bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perfusionists in the world of tissue engineering — a quick and easy method for safe isolation of huge quantities of porcine cardiomyocytes
Authors: Neumann Bernd , Guo Ketai , Paul Angela , Greiner Tim O. , Graessle Angelika , Walter Christian , Walker Tobias , Scheule Albertus , Ziemer Gerhard , Wendel Hans P. 
Published: June 2007

Isolation of huge quantities of primary cells from whole organs like the heart becomes increasingly important, especially for the emerging research field of tissue engineering and regenerative medicine. This study deals with the isolation of pig cardiomyocytes, in contrast to the standard mouse or rat models, because we aimed to draw attention to the species, which are genetically more closely related to the human organism. The bigger operative and veterinary expenditure of the pig-heart model can only be justified by a technique that supplies a big amount of qualitative high-grade cardiomyocytes. In our model, the quality is guaranteed by protection of the heart, already in situ, by a cardioplegia and a careful application of collagenase to soften the tissue. The construction of a new apparatus which includes enormous costs was not necessary, since the perfusion equipment was realized from two commercially available HLMsets, which were modified and connected to each other. Our model makes it possible to rinse the whole myocardium, which leads to a better output than models that only prepare a part of the myocardium around a coronary artery. The careful harvesting of high-grade cardiomyocytes is an important source of successful cell cultures to be used for numerous experimental applications, may reduce animal experiments and, additionally, represents a chance for perfusionists to become an important partner in interdisciplinary research projects. Perfusion (2007) 22, 137—142.
Tissue and plasma concentrations of cephuroxime during cardiac surgery in cardiopulmonary bypass — a microdialysis study
Authors: Mand'ák J. , Pojar M. , Maláková J. , Lonsky V. , Palička V. , Zivný P. 
Published: June 2007

Aim: Wound and mediastinal infections are still very serious complications of open-heart surgery, in spite of the use of prophylactic antibiotics. The use of cardiopulmonary bypass (CPB) is associated with profound physiological changes affecting the pharmacokinetic behaviour of antibiotics. The aim of this pilot study was to monitor the tissue concentrations of cephuroxime (prophylactic antibiotic) in skeletal muscle during cardiac surgery using CPB by interstitial microdialysis. These concentrations were compared with plasma concentrations of cephuroxime. Material and methods: Nine adult patients operated on using CPB were enrolled in this study. Cephuroxime was used as a prophylactic antibiotic (1st dose — 3 g of cefuroxime i.v. with anesthesia induction, 2nd dose — 1.5 g i.v. after CPB with protamine sulphate, 3rd dose — 1.5 g i.v. 8 hours after the surgery). Interstitial microdialysis was performed by probe CMA 60 (CMA Microdialysis AB, Sweden) inserted into the patient's deltoid muscle. Concentrations of cephuroxime in dialysates and in plasma were determined by the modified fluid chromatography method. The unbound cephuroxime fraction in plasma was obtained by using an ultrafiltration method. Samples of dialysates were collected at the following intervals: before CPB, each 30 minutes of CPB, at the end of CPB. Samples of blood were collected at these intervals: incision, start of CPB, each 30 minutes of CPB, at the end of CPB, at the end of surgery. Concentrations of cephuroxime in tissue were corrected by in vivo recoveries of the microdialysis probes. Results: Plasma concentrations of cephuroxime were 163.5 ± 40.1, 79.3 ± 17.4, 73.7 ± 16.8, 66.1 ± 18.3, 57.0 ± 10.9, 120.7 ± 29.9 (mg . L—1) and concentrations of free plasma fraction of cephuroxime were 119.5 ± 35.2, 67.8 ± 15.5, 66.0 ± 12.5, 54.8 ± 12.2, 49.6 ± 9.8, 102.6 ± 26.0 (mg . L—1). The concentrations of cephuroxime in dialysates were 44.3 ± 15.7, 36.1 ± 11.6, 31.9 ± 9.3, 34.6 ± 12.3, 27.6 ± 12.9, 56.7 ± 17.6 (mg . L—1). The mean in vivo recovery of cephuroxime in this study was 30%. Corrected concentrations (calculated by in vivo recovery) of cephuroxime in skeletal muscle were 148, 120, 106, 115, 92, 189 (mg . L—1). Conclusion: Our preliminary results show that CPB can modify the time course of cephuroxime plasma and tissue concentrations. A decrease in plasma drug concentrations occurred at the start of CPB and lasted until CPB ended. An increase in plasma concentrations corresponds to the second drug dose after CPB. The concentrations of cephuroxime in skeletal muscle (corrected by recovery) during CPB are higher than plasma concentrations. It is influenced by important changes during CPB; closely associated with hemodilution, a shift of intravascular volume, solutes and albumin to the extravascular space and inconstant protein binding of cephuroxime during operation. Perfusion (2007) 22, 129—136.
Relationships between Productivity, Physical Habitat, and Aquatic Invertebrate and Vertebrate Populations of Forest Streams: An Information‐Theoretic Approach
Authors: Kiffney P. M. , Roni P. 
Published: June 2007

AbstractFreshwater ecosystems worldwide are threatened by habitat degradation resulting in widespread population declines or extinction of invertebrate and vertebrate taxa. Millions of dollars are spent annually on efforts to restore the physical complexity of degraded habitats, such as adding wood to streams. The efficacy of these efforts may be limited, however, because basal productivity (availability of nutrients, algae, bacteria, and organic matter) and predation also constrain the abundance and diversity of stream biota. Using light input as a surrogate for basal productivity, we examined the relative importance of predation, productivity, and physical habitat in explaining the variation in invertebrate and vertebrate populations in small forest streams of coastal Oregon. Our results suggest that aquatic populations are limited by these factors individually and in combination as well as by their interactive effects. For example, invertebrate taxa richness was best predicted by basal productivity, and richness was positively correlated with light. Total vertebrate biomass was positively related to both basal productivity and physical habitat, and the top‐ranked model included light input and velocity. The top‐ranked model explaining variation in the biomass of the coastal giant salamander Dicamptodon tenebrosus was a single‐variable model that included the interaction of basal productivity with channel slope. Streams are dynamic environments, and species living within these ecosystems are probably affected by multiple, interacting factors. Our results support this notion and suggest that, in some cases, restoring physical habitat may have minimal effect on stream communities if productivity at lower trophic levels is also limiting.
Morphological variation in the Weberian apparatus of Cypriniformes
Authors: Bird Nathan C. , Hernandez L. Patricia 
Published: June 2007

AbstractCypriniformes (which includes the minnows, carps, loaches, algae‐eaters, stone loaches, and suckers) is a morphologically diverse and incredibly speciose order of teleosts. It has been suggested that a number of evolutionary innovations, key to improved hearing and feeding, have played an important role in cypriniform fishes' success. One such innovation, the Weberian apparatus, is a novel assemblage of vertebral elements and modified ribs that relay and amplify sound pressure changes from the gas bladder to the inner ear. The Weberian apparatus unites Cypriniformes with other major orders into an extremely species‐rich group of fishes, the Otophysi. Together, otophysan fishes comprise one of the largest groups of fishes in the world, as well as the majority of freshwater fishes. Here we present a detailed comparison of the Weberian apparatus in a number of cypriniform families using cleared and stained specimens. We present data regarding inter‐ and intrafamilial morphological variation within Cypriniformes. With few, but evolutionarily important, exceptions we find that diagnostic features of the Weberian apparatus characterize each family. Interspecific variation within each of the families Balitoridae, Gyrinocheilidae, and Catostomidae is only slight, whereas variation among subfamilies within Cyprinidae and Cobitidae is far more significant. This comparative study identifies a number of distinct morphologies, some of which appear highly correlated with ecological niche. For example, inhabiting swift‐moving waters appears to be a key factor in the encapsulation of the anterior gas bladder in some cobitids, balitorids, and gobionin cyprinids. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.
Skeletal muscle fiber type conversion during the repair of mouse soleus: Potential implications for muscle healing after injury
Authors: Matsuura Tetsuya , Li Yong , Giacobino Jean‐Paul , Fu Freddie H. , Huard Johnny 
Published: June 2007

AbstractWe used a mouse model of cardiotoxin injury to examine fiber type conversion during muscle repair. We evaluated the soleus muscles of 37 wild‐type mice at 2, 4, 8, and 12 weeks after injury. We also used antibodies (fMHC and sMHC) against fast and slow myosin heavy chain to classify the myofibers into three categories: fast‐, slow‐, and mixed (hybrid)‐type myofibers (myofibers expressing both fMHC and sMHC). Our results revealed an increase in the percentage of slow‐type myofibers and a decrease in the percentage of fast‐type myofibers during the repair process. The percentage of hybrid‐type myofibers increased 2 weeks after injury, then gradually decreased over the following 6 weeks. Similarly, our analysis of centronucleated myofibers showed an increase in the percentage of slow‐type myofibers and decreases in the percentages of fast‐ and hybrid‐type myofibers. We also investigated the relationship between myofiber type conversion and peroxisome proliferator‐activated receptor‐γ coactivator‐1α (PGC‐1α). The expression of both PGC‐1α protein, which is expressed in both the nucleus and the cytoplasm of regenerating myofibers, and sMHC protein increased with time after cardiotoxin injection, but we observed no significant differential expression of fMHC protein in regenerating muscle fibers during muscle repair. PGC‐1α‐positive myofibers underwent fast to slow myofiber type conversion during the repair process. These results suggest that PGC‐1α contributes to myofiber type conversion after muscle injury and that this phenomenon could influence the recovery of the injured muscle. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1534–1540, 2007
Reserve mobilisation in mesquite (Prosopis juliflora) seed (Leguminosae)
Authors: Gallão Maria I , Vieira Ícaro GP , Mendes Francisca NP , de Souza Alex SN , de Brito Edy S 
Published: June 2007

AbstractThe seeds of Prosopis juliflora (mesquite) have a water barrier composed of the palisade layer present in the seed tegument and galactomannans in the endosperm. Changes in the morphological and physiological states of seeds are usually accompanied by changes in their metabolism. The aim of this study was to detect and characterise the main reserves and their mobilisation during and following germination of P. juliflora seeds. Sections of seeds 0, 24, 48 and 72 h after the onset of the imbibing process were evaluated by light microscopy, and seed reserves were extracted and quantified. Polysaccharides were isolated and characterised by 1H nuclear magnetic resonance (NMR) spectroscopy. In mesquite seeds a well‐developed endosperm, consisting largely of the storage carbohydrate (galactomannans), lies between the seed coat and the cotyledons. Germination was complete after 24 h of imbibition. At this time, morphological changes were observed in stained protein bodies. Chemical analysis showed a decrease in protein levels until 48 h. After 48 h, globular structures were observed in the cotyledon cells, but after 72 h these grains were smaller and their content was reduced. Polarisation microscopy confirmed that this material was composed of starch grains. The 1H NMR spectrum of P. juliflora seeds showed that sucrose was used following germination. Apparently, sucrose is the transport sugar mobilised from reserve stocks for seedling growth. Parallel to endosperm galactomannan degradation, starch is produced transitorily in the cotyledon. Copyright © 2007 Society of Chemical Industry
Dose dependency between cigarette consumption and reduced maternal serum PAPP‐A levels at 11–13+6 weeks of gestation
Authors: Kagan K. O. , Frisova V. , Nicolaides K. H. , Spencer K. 
Published: June 2007

AbstractObjectiveTo examine whether in smokers there is a significant dose dependency between the number of cigarettes per day and levels of free ß‐hCG and pregnancy‐associated plasma protein A (PAPP‐A) at 11–13+6 weeks of gestation.MethodsThis was a retrospective analysis of the maternal serum free ß‐hCG and PAPP‐A levels in relation to the maternal smoking status in 109 263 chromosomally normal singleton pregnancies that had undergone first‐trimester screening for Down syndrome by a combination of fetal nuchal translucency thickness and maternal serum biochemistry.ResultsThere were 95 287 nonsmokers and 13 976 cigarette smokers. The overall median PAPP‐A MoM among cigarette smokers was 0.827, which was 19.6% lower than the value of 1.029 in nonsmokers (p < 0.0001 for log10 MoM). The respective values for β‐hCG MoM were 1.003 for smokers and 1.035 for nonsmokers (p < 0.0001 for log10 MoM) which corresponds to a reduction of 3.1%. There was a significant inverse relationship between the number of cigarettes per day and the level of PAPP‐A MoM (r = 0.989, p < 0.0001) but not the level of free β‐hCG MoM (r = 0.733; p = 0.098). Using a statistical modeling approach we found that the screen‐positive rate when correcting the PAPP‐A MoM by an all or nil smoking factor was reduced by only 0.1% (3.75 vs 3.85%) when compared to correcting with a factor related to the smoking dose per day.ConclusionIn first‐trimester screening for Down syndrome by maternal serum PAPP‐A and free β‐hCG the impact of correcting for the dose dependant rather than the all or nil effect of smoking is marginal. However, a dose dependent correction improves the accuracy of the individual patient‐specific risk. Copyright © 2007 John Wiley & Sons, Ltd.
Divergence of hypertrophic growth and fetal gene profile: the influence of β‐blockers
Authors: Du X‐J 
Published: June 2007

While the expression patterns of cardiac hypertrophy‐related genes have been well documented and widely used as markers for hypertrophy, recent research has revealed uncoupling of hypertrophy‐related gene profiles and hypertrophic growth. The role of β‐adrenergic signalling in the development of hypertrophy is incompletely understood. The finding of an upregulated expression of hypertrophy‐related genes but a suppressed hypertrophy following β‐blockade reveals previously unrecognized sympatho‐adrenergic mechanisms of hypertrophic growth.British Journal of Pharmacology (2007) 152, 169–171; doi:10.1038/sj.bjp.0707353
From Source Material to News Story in New Zealand Print Media: A Prospective Study of the Stigmatizing Processes in Depicting Mental Illness
Authors: Nairn Raymond , Coverdale John , Claasen Donna 
Published: June 2007

Objective: The aim of this study was to analyse how newspaper articles that depict mental illnesses are generated from source materials. Method: From a prospectively collected national sample of print materials involving mental illness, 50 published items that related to the Privacy Commissioner's opinion about disclosure of a psychiatric patient's health information were identified. A copy of the Privacy Commissioner's original Case Note and three news stories about the Case Note distributed by the New Zealand Press Association constituted the database. These materials were subjected to discourse analysis. We identified themes and their transformation from the Case Note through the news stories and examined the impact of these transformations on the stigmatization of mental illness. Results: Four themes were identified: human rights, vulnerability, risk of dangerousness and threat, and mental illness/psychiatric patient. The only potentially positive theme, human rights, was limited both by being fragmented in the source material, and by being utilized, in the published news stories to undermine the legitimacy of the patient's right to privacy. Use of the other themes was consistent with stereotypes about mental illness. Conclusions: Although there were no inaccuracies in the content of the news stories they were substantially more negative than the source material in their depiction of the identified patient. A potentially positive discourse (human rights) was not by itself sufficient to ensure a positive portrayal of mental illness. An understanding of the transformations is important for efforts to effectively combat the stigmatization of those with mental illness.
A Psychological Approach to Research on Teachers' Classroom Decision‐making
Authors: Calderhead James 
Published: June 2007

AbstractA number of different approaches to research on teachers' classroom decision‐making have developed over recent years. This paper outlines a psychological approach, and points out that several exploratory studies of teachers' thoughts and decision‐making indicate that, in the classroom, teachers rarely make decisions in the sense of making choices amongst alternatives at all. It would appear instead that they respond in a rule‐fashioned manner to particular configurations of cues, many of which concern attributes of their pupils. In addition, decision‐making research suggests that several commonly found classroom interaction patterns serve managerial, as opposed to instructional, functions. Whether this is due to inadequacies of the research methods and research designs employed or to the very nature of teaching is problematic. However, differences found between experienced and probationer teachers in both cognitive and behavioural variables would suggest that decision‐making research may make a useful contribution to teacher training.
Practical Work in 11‐13 Science: the context, type and aims of current practice
Authors: Beatty J.W. , Woolnough B.E. 
Published: June 2007

AbstractIt is common experience that a very large amount of science teaching for 11‐13‐year‐olds in the schools of England and Wales is practically based, but little work seems to have been done to investigate it more fully — to analyse the amount, the type and the aims of practical work which science teachers have. This article describes the findings of some research done in 1978 and 79 to study the amount and type of science being taught to the 11‐13‐year‐olds and the aims that their teachers had for doing practical work in it. The results are discussed, and the changes of science teachers aims to practical work since 1962 are considered.
Middle School Attitude Survey
Authors: Taylor Graham , Sayer Brian 
Published: June 2007

AbstractThe investigation explored some aspects of attitudes held by teachers towards the 9‐13 Middle School. The data were obtained from teachers working in 9‐13 Middle Schools within one northern Metropolitan District. The sample consisted of 708 Middle School teachers, from a total Middle School teaching population of 1063 teachers. The data were collected during the period November 1980 to March 1981. Findings indicated that a majority of these practising teachers held positive attitudes towards the 9‐13 Middle School. Separate ratings were obtained for a variety of subgroups within the total population based on age, sex, status in school and previous training and experience.A questionnaire, in addition to the attitude questionnaire, produced data indicating almost a 2:1 preference for the 9‐13 as opposed to the 8‐12 Middle School. Even accepting the fact that some teachers may prefer the status quo when asked to state a preference in an unstable educational climate such as we have now, it is still felt to be revealing that such a large majority indicated favour for the 9‐13 Middle School. It was also found that over 70% of all the sample teachers found working in a 9‐13 Middle School a satisfying experience.
Sources of Stress for Primary School Head Teachers in New Zealand
Authors: Galloway David , Panckhurst Fay , Boswell Kathleen , Boswell Colin , Green Kathy 
Published: June 2007

AbstractA stratified sample of 40 primary school head teachers in the North Island of New Zealand completed a 63 item check‐list on sources of stress. The most highly rated items referred to stress arising from management of time, administrative tasks and interpersonal relationships. A principal components analysis identified four factors, labelled: staff, work‐load/administration, role conflict, and meetings. Comparison between groups suggested that experiences of stress were related to the school's catchment area, to the adequacy of its buildings and to the head's teacher's responsibilities.
Approaches to Teaching in Colleges of Higher Education
Authors: Gibbs Ian , Harland John 
Published: June 2007

AbstractThe article outlines, and then discusses the implications of, student reaction to different approaches to teaching and instruction in former colleges of education. The research, commissioned by the Combined Colleges Research Group, presents a series of snapshots clustered around subject groupings, courses and teaching techniques.With increasing pressure on staff student ratios, higher education, and the colleges in particular, have been forced to place greater emphasis on lecture based teaching. For the former colleges of education this is especially unfortunate at a time when so many of their BEd and BA graduates wilt teach in schools and would benefit from good models. In addition, there is an urgent need for the colleges to offer their students new approaches to learning as part of the attempt to develop a more distinctive profile.
Talking about Science Based Issues: do boys and girls differ?
Authors: Solomon Joan , Harrison Kate 
Published: June 2007

AbstractA research project which encouraged 17 year‐old students to form friendship groups and record their own discussions of controversial issues presented on video, provided one set of data for examining the talk of girls and boys. Another set of data was obtained from the individual questionnaire responses. In the light of previous models of gender responses to science and technology, and to ethical dilemmas, these data were analysed and compared. Although the questionnaire data yielded many of the expected differences there were far fewer in the actual discussions. The expected tendency of boys to make more decontextualised moral statements was only to be found in the opening sequence of the discussions. The authors argue that social factors bring about an exchange of perspectives which blur gender differences, and render group discussion a valuable co‐educational process.
Personal Reflections on the Use of Photography in an Ethnographic Case Study
Authors: Prosser Jon 
Published: June 2007

AbstractIn the past photography has been little used in educational research. If it is to play a greater role in the future there will be a need to establish a set of practical and theoretical guidelines. This article describes a practical application of photography to a case study of a newly formed comprehensive school. A broad strategy is presented, giving an outline of photographic techniques and their uses within a qualitative research framework. The approach described is not intended to be a definitive model, merely a modus operandi upon which to focus debate.