bluuebunny/crossref_metadata_2025 huggingface dataset:
Terpenoid biomaterials
Authors: Bohlmann Jörg , Keeling Christopher I.
Published: May 2008

Terpenoids (isoprenoids) encompass more than 40 000 structures and form the largest class of all known plant metabolites. Some terpenoids have well‐characterized physiological functions that are common to most plant species. In addition, many of the structurally diverse plant terpenoids may function in taxonomically more discrete, specialized interactions with other organisms. Historically, specialized terpenoids, together with alkaloids and many of the phenolics, have been referred to as secondary metabolites. More recently, these compounds have become widely recognized, conceptually and/or empirically, for their essential ecological functions in plant biology. Owing to their diverse biological activities and their diverse physical and chemical properties, terpenoid plant chemicals have been exploited by humans as traditional biomaterials in the form of complex mixtures or in the form of more or less pure compounds since ancient times. Plant terpenoids are widely used as industrially relevant chemicals, including many pharmaceuticals, flavours, fragrances, pesticides and disinfectants, and as large‐volume feedstocks for chemical industries. Recently, there has been a renaissance of awareness of plant terpenoids as a valuable biological resource for societies that will have to become less reliant on petrochemicals. Harnessing the powers of plant and microbial systems for production of economically valuable plant terpenoids requires interdisciplinary and often expensive research into their chemistry, biosynthesis and genomics, as well as metabolic and biochemical engineering. This paper provides an overview of the formation of hemi‐, mono‐, sesqui‐ and diterpenoids in plants, and highlights some well‐established examples for these classes of terpenoids in the context of biomaterials and biofuels.
Improvement of biomass through lignin modification
Authors: Li Xu , Weng Jing‐Ke , Chapple Clint
Published: May 2008

Lignin, a major component of the cell wall of vascular plants, has long been recognized for its negative impact on forage quality, paper manufacturing, and, more recently, cellulosic biofuel production. Over the last two decades, genetic and biochemical analyses of brown midrib mutants of maize, sorghum and related grasses have advanced our understanding of the relationship between lignification and forage digestibility. This work has also inspired genetic engineering efforts aimed at generating crops with altered lignin, with the expectation that these strategies would enhance forage digestibility and/or pulping efficiency. The knowledge gained from these bioengineering efforts has greatly improved our understanding of the optimal lignin characteristics required for various applications of lignocellulosic materials while also contributing to our understanding of the lignin biosynthetic pathway. The recent upswing of interest in cellulosic biofuel production has become the new focus of lignin engineering. Populus trichocarpa and Brachypodium distachyon are emerging as model systems for energy crops. Lignin research on these systems, as well as on a variety of proposed energy crop species, is expected to shed new light on lignin biosynthesis and its regulation in energy crops, and lead to rational genetic engineering approaches to modify lignin for improved biofuel production.
Deciphering gene regulatory networks that control seed development and maturation in Arabidopsis
Authors: Santos‐Mendoza Monica , Dubreucq Bertrand , Baud Sébastien , Parcy François , Caboche Michel , Lepiniec Loïc
Published: May 2008

Seeds represent the main source of nutrients for animals and humans, and knowledge of their biology provides tools for improving agricultural practices and managing genetic resources. There is also tremendous interest in using seeds as a sustainable alternative to fossil reserves for green chemistry. Seeds accumulate large amounts of storage compounds such as carbohydrates, proteins and oils. It would be useful for agro‐industrial purposes to produce seeds that accumulate these storage compounds more specifically and at higher levels. The main metabolic pathways necessary for oil, starch or protein accumulation are well characterized. However, the overall regulation of partitioning between the various pathways remains unclear. Such knowledge could provide new molecular tools for improving the qualities of crop seeds (Focks and Benning, 1998,Plant Physiol.118, 91). Studies to improve understanding of the genetic controls of seed development and metabolism therefore remain a key area of research.

In the model plant Arabidopsis, genetic analyses have demonstrated thatLEAFY COTYLEDONgenes, namelyLEC1,LEC2andFUSCA3(FUS3), are key transcriptional regulators of seed maturation, together withABSCISIC ACID INSENSITIVE 3(ABI3). Interestingly, LEC2, FUS3 and ABI3 are related proteins that all contain a ‘B3’ DNA‐binding domain. In recent years, genetic and molecular studies have shed new light on the intricate regulatory network involving these regulators and their interactions with other factors such as LEC1, PICKLE, ABI5 or WRI1, as well as with sugar and hormonal signaling. Here, we summarize the most recent advances in our understanding of this complex regulatory network and its role in the control of seed maturation.
Cell‐wall carbohydrates and their modification as a resource for biofuels
Authors: Pauly Markus , Keegstra Kenneth
Published: May 2008

Plant cell walls represent the most abundant renewable resource on this planet. Despite their great abundance, only 2% of this resource is currently used by humans. Hence, research into the feasibility of using plant cell walls in the production of cost‐effective biofuels is desirable. The main bottleneck for using wall materials is the recalcitrance of walls to efficient degradation into fermentable sugars. Manipulation of the wall polysaccharide biosynthetic machinery or addition of wall structure‐altering agents should make it possible to tailor wall composition and architecture to enhance sugar yields upon wall digestion for biofuel fermentation. Study of the biosynthetic machinery and its regulation is still in its infancy and represents a major scientific and technical research challenge. Of course, any change in wall structure to accommodate cost‐efficient biofuel production may have detrimental effects on plant growth and development due to the diverse roles of walls in the life of a plant. However, the diversity and abundance of wall structures present in the plant kingdom gives hope that this challenge can be met.
Plant surface lipid biosynthetic pathways and their utility for metabolic engineering of waxes and hydrocarbon biofuels
Authors: Jetter Reinhard , Kunst Ljerka
Published: May 2008

Due to their unique physical properties, waxes are high‐value materials that are used in a variety of industrial applications. They are generated by chemical synthesis, extracted from fossil sources, or harvested from a small number of plant and animal species. As a result, the diversity of chemical structures in commercial waxes is low and so are their yields. These limitations can be overcome by engineering of wax biosynthetic pathways in the seeds of high‐yielding oil crops to produce designer waxes for specific industrial end uses. In this review, we first summarize the current knowledge regarding the genes and enzymes generating the chemical diversity of cuticular waxes that accumulate at the surfaces of primary plant organs. We then consider the potential of cuticle biosynthetic genes for biotechnological wax production, focusing on selected examples of wax ester chain lengths and isomers. Finally, we discuss the genes/enzymes of cuticular alkane biosynthesis and their potential in future metabolic engineering of plants for the production of renewable hydrocarbon fuels.
Microalgal triacylglycerols as feedstocks for biofuel production: perspectives and advances
Authors: Hu Qiang , Sommerfeld Milton , Jarvis Eric , Ghirardi Maria , Posewitz Matthew , Seibert Michael , Darzins Al
Published: May 2008

Microalgae represent an exceptionally diverse but highly specialized group of micro‐organisms adapted to various ecological habitats. Many microalgae have the ability to produce substantial amounts (e.g. 20–50% dry cell weight) of triacylglycerols (TAG) as a storage lipid under photo‐oxidative stress or other adverse environmental conditions. Fatty acids, the building blocks for TAGs and all other cellular lipids, are synthesized in the chloroplast using a single set of enzymes, of which acetyl CoA carboxylase (ACCase) is key in regulating fatty acid synthesis rates. However, the expression of genes involved in fatty acid synthesis is poorly understood in microalgae. Synthesis and sequestration of TAG into cytosolic lipid bodies appear to be a protective mechanism by which algal cells cope with stress conditions, but little is known about regulation of TAG formation at the molecular and cellular level. While the concept of using microalgae as an alternative and renewable source of lipid‐rich biomass feedstock for biofuels has been explored over the past few decades, a scalable, commercially viable system has yet to emerge. Today, the production of algal oil is primarily confined to high‐value specialty oils with nutritional value, rather than commodity oils for biofuel. This review provides a brief summary of the current knowledge on oleaginous algae and their fatty acid and TAG biosynthesis, algal model systems and genomic approaches to a better understanding of TAG production, and a historical perspective and path forward for microalgae‐based biofuel research and commercialization.
The calmodulin‐binding protein kinase 3 is part of heat‐shock signal transduction in Arabidopsis thaliana
Authors: Liu Hong‐Tao , Gao Fei , Li Guo‐Liang , Han Jin‐Long , Liu De‐Long , Sun Da‐Ye , Zhou Ren‐Gang
Published: May 2008

Based on our previous findings, we proposed a pathway for the participation of Ca2+/calmodulin (CaM) in heat‐shock (HS) signal transduction. The specific mechanism by which CaM regulates activation of heat‐shock transcription factors (HSFs) is not known. CaM‐binding protein kinases (CBK) are the most poorly understood of the CaM target proteins in plants. In this study, using a yeast two‐hybrid assay, we found that AtCBK3 interacts with AtHSFA1a. Fluorescence resonance energy transfer was used to confirm the interaction between AtCBK3–YFP and AtHSFA1a–CFP. Furthermore, we demonstrate that purified recombinant AtCBK3 phosphorylated recombinant AtHSFA1a in vitro. We also describe the results of both downregulation of AtCBK3 expression and ectopic overexpression in Arabidopsis thaliana. The T‐DNA insertion AtCBK3 knockout lines had impaired basal thermotolerance, which could be complemented by transformation of plants with the native gene. Overexpression of AtCBK3 resulted in plants with increased basal thermotolerance. Results from real‐time quantitative PCR and protein gel‐blot analyses suggest that AtCBK3 regulates transcription of heat‐shock protein (HSP) genes and synthesis of HSPs. The binding activity of HSF to the heat‐shock element (HSE), the mRNA level of HSP genes and synthesis of HSPs were upregulated in AtCBK3‐overexpressing lines after HS, but downregulated in AtCBK3 null lines. These results indicate that AtCBK3 controls the binding activity of HSFs to HSEs by phosphorylation of AtHSFA1a, and is an important component of the HS signal transduction pathway.
Genetic and physical interaction suggest that BARREN STALK1 is a target of BARREN INFLORESCENCE2 in maize inflorescence development
Authors: Skirpan Andrea , Wu Xianting , McSteen Paula
Published: May 2008

Organogenesis in plants is controlled by polar auxin transport. In maize (Zea mays), barren inflorescence2 (bif2) encodes a co‐ortholog of the serine/threonine protein kinase PINOID (PID), which regulates auxin transport in Arabidopsis. In this paper, we report that the basic helix‐loop‐helix transcription factor BARREN STALK1 (BA1) is a putative target of BIF2, revealing a previously unknown function of BIF2 in the nucleus. Both bif2 and ba1 are required for axillary meristem initiation during inflorescence and vegetative development in maize. Using a yeast two‐hybrid approach, we identified BA1 as an interacting partner with BIF2. We confirmed the interaction by in vitro pull‐down assays, and demonstrated that BIF2 phosphorylates BA1 in vitro. Previously, RNA in situ hybridization showed that bif2 and ba1 are both expressed during axillary meristem initiation. Here, we heterologously expressed BIF2 and BA1, and found that they co‐localize in the nucleus. Based on these findings, we propose that in addition to regulating auxin transport at the cell periphery, BIF2 also functions in the nucleus by interacting with BA1 to promote axillary meristem initiation. Double mutant analysis is consistent with these results, showing that bif2 and ba1 have overlapping as well as unique roles in inflorescence development.
A new whole‐mount DNA quantification method and the analysis of nuclear DNA content in the stem‐cell niche of Arabidopsis roots
Authors: Willemse Joost , Kulikova Olga , De Jong Hans , Bisseling Ton
Published: May 2008

A semi‐automated method to quantify fluorescence intensity of objects in intact organs and tissues, composed of several cell layers, has been designed. The method has been developed on whole‐mount propidium‐iodide stained Arabidopsis thaliana (Arabidopsis) root tips, in which the DNA content of individual nuclei could be quantified. A diameter of less than 150 μm makes this organ most appropriate for whole‐mount imaging. Further advantages are the lack of chlorophyll and transparent cell walls, with only a little background fluorescence. The method has a great advantage over flow cytometry, as the information regarding the positions of nuclei is maintained, and nuclei with aberrant DNA content can be re‐assessed individually, which facilitates the efficient distinction between technical artefact and aberrant DNA content. Our averaging 3D method calculates the average of the summed fluorescence intensities of all sections of a nucleus and interpolates the missing sections, thereby allowing for the correction of detection problems. Furthermore, this method has the advantage of detecting objects in tissues covering multiple cell layers. The results of our method in Arabidopsis root tips showed that the quiescent centre cells, which rarely divide, are diploid, and are arrested in G1 or G0. Most stem cells, with the exception of those of the vascular tissue, are diploid cells, and their rather low division rate is caused by an elongated G1 phase. In contrast, the majority of the vascular stem cells are tetraploid.
SOC1 translocated to the nucleus by interaction with AGL24 directly regulates LEAFY
Authors: Lee Jungeun , Oh Mijin , Park Hanna , Lee Ilha
Published: May 2008

SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) is one of the flowering pathway integrators and regulates the expression of LEAFY (LFY), which links floral induction and floral development. However, the mechanism by which SOC1, a MADS box protein, regulates LFY has proved elusive. Here, we show that SOC1 directly binds to the distal and proximal region of the LFY promoter where critical cis‐elements are located. Intragenic suppressor mutant analysis shows that a missense mutation in the MADS box of SOC1 causes loss of binding to the LFY promoter as well as suppression of the flowering promotion function. The full‐length SOC1 protein locates in the cytoplasm if expressed alone in protoplast transient expression assay, but relocates to the nucleus if expressed with AGAMOUS‐LIKE 24 (AGL24), another flowering pathway integrator and a MADS box protein. The domain analysis shows that co‐localization of SOC1 and AGL24 is mediated by the MADS box and the intervening region of SOC1. Finally, we show that LFY is expressed only in those tissues where SOC1 and AGL24 expressions overlap. Thus, we propose that heterodimerization of SOC1 and AGL24 is a key mechanism in activating LFY expression.
Seasonal influences on quantitative changes in sweat‐associated anatomy in native and thoroughbred horses
Authors: Sneddon Jennifer C. , Ritruechai Pattama , De Yanés Gesa Staats , Howard C. Vyvyan
Published: May 2008

Stereological techniques were used to assess seasonal influences on morphometric characteristics of hair follicles, sweat and sebaceous glands in abattoir pelts of ponies (PN), thoroughbred (TB) and non‐thoroughbred (NTB) horses. Volume density of sweat glands increased significantly from winter (0.061) to summer (0.098) in TB, and showed no change in NTB and a positive tendency in PN. There might be a body surface area : volume effect for sweat gland parameters as PN had smaller values than either TB or NTB, probably attributable to control of heat loss in winter. In summer, the skin remained thick and the volume density of sebaceous glands was increased in NTB, in contrast to TB where both were decreased. It is possible that in summer, sebum has a particular importance in NTB to enhance wicking of sweat through the pelt. TB showed significantly higher volume measurements of sebaceous glands than NTB and PN for winter: sebum has probably a special importance for water‐proofing in TB in winter. PN showed no significant seasonal changes in sebaceous glands, but had a thinner summer skin. Winter values for hair follicle volume density between equine groups were similar (TB, NTB 0.066; PN 0.059), as was skin thickness (1.14–1.19 mm). The volume density lowered significantly in summer in TB and NTB. The volume of hair follicles under a unit area of skin surface decreased significantly in TB and nonsignificantly in NTB and PN. The seasonal adaptations of the skin shown here were most pronounced in TB and differed between breeds.
Seed production and subsequent seed germination of Senecio vulgaris (groundsel) grown alone or in autumn‐sown crops
Authors: LUTMAN P J W , BERRY K J , FREEMAN S E
Published: May 2008

Senecio vulgaris is a common weed of agriculture in the UK, but is also of food value to invertebrates and birds. Thus, it may be beneficial to retain it within agricultural ecosystems to enhance overall biodiversity. A less intensive approach to weed management requires a sound understanding of weed population dynamics so as to avoid unacceptable population growth. Experiments were carried out in 2003 and 2004 to assess seed production, and subsequent germination, by S. vulgaris growing alone, in winter wheat, or in winter field beans. Plant and seed samples were collected during May and June. There was a strong allometric relationship between capsule number and plant weight, irrespective of the year or the presence of crop competition. Numbers of seeds/capsule varied slightly from 51 to 66 seeds per capsule. Plants growing alone were estimated to produce 8471 to 12 887 seeds per plant, whilst those in wheat only 923 to 2156. Germination tests in Petri dishes in incubators showed that virtually all seeds were viable and germinated under daily alternating light:dark conditions within 10 days. Seeds in continuous dark germinated less readily, reaching only 30% after 21 days. On the basis of this and other published work, it would appear that the retention of S. vulgaris in arable fields will not pose a major threat to the long‐term viability of crop production.
Using genomic biology to study liver metabolism*
Authors: Swanson K. S.
Published: May 2008

The liver plays a central role in coordinating the body’s metabolism, including glucose homeostasis, xenobiotic metabolism and detoxification, and steroid hormone synthesis and degradation. Many of the regulatory effects in response to diet initially occur in the liver, which then modulates the activities of other organs in terms of nutrient utilization and metabolism. The health consequences of abnormal liver function are widespread, many of which are not entirely understood. Recent advances in genomic biology, nanotechnology, computer science and related fields have supplied researchers with a powerful set of tools for the laboratory and clinic. Because nutrient status has been proven to be an important factor in health and disease, the use of these tools to identify nutrient–gene interactions and their association with disease has greatly increased over the past decade. Given its great importance to intermediary metabolism, the liver has been one of the primary organs of focus in recent nutrigenomic experiments. This paper will provide a brief synopsis of the recent technological advancements that may be applied to nutrition research, common mechanisms by which nutrients and genes interact with one another, a few examples pertaining to hepatic function, and future directions in the field.
Liver lipid metabolism
Authors: Nguyen P. , Leray V. , Diez M. , Serisier S. , Bloc’h J. Le , Siliart B. , Dumon H.
Published: May 2008

The liver plays a key role in lipid metabolism. Depending on species it is, more or less, the hub of fatty acid synthesis and lipid circulation through lipoprotein synthesis. Eventually the accumulation of lipid droplets into the hepatocytes results in hepatic steatosis, which may develop as a consequence of multiple dysfunctions such as alterations in β‐oxidation, very low density lipoprotein secretion, and pathways involved in the synthesis of fatty acids. In addition an increased circulating pool of non‐esterified fatty acid may also to be a major determinant in the pathogenesis fatty liver disease. This review also focuses on transcription factors such as sterol‐regulatory‐element‐binding protein‐1c and peroxisome proliferator‐activated receptor alpha, which promote either hepatic fatty acid synthesis or oxidation.
Response of broiler finishers to diets containing graded levels of processed castor oil bean (Ricinus communis L) meal
Authors: Ani A. O. , Okorie A. U.
Published: May 2008

A 4‐week feeding experiment was conducted to determine the effects of graded levels of dehulled and cooked castor oil bean (Ricinus communis L) meal on the performance of broiler finishers. Castor oil bean seeds were dehulled and detoxified by cooking in two stages at 100 °C for 50 min per cooking. Sixty 6‐week‐old broiler birds (Anak strain) were randomly divided into four groups of 15 birds each. The groups were fed four isocaloric (2.90 Mcal of metabolizable energy/kg) and isonitrogenous (21% crude protein) diets containing 0%, 10%, 15% and 20% dehulled and cooked castor oil bean meal (CBM) for 4 weeks. Results showed that there were significant (p < 0.05) differences among treatments in average daily feed intake, final body weight, average daily weight gain (ADWG), feed conversion ratio (FCR) and protein efficiency ratio (PER). Birds fed diets containing 0% and 10% CBM had significantly (p < 0.05) higher feed intake than birds on 15% and 20% CBM diets. The lowest feed intake was recorded at the 20% CBM inclusion level. The highest ADWG was observed in birds fed 0% CBM diet, but this was not significantly (p > 0.05) different from the ADWG of birds on 10% CBM diet. Birds fed diets containing10% and 15% levels of CBM had similar and non‐significant (p > 0.05) ADWG. Birds fed 20% CBM diet had the least (p < 0.05) ADWG. Birds fed 0%, 10% and 15% CBM diets had similar FCR and this was significantly (p < 0.05) lower and better than that of birds on 20% CBM diet. The least (p < 0.05) PER was observed in birds fed 20% CBM diet. Birds fed 20% CBM diet had significantly (p < 0.05) higher packed cell volume (PCV) than birds on 10% and 15% CBM diets. Birds fed 0%, 10% and 15% CBM diets had similar (p > 0.05) PCV values. Birds fed diets containing 0%, 10% and 15% levels of CBM had similar and significantly (p < 0.05) lower heamoglobin than birds fed 20% CBM diets. There were also significant (p < 0.05) differences among treatments in dry matter (DM), nitrogen, ether extract (EE) and nitrogen‐free extract (NFE) retention. Birds fed 0% CBM diet had significantly (p < 0.05) higher retention of DM, nitrogen and NFE than birds on 10%, 15% and 20% CBM diets. Birds fed 10% CBM diet had significantly (p < 0.05) higher DM, nitrogen and NFE retention than birds on 15% and 20% CBM diets. The lowest retention of DM, nitrogen and NFE was recorded at the 20% CBM inclusion level. Birds fed 0% CBM diet had significantly (p < 0.05) higher EE retention than birds on 15% and 20% CBM diets. The lowest EE retention was observed at the 20% CBM inclusion level. The results of the study indicate that up to 10% dehulled and cooked CBM can be included in broiler finisher rations for optimum performance.
Rumen fermentation and degradability in buffalo and cattle using the in vitro gas production technique
Authors: Calabrò S. , Moniello G. , Piccolo V. , Bovera F. , Infascelli F. , Tudisco R. , Cutrignelli M. I.
Published: May 2008

An in vitro trial was conducted to investigate the effect of different inoculum sources (buffalo vs. cattle) on rumen fermentation and degradability. Incubations were carried out using rumen fluid obtained from buffalo or cattle fed the same diet [60% grass hay and 40% concentrate; 18 kg dry matter (DM)/day]. The fermentation kinetics of eight feeds commonly used in ruminant nutrition (alfalfa hay, barley meal, beet pulp, corn meal and silage, ryegrass hay and silage and soya bean meal s.e.) were studied with the in vitro gas production technique and rumen fermentation parameters (substrate disappearance, pH and volatile fatty acids production) were determined after 120 h of incubation. The linear relationship indicates that the microbial metabolic pathways of the two inocula for all the substrates were qualitatively similar, albeit often quantitatively different. In this in vitro study, a significant influence of rumen inoculum (buffalo vs. cow) on fermentation and degradability of the examined substrates was found. The differences in buffalo and cattle rumen fermentation can be explained with a different microbial activity of the two ruminant species, because of different amount of microbial population or microbial population constituted by different species of bacteria and protozoa.
Mycobiota and aflatoxins in raw materials and pet food in Brazil
Authors: Campos S. G. , Cavaglieri L. R. , Fernández Juri M. G. , Dalcero A. M. , Krüger C. , Keller L. A. M. , Magnoli C.E. , Rosa C. A. R.
Published: May 2008

Commercial feedstuffs are a basic element in modern pet husbandry in the world. In dogs, the effect of mycotoxins is severe and can lead to death. Few reports on the influence of dietary mycotoxins were found in the scientific literature. The aims of this work were to isolate and identify the mycoflora and to determine the aflatoxins (AFs) natural occurrence in raw materials and ready dry pet food. Therefore, the aflatoxigenic capacity of Aspergillus flavus species was investigated. Aspergillus was the prevalent genera (65–89%) followed by Penicillium and Fusarium spp. Aspergillus flavus was the most prevalent species, followed by Aspergillus sydowii, Aspergillus fumigatus and Aspergillus versicolor. Aspergillus flavus frequencies ranged from 58% to 86% except in sorghum meal. All samples assayed (except corn grains and ready pet food) showed Fusarium spp. contamination. Corn meal and corn meal and gluten samples had 100%Fusarium verticillioides. Fusarium graminearum was isolated from sorghum meal. Aspergillus flavus strains (75%) isolated from raw materials and 57% from pet food were able to produce AFs. All samples showed AFs contamination percentages over 70%; corn and sorghum meal obtained the highest AFs levels. Ready pet food did not show quantitative levels of the tested toxins. This is the first report of the aflatoxigenic capacity by A. flavus from Brazilian pet food.
NBT‐PABA test to assess efficiency and kinetics of substituted proteolytic enzyme action in pancreatic duct ligated minipigs*
Authors: Mößeler A. , Bergemann J. , Becker C. , Stemme K. , Gregory P. C. , Kamphues J.
Published: May 2008

The NBT‐PABA test is an established method for diagnosis of pancreatic exocrine insufficiency. In the present study the NBT‐PABA test was used to test and compare the efficacy of two multienzyme preparations (product A and B) differing in galenic preparation in minipigs in which pancreatic exocrine insufficiency (PEI) was induced by pancreatic duct ligation. Without enzyme substitution no distinct increase in PABA was found in blood after oral administration of NBT‐PABA. Administration of both enzyme preparations led to a clear dose dependent rise in PABA‐concentrations in blood. Interestingly, the two preparations showed different time curves of serum PABA concentration, indicating differences in the kinetic of proteolytic enzyme action. It is concluded that the NBT‐PABA test can be a very useful test for indirectly evaluating proteolytic enzyme efficacy in vivo, and also gives information about the kinetics of enzyme action, not only the end‐result of enzyme action (like digestibility trials which were used traditionally). A single test is performed in a few hours and there is no need for fistulated animals.
Effects of oral L‐carnitine, L‐lysine administration and exercise on body composition and histological and biochemical parameters in pigeons
Authors: Hullár I. , Fekete S. G. , Mézes M. , Glávits R. , Gáspárdy A. , Fébel H.
Published: May 2008

The purpose of this study was to examine whether l‐carnitine and its precursor l‐lysine could have any beneficial effect in racing pigeons, and if so, whether this effect is influenced by the extent of exercise (short‐distance flight: 135 km vs. long‐distance flight: 580 km). Birds were divided into seven groups of animals. Group 1: negative control, no flight, no treatment, Group 2: positive control, placebo treatment before the short‐distance flight, Group 3: 200 mg/day l‐carnitine treatment before the short‐distance flight, Group 4: 400 mg/day l‐lysine treatment before the short‐distance flight, Group 5: positive control, placebo treatment before the long‐distance flight, Group 6: 200 mg/day l‐carnitine treatment before the long‐distance flight, Group 7: 400 mg/day l‐lysine treatment before the long‐distance flight. l‐carnitine, l‐lysine and distilled water (placebo) were orally administered (tube feeding) for 7 days before flight. Just after returning home, blood samples were collected and analyzed for glucose, fructosamine, cholesterol, triglycerides and thiobarbituric acid reactive substances. Pigeons were euthanized using carbon dioxide as an inhalation agent, and the whole body was subjected to proximate analysis. The status at arrival was referred to as a basis for comparison. Sex did not affect the measured parameters. As a result of the l‐carnitine and l‐lysine administrations, the body fat mobilization was higher during the 580 km flight, whereas no changes were noted during the 135 km flight. The main changes in the measured blood parameters were caused by the extent of exercise. This experiment considered the extent of exercise as a factor potentially modulating l‐carnitine supplementation effects. In conclusion, flight distance affected several parameters but the supplements of l‐carnitine and l‐lysine were not effective in the tested situations.
Staphylococcal scalded skin syndrome in an extremely premature neonate: A case report with a brief review of literature
Authors: Kapoor Vishal , Travadi Javeed , Braye Stephen
Published: May 2008

Abstract:  Staphylococcus aureus can cause a spectrum of exfoliative skin conditions including staphylococcal scalded skin syndrome (SSSS) which can present as a severe and life threatening illness in extremely premature neonates. We describe a case of an extremely premature neonate with SSSS and discuss relevant pathology and issues in clinical management.
Breastfeeding duration and postpartum psychological adjustment: Role of maternal attachment styles
Authors: Akman İpek , Kuscu M. Kemal , Yurdakul Ziya , Özdemir Nihal , Solakoğlu Mine , Orhon Lale , Karabekiroğlu Aytül , Özek Eren
Published: May 2008

Aim:  Depressive and anxiety symptoms are common in new mothers. The aim of this study is to explore the link between postpartum psychological adjustment and feeding preferences of the mothers.

Methods:  Sixty mothers and newborns were enrolled in this prospective, longitudinal study. Maternal depressive symptoms were screened by the Edinburgh Postpartum Depression Scale (EPDS), and maternal anxiety level was assessed by the State‐Trait Anxiety Inventory at 1 month postpartum. The Multidimensional Scale of Perceived Social Support was used for the assessment of maternal social support. The Adult Attachment Scale was used to determine the attachment style of the mother. Infants were examined and evaluated at 1 and 4 months of life.

Results:  All mothers started breastfeeding their infants postpartum; 91% and 68.1% continued exclusive breastfeeding at 1 and 4 months, respectively. The first‐month median EPDS score of mothers who breastfeed at the fourth month was statistically significantly lower than those who were not breastfeeding (6 and 12, respectively) (P = 0001). The first‐month median EPDS score of mothers with secure attachment was lower than the median score of mothers with insecure attachment (5 and 9, respectively) (P < 0001). Exclusive breastfeeding rate was not statistically different among mothers with secure and insecure attachment styles. The median state and trait anxiety scores and social support scores of mothers were not different between groups according to breastfeeding status.

Conclusions:  This study has shown an association between higher EPDS scores and breastfeeding cessation by 4 months after delivery.
Octreotide in children with hypoglycaemia due to sulfonylurea ingestion
Authors: Rath Shoshana , Bar‐Zeev Naor , Anderson Kym , Fahy Rosemary , Roseby Rob
Published: May 2008

Abstract:  Sulfonylureas are commonly prescribed for type 2 diabetes mellitus; however, overdose or accidental ingestion may result in profound and prolonged hypoglycaemia with permanent neurological sequelae and death. We describe two cases of children with hypoglycaemia due to presumed accidental ingestion of sulfonylureas, where traditional methods of raising blood sugar levels were unsatisfactory. Two studies describe Octreotide for adults with hypoglycaemia, but there are no studies examining the use of Octreotide in children for this indication. Given that Octreotide has been shown to be safe in children when used for other indications, we used Octreotide to safely restore euglycaemia.
Enterprise bargaining: a case study in the de‐intensification of nursing work in Australia
Authors: Willis Eileen , Toffoli Luisa , Henderson Julie , Walter Bonnie
Published: May 2008

This paper explores labour negotiations between nurses and government in the public health sector in Australia between 1996 and 2005. During this period, industrial negotiations between nurses and government in the public health sector moved from centralized wage determinations to agreements made at the level of the enterprise through the Workplace Relations Act 1996. Simultaneously, public sector nurses reported increased work intensification, a result of new public management strategies. This led to the Australian Nursing Federation negotiating enterprise agreements that included the introduction of highly specified workload algorithms in an attempt to de‐intensify nurses’ labour. The irony of this strategy is that these calculations and tools operate as both a human resource mechanism for maximizing productivity as well as an industrial relations tool for reducing work intensification.
Perspectives on midwifery power: an exploration of the findings of the Inquiry into peripartum hysterectomy at Our Lady of Lourdes Hospital, Drogheda, Ireland
Authors: Matthews Anne , Scott P Anne
Published: May 2008

The Lourdes Hospital Inquiry: An inquiry into peripartum hysterectomy at Our Lady of Lourdes Hospital, Drogheda, Ireland, of 2006 recounts in detail the circumstances within which 188 peripartum hysterectomies were carried out at the hospital between 1974 and 1998. The findings of the inquiry have serious ramifications for Irish healthcare delivery and have implications for many professional groups, including midwives. The findings prompt clear questions about the relative position or power of midwives within maternity care. These questions are examined in this article, through the analysis and application of various theoretical perspectives on power. Critical views of power focus on the socio‐political nature of oppressive structures within society and seek mechanisms to address these. Stemming from structure versus agency debates, Giddens's structuration theory examines the agency‐structure interaction and stresses the centrality of agents’ roles in the social reproduction of structures. Postmodernism, particularly drawing on the work of Michel Foucault, focuses on a fluid conception of power while also describing the nature of disciplinary power. It offers midwives a way of viewing power as productive and dispersed. Drawing on different aspects of these perspectives on power, helps us to understand midwives’ relative positions and power relations and how to enhance these to prevent future tragic outcomes such as those reported in the inquiry report.
Praxis and the role development of the acute care nurse practitioner
Authors: Kilpatrick Kelley
Published: May 2008

Acute care nurse practitioner roles have been introduced in many countries. The acute care nurse practitioner provides nursing and medical care to meet the complex needs of patients and their families using a holistic, health‐centred approach. There are many pressures to adopt a performance framework and execute activities and tasks. Little time may be left to explore domains of advanced practice nursing and develop other forms of knowledge. The primary objective of praxis is to integrate theory, practice and art, and facilitate the recognition and valuing of different types of knowledge through reflection. With this framework, the acute care nurse practitioner assumes the role of clinician and researcher. Praxis can be used to develop the acute care nurse practitioner role as an advanced practice nursing role. A praxis framework permeates all aspects of the acute care nurse practitioner's practice. Praxis influences how relationships are structured with patients, families and colleagues in the work setting. Decision‐makers at different levels need to recognize the contribution of praxis in the full development of the acute care nurse practitioner role. Different strategies can be used by educators to assist students and practitioners to develop a praxis framework.
Examining the potential of nurse practitioners from a critical social justice perspective
Authors: Browne Annette J. , Tarlier Denise S.
Published: May 2008

Nurse practitioners (NPs) are increasingly called on to provide high‐quality health‐care particularly for people who face significant barriers to accessing services. Although discourses of social justice have become relatively common in nursing and health services literature, critical analyses of how NP roles articulate with social justice issues have received less attention. In this study, we examine the role of NPs from a critical social justice perspective. A critical social justice lens raises morally significant questions, for example, why certain individuals and groups bear a disproportionate burden of illness and suffering; what social conditions contribute to disparities in health and social status; and what social mandate NPs ought to develop in response to these realities. In our analysis, we draw on lessons learned from the initial Canadian experience with the introduction of NPs in the 1970s to consider the renewed and burgeoning interest in NPs in Canada, Australia and elsewhere. As we argue, a critical social justice perspective (in addition to the biomedical foci of NP practice) will be essential to sustaining long‐term, socially responsive NP roles and achieving greater equity in health and health‐care.
Loss of heterozygosity of DNA repair gene, hOGG1, in renal cell carcinoma but not in renal papillary adenoma
Authors: Gokden Neriman , Li Liwen , Zhang Haihong , Schafer Robert F. , Schichman Steven , Scott Margie A. , Smoller Bruce R. , Fan Chun‐Yang
Published: May 2008

The kidney is constantly exposed to free radicals due to its active metabolism and processing of toxic metabolites. Among 20 or so free radical‐induced DNA lesions, 8‐oxoquanine is the most abundant and is potentially mutagenic if not sufficiently removed. The human 8‐oxoquanine DNA glycosylase 1 (hOGG1) gene repairs 8‐oxoguanine and resides at 3p25–26, which has frequent loss of heterozygosity (LOH) in clear cell–renal cell carcinoma (CC‐RCC). Even though some studies found similar genetic alterations between renal papillary adenomas (PA) and papillary RCC (PRCC), no studies have been conducted to compare the alterations of hOGG1 gene in PA, PRCC and CC‐RCC. To further explore the relationship between CC‐RCC, PRCC and PA at the genetic level LOH of hOGG1 gene was investigated in these three groups. It was found that 8/8 PRCC (100%) and 8/9 CC‐RCC (88%) had evidence of hOGG1 LOH, whereas all four PA (0%) were devoid of hOGG1 LOH. It is concluded that deletion of hOGG1 gene occurs commonly in PRCC and CC‐RCC but not in renal cortical PA. Further studies are warranted to further explore the exact roles of hOGG1 gene in the development and progression of RCC.
Emergency use of a size 1 laryngeal mask airway in a ventilated neonate with an undiagnosed type IV laryngotracheo‐oesophageal cleft
Authors: RUSSELL PHILIP , CHAMBERS NEIL , DU PLESSIS JEAN , VIJAYASEKERAN SHYAN
Published: May 2008

The perioperative management of a neonate with a type IV laryngotracheo‐oesophageal cleft and exomphalos major is described. Following an otherwise uncomplicated exomphalos repair, this baby became increasingly and inexplicably difficult to ventilate through an endotracheal tube. The emergency use of a laryngeal mask airway as a rescue maneuver allowed positive pressure ventilation, and subsequent diagnosis of the airway abnormality. The difficulties in management of the two co‐existing conditions are discussed.
Single injection paravertebral block for renal surgery in children
Authors: BERTA EMIL , SPANHEL JIRI , SMAKAL OLDRICH , SMOLKA VRATISLAV , GABRHELIK TOMAS , LÖNNQVIST PER‐ARNE
Published: May 2008

Background:  Continuous paravertebral block (PVB) has been successfully used for postoperative analgesia in children. However, data regarding the efficacy of a single injection technique for major renal surgery are still lacking.

Methods:  Following the ethics committee approval and parent informed consent, 24 children (median 10.3 months; range: 2.9–26.8) undergoing major renal surgery were included in a prospective observational pilot study. Following a standardized general anesthetic the patients were administered a single injection low thoracic PVB (loss‐of‐resistance technique; 0.5 ml·kg−1 of levobupivacaine 2.5 mg·ml−1 with epinephrine 5 μg·ml−1) at the end of surgery. Postoperative pain was assessed by Face, Legs, Activity, Cry, Consolability (FLACC) score at predetermined time points and in case of apparent patients’ discomfort during the first 12 postoperative hours. The duration of postoperative analgesia was defined as the interval between PVB and the first supplemental administration of a rescue opioid analgesic. The incidence of complications and postoperative vomiting (POV) was also recorded.

Results:  A successful PVB was achieved in 23/24 patients (95.8%). The median duration of the block was 600 min (range: 180–720 min) with 10 children not requiring any supplemental analgesia during the 12‐h observation period. Vascular puncture was observed in 2/24 children (8.3%) and POV occurred in 4/24 children (16.7%). All complications were considered minor and did not influence recovery.

Conclusions:  Single injection PVB provided clinically relevant postoperative analgesia in children undergoing major renal surgery.
Quality improvement: implementation of a pain management policy in a university pediatric hospital
Authors: MEGENS JOHANNA H.A.M. , VAN DER WERFF DÉSIREE B.M. , KNAPE JOHANNES T.A.
Published: May 2008

Background:  Until recently, individual doctors and nurses in our pediatric hospital made decisions about the application of pain relief in patients, resulting in a wide variety of practice. The main task of our pain group was to develop hospital‐wide practice standards for acute pain management to improve care. One of the key points of the pain policy was the introduction of pain assessment tools (COMFORT and Visual Analogue Scale).

Methods:  A project team supported by the Institute for Healthcare Improvement (CBO) collaborated during 1 year. The pain policy and in particular, the pain assessment tools, were implemented in the postanesthetic care unit (PACU) and surgical ward. The following targets were set: pain assessment will be performed in 95% of cases and the severity of pain will be ‘no or mild pain’ in 95% of cases.

Results:  During the study period, 37% of all proposed pain assessments could be retrieved. The maximum retrievement score was 68%. In 80% of patients, at least one pain score was retrieved. The scores were divided as follows: 67% no or mild pain, 11% moderate pain, 1% severe pain. In the PACU, over 80% of pain assessments were retrieved; in six study weeks, the aimed score of 95% was reached; 94% of patients reported no or mild pain at departure.

Conclusions:  Implementation of a pain policy in a pediatric hospital is a difficult process. Pain management in the PACU fell just short of the set target performances. In the surgical ward, embedding the importance of pain assessment remains a challenge and a prerequisite for quality of care in pain management.
Niche separation of ammonia‐oxidizing bacteria across a tidal freshwater marsh
Authors: Laanbroek Hendrikus J. , Speksnijder Arjen G. C. L.
Published: May 2008

Like many functional groups or guilds of microorganisms, the group of ammonia‐oxidizing bacteria (AOB) consists of a number of physiologically different species or lineages. These physiological differences suggest niche differentiation among these bacteria depending on the environmental conditions. Species of AOB might be adapted to different zones in the flooding gradient of a tidal marsh. This issue has been studied by sampling sediments from different sites and depths within a tidal freshwater marsh along the river Scheldt near the village of Appels in Belgium. Samples were taken in February, April, July and October 1998. Communities of AOB in the sediment were analysed on the basis of the 16S rRNA gene by application of polymerase chain reaction in combination with denaturing gradient gel electrophoresis (DGGE). In addition, moisture content and concentrations of ammonium and nitrate were determined as well as the potential ammonia‐oxidizing activities. Six different DGGE bands belonging to the β‐subclass of the Proteobacteria were observed across the marsh. The community composition of AOB was determined by the elevation in the flooding gradient as well as by the sampling depth. The presence of plants was less important for the community composition of AOB. DGGE bands affiliated with the Nitrosospira lineage were mostly found in the upper part of the marsh and in the deeper layers of the sediment. Two of the three DGGE bands related to the Nitrosomonas oligotropha lineage were more broadly distributed over the marsh, but were predominantly found in the upper layers of the sediment. Members of the environmental Nitrosomonas lineage 5 were predominantly detected in the deeper layers in the lower parts of the marsh. Potential driving factors for niche differentiation are discussed.