bluuebunny/crossref_metadata_2025_split huggingface dataset:
A strategy to study tyrosinase transgenes in mouse melanocytes
Authors: Lavado Alfonso , Matheu Ander , Serrano Manuel , Montoliu Lluís 
Published: April 2005

Abstract
Background
A number of transgenic mice carrying different deletions in the Locus Control Region (LCR) of the mouse tyrosinase (Tyr) gene have been developed and analysed in our laboratory. We require melanocytes from these mice, to further study, at the cellular level, the effect of these deletions on the expression of the Tyr transgene, without potential interference with or from the endogenous Tyr alleles. It has been previously reported that it is possible to obtain and immortalise melanocyte cell cultures from postnatal mouse skin.

Results
Here, we describe the efforts towards obtaining melanocyte cultures from our Tyr transgenic mice. We have bred our Tyr transgenic mice into Tyr
c-32DSD
mutant background, lacking the endogenous Tyr locus. In these conditions, we failed to obtain immortalised melanocytes. We decided to include the inactivation of the Ink4a-Arf locus to promote melanocyte immortalisation. For this purpose, we report the segregation of the Ink4a-Arf null allele from the brown (Tyrp1
b
) mutation in mice. Finally, we found that Ink4a-Arf+/- and Ink4a-Arf-/- melanocytes had undistinguishable tyrosine hydroxylase activities, although the latter showed reduced cellular pigmentation content.

Conclusion
The simultaneous presence of precise genomic deletions that include the tyrosinase locus, such as the Tyr
c-32DSD
allele, the Tyr transgene itself and the inactivated Ink4a-Arf locus in Tyrp1
B
genetic background appear as the crucial combination to perform forthcoming experiments. We cannot exclude that Ink4a-Arf mutations could affect the melanin biosynthetic pathway. Therefore, subsequent experiments with melanocytes will have to be performed in a normalized genetic background regarding the Ink4a-Arf locus.
Hepatocyte growth factor (HGF) in fecal samples: rapid detection by surface plasmon resonance
Authors: Nayeri Fariba , Aili Daniel , Nayeri Tayeb , Xu Junyang , Almer Sven , Lundström Ingemar , Åkerlind Britt , Liedberg Bo 
Published: April 2005

Abstract
Background
The development of biosensors, based on surface plasmon resonance (SPR) technology, enables monitoring of a variety of biospecific interactions without the need for chemical-, biological- or radiological-labelled reagents.

Method
We utilised SPR to detect hepatocyte growth factor (HGF) in reconstituted faecal samples and studied samples from patients with infectious gastroenteritis (n = 20) and normal controls (n = 10). Mouse anti-human HGF monoclonal antibodies and recombinant human HGF receptor (c-Met)/Fc chimera were immobilised in flow cells of a CM5 biosensor chip.

Results
We found that infectious gastroenteritis produced a higher signal response compared to controls, due to binding of HGF to monoclonal anti-HGF antibody as well as binding of HGF to c-Met receptor (p < 0.01). The SPR signal response correlated with results from ELISA (r = 72%, p > 0.001). The signal response decreased significantly (p < 0.05) when samples were diluted with dextran, because of reduction in both specific as well as unspecific binding of HGF to dextran. The decrease in the specific response might imply that the dextran- binding site for HGF overlaps with the antibody binding epitope, or that dextran binding induces a conformational change of the HGF molecule. Bands corresponding to HGF were found by gel electrophoresis of purified faeces in an affinity chromatography column immobilised by HGF ligands.

Conclusion
Determination of HGF by SPR might be beneficial in diagnosis of acute situations that present with symptoms of gastroenteritis and may, possibly, guide appropriate medical treatments. This is to our knowledge the first report on the use of SPR for detection of HGF in faeces samples.
Myeloid antigens in childhood lymphoblastic leukemia:clinical data point to regulation of CD66c distinct from other myeloid antigens
Authors: Kalina Tomas , Vaskova Martina , Mejstrikova Ester , Madzo Jozef , Trka Jan , Stary Jan , Hrusak Ondrej 
Published: April 2005

Abstract
Background
Aberrant expression of myeloid antigens (MyAgs) on acute lymphoblastic leukemia (ALL) cells is a well-documented phenomenon, although its regulating mechanisms are unclear. MyAgs in ALL are interpreted e.g. as hallmarks of early differentiation stage and/or lineage indecisiveness. Granulocytic marker CD66c – Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is aberrantly expressed on ALL with strong correlation to genotype (negative in TEL/AML1 and MLL/AF4, positive in BCR/ABL and hyperdiploid cases).

Methods
In a cohort of 365 consecutively diagnosed Czech B-precursor ALL patients, we analyze distribution of MyAg+ cases and mutual relationship among CD13, CD15, CD33, CD65 and CD66c. The most frequent MyAg (CD66c) is studied further regarding its stability from diagnosis to relapse, prognostic significance and regulation of surface expression. For the latter, flow cytometry, Western blot and quantitative RT-PCR on sorted cells is used.

Results
We show CD66c is expressed in 43% patients, which is more frequent than other MyAgs studied. In addition, CD66c expression negatively correlates with CD13 (p < 0.0001), CD33 (p = 0.002) and/or CD65 (p = 0.029). Our data show that different myeloid antigens often differ in biological importance, which may be obscured by combining them into "MyAg positive ALL". We show that unlike other MyAgs, CD66c expression is not shifted from the onset of ALL to relapse (n = 39, time to relapse 0.3–5.3 years). Although opposite has previously been suggested, we show that CEACAM6 transcription is invariably followed by surface expression (by quantitative RT-PCR on sorted cells) and that malignant cells containing CD66c in cytoplasm without surface expression are not found by flow cytometry nor by Western blot in vivo. We report no prognostic significance of CD66c, globally or separately in genotype subsets of B-precursor ALL, nor an association with known risk factors (n = 254).

Conclusion
In contrast to general notion we show that different MyAgs in lymphoblastic leukemia represent different biological circumstances. We chose the most frequent and tightly genotype-associated MyAg CD66c to show its stabile expression in patients from diagnosis to relapse, which differs from what is known on the other MyAgs. Surface expression of CD66c is regulated at the gene transcription level, in contrast to previous reports.
Subjective face recognition difficulties, aberrant sensibility, sleeping disturbances and aberrant eating habits in families with Asperger syndrome
Authors: Nieminen-von Wendt Taina , Paavonen Juulia E , Ylisaukko-Oja Tero , Sarenius Susan , Källman Tiia , Järvelä Irma , von Wendt Lennart 
Published: April 2005

Abstract
Background
The present study was undertaken in order to determine whether a set of clinical features, which are not included in the DSM-IV or ICD-10 for Asperger Syndrome (AS), are associated with AS in particular or whether they are merely a familial trait that is not related to the diagnosis.

Methods
Ten large families, a total of 138 persons, of whom 58 individuals fulfilled the diagnostic criteria for AS and another 56 did not to fulfill these criteria, were studied using a structured interview focusing on the possible presence of face recognition difficulties, aberrant sensibility and eating habits and sleeping disturbances.

Results
The prevalence for face recognition difficulties was 46.6% in individuals with AS compared with 10.7% in the control group. The corresponding figures for subjectively reported presence of aberrant sensibilities were 91.4% and 46.6%, for sleeping disturbances 48.3% and 23.2% and for aberrant eating habits 60.3% and 14.3%, respectively.

Conclusion
An aberrant processing of sensory information appears to be a common feature in AS. The impact of these and other clinical features that are not incorporated in the ICD-10 and DSM-IV on our understanding of AS may hitherto have been underestimated. These associated clinical traits may well be reflected by the behavioural characteristics of these individuals.
Assessing spatio-temporal variability of risk surfaces using residential history data in a case control study of breast cancer
Authors: Han Daikwon , Rogerson Peter A , Bonner Matthew R , Nie Jing , Vena John E , Muti Paola , Trevisan Maurizio , Freudenheim Jo L 
Published: April 2005

AbstractBackgroundMost analyses of spatial clustering of disease have been based on either residence at the time of diagnosis or current residence. An underlying assumption in these analyses is that residence can be used as a proxy for environmental exposure. However, exposures earlier in life and not just those in the most recent period may be of significance. In breast cancer, there is accumulating evidence that early life exposures may contribute to risk. We explored spatio-temporal patterns of risk surfaces using data on lifetime residential history in a case control study of breast cancer, and identified elevated areas of risk and areas potentially having more exposure opportunities, defined as risk surfaces in this study. This approach may be more relevant in understanding the environmental etiology of breast cancer, since lifetime cumulative exposures or exposures at critical times may be more strongly associated with risk for breast cancer than exposures from the recent period.ResultsA GIS-based exploratory spatial analysis was applied, and spatio-temporal variability of those risk surfaces was evaluated using the standardized difference in density surfaces between cases and controls. The significance of the resulting risk surfaces was tested and reported asp-values. These surfaces were compared for premenopausal and postmenopausal women, and were obtained for each decade, from the 1940s to 1990s. We found strong evidence of clustering of lifetime residence for premenopausal women (for cases relative to controls), and a less strong suggestion of such clustering for postmenopausal women, and identified a substantial degree of temporal variability of the risk surfaces.ConclusionWe were able to pinpoint geographic areas with higher risk through exploratory spatial analyses, and to assess temporal variability of the risk surfaces, thus providing a working hypothesis on breast cancer and environmental exposures. Geographic areas with higher case densities need further epidemiologic investigation for potential relationships between lifetime environmental exposures and breast cancer risk. Examination of lifetime residential history provided additional information on geographic areas associated with higher risk; limiting exploration of chronic disease clustering to current residence may neglect important relationships between location and disease.
Breakdown of accommodation in nerve: a possible role for persistent sodium current
Authors: Hennings Kristian , Arendt-Nielsen Lars , Andersen Ole K 
Published: April 2005

Abstract
Background
Accommodation and breakdown of accommodation are important elements of information processing in nerve fibers, as they determine how nerve fibers react to natural slowly changing stimuli or electrical stimulation. The aim of the present study was to elucidate the biophysical mechanism of breakdown of accommodation, which at present is unknown.

Results
A model of a space-clamped motor nerve fiber was developed. It was found that this new model could reproduce breakdown of accommodation when it included a low-threshold, rapidly activating, persistent sodium current. However, the phenomenon was not reproduced when the persistent sodium current did not have fast activation kinetics or a low activation threshold.

Conclusion
The present modeling study suggests that persistent, low-threshold, rapidly activating sodium currents have a key role in breakdown of accommodation, and that breakdown of accommodation can be used as a tool for studying persistent sodium current under normal and pathological conditions.
Monitoring processed, mature Human Immunodeficiency Virus type 1 particles immediately following treatment with a protease inhibitor-containing treatment regimen
Authors: Baird Heather A , Marozsan Andre J , Lederman Michael M , Landay Alan , Mildvan Donna , Kuritzkes Daniel R , Kessler Harold A , Arts Eric J 
Published: April 2005

Abstract
Protease inhibitors (PIs) block HIV-1 maturation into an infectious virus particle by inhibiting the protease processing of gag and gag-pol precursor proteins. We have used a simple anti-HIV-1 p24 Western blot to monitor the processing of p55gag precursor into the mature p24 capsid immediately following the first dosage of a PI-containing treatment regimen. Evidence of PI activity was observed in plasma virus as early as 72 hours post treatment-initiation and was predictive of plasma viral RNA decrease at 4 weeks.
Peer influences on body dissatisfaction and dieting awareness in young girls
Authors: Dohnt Hayley K. , Tiggemann Marika 
Published: April 2005

Aim. This study aimed to explore the role of peer influences in the development of body dissatisfaction and dieting awareness in young girls.Method. A sample of 81 girls (aged 5–8 years) were recruited from the first 3 years of formal schooling. Girls were individually interviewed. Body dissatisfaction was assessed by means of figure rating preferences, and dieting awareness by responses to a brief scenario. A number of sources of peer influence were also assessed.Results. Year 2 girls were found to display significantly greater body dissatisfaction than younger girls. All girls, irrespective of age, preferred a similar thin ideal figure. Year level constituted the only significant predictor of dieting awareness, with older girls demonstrating a greater understanding of dieting than younger girls. Importantly, girls' perception of their peers' body dissatisfaction emerged as the strongest predictor of their own level of body dissatisfaction.Conclusions. Body dissatisfaction in girls first emerges during the junior primary school years, between ages 5 and 7 years, and appears to be a function of shared peer norms for thinness.
Role of Amygdalo-Nigral Circuitry in Conditioning of a Visual Stimulus Paired with Food
Authors: Lee Hongjoo J. , Groshek Frank , Petrovich Gorica D. , Cantalini Joseph P. , Gallagher Michela , Holland Peter C. 
Published: April 2005

The amygdala central nucleus (CeA) plays an important part in associative learning. Although most research has focused on functions of its descending projections to brainstem areas involved in autonomic and somatomotor responses, the ascending projections of CeA also play critical roles in learning. For example, a CeA-nigrostriatal pathway is important for acquiring orienting responses (ORs) to conditioned stimuli (CSs) that signal food delivery. In this study, the function of this CeA-nigrostriatal pathway in appetitive conditioning of rats was considered in more detail.In experiment 1, we combined anatomical tracing and methods for detecting neuronal activation to examine whether CeA neurons that project to the substantia nigra pars compacta (SNc) are activated by a visual CS for food. After injection of the retrograde tracer Fluoro-Gold (FG) into SNc, the rats received pairings of a visual CS with food. After a test with the CS alone, the brains were prepared to assess FG labeling and CS-induced Fos expression in CeA with immunohistochemical procedures. Colocalization of Fos and FG in CeA neurons was visualized with confocal-fluorescence microscopy. The CS induced Fos expression in CeA, and a majority of these Fos-positive neurons were also FG positive, indicating activation of the CeA-SNc pathway by the CS. In experiment 2, lesions that disconnected CeA and SNc prevented the acquisition of conditioned ORs but did not affect the acquisition of conditioned food-related responses or the display of unconditioned ORs. These experiments demonstrate a role for amygdalo-nigral circuitry in learned modulation of attention to signals for biologically significant events.
Microchemical Engineering: Components, Plant Concepts, User Acceptance – Part II
Authors: Hessel V. , Löwe H. 
Published: April 2005

AbstractOver the last five years, many activities have focused on the unexploited field of carrying out reactions on small scales. Due to the rapid development of new components, this paper deals with recent developments only in a compressed form. An important point is the analysis of possible plant concepts for microreactors and whether these are a sensible option. Due to the enormous difference in size between the microchannels and the fluid periphery of possible components this is not just a technical question. It touches on the microtechnology concept as a whole. The direction in which the field should be developed and which measures can be taken to influence its development are questions that are addressed here with respect to the big industrial interest in microreactors.
Size Reduction of Metals by Means of Swing‐Hammer Shredders
Authors: Sander S. , Schubert G. 
Published: April 2005

AbstractSize reduction is of cardinal importance in the recycling of scrap and waste. The choice of size reduction machines is critically dependent on the properties and bonding conditions of the components present in the waste or scrap. Shredders have become widely used for the size reduction of various kinds of scrap. Size reduction of metals in shredders requires sufficiently deformation of the pieces of material (bending to compaction) which leads to cracking. Tensile loads con combination with bending and torsion can enlarge the cracks and ultimately lead to break‐up of the pieces of metal.
Catalytic Oxidation of Liquid Methanol as a Heat Source for an Automotive Reformer
Authors: Lindström B. , Pettersson L.J. 
Published: April 2005

AbstractA reactor for catalytically oxidizing liquid methanol has been developed for supplying heat to an automotive reformer. In the tests presented in this paper we show that it is possible to catalytically combust liquid methanol by dispersing the methanol and air by a nebulizer over the catalysts. In the experiments we tested several base and noble metals and found that either platinum or palladium was required at the ignition zone. The tests also showed that it was possible to achieve complete combustion when only 25 % of the catalyst bed contained a noble metal.
Simultaneous Isomerization and Etherification of Isoamylenes with Methanol
Authors: Kiviranta‐Pääkkönen P. , Krause A.O.I. 
Published: April 2005

AbstractThe effect of feed MeOH/2M1B molar ratio on the initial isomerization and etherification rates of 2‐methyl‐1‐butene (2M1B) was studied in a batch reactor. The initial reaction rates for etherification and isomerization increased when the MeOH/2M1B molar ratio decreased. The ratio of etherification and isomerization rate was 2–3 until at lowest initial MeOH/2M1B molar ratio 0.2, where the isomerization rate increased significantly. At MeOH/2M1B molar ratio 0.2 the isomerization reaction rate was twice as high as the etherification reaction rate. Several kinetic formulations were tested to explain this new data and the data obtained in earlier studies. According to the statistics, a kinetic model based on three active sites gave the best fit, but it was discussed that the basic Langmuir‐Hinshelwood mechanism might be more adequate. An improved fit of the Langmuir‐Hinshelwood model was obtained, when a correction factor describing the acceleration of isomerization rate with the molar fraction of 2M1B was added into the kinetic equations.
Structure–Property Correlations in Solid Solutions of (CuI)8P12−xAsx, 2.4≤x≤6.6
Authors: Jayasekera Buddhimathie , Brock Stephanie L. , Lo Andy Y. H. , Schurko Robert W. , Nazri Gholam‐Abbas 
Published: April 2005

AbstractA series of P/As mixed pnicogen phases of composition (CuI)8P12−xAsx, in which x=2.4, 4.2, 4.8, 5.4, and 6.6, have been synthesized and characterized by X‐ray single crystal and powder diffraction, solid‐state NMR spectroscopy, thermal gravimetric analysis, and impedance spectroscopy. These materials are isostructural to (CuI)8P12 and consist of neutral, tubular P/As mixed pnicogen chains associated with CuI and I− ions. The As is distributed throughout the pnicogen chains; however, the “roof” sites of the [P8] cage show preferred occupation by As relative to the other sites. Accordingly, the change in cell volume is not a linear function of the As incorporation. Solid‐state 31P NMR spectroscopy of the 40 % As incorporated sample are consistent with the X‐ray structural model, with extensive broadening due to 31P–75As coupling and site disorder, and a change in the chemical shifts of the resonances due to the As substitution into the lattice. The degree of copper ion site disorder, probed by single‐crystal X‐ray diffraction, increases with increasing As content. Although very little change is observed in the copper ionic conductivity of polycrystalline samples, which ranges from 1.8–5.1×10−6 S cm−1 for (CuI)8P12−xAsx, x=0, 4.2, 5.4; a single crystal (x=4.8) measured along the needle axis has a conductivity of 1.7×10−3 S cm−1 at 128 °C. This represents an order of magnitude improvement in conductivity over (CuI)8P12 at the same temperature.
Copolymerization of Cyclohexene Oxide with CO2 by Using Intramolecular Dinuclear Zinc Catalysts
Authors: Xiao Youli , Wang Zheng , Ding Kuiling 
Published: April 2005

AbstractThe intramolecular dinuclear zinc complexes generated in situ from the reaction of multidentate semi‐azacrown ether ligands with Et2Zn, followed by treatment with an alcohol additive, were found to promote the copolymerization of CO2 and cyclohexene oxide (CHO) with completely alternating polycarbonate selectivity and high efficiency. With this type of novel initiator, the copolymerization could be accomplished under mild conditions at 1 atm pressure of CO2, which represents a significant advantage over most catalytic systems developed for this reaction so far. The copolymerization reaction was demonstrated to be a living process as a result of the narrow polydispersities and the linear increase in the molecular weight with conversion of CHO. In addition, the solid‐state structure of the dinuclear zinc complex was characterized by X‐ray crystal structural analysis and can be considered as a model of the active catalyst. On the basis of the various efforts made to understand the mechanisms of the catalytic reaction, including MALDI‐TOF mass analysis of the copolymers' end‐groups, the effect of alcohol additives on the catalysis and CO2 pressure on the conversion of CHO, as well as the kinetic data gained from in situ IR spectroscopy, a plausible catalytic cycle for the present reaction system is outlined. The copolymerization is initiated by the insertion of CO2 into the ZnOEt bond to afford a carbonate–ester‐bridged complex. The dinuclear zinc structure of the catalyst remains intact throughout the copolymerization. The bridged zinc centers may have a synergistic effect on the copolymerization reaction; one zinc center could activate the epoxide through its coordination and the second zinc atom may be responsible for carbonate propagation by nucleophilic attack by the carbonate ester on the back side of the cis‐epoxide ring to afford the carbonate. The mechanistic implication of this is particularly important for future research into the design of efficient and practical catalysts for the copolymerization of epoxides with CO2.