bluuebunny/crossref_metadata_2025_split huggingface dataset:
HOW WELL DO DIAGNOSIS‐RELATED GROUPS FOR APPENDECTOMY EXPLAIN VARIATIONS IN RESOURCE USE? AN ANALYSIS OF PATIENT‐LEVEL DATA FROM 10 EUROPEAN COUNTRIES
Authors: Mason Anne , Or Zeynep , Renaud Thomas , Street Andrew , Thuilliez Josselin , Ward Padraic ,   ON BEHALF OF THE EURODRG GROUP
Published: July 2012

ABSTRACTAppendectomy is a common and relatively simple procedure to remove an inflamed appendix, but the rate of appendectomy varies widely across Europe. This paper investigates factors that explain differences in resource use for appendectomy.We analysed 106 929 appendectomy patients treated in 939 hospitals in 10 European countries. In stage 1, we tested the performance of three models in explaining variation in the (log of) cost of the inpatient stay (seven countries) or length of stay (three countries). The first model used only the diagnosis‐related groups (DRGs) to which patients were coded, the second model used a core set of general patient‐level and appendectomy‐specific variables, and the third model combined both sets of variables. In stage two, we investigated hospital‐level variation.In classifying appendectomy patients, most DRG systems take account of complex diagnoses and comorbidities but use different numbers of DRGs (range: 2 to 8). The capacity of DRGs and patient‐level variables to explain patient‐level cost variation ranges from 34% in Spain to over 60% in England and France. All DRG systems can make better use of administrative data such as the patient's age, diagnoses and procedures, and all countries have outlying hospitals that could improve their management of resources for appendectomy. Copyright © 2012 John Wiley & Sons, Ltd.
PATIENT CLASSIFICATION AND HOSPITAL COSTS OF CARE FOR STROKE IN 10 EUROPEAN COUNTRIES
Authors: Peltola Mikko ,   on behalf of the EuroDRG group
Published: July 2012

ABSTRACTStroke is a major cause of death and disability around the world, and the care of stroke patients ties up a great amount of resources in healthcare systems. Stroke severity and the given care may vary substantially between patients, and there is remarkable variation in both the costs and length of stay (LoS) of stroke patients.Using patient level data from 10 European countries on costs and LoS, we explored the ability of the diagnosis‐related group (DRG) systems to explain variance in the costs and length of stay of stroke patients. In addition, we evaluated whether the existing DRGs for stroke patients would benefit from additional patient‐related and treatment‐related factors that are commonly found in the administrative databases across countries. Cost analyses were run using OLS fixed effects models, and LoS analyses with negative binomial models.The descriptive statistics showed that the stroke patients differ remarkably across countries. Large variations in the classification of stroke patients raise concerns about whether all systems rely on the most appropriate classification variables. In all the countries, the DRG classifications' performance could be improved with the introduction of the patient characteristics analysed here. Copyright © 2012 John Wiley & Sons, Ltd.
DO DIAGNOSIS‐RELATED GROUPS APPROPRIATELY EXPLAIN VARIATIONS IN COSTS AND LENGTH OF STAY OF HIP REPLACEMENT? A COMPARATIVE ASSESSMENT OF DRG SYSTEMS ACROSS 10 EUROPEAN COUNTRIES
Authors: Geissler Alexander , Scheller‐Kreinsen David , Quentin Wilm ,   on behalf of the EuroDRG group
Published: July 2012

ABSTRACTThis paper assesses the variations in costs and length of stay for hip replacement cases in Austria, England, Estonia, Finland, France, Germany, Ireland, Poland, Spain and Sweden and examines the ability of national diagnosis‐related group (DRG) systems to explain the variation in resource use against a set of patient characteristic and treatment specific variables. In total, 195 810 cases clustered in 712 hospitals were analyzed using OLS fixed effects models for cost data (n = 125 698) and negative binominal models for length‐of‐stay data (n = 70 112). The number of DRGs differs widely across the 10 European countries (range: 2–14). Underlying this wide range is a different use of classification variables, especially secondary diagnoses and treatment options are considered to a different extent. In six countries, a standard set of patient characteristics and treatment variables explain the variation in costs or length of stay better than the DRG variables. This raises questions about the adequacy of the countries' DRG system or the lack of specific criteria, which could be used as classification variables. Copyright © 2012 John Wiley & Sons, Ltd.
Glycogen synthase kinase 3-mediated voltage-dependent anion channel phosphorylation controls outer mitochondrial membrane permeability during lipid accumulation
Authors: Martel Cecile , Allouche Maya , Esposti Davide Degli , Fanelli Elena , Boursier Céline , Henry Céline , Chopineau Joel , Calamita Giuseppe , Kroemer Guido , Lemoine Antoinette , Brenner Catherine 
Published: July 2012

Abstract
Nonalcoholic steatosis is a liver pathology characterized by fat accumulation and severe metabolic alterations involving early mitochondrial impairment and late hepatocyte cell death. However, mitochondrial dysfunction mechanisms remain elusive. Using four models of nonalcoholic steatosis, i.e., livers from patients with fatty liver disease, ob/ob mice, mice fed a high-fat diet, and in vitro models of lipotoxicity, we show that outer mitochondrial membrane permeability is altered and identified a posttranslational modification of voltage-dependent anion channel (VDAC), a membrane channel and NADH oxidase, as a cause of early mitochondrial dysfunction. Thus, in nonalcoholic steatosis VDAC exhibits reduced threonine phosphorylation, which increases the influx of water and calcium into mitochondria, sensitizes the organelle to matrix swelling, depolarization, and cytochrome c release without inducing cell death. This also amplifies VDAC enzymatic and channel activities regulation by calcium and modifies its interaction with proteic partners. Moreover, lipid accumulation triggers a rapid lack of VDAC phosphorylation by glycogen synthase kinase 3 (GSK3). Pharmacological and genetic manipulations proved GSK3 to be responsible for VDAC phosphorylation in normal cells. Notably, VDAC phosphorylation level correlated with steatosis severity in patients. Conclusion: VDAC acts as an early sensor of lipid toxicity and its GSK3-mediated phosphorylation status controls outer mitochondrial membrane permeabilization in hepatosteatosis. (Hepatology 2013)
Increased functional connectivity within medial temporal lobe in mild cognitive impairment
Authors: Das Sandhitsu R. , Pluta John , Mancuso Lauren , Kliot Dasha , Orozco Sylvia , Dickerson Bradford C. , Yushkevich Paul A. , Wolk David A. 
Published: July 2012

AbstractPathology at preclinical and prodromal stages of Alzheimer's disease (AD) may manifest itself as measurable functional change in neuronal networks earlier than detectable structural change. Functional connectivity as measured using resting‐state functional magnetic resonance imaging has emerged as a useful tool for studying disease effects on baseline states of neuronal networks. In this study, we use high resolution MRI to label subregions within the medial temporal lobe (MTL), a site of early pathology in AD, and report an increase in functional connectivity in amnestic mild cognitive impairment between entorhinal cortex and subregions of the MTL, with the strongest effect in the anterior hippocampus. However, our data also replicated the effects of decreased connectivity of the MTL to other nodes of the default mode network reported by other researchers. This dissociation of changes in functional connectivity within the MTL versus the MTL's connection with other neocortical structures can help enrich the characterization of early stages of disease progression in AD. © 2012 Wiley Periodicals, Inc.
Hyperforin modulates dendritic spine morphology in hippocampal pyramidal neurons by activating Ca2+‐permeable TRPC6 channels
Authors: Leuner Kristina , Li Wei , Amaral Michelle D. , Rudolph Stephanie , Calfa Gaston , Schuwald Anita M. , Harteneck Christian , Inoue Takafumi , Pozzo‐Miller Lucas 
Published: July 2012

AbstractThe standardized extract of the St. John's wort plant (Hypericum perforatum) is commonly used to treat mild to moderate depression. Its active constituent is hyperforin, a phloroglucinol derivative that reduces the reuptake of serotonin and norepinephrine by increasing intracellular Na+ concentration through the activation of nonselective cationic TRPC6 channels. TRPC6 channels are also Ca2+‐permeable, resulting in intracellular Ca2+ elevations. Indeed, hyperforin activates TRPC6‐mediated currents and Ca2+ transients in rat PC12 cells, which induce their differentiation, mimicking the neurotrophic effect of nerve growth factor. Here, we show that hyperforin modulates dendritic spine morphology in CA1 and CA3 pyramidal neurons of hippocampal slice cultures through the activation of TRPC6 channels. Hyperforin also evoked intracellular Ca2+ transients and depolarizing inward currents sensitive to the TRPC channel blocker La3+, thus resembling the actions of the neurotrophin brain‐derived neurotrophic factor (BDNF) in hippocampal pyramidal neurons. These results suggest that the antidepressant actions of St. John's wort are mediated by a mechanism similar to that engaged by BDNF. © 2012 Wiley Periodicals, Inc.
Preoperative serum tissue polypeptide‐specific antigen is a valuable prognostic marker in breast cancer
Authors: Ahn Soo Kyung , Moon Hyeong‐Gon , Ko Eunyoung , Kim Han Suk , Shin Hee‐Chul , Kim Jisun , You Jee Man , Han Wonshik , Noh Dong‐Young 
Published: July 2012

AbstractTissue polypeptide‐specific antigen (TPS), a specific epitope structure of a peptide in serum associated with human cytokeratin 18, is linked to the proliferative activity of tumors. Here, we aimed to identify the association between the preoperative serum TPS level and outcome in breast cancer patients. We assayed preoperative serum TPS levels in 1,477 breast cancer patients treated between June 2000 and December 2006. The TPS level was measured with a one‐step solid phase radiometric sandwich assay detecting the M3 epitope on cytokeratin 18 fragments. The cutoff value was 80 U/L. Among the 1,477 breast cancer patients examined, preoperative serum TPS level was elevated (>80 U/L) in 290 patients (19.6%). Age (>45 years), tumor size (>2 cm), nodal metastasis, negative progesterone receptor and human epidermal growth factor receptor 2 were associated with elevated TPS. Evidence of recurrence was observed in 229 patients (15.6%). Elevated TPS was associated with poor disease‐free survival (p < 0.001) and overall survival (p < 0.001). In a multivariate analysis using the Cox proportional regression model, elevated TPS was an independent prognostic factor for disease‐free survival (p = 0.001) and overall survival (p = 0.026). Furthermore, in subgroup analysis based on molecular subtype, the prognostic effect of preoperative TPS on survival (OS: HR 2.614, p = 0.003; DFS: HR 1.895, p = 0.001) was identified only in the luminal A subtype. Elevated preoperative serum TPS level is associated with poor breast cancer outcomes. Based on these findings, we conclude that preoperative TPS is a valuable biomarker for clinical use in predicting outcomes in breast cancer patients.
Prognostic value of arginase‐II expression and regulatory T‐cell infiltration in head and neck squamous cell carcinoma
Authors: Bron Luc , Jandus Camilla , Andrejevic‐Blant Snezana , Speiser Daniel E. , Monnier Philippe , Romero Pedro , Rivals Jean‐Paul 
Published: July 2012

AbstractTumor‐infiltrating lymphocytes are present in a variety of tumors and play a central role in antitumor immune responses. Nevertheless, most cancers progress probably because tumors are only weakly immunogenic and develop multiple immunosuppressive mechanisms. In the present study, on head and neck squamous cell carcinoma, we found high intraepithelial infiltration of regulatory FOXP3+T cells, and relatively high levels of BDCA2+and FOXP3+cells in stromal (peripheral) regions of the tumors. Tumor‐infiltrating (intraepithelial) FOXP3+T cells were significantly more frequent in patients with oropharynx and oral cavity squamous cell carcinoma and in patients without lymph node metastasis. Furthermore, arginase‐II (ARG2) was expressed by 60%, inducible nitric oxide synthetase by 9%, cyclooxygenase‐2 by 43%, and B‐cell lymphoma 2 (BCL2) by 26% of tumors. Interestingly, the absence of ARG2 expression, enhanced stromal infiltration of CD11c+myeloid dendritic cells, and high numbers of FOXP3+T cells were each significantly associated with prolonged overall survival, and the latter two parameters were also confirmed by multivariate analysis. For disease‐free survival, multivariate analysis revealed significant negative correlations with BCL2 and ARG2 expression by tumor cells. These findings shed new light on mechanisms of cancer progression, and provide rationales for therapeutic inhibition of immunosuppressive mechanisms in head and neck squamous cell carcinoma.
Early childhood infection of Kaposi's sarcoma‐associated herpesvirus in Zambian households: A molecular analysis
Authors: Olp Landon N. , Shea Danielle M. , White Maxine K. , Gondwe Clement , Kankasa Chipepo , Wood Charles 
Published: July 2012

AbstractSub‐Saharan Africa is endemic for Kaposi's sarcoma‐associated herpesvirus (KSHV) and there is a high rate of early childhood infection; however, the transmission sources are not well characterized. We examined household members as potential KSHV transmission sources to young children in the KSHV‐endemic country of Zambia. To this end, we enrolled and followed Zambian households with at least one KSHV‐seropositive child and collected longitudinal buccal swab samples. KSHV burden was evaluated and K1 sequences from the children were determined and analyzed for differences to K1 sequences from household members. The K1 sequences were also analyzed for evolution over time. We generated K1 sequences from 31 individuals across 16 households. Nine households contained multiple KSHV‐positive members, including at least one child. In six out of the nine households, the child had 100% sequence identity to all household members. However, in two households the child and mother had distinct K1 sequences. In the remaining household, the children were the only KSHV‐infected individuals. Furthermore, we report that 1 out of 18 individuals had K1 sequence variation within the timespan analyzed. In our study, we provide evidence that (i) early childhood KSHV transmission occurs from both within and outside the household, (ii) intrahousehold transmission can occur via nonmaternal sources, (iii) viral shedding in the buccal cavity is highly variable and (iv) the dominant K1 sequence within an individual did not rapidly evolve over time. These results are important for developing KSHV intervention strategies.
Inhibition of rhabdomyosarcoma cell and tumor growth by targeting specificity protein (Sp) transcription factors
Authors: Chadalapaka Gayathri , Jutooru Indira , Sreevalsan Sandeep , Pathi Satya , Kim Kyounghyun , Chen Candy , Crose Lisa , Linardic Corinne , Safe Stephen 
Published: July 2012

AbstractSpecificity protein (Sp) transcription factors Sp1, Sp3 and Sp4 are highly expressed in rhabdomyosarcoma (RMS) cells. In tissue arrays of RMS tumor cores from 71 patients, 80% of RMS patients expressed high levels of Sp1 protein, whereas low expression of Sp1 was detected in normal muscle tissue. The non‐steroidal anti‐inflammatory drug (NSAID) tolfenamic acid (TA) inhibited growth and migration of RD and RH30 RMS cell lines and also inhibited tumor growth in vivo using a mouse xenograft (RH30 cells) model. The effects of TA were accompanied by downregulation of Sp1, Sp3, Sp4 and Sp‐regulated genes in RMS cells and tumors, and the role of Sp protein downregulation in mediating inhibition of RD and RH30 cell growth and migration was confirmed by individual and combined knockdown of Sp1, Sp3 and Sp4 proteins by RNA interference. TA treatment and Sp knockdown in RD and RH30 cells also showed that four genes that are emerging as individual drug targets for treating RMS, namely c‐MET, insulin‐like growth factor receptor (IGFR), PDGFRα and CXCR4, are also Sp‐regulated genes. These results suggest that NSAIDs such as TA may have potential clinical efficacy in drug combinations for treating RMS patients.
Vibrational frequency scale factors for density functional theory and the polarization consistent basis sets
Authors: Laury Marie L. , Carlson Matthew J. , Wilson Angela K. 
Published: July 2012

AbstractCalculated harmonic vibrational frequencies systematically deviate from experimental vibrational frequencies. The observed deviation can be corrected by applying a scale factor. Scale factors for: (i) harmonic vibrational frequencies [categorized into low (<1000 cm−1) and high (>1000 cm−1)], (ii) vibrational contributions to enthalpy and entropy, and (iii) zero‐point vibrational energies (ZPVEs) have been determined for widely used density functionals in combination with polarization consistent basis sets (pc‐n, n = 0,1,2,3,4). The density functionals include pure functionals (BP86, BPW91, BLYP, HCTH93, PBEPBE), hybrid functionals with Hartree‐Fock exchange (B3LYP, B3P86, B3PW91, PBE1PBE, mPW1K, BH&HLYP), hybrid meta functionals with the kinetic energy density gradient (M05, M06, M05‐2X, M06‐2X), a double hybrid functional with Møller‐Plesset correlation (B2GP‐PLYP), and a dispersion corrected functional (B97‐D). The experimental frequencies for calibration were from 41 organic molecules and the ZPVEs for comparison were from 24 small molecules (diatomics, triatomics). For this family of basis sets, the scale factors for each property are more dependent on the functional selection than on basis set level, and thus allow for a suggested scale factor for each density functional when employing polarization consistent basis sets (pc‐n, n = 1,2,3,4). A separate scale factor is recommended when the un‐polarized basis set, pc‐0, is used in combination with the density functionals. © 2012 Wiley Periodicals, Inc.
Calculating pKa values for substituted phenols and hydration energies for other compounds with the first‐order fuzzy‐border continuum solvation model
Authors: Sharma Ity , Kaminski George A. 
Published: July 2012

AbstractWe have computed pKa values for 11 substituted phenol compounds using the continuum Fuzzy‐Border (FB) solvation model. Hydration energies for 40 other compounds, including alkanes, alkenes, alkynes, ketones, amines, alcohols, ethers, aromatics, amides, heterocycles, thiols, sulfides, and acids have been calculated. The overall average unsigned error in the calculated acidity constant values was equal to 0.41 pH units and the average error in the solvation energies was 0.076 kcal/mol. We have also reproduced pKa values of propanoic and butanoic acids within about 0.1 pH units from the experimental values by fitting the solvation parameters for carboxylate ion carbon and oxygen atoms. The FB model combines two distinguishing features. First, it limits the amount of noise which is common in numerical treatment of continuum solvation models by using fixed‐position grid points. Second, it uses either second‐ or first‐order approximation for the solvent polarization, depending on a particular implementation. These approximations are similar to those used for solute and explicit solvent fast polarization treatment which we developed previously. This article describes results of using the first‐order technique. This approximation places the presented methodology between the Generalized Born and Poisson‐Boltzmann continuum solvation models with respect to their accuracy of reproducing the many‐body effects in modeling a continuum solvent. © 2012 Wiley Periodicals, Inc.
Observed changes and trends in numbers of summer and tropical days, and the 2010 hot summer in Turkey
Authors: Erlat Ecmel , Türkeş Murat 
Published: July 2012

AbstractLong‐term variability and trends of the annual numbers of summer and tropical days were investigated by using nonlinear (monotonic) and linear trend detection tests for the period 1950–2010 for 97 meteorological stations of Turkey. The results suggest that the numbers of both summer and tropical days indicate a general increasing tendency in Turkey. For the study period, statistically significant increasing trends for summer (tropical) days are detected at 64 (71) stations, of which 51 (58) of these positive trends are significant at the 0.01 significance level. Two periods of changes in summer and tropical days are identified: in the 1950–1975 sub‐period with an episode of slight cooling, the annual number of summer and tropical days decreases, whereas in the sub‐period of 1976–2010 with an episode of significant increasing trend, the annual number of summer and tropical days increases. The summer of 2010 was exceptional for the number of summer and tropical days at most of the stations in Turkey. Normalized anomalies of summer (tropical) days at 2010 were larger than three standard deviations with respect to 1961–1990 normal at 27 (43) stations. The largest positive anomalies are observed in the northeastern Anatolia sub‐region. This increasing trend has significant impacts on agriculture, energy, tourism and natural ecosystems (e.g., forest fires) in Turkey. Copyright © 2012 Royal Meteorological Society
Artificial Niches: Biomimetic Materials for Hematopoietic Stem Cell Culture
Authors: Lee‐Thedieck Cornelia , Spatz Joachim P. 
Published: July 2012

AbstractHematopoietic stem cells (HSCs) are indispensable for the treatment of patients with hematological disorders such as leukemia. However, the amount of available transplantable HSCs is limited. Therefore, new approaches to multiply HSCs in the laboratory are needed. Promising biomimetic technologies for HSC expansion are currently developed. This feature article gives an insight into the significance of this approach and introduces the essential building blocks (cells, matrix, and scaffolds) of biomimetic materials. Some recent strategies are highlighted and the challenges and possible applications of such materials are discussed.
Design and thermoregulation of a new microextrusion dispense head for 3D‐plotting of thermally sensitive thermoplastics
Authors: Ragaert K. , De Baere I. , Moerman M. , Cardon L. , Degrieck J. 
Published: July 2012

AbstractThree‐dimensional plotting of micro‐extruded filaments is a promising method for the manufacture of porous structures in thermoplastic polymers. However, it has been noted that conventional dispense head systems for this microextrusion are unsuitable for the reliable processing of thermally sensitive polymers like poly(lactic acid) (PLA): the batch polymer remains in the molten state prior to processing and it will degrade under this thermal load, leading to polymer chain reduction. Therefore, a new dispense head system was developed which thermally separates a cold material supply zone from the hot extrusion zone and allows for the processing of PLA‐based polymers without severe degradation. This manuscript discusses the design of the new dispense head and compares its thermoregulation with that of a conventional system by means of finite element modeling and infrared imaging. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers