined after glucose loads. Islet size, cleaved caspase-3, and PKCδ expression were estimated by immunohistochemistry. In isolated islet cells apoptosis was assessed with TUNEL/TO-PRO3 DNA staining and the mitochondrial potential by rhodamine-123 staining. Changes in phosphorylation and subcellular distribution of forkhead box class O1 (FOXO1) were analyzed by Western blotting and immunohistochemistry. RESULTS PKCδKN mice were protected from HFD-induced glucose intolerance. This was accompanied by increased insulin levels in vivo, by an increased islet size, and by a reduced staining of β-cells for cleaved caspase-3 compared with wild-type littermates. In accordance, long-term treatment with palmitate increased apoptotic cell death of isolated islet cells from wild-type but not from PKCδKN mice. PKCδKN overexpression protected islet cells from palmitate-induced mitochondrial dysfunction and inhibited nuclear accumulation of FOXO1 in mouse islet and INS-1E cells. The inhibition of nuclear accumulation of FOXO1 by PKCδKN was accompanied by an increased phosphorylation of FOXO1 at Ser256 and a significant reduction of FOXO1 protein. CONCLUSIONS Overexpression of PKCδKN in β-cells protects from HFD-induced β-cell failure in vivo by a mechanism that involves inhibition of fatty acid–mediated apoptosis, inhibition of mitochondrial dysfunction, and inhibition of FOXO1 activation.
Tuber‐specific cphA expression to enhance cyanophycin production in potatoes
2009-10-13

Summary The production of biodegradable polymers that can be used to substitute petrochemical compounds in commercial products in transgenic plants is an important challenge for plant biotechnology. Nevertheless, it is often accompanied by reduced plant fitness. To decrease the phenotypic abnormalities of the sprout and to increase polymer production, we restricted cyanophycin accumulation to the potato tubers by using the cyanophycin synthetase gene ( cph A Te ) from Thermosynechococcus elongatus BP‐1, which is under the control of the tuber‐specific class 1 promoter (B33). Tuber‐specific cytosolic (pB33‐ cph A Te ) as well as tuber‐specific plastidic (pB33‐PsbY‐ cph A Te ) expression resulted in significant polymer accumulation solely in the tubers. In plants transformed with pB33‐ cph A Te , both cyanophycin synthetase and cyanophycin were detected in the cytoplasm leading to an increase up to 2.3% cyanophycin of dry weight and resulting in small and deformed tubers. In B33‐PsbY‐ cph A Te tubers, cyanophycin synthetase and cyanophycin were exclusively found in amyloplasts leading to a cyanophycin accumulation up to 7.5% of dry weight. These tubers were normal in size, some clones showed reduced tuber yield and sometimes exhibited brown sunken staining starting at tubers navel. During a storage period over of 32 weeks of one selected clone, the cyanophycin content was stable in B33‐PsbY‐ cph A Te tubers but the stress symptoms increased. However, all tubers were able to germinate. Nitrogen fertilization in the greenhouse led not to an increased cyanophycin yield, slightly reduced protein content, decreased starch content, and changes in the amounts of bound and free arginine and aspartate, as compared with control tubers were observed.