bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of ENSO in understanding changes in Colombia's annual malaria burden by region, 1960–2006
Authors: Mantilla Gilma , Oliveros Hugo , Barnston Anthony G 
Published: January 2009

Abstract

Background
Malaria remains a serious problem in Colombia. The number of malaria cases is governed by multiple climatic and non-climatic factors. Malaria control policies, and climate controls such as rainfall and temperature variations associated with the El Niño/Southern Oscillation (ENSO), have been associated with malaria case numbers. Using historical climate data and annual malaria case number data from 1960 to 2006, statistical models are developed to isolate the effects of climate in each of Colombia's five contrasting geographical regions.

Methods
Because year to year climate variability associated with ENSO causes interannual variability in malaria case numbers, while changes in population and institutional control policy result in more gradual trends, the chosen predictors in the models are annual indices of the ENSO state (sea surface temperature [SST] in the tropical Pacific Ocean) and time reference indices keyed to two major malaria trends during the study period. Two models were used: a Poisson and a Negative Binomial regression model. Two ENSO indices, two time reference indices, and one dummy variable are chosen as candidate predictors. The analysis was conducted using the five geographical regions to match the similar aggregation used by the National Institute of Health for its official reports.

Results
The Negative Binomial regression model is found better suited to the malaria cases in Colombia. Both the trend variables and the ENSO measures are significant predictors of malaria case numbers in Colombia as a whole, and in two of the five regions. A one degree Celsius change in SST (indicating a weak to moderate ENSO event) is seen to translate to an approximate 20% increase in malaria cases, holding other variables constant.

Conclusion
Regional differentiation in the role of ENSO in understanding changes in Colombia's annual malaria burden during 1960–2006 was found, constituting a new approach to use ENSO as a significant predictor of the malaria cases in Colombia. These results naturally point to additional needed work: (1) refining the regional and seasonal dependence of climate on the ENSO state, and of malaria on the climate variables; (2) incorporating ENSO-related climate variability into dynamic malaria models.
Terameprocol, a methylated derivative of nordihydroguaiaretic acid, inhibits production of prostaglandins and several key inflammatory cytokines and chemokines
Authors: Eads D , Hansen RL , Oyegunwa AO , Cecil CE , Culver CA , Scholle F , Petty ITD , Laster SM 
Published: January 2009

AbstractBackgroundExtracts of the creosote bush,Larrea tridentata, have been used for centuries by natives of western American and Mexican deserts to treat a variety of infectious diseases and inflammatory disorders. The beneficial activity of this plant has been linked to the compound nordihydroguaiaretic acid (NDGA) and its various substituted derivatives. Recently, tetra-O-methyl NDGA or terameprocol (TMP) has been shown to inhibit the growth of certain tumor-derived cell lines and is now in clinical trials for the treatment of human cancer. In this report, we ask whether TMP also displays anti-inflammatory activity. TMP was tested for its ability to inhibit the LPS-induced production of inflammatory lipids and cytokinesin vitro. We also examined the effects of TMP on production of TNF-α in C57BL6/J mice following a sublethal challenge with LPS. Finally, we examined the molecular mechanisms underlying the effects we observed.MethodsRAW 264.7 cells and resident peritoneal macrophages from C57BL6/J mice, stimulated with 1 μg/ml LPS, were used in experiments designed to measure the effects of TMP on the production of prostaglandins, cytokines and chemokines. Prostaglandin production was determined by ELISA. Cytokine and chemokine production were determined by antibody array and ELISA.Western blots, q-RT-PCR, and enzyme assays were used to assess the effects of TMP on expression and activity of COX-2.q-RT-PCR was used to assess the effects of TMP on levels of cytokine and chemokine mRNA.C57BL6/J mice injectedi.p.with LPS were used in experiments designed to measure the effects of TMPin vivo. Serum levels of TNF-α were determined by ELISA.ResultsTMP strongly inhibited the production of prostaglandins from RAW 264.7 cells and normal peritoneal macrophages. This effect correlated with a TMP-dependent reduction in levels of COX-2 mRNA and protein, and inhibition of the enzymatic activity of COX-2.TMP inhibited, to varying degrees, the production of several cytokines, and chemokines from RAW 264.7 macrophages and normal peritoneal macrophages. Affected molecules included TNF-α and MCP-1. Levels of cytokine mRNA were affected similarly, suggesting that TMP is acting to prevent gene expression.TMP partially blocked the production of TNF-α and MCP-1in vivoin the serum of C57BL6/J mice that were challengedi.p. with LPS.ConclusionTMP inhibited the LPS-induced production of lipid mediators and several key inflammatory cytokines and chemokines, bothin vitroandin vivo, raising the possibility that TMP might be useful as a treatment for a variety of inflammatory disorders.
Removal of spermatozoa with externalized phosphatidylserine from sperm preparation in human assisted medical procreation: effects on viability, motility and mitochondrial membrane potential
Authors: de Vantéry Arrighi Corinne , Lucas Hervé , Chardonnens Didier , de Agostini Ariane 
Published: January 2009

AbstractBackgroundExternalization of phosphatidylserine (EPS) occurs in apoptotic-like spermatozoa and could be used to remove them from sperm preparations to enhance sperm quality for assisted medical procreation. We first characterized EPS in sperms from infertile patients in terms of frequency of EPS spermatozoa as well as localization of phosphatidylserine (PS) on spermatozoa. Subsequently, we determined the impact of depleting EPS spermatozoa on sperm quality.MethodsEPS were visualized by fluorescently-labeled annexin V binding assay. Double staining with annexin V and Hoechst differentiates apoptotic from necrotic spermatozoa. We used magnetic-activated cell sorting using annexin V-conjugated microbeads (MACS-ANMB) technique to remove EPS spermatozoa from sperm prepared by density gradient centrifugation (DGC). The impact of this technique on sperm quality was evaluated by measuring progressive motility, viability, and the integrity of the mitochondrial membrane potential (MMP) by Rhodamine 123.ResultsMean percentages of EPS spermatozoa were 14% in DGC sperm. Four subpopulations of spermatozoa were identified: 70% alive, 3% early apoptotic, 16% necrotic and 11% late apoptotic or necrotic. PS were localized on head and/or midpiece or on the whole spermatozoa. MACS efficiently eliminates EPS spermatozoa. MACS combined with DGC allows a mean reduction of 70% in EPS and of 60% in MMP-disrupted spermatozoa with a mean increase of 50% in sperm survival at 24 h.ConclusionHuman ejaculates contain EPS spermatozoa which can mostly be eliminated by DGC plus MACS resulting in improved sperm long term viability, motility and MMP integrity. EPS may be used as an indicator of sperm quality and removal of EPS spermatozoa may enhance fertility potential in assisted medical procreation.
Semi-allogeneic vaccines and tumor-induced immune tolerance
Authors: Yu Jin , Kindy Mark S , Gattoni-Celli Sebastiano 
Published: January 2009

AbstractExperimental results from studies with inbred mice and their syngeneic tumors indicated that the inoculation of semi-allogeneic cell hybrids (derived from the fusion between syngeneic tumor cells and an allogeneic cell line) protects the animal host from a subsequent lethal challenge with unmodified syngeneic tumor cells. Semi-allogeneic somatic cell hybrids were generated by the fusion of EL-4 T lymphoma cells (H-2b) and BALB/c-derived renal adenocarcinoma RAG cells (H-2d). Cell hybrids were injected intra-peritoneally (i.p.) in C57BL/6 mice (H-2b) before challenging the mice with a tumorigenic dose of EL-4 cells. Semi-allogeneic tumor cell hybrids could not form a tumor in the animal host because they expressed allogeneic determinants (H-2d) and were rejected as a transplant. However, they conferred protection against a tumorigenic challenge of EL-4 cells compared to control mice that were mock-vaccinated with i.p.-injected phosphate-buffered saline (PBS) and in which EL-4 lymphomas grew rapidly to a large size in the peritoneal cavity. Screening of spleen-derived RNA by means of focused microarray technology showed up-regulation of genes involved in the Th-1-type immune response and in the activation of dendritic antigen-presenting cells (APC). The results of our studies confirm the role of APC in mediating the immune protection induced by semi-allogeneic vaccines by activating a Th-1 response; these studies also reveal that semi-allogeneic vaccines are able to interfere with or even block the tumor-mediated induction of immune tolerance, a key mechanism underlying the suppression of anti-tumor immunity in the immune competent host.
Faecal shedding and strain diversity of Listeria monocytogenesin healthy ruminants and swine in Northern Spain
Authors: Esteban Jon I , Oporto Beatriz , Aduriz Gorka , Juste Ramón A , Hurtado Ana 
Published: January 2009

Abstract

Background

Listeria monocytogenes is among the most important foodborne bacterial pathogens due to the high mortality rate and severity of the infection. L. monocytogenes is a ubiquitous organism occasionally present in the intestinal tract of various animal species and faecal shedding by asymptomatically infected livestock poses a risk for contamination of farm environments and raw food at the pre-harvest stages. The aim of this study was to determine the prevalence and strain diversity of L. monocytogenes in healthy ruminants and swine herds.

Results
Faecal samples from 30 animals per herd were collected from 343 herds (120 sheep, 124 beef cattle, 82 dairy cattle and 17 swine) in the Basque Country and screened in pools by an automated enzyme-linked fluorescent immunoassay (VIDAS®) to estimate the prevalence of positive herds. Positive samples were subcultured onto the selective and differential agar ALOA and biochemically confirmed. L. monocytogenes was isolated from 46.3% of dairy cattle, 30.6% beef cattle and 14.2% sheep herds, but not from swine. Within-herd prevalence investigated by individually analysing 197 sheep and 221 cattle detected 1.5% of faecal shedders in sheep and 21.3% in cattle. Serotyping of 114 isolates identified complex 4b as the most prevalent (84.2%), followed by 1/2a (13.2%), and PFGE analysis of 68 isolates showed a highly diverse L. monocytogenes population in ruminant herds.

Conclusion
These results suggested that cattle represent a potentially important reservoir for L. monocytogenes in the Basque Country, and highlighted the complexity of pathogen control at the farm level.
Expression of human papilloma virus type 16 E5 protein in amelanotic melanoma cells regulates endo-cellular pH and restores tyrosinase activity
Authors: Di Domenico Fabio , Foppoli Cesira , Blarzino Carla , Perluigi Marzia , Paolini Francesca , Morici Salvatrice , Coccia Raffaella , Cini Chiara , De Marco Federico 
Published: January 2009

Abstract

Background
Melanin synthesis, the elective trait of melanocytes, is regulated by tyrosinase activity. In tyrosinase-positive amelanotic melanomas this rate limiting enzyme is inactive because of acidic endo-melanosomal pH. The E5 oncogene of the Human Papillomavirus Type 16 is a small transmembrane protein with a weak transforming activity and a role during the early steps of viral infections. E5 has been shown to interact with 16 kDa subunit C of the trans-membrane Vacuolar ATPase proton pump ultimately resulting in its functional suppressions. However, the cellular effects of such an interaction are still under debate. With this work we intended to explore whether the HPV16 E5 oncoprotein does indeed interact with the vacuolar ATPase proton pump once expressed in intact human cells and whether this interaction has functional consequences on cell metabolism and phenotype.

Methods
The expression of the HPV16-E5 oncoproteins was induced in two Tyrosinase-positive amelanotic melanomas (the cell lines FRM and M14) by a retroviral expression construct. Modulation of the intracellular pH was measured with Acridine orange and fluorescence microscopy. Expression of tyrosinase and its activity was followed by RT-PCR, Western Blot and enzyme assay. The anchorage-independence growth and the metabolic activity of E5 expressing cells were also monitored.

Results
We provide evidence that in the E5 expressing cells interaction between E5 and V-ATPase determines an increase of endo-cellular pH. The cellular alkalinisation in turn leads to the post-translational activation of tyrosinase, melanin synthesis and phenotype modulation. These effects are associated with an increased activation of tyrosine analogue anti-blastic drugs.

Conclusion
Once expressed within intact human cells the HPV16-E5 oncoprotein does actually interact with the vacuolar V-ATPase proton pump and this interaction induces a number of functional effects. In amelanotic melanomas these effects can modulate the cell phenotype and can induce a higher sensitivity to tyrosine related anti-blastic drugs.
Superantigen-mediated differentiation of bovine monocytes into dendritic cells
Authors: Seo Keun Seok , Park Joo Youn , Davis William C , Fox Lawrence K , McGuire Mark A , Park Yong Ho , Bohach Gregory A 
Published: January 2009

AbstractAlthough many effects of staphylococcal superantigens (SAg) on T cells are well established, less is known about their effects on APC. In this study, bovine PBMC were stimulated with a low dose of staphylococcal enterotoxin C1 (SEC1). The phenotype of adherent cells (Ac) derived from bovine PBMC cultured with SEC1 [SEC1-stimulated Ac (sAc)] for 192 h was CD14−, CD68−, CD163−, dendritic cell (DC)-specific ICAM-3-grabbing nonintegrin+, MHC class II (MHC II)high, CD11alow, CD11bhigh, CD11chigh, and CD1bhigh, suggesting these cells were dendritic cells (DC). SEC1 also induced transcription of the CXCL1, -2, and -3 family, CXCL6, CCL2, and CCL5 genes in sAc, which increased rapidly but returned to basal levels by 48 h. In contrast, increased transcription of CCL3, CCL8, and CXCL12, responsible for mononuclear cell migration and chronic inflammation, was sustained. In vitro cell migration assays showed vigorous migration of granulocytes, followed by migration of mononuclear cells. The autologous MLR showed that sAc induced a dose-dependent proliferation of CD4+ T cells and an even stronger proliferation of CD8+ T cells. This effect was inhibited or reduced by pretreatment with mAb to CD11b, MHC II, or MHC II plus CD18. These results indicate that stimulation of bovine PBMC by SAg induces differentiation of monocytes into DC.
Sales Growth of New Pharmaceuticals Across the Globe: The Role of Regulatory Regimes
Authors: Stremersch Stefan , Lemmens Aurélie 
Published: January 2009

Prior marketing literature has overlooked the role of regulatory regimes in explaining international sales growth of new products. This paper addresses this gap in the context of new pharmaceuticals (15 new molecules in 34 countries) and sheds light on the effects of regulatory regimes on new drug sales across the globe.Based on a time-varying coefficient model, we find that differences in regulation substantially contribute to cross-country variation in sales. One of the regulatory constraints investigated, i.e., manufacturer price controls, has a positive effect on drug sales. The other forms of regulation such as restrictions of physician prescription budgets and the prohibition of direct-to-consumer advertising (DTCA) tend to hurt sales. The effect of manufacturer price controls is similar for newly launched and mature drugs. By contrast, regulations on physician prescription budgets and DTCA have a differential effect for newly launched and mature drugs. Whereas the former hurts mature drugs more, the latter has a larger effect on newly launched drugs. In addition to these regulatory effects, we find that national culture, economic wealth, and lagged sales also affect drug sales.Our findings may be used as input by managers for international launch and marketing decisions. They may also be used by public policy administrators to assess the role of regulatory regimes in pharmaceutical sales growth.
Findings—Retailer Promotion Pass-Through: A Measure, Its Magnitude, and Its Determinants
Authors: Ailawadi Kusum L. , Harlam Bari A. 
Published: January 2009

We use data on all manufacturer funding and promotion activity by a major U.S. retailer during a two-year period to compute promotion pass-through and assess its magnitude. Then, we estimate a two-tiered probit and lognormal regression model to study drivers of the large variation we observe in pass-through rates. Although our analysis is based on data from a single retailer, it provides a much more complete picture of the magnitude and variability of pass-through than has been available to date. Some key insights from our work are as follows. First, the retailer passes through more than 100% of the total manufacturer funding it receives in aggregate, but the median pass-through rate for individual manufacturers is much lower than 100%. Second, some manufacturers are promoted even without funding. This is more likely for private label and high-share manufacturers in high-lift and high-margin categories. Third, a small number of manufacturer and category characteristics explain a significant amount of the variation in pass-through. In particular, pass-through is higher for private label. It increases with the share of the manufacturer in the focal category but also with the sales of that manufacturer in other categories. Categories with high sales, high promotion lift, low concentration, and low margin get more pass-through. We corroborate some recent conclusions in the literature, e.g., that some pass-through rates are much higher than 100% and that high-share manufacturers get more pass-through. We add several new insights, e.g., on the magnitude of aggregate pass-through, on cross-pass-through across and within categories, on pass-through for private label, and on the category drivers of pass-through.
Cold stress regulation of a bi-functional 3-dehydroquinate dehydratase/shikimate dehydrogenase (DHQ/SDH)-like gene in the freshwater green alga Spirogyra varians
Authors: Han Jong Won , Lee Key Pyoung , Yoon Minchul , Kang Sung Ho , Kim Gwang Hoon 
Published: January 2009

Abstract
A low temperature up-regulated gene was isolated from Spirogyra varians using the differentially expressed gene method. The full cDNA sequence consisted of 1798 bp with an open reading frame of 1560 bp encoding 520 amino acid residues, which had neither a cleavage site nor a signal peptide. The deduced amino acid sequence was highly similar to the bi-functional 3-dehydroquinate dehydratase/shikimate dehydrogenase (DHQ/SDH) gene of higher plants. As the gene was cold regulated, we named it SVCR3 (Spirogyra varians cold regulated gene). SVCR3 had two conserved domains of DHQase I and SDH (AroE), as well as a shikimate-binding site as found in other DHQ/SDH genes. Northern blot analysis showed that SVCR3 was up-regulated at 4°C. When combined with light (>50 μmol photon m-2 s-1) the expression of SVCR3 increased more at 4°C, but the expression was not affected by light intensity alone up to 200 μmol photon m-2 s-1 at temperatures higher than 10°C. Using the zymogram method (which is a visualization method for gel areas containing specific enzymes based on chromogenic reactions), we showed that there were three isozymes of DHQ/SDH in Spirogyra varians. This is the first report of DHQ/SDH-like gene regulation by cold stress.
Dilatometric Analysis for Investigating Age Hardening in a Commercial Precious Metal Dental Alloy
Authors: Rivolta B. , Gerosa R. , Pinasco M. R. , Pellati G. 
Published: January 2009

Abstract
Age hardening in a commercial precious metal dental alloy based on the Au–Cu–Ag system with platinum addition was investigated by light optical microscope, scanning electron microscope, energy dispersion x-ray system microanalysis, image analysis, hardness measurements, and dilatometric tests. Dilatometric tests are known to give important information for optimizing the heat treatment parameters of metallic materials but are seldom used in studying the hardening of precious alloys. Nonisothermal dilatometric tests were used to point out the temperature range within which the microstructural hardening transformations occur, while isothermal tests were adopted to study the kinetics of each transformation. The macrohardness and microhardness measurements contributed to the understanding of the nature of the observed transformations, together with the microstructural analysis. We concluded that hardening is mainly due to order-disorder transformations taking place in the matrix. The identified optimal parameters were used for the heat treatment of a lost wax casting alloy prepared according to the traditional procedures for prosthesis manufacturing.
One More Discussion “What is Intensive Quenching Process?”
Authors: Kobasko N. I. , Aronov M. A. , Powell J. A. , Totten G. E. 
Published: January 2009

Abstract
Three intensive quenching processes known as IQ-1, IQ-2, and IQ-3 are considered. In contrast to IQ-2 and IQ-3, processes that use water as a quenchant, the two-step IQ-1 technique is actually a combination of a conventional quench (in oil or polymer/water solution) as the first step, followed by intensive quenching in water (the second step). Similar to the IQ-2 and IQ-3 methods, the IQ-1 process provides residual surface compressive stresses, optimum hardened depth, and additional strengthening (superstrengthening) of the material. A database and a method of calculating the IQ-1 process parameters are considered. The authors underlined that IQ processes are green environmentally friendly methods that significantly reduce CO2 emissions and energy consumption. Also examples of the use of IQ-2 and IQ-3 methods for quenching different kinds of steel parts (such as shafts, pinions, crosses, etc.) are provided. It is shown that the IQ technology’s rapid and uniform cooling rates increase service life of steel parts due to the creation of high residual compressive stresses at the surface of steel parts and due to additional strengthening (superstrengthening) of the material.
Optimierung der Regelung zwischen Brennstoffzelle und Batterie in Bezug auf KomponentenalterungOptimization of Fuel Cell and Battery Control in Relation to Component Aging of Fuel Cell Power Train
Authors: Herb Frieder , Frank Achim , Nitsche Christof , Jossen Andreas 
Published: January 2009

Zusammenfassung
Der Beitrag untersucht die Einflüsse unterschiedlicher Hybridisierungsstrategien für Brennstoffzellen-Hybrid-Fahrzeuge auf die Lebensdauer der Brennstoffzelle und der Hybrid-Batterie. Hierbei wurde der Wasserstoffverbrauch bei verschiedener Fahrzyklen mit betrachtet. Die Hybridisierungsstrategien konzentrieren sich alleine auf die Regelung der Leistungsverteilung von Brennstoffzelle und Batterie. Die Untersuchung wurde anhand eines erarbeiteten Fahrzeugsimulationsmodells und Fahrzeugdaten aus dem Advisor-Modell durchgeführt. Für die Lebensdauer der Brennstoffzelle und der Batterie wurden Güteparameter definiert und in einem Netz-Diagramm dargestellt. Des Weiteren wurde der Einfluss einer degradierten Brennstoffzelle auf die Regelung untersucht. Dafür wurde ein Brennstoffzellenmodell, auf der Basis künstlicher neuronaler Netze, anhand von realen Fahrdaten erstellt und in das Gesamtfahrzeugmodell eingebunden. Die Veränderung wird mittels der Abhängigkeit der Güteparameter vom Regelungsparameter diskutiert.